U.S. patent application number 09/819141 was filed with the patent office on 2002-05-02 for pharmaceuticals and apparatus providing diagnosis and selective tissue necrosis.
Invention is credited to Mills, Randell L..
Application Number | 20020051751 09/819141 |
Document ID | / |
Family ID | 27535316 |
Filed Date | 2002-05-02 |
United States Patent
Application |
20020051751 |
Kind Code |
A1 |
Mills, Randell L. |
May 2, 2002 |
Pharmaceuticals and apparatus providing diagnosis and selective
tissue necrosis
Abstract
Pharmaceuticals and Apparatus used in combination for diagnosis
and tissue necrosis applicable to provide effective and selective
therapy using the Mossbauer absorption phenomenon. Selected
pharmaceutical compounds containing a radiation absorber isotope
are administered to a tissue and excited by a radiation source
which provides energy at the corresponding resonant Mossbauer
absorption frequency of isotope containing pharmaceutical, where
excitation effects nuclear transitions to cause highly selective
energy absorption in the selected target tissue. For diagnostic
purposes, de-excitation fluorescence of the isotope is monitored.
For therapeutic purposes, the energy is converted to particle
radiation by the isotope at the target tissue by internal
conversion followed by an Auger electron cascade which results in
radiolysis of DNA resulting in lethal double strand breaks in the
DNA molecules of the target tissue. The tissue selectivity is
achieved by providing a Mossbauer absorption frequency of the
target tissue which differs from that of surrounding tissue. The
difference in frequency is due to the properties of the
pharmaceutical, and/or an imposition of external magnetic fields or
narrow beam ultrasonic power at the site of the target tissue. The
magnitude of radiation absorption at the resonant Mossbauer
frequency for the target tissue is of the order of one million
times the absorption of surrounding nontarget tissue, which has a
different Mossbauer absorption frequency, thereby producing
considerably reduced side effects in comparison to conventional
chemotherapy or radiation therapy.
Inventors: |
Mills, Randell L.;
(Cochranville, PA) |
Correspondence
Address: |
LAHIVE & COCKFIELD
28 STATE STREET
BOSTON
MA
02109
US
|
Family ID: |
27535316 |
Appl. No.: |
09/819141 |
Filed: |
March 27, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09819141 |
Mar 27, 2001 |
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08454012 |
May 30, 1995 |
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6224848 |
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08454012 |
May 30, 1995 |
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07950973 |
Sep 23, 1992 |
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07950973 |
Sep 23, 1992 |
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07055591 |
May 28, 1987 |
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07055591 |
May 28, 1987 |
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06849046 |
Apr 7, 1986 |
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4815448 |
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06849046 |
Apr 7, 1986 |
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06713448 |
Mar 19, 1985 |
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4815447 |
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Current U.S.
Class: |
424/9.361 ;
534/15; 536/23.1 |
Current CPC
Class: |
A61N 2005/1098 20130101;
A61K 2121/00 20130101; A61N 5/10 20130101; A61K 51/12 20130101;
A61K 41/0085 20130101 |
Class at
Publication: |
424/9.361 ;
536/23.1; 534/15 |
International
Class: |
A61B 005/055; C07H
021/04; C07F 005/00 |
Claims
What is claimed is:
1. A compound comprising: a Mossbauer absorber atom; and at least
one of: a chemical species capable of binding to DNA; a massive
particle of the group polymers colloids macroaggregates, and
crystals; and a site-selective molecule for a predetermined site
within the body.
2. The compound of claim 1, wherein said Mossbauer absorber atom
comprises an atom from Table 7.
3. The compound of claim 1, wherein said molecule comprises a
molecule from Table 6.
4. The compound of claim 1 wherein the polymers are selected from
the group consisting of proteins including: .sup.57Fe hemoglobin;
.sup.127I thyroxine; .sup.129I thyroxine; .sup.119SN albumin;
.sup.121Sb albumin; .sup.125Te albumin; .sup.73Ge albumin;
.sup.127I albumin; .sup.129I albumin; .sup.201Hg albumin; and
organic and inorganic polymers of the size range of 5-50
nanometers.
5. The compound of claim 1, wherein the polymers are selected from
the group consisting of: dibuty tin(119); dimethylacrylate;
ruthenium(99); bisbipyridine poly 4-vinyl pyridine;
poly[bisbipyridine osmium(189) bisvinylpyridine]; .sup.57Fe
polyvinyl ferrocene; sulfonated polystyrene; nafion; ethylene
diaminetetra acetate polymers; organo silane-styrenesulfonate
polymers; lanthonide; actinide; and transition metals.
6. The compound of claim 1, wherein colloids are selectedfrom the
group consisting of: a carboxyl; a sulphate; a phosphate; a
hydroxide; a sulfide colloid; and a gold colloid.
7. The compound of claim 1 wherein the macroaggregate is selected
from one of the group consisting of: .sup.57Fe ferric hydroxide;
.sup.57Fe ferric hydroxide including one of: lanthanides actinide
or transition metals.
8. The compound of claim 1 wherein the crystal is selected from one
of the group consisting of: water insoluble microprecipitates of
the size range of 5 to 50 nanometers, including the Mossbauer
absorber atom of: 127I.sup.-; 129I.sup.-; AgI; and silver halide
precipitates.
9. The compound of claim 1 wherein the site selective molecule is
selected from the group consisting of a monoclonal antibody,
hematoporphyrin, porphyrin, hormone, and cationic lipophilic dye,
and tat III protein.
10. The compound of claim 1 wherein said Mossbauer absorber atom is
attached to said massive particles as one of an inclusion and an
occlusion.
11. The compound of claim 1 wherein said compound is one of a weak
acid and a weak base, and includes an additional proton.
12. The compound of claim 1, wherein said molecule bond
substantially eliminates translational energy modes in response to
an influx of gamma rays.
13. The compound of claim 1 wherein said Mossbauer absorber atom
bond substantially eliminates vibrational modes in response to an
influx of gamma rays.
14. The compound of claim 1 wherein said Mossbauer absorber atom
has a magnetic moment characteristic.
15. The compound of claim 14 wherein said Mossbauer absorber atom
magnetic moment is responsive to an externally imposed magnetic
field.
16. The compound of claim 15 wherein the interaction of said
magnetic field causes selective alignment of the magnetic
moment.
17. The compound of claim 16, wherein said alignment of the
magnetic moment provides selective absorption according to the
polarization of the gamma rays.
18. The compound of claim 16 wherein the Mossbauer absorber atom
has degenerate magnetic sublevels, and the interaction provides for
the degeneracy of the energy of magnetic sublevels to be
lifted.
19. The compound of claim 1 wherein said Mossbauer absorber atom
undergoes internal conversion upon absorption of gamma rays,
followed by an Auger cascade.
20. The compound of claim 1 wherein said Mossbauer absorber atom
undergoes fluorescence upon absorption of gamma rays.
21. The compound of claim 1, wherein said Mossbauer absorber atom
has a resonant absorption energy and a resonant frequency in
combinations with one of said atoms and said molecules bound
thereto.
22. The compound of claim 13, providing a change of resonance of
said Mossbauer absorber atom according to one of an isomer shift, a
magnetic hyperfine interaction, and a quadrapole hyperfine
interaction.
23. The compound of claim 1, wherein the Mossbauer absorber atom is
bound to a biological target comprises one of intercalation,
hydrogen bonding, electrostatic bonding, and covalent bonding.
24. The compound of claim 13, wherein said biological target
comprises a biological lattice.
25. The compound of claim 24, wherein said biological lattice
comprises a bone matrix.
26. The compound of claim 25 comprising one of .sup.40K, .sup.153
Gd, .sup.155 Gd, .sup.157 Gd, .sup.161 Dy, .sup.163 Dy and
.sup.149Sm.
27. The compound of claim 26, wherein said massive particle
comprises a massive inert carrier, in a recoil sense, of at least
10.sup.8 daltons.
28. A compound comprising: antimony 121 sulfude colloid; .sup.197
Au collidal gold; carboxyl colloid; sulphate colloid; phosphate
colloid; hydroxide colloid; sulfide colloid; gelatin protected
colloid; dextran protected colloid; micelles; liposomes; Te sulfur
colloid; chromic phosphate colloid; yttrium hydroxide; lantanide;
actinide.
29. A pharmaceutical comprising: an effective dosage of at least
one of the compounds of claims 1 and 28; and an acceptable form of
a pharmaceutical carrier.
30. The pharmaceutical of claim 29, wherein said pharmaceutical
carrier comprises one of tragacarth, talc, agar-agar, lactose,
polyglycols, ethanol, water, dextrose, saline and
dimethylsulfoxide.
31. The pharmaceutical of claim 29 having the form of one of a
tablet, liquid, gel, cream, ointment, spray, and lotion.
32. A system for providing localized Mossbauer absorptions and
selective release of energy in an organic medium, comprising: a
Mossbauer absorber atom selectively disposed within said organic
medium; a source of gamma ray energy selectively applied to said
Mossbauer absorber atom, wherein said source and Mossbauer absorber
atom have energy characteristics which differ in at least one of
energy level, polarization and propagation direction relative to
the nuclear moment of the Mossbauer absorber atom nuclei to which
the gamma ray energy is to selectively applied; and means for
conforming the Mossbauer resonance characteristics of said source
and said Mossbauer absorber atom, wherein Mossbauer absorption of
the gamma rays from said source occurs in the Mossbauer absorber
atom.
33. The system of claim 32 wherein said source comprises one of a
magnetized ferromagnetic source, a quadrapole split source and a
filtered source.
34. The system of claim 32 wherein said means for conforming
comprises: means for providing a gradient magnetic field of a
selected flux gradient contour for selectively conforming the
energy characteristics of the Mossbauer absorber atom to the
incident energy at a selected location within said organic
media.
35. The system of claim 34, wherein said field gradient comprises
field lines varying from substantially colinear with the incident
energy from the source to field lines substantially perpendicular
to said incident energy, wherein Mossbauer absorption in the
Mossbauer absorber atom selectively occurs at a selected field line
within the range of varying field lines which permits Mossbauer
absorptions.
36. The system of claim 35, wherein said means for conforming
sequentially provides field lines of radial, transverse and radial
orientation, respectively, in a plane parallel relative to said
incident gamma rays, within said organic media.
37. The system of claim 36, wherein said means for conforming
includes a pair of Helmholtz coils having an axis aligned with an
axis of the organic media, having a flow of current in one of said
Helmholtz coil in opposition to the other of said Helmholtz
coil.
38. The system of claim 36, wherein said means for conforming
includes: a plurality of Helmholtz coils having a common axis
aligned with an axis of the organic media and each having a flow of
current in a common direction; and a plurality of surface coils
having axis perpendicular to the axis of said Helmholtz coils,
wherein said surface coils include at least two coils having a
current flow in mutual opposition.
39. The system of claim 32, wherein said filtered source includes
means for separating wanted from unwanted electromagnetic
radiation.
40. The system of claim 35, wherein said means for separating
includes a crystaline diffraction grating.
41. The system of claim 32, wherein said source of gamma rays
comprises a tunable energy gamma ray source.
42. The system of claim 41, wherein said source of gamma rays
comprises a synchrotron source providing gamma rays of selected
energy levels.
43. The system of claim 32, wherein said means for conforming
comprises means for providing acoustic energy to one of said
organic media and said source.
44. The system of claim 43, wherein said means for providing
acoustic energy provides ultrasound energy.
45. The system of claim 43, wherein said means for providing
acoustic energy provides said acoustic energy along a path
conincident with said applied gamma rays at a selected target
location in said organic media.
46. A process for providing spatially localized Mossbauer
absorption in an organic medium, comprising the steps of:
selectively disposing a Mossbauer absorber atom within said organic
media; applying gamma rays to said Mossbauer absorber atom from a
source, wherein said applied gamma rays and said Mossbauer absorber
atom have energy characteristics which differ in at least one of
energy level, polarization and propagation direction relative to
the nuclear moment of the Mossbauer absorber atom nuclei to which
the gamma ray energy is selectively applied; conforming the
Mossbauer resonance energy characteristic of said Mossbauer
absorber atom and said applied gamma ray energy to provide
Mossbauer absorption of the applied gamma rays by said selectively
disposed Mossbauer absorber atom.
47. The process of claim 46, wherein said step of applying
comprises applying a gamma ray with a monochromatic line.
48. The process of claim 46, wherein said step of conforming
includes providing a gradient magnetic field of a selected flux
gradient contour for selectively conforming the energy
characteristics of the Mossbauer absorber atom to the applied gamma
rays at a selected location within said organic media.
49. The process of claim 46, wherein the step of conforming
comprises the step of applying acoustic energy to one of said
organic media and said source to cause a Mossbauer resonance energy
of the Mossbauer absorber atom to coincide with the gamma ray
energy at the selected location.
50. The process of claim 49, wherein the step of applying an
acoustic energy comprises applying ultrasound energy.
51. A process for providing spatially localized energy absorption
in an organic medium of a biological system, comprising the steps
of: administering a compound containing a Mossbauer absorber atom
which is selectively uptaken to a selected location within said
organic medium of said biological system; applying gamma ray energy
from a source to the location of selective uptake in said organic
medium wherein said gamma ray energy conforms to the Mossbauer
absorption line of the Mossbauer absorber atom at the selected
locations, providing absorption of the gamma rays therein.
52. The process of claim 51 wherein the Mossbauer absorber atom
comprise bone seeking Mossbauer absorber atoms, including one of
.sup.40K, 153 Gd, 155 Gd, 157 Gd, 161 Dy, 163Dy and 149Sm.
53. The process of claim 51 wherein the step of administering a
Mossbauer absorber atom comprises administering a compound
containing a Mossbauer absorber atom.
54. The process of claim 51, wherein the step of administering
comprises the step of administering a compound containing a
Mossbauer absorber atom having a selected molecule bound
thereto.
55. The process of claim 54, wherein said molecule comprises at
least one of: a monoclonal antibody, a hormone, a derivatizing
functionality, a catonic lipophilic dye, a colloid, and an
aggregate molecule.
56. The process of claim 55, wherein said derivatizing
functionality includes hematoporphryin and bleomycin.
57. The process of claim 54, further including the step of binding
one of the Mossbauer absorber atom and the molecule to a portion of
the organic media at the selected location.
58. The process of claim 51, wherein the Mossbauer resonance of
said Mossbauer absorber atom differs from said applied gamma rays,
the process further including the step of: conforming the Mossbauer
resonance characteristics energy of said Mossbauer absorber atom
and said applied gamma rays to provide Mossbauer absorption of the
applied gamma rays by said administered Mossbauer absorber
atom.
59. The process of claim 58, further including the step of
interacting the Mossbauer absorber atom with the organic media at
the selected locations to provide at least one of an isomer shift,
magnetic hyperfine interaction and quadrapole interaction of the
Mossbauer absorber atom nucleus.
60. The process of claim 58, wherein the step of conforming
comprises the step of applying a magnetic field having a selected
field gradient contour for selectively conforming the energy
characteristics of the Mossbauer absorber atom and the applied
gamma rays, permitting gamma ray energy absorption by said
mossbauer absorber atom.
61. The process of claim 58, wherein the step of conforming
comprises the step of applying acoustic energy to one of said
organic media and said source to cause a Mossbauer resonance energy
of the Mossbauer absorber atom to coincide with the gamma ray
energy at the selected location.
62. The process of claim 61, wherein the step of applying an
acoustic energy comprises applying ultrasound energy.
63. A process of providing energy absorption at a selected target
tissue in a biological system,,comprising the steps of:
administering a Mossbauer absorber atom to said biological system
wherein the uptake of the Mossbauer absorber atom in the target
tissue provides a locally unique resonance energy of said Mossbauer
absorber atom; and applying gamma rays having an energy
corresponding to said locally unique resonance of said Mossbauer
absorber atom, permitting gama ray absorption therein.
64. A method of using the compound of claim 1 for medical diagnosis
or treatment, comprising the steps of: administering an effective
amount of the compound to a biological system; and selectively
applying a selected frequency electromagnetic radiation to the
biological system to provide Mossbauer absorption of said
electromagnetic radiation at selected target areas within said
biological system.
65. The method of claim 64 wherein said electromagnetic radiation
comprises gamma rays.
66. The method of claim 64, wherein said step of administering
comprises at least one of intravenous, intramuscular, subcutaneous,
intra-arterial and intra-articular injection of said compound.
67. The method of claim 64, wherein said step of administering
comprises at least one of topical application and oral
administration.
68. The method of claim 64, wherein said step of selectively
applying comprises employing electromagnetic radiation at a dose
effective to eliminate cell lines causing selective necrosis at
said target areas.
69. The method of claim 64, wherein said biological system
comprises an animal; said target area comprises a cancer; and said
Mossbauer absorption by said compound causes cancer necrosis.
70. The method of claim 69, wherein said animal comprises a human.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of my
applications Ser. No. 713,448, filed Mar. 19, 1985; and Ser. No.
849,046, filed Apr. 7, 1986.
FIELD OF THE INVENTION
[0002] The present invention relates to pharmaceuticals and
apparatus to implement the Mossbauer effect for diagnostic and
therapeutic purposes.
BACKGROUND OF THE INVENTION
[0003] In the treatment of tumors by ionizing radiation, typically
X-rays or gamma rays are used. The ideal in radiation therapy of
malignant disease is achieved when the tumor is completely
eradicated, and the surrounding normal tissue, in the treated
volume, shows little or no evidence of structural or functional
injury. The important factor in successful treatment is the
difference in radiosensitivity of neoplastic and normal cells. All
tissues, normal and neoplastic, are affected by radiation so that
radiosensitivity is a relative term. The basic consideration of
radiation therapy is that cells that are actively proliferating or
that cells which are of a primitive type are more sensitive than
normal tissue so that there is usually a considerable margin
between doses that are damaging to neoplastic and to normal cells.
If this is the case, then a multifraction dose schedule decreases
the size of the tumor over time while permitting time between doses
for normal tissue to recover. A constant fraction of tumor cells
are killed with each treatment, and theoretically the tumor can be
completely eliminated with a sufficient number of treatments.
However, normal tissue has a memory of its accumulated radiation
dose such that a threshold to the total dose acquired over the
patient's history is eventually reached. Exceeding this threshold
results in unacceptable side effects. Thus, the tumor volume must
be reduced sufficiently before the threshold is reached or the
cancer is incurable by this modality of therapy.
SUMMARY OF THE INVENTION
[0004] The present invention is pharmaceuticals, apparatus, and a
process which provides diagnosis, therapy and other biological
effects by use of highly selective absorption of radiation called
the Mossbauer effect. Mossbauer absorption which is exploited for
diagnosis and therapy by the present invention is completely
analogous to optical absorption. For purposes of the present
application, Mossbauer resonance is synonymously defined as an
energy and a frequency which are interchangeable by the
relationship:
[0005] For optical absorption, the ultimate source of radiation
consists of excited atoms or molecules which decay to the ground
state. The radiation, after being suitably monochromatized by a
prism or diffraction grating, is incident upon the sample, and the
intensity of the beam which is transmitted through the sample
(absorber) varies as a function of the frequency as the photons of
energy equivalent to electronic, vibrational, rotational, and
translational transitions are absorbed. In Mossbauer abszoption,
the source comprises excited nuclei in appropriate highly bonding
surroundings. The nuclei, in decaying to their ground state, emit
gamma radiation that is highly monochromatic. In fact, the gamma
ray line can be so narrow that its frequency may be shifted
significantly by incorporating the source or absorber in a mass
driver oscillating at moderate velocities to produce a Doppler
effect. The velocity of the mass driver which provides a Doppler
shift to the gamma ray photons functions analogously to the
dispersion device in optical absorption. By varying the driving
velocity, a resonance system can be driven by the emitted gamma
photons with regard to the nuclear energy transitions of the sample
(absorber).
[0006] As part of the present invention, useful application of the
Mossbauer effect in living tissue is provided by an administered
pharmaceutical containing a Mossbauer isotope as the absorber. The
pharmaceutical is resonantly excited by the gamma photons provided
by this apparatus where the gamma ray energy, polarization and
propagation direction are resonant with the nuclear transitions of
the isotope in the target tissue, from which the surrounding
nontarget tissue differs significantly in resonance conditions to
achieve an enhanced therapeutic or diagnostic function and minimum
effects in the nontarget tissue.
[0007] As a further aspect of the present invention the resonant
(Mossbauer) absorption of gamma rays by nuclei of the administered
isotopes at the target tissue, provides a specific, lethal release
of energy to a susceptible biological target such as the DNA of the
target tissue as part of a therapeutic process. Alternatively, the
present invention provides diagrams by monitoring the release of
nonlethal energy, as described in detail, below. An acronym for
Mossbauer Isotopic Resonant Absorption of Gamma Emission,
hereafter, MIRAGE, is created, and the corresponding therapy and
pharmaceuticals are disclosed as MIRAGE therapy and MIRAGE
pharmaceuticals.
[0008] The MIRAGE pharmaceuticals contain Mossbauer absorber
isotopes and bind to a target tissue to become immobilized,
permitting Mossbauer nuclear resonant absorption of gamma radiation
in the vicinity of the target tissue. The excitation is by a
radiation source, the apparatus of the invention, at the
corresponding resonant Mossbauer absorption frequency of selected
tissue having received the administered pharmaceutical where
excitation effects nuclear transitions to cause selective energy
absorption in the selected target tissue. For diagnostic purposes,
de-excitation fluorescence of the isotope is monitored with gamma
ray scanning equipment. For therapeutic purposes, the energy is
converted into particle radiation by the Mossbauer isotope at the
target tissue by internal conversion followed by an Auger cascade
which results in damage to a susceptible biological target such as
radiolysis of DNA resulting in lethal double strand breaks in the
DNA molecules of the target tissue.
[0009] Tissue selectivity is achieved by causing the Mossbauer
effect to occur to a greater extent in the selected target tissue
than the nontarget tissue. One aspect of the present invention
providing selectivity is by administering pharmaceuticals which are
selectively taken up by the selected tissue. Alternate embodiments
of the present invention selectively control Mossbauer resonant
absorption by control of the conditions for resonance of gamma ray
energy, polarization, and propagation direction, wherein
pharmaceuticals when in the vicinity of selected versus nonselected
tissue, have a differential of one or more such conditions. Such
conditioning are made different by magnetic fields or ultrasonic
power which are applied, effecting an absorption differential for
selected versus nonselected tissue. Mossbauer absorption at the
target tissue is provided by shifting the source frequency to
conform to that of the MIRAGE isotope in the vicinity of the target
tissue. Alternately the absorption characteristics of the MIRAGE
isotope is controlled to match the imparted radiation at the site
of the target tissue.
[0010] Apparatus providing the selectively shifted radiation
comprises a Mossbauer source supported by a mass drive or
ultrasonic transducer drive which can suitably "tune" the emitted
radiation to the proper Mossbauer absorption frequency by imparting
a Doppler frequency shift or by shifting the energy of emission
side bands, respectively. In addition, the apparatus includes means
to polarize the emission and possesses means to produce external
magnetic fields and an ultrasonic beam to effect selective
absorption by changing the gamma ray energy and/or polarization and
propagation direction conditions to achieve resonance in the
absorber pharmaceutical selectively.
[0011] In addition, the present invention includes apparatus to
separately and controllably polarize both the emission radiation
and the absorber pharmaceutical at the target tissue to achieve the
desired controlled absorption. Alternate embodiments of the
apparatus according to the present invention provide selectively
controlled external magnetic fields at the target tissue to effect
selective absorption by changing the gamma ray energy and/or
polarization and propagation direction conditions to achieve
resonance in the MIRAGE absorber pharmaceutical. The Apparatus,
Systems, Compounds, Methods, and specifications of use are
described in detail below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] These and other features of the present invention will be
better understood by reading the following detailed description
taken together with the drawing, wherein:
[0013] FIG. 1 is one embodiment of the system apparatus of the
present invention;
[0014] FIG. 2 is an alternate embodiment of the system apparatus of
the present invention;
[0015] FIG. 3 is an alternate embodiment of a portion of the system
of FIGS. 1 or 2, showing the position of surface coils;
[0016] FIG. 3A is a plot of the field produced by the coils
disposed in FIG. 3;
[0017] FIG. 4 is an alternate embodiment of the disposition of
Helmholtz and a surface coil;
[0018] FIG. 4A is a plot of the field produced by the coils of FIG.
4;
[0019] FIGS. 5 and 5A are drawings of a surface coil;
[0020] FIG. 5B is a plot of the field produced by the coil of FIG.
5; and
[0021] FIG. 6 is an isometric view of an alternate embodiment of an
array of coils for use in the system apparatus of FIGS. 1 and
2.
[0022] FIG. 7 is an isometric drawing of a system according to the
present invention showing ultrasound modulation of the gamma ray
source and the Mossbauer atom at the target area; and
[0023] FIGS. 8 and 9 are graphical plots of data related to
radiation therapy.
[0024] FIG. 10 is a drawing of the MIRAGE pharmaceutical
12/29/w.
[0025] FIG. 11 is the decay scheme of .sup.57Co.
[0026] FIG. 12 is an equation to calculate radiation dose.
[0027] FIG. 13 is the decay scheme of .sup.119Sn.
[0028] FIG. 14 is the decay scheme of .sup.121mSm.
[0029] FIG. 15 is a decay scheme of .sup.125I.
[0030] FIG. 16 is the energy level scheme and resultant spectrum
for magnetic hyperfine splitting of an Ig=1/2.fwdarw.Ie={fraction
(3/2)} transition.
[0031] FIG. 17 is the effect of orientation upon the relative line
intensities of a magnetic hyperfine splitting and a quadrapole
splitting of a {fraction (3/2)}.fwdarw.1/2 transition in an
oriented absorber with a unique principle axis system.
[0032] FIGS. 18a and b are the spectra from a single crystal of
.alpha.--Fe.sub.2O.sub.3 cut parallel to the basal plane with the
gamma ray direction along 111.
[0033] FIG. 18a is the spectra of FIG. 18 at 80.degree. K.
[0034] FIG. 18b is the spectra of FIG. 18 at 300.degree. K.
DETAILED DESCRIPTION OF THE INVENTION
[0035] The present invention includes the process of producing
pharmaceuticals having desired Mossbauer nuclear parameters such
that they possess physical and chemical properties which permit the
Mossbauer phenomenon to be selectively effected in the target
tissue. The application includes administering the pharmaceuticals
and producing gamma radiation of the proper polarization,
propagation direction, and energy with the radiation source to
cause selective resonant absorption in the target tissue. The
present invention also includes producing magnetic fields or an
ultrasonic beam both of selected strength and direction with the
apparatus of the radiation source to effect selective gamma ray
absorption in the target tissue via the Mossbauer effect.
[0036] The pharmaceuticals of the present invention and the process
of producing the pharmaceuticals is discussed first, which is
followed by the apparatus used in combination with selected
pharmaceuticals to effect the Mossbauer absorption in a biological
target as a process of the invention to provide a therapeutic or
diagnostic function. The latter, apparatus, provides a
monochromatic source of gamma rays having an emission frequency or
energy at or near the (or substantially monochromatic over the
range of frequencies where Mossbauer absorption may occur in
irradiated tissue) nuclear transitions of one or more Mossbauer
atoms incorporated in the pharmaceuticals. Subsequently discussed
are the features of the present invention wherein the energy which
excites the nuclear transition is released as light which can be
recorded for diagnostic purposes, or the energy is converted into
charged particles or reactive species which irreversible damage a
biological target to effect a therapeutic function.
[0037] Selectivity in treatment or diagnosis is obtained by causing
the gamma ray absorption to occur with the Mossbauer absorber atoms
of the pharmaceuticals in the target tissue to a greater extent
than in the nontarget tissue due to differential uptake of the
pharmaceutical or a differential in the conditions of the source
gamma rays needed to achieve resonant absorption by the absorbers
including a difference in energy and/or a difference in
polarization and gamma ray propagation direction relative to the
direction of the magnetic or quadrapole moments of the absorber
Mossbauer atoms in the pharmaceuticals. Differential uptake
involves physical, chemical, and biological properties of the
pharmaceuticals which influence its uptake by cells.
[0038] The differential resonance conditions of gamma ray energy
and/or polarization and propagation direction are provided by
different chemical and/or physical interactions of the Mossbauer
atoms of the pharmaceuticals with the environment in which they are
present in target versus nontarget tissue. Furthermore, magnetic
fields or an ultrasonic beam are selectively applied to the target
area in such a fashion to produce a differential of these resonance
conditions at different locations. Therefore, treatment is carried
out by irradiating the selected tissue with gamma radiation of the
proper energy and polarization and gamma ray propagation direction
to match the conditions for resonant absorption by the Mossbauer
absorber isotope atoms of the pharmaceutical molecules present in
the target selected tissue.
[0039] Implementation of the process for making MIRAGE
pharmaceuticals involves selecting an atom responsive to the
Mossbauer effect at a convenient frequency, selecting the structure
of the molecule to which the Mossbauer responsive atom (Mossbauer
Atom) is attached, selecting the type of bond to form between the
Mossbauer atom and the remainder of the pharmaceutical and the
position at which the Mossbauer atom is attached. Mossbauer nuclear
parameters (i.e., Table 8, includes absorption line width, recoil
energy, nuclear magnetic moment, internal conversion coefficient,
X-ray energy, magnetic quantum numbers of the ground and excited
state) are used in calculations as demonstrated in the Theoretical
Section, below, to perform the following steps in the design of the
pharmaceutical:
[0040] 1. A Mossbauer atom is selected such that it possesses
chemical reactivity to form a bond of the nature described below
under 3, a large cross-section for absorption of resonant gamma
radiation with de-excitation primarily by particle production or
fluorescence for the purposes of therapy and diagnostic imaging,
respectively, a low recoil energy which is smaller than the
vibrational energy of the bond between the Mossbauer atom and the
remainder of the pharmaceutical molecule, a large nuclear moment
which interacts with an imposed magnetic field to lift the
degeneracy of existing magnetic sublevels to a significant extent
that spatial discrimination with regard to the occurrence of the
Mossbauer effect can be realized by changing the magnetic field
direction and magnitude to change the resonance conditions of gamma
ray energy and/or polarization and propagation direction, and a
small absorption. line width so that aforementioned discrimination
can be realized over small spatial dimensions, and so that an
ultrasonic means of discrimination of shifting the Mossbauer
absorption energy as described in the Theoretical Section can be
realized with low MHz frequencies.
[0041] 2. A molecular structure to which the Mossbauer atom is to
be bound is selected such that it possesses the ability to also be
bound to the selected biological target to immobilize the Mossbauer
atom to prevent degradation of the Mossbauer effect by excitation
of translational modes of the pharmaceutical molecule, that in
certain cases is selectively taken up by the selected tissue, and
that in certain cases interacts with the environment of the
selected tissue differentially relative to nonselected tissue to
cause different conditions to achieve resonance between these
tissues.
[0042] 3. The bond between the Mossbauer atom and the remainder of
the pharmaceutical molecule is selected such that it possesses
vibrational modes which are not excited by the recoil energy of the
absorbed gamma ray; thus, the Mossbauer effect is not degraded by
this mechanism.
[0043] 4. The bonding position of the Mossbauer atom or
functionality to the remainder of the pharmaceutical molecule has
no effect on the binding affinity of the latter for the biological
target.
[0044] The photon flux necessary for effective treatment is
calculated where variables for each of the afore mentioned design
parameters are included in the calculation, and the strength and
direction of imposed magnetic fields to obtain selectivity are also
calculated. Both types of calculations are demonstrated in the
Theoretical Section.
[0045] The pharmaceutical possesses physical and/or chemical
properties which permits it to bind sufficiently tightly to a
massive biological target so that the effective mass of the
Mossbauer atom which is incorporated in the pharmaceutical is the
mass of the biological target. The effective mass is sufficient to
prevent excitation of translational modes of the Mossbauer atom by
the recoil energy of the absorbed gamma ray. Furthermore, the
chemical bond between the Mossbauer atom and the remainder of the
pharmaceutical has a bond energy that precludes excitation of
vibrational modes of the bond by the recoil energy of the absorbed
gamma ray. The pharmaceutical contains at least one Mossbauer atom
which has a large cross-section for absorption and the atom
de-excites primarily by fluorescence in the case of imaging
pharmaceuticals and the atom converts the excitation energy
primarily into charged particles and reactive species in the case
of therapeutic pharmaceuticals. Also, the pharmaceutical possess
physical and chemical properties so that it is selectively taken up
by selected cells, or it possesses Mossbauer nuclear parameters
which permit the nucleus of the Mossbauer atom to interact with an
imposed magnetic field with a resultant change in the resonance
conditions of gamma ray energy and/or polarization and propagation
direction to a sufficient degree that selectivity of target versus
nontarget tissues can be achieved by this interaction.
[0046] A further feature of the present invention is the use of
selected pharmaceuticals and apparatus described herein in
combination to apply the Mossbauer effect to treat selected
tissues. Treatment includes providing selective uptake of a
specific pharmaceutical by the target tissue, and irradiation of
the target tissue with selected energy (frequency) radiation
produced by the apparatus of one embodiment. The apparatus may also
apply a magnetic field to cause the resonance conditions of gamma
ray energy and polarization and propagation direction necessary to
produce nuclear transitions in the absorber, to match these
conditions of gamma rays produced by the source for the case of a
stationary source (non-Doppler shifted, nonultrasonically driven).
And, where the applied pharmaceutical is present in nonselected
tissue, selectivity in treatment is provided by the imposition of
fields by the apparatus to force differential resonance conditions
of gamma ray energy and/or polarization and gamma ray propagation
direction for resonant nuclear absorption by the Mossbauer absorber
atoms of the target tissue to provide treatment to a tissue
selected area or volume.
[0047] Magnetic fields are applied to the body where the field
magnitude and direction change rapidly as a function of position in
the space permeated by the field. The gamma rays of the source are
made to match the gamma ray energy, polarization and propagation
direction conditions for resonant nuclear absorption by the
Mossbauer atoms of the pharmaceuticals present in the target
tissue. Selectivity of treatment in this case is achieved because
the conditions for nuclear resonant absorption in nonselected
tissue throughkwhich the gamma rays travel to the selected tissue
are different from those of the selected tissue.
[0048] The radiation of energy in resonance with the selected
isotope and of proper polarization and propagation direction is
produced by the apparatus which includes a selectable energy source
such as a synchrotron source or a Mossbauer source which
corresponds to the selected isotope (corresponding sources to
selected absorber isotopes to be incorporated into pharmaceuticals
appear in Table 7). The Mossbauer source is incorporated into a
mass drive which can suitably tune the emitted radiation to the
proper Mossbauer absorption frequency by imparting a Doppler shift,
or the Mossbauer source can be adhered to a ultrasonic drive which
creates emission side bands of energy which is selectable according
to the ultrasonic driving frequency as described in the Theoretical
Section, or magnetic fields may be applied to the target tissue
such that the energy conditions for resonant absorption by the
selected absorber isotope of the pharmaceutical are forced to match
those of the stationary source. In addition, the apparatus includes
a polarizing element, to polarize the emission. Polarized gamma
rays are obtained by three methods: magnetized ferromagnetic
sources, quadrapole split sources, or filter techniques. In
addition, the apparatus possesses means to produce external
magnetic fields and ultrasonic beams to change the gamma ray energy
and/or polarization and propagation direction conditions to achieve
resonant absorption in the absorber atoms of the pharmaceuticals to
impart tissue selectivity according to the present invention.
Magnetic fields and ultrasonic beams are produced by powerful
surface coils such as those used in magnetic resonance imaging and
piezo-electric transducers and transducer arrays such as those used
in ultrasonic imaging, respectively. Such magnetic field producing
means and ultrasonic beam producing means are described below in
the Apparatus Section.
[0049] The process of providing selectivity by imparting magnetic
fields with the apparatus involves providing a magnetic field in
space which contains the selected tissue. Thus, spatial
discrimination with regard to the occurrence of the Mossbauer
effect can be realized by selectively changing the field direction
and strength to change the resonance conditions of gamma ray energy
and/or polarization and propagation direction in a specified area
or volume of tissue. The Mossbauer atoms of the pharmaceuticals
possess magnetic moments which interact with the imposed magnetic
fields to cause the effects of creation of nondegenerate magnetic
sublevels and alignment of the nuclear moments along the direction
of the field lines with a concomitant alignment of the tissue
resonance. The lifting of the magnetic sublevel degeneracy changes
the energy for resonant absorption by the Mossbauer atoms and is a
function of the imposed magnetic field strength and the magnetic
moment of the particular absorber atoms. Magnetic fields which
change rapidly in strength and time (for pulsed fields) are used to
create a selective situation where the energy for resonance changes
rapidly along the field gradient; thus, the energy of the source
can be conformed to the energy for resonant absorption by the
absorbers at the selected tissue site such that the resonant
condition is satisfied only over the volume of the selected site.
The alignment effect results in a dependency on the angle between
the alignment direction of the nuclear moments of the absorber
atoms and the propagation direction and polarization properties of
gamma rays for resonant absorption by the absorbers to occur.
Fields which change rapidly in vector direction in space and time
(for pulsed fields) are used to create a rapidly changing spatial
distribution of populations of atoms with the magnetic moments
aligned in different directions. Thus, a magnetic field is provided
wherein the magnetic moments of all of the Mossbauer atoms in the
nonselected tissue through which the gamma ray travels are in a
nonresonant orientation, and the Mossbauer atoms in the selected
tissue are in a resonant orientation. Thus, selectivity is achieved
by this alignment effect according to the transparency of the
nonselected tissue to the gamma rays and absorption by the selected
tissue.
[0050] The process of treatment involves using the pharmaceuticals
and apparatus in combination to cause the Mossbauer effect to occur
to a greater extent in the selected tissue than in the nonselected
tissue. The tissue is irradiated with gamma radiation of energy and
polarization and propagation direction resonant with the nuclear
transitions of the selected tissue. Selectivity is achieved because
the drug is uptaken by the selected tissue to a greater extent than
the interposed nonselected tissue through which the gamma ray
propagates. Or, a magnetic field of rapidly divergent strength and
direction is applied, or an ultrasonic beam is applied. For the
ultrasonic case, the process of effecting selectivity by causing an
ultrasonic beam to intersect the administered gamma ray beam at the
selected tissue site involves producing a component of ultrasonic
motion of the Mossbauer absorber nuclei in the selected tissue in
the direction of the gamma ray beam to produce absorption side
bands of energy different from those of nonselected tissue through
which the gamma rays resonant with a selected side band propagate.
The production of absorption side bands by driving at ultrasonic
frequencies is described in the Theoretical Section. In the
magnetic case, the phenomenon of the magnetic field strength
dependence of the lifting of the degeneracy of magnetic sublevels
of nuclear transitions and nuclear magnetic moment alignment with
the magnetic field lines and the concomitant dependency for
resonant absorption on the angle between the nuclear magnetic
moment and the gamma ray propagation direction and polarization of
the gamma ray can be used to force a matching set of conditions by
the apparatus between the source and the Mossbauer absorber atoms
in the pharmaceuticals in the selected tissue. The parameters which
are changed to achieve this result are the energy of the source
gamma rays (e.g. by changing the velocity of the mass drive), the
polarization of the source gamma rays (e.g. by changing the
direction of the source polarization magnetic field in the case of
a ferromagnetic source), the magnetic field strength gradient (e.g.
by changing the current in the surface coils which give rise to the
field and the distribution of the coils about the treatment
volume), and the propagation direction of the gamma ray by changing
the relative position of the source of magnetic fields and the
source of gamma rays.
[0051] If the set of parameters which produce resonance selectively
in the selected tissue are known (for example from calculations
such as those demonstrated in the Theoretical Section or from prior
experiments), then the therapy is carried out in an open loop
fashion. For example, for the case where the drug is selectively
uptaken by the selected tissue or has a unique energy for
absorption in the selected tissue, the resonance energy of the
source and absorber are forced to match each other by changing the
energy of the source to match the energy of the nuclear transitions
of the absorbers of the pharmaceutical, or the energy of the
transitions of the absorber are changed to match that of the
source. In the former case, the velocity of the mass drive or the
frequency of the ultrasonic transducer can be adjusted, and in the
latter case, magnetic fields can be used to change the energy of
the absorber nuclear transitions. Selectivity can be achieved where
the drug is distributed in nonselected tissue by use of a magnetic
field of strong field gradient so that the energy of resonance is
only met in a small spatial region. Such a magnetic field could be
applied, and the energy of the source adjusted to match that
required for resonance in the selected tissue. This mode of
achieving selectivity could also be used in conjunction with a
polarization mode where the Mossbauer nuclei of the pharmaceuticals
of the selected tissue are aligned with an imposed magnetic field
in a resonant direction with respect to the gamma ray propagation
direction and polarization, and the interposed tissue is made
transparent by orienting the nuclei in a nonresonent direction. An
additional mode of achieving selectivity is to impose a narrow
ultrasonic beam which intersects the administered gamma ray beam to
induce a component of ultrasonic motion of the Mossbauer absorber
nuclei at the selected tissue site to create absorption side bands
of unique energy equal to the energy of the administered gamma rays
as described in the Apparatus and Theoretical Sections.
[0052] If the parameters to achieve resonance between the apparatus
and absorbers are unknown, then the afore mentioned modes of
treatment are carried out in a closed loop fashion using gamma ray
fluorescence. All Mossbauer nuclei undergo fluorescent emission to
a certain extent after resonantly absorbing gamma rays. This
phenomenon is used to detect where resonance is achieved.
Fluorescence occurs at a continuum of angles, and a bank of
detectors surrounding the treatment volume is used to detect the
source of fluorescence, as described below. Thus, the position of
the source of fluorescence is used in a feedback loop which feeds
into a control system which changes the magnetic field strength and
direction; ultrasonic beam frequency, direction and power; and
gamma ray energy, polarization, and propagation direction until the
source of fluorescence is the selected tissue. Treatment is then
carried out to the level of an absorbed dose which is known from
calculation or past experience. A representative calculation of an
effective photon flux for treatment to achieve necrosis and the
associated dose appears in the Theoretical Section as does the
theory of achieving selectivity by the modes mentioned. (Implicit
is that the process for diagnosis is the same as that for treatment
with regards to excitation. Detection is with gamma ray scanning
equipment which can be obtained by modification of existing
radionuclide scanning equipment by one skilled in the art.)
EXPERIMENTAL
A. Synthesis of 12/29/w
[0053] The MIRAGE drug, 12/29/w, was synthesized by forming a
coordinate bond of .sup.57Fe with Bleomycin (see FIG. 10 for the
structure).
[0054] 12/12/w was prepared as follows:
[0055] Iron 57 metal was obtained from New England Nuclear DuPont
and dissolved in concentrated HC1. The acidic solution of iron was
neutralized with sodium hydroxide. 12/29/w was prepared by mixing a
1:2 molar ratio of a neutral aqueous solution of Blenoxane and the
neutralized solution of .sup.57Fe. A stable yellow solution was
obtained as the product.
B. Cell Culture Testing Of MIRAGE Treatment Using MIRAGE Drug
12/29/w
[0056] The human colon and breast cancer cell lines, HT29 and MCF7,
respectively, were obtained from Cambridge Research Lab Inc., and
were negative for mycoplasma or bacterial contamination where these
tests were performed by Kundsin Lab Inc. A bacterial and
mycoplasma-free McCoy cell line was obtained from Kundsin Lab Inc.,
which the Kundsin Lab tested for these organisms. The human breast
and lung cancer cell lines, HTB26 and A549, respectively, were
obtained from the American Type Culture Collection. The cells were
grown in growth media, Dubecco's modified Eagles medium with 10%
fetal bovine serum, 50 ug/ml streptomycin; 10 ug/ml vancomycin, and
2 nM glutamine. The cells were grown in T25 flasks until a
monolayer was obtained. The monolayer of each flask was washed
twice with iron-free growth media and the cells were incubated with
iron-free media to which the drug 12/29/w was added. The control
experiments were no drug and drug for the same exposure time and
concentration. For the MIRAGE treatment experiment, the cell
monolayer was incubated in iron free growth media containing
12/29/w and was irradiated with the 14.4 Kev gamma ray emitted from
a New England Nuclear DuPont .sup.57Co Mossbauer source with a
rhodium matrix where the source was driven at a velocity of +1.5
mm/sec by an Austin Science K4 linear motor controlled by an Austin
Science S-700 drive module where the constant velocity mode was 85%
of the duty cycle. After the time of the experiment had lapsed, the
drug was removed by washing the monolayer twice with iron free
growth media and once with phosphate buffered saline. The cells
were trypsinized with 5% trypsin EDTA and a counted number of cells
from each experiment was passed into a new T25 flask containing
growth media where counting was performed using methylene blue
stain and a hemocytometer.
[0057] The cells were grown as a monolayer for a period of time
after which they were trypsinized and counted a second time using
methylene blue stain and a hemocytometer. The percentage increase
in cell number between counts was normalized to that of the
control.
RESULTS
[0058] The effects of lm rad levels of Mossbauer radiation absorbed
during MIRAGE treatment of the cancer cell lines MCF7, McCoy, HT29,
HTB26, and A549 using the MIRAGE drug 12/19/w appear in Tables 1-5,
respectively.
1TABLE 1 The Effect of MIRAGE Treatment with Drug 12/29/w, on the
MCF7 Cell Line For all experiments the concentration of drug before
addition was 2.3 .times. 10.sup.-4M Bleomycin and 1.02 mM.sup.57
Fe. For all experiments the radiation dose rate was 9 mrads/hr
total and 1 mrad/hr for the 14.4 KeV gamma ray. Proliferation
Relative to Control Volume Volume MIRAGE of Drug of Fe Free
Duration of Poliferation MIRAGE (velocity = Experiment Dispensed
Media in Flask Experiment Time Drug (velocity = +1.5 mm/ Number
(ul) (ml) (hrs) (hrs) Control Alone omm/sec) sec) 2 25 2 1 96 100
36 -- 6.25 3 50 3 1 72 100 45 -- 0 4 50 3 .5 72 100 39 13 2.75 20
50 3 1 120 100 50 -- 5.6
[0059]
2TABLE 2 The Effect of MIRAGE Treatment with Drug 12/29/w, on the
McCoy Cell Line For all experiments the concentration of drug
before addition was 2.3 .times. 10.sup.-4M Bleomycin and 1.022
mM.sup.57Fe For all experiments the radiation dose rate was 9
mrad/hr total and 1 mrad/hr for the 14.4 KeV gamma ray. All
experiments had a duration of one hour; all flasks contained 3 ml
of Fe free media, and 50 .mu.l of drug where indicated.
Proliferation Relative to Control Proliferation MIRAGE Experiment
Time Drug (velocity = Number (hrs) Control Alone +1.5 mm/sec) 6 96
100 88 23.5 8 144 100 80 28.8 9 120 100 80 40 14 120 100 82 39 7
168 100 25 12 11 48 100 34 5 12 120 100 37 26 13 120 100 34 4
[0060]
3TABLE 3 Effect of MIRAGE Treatment with Drug, 12/29/w, on the HT29
Cell Line For all experiments the concentration of drug before
addition was 2.3 .times. 10.sup.4M Bleomycin and 1.02 m M.sup.57Fe.
For all experiments the radiation dose rate was 9 mrad/hr total and
1 mrad/hr for the 14.4 KeV gamma ray. All flasks contained 3 ml of
Fe free media and 50 .mu.l of drug where indicated. Proliferation
Relative to Control Experi- Duration of Proliferation MIRAGE ment
Experiment Time Drug (velocity + Number (hrs) (hrs) Control Alone
+1.5 mm/sec) 15 1 72 100 41 28 16 1 72 100 47 28 18 3 144 100 56
24.6 21 1 96 100 51 29 22 1 96 100 53 37.7 23 3 72 100 55 25 24 3
72 100 63.6 13.6
[0061]
4TABLE 4 The effect of MIRAGE Treatment with Drug 12/29/w, on the
HTB 26 Cell Line. For all experiments, the concentration of drug
before addition was 2.3 .times. 10.sup.-4M Bleomycin and 1.02
mM.sup.57Fe. For all experiments the radiation dose rate was 8.3
mrad/hr total and .93 mrad/hr for the 14.4 KeV gamma ray. All
experiments had a duration of one hour, 5 min. except experiment 27
which had a duration of five hours; all flasks contained 3 ml of Fe
free media, and 50 .mu.l of drug where indicated. Proliferation
Relative to Control Proliferation MIRAGE Experiment Time Drug
(velocity = Number (hrs) Control Alone +1.5 mm/sec) 25 192 100 78.9
31.5 26 192 100 71.4 23.8 27 168 100 82 0 28 168 100 67 17 30 144
100 88 25 31 120 100 92 33 32 120 100 100 20 x = 82.76 x = 21.47
.sigma..sub.n = 10.7 .sigma..sub.n = 10.2
[0062]
5TABLE 5 The Effect of MIRAGE Treatment with Drug 12/29/w, on the
A549 Cell Line For all experiments the concentration of drug before
addition was 2.3 .times. 10.sup.-4M Bleomycin and 1.02 mM.sup.57Fe.
For all experiments the radiation dose rate was 8.3 mrad/hr total
and .93 mrad/hr for the 14.4 KeV gamma ray. All experiments had a
duration of one hour, 5 mins; all flasks contained 3 ml of Fe free
media, and 50 .mu.l of drug where indicated. Proliferation Relative
to Control Proliferation MIRAGE Experiment Time Drug (velocity =
Number (hrs) Control Alone +1.5 mm/sec) 33 192 100 87.5 12.5 34 192
100 80 20 35 168 100 77 7.7 36 168 100 100 20 37 144 100 69.4 19.4
38 144 100 83.3 20.8 39 120 100 97 8.8 40 120 100 70.1 17.5 x =
83.04 x = 15.8 .sigma..sub.n = 10.6 .sigma..sub.n = 5.0
DISCUSSION
[0063] A statistically significant effect was observed with mrad
levels of radiation. Previous studies indicate that at least 500
rads of conventional X-rays or gamma rays is necessary to register
a similar effect. 500 rads is 5.times.10.sup.5 times the level of
radiation used in these MIRAGE treatment experiments. Furthermore,
lmrad of radiation is far below levels which are toxic and can be
compared to 200 mrad which is the yearly background dose.
Furthermore, the MIRAGE pharmaceutical need not be toxic via
chemical or biological reactivity, and pharmaceutical and radiation
nontoxicity has implications of nontoxic human therapy for the
elimination of a pathological cell population. Previous experiments
demonstrated that the most potent killing effect in cells by
radiation is from secondary particles produced by internal
conversion of gamma ray energy followed by an Auger cascade which
results in the radiolysis of the cell's genetic material. The
present experiments indicate that it is possible to effect this
eradication mechanism with nontoxic levels of radiation which are
six orders of magnitude less than that of conventional radiation
therapy where the Mossbauer effect was exploited for treatment. The
ability to control the occurrence of the Mossbauer effect by the
manipulation of the resonance conditions is the basis for selective
cell eradication therapy in animals including humans.
STRUCTURE SECTION
[0064] One group of MIRAGE drugs is formed by derivatizing the DNA
binding molecules of Table 6 with Mossbauer absorber isotopes of
Table 7 where derivatizing constitutes the formation of a bond
between one or more Mossbauer atoms or a functionality to which one
or more Mossbauer atoms is bound and a DNA binding functionality.
The MIRAGE compounds retain the DNA binding property of the DNA
binding molecule, and contain at least one Mossbauer atom bound in
a fashion to permit the Mossbauer phenomenon to occur.
[0065] For example, the phenyl group of ethidium bromide (see Table
6 for the structure) is substituted with many organic groups of
alkyl, methyl, and phenyl without loss of the capacity to
intercalate because the substituents can be positioned in the
groove of the DNA molecule upon binding. A representative MIRAGE
pharmaceutical is ethidium bromide derivatived with a Mossbauer
isotope where the bond between the Mossbauer atom and the rest of
the molecule is of high enough energy to permit the Mossbauer
phenomenon to occur.
[0066] DNA binding molecules such as those in Table 6 are
derivatized with Mossbauer absorber isotopes such as those in Table
7 yielding MIRAGE pharmaceuticals. Some representative structures
are given with references to their synthetic pathway as
follows.
[0067] 1) A covalent bond directly between a Mossbauer atom and a
DNA binding molecule as prepared by the synthetic pathway for
compound 16 of the Exemplary Material.
[0068] 2) A chelating functionality covalently attached to a DNA
binding molecule and a chelation bond between the chelating
functionality and a Mossbauer atom as prepared by the synthetic
pathway for compound 153 of the Exemplary Material.
[0069] 3) A covalent or organometallic bond between a DNA binding
molecule and a Mossbauer organometallic molecule where bonding is
with the organic part of the organometallic molecule in the case of
a covalent bond and with the Mossbauer metal atom in the case of an
organometallic bond as prepared by the synthetic pathways for
compounds 100 and 25, respectively, of the Exemplary Material.
[0070] 4) An organic molecule covalently bound to a Mossbauer
nonmetal atom covalently bound to a DNA binding molecule as
prepared by the synthetic pathway for compound 38 of the Exemplary
Material.
[0071] 5) A nonmetal Mossbauer atom covalently bound to an organic
molecule covalently bound to a DNA binding molecule as prepared by
the synthetic pathway for compound 45 of the Exemplary
Material.
[0072] 6) A covalent bond between a DNA binding molecule and an
organic molecule to which a Mossbauer atom is attached by chelation
with a chelate covalently attached to the organic molecule as
prepared by the synthetic pathway for compound 89 of the Exemplary
Material.
[0073] 7) The DNA binding molecule having a coordinate or
organometallic bond directly with the Mossbauer atom as prepared by
the synthetic pathways for compounds 90 and 60, respectively of the
Exemplary Material.
6TABLE 6 DNA Binding Molecules Phenosafranine 1 Triostin A 2
Anthracycline glycosides (Daunorubicin) 3 Adriamycin 4 Nogalamycin
5 Mithramycin 6 Chromomycin A.sub.3 7 Phenoxazone
Antibiotics(Actinomycin D) 8 Acridine 9 Acridinylmethanesul-
phonanilide 10 Diacridine 11 Proflavine 12 Rhodanine 13 Acriflavine
14 8-Aminoquinoline 15 Chloroquine 16
2-Hydroxyethanethiolato(2,2',2"-terpyridine)- platinum (II) 17
Naphtholthiopheneethanolamine 18 Phenanthridine (Ethidium Bromide)
19 Phenanthroline 20 Ellipticene 21 2-Methyl-9-hydroxyellipticine
22 Tilorone 23 Thioxanthenone (Miracil D) 24 Psoralen 25 Bleomycin
26 Distamycin A 27 Netropsin 28 Hydroxystilbamidine 29 Berenil 30
DAPI 31 Hoechst 33258 32 Irehdiamine A 33 Dipyrandium 34
Leteoskyrin 35 Kanchanomycin 36 Mitomycin C 37
Pyrrolo-(1,4)-benzodiazepine Antibiotics (Anthramycin) 38
Sibiromycin 39 Nitrogen Mustard (Mechlorethamine) 40 Alkyl
Sulfonate (Bulsulfan) 41 Nitrosourea (Carmustine) 42 Ethylenimine
(Triethylene thiophosphoramide) 43 N-2-Acetylaminofluorene 44 Benzo
[a] pyrene 45 cis-Diamminedichloroplatinum (II) 46 Hedamycin
C.sub.41H.sub.52O.sub.11N.sub.2 Rubiflavin C.sub.23H.sub.29NO.sub.5
Stretonigrin 47 Neocarzinostatin
Ala--Ala--Pro--Thr--Ala--Thr--Val--Thr--
-Pro--Ser--Ser--Gly--Leu--Asp--Gly--Val--Val--Lys--Val--Ala
Gly--Ala--Gly--Leu--Gln--Ala--Gly--Thr--Ala--Tyr--Asp--Val--Gly--Gln--Cys-
--Ala--Ser--Val
Asn--Thr--Gly--Val--Leu--Trp--Asn--Ser--Val--Thr--A-
la--Ala--Gly--Ser--Ala--Cys--Asp--
Pro--Ala--Asn--Phe--Ser--Leu--Th-
r--Val--Arg--Arg--Ser--Phe--Glu--Gly--Phen--Leu
Phe--Asp--Gly--Thr--Arg--Trp--Gly--Thr--Val--Asp--Lys--Thr--Thr--Ala--Ala-
--
Cys--Gln--Val--Gly--Leu--Ser--Asp--Ala--Ala--Gly--Asp--Gly--Glu--
-Pro--Gly-- Val--Ala--Ile--Ser--Phe--Asn
[0074]
7TABLE 7 Absorber Source(s) .sup.176Yb -- .sup.176Tm .sup.159Tb --
.sup.159Gd .sup.159Dy .sup.165Ho -- .sup.165Dy .sup.165Yb
.sup.231Pa -- .sup.231Th .sup.231U .sup.157Gd -- .sup.157Eu
.sup.157Tb .sup.164Er -- .sup.164Ho .sup.164Tm .sup.168Er --
.sup.168Ho .sup.168Tm Tc.sup.99 -- Mo.sup.99 Gd.sup.156 --
Eu.sup.156 Tb.sup.156 Gd.sup.154 -- Eu.sup.154 Tb.sup.154
Er.sup.167 -- Ho.sup.167 Tm.sup.167 .sub.68Er.sup.170 -- Ho.sup.170
Tm.sup.170 Sm.sup.152 -- Pm.sup.152 Eu.sup.152m Eu.sup.152
Hf.sup.176 -- Lu.sup.176m Ta.sup.176 Lu.sup.176 Tm.sup.169 --
Er.sup.169 Yb.sup.169 U.sup.238 -- Pu.sup.242 Sm.sup.151 --
Pm.sup.151 Sm.sup.153 -- Pm.sup.153 .sub.62Sm.sup.154 -- Pm.sup.154
Eu.sup.154 Pr.sup.141 -- Ce.sup.141 Nd.sup.141 Os.sup.186 --
Re.sup.186 Ir.sup.186 Os.sup.188 -- Re.sup.188 Ir.sup.188
Hf.sup.177 -- Lu.sup.177m Ta.sup.177 Lu.sup.177 Lu.sup.175 --
Yb.sup.175 Hf.sup.175 Gd.sup.160 -- Eu.sup.160 Hf.sup.178 --
Lu.sup.178 Ta.sup.178 Gd.sup.158 -- Eu.sup.158 Tb.sup.158
Er.sup.166 -- Ho.sup.166m Tm.sup.166 Ho.sup.166 Cs.sup.133 --
La.sup.133 Ba.sup.133 Xe.sup.133 .sup.174Yb -- .sup.174mTm
.sup.174Lu .sup.174Tm .sup.67Zn -- .sup.67Zu .sup.67Ga .sup.172Yb
-- .sup.172Tm .sup.172Lu .sup.171Yb -- .sup.171Tm .sup.171Lu
.sup.170Yb -- .sup.170Tm .sup.170Lu .sup.131Xe -- .sup.131I
.sup.131Cs .sup.186W -- .sup.186Ta .sup.186Re .sup.184W --
.sup.184Ta .sup.184mRe .sup.184Re .sup.183W -- .sup.183Ta
.sup.183Re .sup.182W -- .sup.182Ta .sup.182Re .sup.180W --
.sup.180mTa .sup.180Re .sup.180Ta .sup.232Th(.sup.228Ra) --
.sup.236U .sup.236U -- .sup.236Pa .sup.240Pu .sup.236Np .sup.181Ta
-- .sup.181Hf .sup.181W .sup.125Te -- .sup.125Sb .sup.125I
.sup.147Pm -- .sup.147Pm .sup.147Eu .sup.149Sm (.sup.145Nd) --
.sup.149Pm .sup.149Eo .sup.101Ru -- .sup.101Tc .sup.101mRh
.sup.101Rh .sup.99Ru -- .sup.99Tc .sup.99mRh .sup.99Rh .sup.195Pt
-- .sup.195mIr .sup.195Au .sup.195IR .sup.195mPt
.sup.147Pm(.sup.147Sm) -- .sup.147Nd .sup.189Os -- .sup.189Re
.sup.189Ir .sup.237Np(.sup.233Pa) -- .sup.237U .sup.241Am
.sup.237Pu .sup.61Ni -- .sup.61Co .sup.61Cu .sup.83Kr -- .sup.83Br
.sup.83Rb .sup.83mKr .sup.193Ir -- .sup.193Os .sup.193Pt .sup.191Ir
-- .sup.191Os .sup.191Pt .sup.201Hg -- .sup.201Au .sup.201Ti
.sup.180Hf -- .sup.180Lu .sup.180mTa .sup.180Ta .sup.139La --
.sup.139Ba .sup.139Ce .sup.187Re -- .sup.187W .sup.234U --
.sup.234mPa .sup.238Pu .sup.234Np .sup.234Pa .sup.236U --
.sup.236Pa .sup.240Pu .sup.236Np .sup.239Pu -- .sup.239Np
.sup.243Cm .sup.239Am .sup.190Os -- .sup.190Re .sup.190Ir
.sup.197Au -- .sup.197Pt .sup.197Hg .sup.133Cs -- .sup.133Xe
.sup.133Ba .sup.160Dy -- .sup.160Tb .sup.160Ho .sup.166Er --
.sup.166mHo .sup.166Tm .sup.166Ho .sup.155Gd -- .sup.155Eu
.sup.155Tb .sup.73Ge -- .sup.73Ga .sup.73As .sup.178Hf --
.sup.178Lu .sup.178Ta K.sup.40 -- .sup.39K(n,r) .sup.40K Am.sup.243
-- Pu.sup.243 Bk.sup.247 .sup.145Nd -- .sup.145Pr .sup.145Pm
.sup.153Eu -- .sup.153Sm .sup.153Gd .sup.129I (.sup.129Xe) --
.sup.129mTe .sup.127I -- .sup.127Te .sup.127Ze .sup.119Sn --
.sup.119mIn .sup.119Sb .sup.119Tn .sup.57Fe -- .sup.57Mn .sup.57Co
.sup.151Eu -- .sup.151Sm .sup.151Gd .sup.129Xe -- .sup.129I
.sup.129Cs .sup.164Dy -- .sup.164Tb .sup.164Ho .sup.57Fe --
.sup.57Mn .sup.57Co .sup.161Dy -- .sup.161Tb .sup.161Ho .sup.162Dy
-- .sup.162Tb .sup.162Ho .sup.117Sn -- .sup.121Sb -- .sup.121mSn
.sup.121Sn .sup.121mTe .sup.121Te .sup.127I -- .sup.127Te
.sup.127Xe .sup.129I -- .sup.129Te .sup.129mTe .sup.133Ba --
.sup.133La .sup.145Nd -- .sup.145Pr .sup.145Pm .sup.145Pm --
.sup.147Sm -- .sup.147Pm .sup.147Eu .sup.153Eu -- .sup.153Sm
.sup.153Gd
EXEMPLARY MATERIAL
[0075] The materials which are listed below are representative
examples of possible MIRAGE drugs which can be synthesized by the
derivatization of known DNA binding materials and known Mossbauer
absorber isotopes from Tables 6 and 7, respectively to yield the
representative structures given in the Structure Section. The
following examples of reaction pathways are intended to be
exemplary and other pathways can be devised by one skilled in the
art. Furthermore, only a representative number of MIRAGE
pharmaceuticals are shown and a vast number of other MIRAGE
pharmaceuticals can be made by one skilled in the art following the
guide lines herein disclosed.
[0076] And, the disclosed MIRAGE pharmaceuticals and representative
structures disclosed in the Structure Section can be modified to
further MIRAGE pharmaceuticals to improve properties such as
permeability to cells, solubility, and enhanced selectivity by
addition of functional groups by one skilled in the art.
Representative functional groups include alkyl, cycloalkyl,
alkoxycarbonyl, cyano, carbamoyl, heterocyclic rings containing C,
O, N, S, sulfo, sulfamoyl, alkoxysulfonyl, phosphono, hydroxyl,
halogen, alkoxy, alkylthiol, acyloxy, aryl, alkenyl, aliphatic,
acyl, carboxyl, amino, cyanoalkoxy, diazonium,
carboxyalkylcarboxamido, alkenyl thio, cyanoalkoxycarbonyl,
carbamoylalkoxycarbonyl, alkoxy carbonylamino, cyanoalkylamino,
alkoxy carbonylalkylamino, sulfoalkylamino, alkylcarbonyloxy,
cyanoalkyl, carbonyloxy, carboxyalkylthio, arylamino,
heteroarylamino, alkoxycarbonyl, alkylcarbonyloxy, carboxyalkoxy,
cyanoalkoxy, alkoxycarbonylalkoxy, carbamoylalkoxy, carbamoylalkyl
carbonyloxy, sulfoalkoxy, nitro, alkoxyaryl, halogenaryl,
aminoaryl, alkylaminoaryl, tolyl, alkenylaryl, allylaryl,
alkenyloxyaryl, allyloxyaryl, allyloxyaryl, cyanoaryl,
carbamoylaryl, carboxyaryl, alkoxycarbonylaryl,
alkylcarbonyoxyaryl, sulfoaryl, alkoxysulfoaryl, sulfamoylaryl, and
nitroaryl.
GENERAL SYNTHETIC PATHWAYS
[0077] The following synthetic reactions are exemplary of general
synthetic reactions to be used to link a Mossbauer absorber atom
such as one from Table 7 with a DNA binding molecule such as one
from Table 6.
[0078] General reactions involving general organic chemistry such
as Wittig reactions, nucleophilic substitution reactions, tosylate
reactions, Friedel-Crafts alkylations and acylations, etc. appear
in the Exemplary Material and are generally known to one skilled in
the art. These same types of reactions can be used by one skilled
in the art to derivatize the DNA binding molecules of Table 6 to
produce the starting materials generally shown in the Exemplary
Material.
[0079] In some cases which are exemplified in the Exemplary
Material Grignard reagents are prepared of the DNA binding
molecules or derivatizing organic or organometallic molecules
containing a Mossbauer atom. The Grignard reagents can be prepared
by halogenation using a halogen gas and an initiator or by using a
halogen gas and a catalyst such as FeX.sub.3 where X is halogen
followed by reaction with magnesium. 48
[0080] For Grignard reagents as well as other compounds formed by
the above synthetic pathways, multiple side products of the
materials shown in the Exemplary Material are possible and are
often desirable. However, the reactions shown are intended to
exemplary of the types of reactions possible and are in no way
intended to be exhaustive.
General Reactions of Tin
R.sub.3SnCl+'RMgCl.fwdarw.R.sub.3SnR'
R.sub.3SnNR.sub.2'+R".fwdarw.R.sub.3SnR"
R"=aryl
[0081] (Comprehensive Organometallic Chemistry, Sir Geoffrey
Wilkinson, Editor, (1982), Vol. 12, Chapter 11) incorporated by
reference.
General Reactions of Antimony
[0082] 49
[0083] (Organometallic Compounds Methods of Synthesis Physical
Constants and Chemical Reactions, Michael Dubb, Editor, 2nd
Edition, Vol. III, (1968), pp. 653-925) incorporated by
reference.
General Reactions of Tellurium
[0084] 50
[0085] (Seebach, P.; Beck, A. L., Chem. Ber., 108, (1975), 314-321)
incorporated by reference.
General Reactions of Germanium
R.sub.3GcL+R'cl.fwdarw.R.sub.3GcR'
[0086] (Comprehensive Oraanometallic Chemistry, Sir Geoffrey
Wilkinson, Editor, (1982), Vol. 2, Chapter 10) incorporated by
reference.
General Reactions of Mercury
[0087] 51
[0088] (Comprehensive Organometallic Chemistry, Sir Geoffrey
Wilkinson, Editor, (1982), Vol. 2, Chapter 17) incorporated by
reference.
General Reactions of Iodine
[0089] 52
[0090] (Organic Chemistry, Fessenden, R. J., Fessenden, J. S.,
(1979) p. 728) incorporated by reference.
[0091] Representative examples of reactions which. yield DNA
binding MIRAGE pharmaceuticals are given in the following examples.
These examples are not to be taken as an exhaustive listing, but
only illustrative of the possibilities according to the present
invention.
EXAMPLE 1
[0092] Compound 5 is prepared as follows:
[0093] Trimethylstannylchloride 1, is reacted with imine 2, to form
aminotin compound 3. The aminotin 3, is reacted with psoralen 4 to
form the tin derivatized psoralen product 5 where the reaction
between 3 and 4 is as described in Comprehensive Organometallic
Chemistry, Sir Geoffrey Wilkinson, Editor, (1982), Vol. 2, p. 601,
incorporated by reference. Substitution at other aryl sites is
likely, and these products to are also expected to have utility.
53
EXAMPLE 2
[0094] Compound 8 is prepared as follows:
[0095] The Grignard reagent 6, which is an 8-aminoquinoline
derivative, is reacted with trimethylstannylchloride 7, to give the
tin derivatized quinoline product 8 where the reaction between 6
and 7 as described in Comprehensive Organometallic Chemistry, Sir
Geoffrey Wilkinson, Editor, (1982), Vol. 2, pp. 530-532
incorporated by reference. 54
EXAMPLE 3
[0096] Compound 11 is prepared as follows:
[0097] Actinomycin D, 9, is reacted with tetraalkyltin compound 10
to form the tin derivatized Actinomycin D product 11. 55
EXAMPLE 4
[0098] Compound 13 is prepared as follows:
[0099] Trimethystannylchloride is reacted with a Grignard reagent
derivative of Irehdiamine A to give product 13. 56
EXAMPLE 5
[0100] Compound 16 is prepared as follows:
[0101] A Grignard reagent of phenosafranin is reacted with
trimethylstannylchloride 7 to give product 16. 57
EXAMPLE 6
[0102] Compound 19 is prepared as follows:
[0103] Proflavine 17, is reacted with antimony trichloride in the
presence of HCl and NaNo.sub.2. The product is hydrolyzed and the
diazonium salt decomposed by reaction with NaOH and copper bronze
to yield the antimony derivatized acridine 19 according to the
method of O'Donnell, G. J., Iowa State Coll. J. Sci., 20, 34-6
(1945); CA 40. 4689; Ph.D. Thesis No. 760, submitted Aug. 23, 1944
at Iowa State College, incorporated by reference. 58
EXAMPLE 7
[0104] Compound 23 is prepared as follows:
[0105] 1,2-dihydroxybenzene is reacted with antimony trichloride in
the presence of HCl to give 2-chloro-1,3,2,-benzodioxastibole 21.
Nucleophilic condensation of hydroxy derivatized ethidium bromide
22, with compound 21 yields the antimony derivatized ethidium
bromide product 23. Substitution products at the amino groups are
also anticipated, and utility of these products is expected.
[0106] The synthetic pathway of product 23 is in general described
in The Heterocyclic Derivatives of Phosphorus, Arsenic, Antimony
and Bismuth, Frederick G. Mann, 2nd Ed., (1970) pp. 615-619,
incorporated by reference. 59
EXAMPLE 8
[0107] Compound 25 is prepared as follows:
[0108] 2-chloro-1,3,2-benzodioxastibole 21, is reacted with the
anthracycline, dozorubicin 24, to give the antimony derivatized
doxorubicin product 25. Substitution products of the sugar hydroxyl
groups are anticipated, and utility of these side products is
expected. 60
EXAMPLE 9
[0109] Compound 28 is prepared as follows:
[0110] Compound 26, 2,2'-biphenyldilithium is condensed with
aryldihalostibine 27, in benzene under reflux to yield the product
28. 61
EXAMPLE 10
[0111] Compound 31 is prepared as follows:
[0112] N,N'-dimethyl-4,41-diamino-2,2'-oxybis (phenylenemagnesium
bromide) is condensed with primary dihalostibine 27, in ether,
benzene, dioxane, or their mixtures to give product 31. 62
EXAMPLE 11
[0113] Compound 34 is prepared as follows:
[0114] Luteoskyrin 32, is reacted with
2-chloro-1,3,2-benzo-dioxastibole 21, to give the product 34.
Substitution products of other hydroxyl groups is expected and
utility is expected for many of these products. 63
EXAMPLE 12
[0115] Compound 38 is prepared as follows:
[0116] Phenyllithium is reacted with tellurium to give adduct 36
which is reacted with the phenanthridine 37 to give the tellurium
derivatized product 38 according to the reaction of Seebach, D.;
Beck, A. L., Chem. Ber. 108, (1975) pp. 314-321, incorporated by
reference. 64
EXAMPLE 13
[0117] Compound 40 is prepared as follows:
[0118] 1,8-dilithium naphthalene 39, is reacted with tellurium to
yield the product 40 according to the method of Marfat, A., et al,
Journal of the American Chemical Society, 9, (1977) pp. 255-256,
incorporated by reference. 65
EXAMPLE 14
[0119] Compound 42 is prepared as follows:
[0120] 3,6-dichloroacridine 41, is reacted with lithium followed by
tellurium and methylchloride to give the alkyl tellurium
derivatized acridine product 42. 66
EXAMPLE 15
[0121] Compound 45 is prepared as follows:
[0122] Kanchanomycin 43 is reacted with the dialkyl telluride 44 to
give the product 45. Additional products substituted at the
hydroxyl groups are anticipated, and utility of these products is
expected. 67
EXAMPLE 16
[0123] Compound 47 is prepared as follows:
[0124] Diacridine 46 is reacted with lithium followed by tellurium
and methylchloride to give the methyltellurium derivatized
biacridine product 47. 68
EXAMPLE 17
[0125] Compound 50 is prepared as follows:
[0126] Hycanthone 48, is reacted with the tellurium derivatized
phosphonium ylid 49 to give the alkyl tellurium derivatized
thioxanthenone product 50. 69
EXAMPLE 18
[0127] Compound 52 is prepared as follows:
[0128] Trimethylithium germanide 15, is reacted with
1,2-dichloroethane 30, and 2-chloloethyltrimethylgermanium 33, is
isolated from the product mixture which is reacted with Netropsin
to give the product 52. Other substitution products are
anticipated, and are expected to be of utility. 70
EXAMPLE 19
[0129] Compound 55 is prepared as follows:
[0130] The halogenated derivatize of ellipticine 53, is reacted
with trimethyllithium germanide 15, to give the product 55,
according to the method described in Comprehensive Organs Metallic
Chemistry, Sir Geoffrey Williams, Editor (1982) Vol. 2, Ch. 10,
incorporated by reference. 71
EXAMPLE 20
[0131] Compound 58 is prepared as follows:
[0132] Platinum compound 56 is reacted with 9-hydroxyquinoline in
acetic acid to give the product 58 according to the reaction
described by Kite, K. and Truter, M. R., J. Chem. Soc. (A), 1966,
207, incorporated by reference. 72
EXAMPLE 21
[0133] Compound 59, cis-diamminedichloro-platinum(II), is a
compound which binds directly to DNA.
[0134] It is synthesized using .sup.195Pt as described in Dhara, S.
C., Indian J. Chem., 8, (1970) p. 193, incorporated by reference.
73
EXAMPLE 22
[0135] Compound 60, 2-hydroxyethanethiolato(2,2',2"terpyridine)
platinum(II) intercalates directly into DNA.
[0136] It is synthesized using .sup.195Pt as described in
Jeannette, L. W.; Lippard, S. J.; Vassiliades, G.A. and Bauer, W.
R. (1974), Proc. Nat. Acad. Sci. USA, 71, 3839-3843, incorporated
by reference. 74
EXAMPLE 23
[0137] Compound 64 is prepared as follows:
[0138] Gold compound 61 is reacted with trimethylphosphonium-ylid
94, and dimethylchloromethylphosphoniumylid 54, to give product 62
as described by Schmidbaur, H., and Franke, R., Inorganica Chimica
Acta, 13 (1975) 79-83 (incorporated by reference) with the
exception that dimethylchloromethylphos-phoniummythylid is also
made present with trimethylphos-phoniummethylid and the desired
product is isolated from the reaction mixture. 62 is reacted with
phenanthridine 63, to give the product 64 where products with
substitution at the aniline nitrogens are anticipated and these
products are expected to have utility. 75
EXAMPLE 24
[0139] Compound 67 is prepared as follows:
[0140] Gold ylid compound 65 is reacted with nitrogen mustard 66 to
give the product 67. 76
EXAMPLE 25
[0141] Compound 72 is prepared as follows:
[0142] Pyrrole adduct 68 is mercurated by the reaction described in
Comprehensive Organometallic Chemistry, Sir Geoffrey Wilkinson,
Editor, (1982), Vol. 2, p. 871 (incorporated by reference) to give
adduct 69 which is reacted with oxalyl chloride to give acid
chloride 70. The acid chloride is reacted with amine 71 to give the
mercurated derivative of Distamycin A 72. 77
EXAMPLE 26
[0143] Compound 74, is prepared as follows:
[0144] Miracil 73 is mercurated to give product 74. Mixtures of
mercuration products are anticipated, and these products are
expected to be of utility. 78
EXAMPLE 27
[0145] Compound 76 is prepared as follows:
[0146] N-acetylaminofluorene 75 is mercurated to give product 76.
Mixtures of mercuration products are anticipated and these products
are expected to be of utility. 79
EXAMPLE 28
[0147] Compound 82 is prepared as follows:
[0148] Rutheniumtrichloride is reacted with cyclopentadiene to give
ruthenocene 77, which is acylated to give ketone 78. Both reactions
appear in Comprehensive Organometallic Chemistry, Sir Geoffrey
Wilkinson, Editor, (1982), Vol. 4, pp. 754-773, incorporated by
reference. Adduct 78 is reduced with lithium aluminum hydride to
give alcohol 79 which is reacted with p-toluenesulphonylchloride
123 to give tosylate 80. Adduct 80 is reacted with Adriamycin 81,
to give product 82. Substitution of other nucleophilic sites of
Adriamycin is anticipated, and these products are expected to be of
utility. 80
EXAMPLE 29
[0149] Compound 85 is prepared as follows:
[0150] Alkyl halogen derivative of ruthenocene 83 which is prepared
from 79 by treatment with phosphorous trichloride is reacted with
Sibiromycin 84, to give the product 85 which is the preferred
substitution product. 81
EXAMPLE 30
[0151] Compound 86 which is a coordinate compound of ruthenium and
phenanthroline intercalates DNA directly.
[0152] It is synthesized using .sup.99Ru as described in
Comprehensive Organometallic Chemistry, Sir Geoffrey Wilkinson,
Editor, (1982), Vol. 4, pp. 704-705, incorporated by reference.
82
EXAMPLE 31
[0153] Compound 89 is prepared as follows:
[0154] Quinacrine derivative 87 is reacted with a chloromethyl
derivative of diethlenetriaminepentaacetic acid 88, to give the
product 89 which is the preferred product of the possible mixture
involving substitution of the other nucleophilic sites. 83
EXAMPLE 32
[0155] Compound 90 is a coordinate compound of an actinide and
8-hydroxyquinoline which intercalates DNA directly.
[0156] 90 is synthesized using the indicated Mossbauer isotopes by
the procedures referenced in The Actinide Elements, K. W. Bagnall,
(1972) pp. 211-229, incorporated by reference. 84
EXAMPLE 33
[0157] Compound 93 is prepared as follows:
[0158] Alkyl halogen derivatied Bis(arene) tungsten compound 91,
which is synthesized as described in Comprehensive Organometallic
Chemistry, Geoffrey Wilkinson, Editor, (1982), Vol. 3, pp.
1356-1359 (incorporated by reference) with the modifications of
using benzene and methyl substituted benzene following the
synthetic route described in the above reference. The monomethyl
product is isolated from the product mixture and chlorinated to
give 91 or chloromethylbenzene is used in the referenced synthesis
with isolation of 91 which is reacted with alcohol derivative of
8-aminoquinoline 92, to give the product 93 where other
substitution products are anticipated, and utility is expected.
85
EXAMPLE 34
[0159] Compound 96 is prepared as follows:
[0160] Alkyl halogen derivatized bis(arene) tungsten compound 91,
is reacted with the carboxylate derivatized Anthramycin 95, to give
the product 96 which is the preferred product of the mixture which
could result from substitution at the hydroxyl groups. 86
EXAMPLE 35
[0161] Compound 100 is prepared as follows:
[0162] Osmocene 97, is prepared from osmiumtetrachloride and sodium
pentadienide as described in Comprehensive Organometallic
Chemistry, Geoffrey Wilkinson, Editor, (1982), Vol. 4, p. 1018,
incorporated by reference. Osmocene is acylated to give ketone 98
as described in the above reference. 98 is reacted with an ylid
derivative of acridine 99, to give the product 100. 87
EXAMPLE 36
[0163] Compound 103 is prepared as follows:
[0164] Methylalcohol derivatized osmocene 101, which is prepared
according to the method described in Comprehensive Organometallic
Chemistry, Geoffrey Wilkinson, Editor, (1982), Vol. 4, p. 1018
(incorporated by reference) is reacted with the tosylate derivative
of Mitomycin, C 102, to give the product 103. 88
EXAMPLE 37
[0165] Compound 106 is prepared as follows:
[0166] The diezonium derivative of Mithramycin 105, is prepared by
treating the amino derivative 104, with nitrous acid. The diazonium
derivative is reacted with aqueous potassium iodide to give the
product 106. 89
EXAMPLE 38
[0167] Compound 108 is prepared as follows:
[0168] The amino derivative of benzo[a] pyrene 107 is iodinated by
treatment with nitrous acid then aqueous potassium iodide. 90
EXAMPLE 39
[0169] Compound 110 is prepared as follows:
[0170] The amino derivatized quinoline antibiotic 109, is iodinated
by treatment with nitrous acid and aqueous potassium iodide to give
the product 110. The reaction is carried out under cold conditions
to prevent hydrolysis of the antibiotic. 91
EXAMPLE 40
[0171] Compound 112 is prepared as follows:
[0172] Amino derivatized naphthothiopheneethanolamine 111, is
iodinated by treatment with nitrous acid and aqueous potassium
iodide to give the product 112. 92
EXAMPLE 41
[0173] Compound 115 is prepared as follows:
[0174] Hafnium adduct 113 is reacted with 8-hydroxyquinoline 114 to
give the product 115 as described in Comprehensive Organometallic
Chemistry, Geoffrey Wilkinson, Editor, (1982), Vol 3, p. 565
(incorporated by reference) where 113 is prepared as described in
the same reference p. 569. 93
EXAMPLE 42
[0175] Compound 118 is prepared as follows:
[0176] The alkyl chloride hafnium compound 116 which is prepared by
preparing the methyl substituted bis(cyclo-pentadienyl) hafnium
dichloride as described in Comprehensive Organometallic Chemistry,
Geoffrey Wilkinson, Editor, (1982), Vol. 3, pp. 569-570
(incorporated by reference) which is chlorinated, and 116 is
isolated from the product mixture and is reacted with proflavine
17, to give the product 118 where the disubstituted product is
anticipated, and utility is expected. 94
EXAMPLE 43
[0177] Compound 121 is prepared as follows:
[0178] The alkyl chloride hafnium compound 116 is reacted with
Hoechst 33258 120, to give the product 121. 95
EXAMPLE 44
[0179] Compound 126 is prepared as follows:
[0180] Tantalum alcohol adduct 122 which is prepared by using the
synthetic route of Wilkinson, G. and Birmingham, J. M., Journal of
the American Chemical Society, (1954), Vol. 76, pp. 4281-4284
(incorporated by reference) with the exceptions that follow: In
addition to cyclopentadiene, methyl substituted cyclopentadiene is
used as a starting material to prepare the
methyl-bis-cyclopentadienyl chloride of tantalum. This compound is
chlorinated to yield 127 which is treated with hydroxide to yield
122. This alcohol is reacted with p-toluenesulphonylchloride 123 to
form the tosylate 124 which is reacted with the hydroxy derivative
of psoralen 125, to give the product 126. 96
EXAMPLE 45
[0181] Compound 129 is prepared as follows:
[0182] The alkyl chloride adduct of tantalum 127, is reacted with
Berenil 128, to give the product 129. Other substitution products
are expected, and utility is expected. 97
EXAMPLE 46
[0183] Compound 132 is prepared as follows:
[0184] Diphenyldilithium compound 130, is reacted with iridium
adduct 131 to give the product 132 by the procedure described by
Gardner, S. A., et al, Journal of Organometallic Chemistry, 60
(1973) 179-188, incorporated by reference. 98
EXAMPLE 47
[0185] Compound 137 is prepared as follows:
[0186] Iridium adduct 133 is reacted with diazonium adduct 134 to
give the o-metallated adduct 135 according to the method of
Farrell, N.; et al, Journal of the Chemical Society, Dalton,
Trans., 1977, 2124, incorporated by reference. 135 is reacted with
phenanthridine 136, to give the product 137 where other
substitution products are anticipated and utility is expected.
99
EXAMPLE 48
[0187] Compound 142 is prepared as follows:
[0188] Iridium compound 138 is reacted with Grignard reagent 139
followed by chlorination to give chloride adduct 140 according to
the procedure of Rausch, M. D. and Moser, G. A., Inorganic
Chemistry, Vol. 13, No. 1, 1974, pp. 11-13, incorporated by
reference. 140 is isolated from the reaction mixture and reacted
with the alkyl amine derivative of psoralen 141, to give the
product 142. 100
EXAMPLE 49
[0189] Compound 145 is prepared as follows:
[0190] Sodium hexachloroiridium (III) is reacted with benzo[h]
quinoline 143 to give 144 which is reacted with tributylphosphine
119, to give product 145 as described in Comprehensive
Organometallic Chemistry, Geoffrey Wilkinson, Editor, (1982) Vol 5,
p. 587, incorporated by reference. 101
EXAMPLE 50
[0191] Compound 150 is prepared as follows:
[0192] Iridium adduct 146 is reacted with phosphine compound 147 to
give o-metallated adduct 148 according to the procedure described
in Comprehensive Organometallic Chemistry, Geoffrey Wilkinson,
Editor, (1982), Vol. 5, pp. 578-587, incorporated by reference. 148
is acylated with an acid chloride derivative of acridine 149, to
give the product 150. Substitution at any of the other aromatic
sites can occur, and any of these side products are of equal
utility. 102
EXAMPLE 51
[0193] Compound 153 is prepared as follows:
[0194] The crown ether 18-crown-6 151, is reacted with Tilorone
derivative 152, to give the product 153. 103
EXAMPLE 52
[0195] Compound 158 is prepared as follows:
[0196] Acid chloride derivatized ferrocene 154, is prepared by
treatment of the ferrocene carboxylic acid whose synthesis is
described in Comprehensive Organometallic Chemistry, Geoffrey
Wilkinson, Editor, (1982), Vol. 4, p. 476 (incorporated by
reference) with oxalyl chloride; 154 is reacted with
1,3,4-butanetriol 155, followed by isolation of 156 from the
reaction mixture. Compound 156 is reacted with methylsulfonyl
chloride 157 to give the product 158 which is a derivative of
Bulsulfan. 104
Macromolecular MIRAGE Pharmaceuticals
[0197] MIRAGE imaging compounds include those that are generally
used in nuclear medicine and are massive in a recoil sense. When a
Mossbauer absorber atom is bound to a massive compound the
effective mass of the atom becomes the mass of the compound;
therefor the recoil energy is not transferred to the Mossbauer
atom, and resonant recoilless absorption which is the Mossbauer
phenomenon occurs. This effect is discussed in the Theoretical
Section. Examples of massive imaging compounds include the colloids
described in the Image Scanning Section where the radioactive atoms
are replaced with Mossbauer absorber atoms having a low internal
conversion coefficient or inorganic or organic molecules possessing
Mossbauer absorber atoms having a low internal conversion
coefficient where the substitute atoms or molecules form the same
type of bonding as the substituted radioactive atoms. Mossbauer
compound, .sup.197Au colloidal gold and antimony 121 sulfide
colloid are examples of this type of imaging compound.
[0198] Furthermore, MIRAGE compounds for diagnosis and therapy, in
addition to the compounds described in the Structure and Exemplary
Material Sections, are compounds containing Mossbauer absorber
atom(s) and are massive in a recoil sense or are compounds
containing Mossbauer absorber atoms which become incorporated into
the biological media as part of a massive compound which includes
polymer molecules such as proteins or crystalline structures such
as bone.
[0199] The inherently massive compounds are organic or inorganic
polymers, colloids, gelatin and dextran protected colloids, water
insoluble macroaggregates or crystals or combinations thereof which
contain Mossbauer absorber atoms which are covalently or jonically
bound to these carrier molecules or exist in a metallic, inorganic,
or organic form as occlusions or inclusions in these carrier
molecules. Polymer MIRAGE pharmaceuticals include proteins labeled
with Mossbauer absorber atoms such as .sup.57Fe hemoglobin,
.sup.127I and .sup.129I labeled thyroxine, .sup.119Sn, .sup.121Sb,
.sup.125Te, .sup.73Ge, .sup.127I, .sup.129I, and .sup.201Hg labeled
albumin and organic and inorganic polymers of the size range of
approximately 5-50 nm with Mossbauer absorber atoms bound
covalently, by chelation, by coordination, or electrostatically.
Examples include dibutyltin(119) dimethylacrylate, ruthenium(99)
bisbipyridine poly 4-vinyl-pyridine, poly[bis bipyridine
osmium(189) bis vinylpyridine], .sup.57Fe polyvinyl-ferrocene,
sulfonated polystyrene and Nafion and polymers containing
ethylenediaminetetra acetate and organo silane-styrene sulfonate
copolymers containing trapped cations of Mossbauer absorber atoms
including those cations of the lanthqnide, actinide and transition
metals.
[0200] The colloids include carboxyl, sulphate, phosphate,
hydroxide, and sulfide colloids containing Mossbauer absorber atoms
exclusively with the appropriate counter ion(s). Examples are
antimony 121 sulfide colloid and .sup.197Au colloidal gold. Or, the
colloids contain Mossbauer absorber atoms in metallic, inorganic,
or organic form as inclusions and occlusions. Carrier colloids of
this type include carboxyl, sulphate, phosphate, hydroxide, and
sulfide colloids and gelatin and dextran protected colloids and
micelles. Specific examples are Tc sulfur colloid, chromic
phosphate colloid, antimony sulfide colloid and dextran and gelatin
protected colloidals, yttrium hydroxide and colloidal gold,
containing inclusions or occlusions of cations of Mossbauer
absorber atoms including those cations of the lanthanide, actinide,
and transition metals. Micelles include soaps and carry organic
compounds containing Mossbauer absorber atoms such as benzene
labeled with .sup.125Te or .sup.119Sn.
[0201] Water insoluble macroaggregates include .sup.57Fe ferric
hydroxide and ferric hydroxide macroaggregate containing occlusions
and inclusions including the aforementioned cations. Crystals
include water insoluble microprecipitates of the approximate size
range of 5-50 nm of cations or anions of Mossbauer absorber atoms
such as .sup.125I.sup.- and .sup.129I.sup.-, AgI or silver halide
micropricipitates containing Mossbauer absorber atoms in metallic,
inorganic, or organic form as inclusions or occlusions in the
crystal including all of the aforementioned cations of the
lanthanides, actinides, and transition metals, and metallic and
inorganic forms of these isotopes.
[0202] Polymer compounds are prepared by attaching Mossbauer
absorber atoms or organic functionalities containing Mossbauer
absorber atoms to an organic polymer carrier by using the type of
reactions described in the General Synthetic Pathways and Exemplary
Materials Sections, or these types of reactions are used to attach
Mossbauer absorber atoms to monomers which are polymerized to
produce particles of the approximate size range of 5-50 nm by
reactions generally known to one skilled in the art. For the cases
where the Mossbauer absorber atoms are held by chelation,
coordinate, or electrostatic bonding, the atoms are exchanged into
the polymer backbone by reactions generally known to one skilled in
the art.
[0203] MIRAGE compounds which are inorganic polymers or colloids,
or micelles or water insoluble macroaggregates or crystals or
combinations thereof and consist of Mossbauer absorber atoms or
functionalities containing Mossbauer absorber atoms and counterions
or contain inclusions or occlusions of Mossbauer absorber atoms are
prepared by preparing the Mossbauer atoms or functionalities
containing Mossbauer absorber atoms and the other starting reagents
of the carrier compounds in the proper physical form and by
allowing them to form condensation nuclei and grow in solution and
by isolating the product by filtration or evaporation of the
solvent using reactions and techniques generally known to one
skilled in the art.
[0204] For example, sodium thiosulfate is treated with HCl and
technicium pertechnitate to give Tc sulfur colloid. And, gold
colloid is prepared by reducing a solution of gold chloride with
ascorbic acid or by heating gold chloride with an alkaline glucose
solution in the presence of gelatin. The product in each case can
be obtained by removing the solvent by vacuum distillation.
[0205] Additional MIRAGE compounds for diagnosis and therapy
include those compounds which contain Mossbauer absorber atoms
which become incorporated into biological molecules which are
massive in a recoil sense following administration of the
compounds. Such compounds which contain Mossbauer atoms in a form
to permit incorporation into proteins include water soluble ionic
compounds containing a Mossbauer absorber atom(s), as the cation or
anion such as those which dissolve in water to release
.sup.57Fe.sup.3+ which is incorporated into hemeproteins and
.sup.127I.sup.- or .sup.129I.sup.- which is incorporated into
thyroid compounds. Mossbauer atoms which can be incorporated into
bone as occlusions and inclusions include inorganic and metallic
forms of .sup.40 K, .sup.153 Gd, .sup.155 Gd, .sup.157 Gd, .sup.161
Dy, .sup.163 Dy, and .sup.149Sm. The corresponding MIRAGE
pharmaceuticals are water soluble ionic compounds, colloids,
crystals, or macroaggregates containing bone seeking Mossbauer
absorber atoms in ionic form or the MIRAGE pharmaceuticals are
carrier compounds such as colloids, crystals, or macroaggregates
possessing bone seeking Mossbauer absorber atoms in an inorganic or
metallic form as occlusions or inclusions. These compounds are
prepared as described previously.
PREPARATIONS AND ROUTES OF ADMINISTRATION
[0206] MIRAGE pharmaceuticals alone or combined with carrier
molecules can be administered orally, as sprays, intramuscularly,
intraveneously, or by subcutaneous, intra-articular, or
intra-arterial injection.
[0207] Medicinal formulations which contain one or more MIRAGE
compounds as the active compound can be prepared by mixing the
MIRAGE pharmaceutical(s) with one or more pharmacologically
acceptable excipients or diluents, such as, for example, fillers,
emulsifiers, lubricants, flavor correcting agents, dyestuffs or
buffer substances, and converting the mixture into a suitable
galenic formulation form, such as, for example, tablets, dragees,
capsules or a solution or suspension suitable for parenteral
administration. Examples of excipients or diluents which may be
mentioned are tragacanth, lactose, talc, agar-agar, polyglycols,
ethanol and water. Suspensions or solution in water, dextrose,
saline, or dimethyl sulfoxide can preferably be used for parenteral
administration.
[0208] Also, MIRAGE pharmaceuticals can be prepared as sterile
lyophilized powder to which a sterile solvent such as water or
dimethylsulfoxide is added. MIRAGE pharmaceuticals are also
prepared as a sterile lyophilized powder containing deoxycholate to
effect a colloidal dispersion of insoluble MIRAGE pharmaceutical.
These preparations are administered as injectables including
intramuscular and intravenous administration.
[0209] Topical MIRAGE pharmaceuticals can be prepared as a cream,
lotion, gel, ointment, and spray.
[0210] It is also possible to administer the active compounds as
such without excipients or diluents, in a suitable form, for
example in capsules.
[0211] MIRAGE pharmaceuticals can be packaged employing the usual
sorts of precautions which the pharmacist generally observes. For
example, the preparations may be packaged in light protecting vials
and may be refrigerated if necessary.
THE APPARATUS
[0212] The overall operation of the system may be exemplified by
the Co.sup.57/Fe.sup.57 Mossbauer pair as follows: the radioactive
source in the form of a thin film of material such as stainless
steel, copper, or palladium into which radioactive Co-57 has been
allowed to diffuse to provide a beam of highly homogeneous photons
having an average energy of 14.4 KeV. The homogeneity, or line
width .DELTA.E is 4.5.times.10.sup.-9 eV so that .DELTA.E/E is less
than 10.sup.-12. A filter selects the 14.4 KeV photon from the
other two photons of different energy.
[0213] The source is mounted on an accurately controlled mass
drive, which shifts the energy or frequency of the photon by the
Doppler effect. A wide variety of commercially available velocity
drives exist. A velocity of 1 mm/sec corresponds to an energy
change of 4.8.times.10.sup.-8 eV or more than ten line widths. The
arrangement 100 shown in FIG. 1 is one in which the source 50 is
mounted on a cone 62 of a speaker 60 and the speaker is driven so
that the relative position of the speaker coil increases and
decreases linearly with time (symmetric triangular wave form) at
approximately 5 Hz. Since the displacement of the speaker coil is
quite closely proportional to the input voltage, it is necessary to
provide a ramp voltage in order to produce a linear velocity. This
is accomplished by a triangular wave. A function generator 54 is
employed to produce an accurate, low frequency triangular voltage.
This voltage is applied to the speaker 60 through a power amplifier
56. In practice, it is necessary to employ considerable negative
feedback to produce an accurate linear velocity. This is
accomplished by coupling a second (or using a double voice coil 64)
speaker 66 to the drive speaker 60 with a rigid rod 52, and
providing the error signal from the second speaker (monitored by
oscilloscope 58) to the amplifier 56 through the integrator 68 as
shown schematically in FIG. 1. The source 50 is mounted on the rod
connecting the two speakers.
[0214] Since the source executes two velocity excursions, one at
positive and one at negative velocities, a synchronized shutter 70
can be used to block radiation during the nonresonant
excursion.
[0215] In addition to tuning the energy via a Doppler shift, the
emission energy of a Mossbauer source is continuously tunable by
driving it ultrasonically. A Mossbauer source can be adhered to a
piezo-electric transducer such as a quartz or barium titanate
transducer and driven at ultrasonic frequencies to produce an
infinite number of side bands in the emitted radiation which are
removed from the central, unshifted line by an integer multiple of
the ultrasonic frequency and the relative amplitudes of the side
bands can be varied by varying the power applied to the transducer.
The ultrasonic Mossbauer side bands can serve as a
variable-frequency energy source. The ultrasonic power is selected
so that essentially only the first side bands have appreciable
intensity and the ultrasonic driving frequency is chosen so that
the emission sidebands are of the desired energy. A
variable-frequency ultrasonic Mossbauer spectrometer based on this
principle is described by J. Mishory and D. I. Bolef, Mossbauer
Effect Methodology, Irwin J. Gruverman, Editor, Vol. 4, (1968) pp.
13-35, incorporated by reference.
[0216] In one embodiment, ultrasonic tuning of the gamma ray source
202 is shown in FIG. 7 where a source 204 of ultrasonic energy
energizes the gamma ray source 202 through an acoustic coupling
media to produce emission side bands of energy which is tunable by
changing the ultrasonic driving frequency.
[0217] The source, or emitter of radiation, can also include the
techniques known to Mossbauer spectroscopy of narrowing the line
width or absorbing unwanted Mossbauer lines. In addition, unwanted
radiation such as particle radiation can be absorbed by a filter
and wanted electromagnetic radiation can be separated from unwanted
electromagnetic radiation by addition of single frequency filter 80
shown in FIG. 2. The filter 80, receives source 50 radiation
through an input collimator 82 and enters a diffraction crystal 84.
Since the diffraction angle can be calculated (Bragg equation
n.lambda.=2d sin.theta.), the desired frequency is selected by
placement of a second output collimator 86 and the selection of a
crystal having an appropriate intranuclear layer distance (d).
[0218] In addition to the above-mentioned photon sources, the
photon emitters of Table 7 are useful in conjunction with the
correspondingly listed absorbers incorporated as pharmaceutical
agents.
[0219] Fluorescence, or nuclear emissions of the tissue components
excited at the Mossbauer frequency can be observed from the target
area. The dynamic range (signal-to-noise) can be enhanced by
viewing the subject 90 shown in FIG. 1 off-axis from the incident
radiation from the source, thereby eliminating the background level
from the source. Off-axis viewing is possible due to the continuum
of angles of fluorescent emission of the -target tissue component
at the Mossbauer frequency. Moreover, the frequency of the
fluorescence will coincide with the frequency of the source due to
the narrow spectrum of the Mossbauer resonance. Also, due to the
finite half life of the excited state, fluorescence can be
discriminated from exciting radiation by timing the arrival of the
signals.
[0220] Furthermore, fluorescence can be continuously monitored by
sensors such as 92 shown in FIG. 1 to give a characteristic plot of
the treatment effectiveness. A spatially distributed system of
multiple detectors such as proportional counters or scintilation
detectors, or lithium drifted silicon and germanium detectors where
each detector has a collimator at the aperture for the entry of
photons can localize the source of fluorescence. Photons must
travel in a straight line, and each collimator will only permit
photons propagating parallel to its axis to enter its detector.
Thus, the orientation of the axis of each detector's collimator
relative to the treatment field assigns a propagation direction for
source gamma rays called a ray path. The direction that gamma rays
are being administered assigns another, and signals from multiple
detectors at other orientations assign other ray paths. The
intersection of two or more ray paths gives the location of the
fluorescent source of gamma rays. In addition to the location of
the source of fluorescence which is the site of treatment, the
intensity at the detectors gives the intensity of treatment. A
control signal can be derived from the fluorescence, and combined
or processed by processor 94 of FIG. 1 according to the orientation
of detectors which record signal direction and the intensity of the
recorded signals to continuously control the source of fluorescence
to optimize the treatment. And, the apparatus could also be
combined with imaging equipment such as computed tomography,
magnetic resonance imaging, and ultrasound imaging which could be
used to determine the spatial location of the selected tissue to
provide the coordinates to be used with the fluorescent signal to
control the site of treatment.
[0221] In an alternate design, the imposed magnetic field may be
used to produce an energy transition for absorption of the
radiation without the necessity of a doppler shift of the gamma
source. The requirement of a magnetic field of predetermined
magnitude provided by current adjustment 108 of FIG. 2 and
direction can be accomplished by using Helmholtz coils or surface
coils discussed below. An exemplary apparatus is shown in FIG. 2
which uses Helmholtz coils 102, 104 where the patient 90 is
oriented along the z axis of the coils. A uniform field of
specified spatial dimensions can be created by varying the radius,
a, and the distance, z, between the coils. The field is saddle
shaped with the field at the saddle point being uniform and
strongly divergent from uniform immediately adjacent to the
saddlepoint. The equation for the field of the coils with the
current in the same direction is given as follows: 1 H 2 = NI 2 a 2
( a 2 + 2 2 ) 3 / 2 ( 2 )
[0222] Helmholtz coils can be placed in a longitudinal
configuration relative to the patient as shown in FIG. 2 and
transverse to the patient. A system of such Helmholtz coils are
used as described below to effect the field characterstics
necessary to cause selective absorption of Mossbauer radiation in
the desired location via the mentioned magnetic hyperfine splitting
and polarization effects.
[0223] Selectivity in treatment is achieved by imposing a magnetic
field gradient of sufficient steepness which exploits the
dependence of resonance energy on field strength so that resonant
absorption can be localized to specific dimensions (such as that of
a tumor) while maintaining nonresonant, and therefore
nonabsorptive, conditions in the surrounding nonselected tissue at
the energy of gamma rays imparted to the tissue. To achieve this
situation, the field gradient (field strength difference) must be
such that the induced resonant energy difference across the
selected space is one line width of the exciting gamma rays.
[0224] The parameters and calculations involved are discussed in
the Theoretical Section, below.
[0225] In one embodiment, a gradient field is produced by the
Helmholtz coils of FIG. 2 where the steepest gradient is produced
when the induced field from each coil opposes that of the other.
The field gradient produced by such configuration of Helmholtz
coils is given as follows: 2 G 2 = o NI 32 o a 2 ( 1 + 2 o 2 ) 5 /
2 ( 3 )
[0226] where Zo is the normalized source coordinate. Equation 3 and
equations for current distributions to produce desired field
gradients appears in U.S. Pat. No. 4,617,516 and its references
which are incorporated by reference.
[0227] In addition, a magnetic field of high field strength
gradient and/or with field lines which change from linear to linear
at a 90 degree (perpendicular) angle over a small spatial
displacement is produced by Helmholtz surface coils such as 110,
112, 114, and 132, 134 used in magnetic resonance imaging which
appear in FIGS. 3 and 4, respectively, and which appear in Nature,
Vol. 287 (1980) p. 736 incorporated by reference. Such surface
coils can typically achieve field strength gradients of 2000 gauss
per centimeter. The corresponding magnetic field lines are shown in
FIGS. 3A and 4A, respectively, where a saddlepoint is shown at 122.
Moreover, the gradient can be significantly increased in the case
where a very high coil current is sustained for a limited time to
prevent thermal damage to the coils. Surface coils can be used
singularly or in combination to effect the desired field
configuration and field gradient. And, the coil dimensions, number
of turns, current in each coil, and the relative position of the
coils can be adjusted to achieve the desired field. The
configuration of FIGS. 3, 4, 5 and 6 can be used with the apparatus
of FIGS. 1 and to achieve localization of the Mossbauer effect by
exploiting the dependence for resonance on the polarization and
propagation direction of the gamma ray for Mossbauer absorber
nuclei aligned by the presence of a magnetic field as described in
the Theoretical Section, below.
[0228] For example, the gamma ray could follow radially directed
field lines into the body and cut axial field lines deep in the
body at the location of the target tissue. As explained in the
Theoretical Section, when the gamma ray has the proper energy,
polarization and propagation direction, the nuclear transitions of
the Mossbauer atoms in the presence of the parallel field lines are
nonresonant with the administered gamma rays while those in the
presence of the perpendicular field lines are resonant for the
.DELTA.m=0 transition.
[0229] Combinations of Helmholtz coil pairs could achieve
selectivity by exploiting the conditions for resonance of gamma ray
energy, polarization and propagation direction. For example, the
pair of Helmholtz coils 102, 104 of FIG. 2 can be used to produce a
saddle shaped field where a uniform field parallel to the body axis
is produced at the saddle point. As described for a structure of
FIG. 6 having coils 152, 154, 156, 158, 160 and 162, the Volume 164
of the field saddle point can be made less than 1 mm.sup.3.
Furthermore, the transverse component of the magnetic field of a
surface coil is zero along its axis, and, the axial field is zero
in the equidistant plane of two matched Helmholtz surface coils
with opposite currents. The intersection of the axis of the coils
with the equidistant plane constitutes the saddle point of these
coils.
[0230] Spatial treatment selectivity can be achieved at the 1
mm.sup.3 volume level by applying surface coils in a configuration
of FIG. 2 such that the planes of the surface coils are parallel to
each other and perpendicular to the planes of the Helmholtz coils
102, 104 and such that the saddle point of the former superimposes
that of the latter. Treatment is carried out such that the gamma
rays propagate along the axis of the two surface coils 112 and 114
or along a radial field line in the equidistant plane of the two
surface coils 116 and 118. In both cases, the gamma rays would
encounter parallel aligned nuclei except at the intercept of the
saddle points where the rays would encounter nuclei aligned
transversely to the gamma rays' propagation direction, and
selective absorption will occur for the .DELTA.m=0 line by the
process described in the Theoretical Section.
[0231] An alteration of this scheme is to use two pairs of body
Helmholtz coils such as those shown in FIG. 2. Each pair is
matched, and the current is in opposite directions for one pair and
is in the same direction for the other pair. The field produced by
the former pair is greater than that produced by the latter.
Treatment is performed by administering the gamma rays in the
radial direction in the equidistant plane perpendicular to the axis
of all four coils. Selectivity is achieved by the polarization and
energy mechanism for the .DELTA.m=O transition as described in the
Theoretical Section because the field is predominantly radial
except where the gamma ray intersects the coils' axes where the
field is predominantly axial. This is because the field contributed
by opposing coils is radial with zero longitudinal component at
this point; whereas, the field of the coils with the current in the
same direction produce a large longitudinal component at this
point.
[0232] The axes of coils used to produce a magnetic field discussed
so far coincide with an axis which passes through the patient.
Another configuration of coils to produce a gradient field is two
external coils whose common axis does not intersect the body but is
aligned parallel to the axis through the body selected as the
gradient axis. With such a coil arrangement as demonstrated in FIG.
3, the depth at which the resonance conditions occur can be
selected by controlling the ratio of the currents in the two
coils.
[0233] The coils discussed thus far are Helmholtz coils, shown in
FIG. 4, which produce a field as shown in FIG. 4A. In FIG. 4A, the
flux pattern of the surface coil 132 is indicated by the lines 134,
and the field profile (i.e. lines of constant intensity) are
indicated by lines 136, 138, and 140.
[0234] The field is rotationally symmetric with respect to the axis
of the coil 132, but the component of the field directed
perpendicularly to the axis of the coil does not exhibit the same
rotational symmetry. For all points off axis, there is a non-zero
transverse component. Thus, the surfaces of constant transverse
field (whose traces in the plane of FIG. 4A correspond to lines
such as 136 to 140) are of somewhat distorted spherical shape. The
location of the selected tissue is between lines 142 and 144. In
practical terms, it is appropriate to consider the operation in
relation to layers of finite thickness corresponding to a resonant
condition along the field gradient of one linewidth; two such
layers are indicated at 146 and 148 in FIG. 4A.
[0235] A surface coil shown in FIG. 5 is wound in a fashion and
geometry which departs from that of a Helmholtz coil where the
field produced, FIG. 5A, by the former is considerably different
from the latter. In FIG. 5, a surface coil is shown which has
several turns 182, and 183 which enclose each other at least
partially and which are arranged at different geometrical points.
Each turn preferrably comprises substantially a single conductor
section or several conductor sections arranged in a group, the
current flows being opposite to each other in mutually adjacent
turns. The field produced by this coil is shown as FIG. 5A. In FIG.
5A, the field is shown in a plane perpendicular to the plane of the
coil with the Y axis being the axis of the coils. The location
coordinates are in arbitrary units and the lines of constant field
strength are given with the relative strength ratios entered along
the respective curves. Such a coil produces a steep field gradient
in strength and direction at depths from the surface which is
useful to realized selectivity by polarization and energy
mechanisms discussed in the Theoretical Section.
[0236] In a preferred method where fields are used to achieve
selectivity, treatment is carried out so that the propagation
direction of the gamma ray is along the steepest part of the field
gradient with regard to strength and/or direction such that no
volume containing nonselected tissue along the ray path satisfies
the resonance conditions for absorption of the gamma rays
administered to the selected tissue.
[0237] In addition, the apparatus possess a means to selectively
create absorption side bands of the Mossbauer absorber nuclei of
the selected tissue. Absorption side bands of Mossbauer absorber
nuclei can be produced by producing ultrasonic motion of the nuclei
along the direction of the incident resonant gamma rays. The shift
in energy and the amplitudes of the sidebands can be controlled by
controlling the ultrasonic driving frequency and the ultrasonic
power, respectively, as described by J. Mishory and D. I. Bolef,
Mossbauer Effect Methodology, Irwin J. Gruverman, Editor, Vol. 4,
(1968), pp. 13-35, incorporated by reference.
[0238] Selectivity is achieved by administering a narrow ultrasonic
beam which intersects the administered gamma ray beam at the
selected tissue site. The narrow ultrasonic beam is collimated or
focused.
[0239] The beam from an ultrasonic transducer is collimated to a
depth of D.sup.2/.lambda. where D is the transducer width and
.lambda. is the wavelength of the ultrasonic wave. Thus, for
producing a collimated ultrasonic beam to produce absorption side
bands at a depth z, the transducer size is given by equation 4. 3 D
op Z max ( 4 )
[0240] Focused beams are produced by the use of an acoustic lens or
by dynamic focusing through electronically controlled transducer
arrays. An acoustic lens is generally made of a plastic material
which has an acoustic propagation velocity greater than that of
water; thus, the refractive index is less than one, and the lens is
positive converging. For such a lens of spherical curvature, the
field amplitude is the Fourier transformer of the source
distribution at a depth of Z=f, the focal length. This results in
an effective lateral beam width at the focal plane of .lambda.f/D.
The velocity of sound in soft tissue is 1.5.times.10.sup.5 cm/sec
and the relationship between velocity, v, wavelength, .lambda., and
frequency, W, is as follows:
v=.lambda.w (5)
[0241] Thus, the width at a focal length depth of 10 cm of a 10 MHz
beam produced by a transducer of 1 cm width is 0.15 cm. The same
beam width relationship is achieved by electronically controlling a
transducer array. The output intensity and temporal relationship of
acoustic emission of the array elements are controlled to produce
interference effects to produce a focused ultrasonic beam.
Rectangular annular ring, concentric ring, and Theta arrays to
produced electronically focused ultrasonic beams in addition to
acoustic lenses and collimated transducers to produce narrow
directed ultrasonic beams are described in Medical Imaging Systems,
Albert Macovsik, (1983), pp 173-223, incorporated by reference.
[0242] Treatment is performed by directing the ultrasonic beam at
the selected tissue to excite a component of ultrasonic motion of
the Mossbauer absorber nuclei in the direction of the beam of the
administered gamma rays which intersects the ultrasonic beam in the
selected tissue. The ultrasonic beam creates absorption side bands
for Mossbauer nuclei in the selected tissue of energy shift equal
to the ultrasonic driving frequency. To achieve selectivity the
driving frequency is varied to shift the side bands to an energy
which is nonresonant with the nonselected tissue through which the
gamma rays of energy resonant with the side bands travel to the
selected tissue site. And, the amplitude of the excited absorption
side band of the Mossbauer absorber nuclei of the selected tissue
is maximized by controlling the power of the ultrasonic beam.
[0243] In one embodiment, ultrasonic tuning of the gamma ray source
202 is shown in FIG. 7. A source 204 of ultrasonic energy energizes
the gamma ray source 202 through an acoustic coupling media.
Alternatively, or in combination, a beam 206 of acoustic energy is
provided by a source 208 to cause the Mossbauer absorber atoms to
absorb the gamma rays at a target area common to both the path 212
of the gamma rays and the beam 206 of acoustic energy.
[0244] Treatment can be controlled by a microprocessor which
receives digitized input from peripheral sensors which follow
patient movement and displacement; velocity and acceleration of the
mass drive; shutter position; the magnetic field strength and
gradients; the frequency and voltage amplitude of the source
ultrasonic transducer; the adsorber side band producing ultrasonic
beam's direction, frequency, and intensity; and Mossbauer
fluorescence. Source activities of the order of 10.sup.3 ci are
possible so that treatment can occur over microseconds. Thus,
precise treatment can be effected by electronic control in the
presence of patient movement which occurs over times many orders of
magnitude greater than the processing times of high speed control
systems.
ADDITIONAL APPLICATIONS
[0245] MIRAGE drugs and therapy have many diverse applications in
addition to the treatment of cancer. For example, MIRAGE compounds
can be used for imaging and for treatment of any disorder which
involves the eradication of cells which are implicated in the
disorder. Disorders of the latter type include arthritis,
autoimmune disease, tissue transplantation rejection,
atherosclerosis, and AIDS.
IMAGE SCANNING
[0246] Radionucleotides, which have short half lives, on the order
of hours, and which are gamma-emitting isotopes, are used in
scintiscans to gain diagnostic information based on the
physiological properties of the pathological process. These
properties include differential uptake, concentration, or excretion
of the radionucleotide by normal versus diseased tissue. For
example, hepatic scintiscans are performed with gamma-emitting
isotopes that are extracted selectively by the liver, followed by
external radiation scanning of the upper abdomen. There are
basically three types of liver scans: the colloidal scan, which
depends on uptake of labelled colloid by Kupffer cells, where
.sup.198Au colloidal gold or .sup.99mTc sulfur colloid is most
commonly used; the HIDA or PIPIDA scans (.sup.99mTc-labelled
N-substituted iminoacetic acids) in which the dye is taken up and
excreted by hepatocytes, and the gallium scan, in which the
radionuclide .sup.67Ga is concentrated in neoplastic or
inflammatory cells to a greater degree than in hepatocytes. Hence,
a hepatoma or liver abscess will produce an area of reduced uptake
or "hole" using colloid or HIDA or PIPIDA scans, but there will be
an area of increased uptake or "hot spot" with a gallium scan. The
gallium scan is also helpful in diagnosing neoplastic infiltration
in the patient with cirrhosis, since the tumor will show increased
uptake, while fibrous bands will show decreased uptake. Another
major application of HIDA or PIPIDA liver scans is in the diagnosis
of acute cholecystitis, where failure of the nuclide to enter the
gall bladder is considered evidence of cystic duct or common bile
duct obstruction. The normal physiology involved is the uptake of
these compounds by the hepatocytes followed by excretion into the
biliary canaliculi and concentration in the gall bladder.
[0247] All Mossbauer isotopes are gamma emitters following
absorption of the same energy gamma photon, and most are stable
isotopes; therefore, they can be used in scintiscans. MIRAGE
imaging compounds are described in the Macromolecular MIRAGE
Pharmaceutical Section. As in the case of radionuclides,
information can be gained based on differential uptake, excretion,
or concentration as a consequence of the physiology of the
pathological process. But, Mossbauer scintiscans also provide the
ability to diagnose disease processes and to selectively image
different tissues based on the phenomenon of the differential
resonance frequency of the absorber isotope in different tissue
environments via mechanisms discussed under selectivity in the
Theoretical Section. Exciting the absorber isotope or isotopes by
causing a selected energy emission from the source along one axis
and simultaneously scanning with conventional Scintiscan
instrumentation along an axis different from the former axis
produces a Mossbauer Isotopic Resonance Absorption of Gamma
Emission (MIRAGE) scintiscan. Due to attenuation of the exciting
beam as a function of distance along the source axis, a correction
algorithm has to be used to process the data to produce an image of
the actual distribution of the Mossbauer isotope or isotopes in the
tissue.
ARTHRITIS, AUTOIMMUNE, AND TRANSPLANTATION REJECTION DISEASE
[0248] A successful treatment for rheumatoid arthritis is the
induction of necrosis of synovial cells of afflicted joints. For
example, intra-articular radioactive synovectomy using the
radionucleotide .sup.165Dy coupled with the massive inert carrier,
ferric hydroxide macroaggregate, has been shown by Sledge, et. al.
(Sledge, Clement, B., Clinical Orthopedics and Related Research,
No. 182, January-February 1984, pp. 37-40, incorporated by
reference) to be an effective means of reducing inflamation,
effusion and pain in patients with rheumatoid arthritis.
[0249] MIRAGE therapy provides selective cellular necrosis and
intra-articular MIRAGE synovectomy can be substituted for
intra-articular radioactive synovectomy to give the same
therapeutic effect, and by substituting stable Mossbauer absorber
isotopes for radioactive .sup.165Dy in the synovectomy treatment,
systemic radiation exposure from leakage is avoided.
[0250] Ferric hydroxide macroaggregate is massive in a recoil sense
and it an other massive inert carriers of 10.sup.8 daltons or
greater which were described previously would be effective in
permitting the Mossbauer effect to occur. MIRAGE therapy is
performed in this case with the previously mentioned massive inert
carrier molecules containing stable Mossbauer atoms such as
.sup.161Dy, .sup.163Dy, .sup.57Fe and .sup.119Sn in metallic,
inorganic or organic form which are administered by intra-articular
injection, and resonant Mossbauer radiation is administered to the
joints.
[0251] Other diseases which can be cured by inducing necrosis of
specific cell lines include autoimmune diseases and transplantation
rejection disease which includes graft versus host and host versus
graft. The cellular mediators for both of these diseases are
lymphocytes. The responsible cell lines can be eradicated by
synthesizing hybrid pharmaceuticals consisting of a protein and a
MIRAGE pharmaceutical where the MIRAGE pharmaceutical includes one
of those formed by derivatizing a DNA binding molecule of Table 6
with a Mossbauer absorber atom of Table 7 as described in the
General Synthetic Pathways and Exemplary Materials Sections, and
the protein includes a monoclonal antibody, the protein and MIRAGE
pharmaceutical are attached by a covalent bond such as a disulfide,
amide, ester, ether, amine, or carbon-carbon bond which is formed
by using existing functional groups or by placing functional groups
on the protein and MIRAGE pharmaceutical such as carboxyl, amino,
sulfide, halogen, or carbonyl and condensing the two entities
together by methods generally known to one skilled in the art. The
protein binds to surface of the target cell in a highly specific
manner. A monoclonal antibody to an antigen on the cell surface or
a hormone which binds to a receptor on the cell surface could serve
as the protein delivery molecule. The binding protein and the
attached drug are internalized together and the protein is degraded
releasing the MIRAGE drug which binds to a cellular target such as
the cells' DNA. The tissue is irradiated at the resonant frequency
of the pharmaceutical molecule bound to the cellular target. The
subsequently released Auger electrons causes irreversible damage to
the cell which is eliminated where the elimination serves a
therapeutic function.
MIRAGE DRUG FOR ATHEROSCLEROTIC OCCLUDED ARTERIES
[0252] MIRAGE therapy can be used to eliminate the cells
responsible for atheromas and involved in atherosclerosis.
[0253] The occlusion of arteries is the end result of the
atherosclerotic process which involves the following stages 1)
repeated injury which denudes the vessel of endothelium, 2)
deposition of platelets, fibrin and lipids, 3) inward migration of
smooth muscle cells and fibroblasts and 4) recanalization. The
cycle repeats until vessel occlusion occurs. Recanalization at this
point or lumen enlargement at a stage preceding occlusion requires
removal of smooth muscle and fibroblast cells without damage to
those cells of the same type which make up the vessel wall. This is
possible, however, with MIRAGE drugs which can kill cells which
have incorporated the drug by using levels of radiation which pose
no threat to health. Selectivity in this case is based on selective
uptake which is possible based on the fact that the smooth muscle
cells and fibroblasts which must be removed interface the blood
directly. A protein MIRAGE drug conjugate molecule which does not
cross endothelium and binds to the surface of the smooth muscle and
fibroblasts and not endothelial cells represents a selective drug
because binding can only occur with those cells which interface
blood directly. Specific binding proteins include monoclonal
antibodies to Platelet Derived Growth Factor (PDGF) receptor.
Binding is followed by internalization, degradation, and release of
the drug which binds to a susceptable biological target such as
DNA. Irradiation at the resonant Mossbauer absorption energy
[frequency] of the bound drug then eliminates the occluding cells
so that the vessel becomes patent.
MIRAGE AIDS DRUG
[0254] MIRAGE therapy can be made selective for the disease AIDS
where infected T cells are eradicated as a therapeutic
function.
[0255] Acquired immune deficiency syndrome (AIDS) has spread
exponentially and is predicted to reach epidemic proportions. A
conservative estimate of U.S. virus antibody positive individuals
is 10.sup.6, and the U.S. death rate in the near future based on
this figure is 54,000 deaths per year which compares with 30,000
deaths per year due to breast cancer. AIDS is a fatal disease with
no specific treatment, and development of a vaccine presents a
tremendous challenge for which there is no hope for success earlier
than 1990. Furthermore, the development of experimental drugs for
the treatment of AIDS has so far proceeded via a strategy
comparable to that utilized to develop antiviral drugs for viruses
such as Herpes. HIV, the causative agent of AIDS, behaves very
differently from other human pathogenic viruses because it destroys
the T cell segment of the immune system which normally is
responsible for controlling the elimination of a viral challenge.
In fact, HIV is unique as a retrovirus in that it is cytopathic.
Also, the biology of the virus is such that it can elude the immune
system during a latent phase and then activate to produce virus at
a tremendous rate before the host cell dies. This life cycle is a
consequence of a transactivating factor, tat III, and trs, a gene
product unique to HIV. The later protein controls the differential
splicing of the viral message at different points in the virus life
cycle. The complex in vivo behavior of HIV, which is characterized
by persistent infection in the human host, may depend on the
regulatory control of viral RNA splicing and translation. With a
capacity to express viral regulatory, but not structural proteins,
HIV infected cells may avoid the host immune response but would be
able to activate virion production quickly following additional
viral or cellular signals. Indeed, one manifestation of latency
seen in visna virus infection is characterized by viral RNA
synthesis without subsequent virion assembly. Likewise, HIV
infected but nonexpressing human T cells can be viably maintained
in long term culture, only to die when virus production is induced
by immunologic stimulation.
[0256] The cytopathic effect of HIV directly correlates with the
amount of viral envelop protein synthesized in infected cells.
Thus, efficient HIV production may require rapid viral protein
synthesis and assembly in the race between virion release and cell
death. The presence of large amounts of tat III at the time of a
trs-mediated splicing pattern switch to the synthesis of genomic
and envelop mRNAs may thus facilitate production of a very
cytopathic virus.
[0257] Antimetabolites and molecules which inhibit HIV enzymes can
only slow the relentless progress of this disease which destroys
the host's immune system by a T cell cytopathic life cycle. The
viral message exists in the host DNA and is replicated with the
host DNA. An infected cell represents a silent harbinger poised to
release infectious viral particles following the proper cellular or
viral signals. A reasonable approach to curing AIDS in an infected
individual is to destroy all such cells before the host's immune
system is inundated with virus and irreversibly compromised. MIRAGE
drugs represent agents which can selectively discriminate and
destroy HIV infected cells in the latent stage.
[0258] MIRAGE drug selectivity can derive from selective uptake, a
unique isomer shift, hyperfine splitting, and/or activation to
permit binding to a large target which permits the Mossbauer
phonomenon to occur. The enzymes involved in the life cycle of the
virus can be used to activate a drug only in cells harboring the
virus. Activation results in the-selective deposition of Mossbauer
radiant energy in the HIV infected cells using one of the mentioned
mechanisms. Based on the present knowledge of the biochemistry of
HIV, the exploitation of the activation of a unique chemical shift
is feasible. The mechanism is is explained in the Theoretical
Section.
[0259] Activation which involves changes in the chemical
environment at the Mossbauer atom of an intercalating MIRAGE drug
can be exploited as a method to selectively eliminate HIV infected
cells in the latent stage. Tat III is the only protein known to be
expressed during HIV latency. This protein is both a cytoplasmic
and a nuclear protein of about 14 kd. MIRAGE drugs to cure AIDS are
those that intercalate and also bind tat III. The later interaction
must change the electronic environment at the Mossbauer nucleus to
create a unique chemical shift. Intravenous and intrathecal
administration of such a drug followed by systemic irradiation at
the frequency of the created isomer shift will selectively kill
latent infected cells and interrupt the infectious process.
THEORETICAL SECTION PRINCIPLES OF RADIATION THERAPY
[0260] Ionizing radiation was found shortly after its discovery to
be capable of reducing the growth of human tumors. Unfortunately
the limitations of this modality were discovered as patients
developed catastrophic late complications. The radiotherapist must
perform treatment such that the balance of these opposing ends is
in favor of tumor ablation. The total story of the cellular
mechanisms involved remains elusive; however, many of the
principles involved can be appreciated from survival curves and a
basic understanding of the effect of radiation on cells and the
cellular response to damage.
[0261] Radiation therapy involves particle and electromagnetic
radiation which causes damage to both normal and cancer tissue. The
goal is to ablate the tumor while preserving normal tissue. The
principles involved are manifested in cell survival curves (See
FIGS. 8 and 9). Cells exposed to radiation reach a treatment
threshold and then are killed exponentially, the survival number
versus radiation dose is an exponential curve where a constant
fraction of the cells are killed per treatment. All tumors can be
controlled as the dose goes to infinity; however, it is the
limitation of tolerance of normal tissue not the ability to control
the tumor which is the guide to treatment. Thus, it can be
appreciated that a significant factor involved in a cure is the
first order rate constant, .alpha., and the initial burden N.sub.O
which appear in the first order rate equation below:
N=N.sub.)e.sup.-.zeta.Dose (6)
[0262] Critical is a reduction of the tumor burden, N, to a level
which is no longer overwhelming to the body's natural defenses.
[0263] Treatment with radiation can lead to a cure even though this
is a local modality which has no effect on distant micrometastases
despite the shedding of malignant cells by tumors which are below
the mass sufficient for diagnosis. Current data supports three
explanations for this inconsistency.
[0264] (1) Only a fraction of the clonogenic cells in the primary
retain their capacity to create metastases and nonclonogenic cells
may not continue to grow and invade at a distant site.
[0265] (2) There is evidence that the host has the ability to kill
a limited number of viable metastatic cells.
[0266] (3) The tumor mass influences its own metastatic potential.
Radiation therapy by diminishing the mass reduces the source of
clonogenic metastases and increases the host's ability to deal with
residual micrometastases by eliminating the tumor's adverse effect
on the host immune system.
[0267] The ideal in radiation therapy of malignant disease is
achieved when the tumor is completely eradicated and the
surrounding normal tissue of the treatment volume is structurally
and functionally intact. The important factor in the successful
treatment is the difference in the radiosensitivity of neoplastic
and normal cells which is the slope, .alpha., of equation 6. The
difference depends on the differential susceptibility to DNA
damage, differential repair capabilities, and differential
tolerance to unrepaired damage as well as the ability of normal
organs to continue to function well if they are only segmentally
damaged. In general, if surrounding tissue can tolerate twice the
radiation dose of a given tumor, then the tumor is radiosensitive.
Alternately, a tumor which extensively involves both lungs, and may
be cured with a dose of 3000 rads, cannot be treated effectively
with radiation therapy because of the greater radiosensitivity of
the surrounding lung tissue.
[0268] All tumors can be eradicated by treatment with sufficient
radiation. But, damage to normal tissue is dose limiting due to the
acute and late effects of radiation therapy. Acute effects include
esophagitis, pneumonitis, and diarrhea. They occur shortly after
treatment and limit the size of any given dose. Acute effects are
usually reversible and independent of the treatment history.
However, tissue has memory in that there is a threshold to the
total dose accumulated over the patient's history above which
unacceptable late effects occur. Late effects are total dose
limiting in radiation. They often progress with time and are
usually irreversible. These include fibrosis, necrosis, fistula
formation, non-healing ulcerations, and damage to specific organs
such as spinal cord transection or blindness. Normal tissues and
organs differ in radiosensitivity. The risk of complications
increases with dose, and if delivered by megavolt sources, in the
usual fractions, occurs when doses exceed the following: both lungs
1500 rads; both kidneys 2400 rads; liver 1500 rads; heart 3500
rads; spinal cord 4000 rads; intestine 5500 rads; brain 6000 rads;
bone 7500 rads. While the mechanisms of toxicity are not clear,
they do not appear to depend primarily on the rapid proliferation
of cell renewal tissue. Clinically they appear to depend much more
on the total dose and the size of the dose fraction. Acute
reactions may be misleading as a guide to long term effects. There
are a number of examples in radiation therapy where the total dose
has been increased, the size of the dose fraction increased or kept
the same while the interfraction period protracted to reduce acute
effects. Such maneuvers have resulted in unacceptable late
complications.
[0269] There are two hypotheses for the mechanism of late radiation
effects. One theory attributes late effects to the destruction of
connective tissue stroma. The pathogenesis of liver cirrhosis is
evidence that fibrosis can lead to organ destruction despite the
renewal potential of the cells of the organ. A variation on this
hypothesis is that the vasculo-connective issue is destroyed due to
endothelial cell injury which ultimately produces the late effects.
An alternate hypothesis suggests that both the acute and late
effects of radiation are due to depletion of the stem cell pool.
Acute effects depend on the balance between cell killing and
compensatory replication of both the stem and proliferative
compartments. The development of late effects requires that the
stem cells have only a limited proliferative capacity. Compensation
for extensive or repeated cell death may exhaust this capacity
resulting in eventual organ failure. This phenomenon can be
demonstrated for mouse hematopoietic lines. Stem cells can be
passed a finite number of times into irradiated mice until they
lose the ability to reconstitute the recipient's marrow.
[0270] Successful radiation therapy can be understood from the
dynamics of cellular responses to radiation. From the dynamic point
of view, the basic difference between a normal renewal tissue of
the body and a tumor is that in normal tissue there is an effective
balance between cell production and cell loss; whereas, in tumors,
cell proliferation exceeds cell loss. The normal renewal tissue can
be considered a hierarchy of three types of cells: Stem
cells.fwdarw.Maturing cells.fwdarw.Functioning cells.
[0271] The cell cycle of cancer cells are in general shorter than
those of normal tissue. It is found in general that irradiation
causes an elongation of the generation cycle of tumor cells while a
corresponding shortening of the cell cycle of normal cells is the
norm as the stem cells reconstitute the tissue. Dividing cells are
more susceptible as they possess more DNA and repair is more
difficult. Radiosensitivity of normal tissue may be partially
explained based on the magnitude of the regenerative response,
potentially lethal repair may not occur in rapidly dividing cells
as occurs in regenerating tissue. Also, experimental data indicate
that potentially lethal damage is repaired, and the fraction of
cells surviving a given dose of X-ray is enhanced if post radiation
conditions are suboptimal for growth. Both of these mechanisms
favor tumor cells over normal cells.
[0272] Thus, a major factor leading to a cure and which underlies
relative radiosensitivity is DNA repair capabilities. This
phenomenon of repair which is evidenced in the magnitude of the
survival curve shoulder accounts largely for the sparing effect on
normal tissue of the multi-fraction dose regimens that are so
commonly employed in clinical radiotherapy.
[0273] As with normal tissue, different tumors have a range of
radiosensitivity some being responsive to a few hundred rads, and
others incurable with as much as 10,000 rads, and this variation
can even exist within a specific tumor type. Furthermore,
radioresistance is selected for in the tumor population as normal
tissue regenerative capability declines. Thus, it can be
appreciated, from survival curves, as exemplified in FIGS. 8 and 9,
that necessary but not sufficient conditions for a cure via
radiation therapy are that the first order kinetics of cell kill
must be such that enough cancer cells are killed and the tumor does
not return to its original mass in the time interval necessary for
normal tissue to regenerate. And, the tumor volume is reduced to a
level which can be eliminated by the host's defenses before an
accumulated dose is reached which will ultimately produce
unacceptable late effects.
PHYSICS OF RADIATION THERAPY
[0274] Ionizing radiation exerts its effects on atoms primarily as
a function of the number of electrons. Biological molecules are
predominantly composed of atoms of less than atomic wt, 15, and
there is not a large difference in the magnitude of ionizations of
one element versus another. At a given dose, ionizing radiation
reacts with a fraction of any given molecule in its path.
Therefore, a fraction of proteins, and a fraction of DNA, etc, is
damaged. Therefore, even though it may be argued that the number of
ionizations in a cell may outnumber that of a critical species
present at low concentrations, only a fraction of that species is
damaged and the cell can survive if it can continue to produce
proteins, replicate, and divide with extreme fidelity. Thus, it is
evident from a theoretical point of view, and it is confirmed
experimentally that the critical element for survival for a cell is
to protect or reconstitute its genetic message. DNA has the ability
to rapidly repair most damage but lacks the ability to repair
double strand breaks which is the lethal event in radiation
therapy.
[0275] The radiation effects on particular molecules such as DNA,
are ascribed to two processes, direct and indirect action. By
direct action is meant the effects of energy directly in the target
molecule. By indirect action is meant effects of reactive species
formed in the surroundings that diffuse to the target and react
with it.
[0276] For DNA in dilute aqueous solution, the indirect effects of
irradiation are caused by the products formed by the action of
ionizing radiations on water which are the OH radical, the hydrated
electron, e.sup.- aq, the H atom, H.sub.2O.sub.2, and H.sub.2. The
major effective species in oxygenated solution is the OH radical.
This reacts chiefly with organic molecules either by adding to a
double bond, or by extracting an H atom from a C.sup.--H bond to
form H.sub.2O and a carbon radical. The OH radical reacts
essentially at a diffusion controlled rate with DNA and DNA
components.
[0277] Estimates of the extent of reaction indicates that of the
2.7 OH radicals produced per 100 ev of energy absorbed, at least
0.6 (20%) react with sugars to produce single strand breaks and
less than 2.1 (80%) with bases to produce modified bases. Cells
irradiated in the presence of radical scavengers have fewer single
strand breaks. There are many measurements of single strand breaks
in DNA from irradiated mammalian cells. Most fall in the range of 1
to 10.times.10.sup.-12 strand breaks in alkali per rad per dalton.
The direct and indirect effects being about equal. And, an
effective diffusion radius for the OH radical has been calculated
to be approximately 2.3 nm.
[0278] DNA double strand breaks could be produced by coincidence
between two independent events, by attack on two sugars by two
radicals formed in a single cluster by perhaps a high LET particle
or as a consequence of ionization of an inner shell electron in the
DNA molecule where it is estimated that perhaps 5% of the
ionizations in irradiated DNA may be associated with inner shell
excitations. Experimentally about one double strand break, a lethal
event, is observed per 20-40 single strand breaks.
DNA LABELING AND MECHANISM OF MIRAGE THERAPY
[0279] The mechanism and biological effect of direct damage to DNA
by particle or electromagnetic radiation can be assessed by
labeling the constituent nucleotides with beta emitters and alpha
emitters, respectively. The effects that arise from the decay of
beta emitters incorporated into the genetic material are single and
double strand breaks, base alterations, and inter-strand cross
linking. Single strand breaks can be efficiently repaired by living
cells, whereas double strand breaks are relatively inefficiently
repaired and are potentially lethal. In labeling experiments, the
predominant mechanism responsible for lethality appears to be
double strand breaks caused by internal radiolysis by primary or
secondary generated particles. For tritium labeled DNA the
probability of producing a double strand break per decay is less
than one, and the plot of cell survival versus decay demonstrates a
shoulder. Contrarily, .sup.125I produces between 2 and 12 double
strand breaks per decay event by a mechanism called an Auger
cascade, described below. This involves ejection of valence
electrons by an emitted gamma ray. The plot of cell survival vs.
number of decays demonstrates no shoulder indicative of a one hit
one target mechanism. Labeling experiments which label molecules
other than nucleotides demonstrate that lethality can be explained
by the proximity of the primary or secondary particle radiation to
the cell nucleus which is consistent with the lethal event being
nuclear damage. Lethality also involves probability as demonstrated
by the inverse relationship between the number of decay events
needed to kill a given cell type by a radioisotope and the number
of radiated electrons which it produces. For example, Bradley, et
al has demonstrated that .sup.125I is sixteen times as lethal as
tritium and Charleton and Booz calculated the electron spectrum
following decay of .sup.125I to determine in the mean 21 electrons
of high linear energy transfer are emitted per decay via Auger
cascade of electrons.
[0280] An Auger cascade is produced as part of a radioactive decay
pathway involving internal conversion. Internal conversion results
in ejection of inner shell electrons called conversion electrons.
Outer shell electrons can fill the vacancies and release energy.
The difference between the ionization energy of the inner shell
electron and that of the outer shell can be released by
transmission to another electron which is then ejected as an Auger
electron to produce a new vacancy. The process continues shell by
shell, until the valance shell is reached and thus leads to
multiple ionizations of the atom. Such a valency cascade, for
elements of low or medium atomic number, the Auger electrons have
energies up to a few KeV with a relatively high linear energy
transfer of 1 to 10 ev/nm. Since such electrons dissipate their
energy in materials of unit density within a distance of the order
of 10 to 100 nm they may efficiently damage molecules in the
nearness of the decay event. With regard to radiolabeling DNA, one
decay event of a radioactive atom such as .sup.125I of internal
conversion, followed by an Auger cascade which cause radiolysis and
double strand breakage is lethal to a cell. Radiation therapy is
far less efficient requiring approximately 10.sup.5 photons
absorption events per cell to produce the same lethal event. MIRAGE
therapy accomplishes the same end point as these modalities without
the use of radioactive atoms and with electromagnetic radiation
doses one million times less than that of conventional radiation
therapy. This is accomplished by utilizing phenomenon common to
electromagnetic radiation therapy and radioactive atomic DNA
labeling. MIRAGE therapy entails using Mossbauer atomic labeled
pharmaceuticals which bind to the genetic material of the target
cell and resonantly absorb gamma radiation to excite nuclear
transitions. Nuclear excitation produces a radioactive atom from a
stable atom, and the consequences are the same as for the case of
.sup.125I labeled DNA. Furthermore, this single event will kill the
target cell which is in contrast to conventional radiation therapy
where multiple improbable events must occur simultaneously to
produce a double strand break. 10.sup.5 photons by conventional
therapy versus one for MIRAGE therapy are necessary to eradicate
the target cell. Also, much less photon flux is needed for MIRAGE
therapy. The absorption cross-section for water the primary target
of conventional radiation therapy is approximately 10.sup.-25
cm.sup.2, whereas the resonant cross-section for Mossbauer
absorption is 10.sup.-17 cm.sup.2 which represents an eight order
of magnitude improvement. This increased efficiency permits cell
kill with radiation doses of one millionth that of conventional
therapy.
PHYSICS AND CHEMISTRY OF MIRAGE THERAPY WITH 12/29/W AS AN
EXAMPLE
[0281] The primary decay of the majority of radioactive nuclides
produces a daughter nucleus which is in a highly excited state. The
latter then de-excites by emitting a series of gamma ray photons
until it reaches a stable ground state. The Mossbauer effect occurs
when the gamma ray emitted during a rtransition to a nuclear state
is used to excite a second stable nucleus of the same isotope;
thus, giving rise to resonant nuclear absorption. This is an
extremely monochromatic event. The degree of monochromaticity can
easily be shown from the Heisenberg uncertainty principle. The
ground state of the nucleus has an infinite lifetime, and,
therefore, there is no uncertainty in its energy. The uncertainty
in the lifetime of the excited state is given by its mean life,
.tau., and the uncertainty in its energy is given by the width of
the statistical energy distribution at half height, .GAMMA.. They
are related by
.GAMMA..tau..gtoreq.h (7)
[0282] .tau. is related to the more familiar half-life of the state
by .tau.=1n2.times.t.sub.1/2. If .GAMMA. is given in electron volts
and t.sub.1/2 is in seconds, then 4 = 4.562 .times. 10 - 10 t 1 2 (
8 )
[0283] For a typical nuclear excited-state half-life of
t.sub.1/2=10.sup.-7 seconds, .GAMMA.=4.562.times.10.sup.-9 eV. If
the energy of the excited state is 45.62 KeV, the emitted gamma ray
will have an intrinsic resolution of one part in 10.sup.13. For
comparison, the maximum resolution obtained in atomic line spectra
is only about one in 10.sup.8. In fact, the line width is so narrow
that its energy can be Doppler shifted by driving the source at
moderate velocities or side bands in the emission energy can be
created by driving a stationary source at ultrasonic frequencies
where the energy of the side bands is continuously tunable by
varying the ultrasonic driving frequency. It is the capability of
shifting the energy of the source to cause resonant absorption in
an absorber atom incorporated as part of a pharmaceutical molecule
that permits the use of this phenomenon to selectively treat
disease such as cancer.
[0284] The Mossbauer effect is degraded by recoil energy of the
emitted and absorbed photon. This limitation can be circumvented by
binding the Mossbauer source and absorber atoms into a massive
lattice or molecular structure. The recoil energy is given as
follows: 5 E R 2 = E r 2 2 Mc 2 ( 9 )
[0285] This equation indicates that as the mass of the structure
into which the Mossbauer atom is incorporated goes to infinity the
recoil energy goes to zero. To accomplish this the source atoms are
incorporated into a lattice or metal and the absorber is
incorporated into a pharmaceutical which binds to a massive
molecule or is incorporated into a biological lattice. Examples
include DNA and bone matrix, respectively. For the former case, the
Mossbauer atom is bound to a pharmaceutical by covalent, chelation,
or coordinate bonds and the pharmaceutical molecule binds to DNA by
hydrogen or covalent bonding, electrostatic interactions, or
intercalation.
[0286] Structures which bind to DNA to form extremely stable
complexes with duplex DNA by hydrogen bonding and electrostatic
interactions and which could be used as part of a MIRAGE drug
include netropsin, distamycin A, and anthramycin. And intercalating
structures which could be used to produce a MIRAGE drug include
ellipticinium, quinacrine, actinomycin, mithramycin, ethinium,
adriamycin, acridine orange, nogalamycin, propidium,
anthracyclines, psoralen, duanarubicin, bithiazole, olivomycin,
chromomycin A.sub.3, acridine, chloroquine, quinine, 8
amino-quinolines, quinacrine, proflavin, bleomycins, phleomycins,
mefloquine, mitoxantrone, and others which represent modification
of the mentioned basic molecular structures.
[0287] See Table 6 for the structure of DNA binding molecules and
see FIG. 10 for a diagram of MIRAGE drug 12/29/W and its mechanism
of intercalation.
[0288] Degradation of the Mossbauer effect via recoil of the entire
atom can be prevented by bonding it to a massive object; however,
nuclear recoil energies are of the order of magnitude of
lattice-vibration phonon energies and the Mossbauer effect can be
degraded if the recoil energy excites one of the quantized
vibrational levels. The probability that one emission or absorption
event will occur without vibrational degradation is given by the
parameter f which is known as the recoilless or recoil-free
fraction. To increase the relative strength of the recoilless
resonant process, it is important that f be as large as possible.
The recoilless fraction f can be related to the vibrational
properties of the crystal lattice by 6 f = ( - E r 2 x 2 ( c ) 2 )
( 10 )
[0289] where <x.sup.2> is the mean-square vibrational
amplitude of the nucleus in the direction of the gamma ray. From
the form of the exponential, f will only be large for a tightly
bound atom with a small mean-square displacement and for a small
value of the gamma ray energy, E.sub..gamma.. F can be increased
for the source by cryostatically cooling it, and f can be increased
for the absorber atom which is part of a pharmaceutical by
increasing the bond strength of the atom with the remainder of the
pharmaceutical molecule.
[0290] As described previously, Auger cascades in DNA binding
pharmaceuticals cause DNA radiolysis and concomitant death of the
cells in the target tissue. The equation which relates the number
of internal conversion events with concomitant Auger cascade to
nuclear parameters is given as follows:
B=.theta..sub.ofn.phi. (11)
[0291] where B is the number of internal conversion events,
.theta..sub.o is the Auger cross-section, f is the recoilless
fraction, n is the number of Mossbauer atoms, and .phi. is the
photon flux. .theta..sub.o is entirely determined by nuclear
parameters and is given by the following equation: 7 O c = 2 ( c E
r ) 2 2 Ie + 1 2 Iq + 1 1 + ( 12 ) O ( E ) = O o ( 2 ) 2 ( E - E r
) 2 + ( 2 ) 2 ( 13 )
[0292] where equation 12 gives the maximum cross-section,
.theta..sub.o, at E=E.sub.o and equation 13 is the cross-section
for resonant absorption. Ie and Ig are the nuclear spin quantum
numbers of the excited and ground states, .GAMMA. is the line
width, and .alpha. is the internal conversion coefficient which is
the ratio of the number of conversion electrons to the number of
gamma ray photons emitted. To generate an effective MIRAGE drug, a
Mossbauer atom with a large Auger cross-section which emits
multiple Auger electrons of high linear energy transfer of the
range 1-10 ev/nm is used. Examples of isotopes with large Auger
cross-sections are given in Table 8 where the value for .sup.57Fe
is given as 2.2.times.10.sup.-17 cm.sup.2.
[0293] The number of targets, n, is dependent on the binding
constant of the drug with DNA. The bithiazale group of Bleomycin
has a Kd of the 10.sup.6 which results in one Bleomycin molecule
bound per eight nucleotides. This represents at least 10.sup.9
target atoms per cell. Intercalating drugs such as biacridines have
Kd's of the order of 10.sup.11; thus n can be made even larger.
And, drugs which use different modes of binding can be used in
combination. For example, the DNA molecule can become saturated
with intercalated drugs but retain the ability to bind a drug which
binds by a mode different than intercalation. An example is
Netropsin which binds externally to the DNA molecule by
electrostatic interactions. N can be increased by using a
combination of drugs such as acridine and Netropsin analogues where
binding is by intercalation and electrostatic interactions,
respectively.
8TABLE 8 Representative Mossbauer Isotopes with Parameters
Favorable for Cancer Therapy Recoil Free Fraction of Crystal Half
Life Gamma Half Life /Auger Mossbauer Absorber of Ground Isotope
Ray of Excited (Cross- Line Recoil T = 300.degree. State(yr)/
Abundance Energy State Section) Width Energy O.sub.d = 200 Isotope
Mode of Decay (%) (keV) (NS) (10.sup.-20cm.sup.2) (mm/sec)
(10.sup.-3ev) (%) Potassium 40 1.28 .times. 10.sup.9B .012 29.5
4.25 6.6/196 2.177 11.7 .6 Iron 57 2.14 14.4 97.8 8.21/2218 .194
1.956 44 Tin 119 8.58 23.87 17.75 5.12/716 .6456 2.57 33 Antimony
121 57.25 37.15 3.5 11.1/217 2.104 6.12 7 Tellurium 125 6.99 35.46
1.48 13.5/361 5.209 5.39 10 Iodine 127 100. 57.6 1.91 3.78/77.5
2.486 14.0229 .2 Iodine 129 1.7 .times. 10.sup.7B 0. 27.77 16.80
5.1/199 .586 3.2089 25 Xenon 26.44 39.58 1.01 12.3/288 6.84 6.5187
6 Samarium 149 4 .times. 10.sup.14.alpha. 13.83 22.4940 7.12
50./372 1.708 1.8 45 Europium 151 47.82 21.53 9.7 30./658 1.3 1.648
46 Gadolinium 155 14.73 60.01 .134 8./90.66 34.02 12.47 .5
Gadolinium 157 15.68 54.54 .187 11.87/114 26.82 10.17 1.2
Gadolinium 157 15.68 64.0 460. .7/37 .009 14.004 .5 Terbium 159
100.0 57.955 .10 9.36/98.5 44.9 11.355 .8 Dysprosium 161 18.880
25.655 28.2 2.9/275 .378 2.1944 38 Dysprosium 161 18.880 43.83 .78
4.32/137 3.00 6.4040 5 Dysprosium 163 26. 39 Ytterbium 171 14.31
66.72 .87 11.2/100.6 4.7127 13.97 .2 Tungsten 183 14.40 46.4837
.184 40./220 31.98 6.3379 6.54 Osmium 189 16.1 36.22 .500 80./92
15.105 3.7259 20.2 Mercury 201 13.22 32.19 .200 60./117 42.49
2.7672 30.4 Thorium 232 1.41 .times. 10.sup.10.alpha. 0. 49.369
.345 300./507 16.06 5.639 9 Uranium 238 4.5 .times. 10.sup.9.alpha.
99.27 44.915 .2250 660./602 27.069 4.5499 14.3 Neptuniun 237 2.14
.times. 10.sup.8.alpha. 0.00 59.5370 68.3 1.12/36 .0672 8.0283 3.1
.alpha. = alpha B = beta
[0294] MIRAGE drugs must be designed such that they have a high
recoilless fraction which is a function of the vibrational energy
of the bond linking the Mossbauer atom to the pharmaceutical. The
energy of molecular vibrations has a range of 5-50 KJ; whereas
lattice vibrational energies range between 0.5 to 5 KJ. As a
comparison, the vibrational energy of Fe metal at room temperature
is 1 KJ. To achieve a high recoilless fraction the vibrational
energy should be an order of magnitude greater than the recoil
energy which is 0.1 KJ for .sup.57Fe. For example, the vibrational
energy of Fe metal is an order of magnitude greater than the recoil
energy, and f for .sup.57Fe metal at room temperature is 0.7. F
should be higher for .sup.57Fe/Bleomycin because K.sub.D for the
coordination of iron with Bleomycin is 10.sup.9 which gives a
.DELTA.G of approximately -50 KJ and a vibrational energy of
approximately 5 KJ by thermodynamic calculations.
[0295] Since covalent bonding yields higher vibrational energies,
the Mossbauer atom should be covalently bound to the intercalating
function. Many of the Mossbauer isotopes form covalent bonds with
organic molecules. Examples include Mossbauer isotopes of tin,
antimony, tellurium, iodine, germanium, and mercury. Lanthanide
Mossbauer isotopes such as gadolinium, dysprosium, samarium, and
europium form chelation compounds with K.sub.D's of the order of
10.sup.23. Mossbauer isotopes can also be involved in
organometallic bounding such as occurs between iron and
cyclopentadiene and between osmium and cyclopentadiene in ferrocene
and osmocene, respectively. Vibrational energies for these
compounds is approximately one tenth the bonding energies which are
of the order of 300 KJ/mole. Thus, the recoilless fraction for
pharmaceuticals involving this bonding would be high. Examples of
MIRAGE pharmaceuticals are given in the Exemplary Material
Section.
[0296] Using the previously described nuclear and thermodynamic
parameters, a calculation of the dose necessary to achieve
therapeutic efficacy can be calculated for 12/29/w and compared to
the actual experimental effect which appears in the Experimental
Section. For Fe the Auger cross-section is 2.2.times.10.sup.-17
cm.sup.2 where .alpha.=10 and internal conversion occurs greater
than 90% of the time. Greater than 10 conversion electrons and
Auger electrons are emitted on average per transition as appeared
in FIG. 11. The binding constant of Bleomycin to DNA is 10.sup.6
which corresponds to the number of targets, n, aqual to 10.sup.9.
The free energy of binding of iron to Bleomycin is 50 KJ which
predicts a recoilless fraction, f, of approximately one. One
nuclear excitation event followed by internal conversion produces a
lethal hit. The necessary photon flux to effect this event is
calculated using equation 11 as follows: 8 1 ( 10 9 ) ( 1 ) ( 2.2
.times. 10 - 17 ) = = 4.5 .times. 10 7 photons cm 2
[0297] The dose due to this photon flux is calculated as follows
for the 14.4 KeV gamma ray of a .sup.57Co source using the equation
from FIG. 12 where 70% of the energy is absorbed in 1 cm: 9 Dose =
( .7 ) ( 4.5 .times. 10 7 photons ) ( cm 2 ) ( 14.4 .times. 10 3 ev
) ( photon ) ( 1.6 .times. 10 - 19 J ) ( ev ) ( 10 7 erg ) ( 1 J )
.times. 1 rad 100 erg g = 7 m rad
[0298] This can be compared with the m rad levels of Mossbauer
radiation which were found to be effective in the experiments
indicated in the Experimental Section.
ADDITIONAL PHARMACEUTICALS
[0299] Exploitation of the Mossbauer effect permits drugs which
will eradicate target cells using levels of radiation which are
comparable to background levels and well below levels that are
necessary to cause acute or late effects of radiation therapy.
Furthermore, MIRAGE therapy is a modality whereby the side effects
of chemotherapy can be eliminated. MIRAGE drugs are designed such
that they bind to targets such as DNA and the therapy is conducted
in such a manner that the Mossbauer effect will be caused to occur
in the space occupied by the target cells, but not to a significant
extent in the nontarget cell locations by mechanisms to be
described below. The binding can be nontoxic. Representative
nontoxic structures are psoralens used for the treatment or
psoriasis, quinacrine and acridine drugs used for parasitic
diseases, quinoline drugs used for the treatment of malaria,
thioxanthenone drugs used for the treatment of Schistosomiasis, and
Tilorone, an antiviral drug, (see Table 6 for structures).
[0300] The parameters involved in fabricating a pharmaceutical
using other Mossbauer isotopes are the same as those discussed for
.sup.57Fe. For example .sup.119Sn, .sup.121Sb, and .sup.125Te can
be covalently linked to intercalating molecules. The bond energies
are typically 400-500 KJ/mole which implies vibrational energies of
40-50 KJ/mole. This is well above an order of magnitude the recoil
energies which are 0.25 KJ/mole, 0.59 JK/mole, and 0.52 KJ/mole,
respectively. Thus, a recoilless fraction, f, of approximately one
is predicted. The Auger cross-sections from Table 8 are
7.16.times.10.sup.-18 cm.sup.2, 2.17.times.10.sup.-18cm.- sup.2 and
3.61.times.10.sup.-18cm.sup.2, respectively. .sup.119Sn,
.sup.121Sb, and .sup.125Te are approximately the same atomic number
as .sup.125I where the latter radioactive isotope ejects 21
electrons during an Auger cascade involving the K shell. These
former Mossbauer isotopes are predicted to eject the same number of
electrons because internal conversion involves K and L shells as
demonstrated in FIGS. 13, 14, and Synthetic pathways for exemplary
MIRAGE drugs incorporating the Mossbauer isotopes .sup.119Sn,
.sup.121Sb, and .sup.125Te and other isotopes from Table 7 appear
in the Exemplary Material Section.
SELECTIVITY
[0301] Selective killing of selected cells with sparing of
nonselected cells can be achieved by several mechanisms:
[0302] 1. The use of pharmaceuticals where their chemical and
physical properties exploit biological phenomena.
[0303] 2. The use of pharmaceuticals which have a different isomer
shift, quadrapole hyperfine splitting, or magnetic hyperfine
splitting in selected cells versus nonselected cells.
[0304] 3. Applying magnetic or electric fields in the space
occupied by the selected tissue so that a hyperfine line is created
for the selected tissue which is absent for the nonselected
tissue.
[0305] 4. Polarization of the incident gamma rays with resonant
polarization of the absorbers in the selected tissue and not in the
nonselected tissue.
[0306] 5. Applying a collinated or focused ultrasonic beam along a
line path that intersects the administered gamma rays at the
selected tissue site where the former beam excites a component of
ultrasonic motion of the Mossbauer absorber nuclei in the direction
of the latter beam to produce absorption side bands and where the
gamma rays of the second beam are of energy resonant with the side
bands.
[0307] For case 1
[0308] MIRAGE therapy can achieve selectivity in the case of cancer
therapy in animals including humans via exploiting known selective
uptake by cancer cells of compounds such as Bleomycin, cationic
lipophilic dyes such as Rhodanine, hematoporphryins, and monoclonal
antibodies. In these cases, a Mossbauer isotope or MIRAGE
pharmaceutical is bound to the compound known to be selectively
taken up by the cancer. In contrast to chemotherapy, the
selectivity need only be relative to other cell types in the
Mossbauer radiation field.
[0309] The MIRAGE pharmaceutical includes those formed by
derivatizing a DNA binding molecule of Table 6 with a Mossbauer
absorber atom of Table 7 as described in the General Synthetic
Pathways and Exemplary Materials Sections. The carrier and MIRAGE
pharmaceutical are attached by a covalent bond such as a disulfide,
amide, ester, ether, amine, or carbon-carbon bond which is formed
by using existing functional groups or by placing functional groups
on the carrier and MIRAGE pharmaceutical such as carboxyl, amino,
sulfide, halogen, or carbonyl and condensing the two entities
together by methods generally known to one skilled in the art.
[0310] Colloids such as those of gallium are known to be
concentrated by certain types of cancer cells and the same
phenomenon is predicted for certain colloids of Mossbauer isotopes
comprising massive inert carriers such as those described in the
Macromolecular MIRAGE Pharmaceutical Section. Carriers of 10.sup.8
daltons or greater are expected to be effective in permitting the
Mossbauer effect to occur. Also, many Mossbauer isotopes including
metallic and inorganic forms are capable of being incorporated into
biological matrices including bone which is useful for the
treatment of metastatic bone cancer. Examples include .sup.40K,
.sup.153Gd, .sup.161Dy, .sup.163Dy, .sup.149Sm, .sup.151Eu,
.sup.155Gd, and .sup.157Gd compounds described previously in the
Macromolecular MIRAGE Pharmaceutical Section. And, as further
described in the mentioned section, Mossbauer isotopes can be
incorporated into other biological molecules. For example,
Mossbauer isotopes .sup.127I and .sup.129I can be incorporated into
thyroid hormones and the precursor molecules of thyroid hormones.
All can serve as targets for treatment of thyroid cancer with
MIRAGE therapy. And .sup.57Fe can be incorporated into heme
proteins and red blood cells. The latter target can be irradiated
at the frequency of deoxyhemoglobin which differs from that of
oxyhemoglobin to exploit the relative hypoxia of tumors where
hypoxia results in a greater concentration of deoxyhemoglobin.
Furthermore, damage to the red blood cells in the tumor leads to
coagulation followed by thrombosis of the blood supply to the tumor
and concomitant tumor death.
[0311] For case 2
[0312] The energies of the nuclear states are weakly influenced by
the chemical environment. The energies of these perturbations
relative to the energy of the nuclear transitions in the absence of
effects from the environment are of the order of 10.sup.-10.
However, the line width of the Mossbauer effect is extremely narrow
with monochromaticity of the order of one part in 10.sup.13. This
permits selective absorption in a spatial region containing
selected cells where these extremely small effects differ from
those of the background value of nonselected tissue.
[0313] There are three principle interactions, the chemical isomer
shift, the magnetic hyperfine interaction, and the quadrapole
hyperfine interaction.
CHEMICAL ISOMER SHIFT
[0314] The nucleus which is charged interacts with the oppositely
charged S electron density which penetrates to the nucleus. For
example, the integrated coulombic energy for an electron of charge
-e moving in the field of a point nucleus of charge +Ze is given
by: 10 E o = 2 e 2 4 o o .infin. 2 T r ( 14 )
[0315] where .epsilon.o is the permittivity of a vacuum, r is the
radial distance, and -e.psi..sup.2 is the charge density of the
electron in volume element d.epsilon.. When the nucleus undergoes a
transition, the size of the nucleus changes which results in a
change in the electric monopole or coulombic interaction between
the electronic and nuclear charges.
[0316] The energy of radiation which produces resonant absorption
is a function of the effective electron density at the absorbing
nucleus; thus, it shifts as a consequence of a change in the
nuclear S electron density. This is seen as a shift of the
absorption line away from zero velocity and is variously known as
the chemical isomer shift, or centre shift, and is designated by
the symbol.delta.. The Mossbauer experiment compares the difference
in energy between the nuclear transitions in the source and
absorber, so that the chemical isomer shift as observed is given by
11 = 1 5 o Ze 2 K 2 K K ( o ( o ) absorber 2 - o ( o ) source 2 ) (
15 )
[0317] where R is the nuclear radius, e is the charge of an
electron, and Z is the atomic number and
.vertline..psi..delta.(o).vertline..sup.2 is the non-relativistic
Schrodinger wave function at r=0. This can be related to the
measured Doppler velocity units, v, by v=(.psi.).delta.;. (16)
[0318] In equation 15, .vertline..psi..sub.5(o).vertline..sup.2 is
the s electron density at the nucleus, and not the s electron
occupation in the formal chemical sense. If .delta..sup.R.sub.R is
positive, a positive value of the chemical isomer shift, .delta.,
implies the s electron density at the nucleus in the absorber is
greater than that in the source.
.vertline..psi..sub.5(o).vertline..sup.2 includes contributions
from all the occupied s electron orbitals in the atom, but is
naturally more sensitive to changes which take place in the outer
valance shells. Although the values of
.vertline..psi..sub.5(o).vertline..sup.2 for p, d, and f electrons
are zero, these orbitals nevertheless do have a significant
indirect interaction with the nucleus via interpenetration
shielding of the s electrons. For example, a 3d.sup.54s.sup.1
configuration will have a larger value of
.vertline..psi..sub.5(o).vertli- ne..sup.2 than 3d.sup.64s.sup.1
because in the latter case the extra d electron shields the 4s
electron from the nucleus.
MAGNETIC HYPERFINE INTERACTIONS
[0319] The nucleus has a magnetic moment, p, when the spin quantum
number, I, is greater than zero. Its energy is then affected by the
presence of a magnetic field, and the interaction of .mu. with a
magnetic flux density of .beta. is formally expressed by the
Hamiltonian
H=-.mu..multidot..beta.=g.mu..sub.NI.multidot..beta. (17)
[0320] where .mu..sub.N is the nuclear magneton (eh/4
mp=5.049.times.10.sup.-27 Am.sup.2 or J/T) and g is the nuclear
g-factor [g=u/(I .mu..sub.N]. Solving for this Hamiltonian gives
the energy levels of the nucleus in the field to be 12 E m = - B I
m z = - g m B z m z ( 18 )
[0321] where m.sub.z is the magnetic quantum number and can take
the values I, I-1, . . . -I. In effect, the magnetic field splits
the energy level into 2I+1 non-degenerate equi-spaced sublevels
with a separation of .mu.B/I. For a Mossbauer nucleus, there may be
a transition from a ground state with a spin quantum number Ig and
a magnetic moment .mu.g to an excited state with spin Ie and
magnetic moment .mu.e. In a magnetic field, both states will be
split according to equations 17 and In NMR, radio frequency
transitions occur within nondegenerate levels of the ground state;
whereas, for the Mossbauer effect gamma ray transitions take place
between nondegenerate magnetic sublevels of the ground and excited
nuclear states provided that the selection rule .DELTA.m.sub.z=o,
.+-.1 is obeyed [this is called a magnetic dipole (M1) transition
which is the predominant transition]. As the result of the presence
of an internal magnetic field which can be generated by an unpaired
electron in the atomic environment that can induce an imbalance in
electron spin density at the nucleus or by an externally applied
field, the degeneracy of the ground and excited nuclear level is
lifted. The resultant Mossbauer spectrum contains a number of
resonance lines, but is nevertheless symmetrical about the
centroid. A typical example of magnetic hyperfine splitting is
illustrated in FIG. 16 which is drawn to a scale appropriate to Sn.
For this isotope I g=1/2, I.sub.e={fraction (3/2)},
.mu.g=-1.041.mu.N and .mu.e=.sup.0.67.mu..sub.N. The change in sign
of the magnetic moment results in a relative inversion of the
multiplets. The six lines are the allowed .DELTA.m.sub.z=0,.+-.1
transitions, and the resultant spectrum is indicated in the stick
diagram. The lines are not of equal intensity, but the 3:2:1: 1:2:3
ratio shown here is often found for example in the .sup.57Fe and
.sup.119Sn resonances in randomly oriented polycrystalline samples.
A more detailed account of the relative intensities is given in the
discussion of polarization of gamma rays.
OUADRAPOLE HYPERFINE INTERACTIONS
[0322] Mossbauer nuclei with nuclear states with I>1/2 have a
nuclear quadrapole moment. An electric quadrapole interaction
between the nuclear quadrapole moment and the local electric field
gradient tensor at the nucleus produces a multiline spectrum as was
the case for magnetic hyperfine splitting. The electric quadrapole
interaction in Mossbauer spectroscopy is very similar to that in
nuclear quadrapole resonance spectroscopy. The main difference is
that the latter is concerned with radio frequency transitions
within a hyperfine multiplet of a ground state nucleus, whereas,
the former is a gamma ray transition between the hyperfine
multiplets of the nucleus in its ground and excited states. The
electric field gradient is determined by the electronic occupancy
of atomic orbitals and is influenced by the bonding to other atoms.
Also, in some compounds, the Mossbauer atom has an intrinsically
high symmetry (e.g. Fe.sup.3+d.sup.5 ion has a half filled shell
and is a spherical s-state ion) but may still show a quadrapole
splitting. The latter originates from charges external to the atom,
such as other ions, which polarize the spherical core and can
induce a very large electric field gradient at the nucleus.
[0323] Selectivity in the eradication of selected cells while
sparing nonselected cells can be achieved where a change in the
isomer shift, magnetic hyperfine, or quadrapole hyperfine
interaction is realized in the selected cells which is different
from that of nonselected cells. For example, cancer cells are known
to have differences in ion concentrations and ph from normal cells.
Binding of an ion or molecule such as a proton (in the case where
the MIRAGE pharmaceutical is a weak acid or weak bse with a pKa or
pKb, respectively, which is approximately equal to the pH of the
organic media at the selected tissue site or the nonselected tissue
along the ray path of the administered gamma rays) could result in
a change in the electronic interaction at the Mossbauer nucleus and
result in a distinct spectrum. Also, the presence of a protein in
the target cell which binds to the drug to affect the spectrum
could also provide discrimination. This mechanism is discussed in
more detail under MIRAGE AIDS Drug.
[0324] For case 3
[0325] The nuclear spin moments of Mossbauer isotopes become
aligned in an imposed magnetic field. The presence of the field
lifts the degeneracy of the quantum states and the nucleus must
occupy one of these quantum states. Transitions between magnetic
sublevels of nuclear states during resonant absorption results in a
multiline spectrum. The energy of the transitions, and thus the
positions of the lines, are directly proportional to the magnetic
field strength. Therefore, by manipulating the external magnetic
field strength a transition between magnetic sublevels of the
ground and excited nuclear states can be created in the spatial
region of the selected tissue such that the energy to achieve
resonance is distinctly different from that which achieves
resonance in the surrounding nonselected tissue. This is achieved
when the resonant energy of the selected tissue is shifted by one
line width from that of nonselected tissue. The energies and the
dimensions involved are calculated for .sup.119Sn as follows: The
line width for .sup.119Sn is 2.57.times.10.sup.-8 ev, the magnetic
moment is -1.046 .mu..sub.N which resonates at 32 MHz for a 2T
field. This represents an energy of 1.32.times.10.sup.-7 ev. This
energy is directly proportional to the magnetic flux density, and a
realistic flux density gradient is 2000 guass/cm or 10% of the flux
density per cm. Since the line width is 20% of the magnetic energy,
a 20% change in the flux density is necessary to shift the resonant
energy by one line width. This relationship gives 2 cm as the
spatial displacement for which the nonselected surrounding tissue
becomes transparent with respect to the Mossbauer effect to the
radiation which is resonantly absorbed by the selected tissue.
[0326] For case 4
[0327] Selective absorption in a predetermined region of space can
be accomplished by polarizing the source gamma rays and by aligning
the spin moments of the selected absorber nuclei with an external
magnetic field in a vector orientation relative to the incident
polarized gamma ray to permit a nuclear transition between magnetic
sublevels which is quantum mechanically allowed only for the proper
spin moment alignment. Polarized gamma rays can be obtained by
three methods, magnetized ferromagnetic sources, quadrapole split
sources, or filter techniques as shown by U. Gonser and H. Fischer,
Current Topics in the Physics of Mossbauer Spectroscopy, The Exotic
Side of the Method: Resonance Gamma Ray Polarimetry, 99-135;
incorporated by reference.
[0328] Selectivity via polarization of the source and absorber
nuclei is possible due to the polarization and angular dependence
of transitions between hyperfine quantum sublevels. The intensity
of the emitted or absorbed radiation and its dependence on
orientation are determined by conservation of angular momentum in
the system of nucleus plus gamma ray (quantum selection rules)
where the quantum-mechanical treatment of electromagnetic radiation
leads to the introduction of photons which are bosons of vanishing
rest mass and quantized angular momentum. The intensity of a
particular hyperfine transition between quantized sublevels is
determined by the coupling of the two nuclear angular momentum
states. It can be expressed as the product of two terms which are
angular-dependent and angular-independent, respectively.
[0329] The former averages to unity for the case of the emission
from a source or absorption by the absorber nuclei when all
orientations of the magnetic axes of the nuclei are equally
possible. Such a case exists for a randomly oriented
polycrystalline powder sample where an internal field exists. The
intensity in this instance is given by the square of the
appropriate Clebsch-Gordan coefficient:
Intensity.zeta.<I,J-M,M/I.sub..zeta.M.sub.2>.sup.2 (19)
[0330] where the two nuclear spin states I.sub.1 and I.sub.2 have
I.sub.z values of m.sub.1 and m.sub.2 and their coupling obeys the
vector sum J=I.sub.1+I.sub.2 and m=m.sub.1-m.sub.2. J is referred
to as the multipolarity of the transition, and the intensity is
greater if J is small: if J=1, it is referred to as a dipole
transition, while with J=2 it is a quadrapole transition. Most of
the Mossbauer transitions take place without a change in parity, so
that the radiation is classified as a magnetic dipole (M1) or
electric quadrapole (E2) transition. The selection rule for an M1
or E1 transition is .DELTA.m.sub.z=0.+-.1, and for an Etransition
is .DELTA.m.sub.z1,.+-.1,.+-.2.
[0331] The most frequently used coefficients are those for the
1/2.fwdarw.{fraction (3/2)}M1 transition, and these are given in
Table I.sub.1, may be either the ground or excited state spin.
Although there are nominally eight transitions, the +{fraction
(3/2)}.fwdarw.1/2 and .sup.-{fraction (3/2)}.fwdarw..sup.+1/2
transitions, have a zero probability (forbidden). The six finite
coefficients, C.sup.2, which express the angular-independent
intensity have a total probability of unit intensity and give
directly the 3:2:1:1:2:3 intensity ratios for a magnetic hyperfine
splitting, shown in FIG. 16. The corresponding terms for a
quadrapole spectrum are obtained by summation and give a 1:1
ratio.
9TABLE 9 The Relative Probabilities for a 1/2, 3/2 Transition C
C.sup.2 .THETA.(J,m) m.sub.2 -m.sub.1 m (1) (2) (2) Magnetic
spectra (Ml) 13 + 3 2 14 + 1 2 +1 1 15 1 4 16 3 4 ( 1 + cos 2 ) 17
+ 1 2 18 + 1 2 0 19 2 3 20 1 6 21 3 2 sin 2 22 - 1 2 23 + 1 2 -1 24
1 3 25 1 12 26 3 4 ( 1 + cos 2 ) 27 - 3 2 28 + 1 2 -2 0 0 -- 29 + 3
2 30 - 1 2 +2 0 0 -- 31 + 1 2 32 - 1 2 +1 33 1 3 34 1 12 35 3 4 ( 1
+ cos 2 ) 36 - 1 2 37 - 1 2 0 38 2 3 39 1 6 40 3 2 sin 2 41 - 3 2
42 - 1 2 -1 1 43 1 4 44 3 4 ( 1 + cos 2 ) C.sup.2 .THETA.(J,m)
Transition (2) (2) Quadrupole spectra (Ml) whcn .eta. = 0 45 1 2 ,
46 1 2 47 1 2 48 1 2 + 3 4 sin 2 49 3 2 , 50 1 2 51 1 2 52 3 4 ( 1
+ cos 2 ) (1) The Clebsch-Gordan coefficient 53 ( 1 2 1 - m 1 m | 3
2 m 2 ) (2) C.sup.2 and .THETA.(J,m) are the angular-independent
and angular-dependent terms normalized to a total radiation
probility of 54 m 1 m 2 C 2 ( J , m ) = 1
[0332] The angular dependent terms, .theta.(J,M), are expressed as
the radiation probability in a direction at an angle a to the
quantization axis (i.e. the magnetic field axis or the principle
electric field axis: note that the values in the latter case are
only correct if the electric field gradient about the principle
axis is symmetric). The intensity for a polycrystalline sample is
obtained by integration over all a to obtain .theta.(J,M) as
follows: 55 3 2 sin 2 _ = 1 4 o 2 3 2 sin 2 sin = 1 ( 20 )
[0333] and the total of emitted radiation is independent of a and
normalized to unity, i.e. 56 m , m 2 1 4 < I , J - m , m / I 2 m
2 > 2 ( J , M _ ) = 1 ( 21 )
[0334] Coefficients such as those in Table 9 are necessary to
interpret the a ngular dependence of the spectrum from a single
crystal or oriented absorber. For example, a magnetically ordered
metal alloy or oxide absorber may often be polarized by magnetizing
in a small external magnetic field to give a unique direction of
the internal field. The expected line intensities can then be
predicted from Table 9 to be in the ratios 3:x:1:1:x:3 where x=4
sin.sup.2.theta./(1+cos.sup.2.theta.); in particular, the
.DELTA.m=o transitions have a zero intensity when observed along
the direction of the field (.theta.=0.degree.) and a maximum
intensity perpendicular to the field (.theta.=90.degree.) This is
illustrated schematically in FIG. 17.
[0335] The equivalent behavior in the quadrapole spectrum is a 1:3
ratio for the gamma ray axis parallel to the direction of the
principle electric field gradient axis and 5:3 ratio perpendicular
to the principle axis.
[0336] The angular dependence of the polarization absorption
phenomenon is demonstrated experimentally as summarized in FIG.
18a, b. The spectra in FIG. 18 were obtained with a single crystal
of .alpha.--Fe.sub.2O.sub.3 (hematite). The crystal was cut
parallel to the basal plane and measured (a) at 80.degree. K. and
(b) at room temperature. The change in the relative line
intensities indicates a reorientation of the spins (Morin
transition). Below the Morin temperature (T.sub.m=260.degree. K.),
the spins are oriented perpendicular to the basal plane of the
rhombohedral structure and are parallel and antiparallel to the
gamma ray direction. Thus, the .DELTA.m=0 lines disappear. Above
the Morin temperature the spins flip and align into the basal plane
and the .DELTA.m=0 lines become strong.
[0337] Selective eradication of a selected cell line such as cancer
tissue can be achieved by polarizing the cancer tissue with an
orientation different from surrounding normal tissue and by
irradiating with radiation which excites the corresponding
transition. For example, referring to FIG. 18, the nuclei of the
MIRAGE pharmaceutical present in the cancer tissue can be aligned
perpendicularly to the propagation direction of the gamma ray;
whereas, the Mossbauer nuclei present in normal tissue are aligned
parallel to the gamma ray propagation direction where alignment in
both cases is achieved with an external magnetic field. By
irradiation with gamma rays which are resonant with the .DELTA.m=0
transition, only the cancer tissue will absorb the radiation.
[0338] For Case 5
[0339] The line shape for either an absorption or emission
Mossbauer line is given by 57 66 ( w ) = 4 - .infin. .infin. Q _ (
t ) e - T 2 ( 4 ) j t t ( 22 )
[0340] where the correlation function
[0341] 58 Q ( t ) = < m / - k x ( f ) ik x ( o ) / m > ( 23
)
[0342] where Xo is the displacement of the nucleus from its
equilibrium position; h.multidot.k is the momentum of the gamma
ray; and the bar devotes a thermal
average;hu=E.multidot.E.sub.t,
[0343] where E.sub.t is the difference in energy between the
initial and final nuclear states, is the natural line width of the
nuclear excited state; and .vertline.m> represents the phonon
states of the absorber or source. For the case of harmonic phonon
go states, the factor {overscore (Q(+))} predicts a broad
background to the Mossbauer line due to the distribution of thermal
phonons in the source or absorber. However, if the source or
absorber is excited ultrasonically at a single frequency u.sub.o,
the behavior of Q(+), and hence the line shape is altered
drastically. The line shape of an ideal crystal of harmonic phonon
states for the two cases in which the phonon relaxation time; the
time it takes the initially monochromatic ultrasonic beam to spread
into a wave packet characterized by kT, is either very long or very
short is given respectively as follows. 59 W ( w ) = e 4 - .infin.
.infin. e - o I n ( o ) ( w - w n ) 2 + ( 4 ) 2 ( 24 )
[0344] where In is the modifified Bessel function of the first
kind; e.sup.-.zeta. is the Deby -Waller factor;
.zeta..sub.o=<(k.multidot.x.- sub.o).sup.2>
[0345] where Xo is the displacement of the nucleus from equilibrium
in the oth normal mode. 60 W ( w ) = - 4 n = - .infin. .infin. J n
2 ( 1 2 o ) ( w - nw o ) 2 + ( 4 ) 2 ( 25 )
[0346] where Jn is the unmodified Bessel function of the first
kind. For the first case, a short phonon relaxation time results in
a Boltzman distribution of ultrasonic phonon states which produces
the Mossbauer line shape of Equation 24 where the original single
line at frequency u.sub.+=E+/.sub..zeta.=0 as been partially split
up into an infinite number of side bands, each of relative
intensity e.sup..zeta.In(.zeta.) spaced at intervals of nwo,
integer multiples of the ultrasonic frequency, from the central,
unshifted line.
[0347] For the second case of a long phonon relaxation time, the
lattice phonons are in thermal equilibrium, but the ultrasonic
phonons are unable to interact with the thermal phonons; thus, an
ultrasonic mode is superimposed to produce the Mossbauer line shape
of Equation 25 where, again as for Equation 24, the spectrum splits
into an infinite number of side bands, in this case of relative
intensity .tau..sub.n (1/2.GAMMA..zeta.) spaced as for the former
case at intervals of nwo, integer multiples of the ultrasonic
frequency from the central, unshifted line.
[0348] Selective Mossbauer absorption in a predetermined region of
space can be accomplished by simultaneously administering a focused
or collinated ultrasonic beam and a gamma ray beam in such a
fashion that the beams intersect at the site of the target tissue.
The former beam excites a component of ultrasonic motion of the
Mossbauer absorber nuclei in the direction of the latter beam to
create absorption sidebands spaced at integer multiples of the
ultrasonic frequency from the central, unshifted line as described
by J. Mishory and D. I. Bolef, Mossbauer Effect Methodology, Irwin
J. Gruverman, Editor, Vol. 4, (1968) pp. 13-35, incorporated by
reference. The administered gamma rays are resonant with a sideband
of energy which is not resonant with any of the Mossbauer absorber
nuclei in the nonselected tissue along the gamma ray path; thus,
selectivity is achieved.
ENERGY SELECTIVE THERAPY
[0349] The cross-section for absorption of resonant radiation by
Mossbauer nuclei are 10.sup.8 times that of water; however,
nonspecific scattering and absorption occurs for all gamma
radiation. The predominent mechanism is the photoelectric effect
and Compton scattering.
[0350] The photoelectric and Compton cross-sections are summarized
in Table 10 which contains the mass energy absorption coefficients
in the absence of the Mossbauer effects. The equation for
determining the total dose from gamma ray treatment and the depth
of penetration of the photons appears in FIG. FIG. 12 and Table 10
demonstrate the relationship that photons of higher energy
penetrate deeper into tissue. Since the different Mossbauer sources
demonstrate a wide range of photon energies, therapies can be
designed to exploit this phenomenon to deliver the energy of the
radiation to a selected depth. Mossbauer sources of low energy
gamma rays which do not penetrate deeply can be used to deliver
therapy superficially and spare deep tissue. For example, .sup.57Co
is the source of a 14.4 KeV Mossbauer gamma ray with a mass energy
tissue absorption coefficient of 1.32 cm.sup.2/gm and would be
suitable for intraoperative radiation and endoscopic radiation
using a miniturized source and mass drive or ultrasonic drive.
Breast, bowel, and pancreatic cancer are candidates for the former;
and lung cancer is a candidate for the latter. Mossbauer sources of
high energy gamma rays which penetrate deeply can be used to treat
tumors that are not located superficially. .sup.155Gd is the source
of a 60 KeV Mossbauer gamma ray with a mass energy bone absorption
coefficient of 0.03 cm /gm and represents a suitable source for the
treatment of primary and metastatic bone cancer and deep solid
tumors.
10TABLE 10 MASS ENERGY ABSORPTION COEFFICIENTS M A K C Water AL M
0.010 6.20 77.0 89.8 1.89 4.66 19.0 4.96 MASS .015 19.1 21.6 28.9
1.32 1.20 5.80 1.36 ENERGY .020 8.31 10.5 12.5 0.523 0.6 2.31 0.511
ABSORPTION .030 2.16 3.12 3.75 0.117 0.117 0.713 0.151 COEFFICIENTS
.010 0.074 1.25 1.52 0.0617 0.000 0.305 0.0677 (u.sub.en) .050
0.181 0.626 0.761 0.0391 0.6381 0.158 0.0149 [cm.sup.2/gm] 0.060
0.281 0.367 0.413 0.0301 0.0701 0.082 0.0079 0.191 0.0293 .10 0.111
0.0272 0.0231 0.0252 .15 0.0168 0.0133 0.0188 0.0278 0.0251 0.0301
0.0276 .20 0.0302 0.0339 0.0367 0.0300 0.0268 0.0102 0.0297 .30
0.0278 0.0301 0.0119 0.0320 0.0288 0.0311 0.0317 .40 0.0271 0.0299
0.0308 0.0329 0.0116 0.0725 .50 0.0271 0.0291 0.0301 0.0330 0.0297
0.0316 0.0327 .60 0.0270 0.0291 0.0301 0.0329 0.0296 0.0315 0.0326
.80 0.0261 0.0282 0.0290 0.0321 0.0289 0.0306 0.0718 1.0 0.0252
0.0272 0.0279 0.0311 0.0280 0.0297 0.0308 1.5 0.0228 0.0217 0.0253
0.0283 0.0255 0.0270 0.0381 2.0 0.0212 0.0228 0.0231 0.0260 0.0218
0.0257 3.0 0.0193 0.0208 0.0213 0.0227 0.0205 0.0219 0.0225 4.0
0.0162 0.0199 0.0201 0.0207 0.0186 0.0199 0.0201 3.0 0.0176 0.0193
0.0200 0.0190 0.0173 0.0186 0.0188 6.0 0.0175 0.0180 0.0198 0.0180
0.0163 0.0178 0.0178 8.0 0.0172 0.0190 0.0197 0.0165 0.0130 0.0165
0.0167 9.0 0.0175 0.0191 0.0201 0.0133 0.0111 0.0159 0.0151
[0351] Modifications and substitutions of the compounds,
pharmaceuticals, apparatus, methods, systems, and process steps
made by one skilled in the art is within the scope of the present
invention. Moreover, although Mossbauer absorption includes the
absorption of gamma rays, the scope of the present invention
includes in the term Mossbauer absorption the absorption of
electromagnetic energy at narrow absorption lines or regions by
selected materials. Furthermore, the terms wavelength, energy and
frequency used herein according to the to present invention provide
characteristics related according to the formula
E=hv=hc/.lambda.
[0352] Thus the scope of the present invention is not limited
except according to the claims which follow.
* * * * *