No abstract available.

Intraperitoneal adminstration of radioisotopes is suggested to treat the metastatic ovarian cancer in the pertioneal cavity. Administering beta-emitting radioisotopes into the pertioneal cavity allows the maximum energy delivery to the cancerous cells of the pertioneal wall surface while sparing the normal cells located in deep site of the peritoneal wall. In this study, dose estimates of the peritoneal wall are provided to be used for prescribing the amount of 166Ho-chitosan complex administered. The 166Ho-chitosan complex diffused in the peritoneal fluid may attach to the peritoneal wall surface. The attachment fraction of 166Ho-chitosan complex to the peritoneal wall surface is obtained by simulating the ascites with Fischer rats. Both volume source in the peritoneal fluid and the surface source over the peritoneal wall surface are counted for the contribution to the peritoneal wall dose. The Monte Carlo code EGS4 is used to simulate the energy transfer of the beta particles emitted from 166Ho. A plane geometrical model of semi-infinite volume describes the peritoneal cavity and peritoneal wall. A semi-infinite plane of 10 micrometer in thickness at every 1 mm of depth in the peritoneal wall is taken as the target in dose estimation. Greater han 98 percents of attachment fraction has been observed from the experiments with Fischer rats. Given 1.3 microcurie/cm2 and 2.4 microcurie/ml of uniform activity density, absorbed dose is 123 Gy, 8.59 Gy, 3.00 Gy, 1.03 Gy, and 327 Gy at 0 mm, 1 mm, 2 mm, 3 mm, and 4 mm in depth to the peritoneal wall, respectively.
Ascites ; Ascitic Fluid ; Beta Particles ; Energy Transfer ; Ovarian Neoplasms ; Peritoneal Cavity ; Radioisotopes ; Rats, Inbred F344

No abstract available.
Humans* ; Neutrons*

188Re (beta=22 MeV; gamma=155 keV; T1/2=16.9 hours) is an attractive therapeutic radioisotope which is produced from decay of reactor-produced tungsten-188 parent (T1/2=69 days). 188W has been produced from the double neutron capture reaction of 186W. 188Re can be easily obtained by elution of saline on alumina based 186W/188Re generator, which is commercially available. Complexes labelled with 188Re have been developed for the radiotherapy treatment of diseases because of the desirable nuclear properties of the radioisotope and it's chemical properties similar to those of technetium, a well established diagnostic agent.
Aluminum Oxide ; Humans ; Neutrons ; Parents ; Radiotherapy ; Technetium

Korea has advanced nuclear and radioisotope industry, and it is urgent to establish a national system to countermeasure the radiation accidents and preparedness for radiation emergency medical management. The Government opened the National Radiation Emergency Medical Center (NREMC) in the Korea Institute of Radiological and Medical Sciences (KIRAMS) in 2002, and the NREMC is setting up a radiation emergency medical preparedness and assistance network in nationwide. On April 30, 2003 the special law was proposed for the physical protection of nuclear facilities and emergency response against radiological accidents, which includes medical preparedness and management. Detailed guidelines for this law is being prepared by the Ministry of Science and Technology (MOST), and will be take effect in February 2004. Per this guideline, regional emergency medical centers will be appointed by the MOST, and the NREMC will operate this national system including education of the medical personnel.
Education ; Emergencies* ; Jurisprudence ; Korea ; Medical Assistance* ; Radioactive Hazard Release

No abstract available.
Genetic Therapy*

No abstract available.
Immunoglobulin G* ; Pentetic Acid* ; Polymers*

To assess the correlation between the remaining serum testosterone and bone mineral density(BMD), and to determine the effect of exogenous testosterone on BMD in subjects with male hypogonadism, we evaluated the serum testosterone levels and BMDs of the femur neck, Ward's triangle and the spine(L1-4) in 20 subjects with Klinefelter's syndrome and 7 with hypogonadotropic hypogonadism before and after testosterone replacement. BMDs of the femur neck, Ward's triangle and the spine were below the age-matched normal mean at 77.8%(21/20), 74.1%(20/27) and 88.9%(24/27), respectively. There were significant differences in serum testosterone levels and the spinal BMD between the two groups and the BMD of the spine closely correlated with the serum testosterone level (R = 0.63, p < 0.001). Following a mean 11.8 +/- 4.9 months of testosterone replacement, the BMD at all sites increased significantly and the pretreatment difference in spinal BMD between the two groups disappeared. We conclude that, although testosterone may increases the bone density, it has a site-specific effect of maintaining and increasing the bone mass especially at the spine in male hypogonadism.
Adult ; Bone Density/*drug effects/physiology ; Human ; Hypogonadism/blood/*metabolism ; Klinefelter Syndrome/blood/drug therapy/*metabolism ; Male ; Middle Age ; Testosterone/blood/metabolism/*pharmacology

No abstract available.
Brain Neoplasms* ; Brain* ; Tomography, Emission-Computed, Single-Photon*

PURPOSE: The pvrpose of this study was to evaluate the accuracy of radioactivity quantitation in Tc-99m SPECT by using combined scatter and attenuation correction. MATERIALS AND METHODS: A cylindrical phantom which simulates tumors (T) and normal tissue (B) was filled with varying activity ratios of Tc-99m. We acquired emission scans of the phantom using a three-headed SPECT system (Trionix, Inc.) witb two energy windows (photopeak window: 126 154 keV and scatter window: 101 123 keV). We performed the scatter correction with dual-energy window subtraction method (k=0.4) and Chang attenuation correction. Three sets of SPECT images were reconstructed using combined scatter and attenuation correction (SC+AC', attenuation correction (AC) and without any correction (NONE). We compared T/B ratio, irnage contrast [(T-B)/(T+B)) and absolute radioactivity with true values. RESULTS: SC+AC images had the highest mean values of T/B ratios. Image contrast was 0.92 in SC+AC, which was close to the true value of 1, and higher than AC (0.77) or NONE (0.80). Errors of true activity by SPECT images ranged from 1 to 11% for SC+AC, 22-47% for AC, and 2 16% for NONE in a phantom which was located 2.4cm from the phantom surface. In a phantom located 10,0cm from the surface, SC+AC underestimated by ?4%, NON.E 40%. However, AC overestimated by 10%. CONCLUSION: We conclude that accurate SPECT activity quantitation of Tc-99m distribution can be achieved by dual window scatter correc.tion combined with attenuation correction.
Radioactivity ; Tomography, Emission-Computed, Single-Photon*