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D R Christman

Publications and source records attributed to D R Christman.

30 records · Page 2Linked to original sources
PubMed1977

Metal isotopes used as radioactive indicators of ocular melanoma.

We studied radioactive metal compounds to determine their localization in malignant Greene melanoma in the eye of the Syrian golden hamsters. Scintigraphy of an ocular melanoma was achieved with several radioactive metals: radioactive indium(111In)-bleomycin, radioactive gallium (67Ga)-citrate, and radioactive lead (203Pb)-tris. The 111In-bleomycin had the highest tumor uptake (5.45% dose/g), but not the highest tumor-to-background ratios. The 67Ga-citrate had a maximum tumor uptake of 4.87% dose/g at 48 hours. The 111In-chloride had a melanoma uptake of 2.26% dose/g, while with 203Pbtris the uptake was 1.61% dose/g. These uptake ratios compare favorably with that of radioactive phosphorus (32P)-2.21% dose/g. Noninvasive localization of malignant melanoma in the eye was accomplished with metal isotopes. Detailed analysis of in vitro uptake date by tumor and background tissues revealed the optimum time for scanning and precluded unnecessary trials.

Animals↗
PubMed1977

Radiopharmaceuticals XXVII. 18F-labeled 2-deoxy-2-fluoro-d-glucose as a radiopharmaceutical for measuring regional myocardial glucose metabolism in vivo: tissue distribution and imaging studies in animals.

18F-2-Deoxy-2-fluoro-D-glucose (18FDG) is rapidly extracted by the mouse heart, and the radioactivity in heart (3-4% per organ) remains relatively constant for 2 hr post injection. The brain uptake (2-3% per organ) remained relatively constant throughout the time course of the study. Liver, lungs, kidneys, small intestine, and blood all showed a rapid clearance of radioactivity after injection of 18FDG. At 120 min the heart-to-lung ratio was 12 and heart-to-liver ratio was 32. Urinary excretion of activity was approximately 16% of the injected dose at 60 min. The uptake of radioactivity by dog heart following the intravenous administration of 18FDG was 2.8-4.1% at 60 min and 2.4% at 135 min; it was regionally distributed, the areas of highest activity being the left ventricle and the interventricular septum. The brain activity was 2.1-3.5% at 120 min, with a ratio of gray matter-to-white matter of 2-3:1. Urinary excretion in dogs was 16% and 50% of the injected dose at 60 and 135 min. The chemical form of the activity in the urine, although unidentified, was not 18F-. Cross-sectional images of the myocardium of the dog after intravenous injection of 18FDG were obtained using emission tomography.

Animals↗
PubMedDate not supplied

Regional correlation of PET and CT in senile dementia of the Alzheimer type.

Alzheimer disease is manifested by both widespread and regionally restricted brain changes, some of which have recently been identified in vivo with computed tomography (CT) and positron emission tomography (PET). This is a report of the regional correlation of CT and PET measurements in 19 carefully diagnosed subjects comprising 11 controls and eight patients with senile dementia of the Alzheimer type. Regional CT attenuation values did not discriminate between the two groups, but PET using 18F-2-deoxy-2-fluoro-D-glucose demonstrated significant regional reductions (range, 21%-28%) in glucose utilization in the Alzheimer group. PET measures were also more consistently related to cognitive decline. The correlation between CT structural measures and PET metabolic measures demonstrated consistent relations between widespread PET regions and CT changes in the thalamus, posterior limb of the internal capsule, and temporal lobes. However, CT changes in the frontal white matter, caudate nucleus, and anterior limb of the internal capsule were not related to any regional PET changes. These data support previous findings of temporal lobe involvement in Alzheimer disease and suggest the involvement of structures in the region of the third ventricle.

Aged↗
PubMedDate not supplied

Positron emission tomographic studies of aging and Alzheimer disease.

In this study the positron emission tomographic (PET)-18F-2-deoxy-2-fluoro-D-glucose (FDG) technique was used to study both normal aging and senile dementia. The results derived from 15 young normal subjects (mean age, 26 +/- 5 years) and 22 elderly normal subjects (mean age, 66 +/- 7 years) failed to indicate significant metabolic changes associated with age. A group of 24 patients with senile dementia (mean age, 73 +/- 7 years) showed consistent diminutions in regional glucose use relative to the elderly normals. Across all brain regions the diminutions were 17%-24%. There were also significant correlations between the measures of glucose use and the measures of cognitive functioning. Discriminant function classification analysis results indicate that better than 80% classification accuracy can be achieved for individual PET measures. These data suggest a possible future diagnostic use of PET in senile dementia.

Adult↗