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H J Glenn

Publications and source records attributed to H J Glenn.

13 recordsLinked to original sources
PubMed1977

Detection of metastatic adrenal carcinoma using 131I-6-beta-iodomethyl-19-norcholesterol total body scans.

Adrenal and total body scintigraphs with 131I-6-beta-iodomethyl-19-norcholesterol were obtained in 5 patients who had had prior resection of adrenal cortical carcinoma. The results were compared with roentgenographic findings and liver, bone, and total body gallium-67 citrate scintigraphs. Metastatic lesions were detected with radiolabeled cholesterol in 4 of 5 patients, including 3 liver metastases, 2 bone metastases, and 1 lung metastasis. These lesions were also demonstrated by one or more of the other diagnostic modalities. All initial findings were negative in a fifth patient, who developed brain metastases within two months. The 6-methyl-analog of iodocholesterol makes it possible to detect metastatic adrenocortical carcinoma with total body scans. Whether or not this agent is "tumor specific" and will be of significant clinical utility will have to be determined more fully in a larger series of patients.

Adrenal Cortex Neoplasms↗
PubMed1977

Technetium-99m stannous citrate brain-tumor uptake in mice: concise communication.

The pharmacodynamics of technetium-99m stannous citrate were studies in Yale-Swiss mice bearing a sarcoma-like transplantable brain tumor, and the renal kinetics were determined in normal mice. Using a rating system based on tumor uptake and tumor-to-brain, tumor-to-blood, and tumor-to-skin ratios, the data obtained with this compound were compared with similar data obtained previously in the same model with Tc-99m Fe-(ascorbic acid), Tc-99m Fe-(ascorbic acid)-DTPA, Tc-99m Sn-DTPA, [99mTc] pertechnetate, and [99mTc] pertechnetate with perchlorate predose. Technetium-99m stannous citrate does not appear to achieve tumor localization by a mode different from these other Tc-99m-labeled compounds, nor does it show any potential advantage as a scanning agent in the tumor model.

Animals↗
PubMed1977

Radiation damage to mouse testis cells from [99mTc] pertechnetate.

The radiation dose and the biologic damage to mouse testis from intravenously administered [99mTc] pertechnetate were studied. The dose was measured for penetrating radiations from Tc-99m, using calibrated thermoluminescent dosimeters and calculations from the uptake of the nuclide in the testis, and was found to be 4.9 rada per mCi of Tc-99. The biologic damage was measured by the decrease in the number of sperm heads in the testis, counted both by hemacytometer and by Coulter counter. In preliminary experiments using external gamma radiation from Cs-137, the number of sperm heads reached a minimum 29 days after irradiation. Twenty-nine days after injection of 5.8 mCi of Tc-99m, which gives 28 rads to the testis, the number of sperm hads decreased to 70% of control. The biologic effect corresponds to that seen after 40 rads of gamma radiation from Cs-137. The damage to mouse testis cells from internally administered Tc-99m as measured in an in vivo system appears to be at least as significant as that from external gamma irradiation, if not more so.

Animals↗
PubMed1976

Experimental models for evaluation of radioactive tumor-localizing agents.

Although subject to limitations, there is a need for carefully controlled laboratory studies using animal tumor models in research on tumor-localizing agents. This paper reviews the literature relating to the more important transplantable tumor systems, spontaneous or induced, as to origin, host, site, and radioactive agent used. The historical background of animal tumor models is discussed, including such technical aspects as source of tumor, techniques of transplantation, transplantation sites, and maintenance of transplants. Also, considered are the use of animal tumor models as predictive systems, expression of experimental results of quantitative studies of tissue uptake and comparative radionuclide tumor and distributional studies, and suggestions for future studies, such as the need of more intensive study of existing tumor models for a better understanding of the relationship between animal and human tumors, the need for the development of new tumor model systems, and for standardization of experimental protocols and procedures. A total of 48 t,mor models (26 in mice, 11 in rats, 7 in hamsters, 2 in rabbits, and 2 in dogs) are presented in seven tables dividing the models into tumors of epithelial tissue, connective tissue, hematopoietic tissues, melanin-forming tissue, neural tissues, undetermined site of origin or undifferentiated histologic pattern, and miscellaneous background. The use of animal tumor models in cancer research, which utilizes radionuclides, permits the investigator to do many things not permissible with human beings, but the extrapolation of animal results to human beings must be approached with caution, Although malignant disease, whether in animals or man, must be individualized, certain trends in animal studies can be observed. It is the goal of the laboratory investigator to be able to indicate to the clinician those trends or phenomena that, when repeatedly observed in animal model systems, may be applicable to an understanding of malignant disease in man.

Animals↗
PubMed1975

Some aspects of the radiopharmaceutics of 99m-Tc-phytate.

This paper outlines the method of preparation of 99m-Tc-phytate and its use for scanning the reticuloendothelial system. The tissue distribution studies in mice and rats indicate that 99m-Tc-phytate is a safe and effective liver imaging agent. This was confirmed by preliminary studies in human subjects. The stability of the aqueous tin-phytate complex is remarkably good, and it could be successfully used for more than two months to prepare the labelled product.

Animals↗
PubMed1975

Brain tumor-scanning agents compared in an animal model.

Sixteen radiopharmaceuticals for brain tumor localization have been compared in a mouse brain tumor model. A rating system is presented for such intercomparison. The rusults indicate that 111-in-chloride injected at pH 1.5 has the most favorable biologic characterisTICS FOR BRAIN TUMOR IMAGING.

Animals↗
PubMed1975

Kinetics of 111In-bleomycin and 111 In-chlorides in mice.

Indium-111 as the chloride and chelated to bleomycin has been reported useful as a tumor-scanning agent. This report of the kinetics of these compounds compared in Yale-Swiss mice bearing a transplantable, in situ brain sarcoma. Indium-111-chloride, pH 1.5, gave a maximum tumor uptake of 18.5% dose per gram tumor, a maximum tumor-to-brain ratio of 17.0, and a maximum tumor-to-blood ratio of 4.4. Its renal blood clearance was a slow 0.0022 ml/min. Indium-111-bleomycin showed a maximum tumor uptake of 3.0% dose per gram tumor, a maximum tumor-to-brain ratio of 13.5, a maximum tumor-to-blood ratio of 6.8, and renal blood clearance of 0.254 ml/min. The labeling of bleomycin with 111In results in a tracer with localizing properties in this tumor model which are quite different from those obtained with 111In as chloride or that labeled to bleomycin would appear to have significant potential as agents for imaging tumors.

Animals↗