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H M Sharma

Publications and source records attributed to H M Sharma.

85 records · Page 5Linked to original sources
PubMed1973

Platelets in hyperacute rejection of heterotopic cardiac allografts in presensitized dogs. An experimental study.

Experiments were carried out to determine whether platelet aggregation plays a primary role in cardiac allograft hyperacute rejection, as has been observed in renal allograft hyperacute rejection. Dogs were presensitized by multiple skin grafts before a cervical heterotopic cardiac allograft was placed. One group of dogs was treated with sulfinpyrazone, a platelet inhibitor, and another was not. In the majority of the untreated dogs, the cardiac transplants were rejected hyperacutely and showed, morphologically, platelet aggregation followed by vascular disruption. In the treated dogs, hyperacute rejection was prevented, but the cardiac transplants were later rejected by primary cellular rejection. These data and the results from the experiments of other researchers lead us to propose that platelets are the "effector" of hyperacute rejection.

Animals↗
PubMed1972

Platelets in early hyperacute allograft rejection in kidneys and their modification by sulfinpyrazone (Anturan) therapy. An experimental study.

Experiments were carried out on mongrel dogs to study the early ultrastructural changes in hyperacute rejection of kidney. Renal allografts were performed on dogs presensitized by three to five skin grafts. The animals were grouped in pairs, control and treated with sulfinpyrazone, a platelet inhibitor. The electron microscopic studies showed that the earliest change in the kidney was aggregation of platelets mainly in the peritubular capillaries and a few glomeruli. Later, platelets showed degranulation with vascular damage leading to rejection of kidney. Treated dogs showed less tendency for platelets to aggregate, and graft survival was prolonged. The role or platelets in the hyperacute rejection is discussed.

Animals↗
PubMed1971

Histochemistry of lactic dehydrogenase in heart and pectoralis muscles of rat.

Left-ventricular heart muscle and pectoralis major muscle of the rat were studied to determine the intracellular localization of lactic dehydrogenase (LDH) isoenzymes. Fixation of tissue for 2 hr in 2% buffered formaldehyde provided the best preservation of the ultrastructure and enzyme activity. Total LDH activity was found diffusely in the ground substance of the sarcoplasm and in the mitochondria of the heart muscle. In skeletal muscle a strong reaction was noted in the sarcoplasmic reticulum, and moderate activity was seen in the ground substance of the sarcoplasm and in the mitochondria. Differentiation of the isoenzymes of LDH was accomplished by addition of 4 M urea or application of heat. Heart-type isoenzymes were mainly localized in the mitochondria and sarcoplasm, whereas muscle-type isoenzymes were localized mainly in the sarcoplasmic reticulum of the skeletal muscle. It is speculated that the sarcoplasmic reticulum of the skeletal muscle is the site of anaerobic glycolysis and that the sarcoplasm and mitochondria are involved primarily in aerobic metabolism of pyruvate.

Animals↗
PubMedDate not supplied

Angio-proliferative lesions in a homosexual boar with features resembling Kaposi's sarcoma.

Clinical, biopsy and necropsy studies of a homosexual boar revealed angio-proliferative lesions in the skin of the thigh, scrotum and the inguinal lymph node. Angiofibromas were identified in the dermis and subcutis of the thorax and mandible. The avidin-biotin-peroxidase complex technique demonstrated Factor VIII-related antigen as a marker for the neoplastic endothelial cells of the tumors. This boar also showed weight loss and lymphopenia. Explants of tumors were maintained in cultures for 22 passages and cultured cells produced tumors when injected subcutaneously into nude mice. No viral antigen was detected in the cultured tumor cells. Similarities and differences between the lesions in the boar and human Kaposi's sarcoma are discussed.

Animals↗
PubMedDate not supplied

Lower lipid peroxide levels in practitioners of the Transcendental Meditation program.

OBJECTIVE: Oxidative stress or free radical activity may contribute to the pathophysiology of atherosclerosis and other chronic diseases associated with aging. Because psychosocial stress has been shown to increase oxidative stress, we conducted an exploratory study to investigate the effects of stress reduction with the Transcendental Meditation program on serum lipid peroxide levels in elderly subjects. METHOD: Forty-one normally healthy subjects (aged 56 to 74 years, average 67 years) were recruited from the same Midwest city. Eighteen were long-term practitioners of the TM program (average 16.5 years). Twenty-three controls were not practicing a formal stress management technique. Venous blood samples were analyzed for lipid peroxides by the TBARS assay. A dietary questionnaire was used to assess fat intake, red meat consumption, antioxidant vitamin supplementation, and smoking. Differences between groups and subgroups were analyzed by t test, and correlations. RESULTS: Significantly lower serum levels of lipid peroxides were found in the TM practitioners compared with controls (-15%, p = .026). No significant differences were found between groups on smoking, fat intake, or vitamin supplementation. TM practitioners also had lower red meat consumption but matched subgroup analysis and partial correlations did not confirm a relationship between red meat intake and lipid peroxide levels. CONCLUSIONS: These preliminary findings suggest that lower serum lipid peroxide levels may be associated with stress reduction using the Transcendental Meditation technique. Prospective controlled trials are needed to confirm that this effect is because of TM practice rather than other lifestyle factors, such as diet.

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