Biomedical subjects
C Parsa
Publications and source records attributed to C Parsa.
Naloxone alteration of blood flow in a nonischemic region of the partially ischemic gerbil brain.
The effect of naloxone (NAL) treatment on cerebral blood flow in the partially ischemic gerbil brain was investigated. Under pentobarbital anesthesia, the right carotid artery in female gerbils was cannulated. A permanent ischemia was produced in the right anterior brain portion by carotid ligation. One hour after the surgical procedure, radioactive 51Cr, microspheres were injected via the carotid catheter before intraperitoneal administration of NAL (50 mg/kg) in saline solution. Five minutes later, radioactive 46Sc microspheres were injected via the carotid catheter. Controls were injected in the same manner with vehicle and microspheres. Brain quarters were assessed for 51Cr and 46Sc radioactivity with a gamma counter. A significant decrease in microsphere deposition was observed with NAL treatment in the right rear, nonischemic part of the brain. No changes in radioactivity were detected in the ischemic portion. These findings suggest that NAL may alter brain blood flow independently of ischemia.
Morphologic response of rat Leydig cells to hemicastration.
Hemiorchidectomized rats were followed up to 15 days postsurgery for morphologic evaluation of compensatory testicular response and its correlation to serum testosterone levels. Although gross compensatory testicular hypertrophy (CTH) was not noted, an enlarged interstitium was observed with hypertrophy and hyperplasia of Leydig cells with morphologic changes suggestive of increased cellular activity. These histologic changes were accompanied by compensatory testicular hypersecretion (CTHS) illustrated by the return of the serum testosterone levels to near the intact-control value in the later groups. Ultrastructural studies of the Leydig cells indicated an increase in the amount of smooth endoplasmic reticulum as an underlying mechanism for this response. In view of the previously reported normal serum luteinizing hormone levels after hemicastration, the compensatory hyperactivity/hypersecretion should be considered primarily an intrinsic Leydig cell response, not related to changes in the hypothalamo-hypophyseal axis.
Superficial spreading malignant melanoma with neurosarcomatous metastasis.
A case of neurosarcomatous nodal metastasis of superficial spreading malignant melanoma, without primary site desmoplasia or sarcomatous changes, is reported. Of particular interest regarding the metastasis are: the ultrastructural demonstration of numerous cytoplasmic microtubules, absence of premelanosomes, intense immunohistochemical reaction with S-100 protein antibody, and the presence, at the light microscopic level, of extranodal fibrosis. The primary lesion shows a pre-existing benign nevus and features suggestive of lamellar fibroplasia. The origin and histogenesis of melanocytic desmoplasia, in the context of a neural crest progenitor cell, and of lamellar fibroplasia, are discussed.
Cronkhite-Canada syndrome associated with systemic vasculitis: an autopsy study.
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Adenocarcinoma associated with Barrett's esophagus.
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A case report of four primary cancers: larynx, breast, kidney, and uterus.
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