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Biomedical subjects

A Mohamed

Publications and source records attributed to A Mohamed.

83 records · Page 5Linked to original sources
PubMed1983

Characterization of histamine receptors in cat cerebral arteries in vitro and in situ.

Histamine is probably a mediator of vascular responses in the brain, but there is little experimental evidence for its importance in this role. By using both in vitro and in situ techniques, we have studied responses of cat pial arteries to stimulation of histamine receptors by pharmacological agents. In vitro, histamine and 2,2-pyridylethylamine (PEA, H1 agonist) caused contraction of resting arteries while impromidine (H2 agonist) was without effect. The PEA-induced constriction was blocked by the histamine H1 antagonist, mepyramine. When the arteries were precontracted (by 3 X 10(-6) M prostaglandin F2 alpha), however, all three agents caused vascular relaxation with an order of effectiveness as follows: histamine = impromidine much much greater than PEA. The responses of histamine and impromidine were reduced by the H2-antagonists, metiamide or cimetidine. Schild plots for the H2 receptor antagonists resulted in pA2 values of 6.90 and 7.03 for metiamide and cimetidine, respectively. In situ, neither agonist caused pial arterial constriction. Impromidine was considerably more effective than PEA in producing arterial dilatation. Metiamide reduced the effect of impromidine, whereas the dilatation of PEA was reduced by mepyramine. Dilatations resulting from PEA persisted in the presence of metiamide. Our results are consistent with the hypothesis that histamine H2 receptors are present in cerebral vascular smooth muscle as identified both in vitro and in situ. Indications for the additional presence of H1 receptors are, however, weak.

Animals↗
PubMedDate not supplied

Needle track seeding following percutaneous ethanol injection for treatment of hepatocellular carcinoma.

We report two cases of needle track seeding in the subcutaneous tissue and intercostal muscles following percutaneous ethanol injection for the treatment of hepatocellular carcinoma. In one patient, tumor seeding was observed 11 months after a total of 12 alcohol injections, and in the other patient, tumor seeding was observed 30 months after a total of 18 alcohol injections. The cases reported in the literature are discussed.

Administration, Cutaneous↗
PubMedDate not supplied

Impact of hepatitis C virus infection on schistosomal liver disease.

BACKGROUND/AIMS: This study was conducted to determine whether Hepatitis C virus infection has a role in patients with schistosomal liver disease. METHODOLOGY: Sixty patients with hepatosplenic schistosomiasis and evidence of portal hypertension were seen at the Armed Forces Hospital Riyadh, Saudi Arabia over 5 years. The impact of Hepatitis C virus infection on chronic schistosomal liver disease was studied in 30 of these patients (group one) who were Hepatitis C virus positive and compared with the other 30 patients (group two) who were Hepatitis C virus negative (control group). RESULTS: Hepatitis C virus may be an important factor contributing to deterioration of liver function for patients with hepatosplenic schistosomiasis. Liver functions showed elevated ALT in 83.3% in group one compared to 23.4% in group two. Liver biopsy in 19 patients (group one) and 16 patients (group two) showed evidence of schistosomiasis and in patients of group one, liver biopsy also showed chronic active hepatitis together with Schistosoma in 57.9%, and cirrhosis in 31.6%. None of group two patients had cirrhosis. Alpha-fetoprotein levels were elevated in 16 patients (group one) and 3 of these patients had hepatocellular carcinoma. None of the control group had radiological or histological evidence of hepatocellular carcinoma. CONCLUSION: The mean age of HCV positive patients was less than the HCV negative patients, which may indicate that Hepatitis C virus infection leads to decompensation of liver function earlier in patients with Schistosoma and severe liver disease may be promoted at a younger age in Schistosoma patients with hepatitis C.

Adult↗