Biomedical subjects

S A Suleiman

Publications and source records attributed to S A Suleiman.

21 records · Page 2Linked to original sources

PubMedDate not supplied

Effect of acute ethanol consumption on hepatic lysosomal enzymes and calcium concentration during rat liver regeneration.

Effect of alcohol consumption on the activity of two lysosomal nucleases, deoxyribonuclease II (DNAase II) and ribonuclease II (RNAase II) and calcium concentration have been studied during liver regeneration of Sprague-Dawley rats over a period of 10 days following 70% partial hepatectomy. Liver weight was completely restored in partially hepatectomized rats at 8 days in both sexes, but ethanol treatment resulted in only a partial restoration of liver weight at 10 days. Specific activity of DNAase II in partial hepatectomized animals increased by 50-75% at 6-12 hrs above sham operated controls, and the specific activity of RNAase II increased 2.3 fold at 6 hr, while calcium concentration decreased by 50% at 6-12 hrs. Ethanol treatment masked and/or delayed the increase in the specific activity of both enzymes at early stages of liver regeneration and also masked the decrease in calcium concentration. These results indicate that ethanol consumption delays the process of liver regeneration by altering the activity of lysosomal nucleases and calcium concentration.

Alcohol Drinking↗

PubMedDate not supplied

Bipyridylium herbicide toxicity: effects of paraquat and diquat on isolated rat hepatocytes.

Paraquat (1,1'-dimethyl-4,4'-bipyridylium) and diquat (1,1'-ethylene-2,2'-bipyridylium) are the two most widely used bipyridylium herbicides today. Both compounds, however, have also been found to cause liver damage in animals and man. In this study, isolated rat hepatocytes were used to assess the cytotoxicity of these two compounds. Five indices of cell damage were used to quantitate cytotoxicity: dye (trypan blue) uptake, loss of cell respiration, the extracellular release of lysosomal enzymes, the formation of thiobarbiturate (TBA)-reacting substances, and the oxidation of cellular NADH and NADPH. Diquat was shown to be more toxic than paraquat toward these cells in the first three assay systems. The acute LC50 for diquat was determined to be 80 mM, whereas the acute LC50 for paraquat was estimated to be greater than 1 M. This difference in cell sensitivity could be explained, at least in part, by the observed differences in herbicide uptake rates for these two compounds. Diquat uptake was calculated to be 9.0 +/- 1.1 nmoles/hour/10(6) cells, whereas paraquat uptake was only 5.5 +/- 0.5 nmoles/hour/10(6) cells. The dose-response curves for enzyme release and loss of cell respiration superimposed the lethality curves for both compounds. An oxidative mechanism of cytotoxicity was suggested for diquat by: the establishment of both a concentration-dependent and a time-dependent increase in lipid peroxidation (formation of TBA-reacting substances); complete oxidation of both NADPH and NADH at herbicide levels less than the LC50; and the finding that diquat stimulated glucose oxidation at subtoxic doses.

Animals↗

PubMedDate not supplied

Lipid peroxidation and human sperm motility: protective role of vitamin E.

Asthenospermia is the main factor of male infertility among patients consulting the Asir Infertility Center in Abha, Saudi Arabia. Lipid peroxidation occurring in both the seminal plasma and spermatozoa was estimated by malondialdehyde (MDA) concentration. Spermatozoal MDA concentration was higher in men with decreased sperm motility. The MDA concentration in the seminal plasma exhibited no relationship with sperm concentration, sperm motility, the number of immotile spermatozoa, or even the absence of spermatozoa. The MDA concentration in sperm pellet suspensions of asthenospermic and oligoasthenospermic patients was almost twice that of the normospermic males. The MDA concentration in the sperm pellet suspension from normospermic or oligospermic patients was about 10% that in the seminal plasma. However, the MDA concentration in the sperm pellet suspension of asthenospermic or oligoasthenospermic patients was about 15% that in the seminal plasma. Treatment of asthenospermic patients with oral Vitamin E significantly decreased the MDA concentration in spermatozoa and improved sperm motility. Eleven out of the 52 treated patients (21%) impregnated their spouses; nine of the spouses successfully ended with normal term deliveries, whereas the other two aborted in the first trimester. No pregnancies were reported in the spouses of the placebo-treated patients.

Adult↗