The relationship between serum cholesterol and fecal 7alpha-dehydroxylase activity in three ethnic groups in South Africa.

The ability of fecal bacteria to 7alpha-dehydroxylate primary bile acids was measured in vitro by incubating stool homogenates with labeled primary bile acids, and was compared to serum cholesterol levels in 4 South African groups: Rural Bantu (50 subjects), Urban White (20), Urban Bantu (17) and Urban Coloured (16). Mean serum cholesterol levels were 137 +/- 23, 213 +/- 51, 199 +/- 62 and 206 +/- 46 mg/100 ml, respectively. (Rural Bantu significantly different.

Fibroblast DNA synthesis activation in sponge induced granulation tissue. The effect of antineutrophil serum and cyclophosphamide.

DNA synthesis in rat and rabbit polyvinyl sponge induced granulation tissue has been studied using thymidine (methyl-3H). Synthesis was determined by measurement of thymidine incorporation into cold trichloroacetic acid insoluble material and by autoradiography. Granulation tissue was removed and immediately incubated in vitro in the presence of thymidine (methyl-3H) for three hours.

The mechanism of action of a single dose of methylprednisolone on acute inflammation in vivo.

A model system for the study of inflammation in vivo has been developed using the 16-h polyvinyl sponge implant in the rat. This system allows for simultaneous measurement of in vivo chemotaxis, volume of fluid influx, and fluid concentrations of lysosomal and lactic dehydrogenase (LDH) enzymes. In addition, the enzyme content of inflammatory fluid neutrophils may also be determined.

Kinetic study of neutrophil and inflammatory fluid beta glucuronidase.

Beta glucuronidase obtained from rat inflammatory fluid and granulocytes was studied kinetically. Linear increases in activity occurred with time and enzyme concentration. No evidence of enzyme degradation during incubation was obtained.

The need for modification of the polyvinyl sponge model of connective tissue growth. Histoligic and biochemical studies in the rabbit.

Quantitative histopathologic and biochemical comparisons were made between polyvinyl sponge capsular and sponge tissue in the rabbit on different days after subcutaneous implantation. Up to 9 days the predominant cell type in the capsular tissue is the fibroblast and in the sponge it is the neutrophil. During this time period the sponge tissue shows lower rates of (14C) proline and (14C) cytidine incorporation and lower rates of total (14C) collagen synthesis than the surrounding capsule.

Nonimmune chemotaxis in vivo: inhibition by complement depletion with cobra factor.

Wistar rats were depleted of complement components using purified cobra venom factor (CoF) administered over a 30-hour period by intraperitoneal injection. Complement depletion was confirmed by immunodiffusion assay, hemolytic assay and inhibition of the reverse Arthus reaction. Rats depleted to below 3% of their normal serum complement level showed marked inhibition of chemotaxis into inflammatory fluid produced in polyvinyl sponges 24 hours after implantation into the dorsal subcutaneous region.

Absorption of bile acids from the large bowel in man.

The absorption of bile acids from the human large bowel was studied in eight patients. All patients had cholecystitis and cholelithiasis and had to undergo cholecystectomy. Cholic acid-(14)C was injected during surgery into the lumen of the cecum, hepatic flexure of the colon, or transverse colon in six patients, under the visual control of the surgeon.