Search PubMed⌕ Search

Biomedical subjects

T Richter

Publications and source records attributed to T Richter.

At least 91 records · Page 5Linked to original sources
PubMed1989

Investigations on the influence of copper succinate on the production of superoxide anion radicals by bovine small intestinal mucosa cells.

The effect of an experimental ischemia lasting for 45 minutes and a subsequent period of reperfusion of equal length on the activity of xanthine oxidase (XO) and microsomal NADPH-cytochrome P450 reductase (NADPH-CR) were investigated in the small intestinal mucosa of male neonatal calves of the breed German "Schwarzbunte". The activity of the NADPH-CR was determined by chemiluminescence. The activity of XO decreased during ischemia, but rose to values above the control level following reperfusion. 5 mg of Cu2(succinate)2 (CuSu) administered either intraarterially or intraluminally during reperfusion prevented the rise in XO. Formation of malondialdehyde decreased in the presence of CuSu. The NADPH-CR likewise showed subnormal activity values during ischemia, but also remained at a low level during reperfusion. The activity of this enzyme was further lowered by local intraarterial or intraluminal administration of 5 mg of CuSu and by 120 mg of CuSu administered intravenously during the reperfusion. These results are discussed with regard to the superoxide anion radical induced tissue lesions observed during reperfusion.

Animals↗
PubMed1989

[Hemorheologic findings in patients with ischemic heart disease].

The paper deals with the rheological properties of the blood of 38 male patients affected by ischaemic heart diseases (age: 40-75 years) and 19 healthy test persons of comparable age. The following haemorheological properties were measured. 1. Relative plasma viscosity 2. Erythrocyte aggregation 3. Erythrocyte deformability 4. Thrombocyte aggregation and 5. Whole blood viscosity. For the purpose of representing and assessing the results of measurement obtained a division was made into different groups according to the appearances of ischaemic heart disease (chronic ischaemic heart disease, unstable angina pectoris, acute heart infarct) and risk factors (smoking, diabetes mellitus, blood high pressure and hyperlipidaemia). The methods 1-3 proved to be especially suitable for representing gradual differences in the examined rheological parameters. The results obtained are discussed and evaluated.

Adult↗
PubMed1986

The importance of endothelial cells in the course of vascular surgical interventions.

Aorto-coronary bypass made by implanting the patient's own saphenous vein may exhibit a tendency to early and late occlusion. This phenomenon is influenced by a number of factors including intraoperative damages of the graft. To determine preferable techniques for preserving vein integrity, various human graft preparation techniques were compared. Endothelial damage may occur during the preparation of the saphenous vein; the extent of damage depends on the preparation technique. In our studies the endothelium was best preserved by Rheomacrodex filling at 100 water cm pressure. Early occlusion seems to be best avoided in certain conditions using Gore-tex (polytetrafluoro-ethylene) prostheses due to the fact that the structure of Gore-tex simulates the normal endothelium covering of the luminal surface of the vessels and renders quick "re" endothelialization. This may reduce the hazard of early graft occlusion. In the present study experimental models and grafts implanted in humans were compared and results were tested by scanning electron microscopy.

Adult↗
PubMed1984

Rapid visual detection of Escherichia coli and Vibrio cholerae Heat-labile enterotoxins by nitrocellulose enzyme-linked immunosorbent assay.

A modification of the enzyme-linked immunosorbent assay for a sensitive and rapid visual detection of heat-labile enterotoxins from Escherichia coli and Vibrio cholerae is described. Small amounts of bacterial supernatant fluids are bound to nitrocellulose filters which are used as sorbents in the nitrocellulose enzyme-linked immunosorbent assay. The test is based on the immunological similarity between V. cholerae and E. coli heat-labile enterotoxins. Six isolates of V. cholerae and 48 isolates of E. coli were examined for heat-labile enterotoxins by the nitrocellulose enzyme-linked immunosorbent assay and the Vero cell bioassay. With some strains, the nitrocellulose enzyme-linked immunosorbent assay was found to be more sensitive for detection of E. coli heat-labile enterotoxin than the Vero cell test. A similar result was obtained by endpoint titration of heat-labile enterotoxin-positive E. coli H10407 culture fluid in both assays. The sensitivity of the nitrocellulose enzyme-linked immunosorbent assay for the detection of purified cholera toxin was at a total level of 1 ng, which is a good result when compared with other serological assays.

Animals↗