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Biomedical subjects

O W Thiele

Publications and source records attributed to O W Thiele.

At least 19 recordsLinked to original sources
PubMed1986

[Morphologic and lipid chemistry findings in atherosclerotic femoral arteries].

During autopsies of 34 individuals, 110 specimens were taken from femoral arteries and examined by microscopy and lipid chemical analyses. Five types of lesions were differentiated: 1. normal intima, 2. diffuse intimal hyperplasia, 3. fatty streaks, 4. fibrous plaques, 5. atheromatous lesions. Since studies on femoral arteries have not been performed so far, our results were compared with known results from aortas and coronary arteries. However, no essential differences were found by comparing morphologic results and lipid compositions. Esterified and free cholesterol increased approximately 30-fold, phospholipids approximately 6.5-fold, with progressing atherosclerosis. The intima of a 40-year-old alcoholic was found to have an extremely low level of cholesterol esters, while the other findings were not changed.

Arteriosclerosis↗
PubMed1984

Ornithine-containing lipids in Thiobacillus A2 and Achromobacter sp.

20 bacterial strains (corresponding to 16 species) were screened for ornithine lipids. Only two species (Thiobacillus A2 and Achromobacter sp.) turned out to contain ornithine lipids (2.71 mmol/100 g and 0.38 mmol/100 g bacterial dry weight, respectively). In both ornithine lipids, a 3-hydroxy fatty acid was amide-linked to the alpha-amino group of ornithine, a normal fatty acid was ester-linked to the 3-hydroxy group of the former. The predominant fatty acids were 18:1(11) and 3-hydroxy-20:1(13) in Thiobacillus A2, 16:0 and 3-hydroxy-18:1(11) in Achromobacter sp. All monounsaturated fatty acids (with one exception) belonged to the (n-7) family. 11, 12-Epoxy octadecanoic acid was identified among the ester-linked fatty acids of Thiobacillus A2. Phosphatidylcholine was the principal phospholipid in both bacterial species.

Alcaligenes↗
PubMed1984

Isolation and characterization of glycosphingolipids with J blood group activity from bovine spleen.

Two glycosphingolipids with J blood group activity were found in J-positive bovine spleen. They were tentatively identified as ceramide deca- and dodecahexosides containing galactose, glucose, N-acetylgalactosamine and N-acetylglucosamine in a molar ratio of 5:3:1:1 and 6:3:2:1, respectively. Fucose was not present. Ceramide decahexosides without J activity were also found in J-negative bovine spleen. The principal component fatty acids of the J-active glycosphingolipids were saturated even-numbered long-chain acids with 16 to 24 C atoms. Their principal long-chain bases were sphingosine and dihydrosphingosine with smaller amounts of phytosphingosine. Both J-active glycosphingolipids were readily water-soluble and showed strong activity in the bovine J and in the porcine A blood group system. They exhibited no cross-reactivity in the human A system. However, a J-negative glycosphingolipid fraction - also from J-negative spleen - with shorter carbohydrate chain-length showed strong activity in the human A system.

Animals↗
PubMed1984

The transfer of bovine J blood group activity to erythrocytes: chemical nature of transferable and of non-transferable J.

The bovine J blood group substance exists as a glycosphingolipid (ceramide decahexoside as well as ceramide dodecahexoside) and as a glycoprotein. The lipidic form occurs in erythrocyte membranes, both forms are found in serum. The lipidic J substances were isolated from erythrocytes and from serum, and identified by thin-layer chromatography with lipidic J substances isolated from spleen. The glycoprotein nature of the non-lipidic J of serum was evident by pronase-catalysed hydrolysis yielding J-active glycopeptides of lower molecular weights. The lipidic J was completely extracted from lyophilized stroma with chloroform/methanol. From lyophilized serum, however, it was completely extracted only in the presence of water, indicating different binding partners in serum and in erythrocyte membranes. The J lipid was incorporated as intact molecule into the erythrocyte membrane by a simple incubation technique. The incorporation was inhibited by various glycerophospholipids (called blockers). The J glycoprotein could not be transferred to the erythrocyte membrane. Three methods are described which are suitable for the preparation of a blocker-free fraction enriched with J lipids from J-positive serum.

Animals↗
PubMed1982

A nystatin-resistant mutant of Rhodotorula gracilis. Transport properties and sterol content.

A nystatin-resistant mutant of Rhodotorula gracilis was obtained by treatment of the wild strain cells with N-methyl-N-nitro-N-nitrosoguanidine and selected on agar plates containing 150 micrograms nystatin/ml. Three important transport functions of the plasma membrane of mutant cells: the accumulation of monosaccharides, the generation and maintenance of the pH-gradient and of the membrane potential, as well as the cell respiration were insensitive to at least 10(-5) M nystatin. This concentration of nystatin inhibited completely all these processes in wild strain cells. Analysis of cellular sterols revealed a defect of ergosterol biosynthesis in the mutant, which was localized at the last oxidative step between 5,6-dihydroergosterol and ergosterol.

Biological Transport↗
PubMed1982

Chemical characterization of porcine blood serum components with A and SLA activity.

The porcine A blood group substance is found in the serum as a lipid and, additionally, in certain animals, as a glycoprotein. Swine lymphocyte antigens (SLA) occur in the serum only as glycoproteins. Heat treatment of the solid residue obtained by lipid extraction yielded a water-soluble fraction with low protein content, high A activity, but no SLA activity. Poly(glycosyl)ceramides with SLA activity do not occur in the serum; poly(glycosyl)ceramides with A activity cannot be excluded. Desialylation of protein fractions has no effect on A and SLA activity. Both A and SLA activities of protein fractions are stable to mild alkaline hydrolysis thus indicating N-glycosidic carbohydrate-peptide linkages.

ABO Blood-Group System↗
PubMed1982

Quantification of antigens with haemolysing antibodies exemplified by the bovine J blood group system.

1. The J blood group activity of red cells is measured in terms of 50% haemolysis ('direct test'), that of dissolved or suspended samples in terms of 50% haemolysis inhibition ('indirect test') in a standardized bovine J system. 2. The volume of J-containing sample required for a 50% haemolysis inhibition decreases with increasing J activity. 3. The volume of anti-J required for a 50% haemolysis of J-positive erythrocytes also decreases with increasing J activity. 4. The use of antigen units (UAg) was introduced to serve as a measure of J activity of dissolved or suspended samples. 5. Antigen units were also used to characterize J-containing red cells. This was made possible by measuring the relation of the direct test (on red cells). Thus, a relatively simple method of determination of red cell UAg is obtained. 6. It was confirmed by absorption experiments that erythrocytes containing high concentrations of antigen require relatively low amounts of antibody to bring about a 50% haemolysis, but are able to bind a relatively high excess of antibody.

Absorption↗
PubMed1982

The inactivation of the bovine J blood group substance by the periodate ion.

1. Treatment of J-positive (Jcs) bovine erythrocytes with periodate (0.25 mmol/l final concentration, 1 hour, room temperature) has no effect on the J activity. Higher periodate concentrations cause spontaneous haemolyses. 2. Treatment of the lipids extracted from (and containing all J activity of) Jcs erythrocytes with periodate leads to a decrease of J activity even with lower periodate concentrations. 3. Treatment of the stroma prepared from Jcs erythrocytes with periodate demonstrated the relative stability of the J antigen up to 0.25 mmol/l periodate. At the same time the sialic acid concentration of stroma is reduced to about 13% of the initial concentration. 4. Desialylation of Jcs erythrocytes or Jcs stroma with sialidase does not affect the J activity thus confirming previous findings. On the other hand, the J activity of desialylated Jcs stroma is much more susceptible to periodate. 5. It is concluded that membrane-bound sialic acid shields the membrane-bound J antigen from being attacked by periodate.

Animals↗
PubMed1981

Occurrence of phosphatidylcholine in hydrogen-oxidizing bacteria.

15 strains of hydrogen-oxidizing bacteria were grown heterotrophically, harvested during the stationary phase of growth, and analyzed for their principal phospholipids. All strains - with the exception of Corynebacterium autotrophicum strain SA 32 and Pseudomonas pseudoflava - contained phosphatidylcholine as a major constituent. It is concluded that the presence of phosphatidylcholine is neither characteristic of a peculiar bacterial genus or family, nor is it absolutely correlated to the ability to oxidize hydrogen. The phosphatidylcholines of all strains contain C19 cyclopropane acid which is, in some strains, predominantly located at C-2 position of the glycerol moiety.

Bacteria↗
PubMed1980

Bovine J blood-group activity in the lipids of erythrocytes of different age.

J-positive cattle erythrocytes were separated according to age by ultracentrifugation in a discontinuous density gradient of Ficoll-400 (Pharmacia) in isotonic buffer solution. A decrease in phospholipid and in cholesterol content with increasing age was detected. The J activity was found to increase markedly with increasing cell age. This fact supports the view that the in vivo transfer of the J determinant from plasma to erythrocytes is a rather slow process. It is suggested that the increasing J activity of older cells is probably due to a decrease of erythrocyte membrane bound phospholipids which inhibit the transfer of the J determinant to the red cells.

Age Factors↗
PubMed1980

Isolation and characterization of an ornithine-containing lipid from Paracoccus denitrificans.

The isolation and characterization of an ornithine-containing lipid from various strains of Paracoccus denitrificans (grown heteretrophically and autotrophically) is reported. The structure of this aminolipid was found to be H2N--CH2--(CH2)2--CH[NH--CO--CH2--CH(O--CO--R1)--R2]--CO2H, where R1 predominantly represents the residue of octadec-11-enoic acid, R2 the residue of a 3-hydroxyeicos-13-enoic acid. In addition, the major phospholipids (phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol) were isolated and characterized.

Fatty Acids↗
PubMed1979

Studies on the chemical nature of the lipidic J blood-group substance of cattle.

Total lipids extracted from J-positive cattle serum, erythrocytes or spleen exhibit J blood-group activity. The J subsance is concentrated in a lipid fraction obtained by column chromatography. Following mild alkaline hydrolysis or reduction with complex hydrides (LiAlH4, LiBH4), the J activity remains detectable in this lipid fraction even though all acyl ester groups have been destroyed as revealed by ester group determination. This disagrees with the suggestion that fatty acyl esters are essential for J activity. This was confirmed by experiments with a water-soluble J-active product prepared by ozone treatment of glycosphingolipids from bovine spleen. The results of these experiments are in favour of a glycosphingolipid containing anunusually lang oligosaccharide chain. Furthermore, it appears that the terminal moiety of the J determinant is not necessarily an N-acetyl galactosamine unit as suggested previously.

Animals↗