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K Jobst

Publications and source records attributed to K Jobst.

At least 37 records · Page 2Linked to original sources
PubMed1991

The reaction of reducing sugars with histones.

The epsilon amino groups of histone proteins were eliminated by condensation with glucose, fructose or mannose. The trichloroacetic acid extracted, DNA negative nuclei treated with reducing sugars, stained easily with basic dyes.

Carbohydrates↗
PubMed1990

Identification of nucleohistones by glycosylation and basic dyes.

Earlier examinations have shown that reducing sugars mainly react with the epsilon-amino group of lysine. After DNA extraction, lysine-rich histone proteins of alcohol fixed nuclei of rat organs were treated with glucose-6-phosphate. It was possible to selectively stain the histone type proteins of DNA negative nuclei with basic dyes.

Animals↗
PubMed1989

Unequal expression of complement C4A and C4B genes in rheumatoid synovial cells, human monocytoid and hepatoma-derived cell lines.

C4A and C4B are closely related homologous complement proteins encoded in the class III region of major histocompatibility complex (MHC). The regulation of their expression is under genetic and hormonal control. In this study we investigated the synovial fluid plasma ratio of C4A and C4B of rheumatoid (RA) and osteoarthritis (OA) patients, and a predominance of the C4B gene expression by the synovial macrophages of RA patients was demonstrated. To clarify the tissue specificity of the expression of C4A and C4B genes, human monocytoid cell line U937 and hepatoma-derived HepG2 cells were studied. The gene expression of C4A and C4B were markedly different in these cells since a relative predominance of C4B mRNA in U937 cells and excess of that of C4A in HepG2 cells were detected. Recombinant interferon-gamma (IFN-gamma) up-regulated the expression of C4A gene in both cells, but had apparently no effect on the C4B gene. Our results demonstrate dissimilar expression patterns for the two human C4 genes, suggesting different tissue specific regulation of human C4A and C4B.

Anaphylatoxins↗
PubMed1989

Luminol dependent chemiluminescence of quartz and zymosan stimulated neutrophils.

The effect of the opsonization by zymosan and quartz particles on the chemiluminescence was investigated on human neutrophil granulocytes. Opsonization of zymosan enhanced the chemiluminescence response, while opsonized quartz inhibited the chemiluminescence reaction. Calcium ionophore A 23187 treatment did not influence the chemiluminescence of quartz but the light signal in the presence of quartz decreased rapidly. In parallel experiments the protein pattern of zymosan treated neutrophils was investigated by high resolution two-dimensional polyacrylamide gel electrophoresis.

Blood Proteins↗
PubMed1989

Cell analysis in clinical chemistry.

The present state and the future of clinical chemistry are considered. Attention is called to the diagnostic value of chemical analysis on cellular level and the procedures designed for such examinations so far are described. The author's results obtained by fluorescence polarisation and bioluminescence are presented. Novel analytical trends, whose introduction into clinical chemistry may be expected greatly to promote diagnostics through our knowledge of intracellular events, are touched upon.

Cells↗
PubMed1988

Bioluminescent monitoring of ATP release from human red blood cells treated with nonionic detergent.

The adaptation of the firefly luciferin-luciferase system for the detection of ATP in the presence of Triton X 100 or Brij 58 nonionic detergents is described. The method is sensitive, easy to perform and is suitable for the continuous monitoring of the mobilization rate of ATP from Triton X 100- or Brij 58-treated human erythrocytes. A very rapid ATP release was observed after Triton X 100 treatment of the red blood cells while the presence of Brij 58 caused a retarded mobilization of the intracellular ATP. The technique described seems to be applicable to all kinds of cells.

Adenosine Triphosphate↗
PubMed1987

The bulk of ATP is associated to proteins in the living cell: a release kinetics study.

The analysis of the nonionic detergent induced release kinetics of intracellular components is a promising approach to obtain information on the possible molecular interactions inside the living cell. The molecular interactions of ATP were studied by monitoring the nonionic detergent-induced release kinetics of ATP from cultured human cells. The observed rapid mobilization rate in the presence of Triton X 100 and the retarded release in the presence of Brij 58 were in good agreement with the detergent-induced release kinetics of proteins and K+ reported earlier. These data are consistent with the idea that the bulk of ATP is associated to the protein macromolecules of the living cell.

Adenosine Triphosphate↗
PubMed1986

Cocompartmentation of proteins and K+ within the living cell.

Monolayer H-50 tissue culture cells were treated with Triton X-100 and Brij 58 nonionic detergents, and their electron microscopic morphology along with the release of the intracellular proteins and K+ were studied. Although Triton X-100 was more effective, both detergents removed the lipoid membranes within 5 min. The mobilization and solubilization of the cytoplasmic and nuclear proteins occurred much faster with Triton X-100 than with Brij 58. In Triton X-100-treated cells, the loss of K+ was complete within 2 min. The loss of K+ from the Brij 58-treated cells was complete only after 10 min and the mobilization of K+ showed sigmoid-type release kinetics. These results support the view that most of K+ and "diffusible" proteins not freely dissolved in the cellular water, but they are cocompartmentalized inside the living cell.

Animals↗
PubMed1986

Erythrocyte transketolase activity in patients with chronic renal disease.

B1 vitamin deficiency was studied by the erythrocyte enzyme activation test in patients with chronic uraemia. Transketolase activity was measured in the erythrocyte haemolysates of 14 patients with chronic uraemia and in 16 healthy controls in the presence of TPP and following TPP saturation. The magnitude of activity increases as a result of TPP saturation which is probably indicative of an insignificant thiamine deficiency in patients with chronic uraemia.

Chronic Disease↗