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H Beeser

Publications and source records attributed to H Beeser.

12 recordsLinked to original sources
PubMed1991

Influence of different surfactants on the separation of von Willebrand factor multimers by use of agarose gel electrophoresis and semi dry blotting technology.

The separation of vWF-multimers by use of sodium dodecyl sulfate (SDS) agarose gel electrophoresis and semi dry blotting instead of tank blotting procedure has been studied. We could demonstrate, that multimers in the range of highest molecular weights could not be visualized using this technique. Therefore we have investigated the influence of different types of anionic surfactants on the separation of vWF-multimers and could show that the hydrophilic/lipophilic balance (HLB) is an important value to characterize the capacity of a surfactant to separate vWF-multimers. The best separation quality was achieved with sodium dodecyl benzene sulfonate (SDBS). This surfactant is a superior alternative to SDS in separating vWF-multimers of the highest molecular weights.

Benzenesulfonates↗
PubMed1990

Biosynthesis and secretion of M- and Z-type alpha 1-proteinase inhibitor by human monocytes. Effect of inhibitors of glycosylation and of oligosaccharide processing on secretion and function.

The biosynthesis and secretion of M-type and Z-type alpha 1-antitrypsin was studied in human monocytes. In monocytes of PiMM individuals alpha 1-antitrypsin represented 0.08% of the newly synthesized proteins and 0.44% of the secreted proteins. Two molecular forms of alpha 1-antitrypsin could be identified: a 51-kDa intracellular form, susceptible to endoglucosaminidase H, thus representing the high-mannose type precursor form and a 56-kDa form resistant to endoglucosaminidase H which was secreted into the medium. Inhibition of de novo glycosylation by tunicamycin impaired the secretion of M-type alpha 1-antitrypsin by about 75% whereas inhibition of oligosaccharide processing by the mannosidase II inhibitor swainsonine did not alter the secretion of M-type alpha 1-antitrypsin. alpha 1-Antitrypsin secreted by human monocytes was functionally active as measured by complex formation with porcine pancreatic elastase. Even unglycosylated alpha 1-antitrypsin secreted by human monocytes treated with tunicamycin formed a complex with elastase. In monocytes of PiZZ individuals the secretion of alpha 1-antitrypsin was decreased. 72% of newly synthesized M-type alpha 1-antitrypsin, but only 35% of newly synthesized Z-type alpha 1-antitrypsin were secreted during a labeling period of 3 h with [35S]methionine. The 51-kDa form of Z-type alpha 1-antitrypsin accumulated intracellularly, whereas the 56-kDa form was secreted. Inhibition of oligosaccharide processing by swainsonine did not alter the decreased secretion of Z-type alpha 1-antitrypsin, whereas inhibition of de novo glycosylation by tunicamycin blocked the secretion of Z-type alpha 1-antitrypsin completely.

Alkaloids↗
PubMed1988

Long-term stability of international reference preparations for thromboplastins.

Three certified reference materials for thromboplastins are available from the Community Bureau of Reference (BCR) of the European Commission for calibration of commercial thromboplastins used for control of oral anticoagulant therapy. The long-term stability of these reference materials has been monitored by two independent laboratories, using deep-frozen and lyophilized plasma samples. Prothrombin times and prothrombin time ratios measured on 19 occasions in the period 1981-86 have been analysed for trend with time. Although significant trends of prothrombin time and ratio (P less than 0.05) were observed, a consistent pattern of trends could not be recognized. The significant trends of prothrombin time and prothrombin time ratio are most probably due to changes in local laboratory conditions. There is no indication that the reference materials have deteriorated since the beginning of the study. It is recommended that long-term stability monitoring of thromboplastins be performed by at least two laboratories simultaneously.

Drug Stability↗
PubMed1987

Repression of alpha 2-macroglobulin and stimulation of alpha 1-proteinase inhibitor synthesis in human mononuclear phagocytes by endotoxin.

Mononuclear phagocytes are a bone-marrow-derived subgroup of white blood cells which circulate as monocytes and, after differentiation into macrophages, become resident in many tissues. By synthesizing the important proteinase inhibitors alpha 2-macroglobulin and alpha 1-proteinase inhibitor mononuclear phagocytes contribute to the control of proteolysis both in blood and tissues. Applying a culture system which enables human blood monocytes to differentiate into macrophages in vitro, synthesis of alpha 2-macroglobulin and alpha 1-proteinase inhibitor was studied. The normal course of monocyte-macrophage maturation is accompanied by a strong increase of specific alpha 2-macroglobulin synthesis and a concomitant slight decrease of alpha 1-proteinase inhibitor. alpha 2-Macroglobulin can be designated as a marker protein of the monocyte/macrophage differentiation. Endotoxin (Salmonella typhi) in a concentration as low as 100 ng/ml strongly represses alpha 2-macroglobulin synthesis both in monocytes and macrophages. Furthermore, endotoxin completely abolishes the induction of alpha 2-macroglobulin synthesis during the course of normal monocyte in vitro cultivation, indicating that endotoxin is a strong inhibitor of the monocyte-macrophage maturation. In contrast to alpha 2-macroglobulin, alpha 1-proteinase inhibitor synthesis is strongly stimulated by endotoxin in monocytes as well as in macrophages.

Blood Proteins↗