Investigations on the specificity of thiophilic interaction for monoclonal antibodies of different subclasses.

A comparative study was carried out to investigate the influence of different mouse antibody subclasses on the chromatographic behaviour on thiophilic supports. Cell-free supernatants from different mouse-mouse hybridoma cultures in a standard medium were purified on thiophilic agarose and Fractogel EMD TA. The adsorption capacities and purification factors were monitored under optimised adsorption conditions. The different isotypes did not differ significantly regarding capacity of the thiophilic matrix, but the purity of the eluted antibody fractions was significantly lower for the IgG2a subclass compared to all other murine antibodies. A significant copurification of proteins from cell culture supernatant with antibodies of the IgG2a subclass indicated a restriction in the universal nature of thiophilic interaction.

[Isolation and characterization of glycerol dehydrogenase from bacillus megaterium]. / Isolierung und Charakterisierung von Glycerin-Dehydrogenase aus Bacillus megaterium.

Glycerol dehydrogenase of high purity was isolated from Bacillus megaterium. The enzyme has a pH optimum of 9 and dehydrogenizes in presence of NAD+ glycerol as well as 1,2-propanediol and, to a smaller extent, erythritol. The Michaelis constant for glycerol is 1.4 X 10(-3)M and for NAD+ 3 X 10(-4)M. With the application of different methods (density gradient centrifugation, gel electrophoresis and gel chromatography) relative molecular masses of 156 000-160 000 were ascertained. In the dodecyl sulfate electrophoresis we found a molecular mass of 38 000 per subunit, so that the native enzyme is existent in the tetrameric form. By means of fluorescence titration one NADH binding site per subunit could be estimated. The amino-acid composition was determined. The enzyme is stable only in the presence of high thiol concentrations. Heavy metal ions and chelating agents inhibit the activity of the enzyme. Zinc, presumably, is the natural heavy metal in the active center, but other divalent metal ions can also activate the apoenzyme. With the help of chemical modification reactions, the probable presence of one essential thiol group and one essential tyrosine residue per subunit could be demonstrated.

Diaphragmatic hernia in bovines.

Three cases of diaphragmatic hernia in bovines were encountered over a period of 5 years. The successful surgical repair of one case is reported.

Embryonal rhabdomyosarcoma. A case report.

A patient with embryonal rhabdomyosarcoma, who presented with septic criminal abortion, is discussed. The fact that the correct diagnosis was obscured by the unusual sequence of events is commented upon, and the need for critical evaluation of apparently clear-cut cases is demonstrated.

[Hair growth on pedunoular skin flaps in the guinea pig]. / Uber das Haarwachstum auf gestielten Hautlappen beim Meerschweinchen

In animal experiments with 12 male guinea pigs skin defects have been covered with one-sided bridge flaps. As opposed to corresponding earlier investigations on free full thickness skin autografts no irreversible and much less reversible damage to the hair follicles could be demonstrated in these skin flaps in the primary postoperative phase. In the later postoperative phase, there was--similar to the free full thickness skin autografts--a synchronization of hair change over several cycles, but on the other hand there was no precipitation of hair change. As a result of these findings it may be assumed that the secondary damage to the hair follicles in the later postoperative phase is not as pronounced in these flaps as in free full thickness skin autografts.

[A glucose dehydrogenase for the determination of glucose concentrations in body fluids (author's transl)]. / Eine Glucose-Dehydrogenase für die Glucose-Bestimmung in Körperflüssigkeiten

The isolation of glucose dehydrogenase from Bacillus megaterium M 1286 is outlined. Data on the specificity of the enzyme towards carbohydrates are given. A specific method for glucose determination using this enzyme was developed. Methods and results of four variants of this glucose determination are presented: End point determination in the UV range, determination with formazan as reaction product, kinetic determination in the UV range, and continuous flow analysis in the UV range (AutoAnalyzer method).