Ultrastructural lesions in Mycoplasma pneumoniae membranes produced by antibody and complement

Lesions in Mycoplasma pneumoniae membranes were produced by antibody and either human or guinea pig complement and were observed by electron microscopy after negative staining. These defects measured approximately 9.0 to 10.0 nm in diameter-slightly more for human complement than for guinea pig complement. The development of these small lesions was accompanied by a decrease in the viability of the organism.

Novel System for Improved Control of Filamentous Microorganisms in Continuous Culture

We describe a system devised to overcome the tendency of fungal mycelium grown in continuous cultures to adhere to the walls and hamper the outflow of the fermentation vessel, with resulting difficulties in attainment of true steadystate conditions.

Immunogenicity and specificity of collagen. XII. Demonstration by immunofluorescence and haemagglutination of antibodies with different specificity to human collagen

A comparative investigation, using haemagglutination, haemagglutination-inhibition and immunofluorescence, was performed for demonstration of antibodies with different types of collagen specificity. In rabbit antisera to acid-soluble human collagen a fraction of species-specific antibodies to human collagen and a fraction of general, non-species-specific collagen antibodies could be demonstrated in good accordance by both techniques. Calf, rabbit, rat and guinea-pig collagen were used as heterologous control preparations.

Antihypertensive and noradrenaline-depleting effects of guanethidine metabolites

The antihypertensive and myocardial noradrenaline-depleting activities of the three identified guanethidine metabolites were compared with those of guanethidine itself. Metabolite A (guanethidine-N-oxide) and Metabolite B [2-(6-carboxylamino)ethylguanidine] both showed approximately 1/30th of the antihypertensive effect of guanethidine in rats. Metabolite A, but not Metabolite B, caused a depletion of cardiac noradrenaline stores. The intensity of this effect was between 1/10th and 1/30th that of guanethidine. Metabolite C [(6-carboxyhexyl)-2-iminoimidazolidine] was inactive on both parameters. [3H]Noradrenaline uptake into isolated bovine nerve granules was not impaired by either guanethidine or its metabolites. It is concluded that the antihypertensive and myocardial noradrenaline depleting effects of guanethidine are produced by the unchanged drug rather than by one of the identified metabolites.

Elektron-eiektron-doppelresonanz mit hilfe einer neuartigen mikrowellen-briickcn-anordnung

A new type of X-band microwave bridge is described. It consists of a cavity and a helix arranged in an orthogonal manner in order to obtain maximal decoupling.

A variable frequency double resonance spectrometer com­prising this arrangement is used to measure ELDOR of free radicals in solution