Showing papers by "University of Düsseldorf published in 1972"

Effects of norepinephrine, theophylline and dibutyryl cyclic AMP on in vitro lipolysis of human adipose tissue in obesity.

Abstract: Lipolysis (release of glycerol and free fatty acids) of subcutaneous human adipose tissuein vitro has been investigated in relation to relative body weight and fat cell size. Studying 86 persons, there was a highly significant logarithmic relation between relative body weight, fat cell size and lipid content of subcutaneous adipose tissue obtained from the abdominal region. Even in extreme obesity a mean fat cell diameter of 135 μ was generally not exceeded. In these cases overweight is due to hypertrophy as well as hyperplasia of adipose tissue. — The basal FFA and glycerol release, calculated on the basis of the lipid content, did not significantly differ in normal and overweight persons. The lipolysis of the individual cell increased, however, with increasing cell diameter. The quotient of resterification (FFA release: glycerol release) was significantly lower in obesity. — When lipolysis was stimulated with norepinephrine, theophylline or dibutyryl-cyclic AMP, the dose response relations were similar in obesity and normal weight. — The stimulation of lipolysis, expressed as % of baseline, was diminished in obesity. Stimulation with dibutyryl-cyclic-AMP was negatively correlated to the cell diameter. — The absolute release of metabolites per fat cell after stimulation with norepinephrine, theophylline or dibutyryl-cyclic AMP was positively correlated with the fat cell diameter. — Addition of glucose resulted in an increment in glycerol release and an inhibition of FFA release. However, the correlation of lipolysis with fat cell diameter was not affected. — The observations suggest that large fat cells are provided with additional total lipase. Under basal conditions the relation of inactive pro lipase to active lipase seemed to change in favour of the active enzyme.

Hydrogen and Proton Transfer Across the Chloroplast Envelope

Abstract: The chloroplast stroma is separated from the cytoplasmic compartment of leaf cells by the chloroplast envelope which exerts control functions in leaf metabolism in that it permits passage of some metabolites, but not of others. The chloroplast envelope has been found to be practically impermeable to oxidized and reduced pyridine nucleotides (HEBER & SANTARIUS 1965, ROBINSON & STOCKING 1968, MATHIEU 1967). Still, some communication between chloroplastic and cytoplasmic redox potentials does exist. In this contribution indirect transfer of hydrogen across the chloroplast envelope via cyclic transport metabolite systems is discussed. Proton transfer across the chloroplast envelope is also considered, since protons are reactants in redox reactions which form part of indirect transfer systems.

Antagonistic factors in the pathogenesis of coal workers' pneumoconiosis

Abstract: At first sight it appears paradoxical to study the etiology and pathogenesis of coal workers’ pneumoconiosis in animals by administering quartz dust and mixed dusts containing quartz intraperitoneally, rather than intratracheally or by inhalation. But, as revealed by our group, it is much easier to observe the typical tissue response to dusts in omentum and in lymph nodes than in the lungs. It will be demonstrated, on the basis of “short-term” and “long-term” experiments that the difference between the cell reactions to pure quartz and that to mixed dusts containing quartz is only a temporary one and that polyvinylpyridine-N-oxide (PVNO) modifies these reactions or prevents them from occurring. Part of the long-term experiments have been presented in earlier publications.o--R In this communication, further details of these experiments are reported.

Note on Tests Concerning the G Index of Agreement

Abstract: it is the difference between the frequencies of the homonymly assigned cells (++ and --) and the heteronymly assigned cells (+and ―+) in a four-fold contingency table. This name seems to be more descriptive than the name Index of agreement, which is restricting the index to the cases of agreement between placements. Whether or not such an index is more adequate in describing the relationship between two characteristics in N individuals or between two persons on n items than is the phi or the tetrachoric correlation coefficient (c.f., Cliff, 1962; Holley, 1964) is a matter of methodological consideration. Within this consideration, the formal question arises, how to decide whether or not an observed G index is significantly different from an expectation of zero under the null hypothesis.

Funktionelle Behandlung der Hüftgelenksdysplasie und Hüftverrenkung mit dem Hanausek-Apparat

Abstract: Schlechte Fruh- und Spatergebnisse bei der „klassischen“ Huftluxationsbehandlung und Fruhoperation veranlasten uns, im Fruhjahr 1969 zu einer vorwiegend konservativen funktionellen Behandlungsmethode uberzugehen. Die Behandlung mit dem Hanausek-Apparat, der schon seit 30 Jahren in der Tschechoslowakei erfolgreich eingesetzt wird, muste allerdings gewissen Modifikationen unterworfen werden, weil unsere Luxationskinder infolge verspateter Diagnose bei Therapiebeginn wesentlich alter waren als dort. Unser Behandlungsschema, das sich bisher als zweckmasig erwiesen hat, wird erlautert.

Contrast effects in the child’s judgment of lifted weight

Abstract: In this study on anchor effectiveness, the hypothesis that the locus of inflection points of adaptation level varies with chronological age was tested and confirmed. Altogether 62 Ss, divided into four age groups (4;8-12;11 years) had to judge either a 20- to 180-g weight series or a 200- to 400-g series, with anchor values ranging either from 95 to 1700 g or from 16 to 270 g, according to Helson’s standard experimental paradigm which was slightly modified with regard to children’s testing perceptual response. For children more than 7;0 years old, the anchor-AL trend follows a cubic trend, whereas for younger Ss a monotonic contrast effect trend was obtained. These results are interpreted in terms of cognitive rather than sensory contrast effects in psychophysics.