Synthesis and loss of activity of glucose-6-phosphate dehydrogenase in dividing plant cells

1. Using the technique of density-labelling with deuterium oxide, evidence has been obtained for the de novo synthesis of glucose-6-phosphate dehydrogenase (D-glucose-6-phosphate:NADPH+ 1-oxidoreductase, EC 1.1.1.49), during the culture of synchronously growing plant cells. 2. The entire increase in enzyme activity during the early cell cycles in this material can be accounted for by the appearance of an enzyme species with increased buoyand density. 3. A method is described for resolving overlapping distribution profiles after density centrifugation, which allows estimation of the amount of each species present at different times, and calculation of the loss of activity of the light species present from the start of culture. 4. Loss of activity of glucose-6-phosphate dehydrogenase in normal growing conditions in the presence of 2,4-dichlorophenoxyacetic acid is very much faster than in conditions which do not lead to cell division: in the absence of 2,4-dichlorophenoxyacetic acid, or in the presence of the inhibitor of RNA synthesis, 6-methylpurine.     

Dissociation of beta-hydroxy-beta-methylglutaryl-CoA reductase activity from the overall rate of cholesterol synthesis in the liver following the intravenous administration of lipid

After the intravenous administration to the intact rat of triglyceride carried in either intestinal lipoproteins or in an artificial fat emulsion, the enzymatic activities of microsomal beta-hydroxy-beta-methylglutaryl-CoA reductase activity in the liver assayed in vitro became markedly elevated. This elevation of enzyme activity was not associated with a corresponding change in the overall rate of cholesterol synthesis in the rat liver slice as measured by the incorporation of either [3H]water or [1-14C]octanoate into nonsaponifiable lipids or into digitonin-precipitable sterols. The degree of dissociation of hydroxymethylglutaryl-CoA reductase activity from the overall rate of cholesterol synthesis correlated closely with the amount of lipid administered to the animal, the level of circulating lipids, and the level of ketone synthesis manifest in the liver cell suggesting that this phenomenon might be the consequence of a detergent effect of elevated cellular levels of fatty acids. In any event, under these experimental circumstances hydroxymethylglutaryl-CoA redutase activity no longer reflects the rate at which the liver cell is synthesizing cholesterol.     

Cathepsin D from horse spleen. I. Purification and study of certain physicochemical properties

Horse spleen cathepsin D (3.4.23.5.) was purified from crude extract by sodium chloride and ethanol precipitation, column chromatography fractionation on DEAE cellulose and CM Sephadex, re-chromatography on DEAE cellulose and gel filtration. The enzyme has been purified about 3.000 folds with a yield of 30 per cent. The purified enzyme seems to be homogeneous on Sephadex G100, one protein band is apparent on disc electrophoresis. Determined by dansylation the N-terminal amino acid is glycine. A molecular weight of 42,500 +/- 3,000 was obtained with Sephadex G100 gel filtration and light scattering measurements. Amino acid analysis and chemical determinations were performed: cathepsin D is a glycoprotein (2 or 3 osamine residues) including 344 amino acids and 4 disulfide bonds. Spectrophotometric data show that E1cm/1 mg/ml = 1.01 at lambda = 280 nm. ORD measurements indicate about 20 per cent of helicoidal content in the molecule.     

Emergency open lung biopsy

Twenty-eight patients underwent open lung biopsy on an emergency basis. The clinical course in each case was deteriorating rapidly, and all were in respiratory failure. The correct diagnosis was established in 96% of the biopsies (27 of the 28 patients). The clinical diagnosis prior to biopsy was in error or incomplete in 15 (55%) of the patients. Specific therapy was lifesaving in 12 of the 28 patients. The value of the procedure outweighed the complications. Thrombocytopenia and positive end-expiratory pressure ventilation were not contraindications to biopsy.     

Recto-sigmoid carcinoma after uretero-sigmoidostomy. One case, with a review of the literature (author's transl)

A case of recto-sigmoid adenocarcinoma, developing 25 years after bilateral uretero-sigmo dostomy for extrophia vesicae in a 29 year old man. A study of the literature emphasises the long delay before its appearance, the gastrointestinal nature of the tumour and its grave prognosis. The pathogenesis of this lesion is unknown at present, and consideration should be given to the effects of urine on the digestive mucosa and the role of a possible inflammatory granuloma, but also the possibility of a urinary tract origin, despite the apparent histological contradiction.     

Sexual education and contentment with the feminine sexual role (author's transl)]

The correlation of sexual education during childhood and the later contentment with the feminine sexual role was quantitively tested for its statistical significance. The data were collected for 386 women with a questionnaire and psychometric testing. Contentment with the feminine sexual role showed correlations to the age of the first sexual education (p smaller than 0.01), to the quality of the sexual education (p smaller than 0.05) and to the experience of the individual sexuality during adolescence (p smaller than 0.05). The earlier and the more positive the sex education the higher was the contentment with the own sexual role. Women who were most content with their presently experienced sexuality were also most content with their social role (p smaller than 0.01). Of importance in the discussion of the results were relationships between the contentment with the sexual role and the age (p smaller than 0.05), neurotic personality traits (p smaller than 0.01), obesity (p smaller than 0.01), psychosomatic complaints (p smaller than 0.05) and the present state of health (p smaller than 0.001). These results are of practical importance for sexual councelling in gynaecology.     

Diphosphonate treatment of Paget's disease

Ethane-1-hydroxy-1, 1-diphosphonate (EHDP) was administered in a dose of 20 mg/kg/d to 21 patients with symptomatic Paget's disease. All patients were treated for 6 months and then followed for an additional 6 months. There was a striking decline in serum alkaline phosphatase and urinary hydroxy-proline excretion observed after 3 months of therapy which was not significantly improved in the succeeding 3 months. Concomitantly there was marked improvement in clinical symptoms and bone scans. Following cessation of therapy, continued biochemical and clinical evidence of remission persisted. Several patients on repeat treatment with EHDP appeared to respond promptly. Side effects were minimal except for a possibly related osteomalacia and increased incidence of pathologic fractures.