A preliminary microspectrofluorometric study of NAD(P) reduction in dibenzo(a, e) fluoranthene-treated single living cells.

The fluorescence increase, due to NAD(P) reduction, following microelectrophoretic injection of glucose 6-P (G6P) into EL2 and NCTC 8739 single living cells treated with diBenzo(ae) Fluoranthene (diB(ae)F) and non-treated, has been studied with a rapid microspectrofluorometer. This study shows the enhanced capacity of treated cells to utilize larger doses (6-10 times more) of G6P than control cells. The time course of the return to the initial fluorescence level is essentially related to the magnitude of the injection dose. There are alterations (e.g. red & blue shifts) in the fluorescence spectrum of diB(ae)F-treated cells before injection and in the increase spectrum after injection of G6P, as compared to the same spectra in the diB(ae)F-untreated cells. This is discussed in reference to the metabolization of diB(ae)F as an alternative pathway for the reoxidation of NAD(P)H.     

Red cell enzyme polymorphism in a Breton population, the Bigoudens

Data are presented on the red cell enzymes of the Bigoudens. Deviations fro the expected Hardy-Weinberg distribution are interpreted as the result of a recent mixing of previously separated groups, in addition to the effect of silent alleles and inbreeding. Special reference to the historical background.     

Cyclo-oxygenase products in carrageenin-induced inflammation

Prostaglandin (PG) E₂, thromboxane (TX) B₂ and the stable breakdown product of prostacyclin, 6-oxo-PGF_1α are present in carrageenin-induced inflammatory exudates. Carrageenin-impregnated polyester sponges were implanted subcutaneously in rats and inflammatory exudates were collected 4–192 h after implantation. The concentrations of cyclo-oxygenase products in sponge fluids was measured by radioimmunoassay after extraction and purification. All three products were detectable after 4 h and reached a peak at 12–24 h. Mean TXB₂ concentrations reached 74 ng/ml at 12 h but decreased to less than 10 ng/ml after 24 h. PGE₂ concentrations were 65 ng/ml at 24 h, after which there was no significant increase and then dropped to about 20 ng/ml between 96 and 192 h. 6-oxo-PGF_1α reached a concentration of 33 ng/ml at 24 h which did not change significantly until levels fell to less than 10 ng/ml between 96 and 192 h. The presence of PGE₂, TXB₂ and 6-oxo-PGF_1α was confirmed by gas-liquid chromatography and mass spectrometry. Total leukocyte numbers increased steadily and were at their highest (116.0 × 10⁶ cells/ml) at 192 h. These results suggest that thromboxanes and prostacyclin, as well as PGE₂, contribute to the acute inflammatory response.     

Relationship between sugar uptake kinetics and total sugar consumption in different industrialSaccharomyces cerevisiae strains during alcoholic fermentation

Summary The sugar transport, fermentative alcohol dehydrogenase (ADH) and protease activities of different industrial strains ofSaccharomyces cerevisiae were measured during batch alcoholic fermentation.These strains exhibited different apparent loss of activity of sugar transport, which seemed to be characteristic of each one. A good correlation was found systematically between the integration of sugar transport activity along fermentation and the maximum amount of sugar consumed during fermentation. In all strains sugar transport activity exhibit a lower half-time than fermentative ADH activity. These progressive declines of both sugar uptake and ADH activities ofSaccharomyces cerevisiae during batch fermentation seemed to not result from an increase in the protease activity.