Dietary immunostimulation: interaction with BCG and LPS.

The action of BCG and LPS mR595 used in conjunction with a formula-defined diet is dependent on the administration timing and resembles that of interacting adjuvants affecting different elements of the immune system.     

Photosensitizing furocoumarins: Interaction with DNA and photo-inactivation of DNA containing viruses

Riassunto Le furocumarine possono legarsi in vitro al DNA ed, in misura molto minore, all'RNA. Per irradizione UV (3655 Å) in presenza di psoralene, tre virus a DNA sono stati inattivati, mentre nessun effetto è stato notato su altri tre virus ad RNA.     

Interaction of lead with erythrocytes

Zusammenfassung Untersuchungen mit²⁰³Pb in vitro ergeben, dass Blei in den Erythrozyten vorwiegend an Hämoglobin gebunden wird, während Stromasubstanzen kein Blei aufnehmen.     

Interaction of pepsin with lysozyme

Riassunto L'autore ha studiato il complesso che si forma dall'interazione della pepsina con il lisozima.Vengono riferiti i risultati ottenuti studiando le caratteristiche torbidimetriche, elettroforetiche e di sedimentazione all'ultracentrifuga del complesso pepsinalisozima.Il complesso ha il punto isoelettrico a pH 7.3, ed ha una costante di sedimentazioneS ₂₀=4.9×10^–13.     

Flow microcalorimetric bioassay of polyene antibiotics: Interaction with growingSaccharomyces cerevisiae

Summary Microcalorimetric investigation of the interaction of polyene antibiotics with mid-exponential cells of a growing culture ofSaccharomyces cerevisiae has been used as the basis of a bioassay procedure. The assay is rapid, sensitive and reproducible. The results are compared to classical assays and potency ranking orders.This work was supported by the Science Research Council. (Studentship for B.Z. Chowdhry). We are grateful to the Central Research Fund of London University for funds to purchase the flow nephelometer used to support this study.     

Interaction of vinblastine analogues with tubulin

Summary Studies of the interaction between vinblastine-like alkaloids and their receptor, i.e. tubulin, are reported. They shed some light on the structure-activity relationships in this medicinally important series: the configurations at C₁₄ and C₁₆ as well as the presence of the methoxycarbonyl group on C₁₆ seem to play an essential role in the determination of biological activity.This work was supported by CNRS (A.T.P. No 3232).We thank Dr D. Pantaloni for interesting discussions, Drs N. and Y. Langlois for discussions and for supplying synthetic material, and Eli Lilly Laboratories for gifts of vinblastine, vincristine and leurosidine.     

Interaction of glutaraldehyde with some micro-organisms

Résumé La glutaraldéhyde produit une couleur rouge chez quelques genres de bactéries. Cette couleur est prise par la paroi cellulaire des organismes.     

Dietary restriction and fetal development

Summary The effect of deficient nutrition of pregnant Wistar rats on the fetal weight has been studied. It has been established that the fetal weight of the group of rats fed with a restricted amount of stock diet lags behind the fetal weight of the group receiving unrestricted amounts of the same stock diet. The differences in weight between the 2 groups were, on each day of the observation period, significant at the level of p<0.05 and p<0.01, respectively.This work was supported by a grant of the Republic Research fund of Croatia No. 18-04-06/19-1975.     

Interaction of mitochondrial porin with cytosolic proteins

Summary Intracellular phosphorylation is an important step in active uptake and utilization of carbohydrates. For example glucose and glycerol enter the liver, cell along the extra intracellular gradient by facilitated diffusion through specific carriers and are concentrated inside the cell by phosphorylation via hexokinase or glycerol kinase. Depending on the function of the respective tissue the uptake of carbohydrates serves different metabolic purposes. In brain and kidney medulla cells which depend on carbohydrates, glucose and glycerol are taken up according to the energy demand. However, in tissues such as muscle which synthesize glycogen or like liver which additionally produce fat from glucose, the uptake of carbohydrates has to be regulated according to the availability of glucose and glycerol. How the reversible coupling of the kinases to the outer membrane pore and the mitochondrial ATP serves to fulfil these specific requirements will be explained as well as how this regulates the carbohydrate uptake in brain according to the activity of the oxidative phosphorylation and how this allows glucose uptake in liver, and muscle to persist in the presence of high glucose 6-phosphate without activating the rate of glycolysis.     

Interaction of sulfonylurea with the pancreatic B-cell

Conclusions Sulfonylureas have a variety of effects on pancreatic B-cells. In the present review an attempt has been made to identify those that appear fundamental from a mechanistic point of view and in that sense common to all hypoglycemic drugs tested. On several points the available able experimental information is limited. With this reservation in mind, the following general hypothesis is presented for the insulin-releasing action of this class of drugs. Hypoglycemic sulfonylureas and related [(acylamino)alkyl]benzoic acids bind to the B-cell plasma membrane, a step in which hydrophobic anchoring is essential. Dissociated acidic COOH or SO₂NHCO groups in the drugs are thus presented to an ion-gating protein in the plasma membrane, possibly in the vicinity of a pair of sulfur atoms. The reduced state of these sulfurs is promoted, preventing the formation of a disulfide bridge. K⁺ permeability is thereby decreased, favoring depolarization of the B-cell and Ca²⁺ influx through voltage-dependent channels. Finally, Ca²⁺ triggers the physiological apparatus for discharge of the insulin secretory granules. The effect of this insulinreleasing signal chain is amplified by cyclic AMP which increases in the B-cell as a consequence of depolarization and Ca²⁺ influx. This hypothesis does not attribute an ionophoretic role to the sulfonylureas per sebecause various experiments with cells and artificial membrane systems render such an idea apparently less tenable.