Maturation of human ovarian follicular oocytes in vitro

Résumé Des ufs oocytes humains obtenus des follicules d'ovaire extraits opérativement ont été cultivés in vitro pour étudier le processus de leur maturation.     

Severe impairment of interleukin-1 and Toll-like receptor signalling in mice lacking IRAK-4

Toll-like receptors (TLRs), which recognize pathogen-associated molecular patterns, and members of the pro-inflammatory interleukin-1 receptor (IL-1R) family, share homologies in their cytoplasmic domains called Toll/IL-1R/plant R gene homology (TIR) domains. Intracellular signalling mechanisms mediated by TIRs are similar, with MyD88 (refs 5-8) and TRAF6 (refs 9, 10) having critical roles. Signal transduction between MyD88 and TRAF6 is known to involve the serine-threonine kinase IL-1 receptor-associated kinase 1 (IRAK-1) and two homologous proteins, IRAK-2 (ref. 12) and IRAK-M. However, the physiological functions of the IRAK molecules remain unclear, and gene-targeting studies have shown that IRAK-1 is only partially required for IL-1R and TLR signalling. Here we show by gene-targeting that IRAK-4, an IRAK molecule closely related to the Drosophila Pelle protein, is indispensable for the responses of animals and cultured cells to IL-1 and ligands that stimulate various TLRs. IRAK-4-deficient animals are completely resistant to a lethal dose of lipopolysaccharide (LPS). In addition, animals lacking IRAK-4 are severely impaired in their responses to viral and bacterial challenges. Our results indicate that IRAK-4 has an essential role in innate immunity.     

Cooperative inhibitory effect of follicular fluid and cAMP on hamster oocyte maturation

Porcine or human follicular fluid inhibited the spontaneous maturation of isolated hamster oocytes in vitro during the first 1.5 h of culture. Moreover, the presence of 50% follicular fluid combined with 100 microM dbcAMP cooperatively reduced the incidence of germinal vesicle breakdown. The addition of FSH also inhibited the resumption of meiosis, and the presence of LH did not overcome the inhibitory effects of follicular fluid and tended to impede isolated hamster oocyte maturation in vitro.     

Mg2+-HCO 3 − -ATPase and carbonic anhydrase in rat intestinal mucosa

Cellular and Molecular Life Sciences - Mg2+-dependent and HCO 3 − -stimulated ATPase activity was highest in the brush border (microvilli) of rat duodenal mucosa compared with that of the...     

Mg2+-HCO-3-ATPase and carbonic anhydrase in rat intestinal mucosa

Mg2+-dependent and HCO-3-stimulated ATPase activity was highest in the brush border (microvilli) of rat duodenal mucosa compared with that of the other gastrointestinal mucosa. This ATPase may be useful to neutralize the gastric acid in the duodenal lumen. Carbonic anhydrase seems to accomplish a subsidiary role in the above reaction.     

Effect of insulin on the synthesis and release of lipid peroxide by cultured hepatocytes isolated from normal and diabetic rats

Summary Lipid peroxide content in hepatocytes isolated from ketotic diabetic rats was higher than normal, and the release of peroxide into the media was also elevated for the initial 18 h. Insulin suppressed both peroxide release and synthesis by cultured hepatocytes isolated from normal and from diabetic rats.     

Inhibitory effect of halocyamine,an antimicrobial substance from ascidian hemocytes,on the growth of fish viruses and marine bacteria

Summary Halocyamine A, an antimicrobial substance isolated from hemocytes of the solitary ascidianHalocynthia roretzi, inhibited in vitro the growth of fish RNA viruses (infectious hematopoietic necrosis virus and infectious pancreatic necrosis virus). Pretreatment of RNA virus with halocyamine A reduced the infectivity of the virus toward host cells. The growth of marine bacteria,Achromobacter aquamarinus andPseudomonas perfectomarinus, was also inhibited by halocyamine A but that ofAlteromonas putrefaciens andVibrio anguillarum was not. These results suggest that halocyamine may have a role in the defense mechanisms ofH. roretzi against marine viruses and bacteria.     

Paroxysmal discharges in the electroencephalogram of the El mouse

Summary The spike discharges in the EEG of the El mouse, a seizure-susceptible strain, were recorded during convulsive seizures. This fact provides evidence that those seizures are really epileptic convulsions.I thank Dr.K. Imaizumi and Dr.K. Nakano of National Institute of Health for their sharing the strain of El mouse to us and MissY. Nakamoto and Mr.N. Ozawa for their technical assistance and Mr.K. Moriyama for his care for the mice, and also thank Dr. H.Narabayashi for his criticism on this paper.