Organ culture of rat skeletal muscle subjected to intermittent activity

Zusammenfassung Es wird eine Methode angegeben, um die wichtigen biochemischen und pharmakologischen Untersuchungen an Muskulatur (Rattenmuskel) bei Erhaltung der mechanischen Aktivität über 8 Tage durchzuführen.     

Immunogenicity of fatty acid anilides in rabbits and the pathogenesis of the Spanish toxic oil syndrome

Summary Fatty acid anilides, the major xenobiotic found in the cooking oils responsible for the Spanish toxic oil syndrome, are immunogenic for rabbits as ascertained by a skin test reaction, the characterization of specific antibodies against anilides and the immunofluorescent detection of anilide dependent antigens in tissue slices from treated animals.Acknowledgments. This work was supported by a grant from the Fondo de Investigaciones Sanitarias to the C.S.I.C. Programme on Toxic Oil Syndrome. We are indebted to Dr M. Studt and Dr E. Fernández-Alvarez, from the National Center for Organic Chemistry, C.S.I.C., for kindly providing the synthetic fatty acid anilides. We also wish to thank Prof. C. Gitler for helpful discussion.     

Effects of 2-β-D-glucosyl-4-hydroxy-7-methoxy-1,4-benzoxazin-3-one onSchizaphis graminum (rondani) (insecta,aphididae) feeding on artificial diets

Summary 2--Glucosyl-4-hydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA-Glc), the main hydroxamic acid from maize and wheat, and its aglucone, decreased survival ofSchizaphis graminum reared on artificial diets. Both compounds were toxic for aphids and acted as feeding deterrents, at concentrations as low as 1 mM. The natural concentrations of glucosides of hydroxamic acids in wheat leaves reach up to 6 mmoles/kg fresh weight, thus falling within the range in which DIMBOA-Glc causes delecterious effects to diet-fed aphids.To whom correspondence should be addressed. THis work was supported by grants from International Foundation for Science (484), Universidad de Chile (N-1654) and the Agency for International Development.     

Sequencing of Aspergillus nidulans and comparative analysis with A. fumigatus and A. oryzae

The aspergilli comprise a diverse group of filamentous fungi spanning over 200 million years of evolution. Here we report the genome sequence of the model organism Aspergillus nidulans, and a comparative study with Aspergillus fumigatus, a serious human pathogen, and Aspergillus oryzae, used in the production of sake, miso and soy sauce. Our analysis of genome structure provided a quantitative evaluation of forces driving long-term eukaryotic genome evolution. It also led to an experimentally validated model of mating-type locus evolution, suggesting the potential for sexual reproduction in A. fumigatus and A. oryzae. Our analysis of sequence conservation revealed over 5,000 non-coding regions actively conserved across all three species. Within these regions, we identified potential functional elements including a previously uncharacterized TPP riboswitch and motifs suggesting regulation in filamentous fungi by Puf family genes. We further obtained comparative and experimental evidence indicating widespread translational regulation by upstream open reading frames. These results enhance our understanding of these widely studied fungi as well as provide new insight into eukaryotic genome evolution and gene regulation.     

Harvesting large amounts of Drosophila embryos at precisely defined stages

Summary A simple method is described which makes it possible to eliminate the retained eggs ofDrosophila melanogaster and to harvest a large amount of embryos at a defined stage of development. It is based upon carbon dioxide anesthesia, which brings about the expulsion of eggs remaining in the uterus.     

A new cellular function for peroxisomes related to oxygen free radicals?

Summary Although in cell biology peroxisomes are still young organelles, it is becoming increasingly clear that they are involved in important cellular functions. Recent results have indicated the presence of the metalloenzyme superoxide dismutase in peroxisomes and the production of superoxide free radicals (O ₂ ^– ) in these oxidative organelles. These findings, together with other experimental evidence, point towards the existence of new roles for peroxisomes in cellular active oxygen metabolism, something that has a potential impact in multiple areas of cell biology, particularly in biochemistry and biomedicine.     

Lesions in suprachiasmatic nuclei simulate effects of pinealectomy on prolactin release in ovariectomized and sulpiride-treated female rats

Summary Previous studies indicate that the pineal gland alters prolactin secretion, and it was suggested that at least part of the effect of the pineal hormone melatonin on prolactin release may be mediated by the hypothalamic structures. In this study, pinealectomy and lesions of the suprachiasmatic nuclei were found to alter serum levels of prolactin in the same direction, an effect that was counteracted by daily afternoon melatonin administration. Melatonin, but not other pineal indoles, also prevented sulpiride-induced prolactin secretion in pinealectomized or suprachiasmatic nuclei-lesioned and ovariectomized rats, which suggested that the pineal gland can modulate prolactin secretion by acting through a dopamine mechanism independent of hypothalamic suprachiasmatic structures.The authors thank Ms Karen Shashok for revising the English style. This work was supported in part by a grant GG85-0168 from the Comisión Asesora de Investigación Cientifica y Ténica. The NIAMDD, through the National Pituitary Agency, supplied the radioimmunoassay materials for prolactin determinations.