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951.
Isolation and identification of pathogenic microorganisms at wastewater-irrigated fields: ratios in air and wastewater. 总被引:4,自引:2,他引:2 下载免费PDF全文
B Teltsch S Kedmi L Bonnet Y Borenzstajn-Rotem E Katzenelson 《Applied microbiology》1980,39(6):1183-1190
Samples of air and corresponding wastewater samples were taken at wastewater spray-irrigated fields. The concentrations of salmonellae and enteroviruses present in these samples were determined and compared with those of coliforms, and the ratios between them were calculated. The most common Salmonella serotype in the air was Salmonella ohio, whereas in the wastewater, Salmonella anatum was the most common. Enteroviruses isolated and identified were poliovirus, echovirus, and coxsackievirus type B. From the ratios of salmonellas to coliforms and enteroviruses to coliforms in the air, as compared to these ratios in the wastewater, it was concluded that the suitability of coliforms as an indication of airborne contamination caused by spray irrigation is questionable. 相似文献
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Palsamy Kanagaraj Amandine Gautier-Stein Dietmar Riedel Christoph Schomburg Joan Cerdà Nadine Vollack Roland Dosch 《PLoS genetics》2014,10(6)
During oogenesis, the egg prepares for fertilization and early embryogenesis. As a consequence, vesicle transport is very active during vitellogenesis, and oocytes are an outstanding system to study regulators of membrane trafficking. Here, we combine zebrafish genetics and the oocyte model to identify the molecular lesion underlying the zebrafish souffle (suf) mutation. We demonstrate that suf encodes the homolog of the Hereditary Spastic Paraplegia (HSP) gene SPASTIZIN (SPG15). We show that in zebrafish oocytes suf mutants accumulate Rab11b-positive vesicles, but trafficking of recycling endosomes is not affected. Instead, we detect Suf/Spastizin on cortical granules, which undergo regulated secretion. We demonstrate genetically that Suf is essential for granule maturation into secretion competent dense-core vesicles describing a novel role for Suf in vesicle maturation. Interestingly, in suf mutants immature, secretory precursors accumulate, because they fail to pinch-off Clathrin-coated buds. Moreover, pharmacological inhibition of the abscission regulator Dynamin leads to an accumulation of immature secretory granules and mimics the suf phenotype. Our results identify a novel regulator of secretory vesicle formation in the zebrafish oocyte. In addition, we describe an uncharacterized cellular mechanism for Suf/Spastizin activity during secretion, which raises the possibility of novel therapeutic avenues for HSP research. 相似文献
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J.-P. Périn F. Bonnet P. Jollès 《International journal of biological macromolecules》1981,3(5):303-310
The protein-keratan sulphate core has been obtained by chondroztinase treatment of the proteoglycan monomers. The hyaluronic acid-binding region of the proteoglycans was prepared by trypsin treatment of the proteoglycans under their associated form. Both preparations were submitted to cyanogen bromide treatemnt. The fragments were separated by gel filtrations and polyacrylamide gel electrophoreses. The protein-keratan sulphate core gave rise to two main classes of fragments: the larger ones apparently arose from the polysaccharide attachment region of the monomers; among the smaller ones four appeared to be connected to one of the larger fragments by disulphide bridges. The hyaluronic acid-binding region gave rise to fragments whose electrophoretic mobilities were similar to those of some of the smaller fragments characterized in the cyanogen bromide treated protein keratan sulphate core. The molecular weights as well as the amino acid and sugar compositions of all the cyanogen bromide fragments are reported. 相似文献
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X. Bonnet R. Shine G. Naulleau M. Vacher-Vallas 《Proceedings. Biological sciences / The Royal Society》1998,265(1392):179-183
Because snakes have a highly simplified morphology, and many species have a wide (and broadly overlapping) range of adult body sizes within each sex, they offer an excellent opportunity to compare body composition of males and females. Evolutionary theory predicts that particular body components should be differentially enlarged in the two sexes. For example, we might expect the reproductive success of females to be enhanced by enlargement of organ systems involved in the processing and storage of energy (e.g. alimentary tract, liver, fat stores) whereas males would benefit from the enlargement of systems important for mate-searching, male–male combat and sperm competition (e.g. larger mass of skeletal muscles, tail, and kidneys). Dissection of 243 specimens of three snake species (117 Vipera aspis, 43 Elaphe longissima, 83 Coluber viridflavus) broadly supported these predictions. Strong sex differences were apparent in relative sizes (masses) of all the non-gonadal body components that we weighed. For example, males consistently had more musculature (relative to body length) than did conspecific females. Dimorphism in relative muscle mass is likely to be one of the most fundamental and widespread morphological differences between males and females in the Animal Kingdom. 相似文献
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M. Tamarelle M. L. Sallafranque J. P. Benedetto J. Bonnet J. Vieillemaringe J. Girardie 《Histochemistry and cell biology》1990,95(2):195-203
Summary A tryptophanyl-tRNA synthetase (TrpRS)-immunoreactivity is localized in various neurosecretory cells of all ganglia of the central nervous system of the Orthoptera Locusta migratoria, except in deutocerebrum, and in endocrine cells of the midgut. It has been observed that TrpRS-like material never co-localizes either with CCK-like or octopamine-like material.TrpRS immunoreactive perikarya and processes that ramify extensively throughout the neuropiles have been detected in the protocerebrum, optic lobes, tritocerebrum, suboesophageal, thoracic and abdominal ganglia. In the lateral protocerebrum, a particular TrpRS pathway different from the lateral gastrin cholecystokinin (CCK-8(s)) pathway is revealed, certain of these processes terminating in the glandular part of the corpora cardiaca. In the metathoracic ganglion, have been observed numerous immunoreactive cell bodies and processes in the neuropiles. Some of them constitute a major pathway and which are distinct from octopamine (OA) cells but in close vicinity with the latter. In the midgut immunopositive TrpRS-like cells are dispersed among the regenerative and digestive cells of the epithelium; they are different from gastrin-cholecystokinin positive cells.The various TrpRS-like immunoreactivities identified in Locusta indicate that TrpRS-like material may occur in different tissues of organisms other than Vertebrates. These results suggest also that TrpRS-like enzyme could be involved in functions other than aminoacylation, as in Vertebrates. 相似文献