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91.
Prostaglandin D2 was found to be a potent inhibitor of platelet aggregation. Aggregation of human platelets by ADP, collagen and prostaglandin G2 was inhibited more strongly by PGD2 than by PGE1. Although ADP-induced aggregation of rabbit platelets was inhibited more strongly by PGE1 than by PGD2 the latter prostaglandin gave a more long-lasting inhibitory effect on platelet aggregation following intravenous or oral administration. These results coupled with the finding that PGD2 has less hypotensive effects on the cardiovascular system than PGE1 suggest the possible use of PGD2 as an antithrombotic agent. 相似文献
92.
In rat adrenal glands incubated in Locke's solution in vitro norepinephrine and phenylephrine inhibited the release of epinephrine. PGE2 and PGE1 also inhibited the release of catecholamines but PGFα1 had no effect on the adrenal. Thus, catecholamine release from adrenal cells may be regulated by the same mechanisms as in adrenergic nerve endings. 相似文献
93.
Jing Cheng Tamar Ringel-Kulka Ineke Heikamp-de Jong Yehuda Ringel Ian Carroll Willem M de Vos Jarkko Saloj?rvi Reetta Satokari 《The ISME journal》2016,10(4):1002-1014
The colonization pattern of intestinal microbiota during childhood may impact health later in life, but children older than 1 year are poorly studied. We followed healthy children aged 1–4 years (n=28) for up to 12 months, during which a synbiotic intervention and occasional antibiotics intake occurred, and compared them with adults from the same region. Microbiota was quantified with the HITChip phylogenetic microarray and analyzed with linear mixed effects model and other statistical approaches. Synbiotic administration increased the stability of Actinobacteria and antibiotics decreased Clostridium cluster XIVa abundance. Bacterial diversity did not increase in 1- to 5-year-old children and remained significantly lower than in adults. Actinobacteria, Bacilli and Clostridium cluster IV retained child-like abundances, whereas some other groups were converting to adult-like profiles. Microbiota stability increased, with Bacteroidetes being the main contributor. The common core of microbiota in children increased with age from 18 to 25 highly abundant genus-level taxa, including several butyrate-producing organisms, and developed toward an adult-like composition. In conclusion, intestinal microbiota is not established before 5 years of age and diversity, core microbiota and different taxa are still developing toward adult-type configuration. Discordant development patterns of bacterial phyla may reflect physiological development steps in children. 相似文献
94.
David Fisman Eleni Patrozou Yehuda Carmeli Eli Perencevich Ashleigh R. Tuite Leonard A. Mermel the Geographical Variability of Bacteremia Study Group 《PloS one》2014,9(12)
ObjectiveInfections due to Gram-negative bacteria exhibit seasonal trends, with peak infection rates during warmer months. We hypothesized that the likelihood of a bloodstream infection due to Gram-negative bacteria increases with proximity to the equator. We tested this hypothesis and identified geographical, climatic and social factors associated with this variability.DesignWe established a network of 23 international centers in 22 cities. Setting: De-identified results of positive blood cultures from 2007–2011 and data sources for geographic, climatic and socioeconomic factors were assembled for each center.ParticipantsPatients at the 23 centers with positive blood cultures.ResultsThe mean fraction of bacteremia associated with Gram-negative bacteria was 48.4% (range 26.4% to 61.8%). Although not all sites displayed significant seasonality, the overall P-value for seasonal oscillation was significant (P<0.001). In univariate meta-regression models, temperature, latitude, latitude squared, longitude, per capita gross domestic product and percent of gross domestic product spent on healthcare were all associated with the fraction of bacteremia due to Gram-negative bacteria. In multivariable models, only percent of gross domestic product spent on healthcare and distance from the equator (ie. latitude squared) were significantly associated with the fraction of bacteremia due to Gram-negative bacteria.ConclusionsThe likelihood of bacteremia due to Gram-negative bacteria varies markedly between cities, in a manner that appears to have both geographic (latitude) and socioeconomic (proportion gross domestic product devoted to health spending) determinants. Thus, the optimal approach to initial management of suspected bacteremia may be geographically specific. The rapid emergence of highly antibiotic-resistant Gram-negative pathogens may have geographically specific impacts. 相似文献
95.
Sinularia leptoclados (Ehrenberg, 1834) is re-described. Sinularia leptoclados var. gonatodes Kolonko, 1926 is synonymized with Sinularia maxima Verseveldt, 1977. Two new species of Sinularia with digitiform lobules, leptoclados-type surface clubs and unbranched interior spindles, are described. An updated maximum likelihood tree of Sinularia species with leptoclados-type clubs (clade 5C) based on two mitochondrial genes (mtMutS, COI) and a nuclear gene (28S rDNA) is presented. 相似文献
96.
Gill bacterial communities of Chama pacifica, an Indo-Pacific invasive oyster to the eastern Mediterranean Sea, were compared with those of Chama savignyi, its northern Red Sea congeneric species. Summer and winter bacterial populations were characterized and compared using 16S rDNA clone libraries, and seasonal population dynamics were monitored by automated ribosomal intergenic spacer analysis (ARISA). Clone libraries revealed a specific clade of bacteria, closely related to marine endosymbionts from the Indo-Pacific, found in both ecosystems, of which one taxon was conserved in oysters from both sites. This taxon was dominant in summer libraries and was weakly present in winter ones, where other members of this group were dominant. ARISA results revealed significant seasonal variation in bacterial populations of Mediterranean Sea oysters, as opposed to Red Sea ones that were stable throughout the year. We suggest that this conserved association between bacteria and oyster reflects either a symbiosis between the oyster host and some of its bacteria, a co-invasion of both parties, or both. 相似文献
97.
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99.
Most sexually reproducing animal species are characterized by two morphologically and behaviorally distinct sexes. The genetic, molecular and cellular processes that produce sexual dimorphisms are phylogenetically diverse, though in most cases they are thought to occur early in development. In some species, however, sexual dimorphisms are manifested after development is complete, suggesting the intriguing hypothesis that sex, more generally, might be considered a continuous trait that is influenced by both developmental and postdevelopmental processes. Here, we explore how biological sex is defined at the genetic, neuronal and behavioral levels, its effects on neuronal development and function, and how it might lead to sexually dimorphic behavioral traits in health and disease. We also propose a unifying framework for understanding neuronal and behavioral sexual dimorphisms in the context of both developmental and postdevelopmental, physiological timescales. Together, these two temporally separate processes might drive sex‐specific neuronal functions in sexually mature adults, particularly as it pertains to behavior in health and disease. 相似文献
100.
Ayelet Zauberman Yehuda Flashner Yinon Levy Yaron Vagima Avital Tidhar Ofer Cohen Erez Bar-Haim David Gur Moshe Aftalion Gideon Halperin Avigdor Shafferman Emanuelle Mamroud 《PloS one》2013,8(12)
Plague, initiated by Yersinia pestis infection, is a rapidly progressing disease with a high mortality rate if not quickly treated. The existence of antibiotic-resistant Y. pestis strains emphasizes the need for the development of novel countermeasures against plague. We previously reported the generation of a recombinant Y. pestis strain (Kim53ΔJ+P) that over-expresses Y. enterocolitica YopP. When this strain was administered subcutaneously to mice, it elicited a fast and effective protective immune response in models of bubonic, pneumonic and septicemic plague. In the present study, we further characterized the immune response induced by the Kim53ΔJ+P recombinant strain. Using a panel of mouse strains defective in specific immune functions, we observed the induction of a prompt protective innate immune response that was interferon-γ dependent. Moreover, inoculation of mice with Y. pestis Kim53ΔJ+P elicited a rapid protective response against secondary infection by other bacterial pathogens, including the enteropathogen Y. enterocolitica and the respiratory pathogen Francisella tularensis. Thus, the development of new therapies to enhance the innate immune response may provide an initial critical delay in disease progression following the exposure to highly virulent bacterial pathogens, extending the time window for successful treatment. 相似文献