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排序方式: 共有208条查询结果,搜索用时 15 毫秒
191.
Anne Schwerk Fabiana D. S. Alves Petra J. W. Pouwels Therese van Amelsvoort 《Journal of neurochemistry》2014,128(1):1-87
By reviewing the existing 1H‐magnetic resonance spectroscopy literature in schizophrenia, the relationship of different sample characteristics and applied methodologies with metabolite alterations is explored. Furthermore, we emphasize common pitfalls and discrepancies in the methodological framework of the reviewed studies that introduce unwanted variation in findings and complicate the comparison of studies. A total of 92 studies were reviewed. Articles were retrieved by searching the Pubmed database. Care was taken to note down reliability and validity measures of each included study. Despite many methodological differences and shortcomings, progressive NAA reductions could be seen in several brain regions implicated in the pathogenesis of schizophrenia. In terms of treatment effects, cross‐sectional evidence implicates a normalizing role for atypical antipsychotic medication; however, longitudinal studies remain inconclusive on this issue. Choline, creatine, and myo‐inositol levels remain largely unchanged and a time‐dependent role of glutamate finds confirmation in several spectroscopy studies. Other findings are less consistent and need further replication. Most studies lack power and methodological precision. Future studies should aim for standardization and for more distinguished study populations to gain more valid and reliable findings. 相似文献
192.
Romano I Lama L Nicolaus B Poli A Gambacorta A Giordano A 《The Journal of General and Applied Microbiology》2006,52(6):339-348
A halotolerant and alkaliphilic Gram-negative bacterium, strain 18bAG(T), that grows aerobically at the optimum temperature of 37 degrees C, and at pH 7.5-10 (optimum 9.0), was isolated from a salt pool located in Montefredane in Campania Region (South of Italy). The isolate tolerated high concentration of NaCl up to 20%. Strain 18bAG(T) accumulated osmolytes and polyhydroxybutyrate, produced exopolysaccharide and possessed alpha-glucosidase activity. The predominant respiratory quinones were ubiquinones, Q8 and Q6(6H); phosphoethanolamine, phosphatidylglycerol and diphosphatidylglycerol were the predominant polar lipids. Major fatty acids were C16 : 1, C16 : 0, and C18 : 0. On the basis of 16S rRNA gene sequence similarity, 18bAG(T) was shown to belong to Halomonas genus. Analysis of 16S rRNA gene revealed a high similarity of strain 18bAG(T) to Halomonas venusta (DSM 4743(T)) and Halomonas hydrothermalis (DSM 15725(T)). Level of DNA-DNA relatedness between strain 18bAG(T) and the most related species Halomonas venusta and Halomonas hydrothermalis was 56.0% and 41.2%, respectively. The G+C content (mol%) of DNA was 53.0. The RiboPrinting patterns of Halomonas venusta and 18AG(T) showed a pattern similarity of 0.50. On the basis of genomic information and phenotypic characteristics strain 18bAG(T) represents a new species, for which the name Halomonas alkaliphila sp. nov. is proposed. The type strain is 18bAG(T) (=DSM 16354T =ATCC BAA-953T). 相似文献
193.
B. Nicolaus V. Lanzotti A. Trincone M. De Rosa W.D. Grant A. Gambacorta 《FEMS microbiology letters》1989,59(1-2):157-160
Abstract Examples of halophilic archaebacteria contain low levels of between 1 and 20 mM trimethyl glycine (glycine betaine). In disrupted cell preparations, the glycine betaine is associated with the membrane fraction and is not detectable in cell supernatants. Cells of Natronococcus occultus grown in different salt concentrations show an increase in cell-associated glycine betaine along with an increase in the ratio of phosphatidyl glycerophosphate (PG) to phosphatidyl glycerol (PG) in the cell membrane. 相似文献
194.
Inês BoalCarvalho Bryl MazelSanchez Filo Silva Laure Garnier Soner Yildiz Joao PPL Bonifacio Chengyue Niu Nathalia Williams Patrice Francois Nicolaus Schwerk Jennifer Schning Julia Carlens Dorothee Viemann Stephanie Hugues Mirco Schmolke 《EMBO reports》2020,21(12)
Pyroptosis is a fulminant form of macrophage cell death, contributing to release of pro‐inflammatory cytokines. In humans, it depends on caspase 1/4‐activation of gasdermin D and is characterized by the release of cytoplasmic content. Pathogens apply strategies to avoid or antagonize this host response. We demonstrate here that a small accessory protein (PB1‐F2) of contemporary H5N1 and H3N2 influenza A viruses (IAV) curtails fulminant cell death of infected human macrophages. Infection of macrophages with a PB1‐F2‐deficient mutant of a contemporary IAV resulted in higher levels of caspase‐1 activation, cleavage of gasdermin D, and release of LDH and IL‐1β. Mechanistically, PB1‐F2 limits transition of NLRP3 from its auto‐repressed and closed confirmation into its active state. Consequently, interaction of a recently identified licensing kinase NEK7 with NLRP3 is diminished, which is required to initiate inflammasome assembly. 相似文献
195.
B Nicolaus L Lama E Esposito M C Manca R Improta M R Bellitti A W Duckworth W D Grant A Gambacorta 《Journal of industrial microbiology & biotechnology》1999,23(6):489-496
Three halobacteria strains (T5, T6, T7), growing optimally at a sodium chloride concentration of 3.5 M, were isolated from
samples collected in the Tunisian marine saltern located close to Monastir. Although they were different in colony and cell
morphology, the isolates were similar in most respects and all produced a homopolyester identified spectroscopically as polyhydroxybutyrate
when grown on carbohydrates. Under the same conditions, the isolates formed acidic exopolysaccharides. Acid methanolysis of
their complex lipids released archaeol (2,3-di-O-phytanyl-sn-glycerol). All the isolates had polar lipid patterns characteristic of representatives of the genus Haloarcula. Partial sequence analysis of 16S rRNA genes from strain T5 confirmed its assignment to the genus Haloarcula. Although strain T5 differed phenotypically from the species Haloarcula japonica in several respects, DNA–DNA hybridization indicated that the T5 isolate is a new strain of H. japonica.
Received 10 June 1998/ Accepted in revised form 29 July 1999 相似文献
196.
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198.
Koosje P. Lamers Marion Nicolaus Eldar Rakhimberdiev Jan-Åke Nilsson Christiaan Both 《Journal of avian biology》2020,51(2)
In polygynous species with biparental care, mates are often acquired in succession. Most research has focussed on the cost of polygyny in secondary females, but primary females may also suffer from reduced paternal care. The likelihood of sharing a male may be higher for early laying females, which could counteract the fitness benefits of breeding early. In this study, we use 12 years of data on pied flycatchers Ficedula hypoleuca, to show that the likelihood of becoming a primary female of a polygynous male declines over the season. Moreover, we provide experimental evidence that early breeding elevates polygyny risk, through an experimental manipulation that introduced early breeding females to a population with later breeding phenology. We found that, independently of breeding date, primary females slightly more often experienced complete brood failures than monogamous females, but did not differ in number of fledged offspring among successful broods or number of locally returning recruits. However, apparent survival in subsequent years was substantially lower in primary females, indicating that they may compensate for reduced male care at the expense of future reproduction. Our study reveals that polygyny risk indeed increases with early breeding and entails a local survival cost for primary females. However, this cost is likely largely outweighed by fitness benefits of early breeding in most years. Hence it is unlikely that the increased polygyny risk of early breeding counteracts the fitness benefits, but it may reduce selection for breeding extremely early. 相似文献
199.
Complex organs such as the eyes of vertebrates are based upon highly polygenic systems. So, remarkable differences in the eyes of cave fishes and their overground ancestors are caused by several mutations. Although in cavernicolous populations natural selection seems to play no part in eye degeneration, there is evidence for morphologic regularities in the degenerative process. These morphologic regularities are due to pleiotropic effects of the mutating genes. 相似文献
200.
Marion Nicolaus Céline Le Bohec Paul M. Nolan Michel Gauthier-Clerc Yvon Le Maho Jan Komdeur Pierre Jouventin 《Polar Biology》2007,31(1):53-61
We investigated whether delayed plumage maturation occurred in king penguins (Aptenodytes patagonicus). Therefore we examined the relationships between age and sex on spectral properties and size of two colored plumage patches
and a UV-reflective beak spot, using known-age cohorts. Unlike the colored patch on the breast, we found age differences in
ear and beak coloration. These results suggest that head ornaments in king penguins could signal sexual maturity or social
status. No sex differences were found in the intensity of colored ornaments, which can result from mutual mate choice or genetic
correlation between sexes. Size of colored patches did not relate to age or sex. 相似文献