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51.
Peter Vandamme Edward R.B. Moore Margo Cnockaert Charlotte Peeters Liselott Svensson-Stadler Kurt Houf Theodore Spilker John J. LiPuma 《Systematic and applied microbiology》2013
The phenotypic and genotypic characteristics of seventeen Achromobacter strains representing MLST genogroups 2, 5, 7 and 14 were examined. Although genogroup 2 and 14 strains shared a DNA–DNA hybridization level of about 70%, the type strains of both genogroups differed in numerous biochemical characteristics and all genogroup 2 and 14 strains could by distinguished by nitrite reduction, denitrification and growth on acetamide. Given the MLST sequence divergence which identified genogroups 2 and 14 as clearly distinct populations, the availability of nrdA sequence analysis as a single locus identification tool for all Achromobacter species and genogroups, and the differential phenotypic characteristics, we propose to formally classify Achromobacter genogroups 2, 5, 7 and 14 as four novel Achromobacter species for which we propose the names Achromobacter insuavis sp. nov. (with strain LMG 26845T [= CCUG 62426T] as the type strain), Achromobacter aegrifaciens sp. nov. (with strain LMG 26852T [= CCUG 62438T] as the type strain), Achromobacter anxifer sp. nov. (with strain LMG 26857T [= CCUG 62444T] as the type strain), and Achromobacter dolens sp. nov. (with strain LMG 26840T [= CCUG 62421T] as the type strain). 相似文献
52.
Use of RNAlater® as a preservation method for parasitic coprology studies in wild-living chimpanzees
P. Drakulovski S. Locatelli C. Butel S. Pion D. Krasteva E. Mougdi-Pole E. Delaporte M. Peeters M. Mallié 《Experimental parasitology》2013
We evaluated the use of an RNA stabilisation buffer, RNAlater® (Ambion, Austin, Texas), as a preservation medium for parasitic coprology analysis of faecal samples collected from chimpanzees living in the wild (Pan troglodytes troglodytes). Thirty faecal samples collected in the forests of south-east Cameroon (Mambele area) from 2003 to 2011 were preserved in RNAlater® at −80 °C and analysed for their parasite content. We identified and counted parasitic elements and assessed their shape, size and morphology in relation to the storage time of the samples. We found that parasite elements were identifiable in RNAlater® preserved samples after as many as 7 years, showing that RNAlater® could be an effective and reliable preservation medium for coprology. Thus, its use could be an interesting way to optimise sample collection for several types of studies (parasitology and bacteriology/virology) at once, especially considering the logistically challenging and time-consuming field campaigns needed to obtain these faecal samples. 相似文献
53.
Ants have distinct morphological castes (queens and workers), but aberrant queen-worker “intercastes” occasionally occur, both in wild and laboratory conditions. Intercastes are rare, however, such novel phenotypes may have evolutionary significance. Their morphology is highly variable in any given species, providing valuable information about the integration of queen traits (e.g. ocelli, wings, complex segmentation of thorax, large gaster and ovaries, spermatheca). Generally, these traits are all diminished or absent in workers. We used multivariate morphometry to analyze an exceptionally large sample of 101 intercastes of Temnothorax nylanderi. We determined distributions and correlations of traits, and confirmed the mosaic nature of intercastes. Queen-specific traits are not expressed coherently in intercastes, but the possible patterns of trait combination are limited. A large number of small-sized intercastes had disproportionately larger head, ocelli and gaster but smaller thorax. In contrast, queen-like growth of thorax and rudimentary wings only occurred in large-sized intercastes. This is the most comprehensive analysis of intercaste variability, and suggests the existence of constraints on recombination of caste-specific modular traits. 相似文献
54.
55.
Jérémy Jabiol Andreas Bruder Mark O. Gessner Marika Makkonen Brendan G. McKie Edwin T.H.M. Peeters Veronique C.A. Vos Eric Chauvet 《Fungal Ecology》2013,6(5):439-448
Information about the global distribution of aquatic hyphomycetes is scarce, despite the primary importance of these fungi in stream ecosystem functioning. In particular, the relationship between their diversity and latitude remains unclear, due to a lack of coordinated surveys across broad latitudinal ranges. This study is a first report on latitudinal patterns of aquatic hyphomycete diversity associated with native leaf-litter species in five streams located along a gradient extending from the subarctic to the tropics. Exposure of leaf litter in mesh bags of three different mesh sizes facilitated assessing the effects of including or excluding different size-classes of litter-consuming invertebrates. Aquatic hyphomycete evenness was notably constant across all sites, whereas species richness and diversity, expressed as the Hill number, reached a maximum at mid-latitudes (Mediterranean and temperate streams). These latitudinal patterns were consistent across litter species, despite a notable influence of litter identity on fungal communities at the local scale. As a result, the bell-shaped distribution of species richness and Hill diversity deviated markedly from the latitudinal patterns of most other groups of organisms. Differences in the body-size distribution of invertebrate communities colonizing the leaves had no effect on aquatic hyphomycete species richness, Hill diversity or evenness, but invertebrates could still influence fungal communities by depleting litter, an effect that was not captured by the design of our experiment. 相似文献
56.
Evelien van der Meij Giel G. Koning Patrick W. Vriens Marcel F. Peeters C. Arnoud Meijer Kim E. Kortekaas Ronald L. Dalman J. Hajo van Bockel Roeland Hanemaaijer Teake Kooistra Robert Kleemann Jan H. N. Lindeman 《PloS one》2013,8(1)
Statins are thought to reduce vascular inflammation through lipid independent mechanisms. Evaluation of such an effect in atherosclerotic disease is complicated by simultaneous effects on lipid metabolism. Abdominal aortic aneurysms (AAA) are part of the atherosclerotic spectrum of diseases. Unlike atherosclerotic occlusive disease, AAA is not lipid driven, thus allowing direct evaluation of putative anti-inflammatory effects. The anti-inflammatory potency of increasing doses (0, 20 or 40 mg/day) simvastatin or atorvastatin was evaluated in 63 patients that were at least 6 weeks on statin therapy and who underwent open AAA repair. A comprehensive analysis using immunohistochemistry, mRNA and protein analyses was applied on aortic wall samples collected during surgery. The effect of statins on AAA growth was analyzed in a separate prospective study in incorporating 142 patients. Both statins equally effectively and dose-dependently reduced aortic wall expression of NFκB regulated mediators (i.e. IL-6 (P<0.001) and MCP-1 (P<0.001)); shifted macrophage polarization towards a M2 phenotype (P<0.0003); selectively reduced macrophage-related markers such as cathepsin K and S (P<0.009 and 0.0027 respectively), and ALOX5 (P<0.0009), and reduced vascular wall NFκB activity (40 mg/day group, P<0.016). No effect was found on other cell types. Evaluation of the clinical efficacy of statins to reduce AAA progression did not indicate an effect of statins on aneurysm growth (P<0.337). Hence, in the context of AAA the clinical relevance of statins pleiotropy appears minimal. 相似文献
57.
Amorphous Cobalt Boride (Co2B) as a Highly Efficient Nonprecious Catalyst for Electrochemical Water Splitting: Oxygen and Hydrogen Evolution 下载免费PDF全文
58.
Elske T. Massolt Grigoris Effraimidis Tim I. M. Korevaar Wilmar M. Wiersinga W. Edward Visser Robin P. Peeters Hemmo A. Drexhage 《PloS one》2016,11(4)
BackgroundSubjects at risk for major mood disorders have a higher risk to develop autoimmune thyroid disease (AITD) and vice-versa, implying a shared pathogenesis. In mood disorder patients, an abnormal profile of hematopoietic/neuronal growth factors is observed, suggesting that growth/differentiation abnormalities of these cell lineages may predispose to mood disorders. The first objective of our study was to investigate whether an aberrant profile of these hematopoietic/neuronal growth factors is also detectable in subjects at risk for AITD. A second objective was to study the inter relationship of these factors with previously determined and published growth factors/cytokines in the same subjects.MethodsWe studied 64 TPO-Ab-negative females with at least 1 first- or second-degree relative with AITD, 32 of whom did and 32 who did not seroconvert to TPO-Ab positivity in 5-year follow-up. Subjects were compared with 32 healthy controls (HCs). We measured serum levels of brain-derived neurotrophic factor (BDNF), Stem Cell Factor (SCF), Insulin-like Growth Factor-Binding Protein 2 (IGFBP-2), Epidermal Growth Factor (EGF) and IL-7 at baseline.ResultsBDNF was significantly lower (8.2 vs 18.9 ng/ml, P<0.001), while EGF (506.9 vs 307.6 pg/ml, P = 0.003) and IGFBP-2 (388.3 vs 188.5 ng/ml, P = 0.028) were significantly higher in relatives than in HCs. Relatives who seroconverted in the next 5 years had significantly higher levels of SCF than non-seroconverters (26.5 vs 16.7 pg/ml, P = 0.017). In a cluster analysis with the previously published growth factors/cytokines SCF clustered together with IL-1β, IL-6 and CCL-3, of which high levels also preceded seroconversion.ConclusionRelatives of AITD patients show aberrant serum levels of 4 hematopoietic/neuronal growth factors similar to the aberrancies found in mood disorder patients, suggesting that shared growth and differentiation defects in both the hematopoietic and neuronal system may underlie thyroid autoimmunity and mood disorders. A distinct pattern of four inter correlating immune factors in the relatives preceded TPO-Ab seroconversion in the next 5 years. 相似文献
59.
Zan Strabac Toril Aalberg Anders Todal Jenssen Marko Valenta 《Ethnic and racial studies》2016,39(15):2665-2682
Immigrant women are a particularly vulnerable part of the immigrant population. In this paper we analyse negative attitudes towards immigrant women in Norway. We focus on immigrant women’s formal job qualifications, their religious background and wearing of hijab – the headscarf sometimes used by Muslim women. Using survey-embedded experiments we are able to analyse the net effects on attitudes of job qualifications, Islamic religious background and the hijab. The results show that native population frequently has more negative views of Muslim women who wear a hijab. The negative effects of a hijab do not seem to be strongly reduced if a woman wearing it has higher education. With a single exception, the results also show that Muslim background in itself (i.e. without the hijab) does not have any strong effect on attitudes of the native population towards immigrant women. 相似文献