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81.
Cronobacter has caused numerous illnesses in neonates, infants, and children. Here we report the draft genome of Cronobacter sakazakii E899. Whole-genome sequence analysis of Cronobacter strains provides a tool for understanding the genomic regions specific to each individual species. 相似文献
82.
Short interspersed nuclear elements (SINEs) are a type of class 1 transposable element (retrotransposon) with features that allow investigators to resolve evolutionary relationships between populations and species while providing insight into genome composition and function. Characterization of a Carnivora-specific SINE family, Can-SINEs, has, has aided comparative genomic studies by providing rare genomic changes, and neutral sequence variants often needed to resolve difficult evolutionary questions. In addition, Can-SINEs constitute a significant source of functional diversity with Carnivora. Publication of the whole-genome sequence of domestic dog, domestic cat, and giant panda serves as a valuable resource in comparative genomic inferences gleaned from Can-SINEs. In anticipation of forthcoming studies bolstered by new genomic data, this review describes the discovery and characterization of Can-SINE motifs as well as describes composition, distribution, and effect on genome function. As the contribution of noncoding sequences to genomic diversity becomes more apparent, SINEs and other transposable elements will play an increasingly large role in mammalian comparative genomics. 相似文献
83.
Magaly Toro Guojie Cao Wenting Ju Marc Allard Rodolphe Barrangou Shaohua Zhao Eric Brown Jianghong Meng 《Applied and environmental microbiology》2014,80(4):1411-1420
Shiga toxin-producing Escherichia coli (STEC) strains (n = 194) representing 43 serotypes and E. coli K-12 were examined for clustered regularly interspaced short palindromic repeat (CRISPR) arrays to study genetic relatedness among STEC serotypes. A subset of the strains (n = 81) was further analyzed for subtype I-E cas and virulence genes to determine a possible association of CRISPR elements with potential virulence. Four types of CRISPR arrays were identified. CRISPR1 and CRISPR2 were present in all strains tested; 1 strain also had both CRISPR3 and CRISPR4, whereas 193 strains displayed a short, combined array, CRISPR3-4. A total of 3,353 spacers were identified, representing 528 distinct spacers. The average length of a spacer was 32 bp. Approximately one-half of the spacers (54%) were unique and found mostly in strains of less common serotypes. Overall, CRISPR spacer contents correlated well with STEC serotypes, and identical arrays were shared between strains with the same H type (O26:H11, O103:H11, and O111:H11). There was no association identified between the presence of subtype I-E cas and virulence genes, but the total number of spacers had a negative correlation with potential pathogenicity (P < 0.05). Fewer spacers were found in strains that had a greater probability of causing outbreaks and disease than in those with lower virulence potential (P < 0.05). The relationship between the CRISPR-cas system and potential virulence needs to be determined on a broader scale, and the biological link will need to be established. 相似文献
84.
Jantien van Berkel Cécile R. L. Boot Karin I. Proper Paulien M. Bongers Allard J. van der Beek 《PloS one》2014,9(1)
Objectives
The aim of the present study was to evaluate the effectiveness of a worksite mindfulness-related multi-component health promotion intervention on work engagement, mental health, need for recovery and mindfulness.Methods
In a randomized controlled trial design, 257 workers of two research institutes participated. The intervention group (n = 129) received a targeted mindfulness-related training, followed by e-coaching. The total duration of the intervention was 6 months. Data on work engagement, mental health, need for recovery and mindfulness were collected using questionnaires at baseline and after 6 and 12 months follow-up. Effects were analyzed using linear mixed effect models.Results
There were no significant differences in work engagement, mental health, need for recovery and mindfulness between the intervention and control group after either 6- or 12-months follow-up. Additional analyses in mindfulness-related training compliance subgroups (high and low compliance versus the control group as a reference) and subgroups based on baseline work engagement scores showed no significant differences either.Conclusions
This study did not show an effect of this worksite mindfulness-related multi-component health promotion intervention on work engagement, mental health, need for recovery and mindfulness after 6 and 12 months.Trial registration
Netherlands Trial Register NTR2199 相似文献85.
Charlotte Bernard Bixente Dilharreguy Michèle Allard Hélène Amieva Fabrice Bonnet Frédéric Dauchy Carinne Greib Patrick Dehail Gwéna?lle Catheline for the ANRS CO Aquitaine cohort study group 《PloS one》2013,8(7)
Motor impairment is highly prevalent in HIV-infected patients. Here, we assess associations between peripheral muscular deficits as evaluated by the 5 sit-to-stand test (5STS) and structural integrity of the motor system at a central level. Eighty-six HIV-infected patients receiving combination antiretroviral therapy and with no major cerebral events, underwent an MRI scan and the 5STS. Out of 86 participants, forty presented a score greater than two standard deviations above mean normative scores calculated for the 5STS and were therefore considered as motor-impaired. MRI-structural cerebral parameters were compared to the unimpaired participants. Fractional Anisotropy (FA), Axial Diffusivity (AD) and Radial Diffusivity (RD), reflecting microstructural integrity, were extracted from Diffusion-Tensor MRI. Global and regional cerebral volumes or thicknesses were extracted from 3D-T1 morphological MRI. Whereas the two groups did not differ for any HIV variables, voxel-wise analysis revealed that motor-impaired participants present low FA values in various cortico-motor tracts and low AD in left cortico-spinal tract. However, they did not present reduced volumes or thicknesses of the precentral cortices compared to unimpaired participants. The absence of alterations in cortical regions holding motor-neurons might argue against neurodegenerative process as an explanation of White Matter (WM) disorganization. 相似文献
86.
Jo Oldknow Tanya M. Franklin Martin Trick Sharon Allard Laurian S. Robert 《Sexual plant reproduction》1995,8(4):254-255
The DNA sequence data reported have been lodged in the Genbank, EMBL and DDBJ databases under the accession numbers Z21609 and Z26914 相似文献
87.
Weiwei Luo Cheng-han Yu Zi Zhao Lieu Jun Allard Alex Mogilner Michael P. Sheetz Alexander D. Bershadsky 《The Journal of cell biology》2013,202(7):1057-1073
A ctin filaments, with the aid of multiple accessory proteins, self-assemble into a variety of network patterns. We studied the organization and dynamics of the actin network in nonadhesive regions of cells bridging fibronectin-coated adhesive strips. The network was formed by actin nodes associated with and linked by myosin II and containing the formin disheveled-associated activator of morphogenesis 1 (DAAM1) and the cross-linker filamin A (FlnA). After Latrunculin A (LatA) addition, actin nodes appeared to be more prominent and demonstrated drift-diffusion motion. Superresolution microscopy revealed that, in untreated cells, DAAM1 formed patches with a similar spatial arrangement to the actin nodes. Node movement (diffusion coefficient and velocity) in LatA-treated cells was dependent on the level and activity of myosin IIA, DAAM1, and FlnA. Based on our results, we developed a computational model of the dynamic formin-filamin-actin asters that can self-organize into a contractile actomyosin network. We suggest that such networks are critical for connecting distant parts of the cell to maintain the mechanical coherence of the cytoplasm. 相似文献
88.
Pairwise linkage disequilibrium values (D) were estimated for 14 allozyme loci in two natural populations of lodgepole pine (Pinus contorta ssp. latifolia). Maternal multilocus genotypes were inferred from samples of (haploid) megagametophytic seed-endosperms. Coupling/repulsion double heterozygotes were distinguished for closely linked pairs of loci. Assays of seven of the loci in seed embryos allowed estimates of D for these loci in the outcross pollen pool (estimates of outcrossing rates indicate no significant departures from random mating in either population). No disequilibrium was observed between unlinked loci in either maternal genotypes or outcross pollen. However, significant disequilibrium was observed within and between gametes for some allelic combinations of four tightly linked loci; the assumption of random association of gamete types within individuals is thus invalid for some loci in lodgepole pine. Possible causes of the observed D were examined using the noncentrality parameter of the general noncentral chi square distribution. We concluded, from estimates of population size, linkage and measurements of population substructure, that neither drift nor population subdivision was responsible for the significant values of D which were observed and that epistatic selection was the most likely cause of the disequilibrium observed. 相似文献
89.
Ghosh S Kewalramani G Yuen G Pulinilkunnil T An D Innis SM Allard MF Wambolt RB Qi D Abrahani A Rodrigues B 《Free radical biology & medicine》2006,41(9):1413-1424
Increased awareness of obesity has led to a dietary shift toward "heart-friendly" vegetable oils containing omega-6 polyunsaturated fatty acid (omega-6 PUFA). In addition to its beneficial effects, omega-6 PUFA also exhibits proinflammatory and prooxidative properties. We hypothesized that chronic dietary omega-6 PUFA can induce free radical generation, predisposing the cardiac mitochondria to oxidative damage. Male Wistar rats were fed a diet supplemented with 20% w/w sunflower oil, rich in omega-6 PUFA (HP) or normal laboratory chow (LP) for 4 weeks. HP feeding augmented phospholipase A(2) activity and breakdown of cardiolipin, a mitochondrial phospholipid. HP hearts also demonstrated elevated inducible nitric oxide synthase expression, loss of Mn superoxide dismutase, and increased mitochondrial nitrotyrosine levels. In these hearts, oxidative damage to mitochondrial DNA (mDNA) was demonstrated by 8-hydroxyguanosine immunopositivity, overexpression of DNA repair enzymes, and a decrease in the mRNA expression of specific respiratory subunits encoded by the mDNA. Functionally, at higher workloads, HP hearts also demonstrated a greater decline in cardiac work than LP, suggesting a compromised mitochondrial reserve. Our study, for the first time, demonstrates that consumption of a high fat diet rich in omega-6 PUFA for only 4 weeks instigates mitochondrial nitrosative damage and causes cardiac dysfunction at high afterloads. 相似文献
90.
Kvin Cilleros Alice Valentini Luc Allard Tony Dejean Roselyne Etienne Gaël Grenouillet Amaia Iribar Pierre Taberlet Rgis Vigouroux Sbastien Brosse 《Molecular ecology resources》2019,19(1):27-46
Determining the species compositions of local assemblages is a prerequisite to understanding how anthropogenic disturbances affect biodiversity. However, biodiversity measurements often remain incomplete due to the limited efficiency of sampling methods. This is particularly true in freshwater tropical environments that host rich fish assemblages, for which assessments are uncertain and often rely on destructive methods. Developing an efficient and nondestructive method to assess biodiversity in tropical freshwaters is highly important. In this study, we tested the efficiency of environmental DNA (eDNA) metabarcoding to assess the fish diversity of 39 Guianese sites. We compared the diversity and composition of assemblages obtained using traditional and metabarcoding methods. More than 7,000 individual fish belonging to 203 Guianese fish species were collected by traditional sampling methods, and ~17 million reads were produced by metabarcoding, among which ~8 million reads were assigned to 148 fish taxonomic units, including 132 fish species. The two methods detected a similar number of species at each site, but the species identities partially matched. The assemblage compositions from the different drainage basins were better discriminated using metabarcoding, revealing that while traditional methods provide a more complete but spatially limited inventory of fish assemblages, metabarcoding provides a more partial but spatially extensive inventory. eDNA metabarcoding can therefore be used for rapid and large‐scale biodiversity assessments, while at a local scale, the two approaches are complementary and enable an understanding of realistic fish biodiversity. 相似文献