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排序方式: 共有343条查询结果,搜索用时 11 毫秒
281.
Adam?SanMiguel Elizabeth?A.?GriceEmail author 《Cellular and molecular life sciences : CMLS》2015,72(8):1499-1515
The skin is colonized by an assemblage of microorganisms which, for the most part, peacefully coexist with their hosts. In some cases, these communities also provide vital functions to cutaneous health through the modulation of host factors. Recent studies have illuminated the role of anatomical skin site, gender, age, and the immune system in shaping the cutaneous ecosystem. Alterations to microbial communities have also been associated with, and likely contribute to, a number of cutaneous disorders. This review focuses on the host factors that shape and maintain skin microbial communities, and the reciprocal role of microbes in modulating skin immunity. A greater understanding of these interactions is critical to elucidating the forces that shape cutaneous populations and their contributions to skin homeostasis. This knowledge can also inform the tendency of perturbations to predispose and/or bring about certain skin disorders. 相似文献
282.
Gudmundsson J Sulem P Manolescu A Amundadottir LT Gudbjartsson D Helgason A Rafnar T Bergthorsson JT Agnarsson BA Baker A Sigurdsson A Benediktsdottir KR Jakobsdottir M Xu J Blondal T Kostic J Sun J Ghosh S Stacey SN Mouy M Saemundsdottir J Backman VM Kristjansson K Tres A Partin AW Albers-Akkers MT Godino-Ivan Marcos J Walsh PC Swinkels DW Navarrete S Isaacs SD Aben KK Graif T Cashy J Ruiz-Echarri M Wiley KE Suarez BK Witjes JA Frigge M Ober C Jonsson E Einarsson GV Mayordomo JI Kiemeney LA 《Nature genetics》2007,39(5):631-637
Prostate cancer is the most prevalent noncutaneous cancer in males in developed regions, with African American men having among the highest worldwide incidence and mortality rates. Here we report a second genetic variant in the 8q24 region that, in conjunction with another variant we recently discovered, accounts for about 11%-13% of prostate cancer cases in individuals of European descent and 31% of cases in African Americans. We made the current discovery through a genome-wide association scan of 1,453 affected Icelandic individuals and 3,064 controls using the Illumina HumanHap300 BeadChip followed by four replication studies. A key step in the discovery was the construction of a 14-SNP haplotype that efficiently tags a relatively uncommon (2%-4%) susceptibility variant in individuals of European descent that happens to be very common (approximately 42%) in African Americans. The newly identified variant shows a stronger association with affected individuals who have an earlier age at diagnosis. 相似文献
283.
Peacock CS Seeger K Harris D Murphy L Ruiz JC Quail MA Peters N Adlem E Tivey A Aslett M Kerhornou A Ivens A Fraser A Rajandream MA Carver T Norbertczak H Chillingworth T Hance Z Jagels K Moule S Ormond D Rutter S Squares R Whitehead S Rabbinowitsch E Arrowsmith C White B Thurston S Bringaud F Baldauf SL Faulconbridge A Jeffares D Depledge DP Oyola SO Hilley JD Brito LO Tosi LR Barrell B Cruz AK Mottram JC Smith DF Berriman M 《Nature genetics》2007,39(7):839-847
Leishmania parasites cause a broad spectrum of clinical disease. Here we report the sequencing of the genomes of two species of Leishmania: Leishmania infantum and Leishmania braziliensis. The comparison of these sequences with the published genome of Leishmania major reveals marked conservation of synteny and identifies only approximately 200 genes with a differential distribution between the three species. L. braziliensis, contrary to Leishmania species examined so far, possesses components of a putative RNA-mediated interference pathway, telomere-associated transposable elements and spliced leader-associated SLACS retrotransposons. We show that pseudogene formation and gene loss are the principal forces shaping the different genomes. Genes that are differentially distributed between the species encode proteins implicated in host-pathogen interactions and parasite survival in the macrophage. 相似文献
284.
Sebaihia M Wren BW Mullany P Fairweather NF Minton N Stabler R Thomson NR Roberts AP Cerdeño-Tárraga AM Wang H Holden MT Wright A Churcher C Quail MA Baker S Bason N Brooks K Chillingworth T Cronin A Davis P Dowd L Fraser A Feltwell T Hance Z Holroyd S Jagels K Moule S Mungall K Price C Rabbinowitsch E Sharp S Simmonds M Stevens K Unwin L Whithead S Dupuy B Dougan G Barrell B Parkhill J 《Nature genetics》2006,38(7):779-786
We determined the complete genome sequence of Clostridium difficile strain 630, a virulent and multidrug-resistant strain. Our analysis indicates that a large proportion (11%) of the genome consists of mobile genetic elements, mainly in the form of conjugative transposons. These mobile elements are putatively responsible for the acquisition by C. difficile of an extensive array of genes involved in antimicrobial resistance, virulence, host interaction and the production of surface structures. The metabolic capabilities encoded in the genome show multiple adaptations for survival and growth within the gut environment. The extreme genome variability was confirmed by whole-genome microarray analysis; it may reflect the organism's niche in the gut and should provide information on the evolution of virulence in this organism. 相似文献
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287.
Zhou Z Feng H Zhou BR Ghirlando R Hu K Zwolak A Miller Jenkins LM Xiao H Tjandra N Wu C Bai Y 《Nature》2011,472(7342):234-237
The centromere is a unique chromosomal locus that ensures accurate segregation of chromosomes during cell division by directing the assembly of a multiprotein complex, the kinetochore. The centromere is marked by a conserved variant of conventional histone H3 termed CenH3 or CENP-A (ref. 2). A conserved motif of CenH3, the CATD, defined by loop 1 and helix 2 of the histone fold, is necessary and sufficient for specifying centromere functions of CenH3 (refs 3, 4). The structural basis of this specification is of particular interest. Yeast Scm3 and human HJURP are conserved non-histone proteins that interact physically with the (CenH3-H4)(2) heterotetramer and are required for the deposition of CenH3 at centromeres in vivo. Here we have elucidated the structural basis for recognition of budding yeast (Saccharomyces cerevisiae) CenH3 (called Cse4) by Scm3. We solved the structure of the Cse4-binding domain (CBD) of Scm3 in complex with Cse4 and H4 in a single chain model. An α-helix and an irregular loop at the conserved amino terminus and a shorter α-helix at the carboxy terminus of Scm3(CBD) wraps around the Cse4-H4 dimer. Four Cse4-specific residues in the N-terminal region of helix 2 are sufficient for specific recognition by conserved and functionally important residues in the N-terminal helix of Scm3 through formation of a hydrophobic cluster. Scm3(CBD) induces major conformational changes and sterically occludes DNA-binding sites in the structure of Cse4 and H4. These findings have implications for the assembly and architecture of the centromeric nucleosome. 相似文献
288.
Potential impacts of a warming climate on water availability in snow-dominated regions 总被引:25,自引:0,他引:25
All currently available climate models predict a near-surface warming trend under the influence of rising levels of greenhouse gases in the atmosphere. In addition to the direct effects on climate--for example, on the frequency of heatwaves--this increase in surface temperatures has important consequences for the hydrological cycle, particularly in regions where water supply is currently dominated by melting snow or ice. In a warmer world, less winter precipitation falls as snow and the melting of winter snow occurs earlier in spring. Even without any changes in precipitation intensity, both of these effects lead to a shift in peak river runoff to winter and early spring, away from summer and autumn when demand is highest. Where storage capacities are not sufficient, much of the winter runoff will immediately be lost to the oceans. With more than one-sixth of the Earth's population relying on glaciers and seasonal snow packs for their water supply, the consequences of these hydrological changes for future water availability--predicted with high confidence and already diagnosed in some regions--are likely to be severe. 相似文献
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290.
1 Results Intermittent Contact Mode Atomic Force Microscopy (ICM-AFM) imaging of sub-micron morphology is a routine operation in many fields of research from materials science to molecular biology,typically used to obtain three dimensional geometrical measures of surface structures.When it comes to the nanometer-angstrom range,however,quantitative interpretation of AFM morphology is less straightforward.Reports of non-topography-originated features as well as anomalies and conflicting reports in nanostr... 相似文献