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991.
Piškur B Bajc M Robek R Humar M Sinjur I Kadunc A Oven P Rep G Al Sayegh Petkovšek S Kraigher H Jurc D Pohleven F 《Bioresource technology》2011,102(22):10611-10617
The influence of Pleurotus ostreatus inoculation on wood degradation and on fungal community structure was studied. The experiments were performed on an organically poor fly ash deposit covered with a 10 cm layer of beech wood chips inoculated with P. ostreatus isolate ZIM76. Compared to non-inoculated wood chips, inoculation increased the temperatures and relative humidities and, in the first 6 months, accelerated Klason lignin degradation by 9% and also, after 17 months, increased iron translocation into wood chips by 30%. After 6 months, PCR-DGGE showed 22-28 and 13-21 fungal taxa in non-inoculated and P. ostreatus-inoculated beech chips, respectively. The differences in number of taxa and in the fungal community structure (based on Dice coefficient) between non-inoculated and inoculated wood chips diminished with time. The results indicate that the naturally occurring processes of wood degradation are as efficient as those occurring in sites inoculated with P. ostreatus. 相似文献
992.
Watterson SH Langevine CM Van Kirk K Kempson J Guo J Spergel SH Das J Moquin RV Dyckman AJ Nirschl D Gregor K Pattoli MA Yang X McIntyre KW Yang G Galella MA Booth-Lute H Chen L Yang Z Wang-Iverson D McKinnon M Dodd JH Barrish JC Burke JR Pitts WJ 《Bioorganic & medicinal chemistry letters》2011,21(23):7006-7012
The synthesis, structure-activity relationships (SAR), and biological results of pyridyl-substituted azaindole based tricyclic inhibitors of IKK2 are described. Compound 4m demonstrated potent in vitro potency, acceptable pharmacokinetic and physicochemical properties, and efficacy when dosed orally in a mouse model of inflammatory bowel disease. 相似文献
993.
Kocbek S Sætre R Stiglic G Kim JD Pernek I Tsuruoka Y Kokol P Ananiadou S Tsujii J 《Bioinformatics (Oxford, England)》2011,27(8):1185-1186
Often, the most informative genes have to be selected from different gene sets and several computer gene ranking algorithms have been developed to cope with the problem. To help researchers decide which algorithm to use, we developed the analysis of gene ranking algorithms (AGRA) system that offers a novel technique for comparing ranked lists of genes. The most important feature of AGRA is that no previous knowledge of gene ranking algorithms is needed for their comparison. Using the text mining system finding-associated concepts with text analysis. AGRA defines what we call biomedical concept space (BCS) for each gene list and offers a comparison of the gene lists in six different BCS categories. The uploaded gene lists can be compared using two different methods. In the first method, the overlap between each pair of two gene lists of BCSs is calculated. The second method offers a text field where a specific biomedical concept can be entered. AGRA searches for this concept in each gene lists' BCS, highlights the rank of the concept and offers a visual representation of concepts ranked above and below it. AVAILABILITY AND IMPLEMENTATION: Available at http://agra.fzv.uni-mb.si/, implemented in Java and running on the Glassfish server. CONTACT: simon.kocbek@uni-mb.si. 相似文献
994.
Identifying polyglutamine protein species in situ that best predict neurodegeneration 总被引:1,自引:0,他引:1
Miller J Arrasate M Brooks E Libeu CP Legleiter J Hatters D Curtis J Cheung K Krishnan P Mitra S Widjaja K Shaby BA Lotz GP Newhouse Y Mitchell EJ Osmand A Gray M Thulasiramin V Saudou F Segal M Yang XW Masliah E Thompson LM Muchowski PJ Weisgraber KH Finkbeiner S 《Nature chemical biology》2011,7(12):925-934
Polyglutamine (polyQ) stretches exceeding a threshold length confer a toxic function to proteins that contain them and cause at least nine neurological disorders. The basis for this toxicity threshold is unclear. Although polyQ expansions render proteins prone to aggregate into inclusion bodies, this may be a neuronal coping response to more toxic forms of polyQ. The exact structure of these more toxic forms is unknown. Here we show that the monoclonal antibody 3B5H10 recognizes a species of polyQ protein in situ that strongly predicts neuronal death. The epitope selectively appears among some of the many low-molecular-weight conformational states assumed by expanded polyQ and disappears in higher-molecular-weight aggregated forms, such as inclusion bodies. These results suggest that protein monomers and possibly small oligomers containing expanded polyQ stretches can adopt a conformation that is recognized by 3B5H10 and is toxic or closely related to a toxic species. 相似文献
995.
Microbiota restoration: natural and supplemented recovery of human microbial communities 总被引:1,自引:0,他引:1
Reid G Younes JA Van der Mei HC Gloor GB Knight R Busscher HJ 《Nature reviews. Microbiology》2011,9(1):27-38
In a healthy host, a balance exists between members of the microbiota, such that potential pathogenic and non-pathogenic organisms can be found in apparent harmony. During infection, this balance can become disturbed, leading to often dramatic changes in the composition of the microbiota. For most bacterial infections, nonspecific antibiotics are used, killing the non-pathogenic members of the microbiota as well as the pathogens and leading to a substantial delay in the restoration of a healthy microbiota. However, in some cases, infections can self-resolve without the intervention of antibiotics. In this Review, we explore the mechanisms underlying microbiota restoration following insult (antibiotic or otherwise) to the skin, oral cavity, and gastrointestinal and urogenital tracts, highlighting recovery by natural processes and after probiotic administration. 相似文献
996.
Rainone V Dubois G Temchura V Überla K Clivio A Nebuloni M Lauri E Trabattoni D Veas F Clerici M 《PloS one》2011,6(10):e26979
Mucosae-associated epithelial chemokine (MEC or CCL28) binds to CCR3 and CCR10 and recruits IgA-secreting plasma cells (IgA-ASCs) in the mucosal lamina propria. The ability of this chemokine to enhance migration of IgA-ASCs to mucosal sites was assessed in a mouse immunization model using HIV-1(IIIB) Virus-like particles (VLPs). Mice receiving either HIV-1(IIIB) VLPs alone, CCL28 alone, or the irrelevant CCL19 chemokine were used as controls. Results showed a significantly increased CCR3 and CCR10 expression on CD19(+) splenocytes of HIV-1(IIIB) VPL-CCL28-treated mice. HIV-1 Env-specific IFN-γ, IL-4 and IL-5 production, total IgA, anti-Env IgA as well as gastro-intestinal mucosal IgA-secreting plasma cells were also significantly augmented in these mice. Notably, sera and vaginal secretions from HIV-1(IIIB) VLP-CCL28-treated mice exhibited an enhanced neutralizing activity against both a HIV-1/B-subtype laboratory strain and a heterologous HIV-1/C-subtype primary isolate. These data suggest that CCL28 could be useful in enhancing the IgA immune response that will likely play a pivotal role in prophylactic HIV vaccines. 相似文献
997.
Hummelen R Macklaim JM Bisanz JE Hammond JA McMillan A Vongsa R Koenig D Gloor GB Reid G 《PloS one》2011,6(11):e26602
After menopause, many women experience vaginal dryness and atrophy of tissue, often attributed to the loss of estrogen. An understudied aspect of vaginal health in women who experience dryness due to atrophy is the role of the resident microbes. It is known that the microbiota has an important role in healthy vaginal homeostasis, including maintaining the pH balance and excluding pathogens. The objectives of this study were twofold: first to identify the microbiome of post-menopausal women with and without vaginal dryness and symptoms of atrophy; and secondly to examine any differences in epithelial gene expression associated with atrophy. The vaginal microbiome of 32 post-menopausal women was profiled using Illumina sequencing of the V6 region of the 16S rRNA gene. Sixteen subjects were selected for follow-up sampling every two weeks for 10 weeks. In addition, 10 epithelial RNA samples (6 healthy and 4 experiencing vaginal dryness) were acquired for gene expression analysis by Affymetrix Human Gene array. The microbiota abundance profiles were relatively stable over 10 weeks compared to previously published data on premenopausal women. There was an inverse correlation between Lactobacillus ratio and dryness and an increased bacterial diversity in women experiencing moderate to severe vaginal dryness. In healthy participants, Lactobacillus iners and L. crispatus were generally the most abundant, countering the long-held view that lactobacilli are absent or depleted in menopause. Vaginal dryness and atrophy were associated with down-regulation of human genes involved in maintenance of epithelial structure and barrier function, while those associated with inflammation were up-regulated consistent with the adverse clinical presentation. 相似文献
998.
Ganal MW Durstewitz G Polley A Bérard A Buckler ES Charcosset A Clarke JD Graner EM Hansen M Joets J Le Paslier MC McMullen MD Montalent P Rose M Schön CC Sun Q Walter H Martin OC Falque M 《PloS one》2011,6(12):e28334
SNP genotyping arrays have been useful for many applications that require a large number of molecular markers such as high-density genetic mapping, genome-wide association studies (GWAS), and genomic selection. We report the establishment of a large maize SNP array and its use for diversity analysis and high density linkage mapping. The markers, taken from more than 800,000 SNPs, were selected to be preferentially located in genes and evenly distributed across the genome. The array was tested with a set of maize germplasm including North American and European inbred lines, parent/F1 combinations, and distantly related teosinte material. A total of 49,585 markers, including 33,417 within 17,520 different genes and 16,168 outside genes, were of good quality for genotyping, with an average failure rate of 4% and rates up to 8% in specific germplasm. To demonstrate this array's use in genetic mapping and for the independent validation of the B73 sequence assembly, two intermated maize recombinant inbred line populations - IBM (B73×Mo17) and LHRF (F2×F252) - were genotyped to establish two high density linkage maps with 20,913 and 14,524 markers respectively. 172 mapped markers were absent in the current B73 assembly and their placement can be used for future improvements of the B73 reference sequence. Colinearity of the genetic and physical maps was mostly conserved with some exceptions that suggest errors in the B73 assembly. Five major regions containing non-colinearities were identified on chromosomes 2, 3, 6, 7 and 9, and are supported by both independent genetic maps. Four additional non-colinear regions were found on the LHRF map only; they may be due to a lower density of IBM markers in those regions or to true structural rearrangements between lines. Given the array's high quality, it will be a valuable resource for maize genetics and many aspects of maize breeding. 相似文献
999.
Chentouf M Dubois G Jahannaut C Castex F Lajoix AD Gross R Peraldi-Roux S 《PloS one》2011,6(8):e22954
Inappropriate food intake-related obesity and more importantly, visceral adiposity, are major risk factors for the onset of type 2 diabetes. Evidence is emerging that nutriment-induced β-cell dysfunction could be related to indirect induction of a state of low grade inflammation. Our aim was to study whether hyperphagia associated obesity could promote an inflammatory response in pancreatic islets leading to ?-cell dysfunction. In the hyperphagic obese insulin resistant male Zucker rat, we measured the level of circulating pro-inflammatory cytokines and estimated their production as well as the expression of their receptors in pancreatic tissue and β-cells. Our main findings concern intra-islet pro-inflammatory cytokines from fa/fa rats: IL-1β, IL-6 and TNFα expressions were increased; IL-1R1 was also over-expressed with a cellular redistribution also observed for IL-6R. To get insight into the mechanisms involved in phenotypic alterations, abArrays were used to determine the expression profile of proteins implicated in different membrane receptors signaling, apoptosis and cell cycle pathways. Despite JNK overexpression, cell viability was unaffected probably because of decreases in cleaved caspase3 as well as in SMAC/DIABLO and APP, involved in the induction and amplification of apoptosis. Concerning β-cell proliferation, decreases in important cell cycle regulators (Cyclin D1, p35) and increased expression of SMAD4 probably contribute to counteract and restrain hyperplasia in fa/fa rat islets. Finally and probably as a result of IL-1β and IL-1R1 increased expressions with sub-cellular redistribution of the receptor, islets from fa/fa rats were found more sensitive to both stimulating and inhibitory concentrations of the cytokine; this confers some physiopathological relevance to a possible autocrine regulation of β-cell function by IL-1β. These results support the hypothesis that pancreatic islets from prediabetic fa/fa rats undergo an inflammatory process. That the latter could contribute to β-cell hyperactivity/proliferation and possibly lead to progressive β-cell failure in these animals, deserves further investigations. 相似文献
1000.
Gregor Kijanka Richard Barry Hong Chen Edith Gould Stephanie K Seidlits Jasmin Schmid Maria Morgan David Y. Mason Jacqueline Cordell Derek Murphy 《Analytical biochemistry》2009,395(2):119-124
Many diagnostic antibodies are generated by immunization with whole cells or cell extracts and are shown by screening on tissue sections to label specific cell populations. However, their target molecule then needs to be identified, and this can be technically demanding. Here we describe the use of protein arrays to define the targets of new or uncharacterized monoclonal antibodies. The technique involves screening protein arrays containing thousands of recombinant human proteins. An initial experiment showed that a well-characterized monoclonal antibody against nucleophosmin identified 22 clones on the array encoding this protein. Next, the antibody JJ166, for which the antigen had not yet been identified, was screened. This antibody was generated by immunizing with a nuclear extract of Jurkat cells and was detected in immunohistochemistry due to its distinctive nuclear staining of lymphoid tissue cells. However, its molecular target had remained unidentified using traditional approaches. A protein array screen rapidly identified the mitotic spindle-associated molecule NUMA1 (nuclear mitotic apparatus protein 1). To confirm this putative specificity, JJ166 was shown to react with COS-1 cells transiently transfected with the complementary DNA for NUMA1. Furthermore, a commercially available antibody against NUMA1 showed nearly identical staining in immunohistochemistry on human tissue and cells. Overall, this method represents an effective and quick strategy for defining the protein targets of new or uncharacterized monoclonal antibodies identified as having diagnostic or other potential value on the basis of their immunostaining patterns. 相似文献