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31.
Chen JG Xia JC Liang XT Pan K Wang W Lv L Zhao JJ Wang QJ Li YQ Chen SP He J Huang LX Ke ML Chen YB Ma HQ Zeng ZW Zhou ZW Chang AE Li Q 《International journal of biological sciences》2011,7(1):53-60
In this study, we characterized the intratumoral expression of IL-17 and CD8(+) TILs in gastric adenocarcinoma patients after resection and determined the correlation between the survival probability of gastric adenocarcinoma patients and the expression of IL-17 in tumor. Expression of IL-17 and CD8 was assessed by immunohistochemistry, and the prognostic effects of intratumoral IL-17 expression and CD8(+) TILs were evaluated by Cox regression and Kaplan-Meier analysis. Immunohistochemical detection revealed the presence of IL-17 and CD8(+) cells in gastric adenocarcinoma tissue samples (90.6%, 174 out of 192 patients and 96.9%, 186 out of 192 patients, respectively). We have also found that intratumoral IL-17 expression was significantly correlated with age (p=0.004) and that the number of CD8(+)TILs was significantly correlated with UICC staging (p=0.012) and the depth of tumor invasion (p=0.022). The five-year overall survival probability among patients intratumorally expressing higher levels of IL-17 was significantly better than those expressing lower levels of IL-17 (p=0.036). Multivariate Cox proportional hazard analyses revealed that intratumoral IL-17 expression (HR: 0.521; 95% CI: 0.329-0.823; p=0.005) was an independent factor affecting the five-year overall survival probability. We conclude that low levels of intratumoral IL-17 expression may indicate poor prognosis in gastric adenocarcinoma patients. 相似文献
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33.
Bayesian image processing formalisms which incorporatea priori information about valued-uncorrelated and valued-correlated (patterned) source distributions are introduced and the corresponding
iterative algorithms are derived using the EM technique. Striking improvement in image processing is demonstrated when applying
these algorithms to Poisson and Gaussian randomized data in one-dimensional cases. 相似文献
34.
Agnès Baudin-Baillieu Céline Fabret Xue-hai Liang Dorota Piekna-Przybylska Maurille J. Fournier Jean-Pierre Rousset 《Nucleic acids research》2009,37(22):7665-7677
Important regions of rRNA are rich in nucleotide modifications that can have strong effects on ribosome biogenesis and translation efficiency. Here, we examine the influence of pseudouridylation and 2′-O-methylation on translation accuracy in yeast, by deleting the corresponding guide snoRNAs. The regions analyzed were: the decoding centre (eight modifications), and two intersubunit bridge domains—the A-site finger and Helix 69 (six and five modifications). Results show that a number of modifications influence accuracy with effects ranging from 0.3- to 2.4-fold of wild-type activity. Blocking subsets of modifications, especially from the decoding region, impairs stop codon termination and reading frame maintenance. Unexpectedly, several Helix 69 mutants possess ribosomes with increased fidelity. Consistent with strong positional and synergistic effects is the finding that single deletions can have a more pronounced phenotype than multiple deficiencies in the same region. Altogether, the results demonstrate that rRNA modifications have significant roles in translation accuracy. 相似文献
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Julie M. Grossman Brendan E. O’Neill Siu Mui Tsai Biqing Liang Eduardo Neves Johannes Lehmann Janice E. Thies 《Microbial ecology》2010,60(1):192-205
We compared the microbial community composition in soils from the Brazilian Amazon with two contrasting histories; anthrosols
and their adjacent non-anthrosol soils of the same mineralogy. The anthrosols, also known as the Amazonian Dark Earths or
terra preta, were managed by the indigenous pre-Colombian Indians between 500 and 8,700 years before present and are characterized
by unusually high cation exchange capacity, phosphorus (P), and calcium (Ca) contents, and soil carbon pools that contain
a high proportion of incompletely combusted biomass as biochar or black carbon (BC). We sampled paired anthrosol and unmodified
soils from four locations in the Manaus, Brazil, region that differed in their current land use and soil type. Community DNA
was extracted from sampled soils and characterized by use of denaturing gradient gel electrophoresis (DGGE) and terminal restriction
fragment length polymorphism. DNA bands of interest from Bacteria and Archaea DGGE gels were cloned and sequenced. In cluster
analyses of the DNA fingerprints, microbial communities from the anthrosols grouped together regardless of current land use
or soil type and were distinct from those in their respective, paired adjacent soils. For the Archaea, the anthrosol communities
diverged from the adjacent soils by over 90%. A greater overall richness was observed for Bacteria sequences as compared with
those of the Archaea. Most of the sequences obtained were novel and matched those in databases at less than 98% similarity.
Several sequences obtained only from the anthrosols grouped at 93% similarity with the Verrucomicrobia, a genus commonly found in rice paddies in the tropics. Sequences closely related to Proteobacteria and Cyanobacteria sp. were recovered only from adjacent soil samples. Sequences related to Pseudomonas, Acidobacteria, and Flexibacter sp. were recovered from both anthrosols and adjacent soils. The strong similarities among the microbial communities present
in the anthrosols for both the Bacteria and Archaea suggests that the microbial community composition in these soils is controlled
more strongly by their historical soil management than by soil type or current land use. The anthrosols had consistently higher
concentrations of incompletely combusted organic black carbon material (BC), higher soil pH, and higher concentrations of
P and Ca compared to their respective adjacent soils. Such characteristics may help to explain the longevity and distinctiveness
of the anthrosols in the Amazonian landscape and guide us in recreating soils with sustained high fertility in otherwise nutrient-poor
soils in modern times. 相似文献
37.
Beclin1-binding UVRAG targets the class C Vps complex to coordinate autophagosome maturation and endocytic trafficking 总被引:1,自引:0,他引:1
Liang C Lee JS Inn KS Gack MU Li Q Roberts EA Vergne I Deretic V Feng P Akazawa C Jung JU 《Nature cell biology》2008,10(7):776-787
Autophagic and endocytic pathways are tightly regulated membrane rearrangement processes that are crucial for homeostasis, development and disease. Autophagic cargo is delivered from autophagosomes to lysosomes for degradation through a complex process that topologically resembles endosomal maturation. Here, we report that a Beclin1-binding autophagic tumour suppressor, UVRAG, interacts with the class C Vps complex, a key component of the endosomal fusion machinery. This interaction stimulates Rab7 GTPase activity and autophagosome fusion with late endosomes/lysosomes, thereby enhancing delivery and degradation of autophagic cargo. Furthermore, the UVRAG-class-C-Vps complex accelerates endosome-endosome fusion, resulting in rapid degradation of endocytic cargo. Remarkably, autophagosome/endosome maturation mediated by the UVRAG-class-C-Vps complex is genetically separable from UVRAG-Beclin1-mediated autophagosome formation. This result indicates that UVRAG functions as a multivalent trafficking effector that regulates not only two important steps of autophagy - autophagosome formation and maturation - but also endosomal fusion, which concomitantly promotes transport of autophagic and endocytic cargo to the degradative compartments. 相似文献
38.
Shuang-Xia Zhao Chun-Ming Pan Huang-Ming Cao Bing Han Jing-Yi Shi Jun Liang Guan-Qi Gao Yong-De Peng Qing Su Jia-Lun Chen Jia-Jun Zhao Huai-Dong Song 《PloS one》2010,5(3)
To determine whether genetic heterogeneity exists in patients with Graves'' disease (GD), the cytotoxic T-lymphocyte associated 4 (CTLA-4) gene, which is implicated a susceptibility gene for GD by considerable genetic and immunological evidence, was used for association analysis in a Chinese Han cohort recruited from various geographic regions. Our association study for the SNPs in the CTLA4 gene in 2640 GD patients and 2204 control subjects confirmed that CTLA4 is the susceptibility gene for GD in the Chinese Han population. Moreover, the logistic regression analysis in the combined Chinese Han cohort revealed that SNP rs231779 (allele frequencies p = 2.81×10−9, OR = 1.35, and genotype distributions p = 2.75×10−9, OR = 1.42) is likely the susceptibility variant for GD. Interestingly, the logistic regression analysis revealed that SNP rs35219727 may be the susceptibility variant to GD in the Shandong population; however, SNP, rs231779 in the CTLA4 gene probably independently confers GD susceptibility in the Xuzhou and southern China populations. These data suggest that the susceptibility variants of the CTLA4 gene varied between the different geographic populations with GD. 相似文献
39.
40.
Expression of baculovirus anti-apoptotic genes p35 and op-iap in cotton (Gossypium hirsutum L.) enhances tolerance to verticillium wilt 总被引:1,自引:0,他引:1