排序方式: 共有46条查询结果,搜索用时 0 毫秒
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Olga Pivovarova Christian von Loeffelholz Iryna Ilkavets Carsten Sticht Sergei Zhuk Veronica Murahovschi Sonja Lukowski Stephanie D?cke Jennifer Kriebel Tonia de las Heras Gala Anna Malashicheva Anna Kostareva Johan F Lock Martin Stockmann Harald Grallert Norbert Gretz Steven Dooley Andreas FH Pfeiffer Natalia Rudovich 《Cell cycle (Georgetown, Tex.)》2015,14(14):2293-2300
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Tabassam FH Graham DY Yamaoka Y 《American journal of physiology. Gastrointestinal and liver physiology》2011,301(4):G601-G611
Paxillin is involved in the regulation of Helicobacter pylori-mediated gastric epithelial cell motility. We investigated the signaling pathways regulating H. pylori-induced paxillin phosphorylation and the effect of the H. pylori virulence factors cag pathogenicity island (PAI) and outer inflammatory protein (OipA) on actin stress fiber formation, cell phenotype, and IL-8 production. Gastric cell infection with live H. pylori induced site-specific phosphorylation of paxillin tyrosine (Y) 31 and Y118 in a time- and concentration-dependent manner. Activated paxillin localized in the cytoplasm at the tips of H. pylori-induced actin stress fibers. Isogenic oipA mutants significantly reduced paxillin phosphorylation at Y31 and Y118 and reduced actin stress fiber formation. In contrast, cag PAI mutants only inhibited paxillin Y118 phosphorylation. Silencing of epidermal growth factor receptor (EGFR), focal adhesion kinase (FAK), or protein kinase B (Akt) expression by small-interfering RNAs or inhibiting kinase activity of EGFR, Src, or phosphatidylinositol 3-kinase (PI3K) markedly reduced H. pylori-induced paxillin phosphorylation and morphologic alterations. Reduced FAK expression or lack of Src kinase activity suppressed H. pylori-induced IL-8 production. Compared with infection with the wild type, infection with the cag PAI mutant and oipA mutant reduced IL-8 production by nearly 80 and 50%. OipA-induced IL-8 production was FAK- and Src-dependent, although a FAK/Src-independent pathway for IL-8 production also exists, and the cag PAI may be mainly involved in this pathway. We propose paxillin as a novel cellular target for converging H. pylori-induced EGFR, FAK/Src, and PI3K/Akt signaling to regulate cytoskeletal reorganization and IL-8 production in part, thus contributing to the H. pylori-induced diseases. 相似文献
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Shifting polio eradication strategies may have generated fear and “resistance” to the eradication program in Aligarh, India during the summer of 2009. Participant observation and formal interviews with 107 people from May to August 2009 indicated that the intensified frequency of vaccination was correlated with patients'' doubt in the efficacy of the vaccine. This doubt was exacerbated in a few cases as families were uninformed of the use of monovalent mOPV1, while P3 cases continued to occur. Many families had also come to believe that their children had been adversely affected by OPV after being told the vaccine carried no risk. Though polio is now largely eradicated in India, with only a single case in 2011, greater transparency about changes with vaccination policy may need to be considered to build trust with the public in future eradication programs. 相似文献
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Yumin Xu Hui Wang Shishan Bao Fazal Tabassam Wei Cai Xiaogang Xiang Gangde Zhao Haiqing Wu Ting Gao Hai Li Qing Xie 《PloS one》2013,8(7)
Background
Acute-on-chronic liver failure (ACLF) is an acute deterioration of established liver disease. Blocking the TNF (tumor necrosis factor)/TNFR (tumor necrosis factor receptor) 1 pathway may reduce hepatocyte apoptosis/necrosis, and subsequently decrease mortality during development of ACLF. We demonstrated that a long-acting TNF antagonist (soluble TNF receptor: IgG Fc [sTNFR:IgG-Fc]) prevented/reduced development of acute liver failure by blocking the TNF/TNFR1 (TNFRp55) pathway. However, it is still unclear if sTNFR:IgG-Fc can inhibit hepatocyte damage during development of ACLF.Methodology
Chronic liver disease (liver fibrosis/cirrhosis) was induced in Wistar rats by repeatedly challenging with human serum albumin (HSA), and confirmed by histopathology. ACLF was induced with D-galactosamine (D-GalN)/lipopolysaccharide (LPS) i.p. in the rats with chronic liver disease. Serum and liver were collected for biochemical, pathological and molecular biological examinations.Principal Findings
Reduced mortality was observed in sTNFR:IgG-Fc treated ACLF rats, consistent with reduced interleukin (IL)-6 levels in serum and liver, as well as reduced hepatic caspase-3 activity, compared to that of mock treated group. Reduced hepatic damage was confirmed with histopathology in the sTNFR:IgG-Fc treated group, which is consistent with reduced Bcl-2 and Bax, at mRNA and protein levels, but increased hepatocyte proliferation (PCNA). This is also supported by the findings that caspase-3 production was up-regulated significantly in ACLF group compared to the mock treated group. Moreover, up-regulated caspase-3 was inhibited following sTNFR:IgG-Fc treatment. Finally, there was up-regulation of hepatic IL-22R in sTNFR:IgG-Fc treated ACLF rats.Conclusions
sTNFR:IgG-Fc improved survival rate during development of ACLF via ameliorating liver injury with a potential therapeutic value. 相似文献27.
M Gowda Y Zhao T Würschum C FH Longin T Miedaner E Ebmeyer R Schachschneider E Kazman J Schacht J-P Martinant M F Mette J C Reif 《Heredity》2014,112(5):552-561
The accuracy of genomic selection depends on the relatedness between the members of the
set in which marker effects are estimated based on evaluation data and the types for which
performance is predicted. Here, we investigate the impact of relatedness on the
performance of marker-assisted selection for fungal disease resistance in hybrid wheat. A
large and diverse mapping population of 1739 elite European winter wheat inbred lines and
hybrids was evaluated for powdery mildew, leaf rust and stripe rust resistance in
multi-location field trials and fingerprinted with 9 k and 90 k SNP arrays.
Comparison of the accuracies of prediction achieved with data sets from the two marker
arrays revealed a crucial role for a sufficiently high marker density in genome-wide
association mapping. Cross-validation studies using test sets with varying degrees of
relationship to the corresponding estimation sets revealed that close relatedness leads to
a substantial increase in the proportion of total genotypic variance explained by the
identified QTL and consequently to an overoptimistic judgment of the precision of
marker-assisted selection. 相似文献
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The effective population size of Anopheles gambiae in Kenya: implications for population structure 总被引:4,自引:0,他引:4
We estimated current and long-term effective population size (Ne) of two
Anopheles gambiae (savanna cytotype) populations in Kenya. Temporal
variation at nine microsatellite loci in each population sampled 7 and 9
years apart and genetic diversity in each sample were analyzed to answer
the following questions. (1) Do bottlenecks occur in Kenyan populations of
A. gambiae? (2) How variable are different populations with respect to
their current and long-term Ne values? (3) What are the implications of
these results on population structure and history? The estimates of Ne of
Asembo and Jego were 6,359 and 4,258, respectively, and the lower 95%
limits were 2,455 and 1,669, respectively. Thus, despite the typical
observation of low density at the village level during the dry season,
large populations are maintained annually. Large current Ne is consistent
with previous studies showing low differentiation across the continent,
especially under Wright's isolation-by-distance model. Current Ne in Asembo
was 1.5-fold higher than in Jego, but this difference was not significant.
Long-term Ne in Asembo (22,667) was 2.9-fold higher than that in Jego
(7,855) based on the stepwise mutation model. The difference between
populations was significant at both time points regardless of whether
long-term Ne values were calculated based on the stepwise mutation model or
the infinite-alleles model. Heterozygosity in Jego declined significantly
between 1987 (59%) and 1996 (54%), whereas heterozygosity in Asembo was
stable (66%-65%). Despite the relatively high and significant
differentiation between Asembo and Jego (FST = 0.072-0.10, RST = 0.037-
0.038), all alleles in Jego were found in Asembo but not vice versa. All of
these findings suggest that lower Ne in Jego magnifies differentiation
between the two populations. The long-term Ne was biased downward, because
its calculation was based on an upper bound estimate of microsatellite
mutation rate. Ne values based on mtDNA and allozymes were an order of
magnitude higher. Long-term Ne therefore, is probably measured in hundreds
of thousands and hence does not support a recent expansion of this species
from a small population.
相似文献
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Single-copy nuclear DNAs (scnDNAs) of eight species of arvicoline and six
species of murine rodents were compared using DNA-DNA hybridization. The
branching pattern derived from the DNA comparisons is congruent with the
fossil evidence and supported by comparative biochemical, chromosomal, and
morphological studies. The recently improved fossil record for these
lineages provides seven approximate divergence dates, which were used to
calibrate the DNA-hybridization data. The average rate of scnDNA divergence
was estimated as 2.5%/Myr. This is approximately 10 times the rate in the
hominoid primates. These results agree with previous reports of accelerated
DNA evolution in muroid rodents and extend the DNA-DNA hybridization data
set of Brownell.
相似文献
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