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31.
32.

Aims

The aim of this study was to evaluate the combined contribution of 12 genetic variants to the risk of coronary heart disease (CHD).

Methods

Through a comprehensive literature search for genetic variants involved in the CHD association study, we harvested a total of 10 genes (12 variants) for the current meta-analyses. These genes consisted of GPX1 (rs1050450), PPARD (rs2016520), ALOX15 (rs34210653), SELPLG (rs2228315), FCGR2A (rs1801274), CCL5 (rs2107538), CYP1A1 (rs4646903), TP53 (rs1042522), CX37 (rs1764391), and PECAM1 (rs668, rs12953, and rs1131012).

Results

A total of 45 studies among 23,314 cases and 28,430 controls were retrieved for the meta-analyses of 12 genetic variants. The results showed a significant association between the GPX1 rs1050450 polymorphism and CHD (odd ratio (OR) = 1.61, 95% confidence interval (CI) = 1.25–2.07, P = 0.0002). Other meta-analyses of the rest 11 variants suggested a lack of association with the risk of CHD.

Conclusion

Our results confirmed that GPX1 rs1050450 was associated with susceptibility to CHD in Chinese and Indian populations.  相似文献   
33.
We report a case of subcutaneous phaeohyphomycosis due to Phialophora verrucosa in a 64-year-old Chinese farmer suffering from CD4+ lymphopenia. He presented with diffuse and infiltrated plaques involving the entire face including the eyes, neck, occiput, and extending to the dorsal regions of his torso. The patient is notable for the discrete multifocal nature of the illness in the absence of disseminated infection and rarity of P. verrucosa as a cause of subcutaneous phaeohyphomycosis.  相似文献   
34.
Helicobacter pylori (H. pylori) plays an essential role in the development of various gastroduodenal diseases; however, no vaccines preventing H. pylori infection have been available now. This study was to evaluate the protective effect of rOmp22–HpaA fusion protein against H. pylori infection in mouse model and to screen the candidate to be used in the development of an oral vaccine against H. pylori. rOmp22, rHpaA, rOmp22+rHpaA, and rOmp22–HpaA groups were used to immunize mice with mLT63 as adjuvant by intragastric route, respectively, four times at 1-week intervals. Two weeks after last immunization, all of the animals were orally challenged with H. pylori NCTC11637 and then were killed after another 2 weeks. The mice gastric tissue of all groups was separated to detect the presence of infection by urease tests, to culture H. pylori, and to observe the histological characteristics. The protective effect against H. pylori challenge in mice immunized with rOmp22–HpaA fusion protein and mLT63 adjuvant was significantly higher than PBS and mLT63 control groups (P < 0.05), but no significant difference was detected among rOmp22, rHpaA, rOmp22+rHpaA, and rOmp22–HpaA groups (P > 0.05). rOmp22–HpaA fusion protein retained immunogenicity and could be used as an antigen candidate in the development of an oral vaccine against H. pylori infection.  相似文献   
35.
Most highly pathogenic avian influenza A viruses cause only mild clinical signs in ducks, serving as an important natural reservoir of influenza A viruses. However, we isolated two H5N1 viruses that are genetically similar but differ greatly in virulence in ducks. A/Chicken/Jiangsu/k0402/2010 (CK10) is highly pathogenic, whereas A/Goose/Jiangsu/k0403/2010 (GS10) is low pathogenic. To determine the genetic basis for the high virulence of CK10 in ducks, we generated a series of single-gene reassortants between CK10 and GS10 and tested their virulence in ducks. Expression of the CK10 PA or hemagglutinin (HA) gene in the GS10 context resulted in increased virulence and virus replication. Conversely, inclusion of the GS10 PA or HA gene in the CK10 background attenuated the virulence and virus replication. Moreover, the PA gene had a greater contribution. We further determined that residues 101G and 237E in the PA gene contribute to the high virulence of CK10. Mutations at these two positions produced changes in virulence, virus replication, and polymerase activity of CK10 or GS10. Position 237 plays a greater role in determining these phenotypes. Moreover, the K237E mutation in the GS10 PA gene increased PA nuclear accumulation. Mutant GS10 viruses carrying the CK10 HA gene or the PA101G or PA237E mutation induced an enhanced innate immune response. A sustained innate response was detected in the brain rather than in the lung and spleen. Our results suggest that the PA and HA gene-mediated high virus replication and the intense innate immune response in the brain contribute to the high virulence of H5N1 virus in ducks.  相似文献   
36.
Congenital human cytomegalovirus (HCMV) infection is the most frequent infectious cause of birth defects, primarily neurological disorders. Neural progenitor/stem cells (NPCs) are the major cell type in the subventricular zone and are susceptible to HCMV infection. In culture, the differentiation status of NPCs may change with passage, which in turn may alter susceptibility to virus infection. Previously, only early-passage (i.e., prior to passage 9) NPCs were studied and shown to be permissive to HCMV infection. In this study, NPC cultures derived at different gestational ages were evaluated after short (passages 3 to 6) and extended (passages 11 to 20) in vitro passages for biological and virological parameters (i.e., cell morphology, expression of NPC markers and HCMV receptors, viral entry efficiency, viral gene expression, virus-induced cytopathic effect, and release of infectious progeny). These parameters were not significantly influenced by the gestational age of the source tissues. However, extended-passage cultures showed evidence of initiation of differentiation, increased viral entry, and more efficient production of infectious progeny. These results confirm that NPCs are fully permissive for HCMV infection and that extended-passage NPCs initiate differentiation and are more permissive for HCMV infection. Later-passage NPCs being differentiated and more permissive for HCMV infection suggest that HCMV infection in fetal brain may cause more neural cell loss and give rise to severe neurological disabilities with advancing brain development.  相似文献   
37.
【目的】探讨新城疫病毒(Newcastle disease virus,NDV)基质(matrix,M)蛋白和禽细胞核磷蛋白B23.1在HEK-293T细胞中的相互作用。【方法】分别参照GenBank中NDV JS/5/05/Go株全基因序列(JN631747)和禽细胞核磷蛋白B23.1基因序列(NM205267),设计、合成扩增M基因和B23.1基因的引物,利用RT-PCR扩增出M基因和DF1细胞的B23.1基因,分别克隆至真核表达载体获得重组表达质粒pEGFP-M、pCMV-HA-M和pDsRed-B23.1;将pEGFP-M和pDsRed-B23.1共转染HEK-293T细胞,利用荧光显微镜观察M蛋白与B23.1蛋白的共定位;利用免疫共沉淀(Co-IP)技术进一步验证两种蛋白的相互作用。【结果】Western blot结果表明构建的重组质粒在转染的HEK-293T细胞中正确表达;荧光显微镜观察显示M蛋白与B23.1蛋白在核仁具有共定位特征;Co-IP进一步证实两者能发生相互作用。【结论】NDV M蛋白与禽细胞核磷蛋白B23.1存在相互作用,M蛋白可能通过与B23.1蛋白的相互作用进入核仁。  相似文献   
38.
Tissue factor pathway inhibitor-2 (Tfpi-2) is an important serine protease inhibitor in the extracellular matrix (ECM), but its precise physiological significance remains unknown. This work is part of a series of studies intended to investigate functional roles of Tfpi-2 and explore the underlying molecular mechanisms. First, we cloned and identified zebrafish Tfpi-2 (zTfpi-2) as an evolutionarily conserved protein essential for zebrafish development. We also demonstrated that ztfpi-2 is mainly expressed in the central nervous system (CNS) of zebrafish, and embryonic depletion of ztfpi-2 caused severe CNS defects. In addition, changes of neural markers, including pax2a, egr2b, huC, ngn1, gfap and olig2, confirmed the presence of developmental abnormalities in the relevant regions of ztfpi-2 morphants. Using microarray analysis, we found that members of the Notch pathway, especially her4 and mib, which mediate lateral inhibition in CNS development, were also downregulated. Intriguingly, both her4 and mib were able to partially rescue the ztfpi-2 morphant phenotype. Furthermore, Morpholino knockdown of ztfpi-2 resulted in upregulation of neuronal markers while downregulation of glial markers, providing evidence that the Notch pathway is probably involved in ztfpi-2-mediated CNS development.  相似文献   
39.
To identify DNA aptamers demonstrating binding specificity for Shigella dysenteriae, a whole-bacterium Systemic Evolution of Ligands by Exponential enrichment (SELEX) method was applied to a combinatorial library of single-stranded DNA (ssDNA) molecules. After several rounds of selection using S. dysenteriae as the target, the highly enriched oligonucleotide pool was sequenced and then grouped into different families based on primary sequence homologies and similarities in the secondary structures. Aptamer S 1, which showed particularly high binding affinity in preliminary studies, was chosen for further characterisation. This aptamer displayed a dissociation constant (Kd value) of 23.47 ± 2.48 nM. Binding assays to assess the specificity of aptamer S 1 showed high binding affinity for S. dysenteriae and low apparent binding affinity for other bacteria. The ssDNA aptamers generated may serve as a new type of molecular probe for microbial pathogens, as it has the potential to overcome the tedious isolation and purification requirements for complex targets.  相似文献   
40.
The objective of this study was to investigate the influence of solids retention time (SRT) on membrane fouling and the characteristics of biomacromolecules. Four identical laboratory-scale membrane bioreactors (MBRs) were operated with SRTs for 10, 20, 40 and 80 days. The results indicated that membrane fouling occurred faster and more readily under short SRTs. Fouling resistance was the primary source of filtration resistance. The modified fouling index (MFI) results suggested that the more ready fouling at short SRTs could be attributed to higher concentrations of soluble microbial products (SMP). Fourier transform infrared (FTIR) spectra indicated that the SRT had a weak influence on the functional groups of the total extracellular polymeric substances (TEPS) and SMP. However, the MBR under a short SRT had more low-molecular-weight (MW) compounds (<1 kDa) and fewer high-MW compounds (>100 kDa). Aromatic protein and tryptophan protein-like substances were the dominant groups in the TEPS and SMP, respectively.  相似文献   
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