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91.
Acute bronchitis is a lower respiratory tract lung infection that causes bronchial inflammation. The known protein drug targets are peptidoglycan D, D-transpeptidase, and DNA topoisomerase 4 subunit A for bronchitis linked infections. These are the membrane associated macromolecules which takes a major role in the formation of cell wall membrane by synthesising the cross-linked peptidoglycan. Therefore, it is of interest to design molecules with improved binding features with these protein targets. Hence, we document the molecular docking analysis data of four phytocompounds from Acacia farnesiana having optimal binding features with these targets linked to bronchitis for further consideration.  相似文献   
92.
Avian infectious bronchitis virus(IBV) is a Gammacoronavirus in the family Coronaviridae and causes highly contagious respiratory disease in chickens. Innate immunity plays significant roles in host defense against IBV. Here, we explored the interaction between IBV and the host innate immune system. Severe histopathological lesions were observed in the tracheal mucosa at 3–5days post inoculation(dpi) and in the kidney at 8 dpi, with heavy viral loads at 1–11 and 1–28 dpi,respectively. The expression of m RNAs encoding Toll-like receptor(TLR) 3 and TLR7 were upregulated at 3–8 dpi, and that of TIR-domain-containing adapter-inducing interferon(IFN) β(TRIF) was upregulated at 21 dpi in the trachea and kidney. Myeloid differentiation primary response protein 88(My D88) was upregulated in the trachea during early infection. Tumor necrosis factor receptor-associated factor(TRAF) 3 and TRAF6 were upregulated expression in both tissues.Moreover, melanoma differentiation-associated protein 5(MDA5), laboratory of genetics and physiology 2(LGP2), stimulator of IFN genes(STING), and mitochondrial antiviral signaling protein(MAVS), as well as TANK binding kinase 1(TBK1), inhibitor of kappa B kinase(IKK) ?, IKKα, IKKβ,IFN regulatory factor(IRF) 7, nuclear factor of kappa B(NF-κB), IFN-α, IFN-β, various interleukins(ILs), and macrophage inflammatory protein-1β(MIP-1β) were significantly upregulated in the trachea and downregulated in the kidney. These results suggested that the TLR and MDA5 signaling pathways and innate immune cytokine were induced after IBV infection. Additionally,consistent responses to IBV infection were observed during early infection, with differential and complicated responses in the kidney.  相似文献   
93.
参考Genbank上发表的IBV S1纤突蛋白基因序列,设计了一对引物,对鸡传染性支气管炎病毒青岛腺胃分离株(SD/97/02)RNA进行RT-PCR扩增。将PCR产物克隆入pMD18-T载体中进行序列测定和分析。序列分析表明,该毒株的S1基因的G+C%含量较少,为37.0%,存在HindⅢ,BamHⅠ,BglIⅠ,SacⅠ和SalⅠ位点,无EcoRⅠ位点,与其他毒株的同源性在87.02%-94.21%之间,在第154-429nt处为高度的变异区;将基因序列翻译成氨基酸后,假定的S1蛋白由540个氨基酸组成,等电点8.24,在蛋白质内部存在18个Cys,在S1与S2蛋白之间的剪切位点为HRRRR,这与大多数IBV毒株(RRF/SRR)不一样,有三个区域的氨基酸序列高度保守;169-181aa,230-250aa,485-506aa;与其他毒株进行抗原性比较后发现,在该毒株的320-326aa及390-401aa处的抗原表位消失,而在325-345aa、379-389aa处则出现了很强的抗原表位;第438-444aa处,其他IBV毒株(除ZJ971株外)原来存在的强抗原位点在本毒株中消失。在53-65位的氨基酸抗原性与其他毒株相比明显变弱。  相似文献   
94.
从自然发生的鸡肾病变型传染性支气管炎病例采集病死鸡肾脏为材料,通过接种9-11日龄SPF鸡胚尿囊腔,进行病毒的分离和传代,分离到1株病毒(FX),敏感鸡人工感染后出现呼吸症状,剖检病鸡时大我鸡肾肿大并有尿酸盐沉积,病毒能死鸡胚和产生侏儒胚;病毒能干扰鸡新城疫病毒LaSota株在鸡胚中增殖,病毒经电镜观察,其大小在80-120nm之间,囊膜外有纤,病毒经IBV单抗ELISA检测呈强阳性反应。研究结果初步表明,FX毒株为肾型IBV。  相似文献   
95.
对IBV肾型毒株JS/95 /0 3和呼吸型毒株SD/97/0 1的S1全基因进行了扩增、克隆和序列测定 ,将两毒株的S1基因序列与 10个参考毒株进行了比较。结果表明 ,JS/95 /0 3和SD/97/0 1分别与M41和H12 0株亲缘关系最近 ,它们可能是疫苗毒株的变异株。JS/95 /0 3和SD/97/0 1间的亲缘关系也较近 ,两者S1蛋白中只有 2 4个氨基酸的差异 ,其中有 15个位于前 130个氨基酸中 ,第 116位氨基酸可能与毒株的致病性有关。对两毒株S1蛋白的二级结构进行了预测和比较 ,结果发现 ,一个或极少数氨基酸的差异即可导致S1蛋白二级结构和抗原性的改变  相似文献   
96.
根据GenBank已经发表的传染性支气管炎病毒(IBV)N全基因组序列设计引物,对IBV 793/B分离毒株N基因进行克隆与序列分析.结果表明,IBV 793/B的N基因由1229bp组成,与GenBank已发表的11株IBV的N基因相比较,IBV 793/B的N基因共有88处点突变,在第991位发生了一个核苷酸的缺失.N基因的核苷酸同源性为86.9%~91.4%,氨基酸同源性为75.8%~77.5%.表明IBV 93/B的N基因存在着较大的变异性.  相似文献   
97.
对2000-2004年从中国9个省市分离到的13株IBV的核蛋白基因片段进行序列测定及分析的结果表明,13株IBV分离株核蛋白基因均含有一个长1230bp的ORF,但存在基因突变现象.与GenBank中的42株参考毒株核蛋白基因序列进行比较和分析,系统进化关系显示55株IBV毒株分属于9个群.第Ⅰ-Ⅲ群主要包括美国、日本、荷兰等国家以及中国的部分IBV分离株和疫苗株.其中本研究中的CK/CH/LHN/00I可能为一株分离的疫苗毒,CK/CH/LSD/03I、CK/CH/LDL/01I可能为重组毒.而中国近十年来分离的IBV毒株主要分布在第Ⅵ-Ⅷ群中,此3群内IBV毒株之间N蛋白推导氨基酸同源性为88.3%~100%,与其他各群之间同源性为62.3%~95.1%.因此,此基因型的IBV毒株可能在中国已有较长时期的存在且发生了较大程度的变异.其中第Ⅵ群中两株韩国分离株与中国IBV分离株具有较近的亲缘关系.以上结果表明,中国大多数IBV分离株在N基因进化关系上较为独立,与国外毒株相比,和韩国毒株进化关系密切.此外,中国IBV毒株基因重组现象更加普遍,尤其是疫苗毒和野毒之间的重组.  相似文献   
98.

Background

The coexistence of gastroesophageal reflux disease (GERD) and COPD has been recognized, but there has been no comprehensive evaluation of the impact of GERD on COPD-related health status and patient-centered outcomes.

Methods

Cross-sectional and longitudinal study of 4,483 participants in the COPDGene cohort who met GOLD criteria for COPD. Physician-diagnosed GERD was ascertained by questionnaire. Clinical features, spirometry and imaging were compared between COPD subjects without versus with GERD. We evaluated the relationship between GERD and symptoms, exacerbations and markers of microaspiration in univariate and multivariate models. Associations were additionally tested for the confounding effect of covariates associated with a diagnosis of GERD and the use of proton-pump inhibitor medications (PPIs). To determine whether GERD is simply a marker for the presence of other conditions independently associated with worse COPD outcomes, we also tested models incorporating a GERD propensity score.

Results

GERD was reported by 29% of subjects with female predominance. Subjects with GERD were more likely to have chronic bronchitis symptoms, higher prevalence of prior cardiovascular events (combined myocardial infarction, coronary artery disease and stroke 21.3% vs. 13.4.0%, p < 0.0001). Subjects with GERD also had more severe dyspnea (MMRC score 2.2 vs. 1.8, p < 0.0001), and poorer quality of life (QOL) scores (St. George’s Respiratory Questionnaire (SGRQ) total score 41.8 vs. 34.9, p < 0.0001; SF36 Physical Component Score 38.2 vs. 41.4, p < 0.0001). In multivariate models, a significant relationship was detected between GERD and SGRQ (3.4 points difference, p < 0.001) and frequent exacerbations at baseline (≥2 exacerbation per annum at inclusion OR 1.40, p = 0.006). During a mean follow-up time of two years, GERD was also associated with frequent (≥2/year exacerbations OR 1.40, p = 0.006), even in models in which PPIs, GERD-PPI interactions and a GERD propensity score were included. PPI use was associated with frequent exacerbator phenotype, but did not meaningfully influence the GERD-exacerbation association.

Conclusions

In COPD the presence of physician-diagnosed GERD is associated with increased symptoms, poorer QOL and increased frequency of exacerbations at baseline and during follow-up. These associations are maintained after controlling for PPI use. The PPI-exacerbations association could result from confounding-by-indication.  相似文献   
99.
100.
对2000-2004年从中国9个省市分离到的13株IBV的核蛋白基因片段进行序列测定及分析的结果表明,13株IBV分离株核蛋白基因均含有一个长1230bp的ORF,但存在基因突变现象。与GenBank中的42株参考毒株核蛋白基因序列进行比较和分析,系统进化关系显示55株IBV毒株分属于9个群。第Ⅰ-Ⅲ群主要包括美国、日本、荷兰等国家以及中国的部分IBV分离株和疫苗株。其中本研究中的CK/CH/LHN/00I可能为一株分离的疫苗毒,CK/CH/LSD/03I、CK/CH/LDL/01I可能为重组毒。而中国近十年来分离的IBV毒株主要分布在第Ⅵ-Ⅷ群中,此3群内IBV毒株之间N蛋白推导氨基酸同源性为88.3%~100%,与其他各群之间同源性为62.3%~95.1%。因此,此基因型的IBV毒株可能在中国已有较长时期的存在且发生了较大程度的变异。其中第Ⅵ群中两株韩国分离株与中国IBV分离株具有较近的亲缘关系。以上结果表明,中国大多数IBV分离株在N基因进化关系上较为独立,与国外毒株相比,和韩国毒株进化关系密切。此外,中国IBV毒株基因重组现象更加普遍,尤其是疫苗毒和野毒之间的重组。  相似文献   
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