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61.
62.
的 了解血流感染肺炎克雷伯菌中CRISPR-Cas系统的分布特征并分析其与毒力基因和耐药的关系。方法 收集非重复血流感染肺炎克雷伯菌248株,使用Vitek2-Compact全自动微生物分析系统进行菌株鉴定及药物敏感性分析,PCR检测CRISPR-Cas系统3个相关基因(CRISPR1、CRISPR2和cas1)、筛查6种常见高毒力荚膜血清型(K1、K2、K5、 K20、K54和K57)、12种毒力基因及检测13种耐药基因,用χ2检验比较携带有CRISPR-Cas系统菌株与不携带CRISPR-Cas系统菌株毒力及耐药差异。结果 CRISPR-Cas系统的检出率为29.8%(74/248);K1型是携带CRISPR-Cas系统肺炎克雷伯菌的主要荚膜血清型,占 28.4%(21/74);除kpn基因外,携带CRISPR-Cas系统菌株的毒力基因检出率均大于不携带CRISPR-Cas系统菌株,其中7种差异有统计学意义;除对氨苄西林耐药率达100%外,携带有CRISPR-Cas系统菌株的其他抗菌药物耐药率均小于不携带有CRISPR-Cas系统菌株,其中13种差异有统计学意义;携带CRISPR-Cas系统菌株的耐药基因阳性率小于不携带CRISPR-Cas系统的菌株,且blaKPC、blaSHV、qnrS基因差异有统计学意义。结论 高毒力荚膜血清型肺炎克雷伯菌中主要为K1型携带CRISPR-Cas系统,携带CRISPR-Cas系统的肺炎克雷伯菌相对于不携带CRISPR-Cas系统菌株的毒力基因阳性率高,耐药率低,耐药基因的阳性率低。CRISPR-Cas系统可能能降低耐药基因在肺炎克雷伯菌中的水平传播,尤其是在K1型肺炎克雷伯菌。 相似文献
63.
Discoid lupus erythematosus (DLE) is the most common skin manifestation of lupus; however, the molecular mechanisms underlying DLE remain unknown. Therefore, we aimed to identify key differentially expressed genes (DEGs) in discoid lupus skin and investigate their potential pathways.To identify candidate genes involved in the occurrence and development of the disease, we downloaded the microarray datasets and GSE52471 from the Gene Expression Database (GEO). DEGs between discoid lupus skin and normal controls were selected using the GEO2R tool and Venn diagram software ( GSE72535http://bioinformatics.psb.ugent.be/webtools/Venn/). The Database for Annotation, Visualization, and Integrated Discovery (DAVID), Enrichr, and Cytoscape ClueGo were used to analyze the Kyoto Encyclopedia of Gene and Genome pathways and gene ontology. Protein-protein interactions (PPIs) of these DEGs were further assessed using the Search Tool for the Retrieval Interacting Genes version 10.0.Seventy three DEGs were co-expressed in both datasets. DEGs were predominantly upregulated in receptor signaling pathways of the immune response. In the PPI network, 69 upregulated genes were selected. Furthermore, 4 genes (CXCL10, ISG15, IFIH1, and IRF7) were found to be significantly upregulated in the RIG-I-like receptor signaling pathway, from analysis of Enrichr and Cytoscape ClueGo.The results of this study may provide new insights into the potential molecular mechanisms of DLE. However, further experimentation is required to confirm these findings. 相似文献
64.
65.
Shafqat R. Chaudhry Ilana S. Lendvai Sajjad Muhammad Philipp Westhofen Johannes Kruppenbacher Lukas Scheef Henning Boecker Dirk Scheele Rene Hurlemann Thomas M. Kinfe 《Brain stimulation》2019,12(3):643-651
Objective
To assay peripheral inter-ictal cytokine serum levels and possible relations with non-invasive vagus nerve stimulation (nVNS) responsiveness in migraineurs.Methods
This double-blinded, sham-controlled study enrolled 48 subjects and measured headache severity, frequency [headache days/month, number of total and mild/moderate/severe classified attacks/month], functional state [sleep, mood, body weight, migraine-associated disability] and serum levels of inflammatory markers [inter-ictal] using enzyme-linked immunoassays at baseline and after 2 months of adjunctive nVNS compared to sham stimulation and suitably matched controls.Results
No significant differences were observed at baseline and after 2 months for headache severity, total attacks/month, headache days/month and functional outcome [sleep, mood, disability] between verum and sham nVNS. However, the number of severe attacks/month significantly decreased in the verum nVNS group and circulating pro-inflammatory IL-1β was elevated significantly in the sham group compared to nVNS. Levels of anti-inflammatory IL-10 were significantly higher at baseline in both groups compared to healthy controls, but not at 2 months follow-up [p?<?0.05]. Concentrations of high-mobility group box-1 (HMGB-1), IL-6, tumor-necrosis factor-α (TNF-α), leptin, adiponectin, ghrelin remained unchanged [p?>?0.05]. No severe device-/stimulation-related adverse events occurred.Conclusion
2 months of adjunctive cervical nVNS significantly declined the number of severe attacks/month. Pro-inflammatory IL-1β plasma levels [inter-ictal] were higher in sham-treated migraine patients compared to verum nVNS. However, pro- [IL-6, HMGB-1, TNF-α, leptin] and anti-inflammatory [IL-10, adiponectin, ghrelin] mediators did not differ statistically. Profiling of neuroinflammatory circuits in migraine to predict nVNS responsiveness remains an experimental approach, which may be biased by pre-analytic variables warranting large-scale biobank-based systematic investigations [omics]. 相似文献66.
67.
《Vaccine》2019,37(31):4382-4391
Cancer-associated fibroblasts (CAFs), major components of the tumor microenvironment (TME), promote tumor growth and metastasis and inhibit the anti-tumor immune response. We previously constructed a DNA vaccine expressing human FAPα, which is highly expressed by CAFs, to target these cells in the TME, and observed limited anti-tumor effects in the 4T1 breast cancer model. When the treatment time was delayed until tumor nodes formed, the anti-tumor effect of the vaccine completely disappeared. In this study, to improve the safety and efficacy, we constructed a new FAPα-targeted vaccine containing only the extracellular domain of human FAPα with a tissue plasminogen activator signal sequence for enhanced antigen secretion and immunogenicity. The number of CAFs was more effectively reduced by CD8+ T cells induced by the new vaccine. This resulted in decreases in CCL2 and CXCL12 expression, leading to a significant decrease in the ratio of myeloid-derived suppressor cells in the TME. Moreover, when mice were treated after the establishment of tumors, the vaccine could still delay tumor growth. To facilitate the future application of the vaccine in clinical trials, we further optimized the gene codons and reduced the homology between the vaccine and the original sequence, which may be convenient for evaluating the vaccine distribution in the human body. These results indicated that the new FAPα-targeted vaccine expressing an optimized secreted human FAPα induced enhanced anti-tumor activity by reducing the number of FAPα+ CAFs and enhancing the recruitment of effector T cells in the 4T1 tumor model mice. 相似文献
68.
Toshiro Hara Rony Chanoch-Myers Nathan D. Mathewson Chad Myskiw Lyla Atta Lillian Bussema Stephen W. Eichhorn Alissa C. Greenwald Gabriela S. Kinker Christopher Rodman L. Nicolas Gonzalez Castro Hiroaki Wakimoto Orit Rozenblatt-Rosen Xiaowei Zhuang Jean Fan Tony Hunter Inder M. Verma Kai W. Wucherpfennig Itay Tirosh 《Cancer cell》2021,39(6):779-792.e11
69.
70.
目的:分析组蛋白去乙酰化酶抑制剂TSA处理前后,食管癌细胞株EC109中差异表达的非编码RNA(ncRNA)和mRNA表达谱,初步预测与TSA作用相关的ncRNA和mRNA。方法:采用MTT、细胞周期等方法检测TSA的效应;运用应用芯片技术分别检测TSA处理前后EC109细胞中ncRNA和mRNA表达谱变化,并对差异ncRNA和mRNA表达谱进行整合分析。结果:TSA以剂量时间依赖方式抑制细胞增殖,细胞周期阻滞和凋亡的发生。芯片检测共发现461个ncRNA和758个mRNA显著性差异表达,生物信息学分析显示差异涉及红比霉素、阿霉素代谢过程、氧化还原、核小体的装配、染色质结构组织和端粒的结构组织等。通过数据库分析预测及整合分析,得到了361个ncRNA-mRNA靶基因对。结论:差异表达的ncRNA和mRNA对TSA的生物学效应密切关联,为进一步研究基因功能及其在肿瘤中的生物学意义奠定基础。 相似文献