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951.
Necropsied lung tissues of three fatal cases with avian influenza A virus (H5N1) infection in Vietnam were analyzed to detect H5N1 virus-infected cells. Formalin-fixed and paraffin-embedded lung tissue sections showed typical histological features of diffuse alveolar damage (DAD) in all cases. Immunohistochemistry for the influenza A virus nucleoprotein antigen revealed positive signals of bronchiolar and alveolar epithelial cells in only one patient, who exhibited DAD with an exudative phase and died on the 6th day after onset. However, no signal was detected in the other two cases of DAD with a proliferative phase. These patients died on day 16 and day 17 after onset, respectively. H5N1 virus antigens were detected predominantly in epithelial cells in terminal bronchioles and in alveoli, i.e., type I and type II alveolar pneumocytes, and in alveolar macrophages. The pathogenesis of exudative DAD caused by H5N1 infection is discussed.  相似文献   
952.
953.
We examined the membrane expression of inducible Hsp70 and HSP receptors like TLR2, TLR4, CD14, CD36, CD40 and CD91 on fibroblast-like synovial cells (SC) derived from synovial tissue in 23 patients with rheumatoid arthritis (RA), who underwent synovectomy by using flow cytometric analysis. For comparison, autologous skin fibroblasts (SF) derived from the operation wound were tested. Significantly higher Hsp70 expression was found on synovial cells than on skin fibroblasts (median SC 21.4% x SF 5.0%, P < 0.001). Both synovial cells and skin fibroblasts expressed high levels of cell surface CD91 (median SC 80.2% x SF 79.2%), however, no or low levels of CD14, CD40, TLR2, TLR4 and CD36. Further, we observed high co-expression of CD91 and Hsp70 on RA synovial cells (median 18.6%), while skin fibroblasts showed only background Hsp70 expression (median 3.9%, P < 0.001). Since we demonstrated the high prevalence of inducible Hsp70 in RA synovial fluids, we speculate that Hsp70 might be captured onto the membrane of synovial cells from the extracellular space via the CD91 receptor. The significance of the Hsp70 interaction with synovial cells via CD91 remains undefined, but may mediate other non-immune purposes.  相似文献   
954.
955.
Using a live cell, high-throughput caspase-3 activator assay, we have identified a novel series of 4-anilinoquinazolines as inducers of apoptosis. In this report, we discuss the discovery of 2-chloro-N-(4-methoxyphenyl)-N-methylquinazolin-4-amine, compound 2b (EP128265, MPI-0441138) as a highly active inducer of apoptosis (EC50 for caspase activation of 2 nM) and as a potent inhibitor of cell proliferation (GI50 of 2 nM) in T47D cells. Compound 2b inhibited tubulin polymerization, was effective in cells overexpressing ABC transporter Pgp-1, and was efficacious in the MX-1 human breast and PC-3 prostate cancer mouse models. In contrast to the SAR of 4-anilinoquinazolines as EGFR kinase inhibitors, the methyl group on the nitrogen linker was essential for the apoptosis-inducing activity of 4-anilinoquinazolines and substitution in the 6- and 7-positions of the quinazoline core structure decreased potency.  相似文献   
956.
Human enterovirus 71 (EV71) is the major etiologic agent of hand, foot, and mouth disease (HFMD). EV71 outbreaks have been reported in Dak Lak in recent years, however, the genotypes/subgenotypes information and phylogeny of circulating EV71 strains are limited. The objectives of this study were to determine the genotypes/subgenotypes and investigate the phylogeny of EV71 isolates in Dak Lak over a 6-year period. Viruses were isolated from clinical samples from patients with HFMD. In total, 43 EV71 isolates circulated in Dak Lak during 2011-2016 were used for the phylogenetic analysis using complete VP1 gene. The phylogenetic analysis of the VP1 gene revealed that two major genotypes, B and C, were found. Among the 43 EV71 strains, 29 belonged to subgenotype C4, 2 belonged to subgenotype C5, and 12 belonged to subgenotype B5. Of these, the subgenotype C4 was predominant in 2011-2013 and this was later replaced by the subgenotype B5 in 2014. The subgenotype B5 was dominant between 2014 and 2015, and then C4 recirculated in 2016. Our study also indicated that the subgenotypes C4 and B5 emerged into Dak Lak were closely related to variants causing epidemics of HFMD in the southern and central region of Vietnam and Thailand. Sequence analysis showed that nine amino acid mutations were detected in the VP1 region. Our results identified two significant amino acid substitutions (D31N and E145G/Q) associated with enhancing EV71 virulence.  相似文献   
957.
Cancer remains one of the most difficult and elusive disorders to prevent and treat, despite great efforts in research and treatment over the last 30 years. Researchers have tried to understand the pathogenesis of cancer by discovering the single cellular mechanism or pathway derived from a genetic mutation. There are limited efforts made toward discovering a unified concept of cancer. We propose a neuro-bioenergetic concept of cancer pathogenesis based on the central mechanism of cellular hyperexcitability via inducible overexpression of voltage-gated ion channels, ligand-gated channels and neurotransmitters. Exploration of this concept could lead to a better understanding of the cause of cancer as well as developing more effective and specific strategies toward cancer prevention and treatment.  相似文献   
958.
ackground: Human epidermal growth factor receptor 2 (HER2) plays an important role in the development and progression of breast cancer. To understand the precise association, this meta-analysis was conducted to estimate the association between HER2Ile655Val single nucleotide polymorphism (SNP) and susceptibility to early-onset breast cancer. Methods: A comprehensive database retrieval from PubMed, Embase, Web of Science and Google Scholar was pooled to investigate links between the HER2Ile655Val SNP and risk of breast cancer. Adjusted odds ratios (ORs) with 95% confidence intervals (CIs) were estimated to appraise the association under the additive model (Ile vs. Val), dominant model (Val/Val + Ile/Val vs. Ile/Ile), and recessive model (Val/Val vs. Ile/Val + Ile/Ile). Results: Seventeen relevant studies with 11,749 cases and 8,105 controls were finally included. We found that HER2Ile655Val SNP is associated with an increased risk of breast cancer in an additive and dominant model. In the subgroup analysis with age stratification, a significant association between the HER2 codon 655 SNP and the risk of breast cancer was found in young women in an additive, dominant, and recessive model; conversely, no significant associations were indicated in older women. In the breast cancer subgroup, HER2Ile655Val SNP was significantly associated with younger age women with breast cancer in the dominant model. In contrast, no association between the HER2 codon 655 SNP and age was found in control populations. Conclusion: Our findings suggest that the Val allele in HER2 codon 655 SNP is strongly associated with breast cancer susceptibility in the young female population and is also significantly associated with younger age in women with breast cancer. HER2Ile655Val SNP might be a susceptibility factor that favours early-onset breast cancer.  相似文献   
959.
Chemokine receptor 4 (CXCR4) and its ligand stromal-derived factor 1 (SDF-1) have well-characterized functions in cancer metastasis; however, the specific mechanisms through which CXCR4 promotes a metastatic and drug-resistant phenotype remain widely unknown. The aim of the present study was to demonstrate the application of a phenotypic screening approach using a small molecule inhibitor library to identify potential CXCR4-mediated signaling pathways. The present study demonstrated a new application of the Published Kinase Inhibitor Set (PKIS), a library of small molecule inhibitors from diverse chemotype series with varying levels of selectivity, in a phenotypic medium-throughput screen to identify potential mechanisms to pursue. Crystal violet staining and brightfield microscopy were employed to evaluate relative cell survival and changes to cell morphology in the screens. ‘Hits’ or lead active compounds in the first screen were PKIS inhibitors that reversed mesenchymal morphologies in CXCR4-activated breast cancer cells without the COOH-terminal domain (MCF-7-CXCR4-ΔCTD) and in the phenotypically mesenchymal triple-negative breast cancer cells (MDA-MB-231, BT-549 and MDA-MB-157), used as positive controls. In a following screen, the phenotypic and cell viability screen was used with a positive control that was both morphologically mesenchymal and had acquired fulvestrant resistance. Compounds within the same chemotype series were identified that exhibited biological activity in the screens, the ‘active’ inhibitors, were compared with inactive compounds. Relative kinase activity was obtained using published datasets to discover candidate kinase targets responsible for CXCR4 activity. MAP4K4 and MINK reversed both the mesenchymal and drug-resistant phenotypes, NEK9 and DYRK2 only reversed the mesenchymal morphology, and kinases, including ROS, LCK, HCK and LTK, altered the fulvestrant-resistant phenotype. Oligoarray experiments revealed pathways affected in CXCR4-activated cells, and these pathways were compared with the present screening approach to validate our screening tool. The oligoarray approach identified the integrin-mediated, ephrin B-related, RhoA, RAC1 and ErbB signaling pathways to be upregulated in MCF-7-CXCR4-ΔCTD cells, with ephrin B signaling also identified in the PKIS phenotypic screen. The present screening tool may be used to discover potential mechanisms of targeted signaling pathways in solid cancers.  相似文献   
960.
International Urology and Nephrology - The article “Interleukin 6 is&nbsp;a&nbsp;better predictor of&nbsp;5-year cardiovascular mortality than&nbsp;high-sensitivity C-reactive...  相似文献   
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