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991.
Activation of p38 mitogen-activated protein kinase contributes to the early cardiodepressant action of tumor necrosis factor. 总被引:1,自引:0,他引:1
Mohamed Bellahcene Sebastien Jacquet Xue B Cao Masaya Tanno Robert S Haworth Joanne Layland Alamgir M Kabir Matthias Gaestel Roger J Davis Richard A Flavell Ajay M Shah Metin Avkiran Michael S Marber 《Journal of the American College of Cardiology》2006,48(3):545-555
OBJECTIVES: The purpose of this study was to determine whether p38 mitogen-activated protein kinase (p38-MAPK) contributes to tumor necrosis factor-alpha (TNFalpha)-induced contractile depression. BACKGROUND: Tumor necrosis factor has both beneficial and detrimental consequences that may result from the activation of different downstream pathways. Tumor necrosis factor activates p38-MAPK, a stress-responsive kinase implicated in contractile depression and cardiac injury. METHODS: In isolated hearts from mice lacking the p38-MAPK activator, MAPK kinase 3 (MKK3), perfused at constant coronary pressure or flow, we measured the left ventricular developed pressure (LVDP) and the relationship between end-diastolic volume and LVDP in the presence and absence of 10 ng/ml TNFalpha. RESULTS: Within 15 min at constant pressure, TNFalpha significantly reduced LVDP and coronary flow in outbred and mkk3(+/+) mice. This early negative inotropic effect was associated with a marked phosphorylation of both p38-MAPK and its indirect substrate, HSP27. In hearts lacking MKK3, TNFalpha failed to activate p38-MAPK or to cause significant contractile dysfunction. The actions of TNFalpha were similarly attenuated in MAPK-activated protein kinase 2 (MK2)-deficient hearts, which have a marked reduction in myocardial p38-MAPK protein content, and by the p38-MAPK catalytic site inhibitor SB203580 (1 micromol/l). Under conditions of constant coronary flow, the p38-MAPK activation and contractile depression induced by TNFalpha, though attenuated, remained sensitive to the absence of MKK3 or the presence of SB203580. The role of p38-MAPK in TNFalpha-induced contractile depression was confirmed in isolated murine cardiac myocytes exposed to SB203580 or lacking MKK3. CONCLUSIONS: Tumor necrosis factor activates p38-MAPK in the intact heart and in isolated cardiac myocytes through MKK3. This activation likely contributes to the early cardiodepressant action of TNFalpha. 相似文献
992.
An anti-CD45RO immunotoxin kills latently infected human immunodeficiency virus (HIV) CD4 T cells in the blood of HIV-positive persons. 总被引:2,自引:0,他引:2
Jesús Saavedra-Lozano Cynthia McCoig Jinbo Xu Yanying Cao Philip Keiser Victor Ghetie Robert F Siliciano Janet D Siliciano Louis J Picker Octavio Ramilo Ellen S Vitetta 《The Journal of infectious diseases》2002,185(3):306-314
Highly active antiretroviral therapy has decreased the morbidity and mortality of human immunodeficiency virus (HIV) infection, but latently infected cells remain for prolonged periods. CD4(+) CD45RO(+) T cells are a major latent virus reservoir in HIV-infected persons. Replication-competent, latently HIV-infected T cells can be generated in vitro by infecting peripheral blood mononuclear cells with HIV and then eliminating the HIV-producing cells with an anti-CD25 immunotoxin (IT). The CD25(-) latently infected cells then can be eliminated with an anti-CD45RO IT. This study determined whether this IT also could kill latently infected CD4 T cells from HIV-infected persons with or without detectable plasma viremia. The results show that ex vivo treatment of cells from HIV-positive persons by anti-CD45RO IT reduces the frequency of both productively and latently infected cells. In contrast, CD4(+) CD45RA(+) naive T cells and a proportion of CD4(+) CD45RO(lo) memory T cells are spared. 相似文献
993.
Effect of antituberculosis drug resistance on response to treatment and outcome in adults with tuberculous meningitis 总被引:5,自引:0,他引:5
Thwaites GE Lan NT Dung NH Quy HT Oanh DT Thoa NT Hien NQ Thuc NT Hai NN Bang ND Lan NN Duc NH Tuan VN Hiep CH Chau TT Mai PP Dung NT Stepniewska K White NJ Hien TT Farrar JJ 《The Journal of infectious diseases》2005,192(1):79-88
BACKGROUND: Tuberculous meningitis (TBM) caused by Mycobacterium tuberculosis resistant to 1 or more antituberculosis drugs is an increasingly common clinical problem, although the impact on outcome is uncertain. METHODS: We performed a prospective study of 180 Vietnamese adults admitted consecutively for TBM. M. tuberculosis was cultured from the cerebrospinal fluid (CSF) of all patients and was tested for susceptibility to first-line antituberculosis drugs. Presenting clinical features, time to CSF bacterial clearance, clinical response to treatment, and 9-month morbidity and mortality were compared between adults infected with susceptible and those infected with drug-resistant organisms. RESULTS: Of 180 isolates, 72 (40.0%) were resistant to at least 1 antituberculosis drug, and 10 (5.6%) were resistant to at least isoniazid and rifampicin. Isoniazid and/or streptomycin resistance was associated with slower CSF bacterial clearance but not with any differences in clinical response or outcome. Combined isoniazid and rifampicin resistance was strongly predictive of death (relative risk of death, 11.63 [95% confidence interval, 5.21-26.32]) and was independently associated with human immunodeficiency virus infection. CONCLUSIONS: Isoniazid and/or streptomycin resistance probably has no detrimental effect on the outcome of TBM when patients are treated with first-line antituberculosis drugs, but combined isoniazid and rifampicin resistance is strongly predictive of death. 相似文献
994.
Xiaolin Wang Yushan Liu Guangxin Cao Xueliang Zhang Haifei Xu Hanfeng Xu Jiandong Wang 《International journal of clinical and experimental pathology》2015,8(6):6821-6827
Aberrant expression of receptor tyrosine kinase EphA1 in malignant tissues has been reported. However, the expression profile of EphA1 in renal cell carcinoma (RCC) and its association with clinicopathological parameters remain unknown. The aim of this study was to determine the cancerous value of the EphA1 protein expression in patients with renal cell carcinomas. This study included 144 patients with clear cell RCC (ccRCC), 18 patients with chromophobe RCC and 6 patients with papillary RCC. The EphA1 protein was detected in RCC tissue samples by an immunohistochemical staining with a specific polycolonal antibody. The correlation of the expression of the EphA1 protein with clinicopathological parameters was evaluated. High level of the expression of EphA1 was observed in all normal renal tubes. The EphA1 protein was negatively or weakly expressed in 93 out of 144 ccRCC (64.6%) and positively expressed in 51 out of 144 ccRCC (35.4%). The high level expression of the EphA1 protein was significantly associated with younger patients (P<0.001), sex (P=0.016) and lower nuclear grade (P<0.001). No significant relation between the expression of EphA1 and tumor diameter was found (P=0.316). Positive expression of EphA1 was observed in all samples of chromophobe RCC and papillary RCC. Our data indicated that the EphA1 protein may be a new marker for the prognosis of ccRCC. 相似文献
995.
Qian Yang Rui-Xing Yin Xiao-Li Cao Dong-Feng Wu Wu-Xian Chen Yi-Jiang Zhou 《International journal of clinical and experimental pathology》2015,8(6):7318-7331
Little is known about the association of the FADS1/FADS2 SNPs and serum lipid levels and the risk of coronary artery disease (CAD) and ischemic stroke (IS) in the Chinese southern population. The present study aimed to determine such association in the Chinese southern population. A total of 1,669 unrelated subjects (CAD, 534; IS, 553; and healthy controls, 582) were recruited in the study. Genotypes of the FADS1 rs174546 SNP and the FADS2 rs174601 SNP were determined by the SNaPshot Multiplex Kit. The T allele and TT genotype frequencies of the two SNPs were predominant in our study population. The T alleles were associated with increased risk of CAD and IS. Correspondingly, the C alleles were associated with reduced risk of CAD and IS. Haplotype analyses showed that the haplotype of T-T (rs174546-rs174601) was associated with an increased risk for IS, and the haplotype of C-C (rs174546-rs174601) was associated with a reduced risk for CAD and IS. The two SNPs were likely to influence serum lipid levels. The T allele carriers of the two SNPs and rs174601 TT genotype were associated with decreased serum HDL-C and ApoAI levels in the patient groups and with an increased risk of CAD and IS. The present study suggests that the FADS1 rs174546 SNP and the FADS2 rs174601 SNP are associated with the risk of CAD and IS, and are likely to influence serum lipid levels. However, further functional studies are needed to clarify how the two SNPs actually affect serum lipid levels and the risk of CAD and IS. 相似文献
996.
Weijuan Cai Liang Yin Jiang Cheng Shaoliang Wang Yu Wei Wenjiang Cao Jiang Cheng 《International journal of clinical and experimental pathology》2015,8(7):8358-8366
Objective: To study the correlation of β2-AR gene 5’-regulatory region SNPs and essential hypertension (EH) in Chinese Kazakh ethnic minority group. Methods: The Sequenom MassArray® SNP detection technology was used to detect β2-AR gene 5’-regulatory region SNPs in 150 Xinjiang Kazakh EH patients and 150 controls. Biochemical analyzer was used to detect lipid and other related biochemical parameters. SHEsis and other software were used to analyze linkage disequilibrium and haplotype. Results: Six loci rs205304 (-1023G/A), rs17108803 (-893T/G), rs12654778 (-654G/A), rs11168070 (-468C/G), rs11959427 (-367C/T) and rs2895795 (-1429T/A) polymorphisms of β2-AR gene 5’-regulatory region were found in the Xinjiang Kazakh populations. While, there was no significant difference between EH group and NH in genotypes and allele frequency of rs2053044, rs12654778, rs2895795, rs17108803 and rs11959427 (P>0.05). However; significant differences were detected of rs11168070 genotypes and allele frequency in two groups (P<0.05). Analysis of the linkage disequilibrium and haplotype in Kazakh population, there is a strong linkage disequilibrium of rs11168070, rs2053044, rs2895795 gene polymorphism in the EH group, and rs11168070, rs12654778, rs17108803 gene polymorphism in controls. Frequency of haplotype GTCCAT, GACTGT and ATGCGT in EH group was higher (P<0.05), while frequency of ATCTGT, ATGTGT, GTCCGT, GTCTAT, GACCAT and GTCTGT in the EH group was significantly lower than the control (P<0.05). Conclusions: β2-AR gene 5’-regulatory region of rs11168070, rs2053044, rs17108803, rs12654778, rs11959427 and rs2895795 genetic polymorphism exists in Kazakh. Among them, rs11168070 locus genotype and allele frequency distribution in the two groups are significant differences. In six polymorphic loci, there is a strong linkage disequilibrium, which haplotypes GTCCAT, GACTGT, ATGCGT are risk factors of EH, and the ATCTGT, ATGTGT, GTCCGT, GTCTAT, GACCAT, GTCTGT are protective factors. 相似文献
997.
Yanxia Wang Xin Huo Zheng Cao Hui Xu Jian Zhu Li Qian Hong Fu Bing Xu 《International journal of clinical and experimental pathology》2015,8(7):8099-8106
Hepatocellular carcinoma (HCC) is the most common primary liver tumor. Due to the asymptomatic nature of early HCC and lack of effective screening strategies, 80% of patients present with advanced HCC at the time of diagnosis. Novel molecular marker identification will be valuable for effective diagnosis and treatment. In this study we reported HCLS1-associated protein X-1 (HAX-1) is overexpression in HCC in human HCC sample. Furthermore, we provided evidence that HAX-1 expression positively correlated with that of Ki67 in patient sample. Statistic analysis indicated that HAX-1 expression level significantly correlated with clinic outcome of HCC. Cell based assay revealed that knockdown of HAX-1 inhibits cell proliferation. This result suggests that HAX-1 can be a novel molecular marker for HCC. 相似文献
998.
Jianbin Yang Dongyi Wei Weixin Wang Baohong Shen Suling Xu Yuan Cao 《International journal of clinical and experimental pathology》2015,8(9):11837-11846
Oral squamous cell carcinoma (OSCC) ranks as the fifth most common cancer worldwide with poor prognosis. Recently, tumor necrosis factor receptor-associated factor 4 (TRAF4) has attracted increasing attenuation due to its overexpression in certain cancers. However, its function and underlying mechanism in OSCC remains elusive. In this study, the high expression of TRAF4 mRNA and protein levels was noted in OSCC cell lines. Its overexpression with pcDNA3.1-TRAF4 vector transfection dramatically promoted cell proliferation and inhibited cell apoptosis, indicating a pivotal role of TRAF4 in OSCC cell growth. Simultaneously, TRAF4 elevation also increased cell invasion and migration. Mechanism analysis confirmed that TRAF4 up-regulation induced the expression of β-catenin and the downstream target molecules of cyclinD1, c-myc, Bcl-2, MMP-9 and MMP-2, indicating that TRAF4 could induce the activation of Wnt/β-catenin pathway. After pretreatment with β-catenin siRNA, the pathway was remarkably silenced. Simultaneously, cell growth, invasion and migration induced by TRAF4 were strikingly abrogated, suggesting that TRAF4 may promote OSCC cell growth, invasion and migration by Wnt/β-catenin pathway. Together, this study confirmed that TRAF4 acts as an oncogene for the development and progression of OSCC. Therefore, our study may support a promising therapeutic target for the treatment of OSCC. 相似文献
999.
Bo Yang Hua Zhao Bin X Ya-Bin Wang Jian Zhang Yu-Kang Cao Qing Wu Feng Cao 《International journal of clinical and experimental pathology》2015,8(11):13806-13813
In this study, by using vivo and vitro model, we assessed whether interleukin (IL)-1beta gene polymorphisms influence on the risk of myocardial infarction and ischemic stroke at young age. 147 patients (age < 45 years) with a first episode of MI and 56 patients (age < 45 years) with first-ever cerebral ischemia consecutively were admitted to this study from the Department of Chinese PLA General Hospital. Meanwhile, 91 normal volunteers without MI or stroke were deeded as control group and greed to give blood samples for DNA analysis and biochemical measurements by written informed consent. IL-1β-511 wild type (WT, CC) and SNP (TT) were established and transfected into Rat myocardial H9c2 cell and Mouse brain endothelial bEND.3 cells. In Young Age MI or stroke patients, the IL-1β levels of patients with 511CC are higher than that of patients with 511TT. In our study, NF-κB miRNA, iNOS activity, NF-κB, iNOS and Bax protein expressions of MI-induced H9c2 cell or stroke-induced bEND.3 cells in IL-1β-511TT group were lower than those of IL-1β-511CC. Additionally, the protein expression of MMP-2 of MI-induced H9c2 cell or stroke-induced bEND.3 cells in IL-1β-511TT group were higher than that of IL-1β 511CC group. In conclusion, our data indicate that IL-1β-511TT/CC influence on the risk of myocardial infarction and ischemic stroke at young age through NF-κB, iNOS, MMP-2 and Bax. 相似文献
1000.
Chi Zhang Xiang Hu Xiao-Yu Liu Pin Liang Jian Zhang Liang Cao Zheng-Lin Wang Huan-Ran Liu Xun-Guo Yin Cheng-Yong Dong Li-Ming Wang 《International journal of clinical and experimental pathology》2015,8(11):13795-13805
We observed whether the effect of tumor-associated macrophages on gastric cancer stem cell in omental milky spots and lymph nodes micrometastasis and research its possible mechanism. Macrophage THP-1 cells and Human gastric adenocarcinoma SGC-7901 cells were collectively cultivated in vivo. We found macrophage could suppress the proliferation and accelerated cell death of MFC cell. Meanwhile, these effects may be concerned with many signaling pathways, and we detected MCP-1 and COX-2 miRNA expressions, PGE-2 release levels, IL-4 and IL-10 activities, and TGF-β, IFN-γ, VEGF, MMP-2 and MMP-9 protein expressions in collectively cultivated cell. We found that MCP-1 and COX-2 miRNA expressions, and PGE-2 release levels were suppressed, IL-4 activity was inhibited and IL-10 activity was activated in collectively cultivated cell. Meanwhile, TGF-β, MMP-2 and MMP-9 protein expressions were inhibited and IFN-γ and VEGF protein expressions were activated in collectively cultivated cell. Taken together, these results suggest that the effect of tumor-associated macrophages on gastric cancer stem cell in omental milky spots and lymph nodes micrometastasis via COX-2/PGE-2/TGF-β/VEGF signal pathways. 相似文献