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排序方式: 共有1959条查询结果,搜索用时 15 毫秒
961.
Baleeiro RB Anselmo LB Soares FA Pinto CA Ramos O Gross JL Haddad F Younes RN Tomiyoshi MY Bergami-Santos PC Barbuto JA 《Cancer immunology, immunotherapy : CII》2008,57(9):1335-1345
INTRODUCTION: Antigen-presenting cells, like dendritic cells (DCs) and macrophages, play a significant role in the induction of an immune response and an imbalance in the proportion of macrophages, immature and mature DCs within the tumor could affect significantly the immune response to cancer. DCs and macrophages can differentiate from monocytes, depending on the milieu, where cytokines, like interleukin (IL)-4 and granulocyte-macrophage colony-stimulating factor (GM-CSF) induce DC differentiation and tumor necrosis factor (TNF)-alpha induce DC maturation. Thus, the aim of this work was to analyze by immunohistochemistry the presence of DCs (S100+ or CD1a+), macrophages (CD68+), IL-4 and TNF-alpha within the microenvironment of primary lung carcinomas. RESULTS: Higher frequencies of both immature DCs and macrophages were detected in the tumor-affected lung, when compared to the non-affected lung. Also, TNF-alpha-positive cells were more frequent, while IL-4-positive cells were less frequent in neoplastic tissues. This decreased frequency of mature DCs within the tumor was further confirmed by the lower frequency of CD14-CD80+ cells in cell suspensions obtained from the same lung tissues analyzed by flow cytometry. CONCLUSION: These data are discussed and interpreted as the result of an environment that does not oppose monocyte differentiation into DCs, but that could impair DC maturation, thus affecting the induction of effective immune responses against the tumor. 相似文献
962.
963.
目的探讨TTF-1和HBME-1在肺癌患者胸水中的诊断价值。方法应用免疫细胞化学方法(S-P)研究51例原发性肺癌患者和10例继发性肺癌患者胸水中的癌细胞及44例肺良性疾病胸水中反应性间皮细胞的表达。结果TTF-1在原发性肺癌患者胸水中的阳性率为78.4%(40/51),而在继发性肺癌患者和肺良性疾病患者的胸水中未见阳性表达;HBME-1在肺良性疾病患者胸水中的阳性率95.5%(42/44)明显高于在原发性肺癌患者胸水中25.5%(13/51)和继发性肺癌患者胸水的阳性率20.0%(2/10);在不同病理类型原发性肺癌患者胸水中,TTF-1的阳性率在腺癌组90.7%(39/43)明显高于鳞癌组12.5%(1/8);当TTF-1和HBME-1联合应用时为最佳选择,其检测肺癌患者胸水的敏感性和特异性分别高达96.7%和95.5%。结论TTF-1和HBME-1对原发性、继发性肺癌患者胸水中癌细胞的诊断及鉴别诊断具有重要的临床应用价值。 相似文献
964.
To evaluate the joint effect of nine single nucleotide polymorphisms for three DNA repair genes in the region of chromosome 19q13.2-3 on susceptibility of lung cancer in a Chinese population, we conducted a hospital-based case–control study consisting of 247 lung cancer cases and 253 cancer-free controls matched on age, gender and ethnicity. Associations between the haplotypes and susceptibility of lung cancer were tested. The global test of haplotype association revealed a statistically significant difference in the haplotype distribution between cases and controls (global test: χ2 = 60.45, d.f. = 15, P = 2.11E−07). The two haplotypes were underrepresented among cases (Hap5 defined by ERCC1118A–ERCC2156C–ERCC2312G–ERCC2751A–XRCC1194T–XRCC1206A–XRCC1280G–XRCC1399G–XRCC1632G and Hap12 defined by ERCC1118G–ERCC2156C–ERCC2312G–ERCC2751A–XRCC1194C–XRCC1206A–XRCC1280G–XRCC1399A–XRCC1632G). Three of the haplotypes were overrepresented among cases (Hap3 defined by ERCC1118A–ERCC2156C–ERCC2312G–ERCC2751A–XRCC1194C–XRCC1206A–XRCC1280G–XRCC1399G–XRCC1632G, Hap4 defined by ERCC1118A–ERCC2156C–ERCC2312G–ERCC2751A–XRCC1194C–XRCC1206G–XRCC1280G–XRCC1399G–XRCC1632A, and Hap10 defined by ERCC1118G–ERCC2156A–ERCC2312G–ERCC2751A–XRCC1194T–XRCC1206A–XRCC1280G–XRCC1399G–XRCC1632G). Haplotypes 3 and 10 (cases = 5.7%, controls = 1.0%, OR = 6.56, 95%CI = 1.83–23.54, P = 0.001; cases = 13.3%, controls = 5.6%, OR = 2.73, 95%CI = 1.51–4.94, P = 0.0006) were the most strongly associated with increased lung cancer risk. There was considerable linkage disequilibrium exists between SNPs both within genes and between genes in the region. The two blocks for solid spine of LD and six htSNPs were found. The haplotype analysis suggested that the biologically effective polymorphisms co-segregate with some of the haplotypes. This result supports the hypothesis that the sub-region is important for lung cancer susceptibility. Haplotype studies using larger study groups will be required to obtain conclusive results. 相似文献
965.
Genotoxicity, cytotoxicity or teratogenicity are among the well-known detrimental effects of the volatile anaesthetics. The aim of the present work was to study the structural changes, proliferative activity and the possibility of alveolar A549 cells to recover after in vitro exposure to halothane at 1.5 and 2.1 mM concentrations. Our data indicated significant reduction of viability, suppression of mitotic activity more than 60%, and that these alterations were accompanied by disturbances of nuclear and nucleolar structures. The most prominent negative effect was the destruction of the lamellar bodies, the main storage organelles of pulmonary surfactant, substantial for the lung physiology. In conclusion, halothane applied at clinically relevant concentrations exerts genotoxic and cytotoxic effect on the alveolar cells in vitro, most likely as a consequence of stress-induced apoptosis, thus modulating the respiratory function. 相似文献
966.
Brendan J. R. Whittle va Morschl Jzsef Pozsr Anthony P. Moran Ferenc Lszl 《Journal of Physiology》2001,95(1-6)
We have examined the effects of intravenous administration of a purified lipopolysaccharide (LPS) from Helicobacter pylori (3 mg kg−1, i.v.) on rat vascular permeability, assessed by the radiolabelled human serum albumin leakage technique in the heart, kidney, liver and lung 4 h after challenge. An increased vascular permeability in cardiac, renal, hepatic and pulmonary tissues after challenge was determined. The albumin leakage observed in all these organs could be prevented by the selective inducible nitric oxide synthase inhibitor, N-(8-(aminomethyl)benzyl)-acetamidine (1400W; 0.2–1 mg kg−1, s.c.) administered concurrently with LPS. Thus, H. pylori LPS can provoke a microvascular inflammatory response in the rat cardiac, renal, hepatic and pulmonary tissues, actions mediated through the activation of the inducible nitric oxide synhase isoenzyme. 相似文献
967.
Several recent studies have demonstrated localization of donor bone marrow-derived cells in recipient lungs following transplantation from male to female mice or patients. Donor cells are identified by detection of the Y chromosome by fluorescence in situ hybridization (FISH). However, protein digestion pretreatments usually required for tissue FISH significantly limit the ability to detect cell type-specific markers by immunohistochemistry. We have used an alternative protein digest approach that entails heating the slides in 10 mM sodium citrate rather than utilizing a protease digestion. This approach preserves cell proteins following FISH, and allows lung tissue to remain intact for subsequent detection of cell-specific markers by immunohistochemistry. We have examined this technique in mouse lungs using a Y chromosome paint and three cell-specific markers, a pan-cytokeratin for epithelial cells, PECAM-1 for endothelial cells, and CD45 for leukocytes. Excellent visualization of both the Y chromosome and cell-specific surface protein markers was obtained on a single slide. This approach will significantly enhance the ability to detect and identify donor bone marrow cells in recipient mouse lungs following male to female transplantation. 相似文献
968.
Jung M Grunberg S Timblin C Buder-Hoffman S Vacek P Taatjes DJ Mossman BT 《Histochemistry and cell biology》2004,121(2):115-121
Concurrent administration of paclitaxel and vinorelbine results in cytotoxicity in vivo and in vitro in a number of tumor cell lines, yet the mechanisms of enhanced cell killing are undefined. In studies here, we show that low concentrations (1 nM) of paclitaxel and vinorelbine in combination result in enhanced cell killing by apoptosis (P<0.05) in the human lung adenocarcinoma cell line, A-549. In contrast, necrotic cell death and formation of multinucleated cells, which were significantly increased by paclitaxel (P<0.05) alone, but not vinorelbine, were not increased synergistically by both drugs. Paclitaxel also caused microtubular disruption which was not observed with vinorelbine. These data provide further rationale for the combined use of paclitaxel and vinorelbine in clinical trials, and suggest that the cooperative effects of drugs on apoptosis are not mediated through similar disruptional effects on microtubules. 相似文献
969.
Projections of lung cancer mortality in West Germany: a case study in Bayesian prediction 总被引:1,自引:0,他引:1
We apply a generalized Bayesian age-period-cohort (APC) model to a data-set on lung cancer mortality in West Germany, in the period 1952-1996. Our goal is to predict future death rates until the year 2010, separately for males and females. Since age and period are not measured on the same grid, we propose a generalized APC model where consecutive cohort parameters represent strongly overlapping birth cohorts. This approach results in a rather large number of parameters, where standard algorithms for statistical inference by Markov chain Monte Carlo methods turn out to be computationally intensive. We propose a more efficient implementation based on ideas of block sampling from the time series literature. We entertain two different formulations, penalizing either first or second differences of age, period and cohort parameters. To assess the predictive quality of both formulations, we first forecast the rates for the period 1987-1996 based on data until 1986. A comparison with the actual observed rates is made based on a predictive deviance criterion. Predictions of lung cancer mortality until 2010 are then reported and a modification of the formulation in order to include information on cigarette consumption is finally described.To whom correspondence should be addressed. Currently at Imperial College School of Medicine, Department of Epidemiology and Public Health, Norfolk Place, London W2 1PG, UK. 相似文献
970.
Narayanan K Krishnamoorthy B Ezhilarasan R Miyamoto S Balakrishnan A 《Cell biology international》2003,27(4):375-382
Tropical pulmonary eosinophilia (TPE) is an occult manifestation of filariasis, brought about by helminth parasites Wuchereria bancrofti and Brugia malayi. Treatment of patients suffering from TPE involves the administration of diethyl carbamazine and Ivermectin. Although the drugs are able to block acute inflammation, they are not able to alleviate chronic basal inflammation. We have attempted to examine the disease by targeting two important components; namely filarial parasitic sheath proteins (FPP) induced apoptosis and pro-inflammatory cytokine response in human laryngeal carcinoma cells of epithelial origin (HEp-2) cells an epithelial cell line. Earlier studies by us have shown that FPP exposure induced apoptosis in these cells. In this study with hydrocortisone, calpain inhibitor (ALLN) and phorbol myristate acetate (PMA) treatments we demonstrate that apoptosis is inhibited as shown by [3H] thymidine incorporation studies, propidium iodide staining and Annexin V staining. Hydrocortisone at a dose, which inhibits cell death also down regulated, the expression of pro-inflammatory cytokines IL-6 and IL-8. These findings give us insights into the multifaceted approach one may adopt to target critical signalling molecules using appropriate inhibitors, which could eventually be used to reduce lung damage in TPE. 相似文献