Alterations of plasma antioxidants and mitochondrial DNA mutation in hair follicles of smokers

The effects of long-term smoking on mitochondrial DNA (mtDNA) deletions in hair follicles were investigated in subjects with different antioxidant capacity. Twenty-two male smokers with a smoking index of greater than 5 pack-years and without any known systemic diseases were recruited for this study. Forty healthy nonsmoking males were included as controls. We found that the concentrations of ascorbate and alpha-tocopherol and the activities of glutathione S-transferase (GST) and glutathione peroxidase in blood plasma were significantly decreased in smokers. The levels of glutathione and protein thiols in whole blood and the incidence of a 4,977 bp deletion of mtDNA (dmtDNA) in hair follicles were significantly increased in smokers. A significantly higher incidence of the 4,977 bp dmtDNA was found in smokers with plasma GST activity less than 5.66 U/l (OR = 7.2, P = 0.020). Using multiple covariate ANOVA and logistic regression, we found that age and low plasma GST activity were the only two risk factors for the 4,977 bp dmtDNA. These results suggest that smoking depletes antioxidants and causes mtDNA deletions and that plasma GST may play an important role in the preservation of the mitochondrial genome in tissue cells of smokers.     

Distinct roles of pattern recognition receptors CD14 and Toll-like receptor 4 in acute lung injury

Acute lung injury (ALI) induced by lipopolysaccharide (LPS) is a major cause of mortality among humans. ALI is characterized by microvascular protein leakage, neutrophil influx, and expression of proinflammatory mediators, followed by severe lung damage. LPS binding to its receptors is the crucial step in the causation of these multistep events. LPS binding and signaling involves CD14 and Toll-like receptor 4 (TLR4). However, the relative contributions of CD14 and TLR4 in the induction of ALI and their therapeutic potentials are not clear in vivo. Therefore, the aim of the present study was to compare the roles of CD14 and TLR4 in LPS-induced ALI to determine which of these molecules is the more critical target for attenuating ALI in a mouse model. Our results show that CD14 and TLR4 are necessary for low-dose (300-microg/ml) LPS-induced microvascular leakage, NF-kappaB activation, neutrophil influx, cytokine and chemokine (KC, macrophage inflammatory protein 2, tumor necrosis factor alpha, interleukin-6) expression, and subsequent lung damage. On the other hand, when a 10-fold-higher dose of LPS (3 mg/ml) was used, these responses were only partially dependent on CD14 and they were totally dependent on TLR4. The CD14-independent LPS response was dependent on CD11b. A TLR4 blocking antibody abolished microvascular leakage, neutrophil accumulation, cytokine responses, and lung pathology with a low dose of LPS but only attenuated the responses with a high dose of LPS. These data are the first to demonstrate that LPS-induced CD14-dependent and -independent (CD11b-dependent) signaling pathways in the lung are entirely dependent on TLR4 and that blocking TLR4 might be beneficial in lung diseases caused by LPS from gram-negative pathogens.     

Multi-virulence-locus sequence typing clarifies epidemiology of recent listeriosis outbreaks in the United States

Multi-virulence-locus sequence typing (MVLST) was used to analyze isolates from two major listeriosis outbreaks in the United States in 1998 and 2002 that were due to consumption of contaminated hot dogs and turkey deli meat, respectively. MVLST demonstrated high epidemiological relevance and indicated that the two outbreaks were the result of one epidemic.     

应用肿瘤基因芯片筛选早期肺鳞癌相关基因

目的： 研究人早期肺鳞癌发生相关基因表达谱, 探讨肺鳞癌发生的分子机制。方法:选取人早期肺鳞癌组织以及相应正常组织，提取RNA, 与含480个与肿瘤相关基因的芯片杂交, 结果经SuperArray Image 软件分析后比较两种组织中的差异表达基因。结果:共筛查出差异表达基因192 条，其中表达上调基因127 条, 下调基因65条; 按照基因功能可分为运输载体、代谢相关基因、细胞信号转导分子、细胞骨架、转录调控因子基因。结论:基因芯片可用于早期肺鳞癌相关基因表达谱的筛查，可为明确早期肺鳞癌发生机制提供重要参考。     

移植物细胞因子表达与小肠移植排斥反应相关性的实验和临床病例研究

目的结合移植物细胞因子表达的实验和临床病例研究，探索早期诊断小肠移植急性排斥反应的细胞因子相关的敏感指标。方法①两例短肠综合症患者接受活体小肠移植术。定期或病情变化时随时行内镜组织学检查并测定受体大鼠移植物sIL-2R、IL-4、IL-6和IFN-γ表达水平。②BN-LEW大鼠部分小肠移植，A组：SBT（n=20）；B组：SBT＋FK506（2．5mg／kg，n=20），术后第1、4、7、14和30天测定受体大鼠移植物sIL-2R、IL-4、IL-6和IFN-γ水平同时取移植肠黏膜行病理组织学检查。结果首例术后67d发生排斥反应，第2例于术后20d和80d分别发生强烈排斥反应。发生排斥反应相应时相均发生IL-2Rα、IFN-γ表达的显著升高，排斥反应控制后IL-2Rα迅速恢复，但IFN-γ仍在较高水平维持较长时间。A组大鼠术后第1天始即显示IL-2Rα、IFN-γ和IL-6表达的显著升高，于术后7d达到最高，移植后14d仍在高水平。B组仅术后第1天出现IL-2Rα、IFN-γ和IL-6表达的迅速升高，第4天已恢复至基本正常。结论移植物IL-2Rα、IFN-γ表达的升高与小肠移植急性排斥反应密切相关，有望成为早期诊断小肠移植急性排斥反应的敏感指标。     

三氧化二砷对皮肤成纤维细胞、中性粒细胞MMPs活性,TIMP-1及TGF-β1表达的影响

目的：砒石是化腐生肌的常用中药，其主要成分是三氧化二砷（As₂O₃）。本研究通过观察As₂O₃对基质金属蛋白酶（MMPs）活性、基质金属蛋白酶组织抑制因子-1（TIMP-1）及转化生长因子β₁（TGF-β₁）表达影响，探讨化腐中药能否调节胶原代谢，从而治疗慢性皮肤溃疡。方法:明胶酶谱法检测大鼠中性粒细胞（PMNs）来源的MMP-9活性、人成纤维细胞（hFb）分泌的MMP-1、MMP-2的活性，免疫细胞化学法检测hFb TIMP-1、TGF-β₁的表达。结果:As₂O₃浓度在50 mg/L时可以提高大鼠PMNs来源的MMP-9的活性（P<0.01）；在0.8 mg/L可以提高hFb分泌的MMP-1、MMP-2的活性（分别P<0.01）；同时As₂O₃作用于hFb 6 h、12 h、18 h后，TIMP-1、TGF-β₁表达持续降低（P<0.01）。结论:As₂O₃在一定范围内可提高PMNs来源的MMP-9的活性；也可提高hFb分泌的MMP-1、MMP-2的活性，同时抑制hFbTIMP-1、TGF-β₁的表达。提示砷类制剂可通过提高多种MMPs的活性，降低TIMP-1的表达从而发挥化腐作用。     

Fast Dipstick Dye Immunoassay for Detection of Immunoglobulin G (IgG) and IgM Antibodies of Human Toxoplasmosis

A dipstick dye immunoassay (DDIA) was developed to detect immunoglobulin G (IgG) or IgM antibodies of toxoplasmosis infection in humans. The assays employ a blue colloidal dye particles (D-1) conjugated to sheep anti-human IgG and rabbit anti-human IgM as the visualizing agents and a soluble antigen of tachyzoites of Toxoplasma gondii strain RH (TSA) as the detective antigen. The mixture of dye-labeled anti-human antibody-special human antibody was captured by TSA onto a nitrocellulose membrane dipstick by means of immunochromatography. The assays are rapid (the whole test can be completed within 15 min), simple, and cheap, and they don't require any equipment. They are sensitive and specific for the detection of anti-Toxoplasma IgG or IgM antibodies and generally agree closely with the results from the enzyme-linked immunosorbent assay. The assays are especially suitable for field applications.     

Specific immunoglobulin g antibody detected in umbilical blood and amniotic fluid from a pregnant woman infected by the coronavirus associated with severe acute respiratory syndrome

Specific immunoglobulin G antibody for severe acute respiratory syndrome (SARS) coronavirus was detected in maternal blood, umbilical blood, and amniotic fluid from a pregnant SARS patient. Potential protection of fetus from infection was suggested.     

体外反搏对血液流变性和血小板聚集性的影响

观察４０例心脑血管疾病患者体外反搏前后血液流变性和血小板聚集性变化。结果表明，反搏后全血比及还原比粘度、血浆粘度有不同程度的下降（Ｐ＜０．０５～０．０１）。反搏治疗后，１～５ｍｉｎ血小板聚集率、最大聚集率和最大聚集速度较反搏前均明显降低（Ｐ＜０．０５～０．０１），而５ｍｉｎ解聚率则明显增加（Ｐ＜０．０５）。提示体外反搏治疗不仅影响血液动力学，而且明显降低血液粘度，对血小板聚集功能有明显抑制作用。