Nitric Oxide Modulates MCP-1 Expression in Endothelial Cells: Implications for the Pathogenesis of Pulmonary Granulomatous Vasculitis

Monocyte chemoattractant protein-1 (MCP-1) is a pivotal mediator of angiocentric granuloma formation in glucan-induced pulmonary granulomatous vasculitis. Based on the rationale that mononuclear phagocytes retrieved from granulomas are rich sources of nitric oxide (NO) and that the recruitment of mononuclear phagocytes into lesions abates as granuloma formation slows, we tested the hypothesis that MCP-1 gene expression is regulated by a NO-sensitive mechanism. Preexposure of endothelial cell (EC) monolayers to NO donor compounds markedly reduced cytokine-induced MCP-1 expression and cytosolic-to-nuclear translocation of nuclear factor-kappa B (NF-B), reversed fluctuations in endothelial reduced glutathione (GSH) pools but did not affect cGMP concentrations. The lungs of mice bearing targeted disruptions of the inducible nitric oxide synthase (iNOS) gene exhibited significantly higher concentrations of MCP-1 following glucan infusion than did those of wild-type mice. Cumulatively, these data suggest that NO suppresses MCP-1 expression by blunting the redox changes associated with cytokine-induced EC activation.     

Loss of LFA-1, but not Mac-1, protects MRL/MpJ-Fas(lpr) mice from autoimmune disease

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by immune complex-mediated tissue injury. Many different adhesion molecules are thought to participate in the development of SLE; however, few studies have directly examined the contributions of these proteins. Here we demonstrate that LFA-1 plays an essential role in the development of lupus in MRL/MpJ-Fas(lpr) mice. Mice deficient in LFA-1, but not Mac-1, showed significantly increased survival, decreased anti-DNA autoantibody formation, and reduced glomerulonephritis. The phenotype of the LFA-1-deficient mice was similar to that observed in beta(2) integrin-deficient (CD18-null) MRL/MpJ-Fas(lpr) mice, suggesting a lack of redundancy among the beta(2) integrin family members and other adhesion molecules. These studies identify LFA-1 as a key contributor in the pathogenesis of autoimmune disease in this model, and further suggest that therapeutic strategies targeting this adhesion molecule may be beneficial for the treatment of SLE.     

16例应激性溃疡的临床诊治体会

目的 报告应激性溃疡的临床诊治体会。方法 全组16例,男12例,女4例。术前均无溃疡病史,血红蛋白检查均正常。术后早期应用糖皮质激素9例,出血前发生肺不张、严重呼吸道感染、呼吸功能不全6例,低血容量休克5例,急性重症出血坏死性胰腺炎4例,食管癌、贲门癌术后6例,严重烧伤(80％(?)Ⅱ°)1例。14例保守治疗,2例保守治疗无效而手术治疗。结果14例经治疗后(2例手术治疗)痊愈出院,2例死亡。结论 应激性溃疡大出血患者多病情危重,难以忍受二次手术,死亡率约为50％,因此应采取有效的保守治疗,对于保守治疗无效、大出血休克或胃肠穿孔者应及时手术治疗。     

STAT3 couples with 14-3-3σ to regulate BCR signaling,B-cell differentiation,and IgE production

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慢性乙型肝炎肝内HBV DNA和HBsAg的双标记定位研究

应用原位杂交和免疫组化PAP法双标记技术,结合病人乙型肝炎(乙肝)病毒血清学标志物检测结果,研究了31例慢性乙肝病人肝穿刺组织中乙型肝炎病毒DNA(HBV DNA)和HBsAg的分布及意义。结果显示,肝组织内检出HBV DNA 23例,HBsAg 26例,二者同时检出者21例。从同组病人肝组织内HBV DNA和HBsAg双标检测结果与其乙肝病毒血清学标志物检测结果的比较来看,肝组织内HBV DNA和HBsAg同时阳性很可能表明HBV正处于复制及表达的活动状态。     

An optimal algorithm for configuring delivery options of a one-dimensional intensity-modulated beam

The problem of generating delivery options for one-dimensional intensity-modulated beams (1D IMBs) arises in intensity-modulated radiation therapy. In this paper, we present an algorithm with the optimal running time, based on the 'rightmost-preference' method, for generating all distinct delivery options for an arbitrary 1D IMB. The previously best known method for generating delivery options for a 1D IMB with N left leaf positions and N right leaf positions is a 'brute-force' solution, which first generates all N! possible combinations of the left and right leaf positions and then removes combinations that are not physically allowed delivery options. Compared with the brute-force method, our algorithm has several advantages: (1) our algorithm runs in an optimal time that is linearly proportional to the total number of distinct delivery options that it actually produces. Note that for a 1D IMB with multiple peaks, the total number of distinct delivery options in general tends to be considerably smaller than the worst case N!. (2) Our algorithm can be adapted to generating delivery options subject to additional constraints such as the 'minimum leaf separation' constraint. (3) Our algorithm can also be used to generate random subsets of delivery options; this feature is especially useful when the 1D IMBs in question have too many delivery options for a computer to store and process. The key idea of our method is that we impose an order on how left leaf positions should be paired with right leaf positions. Experiments indicated that our rightmost-preference algorithm runs dramatically faster than the brute-force algorithm. This implies that our algorithm can handle 1D IMBs whose sizes are substantially larger than those handled by the brute-force method. Applications of our algorithm in therapeutic techniques such as intensity-modulated arc therapy and 2D modulations are also discussed.     

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。     

Effect of Chlamydia pneumoniae on cellular ATP content in mouse macrophages: role of Toll-like receptor 2

Chlamydiae are obligate intracellular gram-negative bacteria and are dependent on the host cell for ATP. Thus, chlamydial infection may alter the intracellular levels of ATP and affect all energy-dependent processes within the cell. We have shown that both live C. pneumoniae and inactivated C. pneumoniae induce markers of cell death prior to completion of the bacterial growth cycle. As depletion of ATP could account for the observed increase in cell death, the effects of C. pneumoniae on ATP concentrations within mouse macrophages were investigated. Live, heat-killed, and UV-inactivated C. pneumoniae cultures (at multiplicities of infection [MOIs] of 0.01, 0.1, and 1.0) were incubated with mouse bone marrow macrophages isolated from C57BL/6J mice and mice deficient in Toll-like receptors. Treatment of the macrophages with both live and inactivated C. pneumoniae increased the ATP content of the cells. In cells infected with live C. pneumoniae, the increase was inversely proportional to the MOI. In cells treated with inactivated C. pneumoniae, the increase in ATP content was smaller than that induced by infection with live organisms and was proportional to the MOI. The increase in ATP content early in the developmental cycle was independent of the growth of C. pneumoniae, while sustained induction required live organisms. The capacity of C. pneumoniae to increase the ATP content was ablated in macrophages deficient in expression of either Toll-like receptor 2 or the Toll-like receptor accessory protein MyD88. In contrast, no effect was observed in macrophages lacking expression of Toll-like receptor 4.     

基于USB2.0的医用内窥镜超声探头旋转扫描成像系统

介绍基于USB2．0接口的医用超声内窥镜旋转扫描成像的设计与实现。根据超声成像的特点，本系统采取脉冲回波成像方式，文中介绍了超声波激发、接收电路以及收发隔离电路。针对旋转扫描的特点，设计了基于FPGA的同步控制电路和基于USB2．0接口的数据传输电路。对采集到的原始图像，进行坐标变换，获得了按直角坐标显示的灰度图像。利用连续旋转马达对实际物体扫描成像的实验结果，验证了系统的正确性。     

流感病毒血凝素基因工程抗体的抗病毒实验效果观察

目的：对昆虫细胞系统表达纯化的中和性流感病毒血凝素基因工程全抗体IgG-IV-2,IgG-IV-6进行体外和体内抗病毒效果的研究。方法：对比抗体应用前后病毒在MDCK细胞中的病毒滴度和动物模型中粘膜用药前后鼠肺内病毒滴度的改变，验证抗体的粘膜抗感染效果。结果：两株基因工程抗体使4．5log10TCID50滴度的病毒下降1／2的剂量分别为0．8μg和0．5μg；动物模型的粘膜给药表明使4．0log10TCID50的病毒下降1／2所需的抗体剂量IgG-IV-2为0．25mg/kg体重，IgG-IV-6为0．1mg/kg体重，联合应用时为0．08mg/kg体重。结论：获得的基因工程抗体具有体内体外的抗病毒效果，能够中和病毒毒力。