右房后壁双电位标测对判断房性心动过速起源点的参考价值

目的探讨右房后壁双电位标测对判断房性心动过速(简称房速)是否起源于左房的价值。方法选取19例成功行射频消融治疗的房速患者,房速起源点位于左房12例,位于右房7例,所有病例均在右房后壁记录到双电位。结果左房房速时,双电位的第一个成分振幅均明显低于第二个成分,且窦性心律时,同一部位记录的双电位顺序发生逆转,而右房房速时,第一个成分振幅均明显高于第二个成分,窦性心律时两电位的顺序不改变。结论通过右房后壁双电位标测,能快速而可靠地判断房速是否起源于左房。     

Blood cell, liver function, and response changes by PEG-interferon-α2b plus ribavirin with polaprezinc therapy in patients with chronic hepatitis C

Purpose Zinc has been reported to ameliorate hematologic side effects and improve liver function. In addition to its various effects, zinc supplementation in chronic hepatitis C patients with genotype 1b of high viral load enhanced the response to interferon (IFN) monotherapy. This study was aimed at clarifying whether zinc could improve hematologic side effects, improve liver function, and enhance the response to therapy in patients with chronic hepatitis C treated with pegylated-interferon (PEG-IFN) plus ribavirin (RBV). Methods The 32 patients enrolled in the study were randomly divided into two groups: a PEG-IFN-α2b plus RBV with zinc group (PEG/RBV + zinc, n = 16) and a PEG-IFN-α2b plus RBV group (PEG/RBV, n = 16). HCV-RNA, serum zinc, ALT, white blood cell, red blood cell, platelet, and hemoglobin (Hb) levels were examined. Results Serum zinc levels were significantly higher in the PEG/RBV with zinc group than in the PEG/RBV without zinc group at 4, 8, and 12 weeks. No significant differences were observed in the clearance of HCV-RNA between the two groups. The outcome of the treatment was similar; results of laboratory examinations including ALT before, during, and after therapy revealed no significant differences between the two groups at any point in all items except serum zinc levels. A sustained virological response rate was observed in 50.0% in the PEG/RBV with zinc group and 43.8% in the PEG/RBV without zinc group, with no significant difference between the two groups. Conclusions The study demonstrated no evidence that zinc ameliorates hematologic side effects, improves liver function, and enhances the response to the therapy in chronic hepatitis C receiving PEG-IFN-α2b plus RBV.     

原发性高血压患者脂餐后甘油三酯代谢异常与颈动脉内中膜复合体厚度的关系

为探讨原发性高血压患者是否存在脂肪负荷后血清富含甘油三酯脂蛋白代谢异常及其与颈动脉内中膜复合体厚度之间的关系 ,选择 38例原发性高血压患者和 30例健康人 (对照组 ) ,禁食 10～ 12h后 ,采用二维血管超声测定双侧颈动脉内中膜复合体厚度。随后进行标准脂肪负荷试验 ,分别以甘油三酯 8h曲线下面积和甘油三酯峰反应作为脂肪负荷后甘油三酯反应水平的指标。发现 :①原发性高血压组甘油三酯峰反应 (4.6 8± 1.74mmol L比 1.76± 0 .6 4mmol L)及甘油三酯曲线下面积 (2 3.5 9± 6 .4 8mmol L比 9.5 6± 3.38mmol L ,8h)显著大于对照组 (P<0 .0 5 ) ;②原发性高血压组颈动脉内中膜复合体厚度显著大于对照组 (0 .76 7± 0 .15mm比 0 .6 0 3± 0 .0 5mm ,P <0 .0 1) ;③原发性高血压患者的颈动脉内中膜复合体厚度与甘油三酯曲线下面积、年龄、甘油三酯峰反应、肥胖指数呈正相关 (r=0 .4 97、0 .4 4 8、0 .382、0 .35 2 ,P <0 .0 5 ) ,同空腹高密度脂蛋白水平呈负相关 (r =- 0 .2 87,P =0 .0 0 2 )。提示原发性高血压患者存在脂餐后甘油三酯代谢异常 ,高血压和餐后甘油三酯代谢异常均与颈动脉内中膜复合体厚度的增加有关。     

Detection of human papillomavirus in Chinese esophageal squamous cell carcinoma and its adjacent normal epithelium

AIM: To investigate the putative role of human papillomavirus (HPV) infection in the carcinogenesis of esophageal squamous cell carcinoma in China. METHODS: Twenty-three esophageal squamous cell carcinoma samples and the distal normal epithelium from Shanxi Province, and 25 more esophageal squamous cell carcinoma samples from Anyang city, two areas with a high incidence of esophageal cancer in China, were detected for the existence of HPV-16 DNA by PCR, mRNA in situ hybridization (ISH) and immunohistochemistry (IHC) targeting HPV-16 E6 gene. RESULTS: There were approximately 64 % (31/48) patients having HPV-16 DNA in tumor samples, among them nearly two-thirds (19/31) samples were detected with mRNA expression of HPV-16 E6. However, in the normal esophageal epithelium from cancer patients, the DNA and mRNA of HPV-16 were found with much less rate: 34.7 % (8/23) and 26.1 % (6/23) respectively. In addition, at protein level detected by IHC assay, 27.1 % (13/48) tumor samples had virus oncoprotein E6 expression, while only one case of normal epithelium was found positive. CONCLUSION: HPV infection, especially type 16, should be considered as a risk factor for esophageal malignancies in China.     

Crystal structure of murine cyclophilin C complexed with immunosuppressive drug cyclosporin A.

Cyclophilin is a cellular receptor for the immunosuppressive drug cyclosporin A (CsA). Cyclophilin C (CyPC) is highly expressed in murine kidney, making it a potential mediator of the nephrotoxic effects of CsA. The structure of murine CyPC complexed with CsA has been solved and refined to an R factor of 0.197 at a 1.64-A resolution. Superposition of the CyPC-CsA structure with the unligated cyclophilin A (CyPA) revealed significant migration of three loops: Gln-179 to Thr-189, Asp-47 to Lys-49, and Met-170 to Ile-176. The proximity of the loop Gln-179 to Thr-189 to the CsA binding site may account for the unique binding of a 77-kDa glycoprotein, CyPC binding protein (CyCAP), to CyPC. The binding of CsA to CyPC is similar to that of CsA to human T-cell cyclophilin A (CyPA). However, the conformation of CsA when bound to CyPC is significantly different from that when bound to CyPA. These differences may reflect conformational variation of CsA when bound to different proteins. Alternatively, the previous CyPA-CsA structure at low resolution may not provide sufficient details for a comparison with the CyPC-CsA structure.     

高糖和抗生素对大鼠腹膜间皮细胞表达PAI和TGF—βmRNA的影响

为探讨腹膜硬化的发生机制，采用腹膜间皮细胞培养、纤维蛋白平板方法和Ｎｏｒｔｈｅｒｎ杂交技术观察了不同浓度葡萄糖和抗生素庆大霉素与头孢唑啉钠对大鼠腹膜间皮细胞纤溶酶原激活物抑制物（ＰＡＩ）产生和转化生长因子－β（ＴＧＦ－β）ｍＲＮＡ表达的影响。结果表明腹膜间皮细胞可表达ＰＡＩ－１ｍＲＮＡ和产生活性ＰＡＩ；培养１２小时，１１．２ｍｍｏｌ／Ｌ的高渗葡萄糖、庆大霉素和头孢唑啉钠可增强腹膜间皮细胞ＰＡＩ－１ｍＲＮＡ的表达和增加活性ＰＡＩ的分泌；培养至２４小时，１１．２ｍｍｏｌ／Ｌ的高渗葡萄糖继续诱导腹膜间皮细胞产生活性ＰＡＩ增加，庆大霉素既可以继续引起ＰＡＩ－１ｍＲＮＡ表达增加，而且还可以使腹膜间皮细胞活性ＰＡＩ产生增加。同时在培养２４小时，１１．２ｍｍｏｌ／Ｌ的高渗葡萄糖和庆大霉素与头孢唑啉钠均可引起腹膜间皮细胞ＴＧＦ－βｍＲＮＡ表达增加。结果提示：１１．２ｍｍｏｌ／Ｌ的高渗葡萄糖和庆大霉素与头孢唑啉钠可以导致间皮细胞表达ＰＡＩ和ＴＧＦ－β上调，在腹膜硬化发生机制中起着重要作用。     

ROMK1 channel activity is regulated by monoubiquitination

The ubiquitination of proteins can signal their degradation, modify their activity or target them to specific membranes or cellular organelles. Here, we show that monoubiquitination regulates the plasma membrane abundance and function of the potassium channel, ROMK. Immunoprecipitation of proteins obtained from renal cortex and outer medulla with ROMK antibody revealed that this channel was monoubiquitinated. To determine the ubiquitin binding site on ROMK1, all intracellular lysine (Lys) residues of ROMK1 were individually mutated to arginine (Arg), and a two-electrode voltage clamp was used to measure the ROMK1 channel activity in Xenopus oocytes. ROMK1 channel activity increased from 8.1 to 27.2 microA only when Lys-22 was mutated to Arg. Furthermore, Western blotting failed to detect the ubiquitinated ROMK1 in oocytes injected with R1K22R. Patch-clamp experiments showed that biophysical properties of R1K22R were identical to those of wild-type ROMK1. Although total protein expression levels of GFP-ROMK1 and GFP-R1K22R in oocytes were similar, confocal microscopy showed that the surface fluorescence intensity in oocytes injected with GFP-R1K22R was higher than that of GFP-ROMK1. In addition, biotin labeling of ROMK1 and R1K22R proteins expressed in HEK293 cells showed increased surface expression of the Lys-22 mutant channel. Finally, expression of R1K22R in COS7 cells significantly stimulated the surface expression of ROMK1. We conclude that ROMK1 can be monoubiquitinated and that Lys-22 is an ubiquitin-binding site. Thus, monoubiquitination of ROMK1 regulates channel activity by reducing the surface expression of channel protein. This finding implicates the linking of a single ubiquitin molecule to channels as an important posttranslational regulatory signal.     

从博弈论角度探究医疗支付运用DRGs支付方式的有效性

当前医改的一块"硬骨头"是如何改进医疗支付方式。笔者从博弈论角度探究医院管理中现行医疗支付方式存在的问题,探讨DRGs支付方式的有效性分析DRGs将有助于打破当前医院管理的"纳什均衡",并有利于增进医院管理的效率与公平,是医院管理的一种有效探索。