Endophilin isoforms have distinct characteristics in interactions with N-type Ca2+ channels and dynamin I

Objective Formation of the endophilin II-Ca 2+ channel complex is Ca 2+ -dependent in clathrin-mediated endocytosis. However, little is known about whether the other two endophilin isoforms have the same features. The present study aimed to investigate the characteristics of the interactions of all three isoforms with Ca 2+ channels and dynamin I. Methods N-type Ca 2+ channel C-terminal fragments (NCFs) synthesized with a 3 H-leucine-labeled kit, were incubated with endophilin-GST fusion proteins, followed by pull-down assay. Results were counted on a scintillation counter. In addition, the different endophilin isoforms were each co-transfected with dynamin I into 293T cells, followed by flow cytometry and co-immunoprecipitation assay. Immunostaining was performed and an image analysis program was used to evaluate the overlap coefficient of cells expressing endophilin and dynamin I. Results All three isoforms interacted with NCF. Endophilins I and II demonstrated clear Ca 2+ -dependent interactions with NCF, whereas endophilin III did not. Co-immunoprecipitation showed that, compared to endophilin I/II, the interaction between endophilin III and dynamin I was significantly increased. Similar results were obtained from flow cytometry. Furthermore, endophilin III had a higher overlap coefficient with dynamin I in co-transfected 293T cells. Conclusion Endophilin isoforms have distinct characteristics in interactions with NCF and dynamin I. Endophilin III binding to NCF is Ca 2+ -independent, implying that it plays a different role in clathrin-mediated endocytosis.     

进展期SARS与巨细胞病毒肺部感染的影像学研究

目的 :初步探讨严重急性呼吸综合征 (SARS)和巨细胞病毒 (CMV)肺部感染的影像特征及其病变进展规律。方法 :我院确诊SARS组 3 0例 ,CMV组并发成人呼吸窘迫综合征 (ARDS)者 14例 ,均动态追踪胸部平片检查 ,各 1例行CT检查。结果 :SARS在出现发热症状后 ,一般在 2、3天内迅速出现双肺中下肺野多发片状影。 6例出现ARDS ,表现为病灶迅速发展或部分吸收后又重新加重 ,无明确的游走发展趋势 ,1周左右进展为肺水肿。 5例轻症患者仅累及单肺叶或肺段 ,最早在第 3天有好转。 3例出现少量胸腔积液 ,而 2例在治疗中出现少量气胸 ,处理后好转。CMV组病变的ARDS进程类似 ,首先双肺纹理增粗、模糊 ,然后双肺中外带多发小片状影 ,7天内融合成实变的大片状影 ,10例死亡患者表现为肺水肿 ,呈磨玻璃样胸片改变。结论 :SARS冠状病毒直接侵犯肺泡上皮细胞 ,巨细胞病毒在成纤维细胞生长 ,均导致肺泡通透性增加 ,形成透明膜样改变 ,可导致肺水肿、实变。胸部影像多为肺纹理增多、模糊 ,演变成多发的肺叶渗出病灶 ,进展迅速 ,可全肺实变 ,但一般不破坏肺泡空间结构形成空洞。二者影像征象无明显差异。     

公立医院规模持续恶性扩张机制——“一环、两流、三切点”理论模型构建

以“构成要素～要素间的作用关系～结果”为机制研究框架,运用规模经济理论和交易成本理论,结合医疗服务特征,确定了医疗生产技术、医院规模、专科细化程度、市场规模和成本转嫁能力作为医院规模持续扩张五要素,分析了五要素间的相互作用和制约关系,构建了“规模扩张均衡环,医院收益流和成本流,医疗生产技术、市场规模和成本转嫁能力三要素切入点”的医院规模持续恶性扩张机制的理论模型,简称“一环、二流、三切点”模型。运用该模型,可解释我国转型期公立医院规模持续恶性扩张的管理体制和运行机制的制度性因素,为规模持续扩张调控策略和政策制定提供思考路径。     

Clinical significance of CA19-9 in diagnosis of digestive tract tumors

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Meta-Analysis of the Adverse Effects of Long-Term Azithromycin Use in Patients with Chronic Lung Diseases

The adverse effects of azithromycin on the treatment of patients with chronic lung diseases (CLD) were evaluated in the present study. MEDLINE and other databases were searched for relevant articles published until August 2013. Randomized controlled trials that enrolled patients with chronic lung diseases who received long-term azithromycin treatment were selected, and data on microbiological studies and azithromycin-related adverse events were abstracted from articles and analyzed. Six studies were included in the meta-analysis. The risk of bacterial resistance in patients receiving long-term azithromycin treatment was increased 2.7-fold (risk ratio [RR], 2.69 [95% confidence interval {95% CI}, 1.249, 5.211]) compared with the risk in patients receiving placebo treatment. On the other hand, the risk of bacterial colonization decreased in patients receiving azithromycin treatment (RR, 0.551 [95% CI, 0.460, 0.658]). Patients receiving long-term azithromycin therapy were at risk of increased impairment of hearing (RR, 1.168 [95% CI, 1.030, 1.325]). This analysis provides evidence supporting the idea that bacterial resistance can develop with long-term azithromycin treatment. Besides the increasingly recognized anti-inflammatory role of azithromycin used in treating chronic lung diseases, we should be aware of the potential for adverse events with its long-term use.     

Toll-like receptors mediate induction of peptidoglycan recognition proteins in human corneal epithelial cells

Human peptidoglycan recognition proteins (PGLYRPs) are a novel family of pattern recognition receptors, and also act as anti-bacterial proteins. This study was to explore the toll-like receptor (TLR)-mediated regulation of PGLYRPs in human corneal epithelial cells (HCECs). Fresh human donor corneoscleral tissues were used to prepare cryosections. Primary HCECs, established from limbal explants, were treated with microbial ligands to TLRs 1-9 for 4-48 h, with or without pretreatment of TLR antibodies, NFkB inhibitor, or siRNA transfection. The mRNA of PGLYRPs was evaluated by RT and real-time PCR, and their proteins and NFkB activation were determined by immunostaining and Western blot. The nuclear IRF3 activity was quantified using an ELISA-based TransAM kit. PGLYRP-2, -3 and -4 were found to be expressed by human corneal epithelium while PGLYRP-1 was not detected. In primary HCEC cultures, PGLYRP-3 and -4 were constitutively expressed while PGLYRP-2 was largely inducible. PGLYRP-2 was induced by bacterial components, Pam3CSK4, PGN, flagellin and FSL-1, ligands for TLR2/1, 2, 5 and 2/6, respectively. Interestingly, PGLYRP-2 was strongest stimulated by polyI:C representing viral dsRNA. TLR3 antibody or NFkB inhibitor blocked IRF3 and NFkB p65 activation as well as polyI:C-stimulated PGLYRP-2. RNA interference indicates that the polyI:C-induced PGLYRP-2 was dramatically blocked in the cells transfected with siRNA-TRIF but neither siRNA-MyD88 nor the negative control siRNA-F. These findings suggest that human corneal epithelium may response to viral or bacterial infection by producing PGLYRPs through TLRs, and the induction of PGLYRP-2 by dsRNA was through TLR3-TRIF-IRF3-NFkB signaling pathways.     

Perioperative Chemotherapy With or Without Bevacizumab in Patients With Metastatic Colorectal Cancer Undergoing Liver Resection

BackgroundPatients with colorectal cancer (CRC) and liver metastases benefit from perioperative chemotherapy and liver resection. The potential benefit of adding bevacizumab is yet to be defined. The impact of bevacizumab on liver resection complications has been explored in a small number of retrospective studies.MethodsThe records of patients with CRC and liver metastases who underwent liver resection and had received perioperative chemotherapy were reviewed. Complications were reported separately for 2 groups (chemotherapy alone vs chemotherapy and bevacizumab). Survival outcomes (progression-free survival [PFS] and overall survival [OS]) for responders and nonresponders were estimated using the Kaplan-Meier method.ResultsFifty-two patients received chemotherapy alone and 42 patients received chemotherapy and bevacizumab. The median time from the end of systemic treatment to liver resection was 59 days (33-181 days) for the chemotherapy group and 62 days (44-127 days) for the chemotherapy and bevacizumab group. Postoperative complications developed in 54% of the chemotherapy group and in 48% of the chemotherapy and bevacizumab group. Severe complications (grade III-V) occurred in only 13% and 12%, respectively (P = .822). Pathologic complete response (CR) was seen in 11/94 patients. Poor performance status (PS) before starting chemotherapy was associated with higher rates of complications (P = .002), and severe complications led to prolonged hospital admission (P = .001). Patients with pathologic CR had longer OS (P = .0275), but there was no difference in OS between responders and nonresponders (P = .778).ConclusionThe addition of bevacizumab to chemotherapy does not increase liver resection complication rates. Pathologic CR is associated with prolonged survival.     

鱼腥草总黄酮对人肿瘤细胞的抗肿瘤活性作用

目的探究鱼腥草黄酮类提取物对人子宫颈癌细胞株SiHa增殖和凋亡的影响。方法①采用20倍60%乙醇进行回流提取,大孔树脂分离提取纯化鱼腥草中黄酮类化合物;②应用四甲基偶氮唑蓝法检测黄酮类化合物对SiHa的细胞抑制率;③采用流式细胞术检测其对SiHa细胞凋亡的影响。结果①鱼腥草黄酮提取物有抑制SiHa细胞生长的作用,半数抑制浓度值为0.825 g/L;②鱼腥草黄酮提取物能以浓度依赖性诱导SiHa细胞的凋亡。结论鱼腥草黄酮提取物能抑制SiHa肿瘤细胞生长,诱导凋亡的作用,为鱼腥草的抗子宫颈癌的药效学效应提供了实验依据。