Function of HAb18G/CD147 in invasion of host cells by severe acute respiratory syndrome coronavirus

To identify the function of HAb18G/CD147 in invasion of host cells by severe acute respiratory syndrome (SARS) coronavirus (CoV), we analyzed the protein-protein interaction among HAb18G/CD147, cyclophilin A (CyPA), and SARS-CoV structural proteins by coimmunoprecipitation and surface plasmon resonance analysis. Although none of the SARS-CoV proteins was found to be directly bound to HAb18G/CD147, the nucleocapsid (N) protein of SARS-CoV was bound to CyPA, which interacted with HAb18G/CD147. Further research showed that HAb18G/CD147, a transmembrane molecule, was highly expressed on 293 cells and that CyPA was integrated with SARS-CoV. HAb18G/CD147-antagonistic peptide (AP)-9, an AP of HAb18G/CD147, had a high rate of binding to 293 cells and an inhibitory effect on SARS-CoV. These results show that HAb18G/CD147, mediated by CyPA bound to SARS-CoV N protein, plays a functional role in facilitating invasion of host cells by SARS-CoV. Our findings provide some evidence for the cytologic mechanism of invasion by SARS-CoV and provide a molecular basis for screening anti-SARS drugs.     

Mutation inε-Sarcoglycan Induces a Myoclonus-Dystonia Syndrome-Like Movement Disorder in Mice

Myoclonus dystonia syndrome(MDS)is an inherited movement disorder,and most MDS-related mutations have so far been found in theε-sarcoglycan(SGCE)coding gene.By generating SGCE-knockout(KO)and human 237 C>T mutation knock-in(KI)mice,we showed here that both KO and KI mice exerted typical movement defects similar to those of MDS patients.SGCE promoted filopodia development in vitro and inhibited excitatory synapse formation both in vivo and in vitro.Loss of function of SGCE leading to excessive excitatory synapses that may ultimately contribute to MDS pathology.Indeed,using a zebrafish MDS model,we found that among 1700 screened chemical compounds,Vigabatrin was the most potent in readily reversing MDS symptoms of mouse disease models.Our study strengthens the notion that mutations of SGCE lead to MDS and most likely,SGCE functions to brake synaptogenesis in the CNS.     

自体动静脉内瘘血栓危险因素的Meta分析

目的明确血液透析患者发生自体动静脉内瘘血栓(arteriovenous fistulas thrombus,AVFT)的危险因素,为预防血液透析患者AVFT的发生提供依据。方法计算机检索Cochrane Library、PubMed、Embase、Web Of Science、中国知网、万方数据库、维普数据库和中国生物医学文献数据库,搜集建库至2020年7月关于血液透析患者发生自体动静脉内瘘脉血栓危险因素的文献,利用RevMan 5.3软件进行Meta分析。结果共纳入20篇文献,包括49项相关危险因素。Meta分析结果,各危险因素的合并OR值(95%CI,P)分别为:C-反应蛋白1.16(1.08~1.26,P=0.001)、年龄1.02(1.01~1.03,P=0.001)、收缩压1.12(1.07~1.19,P<0.001)、糖尿病1.67(1.33~2.11,P<0.001)、女性2.50(1.83~3.42,P<0.001)、低血压5.57(2.88~10.75,P<0.001)。结论C-反应蛋白、高龄、收缩压、糖尿病、女性、低血压是血液透析自体动静脉内瘘血栓的危险因素,应针对血液透析人群中存在的AVFT的可控危险因素进行早期干预。     

糖尿病足的非增强MR成像血管灌注区域

摘要目的本研究的摘要目的是开发一种非对比MRI方法来评估以足部的血管灌注区域为基础的糖尿病足的骨骼肌肉灌注情况。方法对5例健康志愿者和5例无外周动脉疾     

Impaired fasting glucose and the prevalence and severity of angiographic coronary artery disease in high-risk Chinese patients

We assessed the relation between different fasting plasma glucose (FPG) levels of 5.6 to 6.9 mmol/L and the prevalence and severity of angiographic coronary artery disease (CAD) in high-risk Chinese patients. Among 512 subjects who were to undergo coronary angiography for the confirmation of suspected myocardial ischemia, 409 subjects were enrolled and categorized into 3 groups based on FPG levels: (1) 相似文献   

The Kv channel blocker 4-aminopyridine enhances Ag+ uptake: a scanning electrochemical microscopy study of single living cells

We report that silver ion (Ag⁺) uptake is enhanced by 4-aminopyridine (4-AP), a well known voltage-sensitive potassium ion channel (K_v) blocker. Both bacterial (Escherichia coli) and mammalian (3T3 fibroblast) cells were used as model systems. Ag⁺ uptake was monitored with a scanning electrochemical microscope with an amperometric Ag⁺ ion-selective electrode (Ag⁺-ISE) and the respiration rates of E. coli cells were measured by oxygen reduction at an ultramicroelectrode. The results showed that not only the amount but also the rate of silver uptake by the cells increased significantly when 4-AP was added to the solution. For fibroblasts, the Ag⁺ uptake rate was 4.8 × 10⁷ ions per cell per sec without 4-AP compared with 1.0 × 10⁸ ions per cell per sec with 0.2 mM 4-AP. For E. coli cells, the uptake rate was 1.5 × 10⁴ ions per cell per sec without 4-AP vs. 3.5 × 10⁴ ions per cell per sec with 0.5 mM 4-AP and 5.9 × 10⁴ ions per cell per sec with 1 mM 4-AP. Thus, 4-AP might be useful where silver is used as antimicrobial agent to speed its uptake.     

肌萎缩侧索硬化患者膈肌运动诱发电位

目的 初步探讨膈股运动诱发电位（DMEP）在肌萎缩侧索硬化（ALS）患者的应用及特点。方法 以表面电极在肋间隙处记录37例ALS患者及31例正常对照者经颅及经项磁刺激时产生的膈肌复合肌肉动作电位潜伏期和波幅,并计算中枢运动传导时间（CMCT）。22例ALS患者同时接受了用力肺活量百分比（％FVC）测定。结果 ALS患者较对照者颈及皮层潜伏期延长,颈及皮层波幅对数降低,CMCT延长,皮层潜伏期、皮层波幅对数、CMCT均与锥体束受累相关;皮层潜伏期和CMCT与临床呼吸困难相关,颈潜伏期与％FVC相关。结论 CMCT、颈及皮层潜伏期是DMEP参数中反映ALS患者呼吸功能障碍的敏感指标。CMCT反映ALS患者与呼吸功能相关的皮质脊髓束功能,CMCT与颈潜伏期结合有助于全面准确地揭示ALS患者呼吸受累的本质。     

Performance of a prehospital trauma diversion system in Hong Kong, China

Purpose: To evaluate the performance of a prehospital trauma diversion system in Hong Kong, China. Methods: A retrospective analysis of prospectively collected data in the trauma registry of Queen Mary Hospital, Hong Kong from 1 January 2009 to 31 December 2013 was done. All adult patients aged 18 years or above, either primarily or secondarily diverted to Queen Mary Hospital according to the trauma patient diversion protocol, were recruited. Need for trauma center level of care was based on a consensus-based criterion standard published in 2014. Performance of the protocol in terms of overdiversion and under-diversion was determined. Results: A total of 209 patients were included for analysis. About 30% of the patients required trauma center level of care. The most common reason was the need for vascular, neurologic, abdominal, thoracic, pelvic, spine or limb-conserving surgery within 24 h of presentation. The over-diversion rate and underdiversion rate were 69.6% and 19.7% respectively. Conclusion: The trauma patient diversion protocol currently in use in Hong Kong is not accurate enough. Further revision and refinement is needed.     

Helicobacter pylori specific immune response induced by conservative flagellin linear B-cell epitope

AIM:To testify the immunogenicity of a conservative B-cell linear epitope of Helicobacter pylori (H pylori) flagellin A. METHODS: Different programs were used to analyze the secondary structure, molecular hydropathy, and surface accessibility of H pylori flagellin A. Linear B-cell epitopes were estimated based on the structural and physiochemical information. Analysis of residue divergence was proposed to screen a conservative linear epitope. The 29-peptide (Pep29mer) synthesized by chemical method, including the predicted conservative B-cell epitope and a known K2d compatible T-cell epitope, was used to immunize mice, and then H pylori-specific antibodies were detected by ELISA. RESULTS: Based on the analyses of divergent amino acid residues, structural and physiochemical characteristics, it was strongly suggested that the short fragment NDSDGR was the core of a conservative linear epitope in flagellin A. Animals immunized by Pep29mer acquired efficient immune response. In detail, serum H pylori-specific IgA and IgGl increased significantly in immunized group, while IgG2a only had an insignificant change. H pylori-specific IgA in gastrointestinal flushing fluid also increased significantly. CONCLUSION: The conservative short fragment NDSDGR is the core of a linear B-cell epitope of flagellin A.