Statins and Voriconazole Induce Programmed Cell Death in Acanthamoeba castellanii

Members of the genus Acanthamoeba are facultative pathogens of humans, causing a sight-threatening keratitis and a life-threatening encephalitis. In order to treat those infections properly, it is necessary to target the treatment not only to the trophozoite but also to the cyst. Furthermore, it may be advantageous to avoid parasite killing by necrosis, which may induce local inflammation. We must also avoid toxicity of host tissue. Many drugs which target eukaryotes are known to induce programmed cell death (PCD), but this process is poorly characterized in Acanthamoeba. Here, we study the processes of programmed cell death in Acanthamoeba, induced by several drugs, such as statins and voriconazole. We tested atorvastatin, fluvastatin, simvastatin, and voriconazole at the 50% inhibitory concentrations (IC₅₀s) and IC₉₀s that we have previously established. In order to evaluate this phenomenon, we investigated the DNA fragmentation, one of the main characteristics of PCD, with quantitative and qualitative techniques. Also, the changes related to phosphatidylserine exposure on the external cell membrane and cell permeability were studied. Finally, because caspases are key to PCD pathways, caspase activity was evaluated in Acanthamoeba. All the drugs assayed in this study induced PCD in Acanthamoeba. To the best of our knowledge, this is the first study where PCD induced by drugs is described quantitatively and qualitatively in Acanthamoeba.     

临床护理路径对蝮蛇咬伤患者焦虑状态及满意度的影响

目的探讨临床护理路径对蝮蛇咬伤患者焦虑状态及住院满意度的影响。方法按随机数字表法将93例蝮蛇咬伤患者分为路径组46例和对照组47例。路径组应用临床护理路径,对照组采用常规护理。比较两组患者的焦虑状态及住院满意度。结果路径组焦虑得分低于对照组,住院满意度高于对照组,差异均有统计学意义(P<0.01)。结论应用临床护理路径促进了蝮蛇咬伤患者焦虑状态的缓解、提高了其住院满意度。     

改良Padua风险评估模型对评估内科住院患者静脉血栓栓塞症风险有效性研究

目的:回顾性验证改良Padua风险评估模型在内科住院患者中筛选静脉血栓栓塞症(VTE)的有效性。方法:采用回顾性病例对照研究设计,以2013年1月至2016年12月在广州医科大学附属第一医院内科住院患者中确诊为VTE的432例患者作为VTE组,以随机数字表法选取同时期同科室的出院诊断非VTE的864例内科住院患者为对照组,回顾性收集2组患者病史、实验室检查结果等临床资料,对所有患者进行Padua风险评估模型以及改良Padua风险评估模型评分,比较2种风险评估模型评分情况。结果:VTE组患者Padua风险评估模型评分高于对照组[(2.92±0.18)分比(1.25±0.10)分,t=16.241,P<0.05]。VTE组患者改良Padua风险评估模型评分高于对照组[(3.27±0.19)分比(1.64±0.11)分,t=14.245,P<0.05]。2组患者随着2种风险评估模型评分的升高,发生VTE的风险也相应增高,经Padua风险评估模型以及改良Padua风险评估模型判定为VTE高危患者(评分≥4分)发生VTE的风险分别是低危患者的12.72倍(95%CI:9.00~17.98,P<0.05)与8.17倍(95%CI:6.00~11.12,P<0.05)。VTE组患者经改良Padua风险评估模型判定为VTE高危患者占比高于Padua风险评估模型(48.61%比39.12%,P<0.05)。结论:改良Padua风险评估模型是基于个体危险因素对内科住院患者进行量化更加有效的VTE风险评估模型。     

Voriconazole as a first-line treatment against potentially pathogenic Acanthamoeba strains from Peru

Pathogenic strains of Acanthamoeba genus are the causative agents of fatal granulomatous amoebic encephalitis and a serious sight-threatening infection of the eye known as Acanthamoeba keratitis. In a previous study, Acanthamoeba strains were isolated from nasal swabs collected from healthy individuals in Peru. In the present study, the pathogenic potential of the isolated strains was established based on temperature and osmotolerance assays as well as the secretion rate of extracellular proteases. Based on these experiments, four strains that showed the highest pathogenic potential were selected for sensitivity assays against two molecules (voriconazole and chlorhexidine) which are currently used for the treatment of Acanthamoeba infections. After performing sensitivity and activity assays, it was found that both drugs were active against the tested strains. However, voriconazole showed higher activity against the studied strains compared to chlorhexidine. Therefore, voriconazole should be established as a first-line treatment against Acanthamoeba infections at least in the studied region of Peru.     

Could a patient with SMC1A duplication be classified as a human cohesinopathy?

The disorders caused by mutations in genes encoding subunits and accessory proteins of cohesin complex are collectively termed as cohesinopathies. The best known cohesinopathy is Cornelia de Lange Syndrome (CdLS), which is a multisystem developmental disorder characterized by facial dysmorphism, limb malformations, growth and cognitive impairment. Mutations in five genes, encoding subunits of the cohesin complex (SMC1A, SMC3, RAD21) and its regulators (NIPBL, HDAC8), are responsible for ～70% of CdLS cases. We describe a 16‐year‐old boy with facial dysmorphism, growth retardation, intellectual disability, hirsutism and small hands, who has a small Supernumerary Marker Chromosome (sSMC) present in mosaic form. sSMC is composed of two duplicated segments encompassing 17 genes including SMC1A gene, at the regions Xp11.22 and Xp11.21q11.1. Clinical comparison between our patient with a previously reported individual with a SMC1A duplication and four male carriers of similar sSMC reported in databases, suggest that they all share clinical features related to cohesinopathies. Although our patient does not have the classical CdLS craniofacial phenotype, he has pre and postnatal growth retardation, intellectual disability and mild musculoskeletal anomalies, features commonly seen in patients with cohesinopathies.     

LRP1-Dependent Endocytic Mechanism Governs the Signaling Output of the Bmp System in Endothelial Cells and in Angiogenesis

Rationale: Among the extracellular modulators of Bmp (bone morphogenetic protein) signaling, Bmper (Bmp endothelial cell precursor-derived regulator) both enhances and inhibits Bmp signaling. Recently we found that Bmper modulates Bmp4 activity via a concentration-dependent, endocytic trap-and-sink mechanism. Objective: To investigate the molecular mechanisms required for endocytosis of the Bmper/Bmp4 and signaling complex and determine the mechanism of Bmper's differential effects on Bmp4 signaling. Methods and Results: Using an array of biochemical and cell biology techniques, we report that LRP1 (LDL receptor-related protein 1), a member of the LDL receptor family, acts as an endocytic receptor for Bmper and a coreceptor of Bmp4 to mediate the endocytosis of the Bmper/Bmp4 signaling complex. Furthermore, we demonstrate that LRP1-dependent Bmper/Bmp4 endocytosis is essential for Bmp4 signaling, as evidenced by the phenotype of lrp1-deficient zebrafish, which have abnormal cardiovascular development and decreased Smad1/5/8 activity in key vasculogenic structures. Conclusions: Together, these data reveal a novel role for LRP1 in the regulation of Bmp4 signaling by regulating receptor complex endocytosis. In addition, these data introduce LRP1 as a critical regulator of vascular development. These observations demonstrate Bmper's ability to fine-tune Bmp4 signaling at the single-cell level, unlike the spatial regulatory mechanisms applied by other Bmp modulators.     

Heart failure in women

Heart failure (HF) has steadily increased in prevalence and affects both males and females equally. Despite this, there has been a significant underrepresentation of women in large scale HF trials. This disparity has lead to a deficit in understanding important gender-based differences in pathophysiology, diagnosis and treatment strategies. We review these gaps and explore a biological basis for varying outcomes. Endogenous estrogen plays an important role in epidemiology and outcome. The administration of exogenous estrogen has had varied success in treatment and is outlined extensively below. Additionally, we highlight unique HF syndromes through pregnancy and important sex-specific issues concerning transplant and mechanical circulatory support. A central theme remains: there is a clear need for increased female recruitment in clinical trials, and more studies exploring the role of gender-based biology in HF treatment.     

Infections with verotoxin-producing escherichia coli O157:H7 and other serotypes, including the outbreak strain O104:H4

Through the acquisition of mobile genetic elements, the normally harmless commensal Escherichia coli evolved into a highly adapted human pathogen. Pathogenic strains of E. coli are associated with urinary tract infections, sepsis/meningitis, and diarrhoea. At least six different diarrhoeagenic E. coli pathotypes have emerged during the past three decades as human pathogens of public health importance worldwide. In this review, we focus on the clinical features, pathogenic mechanisms, and diagnostic strategies of verotoxin-producing E. coli (VTEC) that are associated with sporadic cases and epidemics of gastrointestinal disease throughout the world. Recently, an E. coli strain of serotype O104:H4 combining verotoxin production with virulence factors of another pathotype, the enteroaggregative E. coli (EAEC), emerged as the cause of a severe outbreak in Europe.     

蛋白酶激活受体-2在急性坏死性胰腺炎大鼠肠黏膜组织中的表达

目的 探讨蛋白酶激活受体-2(PAR-2)的表达与急性坏死性胰腺炎(ANP)大鼠肠黏膜屏障损伤的相关性.方法 制备ANP大鼠模型,采用免疫组织化学法、Western印迹法及RT-PCR方法检测假手术对照组和造模后6、12、24 h大鼠肠黏膜组织中PAR-2的表达.组间数据比较采用单因素方差分析.结果 免疫组织化学法显示,假手术对照组大鼠小肠黏膜组织中PAR-2的表达较微弱.ANP造模后,PAR-2阳性细胞表达数量明显增加,染色强度明显增强.造模后6、12、24 h的免疫组织化学评分分别为4.88±0.33、5.87±0.32、11.17±0.27,与假手术对照组(2.86±0.31)相比,差异有统计学意义(F=747.08,P＜0.01).假手术对照组大鼠小肠黏膜中PAR-2的mRNA和蛋白表达量均较少,随着ANP造模时间的延长,两者的表达水平均逐渐升高,造模后6、12、24 h,mRNA分别为0.56±0.03、0.69±0.03、1.05±0.05,蛋白分别为0.28±0.02、0.35±0.03、0.69土0.04;各时间点与假手术对照组相比,差异均有统计学意义(F=785.69、1177.82,P值均＜0.01).结论 PAR-2在ANP炎性反应中被激活,在肠黏膜屏障损伤的发生发展过程中发挥重要作用.