Genome-wide identification of antimicrobial peptides in the liver fluke,Clonorchis sinensis

The increase in prevalence of antimicrobial resistance makes the search for new antibiotic agents imperative. Antimicrobial peptides (AMPs) from natural resources have been recognized as suitable tools to combat antibiotic-resistant bacteria. The liver fluke Clonorchis sinensis living in germ-filled environments could be a good source of antimicrobials. Here, we report the use of a rational protocol that combines AMP predictions based on their physicochemical properties and their in vivo stability to discover AMP candidates from the entire genome of C. sinensis. To screen AMP candidates, in silico analyses based on the physicochemical properties of known AMPs, such as length, charge, isoelectric point, and in vitro and in vivo aggregation values were performed. To enhance their in vivo stability, proteins having proteolytic cleavage sites were excluded. As a consequence, four high-activity, highstability peptides were identified. These peptides could be potential starting materials for the development of new AMPs via structural modification and optimization. Thus, this study proposes a refined computational method to develop new AMPs and identifies four AMP candidates, which could serve as templates for further development of peptide antibiotics.     

阿奇霉素治疗小儿支原体肺炎的效果观察和安全性分析

目的观察大环内酯类抗生素阿奇霉素治疗小儿支原体肺炎的临床疗效,并对用药安全性进行评价。方法选择我院2012年6月至2014年10月呼吸科收治的96例小儿支原体肺炎患者,随机平均分为观察组和对照组。观察组给予阿奇霉素治疗,对照组给予红霉素治疗,观察两组的临床疗效和不良反应。结果观察组患者治愈37例,显效8例,无效3例,总有效率为93.75%;对照组治愈30例,显效9例,无效9例,总有效率为81.25%,治疗组疗效优于对照组,差异有统计学意义(P0.05)。治疗组患者平均退热、止咳、平喘、肺部啰音消失时间均短于对照组,平均住院时间和住院花费均少于对照组,差异有统计学意义(P0.05)。两组均偶见局部皮疹、注射部分疼痛等轻度不良反应,差异无统计学意义;观察组无胃肠道反应,对照组有4例胃肠道反应。结论阿奇霉素治疗小儿支原体肺炎能有效改善临床症状,较红霉素能提高治疗效果,缩短病程,且无严重不良反应,安全可靠,值得推广应用。     

Brucella suis vaccine strain S2-infected immortalized caprine endometrial epithelial cell lines induce non-apoptotic ER-stress

Brucella, which is regarded as an intracellular pathogen responsible for a zoonotic disease called brucellosis, survives and proliferates within several types of phagocytic and non-phagocytic cells. Brucella infects not only their preferred hosts but also other domestic and wild animal species, inducing abortion and infertility. Therefore, the interaction between uterine cells and Brucella is important for understanding the pathogenesis of this disease. In this study, we describe the Brucella suis vaccine strain S2 (B.suis.S2) infection and replication in the immortalized caprine endometrial epithelial cell line hTERT-EECs and the induced cellular and molecular response modulation in vitro. We found that B.suis S2 was able to infect and replicate to high titers and inhibit the proliferation of EECs and induce non-apoptotic pathways, as determined by B.suis.S2 detection using MTT and acridine orange/ethidium bromide (AO/EB) staining and flow cytometry. We explored the evidence of non-apoptotic pathways using real-time quantitative RT-PCR and by western blot analysis. Finally, we discovered the over-expression of GRP78, ATF4, ATF6, PERK, eIF2α, CHOP, and cytochrome c (Cyt-c) but not IRE1, xbp-1, and caspase-3 in B.suis.S2 (HK)-attacked and B.suis.S2-infected cells, suggesting that the molecular mechanism of ER stress sensor activation by B.suis.S2 is basically concomitant with that by B.suis.S2 (HK) and that ER stress, especially the PERK pathway, plays an important role in the process of B.suis.S2 infecting EEC, which may, in part, explain the role of the uterus in the pathogenesis of B.suis.S2.

Electronic supplementary material

The online version of this article (doi:10.1007/s12192-014-0564-x) contains supplementary material, which is available to authorized users.     

Development of a prototype wound dressing technology which can detect and report colonization by pathogenic bacteria

A new methodology for detecting the microbiological state of a wound dressing in terms of its colonization with pathogenic bacteria such as Staphylococcus aureus or Pseudomonas aeruginosa has been developed. Here we report how stabilized lipid vesicles containing self-quenched carboxyfluorescein dye are sensitive to lysis only by toxins/virulence factors from P. aeruginosa and S. aureus but not by a non-toxic Escherichia coli species. The development of the stabilized vesicles is discussed and their response to detergent (triton), bacterial toxin (α-hemolysin) and lipases (phospholipase A₂). Finally, fabrics with stabilized vesicles attached via plasma deposited maleic anhydride coupling are shown visibly responding to S. aureus (MSSA 476) and P. aeruginosa (PAO1) but not E. coli DH5α in a prototype dressing.     

肺炎支原体P1蛋白的研究进展

肺炎支原体(MP)是引起呼吸系统感染常见的病原微生物,P1蛋白是肺炎支原体上一种与黏附相关的跨膜蛋白,其黏附作用是引发炎症作用的重要原因.目前新发现的一种被称为孤立岛3的P1变异体引起了各学者的广泛关注.另外,还可以利用P1蛋白进行MP感染的实验室诊断.因此,探讨P1蛋白基因结构、致病机制和实验室诊断方法具有重要意义.     

肺炎支原体液体培养法检测的实验评价

目的比较液体培养法和固体培养法平行检测肺炎支原体结果的一致性;评价液体培养法检测肺炎支原体的可靠性。方法采用液体培养基和固体琼脂培养基平行检测1 648份临床标本的肺炎支原体,比较同一份标本在2种培养基上的检测结果。结果液体培养法阳性296例,阳性率为18%;固体培养法阳性244例,阳性率为14.8%;液体培养法阳性而固体培养法阴性57例;固体培养阳性而液体培养法为阴性5例。2种方法的阳性检出率比较差异有统计学意义(P<0.05)。结论肺炎支原体快速液体培养法与固体培养有较好的一致性,具有方便、简单、准确且可以用于早期检测等优点,适合临床大批量标本筛查。需结合患者临床症状等排除真菌和耐药菌造成的假阳性。