Advances in multiplex nucleic acid diagnostics for blood-borne pathogens: promises and pitfalls - an update

Introduction: Multiplex nucleic acid diagnostics for blood-borne pathogens have moved closer to clinical application in the two years since we first reviewed this topic.

Areas covered: A new emphasis on detecting pathogens directly in a blood sample without culture, coupling PCR amplification to microfluidic devices and higher multiplexing in isothermal amplification are some of the advances. A wholly new approach of correlating host gene expression response with specific infectious agents opens another opportunity for multiplex detection. Established microarrays, which had been the highest multiplicity platform, are being displaced by Next Generation Sequencing (NGS) having potentially no limit to the number of pathogens that it can identify. Greater accessibility of sequencing devices, standardization of bioinformatic analysis pathways and increased acceptance from regulatory authorities are driving this technology.

Expert commentary: The landscape of traditional diagnostics for detection of blood-borne pathogens has changed in the last 5 years. There is no doubt that NSG is recognized as a disruptive technology with a growing repertoire of tools, such as subtyping, resistome analysis, etc., available for clinical microbiology. Increasing acceptance indicates the dominating position of NGS as the future of multiplex molecular diagnostics for blood-borne pathogens.     

良附丸对寒邪客胃证大鼠胃排空及小肠推进度的影响

目的研究良附丸对寒邪客胃证大鼠胃排空和小肠推进度的影响。方法采用冰水灌胃(内寒)、冰敷胃部(外寒)复制寒邪客胃证大鼠动物模型,边给药边造模,实验7 d后,大鼠予以半固体糊灌胃,30 min后水合氯醛麻醉,解剖检测指标。结果良附丸对治内大鼠饮食、体质量的改善无显著作用(P> 0.05),但能增加饮水量(P <0.01),对治外和治混大鼠的饮食、饮水、体质量均有明显的改善作用(P <0.05);治疗组胃残留率和排空率虽有改善趋势,但无统计学差异(P> 0.05);治疗组小肠推进率显著增加(P <0.05),差异具有统计学意义。结论内寒对大鼠饮食、体质量,外寒对大鼠小肠推进度影响均不大。良附丸不能显著改善胃实寒大鼠胃排空状态,但有改善的趋势;良附丸能显著改善寒邪客胃证(内、混)大鼠小肠推进率,促进胃肠蠕动。     

The healthy workplace project: Reduced viral exposure in an office setting

Viral illnesses such as gastroenteritis and the common cold create a substantial burden in the workplace due to reduced productivity, increased absenteeism, and increased health care costs. Behaviors in the workplace contribute to the spread of human viruses via direct contact between hands, contaminated surfaces, and the mouth, eyes, and/or nose. This study assessed whether implementation of the Healthy Workplace Project (HWP) (providing hand sanitizers, disinfecting wipes, facial tissues, and use instructions) would reduce viral loads in an office setting of approximately 80 employees after seeding fomites and the hands of volunteer participants with an MS-2 phage tracer. The HWP significantly reduced viable phage detected on participants’ hands, communal fomites, and personal fomites (p ≤ .010) in office environments and presents a cost-effective method for reducing the health and economic burden associated with viral illnesses in the workplace.     

Diverse immune functions of hemocyanins

Substantial evidence gathered recently has revealed the multiple functionalities of hemocyanin. Contrary to previous claims that this ancient protein is involved solely in oxygen transport within the hemolymph of invertebrates, hemocyanin and hemocyanin-derived peptides have been linked to key aspects of innate immunity, in particular, antiviral and phenoloxidase-like activities. Both phenoloxidase and hemocyanin belong to the family of type-3 copper proteins and share a high degree of sequence homology. While the importance of phenoloxidase in immunity and development is well characterised, the contribution of hemocyanin to biological defence systems within invertebrates is not recognised widely.     

Virulence factors impair epithelial junctions during bacterial infection

Epithelial cells are typically connected through different types of cell junctions that are localized from the apical membrane to the basal surface. In this way, epithelium cells form the first barrier against pathogenic microorganisms and prevent their entry into internal organs and the circulatory system. Recent studies demonstrate that bacterial pathogens disrupt epithelial cell junctions through targeting junctional proteins by secreted virulence factors. In this review, we discuss the diverse strategies used by common bacterial pathogens, including Pseudomonas aeruginosa, Helicobacter pylori, and enteropathogenic Escherichia coli, to disrupt epithelial cell junctions during infection. We also discuss the potential of targeting the pathogenic mechanisms in the treatment of pathogen‐associated diseases.     

The role of trehalose in the global spread of epidemic Clostridium difficile

In a recent study, we reported on two distantly related, epidemic lineages of Clostridium difficile that have acquired independent mechanisms to metabolize low concentrations of trehalose. Here we provide further comment and evidence that a third epidemic lineage common in Asia and Europe, ribotype 017, has evolved this ability.     

牙周炎与癌症相关性研究进展

牙周炎与全身健康和系统性疾病密切相关。近年来，多项研究发现牙周炎与癌症之间存在着相关性，牙周炎对癌症的发生和发展具有促进作用，牙周炎患者患癌风险增加，但其具体机制尚未明确。本文就牙周炎与头颈癌、消化道癌、肺癌、肝癌、乳腺癌等癌症的相关性及相关机制作一综述。     

Role of viral RNA and lipid in the adverse events associated with the 2010 Southern Hemisphere trivalent influenza vaccine

In Australia, during the 2010 Southern Hemisphere (SH) influenza season, there was an unexpected increase in post-marketing adverse event reports of febrile seizures (FS) in children under 5 years of age shortly after vaccination with the CSL 2010 SH trivalent influenza vaccine (CSL 2010 SH TIV) compared to previous CSL TIVs and other licensed 2010 SH TIVs. In an accompanying study, we described the contribution to these adverse events of the 2010 SH influenza strains as expressed in the CSL 2010 SH TIV using in vitro cytokine/chemokine secretion from whole blood cells and induction of NF-κB activation in HEK293 reporter cells. The aim of the present study was to identify the root cause components that elicited the elevated cytokine/chemokine and NF-κB signature. Our studies demonstrated that the pyrogenic signal was associated with a heat-labile, viral-derived component(s) in the CSL 2010 SH TIV. Further, it was found that viral lipid-mediated delivery of short, fragmented viral RNA was the key trigger for the increased cytokine/chemokine secretion and NF-κB activation. It is likely that the FS reported in children <5 years were due to a combination of the new influenza strains included in the 2010 SH TIV and the CSL standard method of manufacture preserving strain-specific viral components of the new influenza strains (particularly B/Brisbane/60/2008 and to a lesser extent H1N1 A/California/07/2009). These combined to heighten immune activation of innate immune cells, which in a small proportion of children <5 years of age is associated with the occurrence of FS. The data also demonstrates that CSL TIVs formulated with increased levels of splitting agent (TDOC) for the B/Brisbane/60/2008 strain can attenuate the pro-inflammatory signals in vitro, identifying a potential path forward for generating a CSL TIV indicated for use in children <5 years.