A novel human enterovirus recombinant from a child with diarrhea

Recombination is a well-known phenomenon for enteroviruses. In the present study, a novel recombinant HEV-B strain (ChZJ-1) was found in a 2-year-old child with diarrhea in Zhenjiang, China. The whole genome of ChZJ-1 was determined. Recombination and phylogenetic analysis revealed that ChZJ-1 might have been produced by recombination between coxsackievirus B5 and echovirus 18.     

Unraveling the mechanism of CO2 capture and separation by porous liquids

Carbon dioxide (CO₂) emissions intensify the greenhouse effect so much that its capture and separation are needed. Porous liquids, possessing both the porous properties of solids and the fluidity of liquids, exhibit a wide range of applications in absorbing CO₂, but the mechanism of gas capture and separation demands in-depth understanding. To this end, we provide a molecular perspective of gas absorption in a porous liquid composed of porous organic cages dissolved in a size-excluded solvent, hexachloropropene, by density functional theory for the first time. In this work, different conformations were considered comprehensively for three representative porous organic cages and molecules. Results show that chloroform, compared to CO₂, tends to enter the cage due to stronger C–H⋯π interaction and the optimal capacity of each cage to absorb CO₂ through hydrogen bonding and π–π interaction is 4, 2 and 4 equivalents, respectively. We hope that these discoveries will promote the synthesis of similar porous liquids that are used to capture and separate gases.

A POC-type porous liquid has the ability to absorb CO₂ and the cage provides a cavity for absorption. The dominant interaction between CO₂ and the cage is π–π interaction. The optimal capacities of the three porous organic cages are 4, 2 and 4 eq.     

N6-methyladenine and epigenetic immunity of Deinococcus radiodurans

DNA methylation is ubiquitously found in all three domains of life. This epigenetic modification on adenine or cytosine residues serves to regulate gene expression or to defend against invading DNA in bacteria. Here, we report the significance of N6-methyladenine (6mA) to epigenetic immunity in Deinococcus radiodurans. Putative protein encoded by DR_2267 ORF (Dam2_DR) contributed 35% of genomic 6mA in D. radiodurans but did not influence gene expression or radiation resistance. Dam2_DR was characterized to be a functional S-adenosyl methionine (SAM)-dependent N6-adenine DNA methyltransferase (MTase) but with no endonuclease activity. Adenine methylation from Dam2_DR or Dam1_DR (N6-adenine MTase encoded by DR_0643) improved DNA uptake during natural transformation. To the contrary, methylation from Escherichia coli N6-adenine MTase (Dam_EC that methylates adenine in GATC sequence) on donor plasmid drastically reduced DNA uptake in D. radiodurans, even in presence of Dam2_DR or Dam1_DR methylated adenines. With these results, we conclude that self-type N6-adenine methylation on donor DNA had a protective effect in absence of additional foreign methylation, a separate methylation-dependent Restriction Modification (R-M) system effectively identifies and limits uptake of G6mATC sequence containing donor DNA. This is the first report demonstrating presence of epigenetic immunity in D. radiodurans.     

Klebsiella MALDI TypeR: a web-based tool for Klebsiella identification based on MALDI-TOF mass spectrometry

Klebsiella pathogens affect human and animal health and are widely distributed in the environment. Among these, the Klebsiella pneumoniae species complex, which includes seven phylogroups, is an important cause of community and hospital infections. The Klebsiella oxytoca species complex also causes hospital infections and antibiotic-associated haemorrhagic colitis. The unsuitability of currently used clinical microbiology methods to distinguish species within each of these species complexes leads to high rates of misidentifications that are masking the true clinical significance and potential epidemiological specificities of individual species.We developed a web-based tool, Klebsiella MALDI TypeR, a platform-independent and user-friendly application that enables uploading MALDI-TOF mass spectrometry data in order to identify Klebsiella isolates at the species complex and phylogroup levels. The tool, available at https://maldityper.pasteur.fr/, leverages a database of previously identified biomarkers that are specific for species complexes, individual phylogroups, or related phylogroups. We obtained 84%–100% identification accuracy depending on phylogroup. Identification results are obtained in a few seconds from batches of uploaded spectral data.Klebsiella MALDI TypeR enables fast and reliable identification of Klebsiella strains that are often misidentified with standard microbiological methods. This web-based identification tool may be extended in the future to other human bacterial pathogens.     

An improved design of axially driven permanent maglev centrifugal pump with streamlined impeller

Background: In 1839, Earnshaw proved theoretically that it is impossible to achieve a stable equilibrium with a pure permanent maglev. Furthermore, in 1939, Braunbeck deduced that it is only possible to stabilize a super conductive or an electric maglev. In 2000, however, the present authors discovered that stable levitation is achievable by a combination of permanent magnetic and nonmagnetic forces, and its stability can be maintained even with mere passive magnetic forces by use of the gyro-effect.

Design concepts: An improved design of permanent maglev impeller pump has been developed. Passive magnetic (PM) bearings support the rotor radially; on its right side, an impeller is fixed and on its left side a motor magnets-assemble is mounted. Unlike a previous prototype design, in which the rotor magnets were driven by a motor via magnetic coupling, a motor coil is installed opposite to the motor magnets disc, producing a rotating magnetic field. At standstill or if the rotating speed is lower than 4000 rpm, the rotor has one axial point contact with the motor coil. The contact point is located at the centre of the rotor. As the rotating speed increases gradually to higher than 4000 rpm, the rotor will be drawn off from the contact point by the hydrodynamic force of the fluid. Then the rotor becomes fully suspended.

Key points of stabilization: For radial and peripheral stabilization, a gyro-effect is important, which is realized by designing the motor magnets disc to have large diameter, short length and high rotating speed; for axial stability, an axial rehabilitating force is necessary, which is produced by PM bearings.

Results: The rotor demonstrated a full levitation by rotation over 4000 rpm. As a left ventricular assist device, the rotation of the pump has a speed range from 5000 to 8000 rpm. The relation between pressure head and flow rate indicates that there is neither mechanical friction nor hydrodynamic turbulence inside the pump; the former is due to the frictionless maglev and the latter is a result of the streamlined design of the impeller.     

髋关节置换手术定制型髓腔锉的设计与加工

目的 介绍定制型髓腔锉的设计与加工方法。方法 根据相应的定制型股骨柄假体的三维模型设计髓腔锉,在计算机辅助设计（CAD）软件中,通过截除、拉伸及偏移面等操作构建出髓腔锉三维模型。采用计算机辅助制造（CAM）技术加工出定制型髓腔锉。采用本研究的CAD及CAM方法,分别为实验及临床试用设计加工了定制型髓腔锉。结果 实验及临床试用的定制型髓腔锉被用于切削相应的尸体股骨腔及患者股骨腔,植入定制型假体以后,通过分析发现假体与股骨腔匹配较好。结论 采用该研究方法设计加工定制型髓腔锉,将能够提高植入定制型股骨柄假体的成功率,将减少定制型股骨柄假体在患者股骨腔中松动的风险,能够促进股骨松质骨长入假体表面来固定假体。     

Marginalized evidence: Effective knowledge translation strategies for low awareness issues

There are particular knowledge translation (KT) challenges in communicating evidence on low awareness topics. Often considered peripheral to the main focus of health care provision, these issues may fail to “get on the agenda” of decision-makers, even when supported by strong evidence. This article describes the successful application of KT strategies to a specific low awareness issue (the importance of using trained health interpreters) within a large Canadian Regional Health Authority.