简介：AbstractThe low success rates in the treatment of multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant TB (XDR-TB), which account for 55% and 34% respectively, led the WHO to conclude that MDR/XDR-TB is a serious public health crisis. However, the virulence of MDR/XDR-Mycobacterium Tuberculosis(Mtb) has not been analyzed in details, which could provide a specific guidance for the control and prevention. In this review, we discuss different aspects of MDR/XDR-Mtb virulence and its relationship to fitness cost by probing the following questions: (1) what mediates the virulence of MDR/XDR-Mtb? (What is the relationship between fitness and virulence of Mtb? (2) Is it possible that drug-resistant Mtb(DR Mtb) can show higher fitness? (3) What is the definite effect on fitness of each drug-resistant mutant? (4) What other important factors affecting fitness in the mutant strain? (5) How to study the virulence of a large number of DR Mtb?And what prevention and control measures will be taken in the future, especially for the high virulent DR Mtb? We therefore summarized the congruent relationship between drug resistance and fitness from the global response-related genes to antibiotic resistance-contributing mutation, provided methods to explore the virulence of DR Mtb. This review may offer some critical information and concise guide to creating strategies for the prevention and control of drug-resistant Mtb.

简介：为了成功地感染，招待房间并且躲避主机免疫者反应，一个类型III分泌物系统(T3SS)被伤寒通常使用细菌的病原体象enteropathogenicEscherichiacoli(EPEC)那样。最近的调查结果表明了各种各样的受动器通过T3SS被注入主人房间并且在煽动性的发信号的小径上施加禁止的效果，破坏对这些病原体的有免疫力的回答。这里，我们考察针对探讨EPEC受动器蛋白质调制的几条重要煽动性的发信号小径的调整的最近的研究，例如原子factor-B(NF-B)和激活mitogen的蛋白质kinase(MAPK)小径，它在这块未经勘探的地和帮助里提供卓见进未完成的工作为EPEC受动器在煽动性的发信号的网络识别新奇位置。

简介：ARCandNDcolonywereobtainedbyrearingthewhitebackedplanthopper(WBPH),Sogatellafurcifera(Horvath),exclusivelyonARC10239(ARC,carryingresistancegeneWbph2)andN'DiangMarie(ND,carryingresistancegeneWbphS)till15generations.TaichungNative1(TN1)andRathuHeenati(RHT)servedassusceptibleandresistantcheck,respectively.TheresultsofelectronicrecordingrevealedthatdurationofsalivationandX-waveformofthetwocoloniesontheircorrespondinghostswasshortwhilethedurationofphloemingestionwaslong.TheamountofhoneydewexcretedbyARCandNDcolonydidnotdifferontheircorrespondinghostvarietiesfromTN1andwasmuchhigherthanthatofRHT.ThenumberofeggslaidontheirhostvarietiesandTN1weresignificantlyhigherthanthatonRHT.Nodistinctchangewasobservedforthesetwocoloniesintermofpercentageofdevelopedeggs.ThenymphsurvivalrateofNDcolonyonitsselectionhostwas45.0%,significantlydifferentfromthatonTN1(71.4%0)andRHT(21.0%),whilethatofARCcolonywas68.3%,notsignificantlydifferentfromthatonTN1(77.5%),butmuchhigherthanthatonRHT(22.6%).ThenymphaldevelopmentdurationofthesetwocoloniesonthecorrespondinghostswasnotdifferentfromthatonTN1,butsignificantlyshorterthanthatonRHT.Inbrief,thesetwocolonieshadalmostadaptedtotheircorrespondinghostvarietiesbasedonfeedingandoviposition,butthenymphalsurvivalrateofNDcolonywasstilllow.

简介：AbstractObjective:Pseudomonas aeruginosa (P. aeruginosa) contains a hierarchy of quorum sensing (QS) network, consisting of the las, rhl and pqs systems, which play a key role in coordinating the expression of virulence factors. PA2146 was found to be associated with P. aeruginosa pathogenicity in macrophage and host Immune response. The aim of this study was to investigate the effects of PA2146 on the virulence of P. aeruginosa and explore its mechanism.Methods:PA2146 gene knockout strain and complement strain of P. aeruginosa PAO1 were constructed. The biomass of biofilm was detected by crystal violet staining; the virulence factors were measured, including pyocyanin, rhamnolipid, LasA elastase, LasB elastase and hemolytic activity; RNA-seq and label-free relative quantitative proteomics analyses were carried out to test the influence of PA2146 on transcriptomics and proteomics. This study was approved by the Institutional Review Board of the Third Xiangya Hospital, Central South University, China (approval No. 2019-S021).Results:PA2146-deficient strains showed reduced biofilm formation and increased pyocyanin, rhamnolipid, LasA elastase, LasB elastase, and hemolytic activity, as well as increased motility, compared with the wild-type strain. RNA-seq and label-free relative quantitative proteomics analyses revealed that PA2146 repressed the transcription of several genes that are integral to the pqs system and to pyocyanin biosynthesis, and increased the expression of MexEF-OprN efflux pump components at the gene and protein level.Conclusion:PA2146 gene was found to inhibit the pqs system. PA2146 may affect quorum sensing by directly inhibiting the pqs system or by enhancing the expression of MexEF-OprN efflux pump components, thereby promoting efflux of 2-heptyl-4(1H)-quinolone, a Pseudomonas quinolone signal precursor, and thus affecting P. aeruginosa virulence.

简介：AbstractThe virulence of influenza viruses is a complex multigenic trait. Previous studies about the virulence determinants of influenza viruses mainly focused on amino acid sites, ignoring the influence of nucleotide mutations. In this study, we collected >200 viral strains from 21 subtypes of influenza A viruses with virulence in mammals and obtained over 100 mammalian virulence-related nucleotide sites across the genome by computational analysis. Fifty of these nucleotide sites only experienced synonymous mutations. Experiments showed that synonymous mutations in three high-scoring nucleotide sites, i.e., PB1–2031, PB1–633, and PB1–720, enhanced the pathogenicity of the influenza A(H1N1) viruses in mice. Besides, machine-learning models with accepted accuracy for predicting mammalian virulence of influenza A viruses were built. Overall, this study highlighted the importance of nucleotide mutations, especially synonymous mutations in viral virulence, and provided rapid methods for evaluating the virulence of influenza A viruses. It could be helpful for early warning of newly emerging influenza A viruses.

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简介：AbstractSince severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first identified during late 2019, the sustained spread of this pathogen within the human population has caused worldwide disruption with staggering infection rates and death tolls. Due to the accumulation of mutations in SARS-CoV-2, the virus has evolved into many variants, five of which have been listed as variants of concern VOCs by the World Health Organization (WHO). Multiple animal models of SARS-CoV-2 have been developed to evaluate vaccines and drugs and to assess the pathogenicity, transmissibility and antiviral measures of these VOCs. Here, we review the cutting-edge research based on mouse, hamster, ferret and non-human primate models for evaluating SARS-CoV-2 with a focus on the Omicron variant, and highlight the importance of updating vaccines in a timely manner in order to mitigate the negative effects of SARS-CoV-2 infections in the human population.

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简介：棕色的planthopperNilaparvatalugensStål(Homoptera：Delphacidae)由在米饭上并且也喂的罐头原因hopperburn能播送草多的绝技疾病。抵抗米饭变化被开发了，但是几N。lugens紧张能恢复他们的毒力到这些抵抗米饭变化。在现在的学习，在N与稳定的表达式层次引用基因。lugens人口显示出毒力的不同层次到易受影响、抵抗的米饭变化。在N的六候选人参考基因的表示。在易受影响、抵抗的米饭变化上喂的lugens被分析。这些基因在微分基因表示的分析为他们的潜在的使用被评估。聚合酶链反应数据从N被产生。lugens，包括二个不同处理(抵抗或易受影响的米饭)和三剧毒的N。lugens人口。三个软件程序(BestKeeper，Normfinder和geNorm)被用来估计候选人引用基因。geNorm和Normfinder作为最稳定的参考基因识别了基因18S，-ACT,澡盆和澡盆。而18S和澡盆分别地是第二和第三最稳定地表示的基因，BestKeeper与最少的全面变化作为最佳的参考基因识别了ETIF1。因此，我们断定基因18S和澡盆是在N的最合适的参考基因。lugens。这些结果将便于在N上介绍研究的未来抄本。在不同米饭变化上在毒力层次显示出变化的lugens人口。

简介：从古巴的蝎子Rhopalurusjunceus表示昆虫选择的神经毒素(RjAa17f)的recombinantHelicoverpaarmigeranucleopolyhedrovirus(HearNPV)被用红相应再结合系统代替UDP-glucosyltransferase基因(egt)构造。另一egt删除了控制HearNPV被把egfp基因插入到egt地点以一个类似的方法构造。一步舞病毒的生长曲线和病毒的DNA复制曲线分析证实再结合没在宿主细胞影响病毒的生长和DNA复制。在在RjAa17f-HearNPV，Egfp-HearNPV和HZ8-HearNPV之间的吸藏身体形态发生没有可辨别的差别，它被传播电子显微镜学分析证实。然而，RjAa17f-HearNPV的杀虫的活动对第三中间形态H被提高。armigera幼虫根据毒力比较上的生物鉴定。在中部的致命的剂量有戏剧的减小(56.9%)(LD50)并且另外在中部的幸存时间的减小(13.4%)(为与HZ8-HearNPV相比的recombinantRjAa17f-HearNPV的圣50)，但是当Egfp-HearNPV与HZ8-HearNPV相比时，仅仅在LD50的27.5%减小和在圣50的10.1%减小珍视。每日的食谱消费分析证明RjAa17f-HearNPV能禁止减HearNPV与egt相比喂的感染的幼虫。这些结果证明这新奇recombinantRjAa17f-HearNPV能对它的主人昆虫改进杀虫的效果，RjAa17f能是另外的recombinantbaculovirus构造的一个可观的候选人。