简介：AbstractBrucellosis is an important zoonotic infectious disease and is an important public health problem that causes serious economic consequences to the livestock industry. Brucella spp. comprise one of the most common pathogens causing laboratory-acquired infections (LAIs) and are becoming an increasingly important biosafety issue. To understand the significance of Brucella LAIs in China, related papers were search based on three Chinese databases (CNKI, Wanfang, and VIP), as well as PubMed. After assessment, 37 total cases were evaluated, including 27 students, seven laboratory technicians (one pregnant), two housekeeping staff, and one instructor. The age, sex, incubation period, pathogen detection results, and potential routes of infections were collected and analyzed. All LAIs occurred due to improper operations, inadequate biosafety training, and substandard laboratory safety conditions. Therefore, it is urgent to establish a comprehensive and systematic biosafety prevention/control system in laboratories to protect staff members from accidental exposures and LAIs; further, possible risks and control measures for the management of such infections were proposed.

简介：AbstractIn China, brucellosis has spread from the northern provinces to the southern coastal area, and Brucella melitensis has become the overwhelmingly dominant species nationwide. Although human Brucellosis cases have been reported in many parts of Hainan Province, investigations into the source of infection have been rare. In this case, we have used the techniques of bacteriology, genome sequencing, and WGS-SNP to investigate the source of infection on a patient with a traveling history between Hainan and Inner Mongolia autonomous regions. We collected a 5mL blood sample under sterile conditions from this suspected case of Brucellosis infection and incubated it in a culture bottle. A week later, Brucella colonies were purified and identified under the standard bacteriology procedures to show that the strain appeared as B. melitensis bv. 3. Subsequently, a draft genome sequencing of this strain was obtained. A WGS-SNP comparison analysis of Chinese B. melitensis selected (n = 36) from GenBank revealed that the strain in this study was more similar to the strains isolated from China's northern parts, especially those from the Inner Mongolia Autonomous Region. These data indicated that the source of infection of the patient was in the Inner Mongolia Autonomous Region, but the actual location where this patient became infected was unclear. We suggest that travelers from the southern part of China be cautious when visiting the traditional endemic areas of Brucellosis.

简介：AbstractBackground:The prevalence of human brucellosis in Qinghai Province of China has been increasing rapidly, with confirmed cases distributed across 31 counties. However, the epidemiology of brucellosis transmission has not been fully elucidated. To characterize the infecting strains isolated from humans, multiple-locus variable-number tandem repeats analysis (MLVA) and whole-genome single-nucleotide polymorphism (SNP)-based approaches were employed.Methods:Strains were isolated from two males blood cultures that were confirmed Brucella melitensis positive following biotyping and MLVA. Genomic DNA was extracted from these two strains, and whole-genome sequencing was performed. Next, SNP-based phylogenetic analysis was performed to compare the two strains to 94 B. melitensis strains (complete genome and draft genome) retrieved from online databases.Results:The two Brucella isolates were identified as B. melitensis biovar 3 (QH2019001 and QH2019005) following conventional biotyping and were found to have differences in their variable number tandem repeats (VNTRs) using MLVA-16. Phylogenetic examination assigned the 96 strains to five genotype groups, with QH2019001 and QH2019005 assigned to the same group, but different subgroups. Moreover, the QH2019005 strain was assigned to a new subgenotype, IIj, within genotype II. These findings were then combined to determine the geographic origin of the two Brucella strains.Conclusions:Utilizing a whole-genome SNP-based approach enabled differences between the two B. melitensis strains to be more clearly resolved, and facilitated the elucidation of their different evolutionary histories. This approach also revealed that QH2019005 is a member of a new subgenotype (IIj) with an ancient origin in the eastern Mediterranean Sea.

简介：Brucella流产胎是zoonotic在ruminants和人引起brucelosis的克否定的病原体。像使用费的受体(TLR)认出Brucella流产胎并且开始影响天生、适应的免疫的介绍抗原的房间活动。在这研究，我们集中了于recombinantBrucella房间表面蛋白质31(rBCSP31)在老鼠巨噬细胞上决定它的效果。我们表明的结果rBCSP31导致了TNF-α；，IL-6和IL-12p40生产，由刺激p38和JNK和抄写因素NF-κ的激活的快速的phosphorylation取决于激活mitogen的蛋白质kinases(MAPK)的激活，在巨噬细胞的B。另外，连续暴露(>；24h)RAW264.7，到rBCSP31的房间显著地提高了IFN-γ；MHC-II的导致的表示和介绍rBCSP31肽给CD4+T房间的能力。而且，我们发现rBCSP31能与TLR2和TLR4交往。由从TLR2−/−和TLR4−/−老鼠的巨噬细胞的导致rBCSP31的cytokine生产从NF-κ的C57BL/6巨噬细胞，和激活是比那低的；B和MAPK从TLR2−/−和TLR4−/−老鼠在巨噬细胞被稀释。另外，从与rBCSP31使免疫的C57BL/6老鼠的CD4+T房间生产了IFN-γ的高水平；并且IL-2与从TLR2−/−和TLR4−/−老鼠的CD4+T房间相比。从使免疫的C57BL/6老鼠的巨噬细胞从TLR2−/−和TLR4−/−老鼠比那些生产了IL-12p40的高水平。而且，有rBCSP31的免疫在B以后比在TLR2−/−和TLR4−/−老鼠在C57BL/6老鼠提供了更好的保护。流产胎2308挑战。这些结果显示rBCSP31是导致cytokine生产的TLR2和TLR4收缩筋，upregulates巨噬细胞功能并且导致Th1有免疫力的反应。