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1.
《Vaccine》2019,37(43):6255-6261
Health workers represent an important target group for seasonal influenza vaccination because of their increased risk of infection as well as the risk of transmitting infection to vulnerable patients in the health care setting. Moreover, seasonal vaccination of health workers contributes to pandemic preparedness. However, many countries, especially in Africa and Asia, do not have policies for health worker influenza vaccination. In countries where such policies exist, vaccination coverage is often low. The World Health Organization (WHO) is developing a manual to guide the introduction of seasonal influenza vaccination of health workers. An Independent External Advisory Group (IEAG) that is advising WHO on the content of the manual met to discuss issues that are relevant and often unique to health worker vaccination. This meeting report summarizes the main issues that were discussed and the outcomes of the discussion. The issues include policy considerations, including the evidence in support of health worker vaccination; categorization and prioritization of health workers; the choice of vaccination strategy; its integration into broader health worker vaccination and occupational health policies; planning and management of vaccination, particularly the approaches for communication and demand generation; and the challenges with monitoring and evaluation of health worker vaccination, especially in low and middle-income countries. 相似文献
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BackgroundTuberculosis meningitis (TBM) is the most severe form of tuberculosis, and currently lacks efficient diagnostic approaches. Metabolomics has the potential to differentiate patients with TBM from those with other forms of meningitis and meningitis-negative individuals. However, no systemic metabolomics research has compared the cerebrospinal fluid (CSF) of these patients.Methods1H nuclear magnetic resonance (NMR) was used for CSF metabolic profiling. Principal component analysis and orthogonal signal correction-partial least squares-discriminant analysis (OPLS-DA) were used to screen for important variables. The Human Metabolome Database was used to identify metabolites, and MetaboAnalyst 4.0 was used for pathway analysis and over-representation analysis.ResultsOPLS-DA modeling could distinguish TBM from other forms of meningitis, and several significantly changed metabolites were identified. Additionally, 23, 6, and 21 metabolites were able to differentiate TBM from viral meningitis, bacterial meningitis, and meningitis-negative groups, respectively. Pathway analysis indicated that these metabolites were mainly involved in carbohydrate and amino acid metabolism, and over-representation analysis indicated that some of these pathways were over-represented.ConclusionsThe metabolites identified have the potential to serve as biomarkers for TBM diagnosis, and carbohydrate and amino acid metabolism are perturbed in the CSF of patents with TBM. Metabolomics is a valuable approach for screening TBM biomarkers. With further investigation, the metabolites identified in this study could aid in TBM diagnosis. 相似文献
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霍乱弧菌溶原性噬菌体CTXΦ的氯霉素抗性基因标记及诱导 总被引:9,自引:0,他引:9
目的 对携带霍乱毒素基因的溶原性噬菌体CTXΦ进行遗传标记 ,以深入研究CTXΦ对霍乱弧菌的转染机制。方法 将CTXΦ基因组中ctxAB的上下游同源序列连接到cat基因的两侧 ,然后通过自杀质粒介导的DNA同源重组技术将霍乱菌株N16 96 1染色体上CTXΦ基因组中的ctxAB基因缺失掉 ,替换以氯霉素抗性基因 ,对CTXΦ基因组进行遗传标记 ,然后用丝裂霉素C诱导这种经抗性基因标记的噬菌体 ,再利用它对古典型霍乱弧菌的转染检测活性。结果 获得了ctxAB缺失、带有cat遗传标记的重组菌株N Φc;诱导出的CTXΦc噬菌体颗粒成功感染了霍乱菌株 1119。结论 N Φc中的CTXΦ带有了氯霉素抗性标记 ,诱导出具有感染活性的CTXΦc可用于研究毒力基因的水平转移 相似文献
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《Ticks and Tick》2022,13(1):101861
Anaplasmosis is a rickettsial infection with significant effects on human and animal health, and the discovery of new species or genotypes with zoonotic potential in recent years has increased this importance. The aim of this study was to provide the first assessment of the molecular etiology and prevalence of bovine anaplasmosis in Kyrgyzstan (specifically in the Chuy, Talas, Djalal-Abad, Naryn, and Issyk-Kul regions). The prevalence of bovine anaplasmosis was determined as 1.7% (6/358). PCR and partial DNA sequencing results of the 16S ribosomal RNA (rRNA) gene revealed that Anaplasma centrale, A. phagocytophilum like-1, and the human pathogenic novel genotype A. capra are circulating in cattle herds in Kyrgyzstan. Six DNA nucleotide sequences obtained in this study were deposited in GenBank under the following accession numbers: A. centrale (MW672117, MW672118, MW672119, MW672120), A. phagocytophilum (MW672121), and A. capra (MW672115). 相似文献
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《Ticks and Tick》2022,13(5):101974
Rodents are generally recognized to be the reservoir hosts of a great many zoonotic pathogens. In some areas of China, rodent-borne pathogens, as well as the role of rodents in the natural cycle of these pathogens, are still poorly investigated. To increase our knowledge on the distribution and epidemiology of rodent-borne bacterial pathogens, 81 rodent liver samples were collected in three locations of Guizhou province located in Southwest China, and screened for the presence of Ehrlichia, Coxiella, and Bartonella in them. A putative novel Ehrlichia species was identified in 5 Berylmys bowersi samples (100%, 5/5). Its 16S rRNA, gltA, and groEL genes have highest 99.84%, 89.11%, and 98.02% identities to those from known Ehrlichia species, and form distinct clades in the phylogenetic trees. Herein we name it “Candidatus Ehrlichia zunyiensis”. Bartonella was tested positive in 8 A. agrarius (striped field mouse), 2 A. chevrieri (Chevrier's field mouse), 1 R. norvegicus (Norway rat), 1 N. confucianus, and 1 N. lotipes, with a total positive rate of 16.05% (13/81). Sequence analysis indicated high genetic diversity in these Bartonella strains. Unexpectedly, two Coxiella strains were identified from the rodents (1 Niviventer confucianus and 1 Mus pahari). Genetic and phylogenetic analysis indicated that both of them are closely related to the Coxiella endosymbiont of ticks. This result supported previous conjectures that vertebrate hosts such as rodents may play a role in the preservation and transmission of Coxiella endosymbiont of ticks. 相似文献
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《Ticks and Tick》2022,13(5):101985
Rickettsial diseases are recognized as one of the most important vector-borne infectious diseases for humans all over the world. Dogs and their ticks are considered the most important reservoirs for Rickettsia spp., especially in spotted fever group rickettsioses. The aim of the study was to investigate Rickettsia infections in ticks collected from stray dogs in southeastern Iran. In this study, 50 stray dogs in Kerman city were randomly selected, of 68% and 52% of which were above 8 months age and male, respectively. Ticks were collected from the dog skins. After identification of collected ticks, genomic DNA of all ticks was extracted. DNA samples were tested using real-time PCR for Rickettsia spp. infections. The species of Rickettsia in positive samples were determined using gltA gene amplification and sequencing. A total of 250 ticks were collected from 50 stray dogs and all of them belonged to Rhipicephalus sanguineus sensu lato. Totally, 10 pooled of 50 pooled ticks were positive for Rickettsia spp. in real-time PCR and the minimal Rickettsial infection rate was 4% in this study. The identified Rickettsia spp. included R. massiliae (n = 5), R. rhipicephali (n = 1), and R. sibirica (n = 1). In this study, molecular evidence of Rickettsia spp. infection was observed in collected ticks from stray dogs in southeast Iran. More sensitivity to human and animal health care systems in southeastern Iran is essential to the diagnosis of suspected clinical cases that are related to rickettsiosis. 相似文献
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