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1.
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   
2.
Specific immunoglobulin G antibody for severe acute respiratory syndrome (SARS) coronavirus was detected in maternal blood, umbilical blood, and amniotic fluid from a pregnant SARS patient. Potential protection of fetus from infection was suggested.  相似文献   
3.
《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   
4.
《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   
5.
《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   
6.
7.
《Vaccine》2018,36(4):572-577
ObjectiveTo identify a potential nadir of the impact of pneumococcal conjugate vaccination (PCV) in infancy on invasive pneumococcal diseases (IPD) in children under 16 in Germany.MethodsActive surveillance on IPD based on two independent data sources with capture-recapture correction for underreporting. Annual incidence rates by age group, serotypes, site of infection, and relative incidence reduction compared to pre-vaccination period (1997–2001) at nadir and for the most recent season are reported. We calculated vaccine coverage at the age of 24 months using health insurance claims data.Results96–97% of children had received at least two doses of PCV since 2009. The maximum impact on overall IPD incidence was achieved in 2012/13 (−48% [95% CI: −55%; −39%]) with a rebound to −26% [95% CI: −36%; −16%] in 2015/16. Non-PCV13 serotypes accounted for 84.1% of the IPD cases in 2015/16. The most frequent non-PCV serotypes in IPD in 2014/15 and 2015/16 were 10A, 24F, 15C, 12F, 38, 22F, 23B, and 15B. The impact at nadir was highest in children 0–1 years of age both in meningitis and non-meningitis cases, whereas the impact for other age groups was higher for meningitis cases. The rebound mainly pertained to non-meningitis cases.ConclusionThe maximum impact of pneumococcal conjugate vaccination has been attained and signs of a rebound are apparent. Sustained surveillance for IPD in children is warranted to assess whether these trends will continue. There may be a need for vaccines using antigens common to all serotypes.  相似文献   
8.
《Vaccine》2018,36(4):491-497
BackgroundThe present study aimed to estimate residents’ willingness to accept a future H7N9 vaccine and its determinants in the general adult population in Beijing, China.MethodsWe conducted a multi-stage sampling, cross-sectional survey using self-administered anonymous questionnaires from May to June, in 2014. The main outcome variable was residents’ willingness to accept a future H7N9 vaccine. Logistic regression was used to identify the predictors of vaccination willingness.ResultsOf the 7264 eligible participants, 14.5% of Beijing residents reported that they had not heard of H7N9. Among those who had heard of H7N9, 59.5% of the general adult population would be willing to accept a future H7N9 vaccine, and approximately half of them reported ‘I am afraid of being infected by H7N9’ and ‘H7N9 vaccine can prevent infections’, and 28.1% reported ‘my daily life is affected by H7N9’. The variables that were significantly associated with a higher likelihood of reporting willingness were being younger adults (aged 18–29 years: OR = 1.52, 95% CI: 1.17–1.97; aged 30–39 years: OR = 1.39, 95% CI: 1.08–1.78), being farmers (OR = 1.61; 95% CI: 1.32–1.96), being unemployed people (OR = 1.36; 95% CI: 1.04–1.78), living in suburban areas (OR = 2.18; 95% CI: 1.89–2.51), having ≥2 children in the family (OR = 1.41; 95% CI: 1.03–1.92), perceived risk in China (OR = 1.30; 95% CI: 1.15–1.48), perceived susceptibility to disease (OR = 3.13; 95% CI: 2.73–3.58), perceived negative effect on daily life (OR = 1.32; 95% CI: 1.13–1.55), perceived effectiveness of vaccination (OR = 2.34; 95% CI: 2.07–2.64), and recent uptake of influenza vaccine (OR = 2.26; 95% CI: 1.92–2.66).ConclusionsA great number of Beijing residents had doubts about the vaccine’s effectiveness and were not concerned about disease risk, which were the factors affecting willingness to be vaccinated. Targeted education programs on disease risk as well as vaccine’s effectiveness are needed to improve the willingness of vaccination for potential H7N9 pandemic preparedness.  相似文献   
9.
目的 了解北京市昌平区食源性单增李斯特菌(Lm)的毒力基因携带情况、抗生素敏感性及分子特征。方法 对2010-2016年12类食品中分离的22株Lm进行血清型、毒力基因、抗生素敏感性、多位点序列分型(MLST)和脉冲场凝胶电泳(PFGE)分析。结果 22株Lm分为5种血清型(以1/2c、3a血清型为主);19种毒力基因携带谱(T1~T19),毒力基因阳性数为6~12个;对氨苄西林、青霉素、美罗培南、复方新诺明、万古霉素和环丙沙星敏感,出现对四环素、红霉素耐药菌株;分为8个序列型(ST)(包括7个新型STA1~STA7),STA3为主要型别;分为17种PFGE带型,其相似系数为63.5%~100.0%,PTⅠ为主要PFGE带型。结论 昌平区食源性Lm以1/2c、3a血清型为主,STA3为主要型别,PTⅠ为主要PFGE带型,其毒力基因的携带具有差异性,出现对四环素、红霉素耐药株,为食源性Lm的研究提供了参考。  相似文献   
10.
目的分析北京市昌平区2007—2013年艾滋病流行特征,为制定防控措施提供科学依据。方法采用描述性流行病学方法对昌平区2007—2013年艾滋病疫情资料进行分析。结果2007—2013年昌平区共报告HIV/AIDS病例453例,死亡15例,年均发病率为5.63/10万。发病年龄以20~39岁为主,共报告332例,占总病例数的73.29%;男性415例,女性38例,男女性别比为10.92∶1;病例职业以家政、家务及待业居首位,占27.15%(123例),其次为干部职员占13.91%(63例)、商业服务占12.80%(58例)。结论昌平区2007—2013年艾滋病疫情总体呈上升趋势,发病以20~39岁的青壮年男性为主,今后应建立健全艾滋病防控体系,全面落实艾滋病防控措施。  相似文献   
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