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M. Imöhl R. R. Reinert P. M. Tulkens M. van der Linden 《European journal of clinical microbiology & infectious diseases》2014,33(11):2035-2040
Continuous nationwide surveillance of invasive pneumococcal disease (IPD) was conducted in Germany. From July 1, 1997, to June 30, 2013, data on penicillin susceptibility were available for 20,437 isolates. 2,790 of these isolates (13.7 %) originate from patients with meningitis and 17,647 isolates (86.3 %) are from non-meningitis cases. A slight decline in isolates susceptible at 0.06 and 0.12 μg/ml can be noticed over the years. Overall, 89.1 % of the isolates had minimum inhibitory concentrations (MICs) of ≤0.015 μg/ml. In 2012/2013, the first three isolates of Streptococcus pneumoniae with MICs of 8 μg/ml were found. The application of different guidelines with other MIC breakpoints for the interpretation of penicillin resistance leads to differences in susceptibility categorisation. According to the pre-2008 Clinical and Laboratory Standards Institute (CLSI) interpretive criteria, 5.3 % of isolates overall were intermediate and 1.4 % were resistant to penicillin. Application of the 2008–2014 CLSI interpretive criteria resulted in 7.6 % resistance among meningitis cases and 0.5 % intermediate resistance in non-meningitis cases. Referring to the 2009–2014 European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints, 7.6 % of the isolates in the meningitis group were resistant to penicillin. In the non-meningitis group, 6.1 % of the isolates were intermediate and 0.5 % were resistant. These differences should be kept in mind when surveillance studies on pneumococcal penicillin resistance are compared. 相似文献
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Vaccinia‐based influenza vaccine overcomes previously induced immunodominance hierarchy for heterosubtypic protection
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Ji‐Sun Kwon Jungsoon Yoon Yeon‐Jung Kim Kyuho Kang Sunje Woo Dea‐Im Jung Man Ki Song Eun‐Ha Kim Hyeok‐il Kwon Young Ki Choi Jihye Kim Jeewon Lee Yeup Yoon Eui‐Cheol Shin Jin‐Won Youn 《European journal of immunology》2014,44(8):2360-2369
Growing concerns about unpredictable influenza pandemics require a broadly protective vaccine against diverse influenza strains. One of the promising approaches was a T cell‐based vaccine, but the narrow breadth of T‐cell immunity due to the immunodominance hierarchy established by previous influenza infection and efficacy against only mild challenge condition are important hurdles to overcome. To model T‐cell immunodominance hierarchy in humans in an experimental setting, influenza‐primed C57BL/6 mice were chosen and boosted with a mixture of vaccinia recombinants, individually expressing consensus sequences from avian, swine, and human isolates of influenza internal proteins. As determined by IFN‐γ ELISPOT and polyfunctional cytokine secretion, the vaccinia recombinants of influenza expanded the breadth of T‐cell responses to include subdominant and even minor epitopes. Vaccine groups were successfully protected against 100 LD50 challenges with PR/8/34 and highly pathogenic avian influenza H5N1, which contained the identical dominant NP366 epitope. Interestingly, in challenge with pandemic A/Cal/04/2009 containing mutations in the dominant epitope, only the group vaccinated with rVV‐NP + PA showed improved protection. Taken together, a vaccinia‐based influenza vaccine expressing conserved internal proteins improved the breadth of influenza‐specific T‐cell immunity and provided heterosubtypic protection against immunologically close as well as distant influenza strains. 相似文献
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So Jin Bing Min Ju Kim Ginnae Ahn Jaehak Im Dae Seung Kim Danbee Ha Jinhee Cho Areum Kim Youngheun Jee 《Acta histochemica》2014
Owing to its susceptibility to radiation, the small intestine of mice is valuable for studying radioprotective effects. When exposed to radiation, intestinal crypt cells immediately go through apoptosis, which impairs swift differentiation necessary for the regeneration of intestinal villi. Our previous studies have elucidated that acidic polysaccharide of Panax ginseng (APG) protects the mouse small intestine from radiation-induced damage by lengthening villi with proliferation and repopulation of crypt cells. In the present study, we identified the molecular mechanism involved. C57BL/6 mice were irradiated with gamma-rays with or without APG and the expression levels of apoptosis-related molecules in the jejunum were investigated using immunohistochemistry. APG pretreatment strongly decreased the radiation-induced apoptosis in the jejunum. It increased the expression levels of anti-apoptotic proteins (Bcl-2 and Bcl-XS/L) and dramatically reduced the expression levels of pro-apoptotic proteins (p53, BAX, cytochrome c and caspase-3). Therefore, APG attenuated the apoptosis through the intrinsic pathway, which is controlled by p53 and Bcl-2 family members. Results presented in this study suggest that APG protects the mouse small intestine from irradiation-induced apoptosis through inhibition of the p53-dependent pathway and the mitochondria/caspase pathway. Thus, APG may be a potential agent for preventing radiation induced injuries in intestinal cells during radio-therapy such as in cancer treatment. 相似文献
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Jung Min Moon Eun Ae Kang Kyungdo Han Seung Wook Hong Hosim Soh Seona Park Jooyoung Lee Hyun Jung Lee Jong Pil Im Joo Sung Kim 《World journal of gastroenterology : WJG》2020,26(4):404-415
BACKGROUND The incidence of inflammatory bowel disease(IBD)is increasing in Asia.Numerous risk factors associated with IBD development have been investigated.AIM To investigate trends and environmental risk factors of Crohn’s disease(CD)diagnosed in persons aged≥40 years in South Korea.METHODS Using the National Health Insurance Service database,a total of 14060821 persons aged>40 years who underwent national health screening in 2009 were followed up until December 2017.Patients with newly diagnosed CD were enrolled and compared with non-CD cohort.CD was identified according to the International Classification of Diseases 10th revision and the rare/intractable disease registration program codes from the National Health Insurance Service database.The mean follow-up periods was 7.39 years.Age,sex,diabetes,hypertension,smoking,alcohol consumption,regular exercise,body mass index,anemia,chronic kidney disease(CKD)and dyslipidemia were adjusted for in the multivariate analysis model.RESULTS During the follow-up,1337(1.33/100000)patients developed CD.Men in the middle-aged group(40-64 years)had a higher risk than women[adjusted hazard ratio(aHR)1.46,95%confidence interval(CI):1.29-1.66];however,this difference tended to disappear as the age of onset increases.In the middle-aged group,patients with a history of smoking[(aHR 1.46,95%CI:1.19-1.79)and anemia(aHR 1.85,95%CI:1.55-2.20)]had a significantly higher CD risk.In the elderly group(age,≥65 years),ex-smoking and anemia also increased the CD risk(aHR 1.68,95%CI:1.22-2.30)and 1.84(95%CI:1.47-2.30,respectively).Especially in the middle-aged group,those with CKD had a statistically elevated CD risk(aHR 1.37,95%CI:1.05-1.79).Alcohol consumption and higher body mass index showed negative association trend with CD incidence in both of the age groups.[Middle-aged:aHR 0.77(95%CI:0.66-0.89)and aHR 0.73(95% CI:0.63-0.84),respectively][Elderly-group:aHR 0.57(95% CI:0.42-0.78)and aHR 0.84(95%CI 0.67-1.04),respectively].For regular physical activity and dyslipidemia,negative correlation between CD incidences was proved only in the middle-aged group[aHR 0.88(95%CI:0.77-0.89)and aHR 0.81(95%CI:0.68-0.96),respectively].CONCLUSION History of cigarette smoking,anemia,underweight and CKD are possible risk factors for CD in Asians aged>40 years. 相似文献
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Oral Diseases (2012) 18, 537–547 Objective: The human periodontal ligament stem cells (hPDLSCs) and human alveolar bone–derived stromal cells (hABCs) seem to be closely involved in the maintenance of alveolar bone in an anatomically indirect manner; however, there is little study on this matter. Therefore, the effect of hPDLSCs on the osteoclastogenic, osteogenic, and adipogenic differentiation of hABCs was evaluated, focusing on the humoral factors released by hPDLSCs. Materials and methods: Human periodontal ligament stem cells and hABCs were isolated and characterized. hPDLSCs were indirectly cocultured to observe the in vitro effect of humoral factors released from hPDLSCs on the osteoclastogenic, osteogenic, and adipogenic differentiation of hABCs. Human gingival fibroblasts (hGFs) were utilized as positive control. Results: Isolated cells demonstrated the presence of stem cells within. Indirect coculture of hPDLSCs greatly inhibited osteoclastogenesis by hABCs. Osteogenesis/adipogenesis of hABCs was also inhibited by indirect coculture with hPDLSC. The magnitude of regulatory effect from hPDLSCs was significantly greater than that of hGFs. Conclusions: Humoral factors released from hPDLSCs seemed to modulate the differentiation of hABCs, and the osteoclastogenic, osteogenic, and adipogenic differentiation of hABCs was all inhibited, suggesting the potential role of hPDLSCs in the maintenance of the alveolar bone. 相似文献