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ObjectiveDental plaque is a causative factor for oral disease and a potential reservoir for respiratory infection in the elderly. Therefore, there is a critical need for the development of effective methods to remove oral biofilm. The objective of this study was to investigate the effect of proteases on oral biofilm formation andremoval.DesignThe in vivo effect of actinidin, a cysteine protease, on the removal of tongue coating was assessed after orally taking a protease tablet. Effects of the proteases trypsin, papain and actinidin on Actinomyces monospecies biofilm and multispecies biofilm that was reconstructed using a plaque sample from the tongue coating were investigated using the microtiter plate method. Antimicrobial tests and limited proteolysis of fimbrial shaft proteins were also performed to clarify underlying mechanisms of oral biofilm removal.ResultsTablets containing actinidin removed tongue coating in elderly subjects. Oral Actinomyces biofilm was significantly reduced by the proteases papain, actinidin and trypsin. Papain and trypsin effectively digested the major fimbrial proteins, FimP and FimA, from Actinomyces. Actinidin, papain and trypsin reduced multispecies biofilm that was reconstructed in vitro. Papain and trypsin inhibited formation of multispecies biofilm in vitro.ConclusionsThis study shows that proteases reduced oral biofilm in vivo in elderly subjects and in vitro, and suggests that protease digests fimbriae and inhibits biofilm formation. 相似文献
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Geeta Ramesh Juan T Borda Amy Gill Erin P Ribka Lisa A Morici Peter Mottram Dale S Martin Mary B Jacobs Peter J Didier Mario T Philipp 《Journal of neuroinflammation》2009,6(1):23-16
Background
Lyme neuroborreliosis (LNB) may present as meningitis, cranial neuropathy, acute radiculoneuropathy or, rarely, as encephalomyelitis. We hypothesized that glia, upon exposure to Borrelia burgdorferi, the Lyme disease agent, produce inflammatory mediators that promote the acute cellular infiltration of early LNB. This inflammatory context could potentiate glial and neuronal apoptosis. 相似文献68.
目的探讨天津地区结核分枝杆菌临床分离株分子流行病学特征。方法连续收集天津市海河医院2005年8月16日~11月25日就诊病人痰培养阳性的结核分枝杆菌100株,采用间隔区寡核苷酸分型(Spoligotyping)和数目可变串联重复序列(VNTR)两种方法进行基因分型,并运用软件对二者的结果进行分析。依据北京分化支的定义。运用多重和实时定量PCR方法将其区分为W菌/典型北京家族菌株和非典型北京菌株,x^2检验分析两种亚群与患者年龄和耐药性之间的联系。结果排除污染菌株,共对96株结核分枝杆菌临床分离株进行两种方法的基因分型,Spoligotyping结果为91.7%为北京基因型(含3株类北京基因型)结核分枝杆菌(88/96)。VNTR分型可将北京基因型分为60种基因型。在北京分化支结核分枝杆菌中,W菌/典型北京家族菌株占93.2%(82/88)。两种北京分化支亚群与患者年龄和耐药性没有显著性统计学差异(P〉0.05)。结论天津地区结核病患者临床分离的结核分枝杆菌中,北京基因型呈现较为明显的优势。VNTR的分辨率明显高于Spoligotyping。北京分化支的两种亚群在天津地区临床结核病患者中均存在流行,但以W菌/典型北京家族菌株为主。 相似文献
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Anne-Marie Kerttula Outi Lyytikäinen Minna Kardén-Lilja Salha Ibrahem Saara Salmenlinna Anni Virolainen Jaana Vuopio-Varkila 《BMC infectious diseases》2007,7(1):94
Background
In Finland, the annual number of MRSA notifications to the National Infectious Disease Register (NIDR) has constantly increased since 1995, and molecular typing has revealed numerous outbreak isolates of MRSA. We analyzed the data on MRSA notifications of the NIDR, and MRSA isolates were identified mainly by pulsed-field gel electrophoresis (PFGE) at the National Reference Laboratory (NRL) in Finland during 1997–2004. One isolate representative of each major PFGE type was further characterized by multilocus sequence (MLST)-, staphylococcal cassette chromosome mec (SCCmec)-, and Panton-Valentine leukocidin (PVL)-typing. 相似文献70.
《Vaccine》2015,33(22):2584-2593
BackgroundThere is currently a re-focus at the global level on the importance of the home-based record within vaccination service delivery as an important information resource but there are few reports of ever and current home-based record prevalence across countries.MethodsWe considered all Demographic and Health Surveys (starting with DHS round 3) conducted between 1993 and 2013 for which a final dataset was available in the public domain at the time of the analysis. Ever and current prevalence of home-based records for recording vaccination was estimated for children aged 12–23 months at the time of the survey through a secondary analysis of data from 180 Demographic and Health Surveys conducted in 67 countries derived from questions asked of women aged 15–49 years for their children on home-based record availability and retention. Ever home-based record prevalence is the proportion of children aged 12–23 months who have ever received a home-based record. Current home-based record prevalence is the proportion of children aged 12–23 months for whom a home-based record was available for viewing by the surveyor at the time of the survey.ResultsEstimated ever home-based record prevalence was ≥90% in 116 surveys from 52 countries and was <70% in 15 surveys from 7 countries. Estimated current home-based record prevalence was ≥80% in 31 surveys from 23 countries and was <50% in 51 surveys from 24 countries. Current home-based record prevalence was <80% as of the most recent survey during 2010–2013 for five (Bangladesh, Ethiopia, Nigeria, Indonesia and Pakistan) of the ten countries with the largest birth cohorts globally. Among 34 countries that conducted three or more DHS, we observed improvements in both ever and current home-based record prevalence of >10% points in six countries. Current home-based record prevalence increased >10% points in six countries where the ever prevalence was maintained at ≥90% across the period of observation. And, no meaningful change was observed in estimated ever and current home-based record prevalence in 11 countries, five of which maintained ever prevalence ≥90% across the period of observation. High home-based record loss rates were observed in many countries.ConclusionsThe results here show that despite improvements in the availability, utilization and retention of home-based records for recording vaccination history in some countries, opportunities remain to change the mind-set in many national immunization programmes around the importance of the home-based record, particularly in countries with large birth cohorts. Immunization programmes are encouraged to monitor ever and current home-based record prevalence. Nationally representative household surveys collecting information on immunization coverage should include ever and current home-based record prevalence in the standard survey reports and tables to better enable programme managers to identify problems and target corrective action. 相似文献