再治疗根管粪肠球菌毒力因子gelE表达与临床表现的关系研究

目的:比较再治疗根管内粪肠球菌(enterococcus faecalis)毒力因子gelE表达情况,分析gelE表达与临床表现的关系。方法:采集临床需要根管再治疗病例的根管内细菌样本53例,利用Real Time Quantitative PCR技术来检测gelE的表达情况。统计学分析gelE表达与患者临床表现之间的关系。结果:再治疗根管内粪肠球菌毒力因子gelE在有临床症状或体征和有根尖暗影的病例中表达增强(P<0.05)。结论:再治疗根管内粪肠球菌毒力因子gelE的表达增强与临床症状或体征的出现有关系。     

Antibacterial substantivity of a new antibiotic‐based endodontic irrigation solution

The aim of this study was to evaluate the residual antibacterial activity of Tetraclean, MTAD and 5.25% sodium hypochlorite (NaOCl) in bovine root dentin in vitro. One hundred and ten dentin tubes prepared from bovine incisor teeth were infected in vitro for 14 days with Enterococcus faecalis. Thereafter, the specimens were divided into five groups as follows: Tetraclean; MTAD; 5.25% NaOCl; infected dentin tubes (positive control); and sterile dentin tubes (negative control). Dentin chips were collected using round burs into tryptic soy broth and after culturing, the number of colony‐forming units (CFU) was counted. The number of CFU in all experimental groups was minimum after treatment, and the results obtained were significantly different from each other at any time period (P < 0.05). The Tetraclean group showed the most effective antibacterial action at all five experimental periods (P < 0.05). MTAD group showed the least antibacterial activity after treatment. However, at days 7, 14, 21 and 28 MTAD showed more effective antibacterial action than NaOCl. In each group, the number of CFU increased significantly by time‐lapse (P < 0.05). In conclusion, the residual antibacterial activity of Tetraclean was significantly greater than MTAD and 5.25% NaOCl.     

枯草杆菌二联活菌颗粒对厌食症患儿血清神经肽Y和肿瘤坏死因子-α水平影响及疗效

目的探讨枯草杆菌二联活菌颗粒对厌食症患儿血清神经肽Y(NPY)和肿瘤坏死因子-α(TNF-α)水平影响及疗效。方法选取2012年6月~2014年6月在浙江省嘉兴市妇幼保健院儿童厌食症患者86例,采用随机数字表将其分为观察组(43例)和对照组(43例)。两组患儿均予以纠正患儿不良饮食习惯、健胃消食药和葡萄糖酸锌等常规治疗。观察组患儿加用枯草杆菌二联活菌颗粒1.0 g/次,2次/d,温开水冲服。疗程为6周。对照组患儿除不使用枯草杆菌二联活菌颗粒外余治疗基本同观察组。观察并记录两组患儿治疗前和治疗6周后血清NPY和TNF-α水平的变化,并比较其治疗后的临床效果及药物不良反应。结果治疗6周后,两组患儿血清NPY和TNF-α水平[观察组:(45.53±7.82)pg/m L,(10.24±2.74)mmol/L;对照组:(37.39±7.53)pg/m L,(8.19±2.13)mmol/L]较治疗前[观察组:(32.17±5.18)pg/m L,(6.82±1.76)mmol/L;对照组:(32.79±4.23)pg/m L,(7.03±1.54)mmol/L]明显上升(t=2.89、3.12、2.31、2.45,P<0.05或P<0.01),且观察组上升程度较对照组更明显(t=2.19、2.24,P<0.05);同时观察组患儿临床总有效率(93.02%)较对照组(76.74%)更佳(χ2=4.44,P<0.05)。两组患儿治疗中无明显的药物不良反应发生。结论枯草杆菌二联活菌颗粒治疗儿童厌食症的效果较确切,且安全性较好,其作用机制可能与其升高血清NPY和TNF-α水平,提高患儿的食欲密切相关。     

根管预备对粪肠球菌感染根管形成细菌渗漏的影响

目的 建立粪肠球菌感染根管,以探讨离体条件下根管预备对细菌渗漏的影响.方法 将粪肠球菌接种于离体牙所制作的带模拟根尖周组织的根管内,建立320个体外模型(对照组70个,实验组250),分别进行上1/3,上2/3,全长及超长等不同长度的根管预备,于1、7、21、35、49、63 d进行PCR、SEM检测及细菌培养.结果 超长组1d检测到细菌,全长组7d检测到细菌,其余组所有检测时间点均未检测到细菌.结论 本离体实验显示,对于粪肠球菌感染根管,在根管及根管下段未受干扰的情况下,细菌不会轻易穿出根尖孔,当根管下段受到干扰后,细菌会穿出根尖孔造成细菌渗漏.     

新生儿重症监护室5例早产儿肠球菌感染的鉴定及同源性分析

目的对北京协和医院新生儿重症监护室(neonatal intensive care units,NICU)早产儿定植和感染部位、环境及益生菌中分离出的肠球菌进行菌种鉴定及同源性分析。方法收集2017年6月1—10日NICU及益生菌制剂中分离出的肠球菌共11株,用基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)进行菌种鉴定,采用微量肉汤稀释法测定临床常用抗菌药物的最低抑菌浓度(MIC),用多位点序列分型(MLST)及脉冲场凝胶电泳(PFGE)进行菌株同源性分析。结果 11株菌均为粪肠球菌,对氨苄西林、万古霉素、替考拉宁、呋喃妥因、氯霉素、左氧氟沙星、利奈唑胺等抗菌药物均表现为敏感,仅1株菌对四环素和红霉素耐药。11株粪肠球菌经PFGE分为a-d 4个克隆群,MLST分型分别为ST624、ST25、ST40及ST16,PFGE与MLST分型结果一致。结论此次NICU早产儿粪肠球菌定植或感染可能与益生菌制剂的使用及物表定植的粪肠球菌相关。     

腹腔感染病原菌及其耐药性

目的了解腹腔感染病原菌构成及其耐药性,为临床腹腔感染的治疗提供参考依据。方法对某院2011年1月—2013年12月住院患者送检的腹腔感染标本进行菌种鉴定及药物敏感性检测,并将数据输入WHONET5.6软件进行统计分析。结果 15 946份腹腔感染标本分离非重复病原菌810株,培养阳性率5.08%;革兰阴性杆菌485株(59.88%),革兰阳性菌275株(33.95%),真菌50株(6.17%);居前5位的病原菌分别为大肠埃希菌(24.20%)、屎肠球菌(15.06%)、鲍曼不动杆菌(8.89%)、肺炎克雷伯菌(7.66%)和凝固酶阴性葡萄球菌(6.91%)。产超广谱β-内酰胺酶(ESBLs)大肠埃希菌和肺炎克雷伯菌检出率分别为59.18%和32.79%,各种肠杆菌科细菌对亚胺培南仍高度敏感,但对碳青霉烯类耐药的菌株占4.08%~6.67%;多重耐药鲍曼不动杆菌占52.11%(37/71),耐甲氧西林金黄色葡萄球菌(MRSA)占53.57%(15/28),耐甲氧西林凝固酶阴性葡萄球菌(MRCNS)占71.43%(40/56),耐万古霉素屎肠球菌(VRE)占8.26%。结论该院腹腔感染病原菌主要是以大肠埃希菌为代表的革兰阴性菌,屎肠球菌是最常见革兰阳性致病菌,细菌耐药形势严峻。     

VanC型肠球菌与屎肠球菌对常用抗菌药的耐药状况研究

目的：比较VanC型肠球菌及屎肠球菌对常用抗菌药物的敏感性。方法针对56株VanC型肠球菌及299株屎肠球菌,用琼脂二倍稀释法进行药物敏感性分析;检测高水平耐万古霉素屎肠球菌的万古霉素耐药基因型。结果VanC型肠球菌万古霉素最低抑菌浓度（ MIC）众数为4 mg? L－1,未发现对氨苄西林、万古霉素、替考拉宁及利奈唑胺耐药的VanC型肠球菌。屎肠球菌对氨苄西林、左氧氟沙星、红霉素及利福平的耐药率均达85％以上;对万古霉素和替考拉宁的耐药率分别为1．7％和0．7％;未发现对利奈唑胺和替加环素耐药的屎肠球菌。屎肠球菌万古霉素MIC众数为0．5 mg? L－1。5株万古霉素屎肠球菌万古霉素耐药基因均为vanA型。结论屎肠球菌对万古霉素尚保持较高敏感性,万古霉素对VanC型肠球菌最低抑菌浓度较屎肠球菌高。     

Effect of Bacillus subtilis,Enterococcus faecium,and Enterococcus faecalis supernatants on serotonin transporter expression in cells and tissues

BACKGROUND Bacillus subtilis(B.subtilis),Enterococcus faecium(E.faecium),and Enterococcus faecalis(E.faecalis)are probiotics that are widely used in the clinical treatment of irritable bowel syndrome(IBS).Whether the supernatants of these three probiotics can improve gastrointestinal sensation and movement by regulating the serotonin transporter(SERT)expression needs to be clarified.AIM To investigate whether B.subtilis,E.faecium,and E.faecalis supernatants can upregulate SERT expression in vitro and in vivo.METHODS Caco-2 and HT-29 cells were stimulated with probiotic culture supernatants for 12 and 24 h,respectively.A male Sprague-Dawley rat model of post-infectious irritable bowel syndrome(PI-IBS)was established and the rats were treated with phosphate-buffered saline(group A)and three probiotics culture supernatants(groups B,C,and D)for 4 wk.The levels of SERT were detected by quantitative PCR and western blotting.RESULTS The levels of SERT at post-treatment 12 and 24 h were significantly elevated in Caco-2 cells treated with B.subtilis supernatant compared with those in the control group(aP<0.05).Those levels were markedly upregulated in Caco-2 cells stimulated with E.faecium and E.faecalis supernatants at 24 h(aP<0.05).In addition,SERT expression in groups B,C,and D was significantly higher than that in group A in the 2nd wk(aP<0.05).Increased SERT expression was only found in group D in the 3rd wk(aP<0.05).However,there was no significant difference in SERT expression between the groups in the last week(P>0.05).CONCLUSION The supernatants of B.subtilis,E.faecium,and E.faecalis can upregulate SERT expression in intestinal epithelial cells and the intestinal tissues in the rat model of PI-IBS.     

Linezolid in the treatment of vancomycin-resistant Enterococcus faecium in solid organ transplant recipients: report of a multicenter compassionate-use trial

Abstract: Vancomycin‐resistant Enterococcus faecium (VRE) is increasing in incidence in solid organ transplant recipients and has a high (up to 83%) associated mortality rate. Until recently, there have been no consistently effective antimicrobial therapies for VRE infection. Linezolid is a new antibiotic that belongs to the class of oxazolidinones approved by the FDA for the treatment of VRE infections, including those with bacteremia. Here, we report the experience with linezolid in an open‐label, compassionate‐use trial at 53 US centers for the treatment of documented VRE infections in patients with solid organ transplants. Eighty‐five patients with solid organ transplants and documented VRE infections were studied. Blood cultures were positive for VRE in 43 patients, while 42 patients had other, non‐rectal, sites of infection. Fifty‐three patients responded well to treatment, with clinical resolution of the infection (62.4% survival rate). Of these, 47 had documented negative cultures post therapy. The mean duration of therapy for cured patients was 23.5 days. Thirty‐two (37.6%) patients died, 28 due to sepsis and organ failure (32.9% failure rate), and 4 due to unrelated causes. Mortality rates for patients with bacteremia were comparable to mortality rates observed with patients who had positive cultures from other sites. Adverse reactions to linezolid included thrombocytopenia (4.7%), decreased leukocyte count (3.5%), and an increase in blood pressure (1.2%), none of which led to discontinuation of therapy. Linezolid appears to be a safe and effective treatment option for VRE, even in the presence of bacteremia, and may lead to decreased mortality in solid organ transplant recipients with VRE infection.     

乳酸链球菌素联合次氯酸钠对粪肠球菌的体外抗菌作用研究

目的    研究乳酸链球菌素（Nisin）联合次氯酸钠（NaClO）对粪肠球菌的体外抗菌作用。方法    采用微量稀释法测定Nisin和NaClO对悬浮态粪肠球菌的最低抑菌浓度（MIC）和最低杀菌浓度（MBC）;通过微量棋盘法计算分级抑制浓度指数（FICI）以判定两药联合效应;用Time-Kill实验来测定Nisin和NaClO单用或联合使用的杀菌动力学。结果    Nisin的MICNisin单药和MBCNisin单药分别为6、15 μg/mL,NaClO的MICNaClO单药和MBCNaClO单药分别为0.0625%、0.25%。两药联合应用时的FICI为0.504,对粪肠球菌的抗菌作用为相加作用。24 h内的Time-Kill曲线表明,在4 × MIC单药时,Nisin和NaClO分别单独应用12、8 h可完全杀灭粪肠球菌;Nisin与NaClO联合应用时2 × MIC单药即可在12 h后出现杀菌作用,从4 × MIC单药开始,在4 h内达到完全杀灭作用。结论    Nisin对粪肠球菌具有抗菌作用,且呈浓度依赖性。在体外将Nisin与NaClO联合应用时,对粪肠球菌的抗菌作用表现为相加作用,较单独应用时可在更短时间内以更低的浓度显示出杀菌作用。