油溶纳米蜂胶液联合两种根充糊剂对感染根管常见菌的体外抑菌性研究

目的探讨蜂胶类根充糊剂对感染根管常见菌的体外抑菌作用。方法选择感染根管的6种常见菌为实验菌种,琼脂扩散法观察蜂胶类根充糊剂的抗微生物作用;建立体外根管粪肠球菌感染模型,评价蜂胶类根充糊剂在离体牙根管内的抗粪肠球菌作用。结果蜂胶类根充糊剂对实验的各种细菌均具有抑菌作用,除油溶纳米蜂胶氢氧化钙甘油糊剂对粪肠球菌和具核梭杆菌的抑菌作用小于对照组外,其他实验组与对照组相比均增强了(P0.05或P0.01)或并未减弱(P0.05)原始糊剂的抑菌效果,糊剂中水溶蜂胶加入后短期内的抑菌作用优于油溶纳米蜂胶。结论蜂胶类根充糊剂对感染根管常见菌具有良好的抑菌效果,将其用作根管充填的材料具有一定的应用前景。     

壳聚糖-纳米羟基磷灰石复合制剂对粪肠球菌抗菌作用的体外研究

目的观察壳聚糖一纳米羟基磷灰石（CS／nHA）复合制剂对粪肠球菌生物膜的体外抗菌作用,为研究该药物对根管内粪肠球菌生物膜抗菌的作用打下基础,探索激光共聚焦显微镜（CLSM）技术在研究生物膜领域中的优势。方法采用液体二倍稀释法,测定壳聚糖／纳米羟基磷灰石复合制剂对游离状态下粪肠球菌的最小抑菌浓度和最小杀菌浓度;将粪肠球菌在体外培养成生物膜后,利用CLSM观察研究该生物膜中细菌活性。结果CS／nHA制剂在0．467mg／mL时对游离状态下的粪肠球菌具有抑菌和杀菌作用,与对照组相比差异有统计学意义。使用CS／nHA制剂前后粪肠球菌生物膜活菌百分比显著下降,与对照组相比差异有统计学意义（P〈0．05）。结论CS／nHA制剂对粪肠球菌有较强的抗菌作用,将其作为根管封闭剂中的抗菌成分具有一定的应用前景。     

2009-2011年胆石症患者胆汁肠球菌菌群分布及菌种耐药性变迁

目的 了解2009年1月年2011年12月胆石症患者胆汁中肠球菌的分布及菌种耐药性变迁,指导临床合理应用抗菌药物.方法 采用法国生物梅里埃公司生产的VITEK-2细菌分析仪对胆汁标本中分离的肠球菌做鉴定及药敏试验.结果 2009年1月至2010年6月共分离到74株肠球菌;2010年7月至2011年12月共分离到115株肠球菌,排在前两位的均为粪肠球菌和屎肠球菌.药敏结果显示粪肠球菌对除红霉素和喹努普汀/达福普汀外的其他抗菌药物具有较高的抑菌活性;屎肠球菌对除喹努普汀/达福普汀、利奈唑胺、万古霉素外的其他抗菌药物具有较高的耐药率;首次检测到耐利奈唑胺的肠球菌.结论 胆石症患者胆汁中肠球菌感染以粪肠球菌和屎肠球菌为主,且多种细菌对抗菌药物均有不同程度的耐药,因此加强细菌耐药监测对临床合理使用抗菌药物有重要的参考意义.     

铜绿假单胞菌体外抑菌活性研究

目的 观察铜绿假单胞菌抗菌物质对鲍曼不动杆菌等细菌的体外抑菌效果.方法 用交叉条带实验方法检测了铜绿假单胞菌对鲍曼不动杆菌、耐甲氧西林表皮葡萄球菌和粪肠球菌的体外抑制活性.结果 铜绿假单胞菌对鲍曼不动杆菌、耐甲氧西林表皮葡萄球菌和粪肠球菌体外抑菌活性良好,10株铜绿假单胞菌中,有8株对鲍曼不动杆菌的抑制率均达到了100％.另外有8株对耐甲氧西林表皮葡萄球菌的抑菌率均为100％;有6株对粪肠球菌的抑菌率为100％.结论 铜绿假单胞菌对上述3种致病菌具有较强的抗菌活性,具有开发前景.     

血流感染粪肠球菌和屎肠球菌的临床分布及耐药研究

回顾性分析上海市某三甲医院血培养阳性标本中粪肠球菌和屎肠球菌的临床分布及对抗菌药物的耐药特征,为临床治疗其所致感染奠定基础。收集上海市某三甲医院2012年2月—2016年9月血流感染患者血液标本中的粪肠球菌和屎肠球菌,采用法国生物梅里埃公司的VITEK 2Compact全自动细菌鉴定和药敏分析系统进行细菌鉴定及药敏测定,研究细菌临床分布特点及对常用抗菌药物的耐药特征。共分离获得30株粪肠球菌和17株屎肠球菌。粪肠球菌样本主要来自泌尿科、消化科和血液科,所占比例分别为13.33%、16.67%和10.00%。粪肠球菌对青霉素、氨苄西林、环丙沙星、左氧氟沙星、四环素和红霉素的耐药率分别为13.33%、10.00%、36.67%、33.33%、66.67%和60.00%。屎肠球菌样本主要来自消化科(29.41%),其对以上抗菌药物的耐药率分别为88.24%、82.35%、88.24%、76.47%、23.53%和70.59%。屎肠球菌对青霉素、氨苄西林、环丙沙星和左氧氟沙星的耐药率显著高于粪肠球菌,而对四环素的耐药率显著低于粪肠球菌。两者均对替加环素、利奈唑胺和万古霉素敏感,但万古霉素对屎肠球菌的最低抑菌浓度显著低于粪肠球菌。结果提示,屎肠球菌对青霉素、氨苄西林、环丙沙星、左氧氟沙星的耐药率高于屎肠球菌,对万古霉素敏感,且其万古霉素最低抑菌浓度低于粪肠球菌。本研究为治疗这两种细菌所致感染的经验性用药提供了数据支持。     

苏木对粪肠球菌体外抑菌试验及其对毒力因子cylA、efaA、gelE转录表达抑制作用的初探

目的研究苏木体外对粪肠球菌的抑菌效果,并初步研究其抑菌作用是否为通过影响或干扰某些毒力因子的表达而实现的。方法采用常量肉汤稀释法确定苏木体外对粪肠球菌的最小抑菌浓度(MIC),以此判断抑菌效果,然后用RT-PCR方法检测粪肠球菌毒力因子cylA、gelE和efaA受苏木作用后的表达水平的变化。结果苏木对粪肠球菌的最小抑菌浓度为5 mg/mL,RT-PCR结果表明,毒力因子efaA、gelE的表达水平随着药物浓度的梯度增加而降低,在浓度为5 mg/mL及更高时mRNA的表达水平受到完全抑制。结论苏木体外对粪肠球菌起到了抑制作用,并对本实验所选毒力因子efaA、gelE的表达过程产生了抑制作用。     

医院内感染的肠球菌和肠道中的肠球菌耐药性差异的研究

目的 研究临床分离的院内感染的肠球菌对常用抗生系的耐药性及与健康人肠道中的肠球菌的耐药性比较。方法 应用琼脂稀释法检测从临床分离的５２株肠球菌和健康人肠道中分离的肠球菌的最低抑菌浓度（ＭＩＣ）。结果 肠球菌对临床常用的１１种抗生素的耐药性以万古霉素最低,ＭＩＣ５０为２,ＭＩＣ９０为４。屎肠球菌和粪肠球菌的耐药性对万古霉素有明显差异。院内感染分离的肠球菌和健康人肠道中的肠球菌的耐药性亦有显著的差异。     

2004-2006年肠球菌属临床耐药性分析

调查了2004～2006年肠球菌对临床常用抗菌药物的耐药性,为临床合理治疗肠球菌感染提供理论依据.用Kirby-Bauer纸片扩散法进行药敏试验.屎肠球菌所占的比例已经超过粪肠球菌,成为肠球菌属中最常见的致病菌,并且呈现逐年上升趋势.粪肠球菌对青霉素和氨苄西林的耐药率分别从2004年的42.1%和32.8%下降至2006年的20.7%和15.8%.糖肽类药物对肠球菌属依然保持高度敏感.监测肠球菌的耐药性变化,对于治疗和控制肠球菌感染具有重要的意义.     

引起院内感染的肠球菌和肠道中的肠球菌耐药性差异的研究

目的　研究临床分离的院内感染的肠球菌对常用抗生素的耐药性及与健康人肠道中的肠球菌的耐药性比较。方法　应用琼脂稀释法检测从临床分离的５２ 株肠球菌和健康人肠道中分离的肠球菌的最低抑菌浓度（ＭＩＣ） 。结果　肠球菌对临床常用的１１ 种抗生素的耐药性以万古霉素最低,ＭＩＣ５０ 为２ ,ＭＩＣ９０ 为４ 。屎肠球菌和粪肠球菌的耐药性对万古霉素有明显差异。院内感染分离的肠球菌和健康人肠道中的肠球菌的耐药性亦有显著的差异。结论　肠球菌对抗生素的敏感性以万古霉素最敏感,肠球菌应鉴定到种的水平以便更好地监控抗生素的耐药性。     

两种根管冲洗液对狗牙根管内细菌抗菌作用的实验研究

目的观察2%洗必泰溶液和3%双氧水2种根管冲洗液对狗牙根管内粪肠球菌、溶血链球菌、微小消化链球菌、中间普氏菌及具核酸杆菌的影响,为临床根管治疗提供参考。方法选择成年健康杂种狗3只,共有24个实验牙,48个实验牙根。于狗牙根管内接种粪肠球菌、溶血链球菌、微小消化链球菌、中间普氏菌及具核酸杆菌。对狗牙完成根管治疗。于治疗后12个月拍摄根尖X线片,并记录牙齿和根尖周组织的临床表现。将患牙随机分为3组,每组7颗患牙,去除根管内充填物并进行根管预备,实验一组用2%洗必泰溶液冲洗根管,实验二组用3%双氧水冲洗根管,对照组用0.9%NaC l溶液冲洗根管。分别在根管预备前及根管预备冲洗后对根管内细菌取样,培养,鉴定并记录细菌菌落数量,测定根管内细菌变化情况。结果根管预备冲洗后3组根管内的细菌量均较根管预备前显著下降（P〈0.05）。2%洗必泰溶液和3%双氧水2种根管冲洗液的杀菌效果明显好于0.9%NaC l溶液（P〈0.05）,2%洗必泰溶液明显好于3%双氧水（P〈0.05）。结论2%洗必泰溶液是有效的根管冲洗药物,可明显减少狗牙根管内粪肠球菌、溶血链球菌、微小消化链球菌、中间普氏菌及具核酸杆菌的数量,但不能完全清除根管内的细菌。     

In vitro activity of sodium benzoate against clinically relevant Enterococcus faecalis and Enterococcus faecium isolates

The antimicrobial effects of sodium benzoate against Enterococcus faecalis and Enterococcus faecium were investigated. The MIC(90) of sodium benzoate were 64 mg/L for E. faecalis and 32 mg/L for E. faecium, while the MBC(90) were 128 mg/L and 64 mg/L, respectively. Although further studies are required for clinical evidence, sodium benzoate seems to be effective against Enterococcus spp.     

The inhibitory activity of typified propolis against Enterococcus species

Propolis, a natural bee product widely used for its antimicrobial activity, was tested against isolates of Enterococcus from humans, pig-tailed macaques, isolates of refractory endodontic treatment cases, and isolates from Lactobacillus-containing food supplements. Typification of the propolis was performed by high-performance liquid chromatography (HPLC) by which prenylated compounds, cinnamic acid derivatives, and flavonoids were detected as the main constituents. Minimum inhibitory concentrations (MIC) were determined using the agar dilution method. All human and animal Enterococcus isolates demonstrated MIC values of 1600 microg/mL. Enterococcal species of human and animal origin were inhibited by propolis. Particularly, human isolates of E. faecium and E. faecalis of refractory endodontic treatment cases were susceptible to propolis of Brazilian origin.     

Antibacterial activity of crude methanolic extract and its fractions of aerial parts of Anthemis tinctoria

The antibacterial activity of the methanolic extract and its fractions of aerial parts of Aniheinis tinctoria (Asteraceae) was investigated against representative gram-positive Staphylococcus aureus (ATCC 25923) and Enterococcus faecalis (ATCC 29212) and gram-negative strains Escherichia coli (ATCC 25922) and Pseudomonas aeruginosa (ATCC 27853). The activity was concentrated mainly in the dichloromethane (DCM) and hexane fractions of crude methanolic extract. The 5 mg of DCM extract per disk produced 15-16 mm of inhibition zone against S. aureus and P. aeruginosa, however, no activity was found against E. faecalis and E. coli. The hexane fraction showed activity against S. aureus, P. aeruginosa and E. faecalis. As DCM fraction showed the highest antibacterial activity in the disk diffusion assay, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of only this fraction was determined against S. aureus and P. aeruginosa. These values were found to be in the range of 1.25 to 10 mg/ml.     

三种根管充填材料对乳牙根尖周炎常见细菌的抑菌性

目的 评估和比较3种乳牙根管充填材料对乳牙根尖周炎常见细菌的抗菌功效。方法 在体外实验中,采用纸片扩散法检测并观察3种乳牙根管充填材料及蒸馏水作用于粪肠球菌、牙龈卟啉单胞菌和具核梭杆菌后形成的抑菌环直径（mm）,用SPSS 24.0软件进行统计分析。结果 三重抗生素糊剂对乳牙根尖周炎根管中3种细菌均显示出最强的抗菌潜力,其次是Vitapex®、氢氧化钙糊剂,结果差异具有统计学意义（P<0.05）;蒸馏水对3种细菌是非抑制性的。粪肠球菌对3种药物反应最敏感,其次是牙龈卟啉单胞菌、具核梭杆菌,结果差异具有统计学意义（P<0.05）。结论 三重抗生素糊剂是最推荐用于治疗乳牙根尖周炎的根管充填材料。     

伊犁黑蜂蜂胶对不同生长状态白假丝酵母菌抑菌作用的体外研究

目的探究伊犁黑蜂蜂胶对白假丝酵母菌游离状态及其生物膜状态的影响。方法采用NCCLS M27-A2酵母微量稀释法结合平板法测定蜂胶对游离状态下白假丝酵母菌的最小抑菌浓度(MIC)和最低杀菌浓度(MBC);玻片法在体外构建白假丝酵母菌生物膜模型,采用MTT法检测蜂胶对白假丝酵母菌生物膜状态下的最低生物膜清除浓度(MBEC)及抑制作用;激光共聚焦显微镜(CLSM)观察不同浓度蜂胶醇提取物对同一时间白假丝酵母菌生物膜的抑菌效果,并进行红蓝荧光染色定量分析。结果伊犁黑蜂蜂胶对浮游白假丝酵母菌的MIC为4mg/mL,MBC为8mg/mL;伊犁黑蜂蜂胶对生物膜状态下白假丝酵母菌的MBEC为16mg/mL,随着药物浓度的增加抑菌性逐渐增大,差异具有统计学意义(P0.05);CLSM观察,伊犁黑蜂蜂胶作用于白假丝酵母菌生物膜后可使生物膜内活菌比例降低,生物膜活性减弱,生物膜内实验菌死亡率随蜂胶浓度增加呈上升趋势,与阴性对照组比较差异有统计学意义(P0.05)。结论伊犁黑蜂蜂胶在体外对不同状态下的白假丝酵母菌均起到了明显的抑制作用。     

Recovery of Enterococcus faecalis in root canal lumen of patients with primary and secondary endodontic lesions

The presence of Enterococcus faecalis in root canal teeth affected by primary and secondary periapical lesions was studied using polymerase chain reaction (PCR) assays. The association between presence of E. faecalis with clinical signs of apical lesions was assessed to evaluate a possible relationship between clinical findings. Microbial samples were obtained from healthy patients affected by different periapical lesions, 79 teeth with primary periapical lesion and 23 with secondary periapical lesion. For each tooth, clinical symptoms and X-ray appearance were examined. E. faecalis was detected in 6 of 79 samples with primary lesion (7.6%), and in 9 of 23 with secondary lesion (39.1%). Suggested association was found between E. faecalis and secondary apical lesions. As regard specific signs and symptoms E. faecalis was more associated with asymptomatic lesions (all p<0.05) than with symptomatic apical lesions. The study confirms the high presence of E. faecalis in secondary apical lesions. However, its effective role in endodontic pathogenesis such as bone periapical lesions needs to be clarified.     

Antibacterial and cytotoxic activity of Brazilian plant extracts--Clusiaceae

Twelve extracts obtained from nine plants belonging to six different genera of Clusiaceae were analyzed against Gram-negative (Escherichia coli and Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus and Enterococcus faecalis) bacteria using the microdilution broth assay. Tovomita aff. longifolia, T. brasiliensis, Clusia columnaris, Garcinia madruno, Haploclathra paniculata, and Caraipa grandifolia extracts showed significant results against the bacteria. The organic extract obtained from the leaves of T. aff. longifolia showed minimal inhibitory concentration (MIC) = 70 microg/ml and minimal bactericidal concentration (MBC) = 90 microg/ml against E. faecalis and the organic extract made with the stem of C. columnaris showed MIC = 180 microg/ml and MBC = 270 microg/ml against P. aeruginosa. None of the antibacterial extracts showed lethal activity against brine shrimp nauplii. On the other hand, both aqueous and organic extracts obtained from the aerial organs of Vismia guianensis that were cytotoxic to brine shrimp nauplii did not show a significant antibacterial activity in the assay.