Bacterial community profiles of endodontic abscesses from Brazilian and USA subjects as compared by denaturing gradient gel electrophoresis analysis

This study compared the bacterial community profiles of the microbiota associated with acute apical abscesses from Brazilian and USA patients using denaturing gradient gel electrophoresis (DGGE). DNA was extracted from purulent exudate aspirates and part of the 16S rRNA gene was amplified by polymerase chain reaction and separated by DGGE. The resulting banding patterns, which were representative of the bacterial community structures in samples from the two locations, were then compared. Distinct DGGE banding patterns were observed from different samples. Ninety-nine bands with distinct positions in the gels were detected, of which 27 were found only in the USA samples and 13 were exclusive to Brazilian samples. Four of the 59 shared bands showed very discrepant findings with regard to prevalence in the two locations. Cluster analysis of DGGE banding profiles showed a great variability in the bacterial populations associated with teeth with abscesses regardless of the geographical location. Two big clusters, one for each location, were observed. Other clusters contained a mixture of samples from the two locations. The results of the present study demonstrated a great variability in the bacterial community profiles among samples. This indicates that the bacterial communities of abscesses are unique for each individual in terms of diversity. The composition of the microbiota in some samples showed a geography-related pattern. Furthermore, several bands were exclusive for each location and others were shared by the two locations and showed great differences in prevalence.     

发菜基因组DNA提取方法比较与分子鉴定研究

目的 以发菜为研究对象比较不同的提取DNA方法,筛选出了一种适合快速提取发菜DNA的方法。方法 分别利用自主研发的硅珠DNA纯化技术、细菌试DNA提取试剂盒和植物DNA提取试剂盒提取发菜基因组DNA。结果 本实验室开发的硅珠DNA提取纯化技术具有快速、无毒以及获得的发菜DNA纯度高等优势。通过PCR扩增和测序得到16S rRNA基因,利用Blast软件进行序列比对,与发菜同源性为99%。结论 本研究研制的发菜基因组DNA提取方法可用于发菜源性的分子鉴定。     

Surgical site abscess caused by Lactobacillus fermentum identified by 16S ribosomal RNA gene sequencing

We report the first case of surgical site abscess caused by Lactobacillus fermentum from a 53-year-old woman with squamous cell carcinoma of the esophagus after transthoracic esophagectomy and neoadjuvant chemoirradiation. 16S rRNA gene sequencing is a useful tool to better characterize the epidemiology and clinical significance of L. fermentum.     

miR-100过表达通过增强AMPK-mTOR-p70S6K信号通路介导的自噬而发挥抗脓毒症作用的研究

目的：探讨miR-100过表达通过增强AMPK-mTOR-p70S6K信号通路介导的自噬,进而发挥抗脓毒症的作用机制研究。方法：利用脂多糖(LPS)刺激大鼠心肌细胞H9C2构建脓毒症体外细胞模型;细胞通过转染miR-100的激动剂或抑制剂使miR-100在细胞内过表达或敲低,并用qRT-PCR检测细胞内miR-100的表达水平的改变;ELISA检测不同细胞处理组上清中炎症因子IL-1β、IL-6和TNF-α的释放;细胞免疫荧光检测LC3蛋白在细胞中的表达;Western blot检测自噬相关蛋白(p62、LC3和beclin-1)和AMPK-mTOR-p70S6K通路相关蛋白(AMPK、p-AMPK、mTOR、p-mTOR、p70S6K和p-p70S6K)的表达。结果：在LPS处理心肌细胞H9C2的脓毒症细胞模型中,细胞上清炎症因子分泌显著增加,细胞自噬增强,炎症增加;而上调miR-100表达能够诱导增强细胞自噬,并且减弱炎症反应;相反,下调miR-100表达减弱了自噬,并且增强了炎症反应;进一步研究发现miR-100能够引起自噬相关信号通路AMPK-mTOR-p70S6K中相关蛋白表达变化。结论：本研究发现miR-100过表达可以通过上调AMPK-mTOR-p70S6K信号通路介导的自噬水平,发挥抗炎作用,进而在脓毒症中发挥保护作用。     

重组酶介导等温扩增技术检测疟原虫方法的建立和评价

目的 建立一种重组酶介导等温扩增技术（RAA）检测疟原虫的方法。方法 针对疟原虫属保守18S小亚基核糖体RNA （18S rRNA）基因设计特异性引物,筛选确定最佳引物对组合并建立疟原虫重组酶介导核酸等温扩增体系。通过该RAA体系检测疟原虫标准质粒、4种疟原虫[恶性疟原虫( Plasmodium falciparum, P.f )、间日疟原虫( P. vivax, P.v)、三日疟原虫( P. malaria, P.m)、卵形疟原虫( P. ovale, Po)]病原体以及其他6种输血传播寄生虫（婴儿利士曼原虫、杜氏利士曼原虫、刚地弓形虫、溶组织阿米巴虫、犬吉氏巴贝西虫、田鼠巴贝虫）,以评估该体系的灵敏度和特异度。 结果 筛选出一组扩增效果较好的引物对,整个RAA体系使用最佳引物对在37 ℃,20 min即可完成扩增,对标准质粒的检测下限为10^-2 copies/μL,恶性疟原虫、间日疟原虫和卵形疟原虫为10² copies/μL,三日疟原虫为10 copies/μL。RAA检测体系未与其他输血传播寄生虫产生交叉反应,特异性良好。应用RAA方法检测外籍学生献血者标本,结果与荧光定量PCR结果一致。结论 成功建立了一种快速、简便和特异的疟原虫RAA检测方法,将会给血液筛查和一些基层偏远医院的临床检测提供很大帮助。     

指纹图谱结合一测多评法评价拟草果质量的研究

目的建立拟草果Amomumparatsao-ko药材的质量评价方法。方法以鼠李柠檬素为参照峰确定共有峰,建立拟草果的HPLC指纹图谱;以鼠李柠檬素为内标,确定鼠李素、3,5-二羟基-7,4’-二甲氧基黄酮的相对校正因子并计算含量,实现一测多评。同时采用外标法测定3种成分的含量,比较计算值和实测值的差异。结果建立了拟草果的HPLC指纹图谱,10批样品相似度均在0.9以上;以鼠李柠檬素为内标建立的鼠李素、3,5-二羟基-7,4’-二甲氧基黄酮的相对校正因子分别为1.300、0.885,重现性良好,10批拟草果样品一测多评法计算值与实测值无显著差异。结论建立的HPLC指纹图谱和一测多评法可用于拟草果的质量评价。     

前S1抗原检测在乙型肝炎诊断中的应用

[目的]通过对乙肝病毒前S1抗原与HBV血清标志物、HBV—DNA检测的对比分析，对乙肝病毒前S1抗原临床意义进行探讨。[方法]用酶联免疫法（ELISA）对乙肝病毒血清标志物和乙肝病毒前S1抗原进行检测；用FQ—PCR荧光定量法进行HBV—DNA检测。[结果]对HBV血清标志物不同组合模式进行分析发现。HBV血清标志物传染性强（HBeAg阳性）的模式中，乙肝病毒前S1检出率90．2％。在HBV血清标志物传染性弱（HBeAg阴性）的模式中，乙肝病毒前S1抗原检出率为15，6％。HBsAg、HBeAg均为阴性的模式中前S1抗原基本上为阴性，同时，在142例前S1为阳性的模板中DNA的阳性率为88．3％。[结论]前S1抗原与HBeAg在很大程度上具有一致性，与HBV的存在与复制密切相关，能够敏感地反映乙型肝炎病毒的复制情况，其阳性可作为HBV复制的一个重要依据和HBV病毒存在的指标。乙肝病毒前S1抗原的检测结果可以帮助对HBV感染作出比较正确判断，可在不具备条件开展HBV—DAN检测的地区开展前S1抗原的检测，为乙型肝炎的诊断和治疗提供参考。     

纳洛酮对脑出血大鼠抓握能力的改善及血清S100B水平的影响

目的：探讨纳洛酮对脑出血大鼠抓握能力的改善及血清S100B水平的影响，为其临床应用提供理论依据。方法：40只SD大鼠随机分成假手术组，手术组，纳洛酮组，脑复康组，参照Rosenberg法制作大鼠脑出血模型，造模第二天测定大鼠抓握能力，用ELISA法检测造模后24小时及48小时血清S100B水平。结果：（1）纳洛酮组大鼠抓握能力明显好于手术组，两者比较有显著差异（P<0.05）。（2）纳洛酮组大鼠血清S100B水平明显低于手术组, 两者比较有显著差异（P<0.05）。结论：纳洛酮能明显改善脑出血大鼠抓握能力，降低血清S100B水平，具有神经保护作用。     

五常法在手术室腹腔镜管理中的应用

目的:探讨确保腹腔镜手术的顺利进行,提高手术质量,延长设备、器械使用寿命的方法。方法:总结我院自1993年3月开展腹腔镜手术以来,五常法在手术室腹腔镜管理中的应用情况。结果:无一例因腹腔镜器械故障或欠缺而影响手术的顺利进行。结论:五常法的应用减少了手术护理工作中的缺陷,增强了手术室护士工作的主动性和计划性,增强了手术护士的工作成就感。     

Development of mitochondrial SSU rDNA-based oligonucleotide probes for specific detection of common airborne fungi

In this study we sequenced partial mitochondrial small subunit rDNA from 32 fungal strains representing 31 species from 16 genera. Most of these species are common airborne fungi and pathogens that may cause various public health concerns. Sequence alignment showed several conserved and highly variable regions. The variable regions were deployed to design oligonucleotide probes for each fungal species. The specificity of the designed probes was first examined through homology search against GenBank database then further verified through hybridization experiments to 38 fungal strains. A total of 23 probes were verified as specific to 15 fungal species commonly detected in living and working environments. These new probes will have potential applications in clinical diagnosis and public health-related environmental monitoring.