常见致龋菌代谢组学鉴定的初步研究

目的初步将基于核磁共振的代谢组学方法应用于口腔致龋菌的鉴定,期望寻找一种能快速鉴定口腔致龋菌的方法。方法在改良TPY培养基中接种变形链球菌及粘性放线菌,用比浊法绘制生长曲线,选择两种细菌生长后4个时期的培养液检测核磁共振波谱,用主成分分析法进行数据分析。结果主成分分析显示两组数据内部有集中的聚类关系,可以区分两种细菌。结论代谢组学技术有望应用于口腔细菌的快速鉴定。     

耐药和非耐药口腔鳞癌Tca8113代谢组学方法鉴定的初步研究

目的:初步将基于氢谱核磁共振(1H-NMR)的代谢组学方法应用于口腔耐药和非耐药口腔鳞癌Tca8113的鉴定。方法:MTT法绘制细胞生长曲线并检测药物敏感性,免疫组织化学检测与多药耐药现象相关蛋白P-gp的表达情况;收集胞外代谢产物进行核磁共振检测,用主成分分析法进行数据分析。结果:主成分分析法显示耐药细胞和非耐药细胞数据内部有集中的聚类关系,基于氢谱核磁共振的代谢组学方法可以区分耐药和非耐药的Tca8113。结论:代谢组学方法在产生耐药性的口腔癌细胞的快速鉴定中具有良好的应用前景,有望成为一种新的检测手段。     

口腔常见链球菌代谢组学鉴定的研究

目的通过比较血链球菌和远缘链球菌的代谢物图谱,初步将基于核磁共振的代谢组学方法应用于口腔常见链球菌的快速鉴定。方法在液体TPY培养基中分别接种相同密度的血链球菌和远缘链球菌菌悬液,用比浊法测定菌悬液密度,绘制生长曲线。取2种细菌生长稳定期的培养液检测核磁共振图谱,进行主成分分析。结果主成分分析表明2种细菌的数据内部具有集中的聚类关系,该方法可以区分这2种细菌。结论代谢组学方法在口腔链球菌的快速鉴定中具有良好的应用前景。     

牙周可疑致病菌代谢组学鉴定的初步研究

目的分析比较牙周可疑致病菌的核磁共振代谢图谱,探讨用代谢组学方法快速鉴定口腔细菌的可能性。方法分别在BHI液体培养基中接种相同密度的牙龈卟啉单胞菌、中间普氏菌和具核梭杆菌,采用比浊法绘制生长曲线。取3种细菌生长稳定期的培养液进行核磁共振氢谱（1H-NMR）测定,用主成分分析法进行数据分析。结果主成分分析显示3组数据各自有较为集中的类聚关系,可以区分这3种细菌。结论代谢组学是一种具有良好应用前景的口腔细菌分类鉴定方法。     

变异链球菌、血链球菌及嗜酸乳杆菌代谢组学鉴定的初步研究

目的了解变异链球菌、血链球菌和嗜酸乳杆菌的代谢谱图,探讨基于核磁共振的代谢组学方法在口腔致龋菌快速鉴定中的应用。方法分别在改良TPY液体培养基中接种相同密度的变异链球菌、血链球菌及嗜酸乳杆菌菌悬液,采用比浊法计算细菌数,绘制生长曲线。选择这3种细菌生长稳定期的培养液检测核磁共振波谱,用主成分分析法进行数据分析。结果主成分分析显示3组数据内部有集中的聚类关系,可以区分这3种细菌。结论代谢组学分析是一种有良好发展前景的口腔细菌的快速鉴定方法。     

与口腔黏膜病相关的假丝酵母菌代谢组学鉴定的初步研究

目的 分析3种假丝酵母菌的磁共振代谢物图谱,探讨用代谢组学方法快速鉴定口腔黏膜致病菌的可行性。方法 在沙保培养基中分别接种白色假丝酵母菌ATCC 10231、热带假丝酵母菌ATCC 13803和光滑假丝酵母菌ATCC 15126,绘制生长曲线,选择3种菌生长稳定期的培养液检测其磁共振图谱,用主成分分析法进行数据分析。结果 主成分分析法显示：每两种细菌在主成分得分图中有组间分散、组内聚集的特点,可以区分不同的假丝酵母菌。结论 代谢组学分析技术是一种有良好发展前景的口腔细菌快速鉴定技术。     

儿童口腔放线菌与儿童龋的关系初探

目的检测儿童牙面龈上菌斑中的放线菌,初步探讨口腔放线菌与儿童龋病发生的关系。方法选择40例3~5岁儿童为研究对象,其中无龋组和龋敏感组各20例。用无菌牙签收集乳牙表面3个不同部位的龈上菌斑。龋敏感组收集完整面、白垩斑和龋洞内（ 牙本质层）的菌斑;无龋组收集唇面、邻面和!面沟裂的菌斑。提取菌斑的细菌DNA,用放线菌特异性引物进行聚合酶链反应,对其电泳条带进行记录分析。结果无龋组放线菌检出率为100%,龋敏感组为95%,二者间无统计学差异（ P>0.05）。内氏放线菌、戈氏放线菌、龋齿放线菌、衣氏放线菌和黏性放线菌在两组儿童的菌斑中均有检出,前3种放线菌在无龋组的检出率高于龋敏感组,二者间有统计学差异（ P<0.05）。2组儿童3个检测部位间的检出率无统计学差异（ P>0.05）。结论放线菌是儿童乳牙龈上菌斑中的主要定植细菌,可能是有益菌;其检出情况与乳牙检测部位的关系不大。     

口腔放线菌对白假丝酵母菌拮抗作用的体外实验研究

目的观测3种口腔放线菌对白假丝酵母菌的生长有无抑制作用。方法采用直接点种法观察抑菌圈,分别采用反点种菌落计数法和液体共培养法,观察在口腔放线菌作用下白假丝酵母菌菌落数量的变化。结果1）各实验组均未观察到清晰的抑菌圈;2）在黏性放线菌软琼脂上的白假丝酵母菌菌落数较对照组明显减少（P<0.05）;在溶牙放线菌和内氏放线菌软琼脂上无明显白假丝酵母菌生长,与对照组相比差异有统计学意义（P<0.01）;黏性放线菌组与溶牙放线菌组、内氏放线菌组相比,白假丝酵母菌生长差异有统计学意义（P<0.01）;3）分别与3种放线菌共培养的白假丝酵母菌菌落数量减少,与对照组相比差异有统计学意义（P<0.05）;3个实验组间差异无统计学意义（P＞0.05）。结论口腔黏性放线菌、溶牙放线菌和内氏放线菌对白假丝酵母菌的体外生长有抑制作用。     

一氢核磁共振的血浆代谢组学分析维生素B12对地塞米松诱导腭裂小鼠的阻抑作用

目的采用基于一氢核磁共振（1H-NMR）的代谢组学方法研究使用维生素B12后,阻抑本已诱发的唇腭裂发育早期过程的变化,并评估其可行性。方法选取对照组和实验组各12只怀孕17.5 d的C57BL/6J雌鼠,分别是仅注射维生素B12的孕鼠和注射维生素B12后再注射过量地塞米松引起腭裂的孕鼠,处理动物的血浆样本,并且观察B12对腭裂产生率的的影响。利用核磁共振技术检测血浆内源性小分子代谢产物,通过主成分分析方法（PCA）确定代谢物成分的变化。结果根据2组腭裂是否发生,PCA得分散点图产生了显著的差别。结论核磁共振的代谢组学方法是一种可行和有效的方法,可以深入探索唇腭裂的发病机制,并且为以后研究维生素B12的代谢机制奠定了基础。     

链球菌和放线菌的胞外代谢物代谢组学鉴定

目的 检测不同口腔细菌的细胞外代谢产物,发掘各种细菌的特征性代谢谱图,探讨代谢组学在口腔细菌鉴定中的作用。方法取3组细菌生长对数后期培养液,行磁共振氢谱仪检测和主成分分析(PCA)及最小偏二乘法判别分析(PLS-DA),鉴别各个细菌间的代谢产物。结果3组细菌的代谢产物明显不同,各自聚集、分布区域明显分开;PLS-DA区...     

内氏放线菌细胞壁成分诱导人成纤维细胞产生白细胞介素-1β、-6和肿瘤坏死因子α的研究

目的探讨内氏放线菌菌株ATCC19246细胞壁成分能否诱导人成纤维细胞产生白细胞介素-1β（IL-1β）、白细胞介素-6（IL-6）、肿瘤坏死因子α（TNFα）。方法采用提取脂磷壁酸（LTA）的方法提取内氏放线菌菌株ATCC19246细胞壁成分，用3种质量浓度（分别为1、10、100 mg/mL）提取物分别刺激人成纤维细胞THP-1细胞株，用ELISA方法测定细胞培养上清中的IL-1β、IL-6、TNFα。结果THP-1细胞株可以产生一定量的IL-1β、IL-6、TNFα，以质量浓度为10 mg/mL时诱导产生的量最高。结论内氏放线菌细胞壁提取物可以诱导THP-1细胞株产生IL-1β、IL-6、TNFα，但随着质量浓度变化产生的量存在差异。     

Comparison of polyclonal and monoclonal antibodies to Actinomyces and Arachnia species

Abstract – Polyclonal (PoAbs) and monoclonal (MoAbs) antibodies were produced to Actinomyces israelii serotypes 1 and 2, to Actinomyces naeslundii, and to Arachnia propionica, and their specificities were studied by an enzyme immunoassay (EIA). All PoAbs except those to A. propionica reacted also with at least one other Actinomyces species. Only the MoAb to A. naeslundii proved to be more specific than the corresponding PoAbs. This MoAb did not cross-react with other Actinomyces or Arachnia species, nor with any other anaerobic or aerobic bacteria studied by inhibition EIA. Immunoblotting studies indicated that the antibody specific to A. naeslundii is directed against a large molecular weight antigen (>150 kd), probably polysaccharide in nature. The produced PoAbs and MoAbs can be used for further analyses of the antigenic determinants of different Actinomyces and Arachnia species.     

Comparison of polyclonal and monoclonal antibodies to Actinomyces and Arachnia species

Polyclonal (PoAbs) and monoclonal (MoAbs) antibodies were produced to Actinomyces israelii serotypes 1 and 2, to Actinomyces naeslundii, and to Arachnia propionica, and their specificities were studied by an enzyme immunoassay (EIA). All PoAbs except those to A. propionica reacted also with at least one other Actinomyces species. Only the MoAb to A. naeslundii proved to be more specific than the corresponding PoAbs. This MoAb did not crossreact with other Actinomyces or Arachnia species, nor with any other anaerobic or aerobic bacteria studied by inhibition EIA. Immunoblotting studies indicated that the antibody specific to A. naeslundii is directed against a large molecular weight antigen (greater than 150 kd), probably polysaccharide in nature. The produced PoAbs and MoAbs can be used for further analyses of the antigenic determinants of different Actinomyces and Arachnia species.     

Actinomyces spp. in supragingival plaque of ethnic Chinese preschool children with and without active dental caries

Very limited molecular epidemiological data are available on the role of Actinomyces spp. in the pathogenesis of caries in the primary dentition. Therefore, we investigated their distribution in supragingival plaque of ethnic Chinese preschool children from Singapore and Hong Kong, either with or without active caries. Plaque samples were taken from intact interproximal enamel areas using dental floss. Bacterial genomic DNA of each sample was extracted and variable regions of 16S ribosomal DNA amplified and labelled with digoxigenin. Oligonucleotide probes specific for Actinomyces bovis, Actinomyces gerencseriae, Actinomyces israelii, Actinomyces meyeri, Actinomyces odontolyticus, catalase-negative Actinomyces naeslundii (genospecies 1 and 2) and catalase-positive Actinomyces naeslundii genospecies 2 (previously Actinomyces viscosus serotype II) were used to detect these species using Southern hybridization with a Minislot and Miniblotter system. A. odontolyticus, A. gerencseriae and A. meyeri were detected with similar frequency in both Singapore and Hong Kong samples or in those with and without active caries. However, the prevalence of A. naeslundii was significantly different in the two locales (p<0.05). A. odontolyticus (88.7%), A. gerencseriae (56.6%) and A. naeslundii (50.9%) were detected in a majority of the samples and the positive hybridization signals of A. gerencseriae in the caries-active group were stronger than from the caries-free group. A. bovis and A. israelii were undetectable in any of the samples. These data imply that A. odontolyticus, A. naeslundii and A. gerencseriae may play an important role in supragingival plaque formation on primary teeth in ethnic Chinese, with others such as A. meyeri contributing.