Tang G, Yip H K, Samaranayake L P, Luo G, Lo E C M, Teo C S
Oral Bio-Sciences, Faculty of Dentistry, The University of Hong Kong, Hong Kong, SAR, China.
Caries Res. 2003 Sep-Oct;37(5):381-90. doi: 10.1159/000072172.
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.
关于放线菌属在乳牙龋齿发病机制中的作用，现有的分子流行病学数据非常有限。因此，我们调查了来自新加坡和香港的有或无活动性龋齿的华裔学龄前儿童龈上菌斑中放线菌属的分布情况。使用牙线从完整的邻面釉质区域采集菌斑样本。提取每个样本的细菌基因组DNA，扩增16S核糖体DNA的可变区并用洋地黄毒苷标记。使用针对牛放线菌、杰氏放线菌、衣氏放线菌、迈氏放线菌、溶齿放线菌、过氧化氢酶阴性的内氏放线菌（基因型1和2）以及过氧化氢酶阳性的内氏放线菌基因型2（以前的粘性放线菌血清型II）的寡核苷酸探针，通过Minislot和Miniblotter系统进行Southern杂交来检测这些菌种。在新加坡和香港的样本中，或有和无活动性龋齿的样本中，溶齿放线菌、杰氏放线菌和迈氏放线菌的检出频率相似。然而，两个地区内氏放线菌的患病率有显著差异（p<0.05）。在大多数样本中检测到了溶齿放线菌（88.7%）、杰氏放线菌（56.6%）和内氏放线菌（50.9%），且龋齿活动组中杰氏放线菌的阳性杂交信号比无龋组更强。在任何样本中均未检测到牛放线菌和衣氏放线菌。这些数据表明，溶齿放线菌、内氏放线菌和杰氏放线菌可能在华裔儿童乳牙的龈上菌斑形成中起重要作用，迈氏放线菌等其他菌种也有一定作用。
