Fouad Ashraf F, Zerella Joseph, Barry Jody, Spångberg Larz S
Department of Endodontology, University of Connecticut Health Center, Farmington, Connecticut, USA.
Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2005 Jan;99(1):112-8. doi: 10.1016/j.tripleo.2004.06.064.
The objectives were to identify Enterococcus spp in nonhealing endodontic cases using PCR amplification and molecular sequencing, and to determine if the prevalence of enterococci is increased in diabetic patients.
Specimens from 40 cases undergoing retreatment were incubated in prereduced thioglycollate broth at 37 degrees C. Extracted DNA had PCR amplification using primers that target the tuf gene of 14 Enterococcus spp. PCR products were directly sequenced and identified phylogenetically.
Three cases were eliminated because the patients were on antibiotics or the tooth did not have a periradicular radiolucency. The remaining 37 specimens included 6 from diabetic patients. Eight specimens were positive for Enterococcus spp. Of these, 6 (19%) were from nondiabetic and 2 (33%) from diabetic patients (odds ratio = 2.1; chi squared, P = .45). Phylogenetically, all sequences from positive specimens matched E faecalis V583 (AE016947). Conclusion E faecalis was the only enterococcal species detected, with an overall prevalence of 22%.
本研究旨在通过聚合酶链反应（PCR）扩增和分子测序，在未愈合的牙髓病病例中鉴定肠球菌属，并确定糖尿病患者中肠球菌的患病率是否增加。
从40例接受再治疗的病例中采集标本，在37℃的预还原硫乙醇酸盐肉汤中培养。提取的DNA使用针对14种肠球菌属tuf基因的引物进行PCR扩增。PCR产物直接测序并进行系统发育鉴定。
3例病例被排除，原因是患者正在使用抗生素或牙齿没有根尖周透射区。其余37份标本中，6份来自糖尿病患者。8份标本的肠球菌属检测呈阳性。其中，6份（19%）来自非糖尿病患者，2份（33%）来自糖尿病患者（优势比=2.1；卡方检验，P=0.45）。在系统发育上，阳性标本的所有序列均与粪肠球菌V583（AE016947）匹配。结论粪肠球菌是唯一检测到的肠球菌属，总体患病率为22%。
