Endpoint quantitative PCR assays for Bacteroides forsythus,Porphyromonas gingivalis,and Actinobacillus actinomycetemcomitans

BACKGROUND: Conventional polymerase chain reaction (PCR) assays for periodontal pathogens are so sensitive that they detect infections of no clinical significance. Quantitative PCR (qPCR) may provide a solution to this problem. However, most qPCR systems require expensive real-time thermal cyclers. OBJECTIVE: Our goal was to develop qPCR assays which would allow endpoint quantification. MATERIALS AND METHODS: 16S rRNA primers for Bacteroides forsythus, Porphyromonas gingivalis, and Actinobacillus actinomycetemcomitans were adapted to the Amplifluor qPCR system, which incorporates fluorescein into the PCR product so that endpoint fluorescence is proportional to the original amount of template. DNA dilutions representing known numbers of cells were used as standard curves. Pooled subgingival plaques from the four deepest pockets of 21 severe adult periodontitis patients were assayed. Buccal molar supragingival plaque from 35 dental students provided healthy controls. Endpoint fluorescence was measured with a microplate reader. RESULTS: Optimized standard curves were linear in log-log or semilog fits over a range of 100-10(6) cells. Countable B. forsythus was present in all patients, with counts (as logs) from 2.4 to 7.3 (mean = 5.0), and 11 controls with counts from 2.1 to 4.5 (mean = 3.0). P. gingivalis was present in 11 patients and no controls, with counts from 2.2 to 4.7 (mean = 3.2). A. actinomycetemcomitans was present in two patients, with counts of 1.5 and 3.5. CONCLUSIONS: Amplifluor qPCR assays discriminated between plaque samples differing by one log or more, allowing major infections to be distinguished from minor ones. This approach allows high-throughput qPCR of plaque samples, using equipment available to many laboratories.     

Streptococci dominate the diverse flora within buccal cells

Previously, we reported that intracellular Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Tannerella forsythensis were present within buccal epithelial cells from human subjects, as lesser components of a polymicrobial flora. In this study, we further characterized that intracellular flora by using the same double-labeling techniques to identify Fusobacterium nucleatum, Prevotella intermedia, oral Campylobacter species, Eikenella corrodens, Treponema denticola, Gemella haemolysans, Granulicatella adiacens, and total streptococci within buccal epithelial cells. All those species were found within buccal cells. In every case, species recognized by green-labeled species-specific probes were accompanied by other bacteria recognized only by a red-labeled universal probe. Streptococci appeared to be a major component of the polymicrobial intracellular flora, being present at a level from one to two logs greater than the next most common species (G. adiacens). This is similar to what is observed in oral biofilms, where diverse species interact in complex communities that often are dominated by streptococci.     

Cervical Castleman disease in children

We report a new case of cervical Castleman disease (hyaline vascular type) in a 6-year-old child. The mass was shown on computed tomography and magnetic resonance angiography (MRA) to be compressing the bifurcation of the right common carotid artery. At operation four masses were found, which were tightly adherent to both the artery and the right jugular vein. These were removed by blunt dissection and there were no signs of recurrence after 6 months. This is a rare tumour (we know of only 24 other reports), which is usually asymptomatic, and of uncertain prognosis.     

成人牙周炎治疗前后龈沟液蛋白质的电泳分析

目的通过分析成人牙周炎患者同一位点基础治疗前后１个月龈沟液（ｇｉｎｇｉｖａｌｃｒｅｖｉｃｕｌａｒｆｌｕｉｄ，ＧＣＦ）中蛋白成分的改变，以期发现能够反映牙周健康及疾病状况的特异蛋白。方法采用滤纸条法收集１２例成人牙周炎患者５６个位点ＧＣＦ样本，以十二烷基磺酸钠聚丙烯酰胺凝胶电泳（ＳＤＳＰＡＧＥ）法分离，ＩｍａｇｅＭａｓｔｅｒＴＭ电泳图象分析仪分析其中的蛋白质。结果治疗后蛋白区带数及非血清源低分子量１２０００，１００００蛋白的丰度及百分含量较治疗前显著减少（分别为Ｐ＜０００１和Ｐ＜００５），而３８０００蛋白百分含量呈增加趋势且与治疗前牙周探诊深度和ＧＣＦ量呈负相关（Ｐ＜００５）。结论分子量为１２０００，１００００的蛋白与牙周炎症有关；分子量３８０００的蛋白与疾病的好转有关     

全下颌种植固定义齿三维各向异性有限元模型的建立

种植义齿的远期成功率与其生物力学相容性关系密切。本文采用CT扫描数字探测法和图形图像处理分析系统，在微机上完成全下颌种植固定义齿三维空间坐标数据测量，在Var-6510计算机上采用ANSYS有限元分析程序的布尔运算和单元自动划分功能建立全下颌种植固定义齿的三维各向异性有限元模型；并在咀嚼肌附着区和颞颌关节区模拟口腔咀嚼状况时加约束反力，建立生理状况下的下颌有限元模型。     

Mandibular distraction osteogenesis reconstructed the upper airway in a case of Melnick�CNeedles syndrome

Introduction

We report a 16-year-old female with Melnick?CNeedles syndrome complicated with severe obstructive sleep apnea?Chypoxia syndrome.

Clinical report

An overnight sleep study demonstrated that the patient had severe obstructive sleep apnea with an apnea?Chypopnea index of 95/h. The lowest oxygen saturation was only 34%. The distraction osteogenesis technique was used to lengthen her mandible for the reconstruction of her upper airway.

Result and Discussion

Postoperative panorex showed that the bilateral body of her mandible had been distracted about 16?mm singulorumly in the end of our distraction. Lateral radiograph revealed that the diameter of oral pharynx widen nearly 5?mm. The patient recovered after the upper airway reconstruction.