牙龈卟啉菌菌毛基因在转基因番茄果实中的特异表达及小鼠免疫实验

将编码牙龈卟啉菌菌毛蛋白（Fimbrillin,FimA）（第266-337Aa）与霍乱毒素B亚基（CTB）基因用农杆菌侵染法转入番茄植株,并利用番茄果实特异启动子E8使其在果实中实现特异表达,然后用特异表达的转基因番茄果实对实验小鼠进行口服免疫实验,研究转基因番茄果实的免疫原性。实验结果表明：获得的11株转化植株中,共有9株重组了CTB-FimA基因的植株在番茄果实中实现了特异表达;口服转基因番茄果实的免疫小鼠的血清中检测到抗FimA抗体;获得了以CTB为佐剂的在番茄果实中特异表达牙龈卟啉菌菌毛基因的植物口服疫苗候选植株。     

派丽奥软膏治疗固定义齿修复后再发牙周炎的疗效观察

目的观察派丽奥(米诺环素)软膏治疗固定义齿修复后再发牙周炎的疗效。方法选择自身配对固定义齿修复后再发慢性牙周炎患者48例共96颗牙,随机分成派丽奥组(n=48)和碘甘油组(n=48),观察8周后临床症状、牙周袋探诊深度(PD)、菌斑指数(PLI)、龈沟出血指数(SBI)改变。结果派丽奥组总有效率(76.4%)明显优于碘甘油组(45.1%)(P<0.01),PD、SBI、PLI值均比碘甘油组低(P<0.01)。结论派丽奥软膏治疗固定义齿修复后再发牙周炎有明显疗效。     

Quantification of tryptase and T-cell immunoglobulin mucin 1 double-positive mast cells in different degrees of human periodontitis

AIM：To examine the expression of T-cell immunoglobulin mucin 1 (TIM-1) on tryptase-positive mast cells (MCs) in different severities of human chronic periodontitis. METHODS：Human gingival specimens (n=92) were involved in this study, including healthy control (n=27), mild chronic periodontitis (n=34) and severe chronic periodontitis (n=31). The gingival specimens were fixed in 4% formaldehyde. Paraffin embedding and serial sectioning with hematoxylin and eosin staining were performed for histopathological examination, and double-immunofluorescence staining was conducted for identification of tryptase-TIM-1 double-positive MCs in the gingival tissues. RESULTS：Compared with the healthy controls, the densities (cells/mm2) of tryptase-TIM-1 double-positive MCs were significantly increased in both mild chronic periodontitis group (P<0.05) and severe chronic periodontitis group (P<0.01). However, compared with mild chronic periodontitis group, both the score of gingival tissue inflammation and the density of tryptase-TIM-1 double-positive MCs in the gingival tissues were significantly increased in severe periodontitis group (P<0.05). CONCLUSION：Significantly increased number of tryptase-TIM-1 double-positive MCs has the similar tendency as the severity of periodontitis inflammation in human chronic periodontitis, suggesting that tryptase-TIM-1 double-positive MCs may play an important role in human chronic periodotitis.     

福赛斯坦纳菌体外培养实验技术的研究

目的 探索福赛斯坦纳菌生长繁殖的基本条件,比较N-乙酰胞壁酸及不同营养因子对其生长繁殖的影响,筛选该菌体外培养的最佳营养条件,建立其体外培养的技术方法。方法 （1）培养基制备：在血平板中加0.005% N-乙酰胞壁酸形成改良培养基;制备血平板与不同浓度（0.5、3、10、50、100 mg/L）的N-乙酰胞壁酸形成的培养基;制备10 mg/L N-乙酰胞壁酸与氯化血红素、酵母提取物、维生素K₃、脱纤维羊血组合形成不同组别的培养基。（2）接种培养后,用磷酸盐缓冲液将细菌洗脱,并用酶标仪（OD₆₀₀）测定其吸光度。结果 福赛斯坦纳菌在含N-乙酰胞壁酸的培养基中生长更好,浓度为10 mg/L时促进作用最明显且细菌形态更为典型。在组3培养基中生长最快。结论 N-乙酰胞壁酸能促进福赛斯坦纳菌的生长繁殖,浓度为10 mg/L时促进作用最明显;N-乙酰胞壁酸及氯化血红素、维生素K₃、酵母提取物和脱纤维羊血组合能使其生长周期明显缩短。     

铁调素在慢性牙周炎性牙槽骨吸收中的作用

目的 探讨铁调素（Hepcidin）在慢性牙周炎性牙槽骨吸收过程中的作用,阐明铁离子及其相关调节蛋白在牙槽骨吸收中的重要生物学意义,以期为探索出有效地防治牙槽骨吸收的方法提供理论基础。方法 检测慢性牙周炎患者龈沟液（GCF）中铁离子、核因子KB受体活化因子配体（RANKL）、骨保护素（OPG）的表达水平,分析铁离子的含量与RANKL和OPG表达的相关性以及铁离子的含量与牙周炎性牙槽骨吸收的关系。结果 20例慢性牙周炎组受检牙GCF中铁离子、Hepcidin和RANKL的浓度高于健康对照组（P<0.05）,OPG的浓度低于健康对照组（P<0.01）。慢性牙周炎组GCF中RANKL和OPG的浓度与该受检牙4项临床指标：牙周探诊深度（PD）、附着丧失（AL）、菌斑指数（PLI）、龈沟出血指数（SBI）无相关（P>0.05）,铁离子浓度与Hepcidin浓度呈正相关（P<0.01）,与RANKL浓度呈正相关（P<0.05）,与OPG浓度无相关（P>0.05）。结论 慢性牙周炎导致的牙槽骨吸收与局部Hepcidin升高和发生铁过载有关。     

A modified method for inducing periodontitis in dogs using a silk-wire twisted ligature

This study was designed to assess the effectiveness of a modified silk ligature twisted with wire for inducing advanced periodontitis. Periodontitis was induced in five premolars and one molar of 20 healthy dogs over a 60-day period. The dogs were divided into four groups according to the ligature-inducing materials used: soft moistened food only, wire ligature (WL), silk ligature (SL) and twisted ligature with silk and wire (SWL). Periodontal indices were recorded, and dental radiographs were taken before and after 60 days of ligation. The ligatures were checked daily and the day the ligature fell out was noted. The period during which the ligatures were maintained was significantly shorter for the SL group compared to the SWL group (p < 0.05). Results of the clinical examination showed that almost all periodontal status parameters including the plaque index, gingival index, clinical attachment level, and bleeding on probing were significantly exacerbated in the SWL group compared to the other groups (p < 0.05). Radiographic evaluation demonstrated that alveolar bone levels were significantly lower in the SWL group than the other groups on day 60 (p < 0.05). These results suggested that experimental periodontitis induced by SWL could be an effective method for investigating periodontitis in canine models.     

Assessment of Alloxan-Induced Diabetic Rats as a Periodontal Disease Model Using a Selective Cyclooxygenase (COX)-2 Inhibitor

Several recent studies have reported that alloxan-treated rats with long-term hyperglycemia can develop naturally occurring periodontal disease (PD). Our previous studies detected dental caries in the same model. Therefore, these two lesions of different etiologies are expected to occur concurrently. In this study, we evaluated the use of diabetic rats as a PD model by employing a selective COX-2 inhibitor reported to be effective against PD. Six-week-old female F344 rats were divided into 3 groups: intact rats (control), alloxan-induced diabetic rats fed a standard diet (AL) and alloxan-induced diabetic rats fed a diet containing 0.01% etodolac (AL+Et). The animals were euthanized at 26 weeks of age, and their oral tissues were examined histopathologically. Gingivitis, marginal periodontitis and alveolar bone resorption were markedly enhanced along with dental caries in the AL group compared with the control group. However, the COX-2 inhibitor had no effect on periodontal inflammation in the AL+Et group. In addition, in the AL group, periodontitis was notably nonexistent around the normal molars, and gingivitis was scarcely worse than that in the control group. In the diabetic rats, the progression of periodontal inflammation was closely correlated with the severity of adjacent dental caries, and marginal periodontitis was frequently continuous with apical periodontitis. In conclusion, an alloxan-induced diabetic rat is not a model of PD but of dental caries. It is probable that in this model, hyperglycemia may enable crown caries to progress to apical periodontitis, while the associated inflammation may rostrally expand to surrounding periodontal tissue.