PerioGlas/rhBMP-2用于兔下颌骨侧嵴扩增的初步实验评估

目的 探讨PerioGlas（bioaetive glass，BG）与重组人骨形成蛋白-2（recombinent human bone morphogenetic protein-2，rhBMP-2）在下颌骨侧嵴扩增的可行性。方法在免磨牙区唇侧骨皮质表面，球钻预备4～6个5mm的骨缺损，一侧骨皮质表面和骨缺损内放置BG／rhGBMP-2，另一侧作为空白对照。术后正常饮食，2、4、8周后大体观察、组织学检查和组织学测量。结果观测时间内所有植入体固住良好，没有炎性反应。下颌骨表面明显加厚。材料表面骨组织覆盖；组织学观察皮质骨表面和骨缺损内新骨形成，2周纤维组织分割BG颗粒，4周大量新生骨呈编织骨样结构，新骨与BG颗粒直接结合。8周部分BG颗粒已降解被新骨取代，并与植骨床骨皮质表面直接结合，极少量残留颗粒被新骨包围。rhBMP-2／BG的表面成骨作用比单一BG、rhBMP-2好，具有明显的骨诱导性和骨引导性。新骨形成百分比明显高于BG（P〈0．05）。临床操作性能佳，易于放置，有止血作用。结论rhBMP-2／13G可以用于下颌骨侧嵴扩增。     

牙种植体周围龈沟液中蛋白含量的研究

目的 :观察修复后1年内种植体周围龈沟液 (PISF)中蛋白含量的变化 ,初步探讨其变化与种植体周围组织炎症的关系。方法 :以基台连接术后1～1.5月为基线 ,在修复体完成后3、6、12个月时 ,对12名患者26颗Branemark种植体的52个位点进行临床及PISF蛋白含量检测。结果 :各时期粘膜炎组的PISF蛋白含量普遍高于健康组 ,且有随粘膜炎程度加重而升高的趋势 ,重度粘膜炎组的PISF蛋白含量明显高于健康组 (P<0.05)。骨丧失位点的PISF蛋白含量高于无骨丧失的位点。结论 :PISF蛋白含量可以在一定程度上反映种植体周围组织的炎症状况。     

Gene expression analysis in cells of the dentine-pulp complex in healthy and carious teeth

Knowledge of the molecular events that occur in carious disease has so far been constrained due to difficulties in obtaining sufficient quantities of the dental tissues and cells involved. Our histological findings indicate that a pulp-odontoblast cellular complex can be obtained from carious and healthy human teeth when exposed to low-temperatures prior to pulpal extirpation and from rodent teeth processed at room-temperature. In contrast, pulpal tissue extracted from room-temperature processed human teeth and low-temperature processed rodent teeth resulted in the odontoblast layer remaining attached to the pulp chamber. Semi-quantitative RT-PCR (sq-RT-PCR) analysis confirmed that markers previously shown to be preferentially expressed in odontoblasts, namely dentin sialophosphoprotein (DSPP) and Nestin, amplified more readily from the extracted pulp-odontoblast complex, as compared to pulpal tissue alone, in both human and rodent samples. Subsequent gene expression analysis of collagen-1alpha and collagen-3alpha indicated levels were significantly higher in carious pulpal tissue. In addition, analysis characterising the expression of members of the transforming growth factor and bone morphogenic protein families and their receptors indicated in general, that these genes were expressed by healthy odontoblasts and up-regulated in both pulpal cells and odontoblasts in response to carious injury. Use of this temperature-sensitive dental tissue preparation procedure allows detection of differential gene expression in odontoblasts and other pulpal cells in healthy and carious tissue.     

A IIIman protein is involved in the transport of glucose,mannose and fructose by oral streptococci

We show in this article that the transport of glucose, mannose and fructose by the phosphoenolpyruvate: mannose phosphotransferase system of oral streptococci requires the participation of a protein component that we have called III_man. This protein was purified from Streptococcus salivarius by chromatography on DEAE-cellulose, DEAE-TSK, hydroxyapatite, and Dyematrex Green A. The purified protein migrated as a 38,900 molecular weight protein on a sodium dodecyl sulfate polyacrylamide gel. However, electrophoretic analysis of phosphoproteins and Western blot experiments indicated the presence in membrane-free cellular extracts of S. salivarius of 2 different forms of III_man having molecular weights of 38,900 and 35,200. The presence of the high-molecular-weight form of III_man was observed by immunodiffusion. Western blot and phosphorylation by [³²]PEP in S. salivarius, Streptococcus mutans, Streptococcus sobrinus, and Streptococcus lactis but not in Streptococcus faecium, Staphylococcus aureus, Bacillus subtilis and Lactobacillus casei. Antibodies directed against the III_man of S. salivarius did not react with the III_man of Escherichia coli.     

变形链球菌表面蛋白和葡糖基转移酶基因疫苗免疫防龋动物实验:体质量影响研究

目的 :了解变形链球菌基因疫苗单独及联合免疫对定菌鼠体质量的影响。方法 :2 8d龄Wistar大鼠 3 6只 ,随机分为pcDNA3 pac组、pcDNA3 gtfB组、pcDNA3 pac联合pcDNA3 gtfB组、变形链球菌灭活全菌阳性对照组、pcDNA3空载体阴性对照组和PBS液空白对照组 ,进行 3次双侧颌下腺腺周注射免疫 ,建立定菌鼠模型及诱龋实验 3个月 ,于实验开始和结束时测定体质量。结果 :基因疫苗免疫组体质量与 pcD NA3及PBS组无显著差异 (P >0 .0 5) ,而灭活全菌细胞免疫组体质量显著下降 (P <0 .0 1)。结论 :pcD NA3 gtfB和pcDNA3 pac对大鼠体质量无不良影响 ,较灭活全菌疫苗安全     

Subcutaneous administration of lactone form of simvastatin stimulates ectopic osteoinduction by rhBMP-2

OBJECTIVE: To evaluate the effects of various 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (statins) on ectopic osteoinduction by recombinant human bone morphogenetic protein-2 (rhBMP-2) using different administration methods. MATERIALS AND METHODS: Disks containing 5 mug of rhBMP-2 and type I collagen were implanted into the calf muscles of 6-week-old male rats (n = 64). Either the lactone form of simvastatin (SV), open hydroxy-acid form of simvastatin (SVA), cerivastatin (CVA), or vehicle (control) was then administered per orally (PO group) or subcutaneously (SC group) for 20 days. The disks were removed on day 21 after implantation, and ectopic induced bone formation was evaluated by radiographic, histologic, and biochemical analysis. RESULTS: Both the projected and radiopaque area on X-ray film, and the calcium content of the SV group in the SC group (SV-SC group) were significantly greater than those in the other SC and PO groups. Alkaline phosphatase activity and tartrate-resistant acid phosphatase activity in the SV-SC group were significantly lower than those in the other SC and PO groups. Histologic examination revealed an increase of ectopic induced bone volume in the SV-SC group. CONCLUSION: Subcutaneous administration of SV stimulates ectopic osteoinduction by rhBMP-2 through reduction of bone turnover.     

OmpA-like protein influences cell shape and adhesive activity of Tannerella forsythia

Tannerella forsythia, a gram-negative fusiform rod, is implicated in several types of oral anaerobic infections. Most gram-negative bacteria have OmpA-like proteins that are homologous to the OmpA protein in Escherichia coli. We identified an OmpA-like protein in T. forsythia encoded by the tf1331 gene as one of the major proteins by mass spectrometric analysis. Two-dimensional, diagonal electrophoresis showed that the OmpA-like protein formed a dimeric or trimeric structure via intermolecular disulfide bonds. A biotin labeling experiment revealed that a portion of the protein was exposed on the cell surface, even though T. forsythia possesses an S-layer at the outermost cell surface. Using a tf1331-deletion mutant, we showed that the OmpA-like protein affected cell morphology. The length of the mutant cell was reduced almost by half. Cell swelling was observed in more than 40% of the mutant cells. Moreover, the mutant exhibited decreased adhesion to fibronectin, retarded autoaggregation, and reduced cell surface hydrophobicity. These results suggest that the OmpA-like protein in T. forsythia plays an important role in cellular integrity and adhesive function.     

热休克蛋白47重组质粒对糖尿病大鼠皮肤创口愈合影响的实验研究

目的：初步研究热休克蛋白47（HSP47）重组质粒pTraeer—CMV—HSP47局部注射对糖尿病大鼠皮肤创口愈合的影响，探讨以HSP47质粒为摹础的基因治疗促进糖尿病皮肤创口愈合的可行性和有效性．方法：制备四氧嘧啶诱导的糖尿病大鼠皮肤创口愈合模型，创缘皮下局部注射HSP47重组质粒，观察其对皮肤创口愈合的影响，并用免疫组织化学、荧光定量RT—PCR、Western blotting检测创口愈合过程中HSP47和collagen Ⅰ的表达变化。结果：在糖尿病大鼠皮肤刨缘连续两次注射质粒后第3、6、9天．免疫组织化学、荧光定量RT-PCR和Western blotting检测证实，HSP47重组质粒组比对照组能显著增加创口中的HSP47和collagenⅠ的表达。结论：在糖尿病大鼠皮肤创口周围注射质粒pTracer—CMV—HSP47，能明显增强HSP47和coilagenⅠ的表达，有助于改善创口愈合，HSP47可能是促进糖尿病皮肤创口愈合的潜在治疗靶点。     

涎腺腺样囊性癌中p16蛋白,增殖细胞核抗原(PCNA)染色与病理分型、神经侵犯和复发的关系

目的 :探讨涎腺腺样囊性癌中 p16蛋白与PCNA在染色与病理分型、神经侵犯、复发中的关系。 方法 :利用免疫组化SP法 ,对 5例正常涎腺组织和 3 6例涎腺腺样囊性癌组织p16蛋白及PCNA染色进行检测 ,并对患者进行 10年随访观察。结果 :3 6例腺样囊性癌中 ,不同病理分型癌细胞组织中 p16蛋白阳性染色率间差异有统计学意义 (P <0 .0 5 ) ,PCNA阳性染色率间差异无统计学意义 (P >0 .0 5 ) ,有无神经侵犯癌组织中 p16蛋白阳性染色率间差异无统计学意义 (P >0 .0 5 )。有无复发癌组织中p16蛋白阳性染色率间差异有统计学意义 (P <0 .0 5 )。PCNA阳性染色率间差异有统计学意义 (P <0 .0 5 )。结论 :p16基因突变、缺失与腺样囊性癌病理类型有关 ,其表达水平反映肿瘤组织分化程度。p16蛋白及PCNA表达水平可以作为临床评价肿瘤侵袭性和预测复发的指标