口腔黏膜上皮癌变过程中内皮素Ⅰ表达的定量研究

目的 了解正常口腔黏膜,癌前病变及癌组织中内皮素I(ET-I)表达特点及其变化规律。方法采用免疫组化和图象分析技术,对人正常口腔黏膜(NOR)10例、口腔黏膜下纤维化(OSF)10例、鳞状细胞癌(SCC)15例上皮细胞的ET-I含量进行图像分析。结果 ①ET-I在OSF、OLK、SCC组织中的表达增强,阳性物质主要位于上皮棘细胞、基质细胞的胞浆胞膜上,且ET-I含量显著高于正常对照组(p<0.01)。②OLK、SCC上皮细胞ET-I含量呈显著增加趋势(p<0.05)。③OSF上皮细胞ET-I含量显著高于OLK(p<0.05),与SCC相比无显著性差异(p>0.05)。结论 ET-I含量在口腔癌前病变至癌变过程中可能存在一种量变关系,OSF中ET-I过量表达可能提示其上皮细胞的癌变潜能。     

基质金属蛋白酶-7和c-myc在口腔鳞状细胞癌中的表达和意义

目的研究基质金属蛋白酶-7(MMP-7)与c-myc在口腔鳞状细胞癌组织中的表达及其意义。方法应用免疫组化EliVisionTM法分别检测MMP-7和c-myc在49例口腔鳞状细胞癌和5例正常口腔黏膜上皮中的表达情况。结果1)MMP-7和c-myc在口腔鳞状细胞癌组织中的阳性表达率分别为83.7%和77.6%。2)在不同病理分级、不同临床分期和有无淋巴转移的口腔鳞状细胞癌组织中MMP-7阳性表达率的差异有统计学意义(P<0.05)。3)在不同病理分级和有无淋巴转移的口腔鳞状细胞癌组织中c-myc阳性表达率的差异亦有统计学意义(P<0.05)。4)口腔鳞状细胞癌组织中MMP-7和c-myc的表达呈正相关(P<0.05)。结论MMP-7和c-myc在口腔鳞状细胞癌组织中均有高表达,在口腔鳞状细胞癌的发病过程中,其高表达具有协同效应,共同促进口腔鳞状细胞癌的发生和发展。     

IL-6在犬乳恒牙替换过程中的表达和意义

目的：研究犬乳恒牙替换过程中IL-6在组织中的表达情况，分析IL-6在乳恒牙替换过程中可能发挥的作用。方法：应用免疫组织化学及半定量分析的方法检测IL-6在成年犬和幼犬替牙期的表达。结果：成年犬IL-6的表达呈阴性；幼犬替牙期的乳牙成牙本质细胞层、牙周膜和恒牙胚上方骨组织中均有阳性信号表达。结论：提示IL-6可能在幼犬乳牙替换过程中发挥着一定的作用。     

Langerhans cells express matrix metalloproteinases 9 and 2 and tissue inhibitors of metalloproteinases 1 and 2 in healthy human gingival tissue and in periodontitis

BACKGROUND: As antigen-presenting cells, Langerhans cells may play an important role in the initiation and maintenance of periodontal disease. This study is the first report that extends our knowledge of the expression of matrix metalloproteinases and their endogenous tissue inhibitors by Langerhans cells in healthy and diseased gingival tissues. METHODS: Single and double immunolabeling procedures were carried out using monoclonal antibodies against CD1a, matrix metalloproteinases 2 and 9, and tissue inhibitors of matrix metalloproteinases 1 and 2, and analyzed by conventional and confocal microscopes. RESULTS: Langerhans cells expressed matrix metalloproteinases 2 and 9, and tissue inhibitors of matrix metalloproteinases 1 and 2 in healthy and diseased gingival tissues. The tissue inhibitors of matrix metalloproteinase-positive Langerhans cells were mainly observed in the upper epithelial layers. Matrix metalloproteinase 9-positive Langerhans cells were observed especially during periodontitis and in the basal epithelial layer or crossing the basement membrane. CONCLUSION: During periodontal disease, changes in the expression of matrix metalloproteinases and their tissue inhibitors by gingival Langerhans cells could be implicated in the migration of the cells towards the connective tissue.     

人牙髓组织缺氧耐受机制的初步研究

目的：研究缺氧诱导因子-1α（Hypoxia inducible factor-1α，HIF-1α）和环氧化酶-2（Cyclooxygenase-2，COX-2）在人正常牙髓和炎症牙髓中的免疫定位，探讨缺氧耐受机制在牙髓炎病程中和牙髓自身修复过程中的作用和意义。方法：通过SP法对第1组10例健康牙髓、第2组10例深龋（有过敏症状但无牙髓炎症状）患牙牙髓、第3组15例急性牙髓炎牙髓和第4组15例慢性牙髓炎牙髓进行免疫组化染色，分别对HIF-1α和COX-2进行免疫定位和半定量分析。结果：①HlF-1α在第1组健康牙髓和第2组深龋牙髓标本中，只有个别标本呈弱阳性表达，二组问无显著性差异（P〉0．05），但对比其它二组标本则有显著性差异（P〈0．001）：第3组急性牙髓炎牙髓呈强阳性表达，第四组慢性牙髓炎牙髓亦呈阳性染色与第3组比较总体偏弱，有显著性差异（P〈0．05）。②COX-2在第1组牙髓中个别标本呈弱阳性表达；第2组标本绝大多数染色呈弱阳性，与第1组比较有显著性差异（P〈0.05）；第3组标本染色均呈强阳性，与前两组比较有显著差异性伊值分别为P〈0.001，P〈0．05）；第4组标本亦呈阳性染色，总体上阳性程度明显高于第l组（P〈0．001），高于第2组（P〈0．05），弱于第3组（P〈0．05）。HIF-1α与COX-2的表达关系主要在第3组和第4组牙髓标本中体现明显，在第3组二者的变化大致呈平行关系；在第4组基本呈反向变化关系。结论：HIF-1α和COX-2在牙髓炎病程中可能发挥着重要的生理和病理作用，在牙髓炎进程中和牙髓自身修复过程中可能存在着缺氧环境和缺氧耐受机制。     

正畸牙移动过程中CBFa1/Osf2和BMPs在牙周组织中的表达

目的：通过比较CBFa1／Osf2和BMPs在牙周组织中的表达及变化，探讨在正畸骨改建过程中，这两个对骨形成起到重要作用的因子之间的相互关系，为进一步深入研究正畸牙移动的生物学机制奠定基础。方法：建立大鼠正畸牙移动的动物模型，并采用免疫组织化学的方法检测CBFa1／Osf2和BMPs在此过程中的表达。结果：正畸牙移动过程中CBFa1／Osf2和BMPs在牙周组织的分布及表达变化的时间上具有明显的一致性；均表现为实验组表达明显强于对照组，张力侧表达强于压力侧；其中成骨细胞、成纤维细胞及破骨细胞均为强表达。结论：CBFa1／Osf2和BMPs均参与了正畸的骨改建过程，且可能在正畸骨改建中起到重要作用。     

Immunohistochemical detection of uPA, uPAR, PAI-1, and maspin in ameloblastic tumors

BACKGROUND: To evaluate the roles of extracellular matrix (ECM)-degrading serine proteinase in progression of odontogenic tumors, expression of urokinase-type plasminogen activator (uPA), uPA receptor (uPAR), plasminogen activator inhibitor-1 (PAI-1), and maspin was analyzed in ameloblastic tumors as well as in tooth germs. METHODS: Tissue specimens of 10 tooth germs, 45 ameloblastomas, and 5 malignant ameloblastic tumors were examined immunohistochemically with the use of antibodies against uPA, uPAR, PAI-1, and maspin. RESULTS: Immunohistochemical reactivity for uPA, uPAR, PAI-1, and maspin was detected in normal and neoplastic odontogenic tissues: uPA was recognized predominantly in mesenchymal cells, uPAR was evident in epithelial cells, PAI-1 was found in both epithelial and mesenchymal cells, and maspin was expressed only in epithelial cells. The levels of uPA and uPAR immunoreactivity in ameloblastic tumors were slightly higher than the levels in tooth germs, while PAI-1 reactivity in ameloblastomas tended to be lower than that in tooth germs. The level of maspin immunoreactivity in ameloblastomas was significantly higher than that in tooth germs, and ameloblastic carcinoma showed decreased maspin reactivity. CONCLUSION: Expression of uPA, uPAR, PAI-1, and maspin in tooth germs and ameloblastic tumors suggests that interactions among these molecules contribute to ECM degradation and cell migration during tooth development and tumor progression. Altered expression of the serine proteinase and its associated molecules in ameloblastic tumors may be involved in oncogenesis of odontogenic epithelium.     

Expression of endothelial adhesion molecules in the alveolar ridge mucosa,gingiva and periimplant mucosa

OBJECTIVES: The purpose of this study was to analyze the expression of adhesion molecules on endothelial cells in the alveolar ridge mucosa, the gingiva and the periimplant mucosa in humans. MATERIAL AND METHODS: Twelve partially edentulous subjects were included in the study. In each subject, one soft tissue biopsy was harvested from the edentulous alveolar ridge mucosa, one from a tooth site and one from an implant site. After 3 weeks of undisturbed plaque accumulation, an additional biopsy was obtained from one tooth and one implant site in each subject. The tissue samples were snap frozen and prepared for immunohistochemical analysis. RESULTS: In the alveolar ridge mucosa, smaller proportions of endothelial cells expressing ICAM-1, ELAM-1 and VCAM-1 were observed than in the gingiva. ELAM-1-positive cells occurred in lower numbers than in periimplant mucosa. After 21 days of plaque accumulation, ELAM-1 was increased in tooth sites, but decreased in periimplant mucosa. CONCLUSION: The results of the present study indicated that the proportions of activated endothelial cells and the extravasation of leukocytes is larger in gingiva and periimplant mucosa than in alveolar ridge mucosa. This might be due to the less permeable keratinized epithelial layer in the edentulous ridge mucosa, which offers proper protection against microbial pathogens. The greater expression of endothelial cell adhesion molecules during experimental gingivitis, compared to periimplant mucositis, may reflect its longer history of repeated antigenic assaults.     

釉原蛋白在人牙胚发育不同时期表达的免疫组化研究

目的：探讨釉原蛋白在人牙胚发育不同时期的表达及其意义。方法：采用免疫组织化学方法观察釉原蛋白在不同发育阶段人牙胚中的分布。结果：在前成釉细胞、基底膜及前成牙本质细胞相邻部位都呈阳性反应。牙乳头细胞及牙本质呈阴性反应。釉原蛋白分布于釉质全层，在釉质浅层及与成釉细胞界面处呈线状强阳性染色，在后期矿化成熟时，成釉细胞及釉质染色阴性。结论：釉原蛋白与成釉细胞、成牙本质细胞的分化及釉质的矿化有关。     

Effect of capsaicin treatment or inferior alveolar nerve resection on dentine formation and calcitonin gene-related peptide- and substance P-immunoreactive nerve fibres in rat molar pulp

The aim of this study was to investigate whether decreased sensory innervation induced by capsaicin treatment or axotomy of the inferior alveolar nerve has an effect upon dentine formation in the rat first molar. Dentine formation was visualized by intravital injection of Procion brilliant Red H8BS and denervation was verified immunohistochemically for the neuropeptides calcitonin gene-related peptide (CGRP) and substance P. The observation times were 6 weeks for the capsaicin-treated group and 11 days for the axotomized group. Capsaicin injections caused a consistent reduction in numbers of CGRP- and substance P-immunoreactive fibres in the pulps and a somewhat smaller reduction in the periodontal tissues. Unilateral axotomy of the inferior alveolar nerve induced an almost complete loss of immunoreactive fibres in the pulp and in the mesial gingiva of the first molar. Dentine formation at the mesial pulp horn and at the central pulp floor was significantly reduced in both groups compared to controls. The results suggest that sensory neuropeptides such as CGRP and substance P may play a part in dentine formation.