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91.
BACKGROUND AND OBJECTIVE: Bone morphogenic proteins are known, in animal models, to promote many developmental processes, including osteogenesis. Clinical trials are currently underway to evaluate the potential of bone morphogenic proteins to promote bone and periodontal regeneration in humans. The aim of this study was to establish an optimal cell culture condition for using to study the biological effects of recombinant human bone morphogenic protein-2 on periodontal ligament cells. MATERIAL AND METHODS: The roles of serum concentration, types of culture medium (alpha-modified essential medium or Dulbecco's modified Eagle's medium), the presence of osteoinductive medium (including dexamethasone, ascorbic acid and beta-glycerophosphate), and timing of addition of the osteoinductive medium and recombinant human bone morphogenic protein-2, on the expression of alkaline phosphatase were investigated in cultured periodontal ligament cells. Cytochemical stainings and biological assay of alkaline phosphatase were also demonstrated. RESULTS: Our results suggested that an increased concentration of serum might mask the effect of recombinant human bone morphogenic protein-2 on the expression of alkaline phosphatase in periodontal ligament cells. alpha-Modified essential medium was found to induce a stronger cytochemical staining of the alkaline phosphatase than Dulbecco's modified Eagle's medium under similar culture conditions. Pre-incubation of cells with osteoinductive medium before the addition of various concentrations of recombinant human bone morphogenic protein-2 enhanced greater alkaline phosphatase expression than the simultaneous presence of both osteoinductive medium and recombinant human bone morphogenic protein-2. CONCLUSION: The findings of this study suggest that the effect of recombinant human bone morphogenic protein-2 on periodontal ligament cells could be efficiently investigated after the proper selection of culture variables and temporal sequence of adding bioactive factors. The optimal culture condition identified in this study might be useful in further studies to elucidate the regulatory mechanism of periodontal ligament cells in periodontal regeneration after stimulation with recombinant human bone morphogenic protein-2. 相似文献
92.
1354 freshmen have been investigated to discover the relationship between dental diseases and environments,living habits and personal sanitary conditions,because urban young men like sweet foods and snacks,the incidence of caries is greater in the cities than in the country,more people with tetracycline discolored tooth live in urban areas than in the rustic ones,which is due to dense living conditions, vulnerable to respiratory organs disease,medical conditions and convenience of taking tetracycline when ill;on the other hand,gingivitis is more common within the country students than within the city students,for those students from the country are used to brush their tooth after adolescence and usually have more dental calculus which is harmful to the gingiva.More than half of the investigated freshmen are ignorant of correct method of brushing and oral health and that is important factors of high rate of dental disease,according to the above reasons,the effective measures should educated to prevent dental disease. 相似文献
93.
目的 探讨雷帕霉素(rapamycin)与顺铂(cisplatin)联合使用对趋化因子CCL19调节头颈鳞状细胞癌细胞活性的影响.方法 应用甲基噻唑基四唑(MTT)法及流式细胞仪检测顺铂及雷帕霉素对CCL19诱导后人头颈鳞状细胞癌淋巴结转移细胞系(PCI-4B、PCI-37B)生长抑制作用、细胞凋亡作用和细胞周期变化.使用Calcusyn软件计算两种药物(浓度比为80:1)联合使用时的剂量效应参数及联合指数(combination index,CI),使用SPSS 11.0软件包进行统计分析.结果 顺铂及雷帕霉素可以分别提高CCL19作用后细胞的生长抑制率(CCL19+顺铂作用后两细胞系的生长抑制率为21.22%±2.68%和22.76%±2.79%,CCL19+雷帕霉素作用后为19.46%±2.54%和20.6%±4.38%)、细胞G1期比例(CCL19+顺铂作用后两细胞系的G1期比例为72.14%±2.66%和76.39%±1.45%,CCL19+雷帕霉素作用后为75.26%±5.92%和74.00%±1.51%)和凋亡率(CCL19+顺铂作用后两细胞系的凋亡率9.59%±0.86%和7.55%±0.66%,CCL19+雷帕霉素作用后为8.21±1.80%和6.26±0.78%).两种药物浓度比为80:1联合使用时,PCI-4B细胞在半数抑制量(inhibitory concentration 50%,IC50)以下,CI<1,IC75以上CI>1;PCI-37B则在IC75以下CI<1,IC90以上CI>1.结论 顺铂及雷帕霉素均有抑制CCL19对人头颈鳞状细胞癌淋巴结转移细胞的活性调节作用,并且二者联合使用存在协同作用.Abstract: Objective To investigate the synergistic effects of rapamycin and cisplatin on head and neck squamous cancer cells regulated by chemokine( C-C motif) ligand 19 (CCL19). Methods The role of rapamycin and cisplatin was detected on cell-cycle and apoptosis in CCL19 induced PCI-4B and PCI-37B cells by methyl thiazolyl tetrazolium (MTT) and flow cytometry(FCM). Dose-effect relationship parameters and combination index(CI) were calculated on the median-effect equation and multiple drug effect equation using computer software CalcuSyn. Statistical analysis was performed by the unpaired student's t-test.Results Rapamycin and cisplatin could respectively increase the growth arrest, the proportion of G1 phase and apoptosis of CCL19 induced cancer cells (P <0. 05 ). Under inhibitory concentration 50% (IC50), CI was less than 1, and in IC75, it was more than 1 in PCI-4B cells. In PCI-37B cells, under IC75, CI was less than 1, and in IC90, it was more than 1. Conclusions Rapamycin and cisplatin can inhibit CCL19-regulated PCI-4B and PCI-37B cells' survival. The two drugs have synergistic effects when used in combination. 相似文献
94.
目的 分析颌面部巨大血管畸形的临床特点及治疗方法,探讨放疗在血管畸形治疗中的可行性.方法 回顾分析2000年1月至2008年1月浙江大学医学院附属第二医院施行三维立体定向适形放射治疗的颌面部巨大血管畸形6例的临床资料,并主要根据影像检查与临床体检结果判断疗效.结果 6例患者在术中、术后无严重并发症,均对治疗后面部外形满意,MRI示病变范围缩小,甚至消失.随访0.5~9年,6例患者均无明显复发迹象.无一例出现视器损伤、张口受限等放疗并发症.结论 三维立体定向适形放疗可以作为一种安全有效治疗颌面部巨大血管畸形的方法.Abstract: Objective To discuss the clinical use of radiotherapy in the treatment of giant vascular malformation. Methods Six patients with giant vascular malformation in oral and maxillofacial region were treated by three dimensional radiation therapy in Department of Stomatology, The Second Affiliated Hospital,School of Medicne, Zhejiang University in the last ten years and the cilinical data were reviewed. The treatment results were evaluated by clinical examination and radiology. Results No complication was observed during and after the radiotherapy. All patients were satisfied with the aesthetic results. The lesions in MRI were all reduced and even disappeared. There was no sign of recurrence during the follow-up period.Conclusions Three dimensional radiotherapy is safe and effective for oral and maxillofical vascular malformation. 相似文献
95.
96.
类探讨增进牙龈上皮细胞在钛表面附着的因素,将基底膜提物Matrigel涂在光滑纯钛片表面,扫描电镜观察原代培养的人牙龈上皮细胞在涂Matrigel 钛表面和光滑钛表面的伸展情况。 相似文献
97.
Aim To evaluate human pulp tissue response following direct pulp capping with a self-etching adhesive: Clearfil SE BOND (SB).
Methodology Forty-five sound teeth from 20 subjects were used. Forty-one teeth had their pulp mechanically exposed at the base of a Class 1 cavity preparation and were divided into two groups: group 1, teeth were capped with SB ( n = 21), and group 2, with calcium hydroxide cement (CH) ( n = 20). Four teeth were maintained intact as an untreated control group. After 7, 30 and 90 days, respectively, 15 teeth were extracted and processed for light microscopic examination. Pulp healing and bacterial microleakage were assessed by haematoxylin and eosin, Masson trichrome and Brown and Brenn stain techniques. The data were analysed statistically by using the Mann–Whitney U test.
Results After the 7-day observation period, the inflammatory reaction in the SB group was slight and significantly less severe than that of the CH group ( P < 0.05). After the 30- and 90-day observation periods, the inflammatory reaction was slight in both groups, but specimens with dentine bridge formation in the SB group were significantly less common than those in the CH group ( P < 0.05).
Conclusions Clearfil SB had good biocompatibility with human pulp tissue, but its ability to induce reparative dentine was significantly lower than that of calcium hydroxide. 相似文献
Methodology Forty-five sound teeth from 20 subjects were used. Forty-one teeth had their pulp mechanically exposed at the base of a Class 1 cavity preparation and were divided into two groups: group 1, teeth were capped with SB ( n = 21), and group 2, with calcium hydroxide cement (CH) ( n = 20). Four teeth were maintained intact as an untreated control group. After 7, 30 and 90 days, respectively, 15 teeth were extracted and processed for light microscopic examination. Pulp healing and bacterial microleakage were assessed by haematoxylin and eosin, Masson trichrome and Brown and Brenn stain techniques. The data were analysed statistically by using the Mann–Whitney U test.
Results After the 7-day observation period, the inflammatory reaction in the SB group was slight and significantly less severe than that of the CH group ( P < 0.05). After the 30- and 90-day observation periods, the inflammatory reaction was slight in both groups, but specimens with dentine bridge formation in the SB group were significantly less common than those in the CH group ( P < 0.05).
Conclusions Clearfil SB had good biocompatibility with human pulp tissue, but its ability to induce reparative dentine was significantly lower than that of calcium hydroxide. 相似文献
98.
Wu Ding-Kwo Shih Pual Ming-Chen Chiang I-Chan Kuo Yu-Ting Hsieh Tsyh-Jyi Liu Gin-Chung 《Oral Radiology》2003,19(1):75-82
Oral Radiology - To evaluate the feasibility, safety, and efficacy of endovascular interventions in the emergent management of life-threatening hemorrhage associated with head and neck neoplasm.... 相似文献
99.
镧、铈、氟在抑制人离体牙根面脱矿中作用的比较研究 总被引:5,自引:0,他引:5
作者采用含镧(La)、铈(Ce)、氟(F)的脱矿液,在体外模拟口腔pH循环变化的环境中对离体人牙根面进行抑制脱钙的实验研究,并采用化学及能谱分析手段,对La,Ce,F在根面的抑制脱钙作用进行定量分析。结果显示,这三种微量元素对根面均有明显的抑制脱钙作用,但F较La、Ce的抑制作用强.该研究还从晶体物理化学角度对La、Ce、F的抑制脱矿作用的机理进行探讨。 相似文献
100.
This in vitro study compared the results of clinical examination (abbreviation CE) and the three radiological methods (i.e RVG-radiovisiography) on occlusal and proximal caries diagnosis,using pathological observation as the final standard.The results are:on occlusal caries diagnosis,CE provide the most accordant result to the pathological result.There are statistically significant differences between SR and CE,BW and CE.1st suggests that to occlusal caries diagnosis,CE is still a convenient and efficient way.On proximal caries diagnosis,there are statistically significant differences between SR and CE,BW and CE.BW has the most coincident result with pathological one. 相似文献