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Objective To detect the influence of fluoride on the expression TM9SF1 mRNA and Ras mRNA of osteoblasts. Methods The third generation of primary cultured osteoblasts were exposed to a series concentrations of 0,2.5,5.0, 10.0,20.0 mg/L fluoride for 10 days. The influence of different doses of fluorine on the expression of TM9SF1 mRNA and Ras mRNA of osteoblasts cultured in vitro was investigated by SYBR Green I methods. Results The osteoblasts of the control group and the 2.5 mg/L group were in the shape of long spindle, triangle or irregular polygon and had processes, and the cytoplasm was translucent, adjacent cells affixed to each other under light microscope. Those of the 20.0 mg/L group shaped as long spindle or irregular polygon, and some vacuolization and granular materials appeared in cytoplasm. The number of the cells decreased and the volume increased significantly. After exposed to fluoride for 10 days, osteoblasts of 2.5 mg/L group morphologically proliferated. There were statistical siguificances between each groups of TM9SF1 mRNA in human osteoblasts(F = 322.82, P < 0.01). The highest in the 2.5 mg/L group(9326.0 ± 115.97), the expression of TM9SF1 mRNA decreased along with the increasing dose of fluorine. There were statistical significances between 5.0, 10.0,20.0 mg/L groups(6495.0 ± 323.9, 4387.5 ± 545.2, 5962.5 ± 536.7) and control group(9221.0 ± 107.5, all P< 0.01). There was a statistical significance between each groups of Ras mRNA in human osteoblasts(F = 703.28, P < 0.01). The highest in the control group, the expression of Ras mRNA decreased along with the increasing of dose of fluorine. There were statistical significance between 2.5, 5.0, 10.0, 20.0 mg/L groups(6144.5 ± 270.82,5603.5 ± 88.39,3181.0 ± 159.81,4067.5 ± 37.4) and control group(6571.0 ± 196.58). Conclusion The influence on TM9SFI mRNA and Ras mRNA expression in osteoblasts correlates with the dose of fluorine.
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<p><b>OBJECTIVE</b>To investigate the oral health status of freshmen of university students and to guide their oral hygiene behaviors.</p><p><b>METHODS</b>6,575 freshmen of Peking University students were investigated in this study according to the criterion issued by World Health Organization (WHO) on the basic methods of oral health investigation and China oral health epidemiology survey protocol. The inspection item included caries, gingivitis, malocclusions and impacted teeth.</p><p><b>RESULTS</b>In 6,575 freshmen of university students, the prevalence rate of caries, gingivitis, malocclusions and impacted teeth were 35.47%, 60.87%, 19.70% and 24.62%, respectively. There were statistical significance between the prevalence rate of caries, gingivitis, malocclusions and impacted teeth of male and female (chi2=131.94, P<0.001: chi2=216.85, P<0.001; chi2=14.54, P<0.01; chi2=23.56, P<0.001). There were statistical significance between the prevalence rate of caries, gingivitis and impacted teeth of postgraduate and undergraduate (chi2=4.62, P<0.05: chi2=129.56, P<0.001; chi2=178.05, P<0.001), while there was no statistical significance between the prevalence rate of malocclusions of postgraduate and undergraduate (chi2=0.61, P>0.05).</p><p><b>CONCLUSION</b>The oral health status of freshmen of university students are not ideal. It is necessary to strengthen the propaganda education of prevention and protect to freshmen of university students.</p>
Subject(s)
Female , Humans , Male , China , Dental Caries , Health Status , Malocclusion , Oral Health , Oral Hygiene , Prevalence , Students , UniversitiesABSTRACT
Objective To study the proliferation of in vitro cultured mouse chondrocytes exposed to different doses of fluoride.Methods The third generation of primary cultured chondrocytes were exposed to the concentrations of 0,5,10,20,40 mg/L fluoride for 10 days to observe the morphological changes under light microscope and electron microscope to counter the numbers of ehondrocytes and proliferating rote with the growth curve and MTT.Results After exposed to fluoride for 10 days,the proliferation was present in the chondrocytes of the 5,10,20 mg/L groups,and shrinked chromatine and apoptosed ehondrocytes were seen in 40 mg/L group.The absorbance was not significantly different between all groups(F=2.313,P＞0.05);after exposed to fluoride for 48 and 72 hours,there was a significant difference of proliferating ability among 0 mg/L(the contr01)group[(23.5±4.6)%,(29.9±1.7)%],5 mg/L group[(34.6±4.7)%,(45.3±5.9)%],10 mg/L group[(39.9±4.8)%.(56.8±5.5)%],20 mg/L group[(31.8±4.1)%,(38.3±6.5)%]and 40 mg/L group[(28.3±4.3)%,(33.4±4.8)%](F=11.401,25.671,P＜0.05).There wss a significant difference compared with the control group(P＜0.05)with that of 5 and 10 mg/L groups higher than that of 40 mg/L groups(P＜0.05).Conclusions Lower doses of fluoride improve the proliferation of in vitro mouse chondrocyte in a short exposing time,higher doses result in the opposite.