A pilot study applying digital radiography for estimating ratio of supported single-root surface area

BACKGROUND: The prognosis of a tooth with periodontitis is affected by the amount of supporting bone. A key factor in retaining a tooth is the ratio of supported root surface. Currently, root surfaces cannot be accurately measured using conventional dental radiographs, which only measure the length of bone support on proximal surfaces. METHODS: Eight extracted, single-rooted teeth were 3-dimensionally digitized using a contact technique for true surface area measurements. Root length, projection area, and pixel values were then measured on digital radiographs. The accuracy of the ratio estimation of supported surface area from linear, area, and pixel values was calculated and compared. RESULTS: The mean error from linear estimation was 7.9%; the mean error from area estimation was 1.0%; and the mean error from pixel value estimation was 1.3%. One-way analysis of variance (ANOVA) showed significant differences in all estimations while Scheffé's analysis further revealed significant differences only in the linear estimation. CONCLUSIONS: A three-dimensional digitizing device could be used as a non-destructive method of measuring root surface area. The ratio of supported single-root surface area could be estimated with high accuracy from the projected area data acquired on the digital dental radiographs. The thickness data as reflected from the pixel values in the digital images did not improve the estimation accuracy. Estimations using only length data yielded significantly less accuracy. Digital dental x-ray images provide the potential for estimating the ratio of supported root surface efficiently.     

Cancer-promoting effect of Taiwan betel quid in hamster buccal pouch carcinogenesis

OBJECTIVE: To investigate the cancer-promoting effect of Taiwan betel quid in hamster buccal pouch carcinogenesis.
MATERIALS AND METHODS: Two hundred and fifty-two non-inbred mate adult Syrian golden hamsters were randomly divided into six groups, each containing forty-two animalS. A treatment regimen over a 14-week experimental period was employed with six animals per group being killed at seven different periods (every 2 weeks). The right buccal pouch of each animal was painted three times a week with various combinations of 7, 12-dimethylbenz[a]anthracene (DMBA), Taiwan betel quid extract, dimethyl sulfoxide (DMSO) and mineral oil.
RESULT: Both the number and size of tumors in animals concurrently treated with DMBA and betel quid were significantly higher than those in animals treated with DMBA alone in each killing period of 8, 10, 12 and 14 weekS. No visible tumors but hyperkeratosis and acanthosis were observed in pouches treated with betel quid alone for all killing periods.
CONCLUSION: Our results indicate Taiwan betel quid may be a co-carcinogen in human oral carcinogenesis, if extrapolation can be made from the current animal study.     

In Healthy Adults,Biological Activity of Vitamin D,as Assessed by Serum PTH,Is Largely Independent of DBP Concentrations

Vitamin D insufficiency, as measured by 25‐hydroxyvitamin D (25[OH]D) levels, has been associated with important health outcomes. The majority of vitamin D in circulation is bound to vitamin D–binding protein (DBP) and albumin, and recent genetic studies have demonstrated that serum DBP is a major determinant of 25(OH)D concentrations in adults. The impact of circulating DBP levels on vitamin D's biologic action, is unclear, but is of particular relevance to vitamin D epidemiology, because a lack of control for DBP levels could strongly influence the association of vitamin D with disease. Serum parathyroid hormone (PTH) levels can act as a biological readout of 25(OH)D activity. We therefore assessed the relationship between serum total and free 25(OH)D and PTH with and without adjusting for DBP, in 2073 subjects of European descent. Total 25(OH)D levels correlated positively (r = 0.19, p = 1.8 × 10^?17) with DBP, whereas the free 25(OH)D correlated negatively (r = ?0.14, p = 5.0 × 10^?12). Total and free 25(OH)D levels correlated negatively with PTH (r = ?0.29, p = 1.3 × 10^?39; r = ?0.26, p = 1.9 × 10^?33, respectively). Including age, body mass index (BMI), sex, estimated glomerular filtration rate, calcium, and season of blood draw as covariates, total 25(OH)D levels were significantly associated with log‐transformed PTH (lnPTH) levels (linear term: β = ?0.010, p < 0.0001, squared term: β = 0.00004, p < 0.0001) and this association was not changed by adjusting for DBP. These findings provide evidence that in a largely vitamin D–sufficient cohort, the biological effect of vitamin D on PTH levels is mainly independent of DBP concentration. Accordingly, this study may provide useful information for studies investigating the relationship between vitamin D, DBP, and disease. © 2014 American Society for Bone and Mineral Research.     

电刺激小脑顶核促进大脑中动脉缺血鼠共移植体中神经干细胞向神经元的分化

目的:向大脑中动脉缺血大鼠植入神经干细胞,探讨电刺激小脑顶核与神经干细胞共移植体对其向神经元分化的影响。方法:实验于2005-08/2006-11在佳木斯大学神经科学研究所完成。①选取同一基因背景大鼠72只,随机数字表法分成3组:神经干细胞移植组、电刺激 神经干细胞组、电刺激 神经干细胞共移植体组,24只/组。②另选取出生24h内的Wistar鼠1只用于神经干细胞的分离,制备单细胞悬液,调整细胞密度为5×108L-1,置于10mg/L的Brdu完全培养液中孵育72h。神经干细胞共移植体由神经干细胞、层粘连蛋白和血管内皮细胞构成,由本实验室提供并鉴定。③各组大鼠于造模前1d麻醉后行小脑顶核刺激,以前囟为零点、正中线向后11.6mm、正中线向右1.2mm。给予直角方波脉冲刺激,电流强度为50μA,频率80Hz,时程1h。④各组大鼠均采用线栓法建立局灶性脑缺血动物模型。造模1d后,分别将培养的神经干细胞及共移植体细胞浓度调整为2×1010 L-1,于缺血纹状体侧缺血半暗带区垂直进针,进入5.0mm后缓慢推入细胞悬液,神经干细胞移植组、电刺激 神经干细胞组移植神经干细胞悬液10μL,电刺激 神经干细胞共移植体组移植神经干细胞共移植体悬液10μL,移植速度为0.5μL/min,留针10min后缓慢拔针。⑤各组分别于移植后3,7,14,60d观察神经干细胞移入脑内后分化成神经元的情况。胞核呈绿色荧光、胞质呈红色荧光的为Brdu-神经元特异性烯醇化酶双阳性细胞,代表移植入的神经干细胞所分化的神经元。结果:72只同一基因背景大鼠均进入结果分析。①与神经干细胞移植组比较,移植后7,14,60d电刺激 神经干细胞组、电刺激 神经干细胞共移植体组Brdu-神经元特异性烯醇化酶双阳性细胞百分率均明显升高(F=12.44～25.18,P均<0.05)。移植后3,7,14,60d电刺激 神经干细胞共移植体组Brdu-神经元特异性烯醇化酶双阳性细胞百分率均明显高于电刺激 神经干细胞组(F=8.19～25.18,P均<0.05)。②随移植时间的延长,各组Brdu-神经元特异性烯醇化酶双阳性细胞形态均逐渐增大,至移植后60d时细胞周边可见突起。结论:大脑中动脉缺血模型鼠移植入神经干细胞后,电刺激小脑顶核能够对神经干细胞向神经元的分化产生促进作用,且共移植体与电刺激小脑顶核具有协同效应。     

细胞移植治疗帕金森病的研究进展

目的:根据近年细胞移植治疗帕金森病的近况,认识细胞移植治疗帕金森病的最新进展及临床应用前必须解决的技术难题。资料来源:应用计算机检索Pubmed 2000-01/2006-10细胞移植治疗帕金森病的文章,检索词为"Cells transplantation,Parkinson disease",并限定文献种类为English。资料选择:对资料进行初审,选取包括细胞移植与帕金森病相关的文献,开始查找全文。纳入标准:①细胞移植在神经系统疾病中的应用。②细胞移植与帕金森病。排除标准:综述文献、重复研究、Meta分析类文章。资料提炼:共收集到175篇关于细胞移植与帕金森病的文献,纳入30篇文献。资料综合:细胞移植治疗帕金森病的主要细胞来源有肾上腺髓质细胞、胎儿中脑腹侧组织细胞、异种移植、神经干细胞、骨髓干细胞、胚胎干细胞等。其临床应用前仍存在许多技术难题,如移植物的来源、移植部位与方法、移植环境等。随着这些基础研究和临床治疗上难题的解决,细胞移植必将成为治疗帕金森病的重要手段。结论:细胞移植尤其是胚胎干细胞的应用,将为帕金森病的治疗带来新的曙光。     

Kallistatin Ameliorates Influenza Virus Pathogenesis by Inhibition of Kallikrein-Related Peptidase 1-Mediated Cleavage of Viral Hemagglutinin

Proteolytic cleavage of the hemagglutinin (HA) of influenza virus by host trypsin-like proteases is required for viral infectivity. Some serine proteases are capable of cleaving influenza virus HA, whereas some serine protease inhibitors (serpins) inhibit the HA cleavage in various cell types. Kallikrein-related peptidase 1 (KLK1, also known as tissue kallikrein) is a widely distributed serine protease. Kallistatin, a serpin synthesized mainly in the liver and rapidly secreted into the circulation, forms complexes with KLK1 and inhibits its activity. Here, we investigated the roles of KLK1 and kallistatin in influenza virus infection. We show that the levels of KLK1 increased, whereas those of kallistatin decreased, in the lungs of mice during influenza virus infection. KLK1 cleaved H1, H2, and H3 HA molecules and consequently enhanced viral production. In contrast, kallistatin inhibited KLK1-mediated HA cleavage and reduced viral production. Cells transduced with the kallistatin gene secreted kallistatin extracellularly, which rendered them more resistant to influenza virus infection. Furthermore, lentivirus-mediated kallistatin gene delivery protected mice against lethal influenza virus challenge by reducing the viral load, inflammation, and injury in the lung. Taking the data together, we determined that KLK1 and kallistatin contribute to the pathogenesis of influenza virus by affecting the cleavage of the HA peptide and inflammatory responses. This study provides a proof of principle for the potential therapeutic application of kallistatin or other KLK1 inhibitors for influenza. Since proteolytic activation also enhances the infectivity of some other viruses, kallistatin and other kallikrein inhibitors may be explored as antiviral agents against these viruses.