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Han JB  Tao ZZ  Chen SM  Kong YG  Xiao BK 《Cancer letters》2011,309(2):162-169
RNA interference (RNAi) is an evolutionary conserved mechanism for specific gene silencing. There are currently numerous cancer therapy clinical trials based on RNAi technology. Using an adenoviral system as a delivery mediator of RNAi, we investigated the therapeutic effects of targeting three genes simultaneously in vitro and in vivo. In this study, we constructed an recombinant adenoviral shRNA expression system as Adv-pEGFP-shVEGF-shTERT-shBcl-xl for multi-genes silencing. Our results showed that the adenoviral vector can achieve above 90% of transfection efficiency and induced obvious apoptosis in CNE-2 cell both in vitro and in vivo compared with targeting the TERT alone or controlled group.  相似文献   
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The primary mutation m.3460G>A occurs with a very low frequency (∼1%) in Chinese patients with Leber hereditary optic neuropathy (LHON). Up to now, there is no comprehensive study of Chinese patients harboring this mutation. We characterized six unrelated probands with m.3460G>A in this study, which were identified from 1,626 patients with LHON or suspected with LHON. The overall penetrance of LHON (25.6% [10/39]) in four pedigrees with m.3460G>A was substantially lower than those families with m.11778G>A (33.3% [619/1859]) as reported in our previous study. Intriguingly, family Le688 with a heteroplasmic m.3460G>A presented a lower penetrance (12.5%) than the other three families with a homoplasmic mutation. There is an elevated gender bias (affected male to affected female = 4:1) in the four families with m.3460G>A compared to those LHON families with m.11778G>A (2.4:1). Complete mtDNA sequencing indicated that the six matrilines belonged to haplogroups B4d1, F2, A5b, M12a, D4b2b, and D4b2, respectively. We did not identify any potential secondary mutation(s) that will affect or be associated with the penetrance of LHON in the six probands by using an evolutionary analysis and protein secondary-structure prediction. Taken together, our results suggested that the m.3460G>A mutation occurred multiple times in Chinese LHON patients. The heteroplasmic status of mutation m.3460G>A might influence the penetrance of LHON in family Le688.  相似文献   
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Tian W  Han X  Liu B  Li Q  Hu L  Li ZY  Yuan Q  He D  Xing YG 《中华医学杂志(英文版)》2010,123(21):2969-2973
Background Theoretic advantages of cervical disc arthroplasty include preservation of normal motion and biomechanics in the cervical spine, and reduction of adjacent-segment degeneration. The clinical and radiographic effects of cervical disc arthroplasty in short term have been ascertained. The aim of this study is to research the data of mid-term results.Methods In this prospective cohort study, 50 patients who underwent cervical disc arthroplasty from December 2003 to January 2006 were enrolled. There were 39 patients who received 1-level disc arthroplasty, and 11 patients received 2-level disc arthroplasty, with an average age of 50.9 years (range from 29 to 73). The median follow-up was 41.85months (range from 36.00-55.63 months). Patients were followed prospectively with respect to their symptoms,neurologic signs, and radiographic results.Results The median value of Japanese Orthopaedic Association (JOA) score was 14.0 before surgery, and 16.5 at the most recent follow-up (P 〈0.01). The median value of the recovery rate of the JOA score was 92.2%. The preoperative range of motion (ROM) at the indexed level was (10.40±4.97)°, which has significantly correlated with the most recent follow-up ROM which was (8.56±4.76)° (P 〈0.05, r=0.33). The ROM at the operative level at the most recent follow-upwas greater than the value at the 3-month follow-up of (7.52±3.37)° (P 〈0.05). The preoperative functional spinal unit (FSU) angulation was (-0.96±6.52)°, which was not significantly correlated with that of the most recent follow-up value of (-2.65±7.95)° (P 〈0.01, r=0.53). The preoperative endplate angulation was (2.61±4.85)°, which had no significant correlation with that of the most recent follow-up value of (0.71±6.41)° (p 〉0.05).Conclusions The clinical and radiographic results of cervical disc arthroplasty are good in mid-term follow-up. The normal range of motion of the operated level and the biomechanics in the cervical spine are well preserved.  相似文献   
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AIM: To determine the extent of colorectal cancer (CRC) mortality and the association between demographic characteristics and CRC mortality in Inner Mongolia.METHODS: Data were collected from the Death Registry System, maintained by the Inner Mongolia Centers for Disease Control and Prevention, from 2008 to 2012. Deaths were classified according to the International Classification of Disease, 10th Revision. Years of life lost, average years of life lost (AYLL), and mortality were calculated over the five years between 2008 and 2012. A conditional logistic regression model was used to analyze the association between marital status, occupational status, education level, area of residence, and the risk of CRC.RESULTS: The AYLL of CRC was 17.39 years. The average mortality of CRC was 5.6/100000. People living in urban areas and having a higher education level had a significantly higher risk of CRC (OR = 1.74 and 95%CI: 1.29-2.35, P < 0.001 and OR = 2.39, 95%CI: 1.76-3.25, P < 0.001, respectively). People who were employed had a lower risk of CRC (OR = 0.64, 95%CI: 0.48-0.86, P = 0.003). The mortality of CRC was positively correlated with the education level (P < 0.001). No statistically significant association was observed between marital status and CRC risk (P = 0.259).CONCLUSION: Living in urban areas, higher education level and unemployment are associated with CRC mortality in Inner Mongolia.  相似文献   
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背景:国外学者报道人群骨量20%归于环境因素,80%归于遗传因素,骨密度的种族及民族差异是很明显的。   目的:调查云南红河地区哈尼族跟骨定量超声测量,分析其与体质量及体质量指数之间关系。 方法:采取随机整群抽样和调查者入户调查的方式对云南省红河地区哈尼族人群300名进行抽样调查,其中男109名,女性191名。现场访谈填写调查表并测量血压、身高、腰围、体质量等,同时均用Achilles Express跟骨定量超声测量仪测量被调查者的右侧跟骨超声速度,并进行相关性分析。 结果与结论:被调查的人群体质量平均为(46.39±8.44) kg,体质量指数平均为(21.07±3.21) kg/m2,右跟骨定量超声传导速度值为(1 512.38±36.77) m/s。相关分析显示,右跟骨定量传导速度值与跟骨密度T值相关性高,可以预测跟骨骨密度。跟骨定量超声传导速度值除与年龄呈负相关,与体质量及体质量指数均呈正相关,并均有显著性意义。提示云南省红河地区哈尼族中老年人的跟骨骨密度与体质量及体质量指数有显著的相关关系。  相似文献   
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