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991.
Zhigang Zhou Jingjing Qin Junwei Tang Bo Li Qiming Geng Weiwei Jiang Wei Wu Virender Rehan Weibing Tang Xiaoqun Xu Yankai Xia 《Journal of pediatric surgery》2013
Background/Purpose
Hirschsprung's disease (HSCR) is a congenital disorder characterized by the absence of intramural ganglion cells which are highly associated with impaired proliferation and migration of neural crest cells. Whether methyl CpG binding protein 2 (MeCP2) is related with HSCR still remains unknown. This study investigates the involvement of MeCP2 in HSCR.Methods
Quantitative real time PCR and western blot were used to detect the expression level of MeCP2 both in the aganglionic/diseased segment and the ganglionic/normal segment. In vitro assays we used siRNAs to knock-down the expression of MeCP2 in SH-SY5Y cell lines, and furthermore, MTT and transwell assays were used to detect the proliferation and migration ability, respectively. In addition, bisulfite sequencing (BSP) and miRNA analysis were used to examine why MeCP2 is decreased in HSCR samples.Results
MeCP2 exhibited a lower expression level in tissues of HSCR patients compared with the controls. The down-regulation may also suppress the proliferative ability of the cells. However, there was no significant difference in the MeCP2 methylation level between cases and controls. Similarly, there was no difference between cases and controls in miRNA-34b (miR-34b) which is predicted to regulate MeCP2 through complementary binding to the 3′-untranslated region of MeCP2.Conclusion
Our results indicated that an aberrant decreased level of MeCP2 may play an important role in the pathogenesis of HSCR. 相似文献992.
993.
Papadopoulos N Martin J Ruan Q Rafique A Rosconi MP Shi E Pyles EA Yancopoulos GD Stahl N Wiegand SJ 《Angiogenesis》2012,15(2):171-185
Pharmacological inhibition of VEGF-A has proven to be effective in inhibiting angiogenesis and vascular leak associated with
cancers and various eye diseases. However, little information is currently available on the binding kinetics and relative
biological activity of various VEGF inhibitors. Therefore, we have evaluated the binding kinetics of two anti-VEGF antibodies,
ranibizumab and bevacizumab, and VEGF Trap (also known as aflibercept), a novel type of soluble decoy receptor, with substantially
higher affinity than conventional soluble VEGF receptors. VEGF Trap bound to all isoforms of human VEGF-A tested with subpicomolar
affinity. Ranibizumab and bevacizumab also bound human VEGF-A, but with markedly lower affinity. The association rate for
VEGF Trap binding to VEGF-A was orders of magnitude faster than that measured for bevacizumab and ranibizumab. Similarly,
in cell-based bioassays, VEGF Trap inhibited the activation of VEGFR1 and VEGFR2, as well as VEGF-A induced calcium mobilization
and migration in human endothelial cells more potently than ranibizumab or bevacizumab. Only VEGF Trap bound human PlGF and
VEGF-B, and inhibited VEGFR1 activation and HUVEC migration induced by PlGF. These data differentiate VEGF Trap from ranibizumab
and bevacizumab in terms of its markedly higher affinity for VEGF-A, as well as its ability to bind VEGF-B and PlGF. 相似文献
994.
Hua-Rong Tang Xian-Qin Luo Gang Xu Yan Wang Zhi-Jun Feng Hui Xu Ya-Wei Shi Qin Zhang Li-Guang Wu Chun-Quan Xue Cheng-Wei Wang Chao-Yang Wu 《World journal of gastroenterology : WJG》2012,18(48):7319-7326
AIM:To elucidate high mobility group-box 3(HMGB3) protein expression in gastric adenocarcinoma,its potential prognostic relevance,and possible mechanism of action.METHODS:Ninety-two patients with gastric adenocarcinomas surgically removed entered the study.HMGB3 expression was determined by immunohistochemistry through a tissue microarray procedure.The clinicopathologic characteristics of all patients were recorded,and regular follow-up was made for all patients.The inter-relationship of HMGB3 expression with histological and clinical factors was analyzed using nonparametric tests.Survival analysis was carried out by Kaplan-Meier(log-rank) and multivariate Cox(Forward LR) analyses between the group with overexpression of HMGB3 and the group with low or no HMGB3 ex-pression to determine the prognosis value of HMGB3 expression on overall survival.Further,HMGB3 expression was knocked down by small hairpin RNAs(shRNAs) in the human gastric cancer cell line BGC823 to observe its influence on cell biological characteristics.The MTT method was utilized to detect gastric cancer cell proliferation changes,and cell cycle distribution was analyzed by flow cytometry.RESULTS:Among 92 patients with gastric adenocarcinomas surgically removed in this study,high HMGB3 protein expression was detected in the gastric adenocarcinoma tissues vs peritumoral tissues(P 0.001).Further correlation analysis with patients' clinical and histology variables revealed that HMGB3 overexpression was obviously associated with extensive wall penetration(P = 0.005),a positive nodal status(P = 0.004),and advanced tumor-node-metastasis(TNM) stage(P = 0.001).But there was no correlation between HMGB3 overexpression and the age and gender of the patient,tumor localization or histologic grade.Statistical Kaplan-Meier survival analysis disclosed significant differences in overall survival between the HMGB3 overexpression group and the HMGB3 no or low expression group(P = 0.006).The expected overall survival time was 31.00 ± 3.773 mo(95%CI = 23.605-38.395) for patients with HMGB3 overexpression and 49.074 ± 3.648 mo(95%CI = 41.925-57.311) for patients with HMGB3 no and low-level expression.Additionally,older age(P = 0.040),extensive wall penetration(P = 0.008),positive lymph node metastasis(P = 0.005),and advanced TNM tumor stage(P = 0.007) showed negative correlation with overall survival.Multivariate Cox regression analysis indicated that HMGB3 overexpression was an independent variable with respect to age,gender,histologic grade,extent of wall penetration,lymph nodal metastasis,and TNM stage for patients with resectable gastric adenocarcinomas with poor prognosis(hazard ratio = 2.791,95%CI = 1.233-6.319,P = 0.019).In the gene function study,after HMGB3 was knocked down in the gastric cell line BGC823 by shRNA,the cell proliferation rate was reduced at 24 h,48 h and 72 h.Compared to BGC823 shRNA-negative control(NC) cells,the cell proliferation rate in cells that had HMGB3 shRNA transfected was significantly decreased(P 0.01).Finally,cell cycle analysis by FACS showed that BGC823 cells that had HMGB3 knocked down were blocked in G1/G0 phase.The percentage of cells in G1/G0 phase in BGC823 cells with shRNA-NC and with shRNA-HMGB3 was 46.84% ± 1.7%,and 73.03% ± 3.51% respectively(P = 0.001),whereas G2/M cells percentage decreased from 26.51% ± 0.83% to 17.8% ± 2.26%.CONCLUSION:HMGB3 is likely to be a useful prognostic marker involved in gastric cancer disease onset and progression by regulating the cell cycle. 相似文献
995.
996.
目的 分析退行性下睑内翻眼轮匝肌缩短矫正术欠矫原因,评估再次手术修补的效果。方法 收集2008~2017年我院退行性眼睑内翻行眼轮匝肌缩短矫正手术欠矫病例27例(27眼)。分析欠矫原因,并根据其原因选择相应手术方式,观察再次矫正的手术效果。结果 退行性眼睑内翻原因和修补方式为:下睑缩肌断裂未修补15例,给予下睑缩肌修复;水平松弛未矫正7例,给予外眦韧带缩短手术;5例同时存在下睑缩肌断裂和水平松弛,行下睑缩肌修复联合外眦韧带缩短手术。再次手术随访时间内[(18.74±12.11)个月]所有患者症状消失,眼睑位置正常。结论 退行性眼睑内翻眼轮匝肌缩短手术欠矫的原因为手术方式选择不完全正确,眼睑退行性改变因素未得到充分矫正。发生欠矫时,应仔细分析其原因,选择合适的手术方式,仍可以获得良好的矫正效果。 相似文献
997.
角膜散光的精准评估在屈光和白内障手术中具有重要的临床意义。以往由于理论认识的不足和检查设备的局限性,低估了角膜后表面散光(PCA)对整体角膜散光评估所带来的影响。近年来,基于不同原理的多种设备实现了对角膜后表面信息的直接或间接采集,其在临床和科研中的广泛应用使PCA的分布特点及规律逐渐清晰。现对PCA的评估方法和临床特征作一综述,旨在提高临床实践中对PCA的认识和重视。 相似文献
998.
Efficacy of wet-lab training versus surgical-simulator training on performance of ophthalmology residents during chopping in cataract surgery 下载免费PDF全文
Ya-Guang Hu Qiu-Ping Liu Ning Gao Chang-Rui Wu Jian Zhang Li Qin Jing-Ming Li 《国际眼科》2021,14(3):366-370
AIM: To analyze whether wet-lab training(WLT) or surgical-simulator training(SST) is better for ophthalmology residents to master the chopping technique.METHODS: Sixty ophthalmology residents(in their second year) and three cataract surgeons participated in the study. The residents were randomly separated into two groups, WLT group and SST group. The residents in WLT group were asked to perform 10 trials of chopping using pig eyes and scored by the surgeons, and then they performed and scored using simulator for one time. The residents in SST group underwent 10 trials of chopping using simulator, and the simulator scored each trail. Then, this group were asked to perform the chopping using pig eyes and scored by the surgeons. At last, we investigated the residents’ satisfaction about the training.RESULTS: The demographic characteristics had no significant differences between the two groups. Recorded by the simulator, the residents in SST group got significantly higher overall score(83.90±1.31) than WLT group(78.73±1.92, P=0.03). And the residents in SST group got less corner area injured, and they spend less time than WLT group(P<0.05). Moreover, the residents in WLT group used more ultrasonic energy value than SST group(P=0.03). However, scored by the surgeons, the residents in two groups got nearly the same overall score. The residents in WLT group performed better on the frequencies of posterior capsule torn and incisional stress(P=0.03, 0.008, respectively). In the survey, the residents in two groups held the same opinion that the training was helpful and they strongly recommended this training. And all of them enjoyed the training, and enjoyed being randomized in their own group. However, with respect to the realistic character, the residents thought that WLT was better than SST(P<0.001).CONCLUSION: Both of the Eyesi surgical-stimulator and the wet-lab improve the residents’ chopping ability and each has its own advantages. The combination of the two training ways could be considered to be a part of the training curriculum for new residents. 相似文献
999.
Zhan-Hu Cui Shuang-Shuang Qin Er-Huan Zang Chao Li Li Gao Quan-Chao Li Yun-Long Wang Xian-Zhang Huang Zhong-Yi Zhang Min-Hui Li 《RSC advances》2020,10(19):11463
Lamiophlomis rotata (Benth.) Kudo is a herbaceous plant of the family Lamiaceae, subfamily Lamioideae. Approximately, 127 chemical constituents have been isolated and identified from L. rotata, including iridoids, flavonoids, phenylethanoid glycosides, polysaccharides, and organic acids. These chemical constituents have extensive pharmacological properties, which include anti-nociceptive, haemostatic, anti-inflammatory, anti-tumour, immunomodulatory, antioxidant, and cardio-protective activities. Documentation of its historical use in traditional medicine and contemporary phytochemical and pharmacological research indicate that L. rotata has significant potential in therapeutic and health care applications. Both whole extracts and individual chemical components isolated from this plant exhibit a wide range of biological activities that warrant further investigation. These investigations can be assisted by careful review of existing traditional knowledge from diverse cultural backgrounds. A new search for chemical and biological markers and reinforced protection of the germplasm resources of L. rotata are also important to ensure targeted and sustainable use of this medicinal resource. The aim of this review was to provide comprehensive information on the botanical characteristics, traditional uses, ethnopharmacology, chemical and pharmacological properties, toxicity profile, and conservation status of L. rotata, to improve understanding of its mechanisms of action so that novel therapeutic agents may be developed from this plant.The useful information of Lamiophlomis rotata (Benth.) Kudo was summarized, which provided a basis for the development of new therapeutic drugs for this plant. 相似文献
1000.
Mochao Xiao Daifeng Lu Jiali Tian Yang Yu Qin Zhang Lili Zhang Dong Chang 《RSC advances》2020,10(17):10245
Acute myocardial infarction (AMI) is a complication of atherosclerosis that takes place in coronary arteries. Cardiac endothelial cells play a significant role in the pathogenesis of AMI. Oxygen-glucose deprivation/reperfusion (OGD/R) is widely used as a model to simulate AMI in vitro. Recently, antidiabetic GLP-1 receptor agonists have been shown to exert pleiotropic effects that modulate cardiovascular complications. In this study, we investigated the vascular effect of lixisenatide. We show that pre-treatment of endothelial cells with lixisenatide protected them from OGD/R-induced cytotoxicity and improved their viability. Pre-treatment with lixisenatide ameliorated OGD/R-induced ROS accumulation and disturbed endothelial tube formation. At the molecular level, lixisenatide mitigated OGD/R-induced reduced eNOS expression and NO production but further promoted the expression of the anti-oxidant regulators Nrf2 and HO-1. Mechanistically, we confirmed that the PI3K/Akt pathway is essential for mediating the effects of lixisenatide, and blockage of PI3K/Akt using the inhibitor LY294002 abolished the ameliorative effect of lixisenatide on ROS production and impaired tube formation. These data indicate that lixisenatide possesses a beneficial effect on the vasculature in a model of ischemia-induced endothelial injury. We conclude that the GLP-1 receptor agonist lixisenatide has pleiotropic properties that can modulate vascular function independent of its anti-glycemic effect.Acute myocardial infarction (AMI) is a complication of atherosclerosis that takes place in coronary arteries. 相似文献