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Transcatheter atrial septal defects and patent foramen ovale closure:Medicare utilization and reimbursements
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作者 Vidit Majmundar Rohan Deo +3 位作者 Ajay Kumar Mishra Peng-Yang Li Marina Byer Rhea Sancassani 《World Journal of Methodology》 2025年第4期225-231,共7页
BACKGROUND The Food and Drug Administration has approved percutaneous atrial septal defect(ASD)and patent foramen ovale(PFO)closure devices for hemodynamically significant interatrial shunts,paradoxical emboli includi... BACKGROUND The Food and Drug Administration has approved percutaneous atrial septal defect(ASD)and patent foramen ovale(PFO)closure devices for hemodynamically significant interatrial shunts,paradoxical emboli including stroke,and decompression sickness.We aimed to study the trends in utilization and reimbursements of transcatheter ASD/PFO closure devices.AIM To analyze trends in utilization and Medicare reimbursements for transcatheter ASD/PFO closure procedures from 2013 to 2022.METHODS A query of administrative data on United States Medicare beneficiaries undergoing transcatheter ASD/PFO was conducted from 2013 to 2022 using the Centers for Medicare and Medicaid Services Part B National Summary Data File.Inflation adjustments were made using the 2023 Consumer Price Index.Trend analysis was quantified using growth rate and simple linear regression calculations.All analyses were performed using Microsoft Excel 16.77.1(2023).RESULTS The annual number of transcatheter ASD/PFO closure procedures increased by 81%since 2013,with an average yearly growth rate of 44%cases per year(P<0.001).Annual Medicare reimbursements for transcatheter ASD/PFO therapies mirrored the annual procedure trends.The per-case reimbursements decreased by 18%,i.e.,$1128.80 in 2013 and$770.21 in 2022(P<0.001).There was a significant drop in the number of procedures in the year 2020,which correlates to the onset of the coronavirus disease 2019 pandemic,followed by a sharp uptick in the number of cases in 2021 and 2022.CONCLUSION Medicare utilization of transcatheter ASD/PFO closure therapies has grown significantly in procedural volume from 2013 to 2022.However,this has been accompanied by a decrease in per-case reimbursements. 展开更多
关键词 Atrial septal defect Patent foramen ovale MEDICARE REIMBURSEMENT Patent foramen ovale closure
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Right-to-left shunt detection in patent foramen ovale:The value of synchronized contrast transcranial Doppler and contrast transthoracic echocardiography
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作者 Yu-Yin Wang Lu Xie +2 位作者 Jun-Bang Feng Yang-Yang Xu Chuan-Ming Li 《World Journal of Radiology》 2025年第5期84-86,共3页
Patent foramen ovale(PFO)is a common congenital heart disorder associated with stroke,decompression sickness and migraine.Combining synchronized contrast transcranial Doppler with contrast transthoracic echocardiograp... Patent foramen ovale(PFO)is a common congenital heart disorder associated with stroke,decompression sickness and migraine.Combining synchronized contrast transcranial Doppler with contrast transthoracic echocardiography has important clinical significance and can improve the accuracy of detecting right-left shunts(RLSs)in patients with PFO.In this letter,regarding an original study presented by Yao et al,we present our insights and discuss how to better help clinicians evaluate changes in PFO-related RLS. 展开更多
关键词 Contrast transcranial Doppler Contrast transthoracic echocardiography Combined multimodal ultrasound Patent foramen ovale Right-to-left shunt
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2025 Chinese Expert Consensus on Clinical Applications of Biodegradable Patent Foramen Ovale Occluders
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作者 Caojin Zhang Haibo Hu +11 位作者 Gangcheng Zhang Qiguang Wang Xiaobin Chen Yingzhang Cheng Qunshan Shen Jie Yuan Wenqi Zhang Yuanshi Li Xuan Zheng Xiangbin Pan Professional Committee of National Quality Management and Control Center for Structural Heart Diseases Professional Committee of Structural Heart Diseases of the National Cardiovascular Disease Expert Committee 《Congenital Heart Disease》 2025年第4期403-420,共18页
Compared with traditional nickel-titanium alloy patent foramen ovale occluders,which are widely used in clinical practice,biodegradable patent foramen ovale occluders have obvious differences in material characteristi... Compared with traditional nickel-titanium alloy patent foramen ovale occluders,which are widely used in clinical practice,biodegradable patent foramen ovale occluders have obvious differences in material characteristics,interventional operation mode and postoperative management strategy.This article gives expert consensus on the selection of clinical indications and standardized operating procedures,so as to standardize the clinical application of biodegradable patent foramen ovale occluders. 展开更多
关键词 Patent foramen ovale BIODEGRADABLE OCCLUDER
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A Novel Transcatheter Suture Closure System for Patent Foramen Ovale:An Experimental Study in Swine
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作者 Su Ye Luxi Guan +7 位作者 Dong Luo Fengwen Zhang Jianhua Lv Qizong Xie Qiao Huang Haiming Wu Haibo Hu Xiangbing Pan 《Congenital Heart Disease》 2025年第2期181-193,共13页
This study aimed to evaluate the feasibility,safety,and efficacy of a noveltranscatheter suture closure system(HaloStitch^(®))for patent foramen ovale(PFO)closure in a swine model.Methods:Thirteen swine underwent... This study aimed to evaluate the feasibility,safety,and efficacy of a noveltranscatheter suture closure system(HaloStitch^(®))for patent foramen ovale(PFO)closure in a swine model.Methods:Thirteen swine underwentexperimental PF0 model creation.All animals received implantationof the transcatheter suture closure system to evaluate procedural success.Comprehensive follow-up over sixmonths included serial ultrasound imaging,histopathological analysis,and gross anatomical exaninationof cardiac specimens.Results:Successful HaloStitch^(®)device implantation was adhieved in 11 of 13 swine.Gross anatomical examination confirrned secure positioning of all sutures in the atrial septum,with noredundancy or thrombus formation.Postoperative ultrasound demonstrated stable suture and staplepositions throughout follow-up,with no evidence of suture breakage,displacement,or thrombus.Stapleswere clearly visualized under ultrasound imaging,Both the atrial septal defect orifice diameter and residualseptal shunt flow velocity decreased significantly during the observation period.Histopathological analysisrevealed partially organized thrombi at the implant head and fibrous connective tissue encapsulation withlocalized inflammatory cell infiltration surrounding the polymer material.Conclsions:The transcathetersuture closure system(HaloStitch^(®))demonstrated feasibility,safety,and biocompatib ility for PFO closure ina swine model,supporting its potential for clinical translation. 展开更多
关键词 Patent foramen ovale transcatheter suture closure system experimental study
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基于OVAL的新型漏洞评估系统 被引量:8
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作者 陈秀真 李建华 《小型微型计算机系统》 CSCD 北大核心 2007年第9期1554-1557,共4页
漏洞评估技术基于防患于未然思想,采用主动探测方法发现系统存在的安全漏洞并提供相应解决方案.针对目前漏洞评估系统存在误报率高、扫描时间长且需要开发攻击代码的缺点,本文提出一种基于OVAL的新型漏洞评估系统.该系统由控制台、数据... 漏洞评估技术基于防患于未然思想,采用主动探测方法发现系统存在的安全漏洞并提供相应解决方案.针对目前漏洞评估系统存在误报率高、扫描时间长且需要开发攻击代码的缺点,本文提出一种基于OVAL的新型漏洞评估系统.该系统由控制台、数据中心和检测代理3大模块组成,这三个模块协同实现漏洞评估.与现有漏洞评估系统相比,具有精度高、对目标系统性能影响小、评估时间短和可扩展性强的优点,而且免除传统漏洞评估系统所需的攻击代码开发工作. 展开更多
关键词 漏洞评估 oval 检测代理 控制台
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从OVAL漏洞信息转换到Nessus扫描插件的研究与实现 被引量:1
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作者 王猛 刘必雄 +1 位作者 许榕生 丁天昌 《计算机系统应用》 2007年第11期27-31,共5页
网络安全漏洞扫描应充分考虑执行的效率和信息的共享。本文通过对OVAL和Nessus的介绍,分析O- VAL Definition与Nessus plugin之间的异同,提出并实现了一种将OVAL公布的漏洞信息转换成Nessus扫描插件的方法,共享了漏洞信息,并提升了漏洞... 网络安全漏洞扫描应充分考虑执行的效率和信息的共享。本文通过对OVAL和Nessus的介绍,分析O- VAL Definition与Nessus plugin之间的异同,提出并实现了一种将OVAL公布的漏洞信息转换成Nessus扫描插件的方法,共享了漏洞信息,并提升了漏洞检测的品质。最后经过实验说明该方法的可行性。 展开更多
关键词 漏洞扫描 oval DEFINITION NESSUS PLUGIN
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OVALS海洋资料同化系统并行计算研究
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作者 卢风顺 宋君强 朱小谦 《计算机工程与科学》 CSCD 北大核心 2010年第1期113-116,共4页
海洋数值预报技术的发展与高性能计算密切相关。为提高OVALS海洋资料同化系统的时效性,本文实现了OVALS系统的并行化。在温盐资料同化模块并行化过程中,本文提出了层优先处理器划分算法,并研究了基于该算法的并行I/O、全局通讯等实现方... 海洋数值预报技术的发展与高性能计算密切相关。为提高OVALS海洋资料同化系统的时效性,本文实现了OVALS系统的并行化。在温盐资料同化模块并行化过程中,本文提出了层优先处理器划分算法,并研究了基于该算法的并行I/O、全局通讯等实现方法;在高度计资料同化模块并行化过程中,设计实现了基于预处理的非规则区域分解算法,较好地实现了OVALS并行计算负载平衡。数值实验表明,OVALS并行系统在36并行规模下取得了17.45的并行加速比。 展开更多
关键词 ovalS海洋资料同化 并行算法 处理器划分 非规则区域分解
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Novel way of patent foramen ovale detection and percutaneous closure by intracardiac echocardiography:A case report
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作者 Kang-Ning Han Shi-Wei Yang Yu-Jie Zhou 《World Journal of Clinical Cases》 SCIE 2022年第29期10559-10564,共6页
BACKGROUND Patent foramen ovale(PFO)is the most common congenital heart disease and is associated with several diseases,including stroke and migraine.PFO diagnosis involves transoesophageal echocardiography,transthora... BACKGROUND Patent foramen ovale(PFO)is the most common congenital heart disease and is associated with several diseases,including stroke and migraine.PFO diagnosis involves transoesophageal echocardiography,transthoracic echocardiography,and transcranial Doppler.Recent studies have shown that intracardiac echocardiography(ICE)can be used to diagnose and guide percutaneous transcatheter closure.CASE SUMMARY A 70-year-old male presented with paroxysmal dizziness and limb weakness for the past 3 mo.Magnetic resonance imaging revealed a history of stroke,and a bubble test revealed the presence of PFO.The patient was then transferred to our hospital for PFO closure.Under ICE guidance,the separation of the septum primum and septum secundum was unclear;we then used a Swartz catheter to confirm PFO by applying physical pressure on the right part of the atrial septum without using any contrast.The ICE continuously and clearly guided the procedure.CONCLUSION ICE can guide PFO closure in patients with a history of stroke.When PFO is not evident under ICE,a Swartz catheter can be used. 展开更多
关键词 Intracardiac echocardiography Patent foramen ovale Percutaneous patent foramen ovale closure Case report
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基于OVAL新型漏洞检测器漏洞库的设计与实现
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作者 占善华 《信息通信》 2012年第4期48-49,共2页
针对目前主流的漏洞扫描技术中漏洞库的不完整,本文提出了一种新型的基于OVAL的漏洞检测器,其漏洞库可根据需要扫描系统软件、硬件和配置信息等,并以此确定系统中存在的安全漏洞。此检查器所能扫描的操作系统很多,该篇文章以RedHat为载... 针对目前主流的漏洞扫描技术中漏洞库的不完整,本文提出了一种新型的基于OVAL的漏洞检测器,其漏洞库可根据需要扫描系统软件、硬件和配置信息等,并以此确定系统中存在的安全漏洞。此检查器所能扫描的操作系统很多,该篇文章以RedHat为载体讲述工作原理和实现。 展开更多
关键词 oval 扫描 漏洞 扫描引擎
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川芎内生菌Pseudeurotium ovale代谢产物研究 被引量:3
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作者 郭文秀 巨凤 +4 位作者 沈芋蓉 谭璐 李新爱 郭大乐 邓赟 《天然产物研究与开发》 CAS CSCD 2022年第2期239-244,共6页
通过大孔树脂柱层析、凝胶柱层析和高效液相色谱等方法对川芎中分离得到的内生菌Pseudeurotium ovale的代谢物进行分离纯化,从中分离得到5个化合物,并通过核磁共振和质谱等波谱学技术手段确认所有化合物的结构,其中包含一个新的化合物4-... 通过大孔树脂柱层析、凝胶柱层析和高效液相色谱等方法对川芎中分离得到的内生菌Pseudeurotium ovale的代谢物进行分离纯化,从中分离得到5个化合物,并通过核磁共振和质谱等波谱学技术手段确认所有化合物的结构,其中包含一个新的化合物4-methoxy-3-methyl-6-(1 E,3 E)-1,3-pentadien-1-yl-2 H-pyran-2-one(1)和四个首次从中分离得到的已知化合物:(2 E,4 E)-1-(2,6-dihydroxy-3,5-dimethylphenyl)-2,4-hexadien-1-one(2)、2-deoxy-sohirnone C(3)、trichodimerol(4)、3,7-dihydroxy-1,9-dimethyl-dibenzofuran(5)。体外抗炎活性测试表明化合物1可抑制经脂多糖(LPS)处理的RAW 264.7细胞中NO、IL-6和TNF-α等炎症因子的分泌。 展开更多
关键词 Pseudeurotium ovale 代谢物 抗炎活性
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NUMERICAL SIMULATION OF ROUND TO OVAL ROLLING PROCESS 被引量:27
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作者 Y. W. Wang, Y. L. King, D. H. Yuan, S. G. Liu and Z. Y. Yu 1 ) University of Science and Technology Beijing, Beijing 100083, China 2) Daye Special Steel Co., Huangshi 435001, China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第2期428-433,共6页
Three dimensional thermal-mechanical coupled elasto-plastic FEM has been used for simulation of round to oval single pass rolling. The analysis was conducted using MARC/AUTOFORCE1. 2 code. The material is assumed to b... Three dimensional thermal-mechanical coupled elasto-plastic FEM has been used for simulation of round to oval single pass rolling. The analysis was conducted using MARC/AUTOFORCE1. 2 code. The material is assumed to be elasto-plastic and it obey the Von Mises yield criterion and Prandtl- Reuss rule. Deformation of the workpiece is simulated in a step-by-step manner,updating the coordinates of material points and the property after each step, so that both nonsteady-state and stendy-state deformation can be simulated. The heat transfter between the workpiece, the rolls, and enviroment and the heat generation due to plastic work and friction force, are considered in the analys- is.Predicted the deformation shape of the workpiece, distributions of strains, stresses, strain rates and temperatures, roll-separating force and roll torque are presented. 展开更多
关键词 bar rolling oval pass elasto-plastic FEM thermal mechanical process
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Clinical relevance of atrial septal aneurysm and patent foramen ovale with migraine 被引量:8
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作者 Lu He Ge-Sheng Cheng +1 位作者 Ya-Juan Du Yu-Shun Zhang 《World Journal of Clinical Cases》 SCIE 2018年第15期916-921,共6页
AIM To test the potential association between atrial septal aneurysm(ASA) and migraine in patent foramen ovale(PFO) closure patients through an observational, singlecenter, case-controlled study.METHODS We studied a t... AIM To test the potential association between atrial septal aneurysm(ASA) and migraine in patent foramen ovale(PFO) closure patients through an observational, singlecenter, case-controlled study.METHODS We studied a total of 450 migraineurs who had rightto-left shunts and underwent PFO closure in a retrospective single-center non-randomized registry from February 2012 to October 2016 on the condition that they were aged 18-45 years old. Migraine was diagnosed according to the International Classification of Headache Disorders, 3^(rd) edition and evaluated using the Headache Impact Test-6(HIT-6). All patients underwent preoperative transesophageal echocardiography, contrast transthoracic echocardiography, and computed tomography or magnetic resonance imaging examinations, with subsequent fluoroscopy-guided PFO closure. Based on whether they have ASA or not, the patients were divided into two groups: A(PFO with ASA, n = 80) and B(PFO without ASA, n = 370). Baseline characteristics and procedural and follow-up data were reviewed. RESULTS Compared to group B, group A had an increased frequency of ischemic lesions(11.3% vs 6.2%, P = 0.038) and migraine with aura(32.5% vs 21.1%, P = 0.040). The PFO size was significantly larger in group A(P = 0.007). There was no significant difference in HIT-6 scores between the two groups before and at the oneyear follow-up after the PFO closure [61(9) vs 63(9), P = 0.227; 36(13) vs 36(10), P = 0.706].CONCLUSION Despite its small sample size, our study suggests that the prevalence of ASA in PFO with migraine patients is associated with ischemic stroke, larger PFO size, and migraine with aura. 展开更多
关键词 Patent foramen ovale MIGRAINE Atrial SEPTAL ANEURYSM Contrast TRANSTHORACIC ECHOCARDIOGRAPHY Right-to-left shunt TRANSESOPHAGEAL ECHOCARDIOGRAPHY
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Hepatic non-parenchymal cells and extracellular matrix participate in oval cell-mediated liver regeneration 被引量:14
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作者 Wei Zhang Xiao-Ping Chen Wan-Guang Zhang Feng Zhang Shuai Xiang Han-Hua Dong Lei Zhang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第5期552-560,共9页
AIM: To elucidate the interaction between non- parenchymal cells, extracellular matrix and oval cells during the restituting process of liver injury induced by partial hepatectomy (PH). METHODS: We examined the lo... AIM: To elucidate the interaction between non- parenchymal cells, extracellular matrix and oval cells during the restituting process of liver injury induced by partial hepatectomy (PH). METHODS: We examined the localization of oval cells, non-parenchymal cells, and the extracellular matrix components using immunohistochemical and double immunofluorescent analysis during the proliferation and differentiation of oval cells in N-2- acetylaminofluorene (2-AAF)/PH rat model. RESULTS: By day 2 after PH, small oval cells began to proliferate around the portal area. Most of stellate cells and laminin were present along the hepatic sinusoids in the periportal area. Kupffer cells and fibronectin markedly increased in the whole hepatic Iobule. From day 4 to 9, oval cells spread further into hepatic parenchyma, closely associated with stellate cells, fibronectin and laminin. Kupffer cells admixed with oval cells by day 6 and then decreased in the periportal zone. From day 12 to 15, most of hepatic stellate cells (HSCs), laminin and fibronectin located around the small hepatocyte nodus, and minority of them appeared in the nodus. Kupffer cells were mainly limited in the pericentral sinusoids. After day 18, the normal liver Iobule structures began to recover.CONCLUSION: Local hepatic microenvironment may participate in the oval cell-mediated liver regeneration through the cell-cell and cell-matrix interactions. 展开更多
关键词 oval cells Liver regeneration EXTRACELLULARMATRIX Hepatic stellate cells Kupffer cells
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Patent foramen ovale closure reduces recurrent stroke risk in cryptogenic stroke:A systematic review and metaanalysis of randomized controlled trials 被引量:9
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作者 Mahesh Anantha-Narayanan Dixitha Anugula Gladwin Das 《World Journal of Cardiology》 CAS 2018年第6期41-48,共8页
AIM To investigate if patent foramen ovale(PFO) closure device reduces the risk of recurrent stroke in patients with cryptogenic stroke.METHODS We searched five databases-Pub Med,EMBASE,Cochrane,CINAHL and Web-of-Scie... AIM To investigate if patent foramen ovale(PFO) closure device reduces the risk of recurrent stroke in patients with cryptogenic stroke.METHODS We searched five databases-Pub Med,EMBASE,Cochrane,CINAHL and Web-of-Science and clinicaltrials.gov from January 2000 to September 2017 for randomized trials comparing PFO closure to medical therapy in cryptogenic stroke.Heterogeneity was determined using Cochrane's Q statistics.Random effects model was used.RESULTS Five randomized controlled trials with 3440 patients were included in the analysis.Mean follow-up was 50 ± 20 mo.PFO closure was associated with a 41% reduction in incidence of recurrent strokes when compared to medical therapy alone in patients with cryptogenic stroke [risk ratio(RR): 0.59,95%CI: 0.40-0.87,P = 0.008].Atrial fibrillation was higher with device closure when compared to medical therapy alone(RR: 4.97,95%CI: 2.22-11.11,P < 0.001).There was no difference between the two groups with respect to all-cause mortality,major bleeding or adverse events.CONCLUSION PFO device closure in appropriately selected patients with moderate to severe right-to-left shunt and/or atrial septal aneurysm shows benefit with respect to recurrent strokes,particularly in younger patients.Further studies are essential to evaluate the impact of higher incidence of atrial fibrillation seen with the PFO closure device on long-term mortality and stroke rates. 展开更多
关键词 PATENT foramen ovale CRYPTOGENIC STROKE META-ANALYSIS
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Activation of canonical Wnt signaling pathway promotes proliferation and self-renewal of rat hepatic oval cell line WB-F344 in vitro 被引量:16
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作者 Ying Zhang Xin-Min Li Fu-Kui Zhang Bao-En Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第43期6673-6680,共8页
AIM: To investigate the effect of activation of canonical Wnt signaling pathway on the proliferation and differentiation of hepatic oval cells in vitro. METHODS: WB-F344 cells were treated with recombinant Wnt3a (2... AIM: To investigate the effect of activation of canonical Wnt signaling pathway on the proliferation and differentiation of hepatic oval cells in vitro. METHODS: WB-F344 cells were treated with recombinant Wnt3a (20, 40, 80, 160, 200 ng/mL) in serum-free medium for 24 h. Cell proliferation was measured by Brdu incorporation analysis; untreated WB-F344 cells were taken as controls. After treatment with Wnt3a (160 ng/mL) for 24 h, subcellular localization and protein expression of p-catenin in WB-F344 cells treated and untreated with Wnt3a were examined by immunofluorescence staining and Western blot analysis. CyclinD1 mRNA expression was determined by semi-quantitative reverse-transcript polymerase chain reaction (RT-PCR). The mRNA levels of some phenotypic markers (AFP, CK-19, ALB) and two hepatic nuclear factors (HNF-4, HIVF-6) were measured by RT-PCR. Expressions of CK-19 and AFP protein were detected by Western blot analysis. RESULTS: Wnt3a promoted proliferation of WB-F344 cells. Stimulation of WB-F344 cells with recombinant Wnt3a resulte^l in accumulation of the transcriptional activator β-catenin, together with its translocation into the nuclei, and up-regulated typical Wnt target gene CyclinD1. After 3 d of Wnt3a treatment in the absence of serum, WB-F344 cells retained their bipotential to express several specific phenotypic markers of hepatocytes and cholangiocytes, such as AFP and CK-19, following activation of the canonical Wnt signaling pathway. CONCLUSION: The canonical Wnt signaling pathway promotes proliferation and self-renewal of rat hepatic oval cells. 展开更多
关键词 Canonical Wnt signaling pathway oval cells Cell proliferation Self-renewal of cells
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The expression of c-kit and proliferating cell nuclear antigen in oval cells of rats with hepatocellular carcinoma 被引量:7
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作者 Chi-Hua Fang Wei Zhang +2 位作者 Xin-Yong Zhu Jia-Qing Gong Gang-Qing Zhang the Department of Hepatobiliary Surgery, Zhujiang Hospital, First Military Medical University, Guangzhou 510282, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2003年第4期537-544,共8页
OBJECTIVE: To study the relationship between oval cells and primary hepatocarcinoma and the expression of c-kit and proliferating cell nuclear antigen (PCNA) in oval cells of rats with hepatocellular carcinoma. METHOD... OBJECTIVE: To study the relationship between oval cells and primary hepatocarcinoma and the expression of c-kit and proliferating cell nuclear antigen (PCNA) in oval cells of rats with hepatocellular carcinoma. METHODS: A hundred and twenty clean SD rats were divided into three groups: normal group, cancer-induction group and intervention group. The normal group was fed with standard forage while the rest two groups were fed with 3'-methyl-2-methylamino-azobenzene (DAB) to induce carcinoma for 14 weeks and then fed with standard forage and water. Uscharidin was injected abdominally to the intervention group from the first week to the 14th week. All rats were killed and biopsy specimens were taken from the left and right liver lobes for immunohistochemical staining of c-kit and PCNA on the 2nd, 4th, 6th, 8th, 10th, 12th, 14th, 16th, 18th, 20th, 22nd, and 24th week. RESULTS: From the 2nd to 14th week after liver infection, c-kit positive cells, mainly oval cells were found in the portal area in the carcinoma-induction group and dotted positive pigmentations in liver lobules. In the 22nd week, a large number of cancerous nodes occurred and nuclei heteromorphi-m was apparent; the number of positive cell decreased but positive cells could be sparsely observed in cancerous nodes. In the 2nd week of the carcinoma-induction process, PCNA positive cells were oval cells in the portal area. In the 4th week, a lot of hepatic cells were positively stained, especially in the central vein area. In the 6th week, PCNA positive cells could be seen in the lobules of the liver. In the 8th week, the number of PCNA cells decreased comparatively. From the 10th to 14th week, oval cells in the portal area were still over-expressed. From the 16th to 24th week, a large number of cancerous nodes occurred and PCNA was over-expressed in some of them. In necrotic cancerous nodes, the para-cancerous PCNA positive cells were sparsely distributed and their number was less than that of PCNA positive cells of cancerous tissues. CONCLUSIONS: Hepatic stem cells originating from the terminal biliary plexus of the portal area are involved in the development of hepatocarcinoma because c-kit positive cells expressed in cancerous nodes, accompany the whole process of the development. In the middle inflammatory period of carcinoma-induction, the expression of PCNA in hepatic cells peaked, but the index decreased in the late inflammatory period and in the proliferated fibrosis stage. The expression of PCNA is a tortuous process, going up, down, then up again from normal tissues to cancerous tissues. Combined with pathological findings, PCNA can be considered as a warning index for carcinomatous cells. 展开更多
关键词 hepatocellular carcinoma oval cell proliferating cell unclear antigen C-KIT
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基于OVAL的安卓漏洞检测评估系统 被引量:2
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作者 万燕 赵希 王国林 《计算机科学》 CSCD 北大核心 2017年第4期79-81,共3页
传统漏洞检测工具检测时间长,占用大量系统资源,需要对系统进行模拟攻击,难以应对越来越复杂的安卓漏洞威胁。提出了一种"C/S"架构的、基于开放漏洞评估语言(OVAL)的安卓漏洞检测评估系统。这种架构将大部分评估工作放在控制... 传统漏洞检测工具检测时间长,占用大量系统资源,需要对系统进行模拟攻击,难以应对越来越复杂的安卓漏洞威胁。提出了一种"C/S"架构的、基于开放漏洞评估语言(OVAL)的安卓漏洞检测评估系统。这种架构将大部分评估工作放在控制台端执行,减少了对安卓系统性能的影响,其以OVAL作为漏洞评估标准,在保证评估高精度的同时也具有更好的开放性和可扩展性。 展开更多
关键词 漏洞检测 开放漏洞评估语言 安卓
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Distribution of oval cells and c-myc mRNA expression in mouse hepatocarcinogenesis 被引量:6
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作者 Chi-Hua Fang, Gang-Qing Zhang, Xin-Yong Zhu and Jia-Qing Gong Department of Hepatobiliary Surgery, Zhujiang Hos-pital of the First Military Medical University, Guangzhou 510282, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2004年第3期433-439,共7页
BACKGROUND: This study was designed to assess theroles of oval cells and c-myc mRNA in the process of hepa-tocarcinogenesis and to clarify the function of carcinogenec-myc in the development of hepatocellular carcinom... BACKGROUND: This study was designed to assess theroles of oval cells and c-myc mRNA in the process of hepa-tocarcinogenesis and to clarify the function of carcinogenec-myc in the development of hepatocellular carcinoma( HCC) and the mechanism of inhibitory function of uscha-ridin on HCC in mouse hepatocarcinogenesis.METHODS: A total of 120 clean SD mice were divided intonormal group, cancer induction group, and interventiongroup. The normal group was fed with standard foragewhile the rest two groups were given p-dimethylaminoazo-benzene (DAB) to induce cancer. Thirteen weeks after in-duction of cancer, the two groups were fed with standardforage and water. Once the pattern was set up, the inter-vention group was given uscharidin injection into the ab-dominal cavity from the first week to the 14th week. Onthe 2nd, 4th, 6th, 8th, 10th, 12th, 14th, 16th, 18th, 20th,22nd, and 24th week, all mice were killed and biopsiedfrom the liver lobe for pathological analysis. At the sametime, the number of tumor nodes was counted and the ex-pression of c-myc mRNA was tested by RT-PCR.RESULTS: Since the 2nd week after cancer induction, pro-liferated oval cells could be seen in the portal area. Initially,the oval cells appeared in the cortical layer of the portalarea, then proliferated gradually and immigrated into theliver parenchyma. In the period of fibrosis after liver proli-feration, proliferated heaps of oval cells were noted in bothportal and peripheral areas. In the period of carcinomatouschange, oval cells could be seen both outside and inside ofcancer nodes, but most of them were distributed outside.The c-myc gene was expressed negatively in the liver tissueof mice. The quantity of the expression began to increaseat the time of infection of the liver and tended to increasewith the degree of hepatic injury. In the period of cancera-tion, the expression level of c-myc mRNA increased gra-dually. The intervention of uscharidin could not inhibit butdelay the increase of the expression of c-myc mRNA.CONCLUSION: Oval cells are closely related to hepatocar-cinoma cells, which play an important role in the occur-rence and development of hepatocarcinogenesis. Uschari-din can inhibit the occurrence of hepatocarcinogenesis orlocal spreading at the early stage of cancer induction byDAB, but it cannot inhibit the expression of c-myc. 展开更多
关键词 oval cell hepatocellular carcinoma c-myc mRNA uscharidin
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Intrahepatic transplantation of hepatic oval cells for fulminant hepatic failure in rats 被引量:7
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作者 Chen-Xuan Wu,Qi Zou,Zheng-Yan Zhu,Ying-Tang Gao,Yi-Jun Wang,Department of Hepatobiliary,The Third Center of Affiliated Hospital of Tianjin Medical University Key Laboratory of Artificial Cells of Tianjin,Tianjin 300170,China Author contributions:Wang YJ,Wu CH and Zou Q designed the research +2 位作者 Zou Q,Zhu ZY,Gao YT performed the research Zou Q analyzed the data Wang YJ and Wu CX wrote the paper.Supported by Tianjin Science Committee,Grant No.05SYSYJC02600 and Tianjin Health Bureau,Grant No.05KYR01 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第12期1506-1511,共6页
AIM: To evaluate the effect of intrahepatic transplantation of hepatic oval cells (HOC) on fulminant hepatic failure (FHF) in rats.METHODS: HOC obtained from rats were labeled with green fluocescent protein (GF... AIM: To evaluate the effect of intrahepatic transplantation of hepatic oval cells (HOC) on fulminant hepatic failure (FHF) in rats.METHODS: HOC obtained from rats were labeled with green fluocescent protein (GFP) or 5, 6- carboxyfluorescein diacetate succinmidyl ester (CFDASE). Cell fluorescence was observed under fluorescent microscope at 6, 24, 48 and 72 h after labeling. CFDA- SE labeled HOC (5 × 10^6 cells each rat) were injected into livers of rats with FHF induced by D-galactosamine. Serum albumin (ALB), alanine aminotransferase (ALT), aspartate aminotransferase (AST) and total bilirubin (TBil) levels were measured at different time points. Liver function of rats was examined on days 3, 7, 14 and 21 after HOC transplantation.RESULTS: The positive rate of GFP and CFDA-SE labeled HOC was 10% and 90%, respectively, with no significant change in cell viabilities. The survival rate was higher in HOC transplantation group than in control group, especially 48 (9/15 vs 6/15) and 72 h (9/15 vs 4/15) after HOC transplantation. The serum ALT, AST and TBil levels were decreased while the serum AIb level was increased after HOC transplantation. Fluorescence became faded and diffused in liver tissues, suggesting that proliferation and differentiation occur in transplanted HOC.CONCLUSION: CFDA-SE is superior to GFP in labeling HOC, although fluorescence intensity is decreased progressively with cell division. HOC transplantation can improve the liver function and increase the survival rate of recipients. 展开更多
关键词 LIVER Stem cells Hepatic oval cells Fluorescence labeling TRANSPLANTATION Fulminanthepatic failure
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Ultrastructure of oval cells in children with chronic hepatitis B,with special emphasis on the stage of liver fibrosis:The first pediatric study 被引量:6
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作者 Maria Elzbieta Sobaniec-Lotowska Joanna Maria Lotowska Dariusz Marek Lebensztejn 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第21期2918-2922,共5页
AIM:To investigate the ultrastructure of oval cells in children with chronic hepatitis B,with special emphasis on their location in areas of collagen fibroplasia. METHODS:Morphological investigations were conducted on... AIM:To investigate the ultrastructure of oval cells in children with chronic hepatitis B,with special emphasis on their location in areas of collagen fibroplasia. METHODS:Morphological investigations were conducted on biopsy material obtained from 40 children,aged 3-16 years with chronic hepatitis B. The stage of fibrosis was assessed histologically using the arbitrary semiquantitative numerical scoring system proposed by Ishak et al. The material for ultrastructural investigation was fixed in glutaraldehyde and paraformaldehyde and processed for transmission-electron microscopic analysis. RESULTS:Ultrastructural examination of biopsy specimens obtained from children with chronic hepatitis B showed the presence of two types of oval cells,the hepatic progenitor cells and intermediate hepatic-like cells. These cells were present in the parenchyma and were seen most commonly in areas of intense periportal fibrosis (at least stage 2 according to Ishak et al) and in the vicinity of the limiting plate of the lobule. The activated nonparenchymal hepatic cells,i.e. transformed hepatic stellate cells and Kupffer cells were seen in close proximity to the intermediate hepatic-like cells. CONCLUSION:We found a distinct relationship between the prevalence of oval cells (hepatic progenitor cells and intermediate hepatocyte-like cells) and fibrosis stage in pediatric patients with chronic hepatitis B. 展开更多
关键词 Pediatric patients oval cells Ultrastructural study Chronic hepatitis B Liver biopsy FIBROSIS
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