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101.
目的:缝隙连接蛋白43对维持心肌细胞的连接通讯功能、电信号传导和正常的节律性收缩起重要作用,其表达和分布的异常是多种室性心律失常的解剖学基础,建立小型猪急性心肌梗死模型.观察自体骨髓间充质干细胞移植后室性心动过速的发生及心肌缝隙连接蛋白43的表达方法:实验于2006-01/2007-01在河北省人民医院导管室完成。①材料:选取8~12月龄小型猪22头,由河北医科大学实验动物中心提供,体质量20~30 kg,随机数字表法分为细胞移植组12头、模型对照组10头.实验过程中对动物的处置符合动物伦理学际准②实验方法:无菌条件下抽取猪双侧股骨骨髓20 mL,percoll法 贴壁法分离培养骨髓间充质干细胞,待细胞生长达75%融合时用胰酶消化传代。将传至第2代细胞加入终浓度为10μmol/L的5-氮胞苷进行诱导,用胶体金标记12 h后继续培养20 d用于移植:两组小型猪均采用球囊堵闭法建立急性心肌梗死模型.心电图监测示相关至少2个导联ST段抬高大于0.2 mV、术后血肌钙蛋白和肌酸磷酸激酶同工酶升高超过正常的两倍为建模成功标准:细胞移植组于造模成功后经OTW球囊于第一对角支远端1 cm处再次阻断血流,注入经胶体金标记的10×10~7个骨髓间充质干细胞。③实验评估:于细胞移植后2 h及4周行电生理程序刺激.观察室性心动过速的发生情况。末次电生理检查后、采用免疫组化染色法检测心肌缝隙连接蛋白43的表达.计算其积分吸光度值。结果:①模型建立指标检测:与术前比较.造模后所有小型猪血肌钙蛋白含量和肌酸磷酸激酶同工酶活性均增高,峰值浓度分别为(21.3±3.6)μg/L和(178.3×41.4)IU/L,术中心电图ST段平均抬高(10.67±1.43)mm.证明急性心肌梗死模型成功建立。②骨髓间充质干细胞移植后室性心动过速的发生情况:与模型对照组诱发出室性心动过速的动物数量比较,术后2 h细胞移植组无明显变化(X~2=0.201,P=0.650),术后4周细胞移植组明显降低(X~2=4.455.P=0.035)。②骨髓间充质干细胞移植后梗死心肌缝隙连接蛋白43的表达:术后4周移植到梗死心肌的骨髓间充质干细胞与宿主心肌生长为一体,移植部位颜色变黑,苏木精-伊红染色示移植细胞的胞浆呈紫红色。细胞移植组心肌梗死区缝隙连接蛋白43积分吸光度值明显高于模型对照组(t=16,82.P=0.00),细胞移植组中未发生室性心动过速小型猪的梗死心肌缝隙连接蛋白43的表达明显高于发生室性心动过速小型猪(t=5.06,P=0.00)。结论:自体骨髓间充质干细胞移植可促进急性心肌梗死猪心肌缝隙连接蛋白43的表达,其表达程度可能与急性心肌梗死室性心动过速的发生有关。 相似文献
102.
PGE1 accelerates thrombolysis by tissue plasminogen activator 总被引:14,自引:0,他引:14
Platelets are an active element in the generation of thrombus and may influence rates of thrombolysis during the administration of plasminogen activators. To assess the potential importance of platelet aggregation in the thrombolytic response to plasminogen activators, we measured rates of thrombolysis induced by tissue plasminogen activator in the presence and absence of a coinfusion of prostaglandin E1 in a rabbit jugular vein model of thrombosis. Rates of lysis were quantified by measuring the half-time for lysis of the thrombus. At all concentrations of tissue plasminogen activator used, prostaglandin E1 markedly reduced the half-time for clot lysis and enhanced somewhat the overall extent of thrombolysis, without affecting significantly either the degree of fibrinogen depletion or the animals' mean arterial pressures. These effects on thrombolytic efficacy were accompanied by ex vivo evidence of platelet inhibition. These data suggest that the antiplatelet prostaglandin E1 may be a very useful adjunctive agent in thrombolytic therapy primarily by virtue of the significant improvement in the rate of thrombolysis that its use affords. 相似文献
103.
SR Kulkarni MS Gohel RA Bulbulia MR Whyman KR Poskitt 《Annals of the Royal College of Surgeons of England》2009,91(3):210-213
INTRODUCTION
Early carotid endarterectomy (CEA) in symptomatic patients may prevent repeat cerebral events. This study investigates the relationship between waiting time for CEA and the incidence of repeat cerebral events prior to surgery in symptomatic patients.PATIENTS AND METHODS
A prospective database of consecutive patients undergoing CEA between January 2002 and December 2006 was reviewed. Repeat event rates prior to surgery were calculated using Kaplan–Meier analysis and predictive factors identified using Cox regression analysis.RESULTS
A total of 118 patients underwent CEA for non-disabling stroke, TIA and amaurosis fugax. Repeat cerebral events occurred in 34 of 118 (29%) patients at a median 51 days (range, 2–360 days) after the first event. The estimated risk of repeat events was 2% at 7 days and 9% at 1 month after first event (Kaplan–Meier survival analysis). Age (HR 1.059; 95% CI 1.014–1.106; P = 0.009] was identified as a predictor of repeat events. Patients underwent surgery at median 97 days (range, 7–621 days) after the first event. Eleven of 60 (18%) patients waiting ≤?97 days for surgery and 23 of 58 (40%) patients waiting >?97 days had repeat events. (P = 0.011, chi-squared test).CONCLUSIONS
Delays in surgery should be reduced in order to minimise repeat cerebral events in patients with symptomatic carotid stenosis, particularly in the elderly population. 相似文献104.
India has a high prevalence of diabetes mellitus and the numbers are increasing at an alarming rate. In India alone, diabetes is expected to increase from 40.6 million in 2006 to 79.4 million by 2030. Studies have shown that the prevalence of diabetes in urban Indian adults is about 12.1%, the onset of which is about a decade earlier than their western counterparts and the prevalence of Type 2 diabetes is 4–6 times higher in urban than in rural areas. The risk factors peculiar for developing diabetes among Indians include high familial aggregation, central obesity, insulin resistance and life style changes due to urbanization. Screening for gestational diabetes and impaired glucose tolerance among pregnant women provides a scope for primary prevention of the disease in mothers as well as in their children. The problems of obesity and impaired glucose tolerance (IGT) (important predisposing factors) are not confined to adults alone but children are also increasingly getting affected. Most long standing macro and micro vascular complications are also more common among Indian diabetics as compared to other races and ethnic groups. A strong familial clustering of diabetic nephropathy among Indian Type 2 diabetics has also been noted. Clustering of cardiovascular risk factor like Syndrome X is common among urban Indians. The rising incidence of diabetes and its complications are going to pose a grave health care burden on our country. Timely effective interventions/measures and screening tests for complications at the time of diagnosis becomes imperative not only for early detection, but also to prevent progression to end stage disease. Screening for gestational diabetes among pregnant women would also go a long way in primary prevention of the disease. Life style changes/interventions and drugs like rosiglitazone are the current strategies that can prevent and/or delay the onset of diabetes. Simple interventional strategies like “Eat less, Eat on time and Walk more” can go a long way in preventing these chronic disorders among present as well as in the future generations. 相似文献
105.
Background
Disorders of visual acuity are known to affect the learning abilities of school children. Various authors have reported varying prevalence in India and abroad.Methods
A rapid, community based survey was conducted to assess the prevalence of disorders of visual acuity among adolescent school children in three schools in Pune Cantonment. A sample of 236 children studying in six sections were examined after random selection by a two stage sampling technique ensuring representation to each of the classes. Visual acuity was assessed for all the children available in the selected section on the date of survey. A questionnaire based study of the knowledge and attitude of the parents of the 50 affected children was also conducted.Result
50 children (25 males and 25 females) were found to have errors of refraction, resulting in prevalence rate of 21.19% with confidence intervals of 15.97% to 26.40%.Conclusion
The study highlights significantly high prevalence of uncorrected errors of visual acuity among adolescent school children as well as the need for instituting IEC activities aimed at improving the general lack of appreciation of the seriousness of the problem by the parents and consequent neglect of urgent corrective measures.Key Words: Visual defects, Adolescent school children 相似文献106.
107.
Triblock copolymer coated iron oxide nanoparticle conjugate for tumor integrin targeting 总被引:1,自引:0,他引:1
Kai Chen Jin Xie Hengyi Xu Deepak Behera Mark H. Michalski Sandip Biswal Andrew Wang Xiaoyuan Chen 《Biomaterials》2009,30(36):6912-6919
A key challenge in developing nanoplatform-based molecular imaging is to achieve an optimal pharmacokinetic profile to allow sufficient targeting and to avoid rapid clearance by the reticuloendothelial system (RES). In the present study, iron oxide nanoparticles (IONPs) were coated with a PEGylated amphiphilic triblock copolymer, making them water soluble and function-extendable. These particles were then conjugated with a near-infrared fluorescent (NIRF) dye IRDye800 and cyclic Arginine-Glycine-Aspartic acid (RGD) containing peptide c(RGDyK) for integrin αvβ3 targeting. In vitro binding assays confirmed the integrin-specific association between the RGD-particle adducts and U87MG glioblastoma cells. Successful tumor homing in vivo was perceived in a subcutaneous U87MG glioblastoma xenograft model by both magnetic resonance imaging (MRI) and NIRF imaging. Ex vivo histopathological studies also revealed low particle accumulation in the liver, which was attributed to their compact hydrodynamic size and PEGylated coating. In conclusion, we have developed a novel RGD–IONP conjugate with excellent tumor integrin targeting efficiency and specificity as well as limited RES uptake for molecular MRI. 相似文献
108.
Guomiao Shen Digambar Behera Manpreet Bhalla Arthur Nadas Suman Laal 《Clinical and Vaccine Immunology : CVI》2009,16(1):49-54
Tuberculosis (TB) is a major cause of morbidity and mortality, especially in developing countries. Despite significant limitations, microscopy remains the cornerstone of the global TB control strategy. As the TB epidemic escalates, new diagnostic methods that are accurate and also economical and simple to manufacture and deploy are urgently needed. Although several promising antigens have been identified and evaluated in recent years, the reproducible production of high-quality recombinant mycobacterial proteins with minimal batch-to-batch variation is difficult, laborious, and expensive. To determine the feasibility of devising a synthetic peptide-based diagnostic test for TB, we have delineated the immunodominant epitopes of three candidate antigens, Ag85B, BfrB, and TrxC, that were previously identified to be immunogenic in TB patients. The results demonstrate that combinations of carefully selected synthetic peptides derived from highly immunogenic proteins can be the basis for devising an immunodiagnostic test for TB. 相似文献
109.
110.
A Parolia M Kundabala NN Rao† SR Acharya P Agrawal† M Mohan‡ M Thomas 《Australian dental journal》2010,55(1):59-64
Background: Permanent teeth pulp exposures have traditionally been treated with calcium hydroxide pulp capping. The aim of this study was to investigate the response of human pulp tissue which were mechanically exposed to a new material, Propolis and compare it with two existing and commonly used pulp capping agents (mineral trioxide aggregate and Dycal).
Methods: Thirty-six intact human premolars were mechanically exposed. Teeth were divided into six groups of 6 teeth each and were capped with Propolis, mineral trioxide aggregate and Dycal. Final restoration was done with posterior composite resin using light cured glass ionomer cement as a liner. The teeth were then extracted on the 15th or the 45th day and processed for histological evaluation.
Results: Differences in inflammatory response and dentine bridge formation of the exposed pulp to the three different materials were statistically calculated using chi-square test and were found to be non-significant. There was more pulp inflammation in teeth treated with Dycal than with Propolis and MTA on the 15th as well as on the 45th day. Propolis and MTA showed bridge formation in more teeth, and the bridges were in closer proximity to pulp capping material than teeth treated with Dycal on the 45th day.
Conclusions: The response of pulps to Propolis as a pulp capping agent was comparable to MTA and Dycal. 相似文献
Methods: Thirty-six intact human premolars were mechanically exposed. Teeth were divided into six groups of 6 teeth each and were capped with Propolis, mineral trioxide aggregate and Dycal. Final restoration was done with posterior composite resin using light cured glass ionomer cement as a liner. The teeth were then extracted on the 15th or the 45th day and processed for histological evaluation.
Results: Differences in inflammatory response and dentine bridge formation of the exposed pulp to the three different materials were statistically calculated using chi-square test and were found to be non-significant. There was more pulp inflammation in teeth treated with Dycal than with Propolis and MTA on the 15th as well as on the 45th day. Propolis and MTA showed bridge formation in more teeth, and the bridges were in closer proximity to pulp capping material than teeth treated with Dycal on the 45th day.
Conclusions: The response of pulps to Propolis as a pulp capping agent was comparable to MTA and Dycal. 相似文献