首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
局部黏着斑激酶(focal adhesion kinase,FAK)是一种存在于细胞质中的酪氨酸激酶,对胚胎的生长,肿瘤、心血管疾病的发病机制都有重要作用.FAK分布广泛,序列在多种物种中高度保守.序列和结构分析显示FAK包含4个明显的区域:①N端的FERM区域;②起催化作用的酪氨酸激酶中心区域;③C端黏着斑定位序列(FAT)区域;④脯氨酸富集区域(PR1、PR2和PR3),定位于催化作用点和FAT区域之间.FAK分子中含有6个可被酪氨酸激酶磷酸化的位点:Y397、Y407、Y576、Y577、Y861和Y925.  相似文献   

2.
目的 探讨Syntenin促进人脑胶质瘤细胞迁移的分子机制.方法 采用划痕实验和Western blot检测CHG-5、稳定表达人源性Syntenin的CHG-hS细胞在纤维连接蛋白(fibronectin,FN)和多聚赖氨酸(Poly-l-lysine,PL)两种基质表面迁移能力、FAK磷酸化位点及相关信号分子的变化情况;分别在P38MAPK特异性抑制剂SB239063和PI3K特异性抑制剂LY294002处理后,FN基质上CHG-5、CHG-hS细胞迁移能力和下游信号分子JNK和AKT磷酸化水平的改变.结果 细胞划痕实验结果显示,CHG-hS细胞在FN表面的运动能力显著高于CHG-5细胞(P<0.05);而在多聚赖氨酸包被的培养板上,CHG-hS细胞的运动能力与CHG-5组细胞表面无显著性差异(P>0.05).Western blot检测结果显示,FN作用下CHG-hS细胞中FAK Tyr397、FAK Tyr576、FAK Tyr925位点的磷酸化水平随时间延长而逐渐升高(P<0.05),而FAK FAK Tyr861位点的磷酸化水平没有变化(P>0.05);相关信号Src、JNK、AKT的磷酸化水平也随时间延长而升高(P<0.05).分别采用SB239063和LY294002处理后,伴随着p-JNK和p-AKT的磷酸化水平减弱,CHG-hS迁移能力下降.结论 Syntenin通过与p-Src结合,随后触发FAK Tyr397、FAK Tyr925、FAK Tyr576位点的磷酸化作用,最大程度的激活FAK并上调JNK、AKT等下游信号分子的磷酸化水平,最终通过Syntenin-Src/FAK/MAPK和Syntenin-Src/FAK/PI3K两条通路增强FN相关胶质瘤细胞的迁移能力.  相似文献   

3.
目的探讨Syntenin促进人脑胶质瘤细胞迁移的分子机制。方法采用划痕实验和Western blot检测CHG-5、稳定表达人源性Syntenin的CHG-hS细胞在纤维连接蛋白(fibronectin,FN)和多聚赖氨酸(Poly-l-lysine,PL)两种基质表面迁移能力、FAK磷酸化位点及相关信号分子的变化情况;分别在P38MAPK特异性抑制剂SB239063和PI3K特异性抑制剂LY294002处理后,FN基质上CHG-5、CHG-hS细胞迁移能力和下游信号分子JNK和AKT磷酸化水平的改变。结果细胞划痕实验结果显示,CHG-hS细胞在FN表面的运动能力显著高于CHG-5细胞(P<0.05);而在多聚赖氨酸包被的培养板上,CHG-hS细胞的运动能力与CHG-5组细胞表面无显著性差异(P>0.05)。Western blot检测结果显示,FN作用下CHG-hS细胞中FAK Tyr397、FAK Tyr576、FAK Tyr925位点的磷酸化水平随时间延长而逐渐升高(P<0.05),而FAK FAK Tyr861位点的磷酸化水平没有变化(P>0.05);相关信号Src、JNK、AKT的磷酸化水平也随时间延长而升高(P<0.05)。分别采用SB239063和LY294002处理后,伴随着p-JNK和p-AKT的磷酸化水平减弱,CHG-hS迁移能力下降。结论 Syntenin通过与p-Src结合,随后触发FAK Tyr397、FAK Tyr925、FAK Tyr576位点的磷酸化作用,最大程度的激活FAK并上调JNK、AKT等下游信号分子的磷酸化水平,最终通过Syntenin-Src/FAK/MAPK和Syntenin-Src/FAK/PI3K两条通路增强FN相关胶质瘤细胞的迁移能力。  相似文献   

4.
受体酪氨酸激酶(RTK)家族是一类具有内源性蛋白酪氨酸激酶(PTK)活性的单次跨膜受体,它们在调控与细胞增殖、分化等相关的信号转导通路中起关键作用。它与配体结合后引起二聚化或结构重排而使胞内区的酪氨酸(Tyr)被自磷酸化。Tyr的自磷酸化一方面可以激活胞内PTK区的活性,另一方面可以为下游的信号蛋白提供结合位点从而完成活化过程。本文对RTK家族成员的晶体结构及其活性调节机制的研究进行了综述,阐述了由配体诱导RTK活化的结构基础,并简要讨论了RTK抑制剂可能的作用靶点。  相似文献   

5.
pp60c-Src是一个相对分子质量为60 000的、416位点磷酸化后激活的Src蛋白,是非受体型酪氨酸激酶家族中研究最多的成员.目前大量研究显示,Src或其家族活性异常与癌症的发生发展密切相关,它们参与了肿瘤的黏附、迁移、浸润及血管形成等过程.  相似文献   

6.
目的观察脑缺血再灌注后海马Src家族酪氨酸蛋白激酶(Src family of protein tyrosine kinase,SrcPTKs)成员Src、Fyn激酶对NMDA受体(N-methyl-D-aspartate receptors,NMDAR,NR)NR2A亚基磷酸化水平的影响。方法采用Pulsinelli-Brierley四动脉阻断(four-vessel occlusion,4-VO)大鼠全脑缺血模型,缺血前连续3天脑室注射Src、Fyn反义寡核苷酸(antisense oligode oxynucletides,AS-ODNs)及错义寡核苷酸组(missenseoligodeoxynucletides,MS ODNs)后缺血15 min,用免疫沉淀和免疫印迹法检测NR2A亚基酪氨酸磷酸化水平的变化。结果Fyn反义寡核苷酸使脑缺血再灌注海马NR2A亚基磷酸化水平下降,而Src反义寡核苷酸对脑缺血/再灌注海马NR2A亚基磷酸化水平影响更加明显。结论脑缺血/再灌注过程中NMDA受体NR2A亚基的磷酸化主要是由Src激酶介导的。  相似文献   

7.
目的 探讨Src酪氨酸激酶抑制剂对表皮生长因子(EGF)诱导的肺腺癌细胞生长浸润的作用及其机制。方法 选用PC-9和A549细胞进行培养,分别给予不同浓度的Src酪氨酸激酶抑制剂和EGF,利用MTT比色法和Boyden-chamber法检测PC-9和A549细胞增殖及浸润情况,台盼蓝染色检测细胞活力,蛋白质印迹检验Src蛋白的表达和磷酸化及其下游信号磷酸化情况。结果 抑制Src酪氨酸激酶可以在不影响细胞活力的情况下抑制PC-9和A549细胞的增殖浸润,EGF可以增强EGF受体(EGFR)、Src、促丝裂原活化蛋白激酶(MAPK)及AKT的磷酸化,Src酪氨酸激酶抑制剂可以抑制这种磷酸化。结论 抑制Src酪氨酸激酶可以通过调节EGFR及其下游信号通路抑制肺腺癌细胞的增殖浸润。  相似文献   

8.
目的研究神经生长因子前体(precursor of nerve growth factor, proNGF)促进乳腺癌细胞侵袭的作用与埃兹蛋白(ezrin) 表达水平及其567位苏氨酸(Thr567)和477位酪氨酸(Tyr477)的磷酸化的相互关系。方法用梯度浓度的proNGF(0、2.5、5和 10 ng/mL)刺激人乳腺癌细胞系MDA-MB-231 和MCF-7,用Transwell 侵袭实验检测proNGF对MDA-MB-231 和MCF-7 侵袭 的影响;用免疫印迹法检测ezrin 蛋白的表达水平,ezrin Thr567 和ezrin Tyr477 磷酸化水平的变化;在MDA- MB-231 中转染 pEnter-His-ezrinY477F质粒(ezrin显性负突变质粒),研究ezrin Tyr477磷酸化在proNGF促进乳腺癌细胞侵袭中的作用。结果 proNGF 以浓度依赖的方式促进MDA-MB-231 和MCF-7 的侵袭(P<0.05);proNGF 以浓度依赖和时间依赖的方式显著升高 ezrin Tyr477磷酸化,而对ezrin蛋白的表达以及其Thr567磷酸化无明显影响;Src激酶特异抑制剂SKI-606显著抑制proNGF对 ezrin Tyr477磷酸化的促进作用;转染pEnter-His-ezrinY477F抑制proNGF对MDA-MB-231细胞ezrin Tyr477磷酸化和侵袭能 力的促进作用(P<0.05)。结论ezrin Tyr477磷酸化在proNGF促进乳腺癌细胞侵袭中起关键作用;proNGF通过激活Src激酶使 ezrin Tyr477发生磷酸化。  相似文献   

9.
目的揭示哇巴因诱导急性淋巴细胞白血病细胞株Jurkat增殖的信号传导途径.方法采用MTT、Western Blot等方法,观察哇巴因及不同激酶抑制剂对Jurkat细胞生长的影响,同时检测酪氨酸活化水平和丝裂原活化蛋白激酶MAPK(ERK1/2)的磷酸化程度.结果哇巴因促使Jurkat细胞膜酪氨酸磷酸化水平增高,并激活ERK1/2.激酶抑制剂PD98059,PP2,HerbimycinA和PP3均可阻断哇巴因诱导ERK1/2 的活化并抑制哇巴因诱导Jurkat细胞的增殖.结论哇巴因激活钠泵的信号传导功能,引起细胞膜酪氨酸磷酸化水平增高,MAPK(ERK1/2)信号途径级联样活化,从而导致Jurkat的增殖反应.Src激酶和EGFR参与了钠泵介导的信号传导.  相似文献   

10.
盘状结构域受体酪氨酸激酶1(DDR1)是新发现的一种受体酪氨酸激酶,可以与其配体——胶原蛋白特异性结合,而这种结合可导致位于胞内区的酪氨酸激酶缓慢而持续的磷酸化,这种磷酸化可参与细胞的增殖、分化、黏附、迁移以及炎症信号通路的活化,进而导致多种病理学的改变,如纤维化和恶性肿瘤的发生、发展。同时,DDR1还可参与多个脏器的炎症反应,如肝炎、肾炎、中枢神经系统炎症等。未来,需进一步研究DDR1是否参与其他脏器的炎症反应,力求全面反映DDR1在炎症中所发挥的作用。  相似文献   

11.
Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P < 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (>0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P <0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P < 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.  相似文献   

12.
Objective: To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods: SD rats served as both donors and recipients. 4℃ sodium lactate Ringer's was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava (IVC) inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results: Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion: This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment.  相似文献   

13.
Objective To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing.Methods Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years.Results After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teenagers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8±5.2 mmHg, P< 0.01; 12.2%± 12.0% vs. 2.5% ±4.4%, P< 0.001,respectively). There was a similar trend for diastolic blood pressure (8.4 ± 6.4 mmHg vs. 3.7 ± 6.4 mmHg, P = 0.052; 13.2% ±10.6 % vs. 6.8%± 10.1%, P = 0.053, respectively).Conclusions Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure.  相似文献   

14.
目的:评价使用安心颗粒对急诊经皮冠状动脉介入术(PPCI)术后生活质量的影响.方法:将160例接受PPCI的急性ST段抬高型心肌梗死患者随机分为安心颗粒组(术前顿服安心颗粒8.8g,术后安心颗粒4.4 g/次,每日2次)和对照组(仅接受基础药物治疗).所有患者均服用阿司匹林、氯吡格雷和阿托伐他汀.分别在入院时、出院前1d、出院后180 d时,应用心肌梗死多维度量表(MIDAS)、中文版SF-36评价量表对患者生活质量评分.并观察术后30 d以内的出血并发症、血小板减少症发生情况.结果:入院时和出院前1d,两组患者的心肌梗死MIDAS、SF-36量表评分比较无差异(P>0.05);出院后180 d时,与对照组比较,安心颗粒组MIDAS、SF-36评分明显减低(P<0.05);组内与入院时比较,两组出院前1d、出院后180 d时,MIDAS、SF-36评分均降低(P<0.05).两组患者在随访期间均无大量出血、少量出血、重度和极重度血小板减少症发生,安心颗粒组有4例、对照组有7例发生不明显出血(P>0.05).两组发生轻度血小板减少症的患者数比较无差异(P>0.05).结论:PPCI使用安心颗粒,能改善急性ST段抬高型心肌梗死患者的生活质量,且不增加出血风险.  相似文献   

15.
Objective:To investigate the influences of urapidil and nicardipine on rabbit sinus function,atrio-ventricular node function and hemodynamics.Methods:Thirty-two Angora's rabbits were selected and randomly divided into four groups.U1 group:urapidil 0.25 mg/kg;U2 group:urapidil 0.5 mg/kg;N1 group:nicardipine 10 μg/kg;N2 group:nicardipine 20 μg/kg.All these medicine were administrated within 30 seconds.Measurements were taken before and after the administration of urapidil or nicardipine for the following data:mean blood pressure(MAP),heart rate(HR),sino-atrial conduction time(SACT),maximal sinoatrial recovery time(SNRTmax)corrected sinus node recovery time(CSNRT),index of sinus node recovery time(SNRTI),Wenckebach A-V conduction frequency (WB),and P-R interval.Results:Significant MAP and HR changes were identified in all of the four groups before and after administration of both urapidil and nicardipine.No significant changes could be found in the rest of the parameters.Intergroup analysis showed that SACT and CSNRT of N1 and N2 groups were shorter than those of the U2 group(P<0.01);the MAP decreased(P<0.01)and the HR increased drastically(P<0.01).Conclusions:Neither urapidil(0.25 mg/kg,0.5 mg/kg)nor nicardipine(10μg/kg,20μg/kg)has any significant influence on rabbit sinus function or rabbit atrio-ventricular node function.Nicardipine could be a better choice than urapidil for parafunctional sinus node patients.  相似文献   

16.
Objective:To investigate the gene expression of osteoprotegerin(OPG) and osteoclast differentiation factor(ODF) in the bone tissue of patients with hip fracture due to osteoporosis. Methods:OPGmRNA and ODFmRNA in the bone tissue in 50 cases of osteoporosis sufferers(over 50 years old) with hip fracture(Observer Group) and 30 cases of hip facture sufferers with no osteoporosis(Control group) were analyzed with the Semi-Quantitative RT-PCR method. Results:The mRNA expressed of ODF, OPG were both high in the patients with hip fracture. In the control group, the expression of OPG mRNA was observed, while the expression of ODF mRNA was very slight. Conclusion:Aged patients contained all signals including OPG, ODF that are essential for inducing osteoclastogenesis and promoting bone resorption.  相似文献   

17.
Objective:To investigate the clinical features, pathological characteristics and immunophenotype of solid-pseudopapillary tumor of the pancreas(SPTP). Methods:Nine surgically treated cases of SPTP were retrospectively reviewed. Hematoxylin and Eosin(HE) staining and immunohistochemical staining were used to analyze all cases, and the general clinical data was collected. Results:Six patients were asymptomatic except for a palpable mass. Two patients complained of vague-epigastric pain. One patient appeared jaundice. The tumor was encapsulated and solid tissues alternately with cystic tissues. Histologically, the histological structure of solid portion was pseudopapillary with a fibrovascular core. Tumor cells were uniform and medium-sized which were arranged in sheets ets or nests or pseudopapillary patterns. Immunohistochemical studies demonstrated that SPTP proved positive in vimentin(9/9 cases), AAT(9/9 cases), NSE(9/9 cases), ACT(7/9 cases), CK20(2/9 cases), CgA(1/9 cases), S-100(3/gcases), PR(4/gcases), Syn(3/9 cases) and CD56(5/9cases), negative in CEA and ER. Conclusion:SPTP is a tumor predominantly occurring in young women frequently without special symptoms. This tumor has various characteristical histological patterns with different immunophenotype.  相似文献   

18.
Objective:To probe into the influence of changes of ovarian hormones on the pathogenesis of the specific sub-type premenstrual syndrome(PMS)and reveal partial microcosmic mechanisms of adverse flow of liver-qi.Methods:Estradiol(E2)and progesterone(P)levels in serum were determined at different phases of menstrual cycle by radioimmunoassay.Results:In the group of PMS with adverse flow of liver-qi.the secretive peak value Of E2 and P at the follicular phase significantly decreased,and the secretive peak value at the luteal phase did not come into being.Conclusions:Low E2 and P secretive peak at the follicular phase and absence of secretive peak at the luteal phase is one of the microcosmic mechanisms of PMS with adverse flow of liver-qi.One of the pathophysiologic mechanisms of specific sub-type PMS is probably the continuous low level of E2and P.  相似文献   

19.
Real-time three-dimensional echocardiography (RT3DE)is a new ultrasound technique that enables dynamic threedimensional visualization and quantification of the heart in real time. Investigation of feasibility and methodology of RT3DE in determining left ventricular (LV) and right ventricular (RV) volumes, RT3DE was performed in 35 normal adults using Philips SONOS 7500 system with a 2-4 MHz matrix array transducer. The 60°×60° "pyramid" volume database was obtained and analyzed on a TomTec echo workstation. Both LV and RV volumes were calculated with four 3DE methods (i.e. apical 2, 4, 8, and 16-plane) through manually tracing ventricular endocardial borders in end diastole and end systole. Stroke volumes were then calculated. LV volume was also measured by 2DE Simpson's rule using GE VIVID 7 ultrasound machine.  相似文献   

20.
Increasing maternal age is the only etiological factor unequivocally linked to Down's syndrome in humans. The occurrence rate of newborns with Down's syndrome is about 1/220 in women over 35 years old. However, the occurrence rate in embryos fertilized in vitro, of the elder woman is unclear. Using FISH we screened the number of chromosome 21 in preimplanted embryos of 5 elderly women (average age, 38.4 years) to study the feasibility and necessity of screening trisomy 21 in embryos in patients over 35 years old at the in vitro fertilization (IVF) center.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号