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101.
目的 检测MiR-150在鼻咽癌侧群(SP)细胞中的表达,并探讨其是否通过调控靶基因Nanog促进鼻咽癌侧群细胞的增殖与侵袭。 方法 采用SYBR Green 实时定量荧光聚合酶链式反应(qRT-PCR)法检测MiR-150及Nanog在鼻咽癌侧群细胞和非侧群(NSP)细胞中的表达情况;并通过瞬时转染miR-150 inhibitor 至SP细胞、miR-150 mimic至NSP细胞中,western blotting检测Nanog的表达情况;进一步通过CCK-8实验、Transwall实验检测鼻咽癌侧群细胞增殖、侵袭能力的变化,数据处理采用两独立样本t检验。 结果 qRT-PCR检测结果表明,MiR-150在SP细胞(0.99±0.05)较NSP细胞(0.59±0.02)中表达水平升高(t=8.06, P<0.000 1),Nanog在鼻咽癌SP细胞(0.99±0.47)较NSP 细胞(0.49±0.05)表达升高(t=7.5, P<0.000 1);SP细胞转染MiR-150 inhibitor(0.46±0.03)较对照组(1.01±0.07)Nanog表达下调(t=6.85, P=0.000 5)、CCK-8实验示增殖受抑制、Transwell侵袭实验示侵袭能力减弱(114.40±5.14 vs 57.30±4.29, t=8.5, P<0.000 1);NSP细胞转染MiR-150 mimic(1.01±0.06)组较对照组(0.48±0.04)Nanog表达上调(t=6.16, P=0.000 8),增殖及侵袭能力增强。 结论 鼻咽癌SP细胞中MiR-150与Nanog呈高表达,MiR-150可通过调控靶基因Nanog促进鼻咽癌侧群细胞的增殖与侵袭。 相似文献
102.
活血定眩胶囊对CSA模型大鼠椎动脉血流量及血浆PAI、t-PA水平的影响 总被引:1,自引:0,他引:1
目的 探究活血定眩胶囊对椎动脉型颈椎病(cervical spondylosis of vertebral artery type,CSA)模型大鼠椎动脉血流量以及血浆中组织型纤溶酶原激活物(tissue type plasminogen activator,t-PA)和纤溶酶原激活物抑制物(plasminogen activator inhibitor ,PAI)的影响。方法 将90只健康雄性Wistar大鼠随机分为对照组、模型组及治疗组3组,每组30只。对照组不做处理,模型组及治疗组采用复合造模法制造CSA模型大鼠。治疗组在造模4周后按照人鼠折算系数开始给予活血定眩胶囊药物干预6周。每组分别在造模前、干预前及干预后3个不同时间点检测椎动脉血流量及血浆PAI、t-PA含量。结果 干预前,模型组与治疗组的椎动脉血流量均低于对照组(P<0.05);干预后,治疗组高于对照组(P<0.05)。与本组造模前分别比较,模型组及治疗组干预前血清PAI、t-PA含量均升高(P<0.01)。与对照组同期比较,模型组及治疗组干预前PAI、t-PA含量升高(P<0.01)。与本组干预前进行比较,模型组造模后血清PAI、t-PA含量升高(P<0.01),治疗组干预后血清PAI、t-PA含量降低(P<0.01)。与模型组同期比较,治疗组干预后血清PAI、t-PA含量降低(P<0.01)。结论 活血定眩胶囊可提高椎动脉血流量,降低血清PAI、t-PA含量。 相似文献
103.
104.
J. M. SAID R. TSUI A. J. BORG J. R. HIGGINS E. K. MOSES S. P. WALKER P. T. MONAGLE S. P. BRENNECKE 《Journal of thrombosis and haemostasis》2012,10(5):881-886
Summary. Background: Plasminogen activator inhibitor type 1 (PAI‐1) is an important regulator of fibrinolysis. A common deletion polymorphism that results in a sequence of 4G instead of 5G in the promoter region of the gene is associated with a small increase in the risk of venous thromboembolism. Its potential association with adverse pregnancy events remains controversial. Objective: We aimed to assess the impact of the 4G PAI‐1 polymorphism on pregnancy outcomes in women who had no prior history of adverse pregnancy outcomes or personal or family history of venous thromboembolism. Patients/methods: This study represents a secondary investigation of a prior prospective cohort study investigating the association between inherited thrombophilias and adverse pregnancy events in Australian women. Healthy nulliparous women were recruited to this study prior to 22 weeks gestation. Genotyping for the 4G/5G PAI‐1 gene was performed using Taqman assays in an ABI prism 7700 Sequencer several years after the pregnancy was completed. Pregnancy outcome data were extracted from the medical record. The primary outcome was a composite comprising development of severe pre‐eclampsia, fetal growth restriction, major placental abruption, stillbirth or neonatal death. Results: Pregnancy outcome data were available in 1733 women who were successfully genotyped for this polymorphism. The primary composite outcome was experienced by 139 women (8% of the cohort). Four hundred and fifty‐nine women (26.5%) were homozygous for the 4G deletion polymorphism, while 890 (51.4%) were heterozygous. Neither homozygosity nor heterozygosity for the PAI‐1 4G polymorphism was associated with the primary composite outcome (homozygous OR = 1.30, 95% CI = 0.81–2.09, P = 0.28, heterozygous OR = 0.84, 95% CI = 0.53–1.31, P = 0.44) or with the individual pregnancy complications. Conclusion: The PAI‐1 4G polymorphism is not associated with an increase in the risk of serious adverse pregnancy events in asymptomatic nulliparous women. 相似文献
105.
Seltz LB Bakel LA Tiehen J Gao D Cadnapaphornchai MA Lum G Ford D 《Thrombosis research》2012,130(3):e26-e30
Introduction
Hemolytic uremic syndrome is a thrombotic microangiopathy. Clopidogrel, a recently developed platelet aggregation inhibitor, has not been previously reported as a treatment for this illness. Our study's objective was to explore the efficacy and safety of clopidogrel in children with diarrhea associated hemolytic uremic syndrome.Materials and Methods
We performed a retrospective chart review of all children (≤ 18 years) hospitalized with diarrhea associated hemolytic uremic syndrome. Outcomes in clopidogrel treated children were described. In subgroup analysis, outcomes were compared to those untreated with platelet aggregation inhibitors.Results
Of 72 children with diarrhea associated hemolytic uremic syndrome, 88% were treated with platelet aggregation inhibitors (clopidogrel 56%, sulfinpyrazone 19%, dipyridamole 13%). The median age of clopidogrel treated children was 5 years; 40% were male. Initial median hemoglobin, platelet count, and serum creatinine were 10.1 g/dL, 53 × 103/μL, and 2.3 mg/dL respectively. Clopidogrel (median dose 1 mg/kg/d) was given for a median of 4 days (range 1-15). Other therapies included erythropoietin (98%), red blood cell transfusions (80%), diuretics (58%), anti-hypertensive agents (45%), and dialysis (33%). The median hospital length of stay was 9 days (range 3-26). Three children had bleeding complications (epistaxis/hematemesis). The risk of chronic kidney disease was 5% and death 2.5%. In subgroup analysis, median duration of dialysis was 11 days in thirteen clopidogrel treated children compared to 21 days in five untreated patients (P = 0.04).Conclusions
Children with diarrhea associated hemolytic uremic syndrome treated with clopidogrel have outcomes comparable to untreated patients. Bleeding complications may occur. 相似文献106.
Background
Orthopedic hip and knee surgeries are followed by a hypercoagulable state. Heparanase is implicated in inflammation, coagulation activation and angiogenesis. Recently, heparanase was shown to directly interact with tissue factor (TF) and to enhance the generation of factor Xa (Nadir et al., Haematologica, 2010). In addition, an assay assessing heparanase procoagulant activity has been lately developed (Nadir et al., Thromb Res, 2011). In the present study heparanase level and procoagulant activity in patients undergoing orthopedic surgery were assessed.Methods
The study group included 50 orthopedic patients. 31 patients underwent hip surgery and 19 had knee operation. 15 individuals suffered from traumatic hip fractures and 35 had osteoarthrosis of hip or knee joints. All patients received prophylactic dose of enoxaparin starting 6-8 hours post operation and lasting for 5 weeks. Plasma samples were drawn preoperatively and at 1 hour, 1 week and 1 month post operation. Samples were tested for heparanase levels by ELISA and TF/heparanase complex activity, TF activity, heparanase procoagulant activity, factor Xa and thrombin levels using chromogenic substrates.Results
Heparanase levels were significantly higher 1 hour and 1 week post operatively compared to preoperative levels (p < 0.05, p < 0.005, respectively). The most dramatic changes were observed in heparanase procoagulant activity reaching a 2 fold increase 1 week postoperatively and 1.7 fold increase 1 month after surgery (p < 0.0001, p < 0.0001, respectively). Levels of factor Xa and thrombin did not significantly change.Conclusions
Heparanase is involved in coagulation activation of orthopedic surgery patients. Heparanase procoagulant activity is highest 1 week postoperatively and remains high 1 month after operation. Considering extending prophylactic anticoagulant therapy or evaluating heparanase procoagulant activity may potentially prevent late thrombotic events. 相似文献107.
P. M. MANNUCCI R. ASSELTA S. DUGA I. GUELLA M. SPREAFICO L. LOTTA P. A. MERLINI F. PEYVANDI S. KATHIRESAN D. ARDISSINO 《Journal of thrombosis and haemostasis》2010,8(10):2116-2121
See also Tosetto A. Thrombophilic mutations and cardiovascular disease: the case is still open. This issue, pp 2113–5. Summary. Aims: Gain‐of‐function variants of genes encoding coagulation factor V (F5 G1691A) and prothrombin (F2 G20210A) cause hypercoagulability and are established risk factors for venous thrombosis. A meta‐analysis of 66 155 cases and 91 307 controls found that either polymorphism is associated with a moderately increased risk of coronary artery disease (CAD). Because genetic factors play a particularly important role when acute myocardial infarction (AMI) occurs in the young, we chose to replicate these results by investigating, in the frame of a case‐control study, a large cohort of Italian patients who had AMI before the age of 45 years. Methods and Results: In 1880 patients with AMI (1680 men and 210 women) and an equal number of controls, the minor A allele of F5 G1691A (2.6% frequency in cases and 1.7% in controls) was associated with an increased risk of AMI, the association remaining significant after adjustment for traditional risk factors (OR, 1.66; 95% CI, 1.15–2.38; P = 0.006). The positive association with AMI for the minor A allele of F2 G20210A (2.5% frequency in cases and 1.9% in controls) did not reach statistical significance (OR, 1.32; 95% CI, 0.96–1.80; P = 0.159). Conclusions: In a large cohort of young AMI patients the gain‐of‐function variant F5 G1691A was associated with an increased risk of AMI. The findings on the variant F2 G20210A confirmed the previously reported results, but the association was statistically not significant. These data suggest that a number of young patients with AMI carry gene variants associated with a procoagulant phenotype. 相似文献
108.
脑络通对脑缺血损伤防治作用的实验观察 总被引:23,自引:1,他引:22
目的探讨脑络通防治缺血性脑损伤的作用机制。方法采用多因素病证结合的气虚血瘀证脑缺血动物模型。观察脑络通对血浆t-PA(tissue
plasminogen activator组织型纤溶酶原激活物)、PAI(plasminogen activator inhibitor组织型纤溶酶原激活物抑制物)及血清IL-1β(interleukin-1β白细胞介素-1β)、IL-6(interleukin-6白细胞介素-6)含量的影响。结果与缺血模型组比较,脑络通可显著提高血浆t-PA活性(p<0.01),降低PAI活性(p<0.01),降低血清IL-1β水平(p<0.01)及IL-6水平(p<0.05),且优于药物对照组。结论在脑缺血急性期,脑络通可通过改善血浆纤维蛋白溶解系统活性,调节炎性介质释放,从多个病理环节阻断缺血性脑损伤,为益气活血的中药复方制剂脑络通防治缺血性脑血管疾病提供了进一步的实验证据。 相似文献
109.
冠心病患者伴有幽门螺杆菌感染时的凝血与溶血系统改变 总被引:2,自引:0,他引:2
目的 研究冠心病患者伴有幽门螺杆菌感染时的凝血与溶血系统改变 ,探讨HP感染与冠心病的关系。方法 (1)选择HP阳性冠心病患者和HP阴性冠心病患者各 6 0例 ,测定凝血系统主要指标———纤维蛋白原 (Fb)和溶血系统指标———组织纤溶酶原激活物 (t PA)、纤溶酶原激活抑制剂 (PAI) ;(2 )对HP阳性冠心病患者治疗前后的上述指标进行测定。结果 (1)HP阳性冠心病组的Fb(3.5 8±0 .36 )g L高于对照组 (HP阴性冠心病组 ) (3.2 5± 0 .48)g L ,P <0 .0 5 ;t PA(0 .6 8± 0 .11)KIU L低于对照组(1.0 8± 0 .12 )KIU L ,P <0 .0 5 ;PAI(8.76± 1.19)KAU L低于对照组 (7.98± 1.2 5 )KAU L ,P <0 .0 5。 (2 )HP阳性冠心病组治疗前后上述指标明显改变 ,Fb(3.0 4± 0 .2 4)g L ,P <0 .0 5 ;t PA(0 .85± 0 .17)KIU L ,P<0 .0 5 ;PAI(7.98± 1.2 5 )KAU L ,P <0 .0 5。结论 冠心病患者伴有幽门螺杆菌感染时可引起凝血和溶系统指标改变 ,增加冠心病急性事件的发生。 相似文献
110.
冷光源光化学诱导局灶性脑梗塞及血管损伤半暗带大鼠模型 总被引:16,自引:2,他引:14
目的 建立可同时观察局灶性梗塞区及周边血管损伤半暗带的大鼠脑缺血动物模型,并可进行局部脑组织血流、t-PA、PAI、NO、ET等指标变化的监测,以期为脑缺血血管因素变化规律的研究及治疗药物的筛选提供可靠实用的工具。方法 利用已建立的光化学诱导血栓形成的原理,短时间内造成大鼠脑皮质大脑中动脉供血区的完全性局灶性梗塞,观察梗塞面积、血管损伤半暗带面积及程度、组织病理、局部脑组织血流、t-PSA、PAI、NO、ET等指标的时相变化。结果 实验数据显示,在局灶性梗塞形成后,梗塞灶、周边血管损伤半暗带、脑组织血流、纤溶、凝血各指标,模型动物与对照组比较表现出不同的时相变化趋势。结论 该模型观察指标较全面,可为脑梗塞后血管损伤保护及溶栓治疗提供实用性工具。 相似文献