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41.
42.
目的: 研究ATP竞争性糖原合成酶激酶3(GSK-3)抑制剂6-溴靛玉红-3'-肟(BIO)作用于食管鳞癌细胞后, 对ATP结合盒(ABC)转运蛋白——P-糖蛋白(P-gp)和多药耐药相关蛋白2(MRP2)、凋亡抑制蛋白Bcl-2以及β-catenin表达的影响,探讨它们表达的相互关系,以及对细胞内游离ATP水平和P-gp、MRP2转运功能的影响,进而初步探讨GSK-3抑制剂对食管鳞癌细胞多药耐药的影响。方法: BIO作用于食管鳞癌EC-109细胞后,运用免疫荧光细胞化学法、流式细胞术以及ATP检测试剂盒分别检测细胞内 MRP2、P-gp、β-catenin和Bcl-2表达的改变、ABC转运蛋白的转运功能以及细胞内游离ATP水平的改变。结果: BIO作用食管鳞癌EC-109细胞后,加药组与对照组相比,β-catenin和Bcl-2在胞浆中的表达增强,并且β-catenin出现胞核内累积,MRP2在胞浆和胞膜中表达增强,P-gp在胞浆和胞膜中表达减弱;细胞内游离ATP水平增加;ABC转运蛋白的转运功能增强。结论: BIO处理食管鳞癌细胞后增强了细胞的多药耐药。  相似文献   
43.
目的探讨转录抑制因子Snail表达与胃癌Lauren分型的关系。方法Western印迹检测肠型胃癌细胞系(N87)和弥漫型胃癌细胞系(AGS)中Snail和上皮型E钙黏蛋白(E-cadherin)的表达。将糖原合酶激酶.3B(GSK-3B)质粒转染胃癌细胞系,检测Snail和E-cadherin的表达变化。收集2000年2月至2005年12月间在复旦大学附属中山医院行胃癌根治术的77例术后组织标本.采用免疫组织化学染色检测Snail在胃癌组织中表达.并分析其与胃癌Lauren分型之间的关系。结果Snail在N87中低表达,在AGS中高表达;E-cadherin表达与Snail相反。转染GSK-3B后,胃癌细胞Snail表达显著下调,E-cadherin表达显著上调(P〈0.01)。使用不同浓度的GSK-3B抑制剂氯化锂处理后.胃癌细胞Snail表达显著上调,且具有明显浓度依赖性(P〈0.01)。21例肠型胃癌中Snail低表达16例,高表达5例;56例弥漫型胃癌中Snail低表达21例,高表达35例;肠型胃癌中Snail表达明显弱于弥漫型,差异有统计学意义(P〈0.01)。结论Snail的表达与胃癌Lauren分型有关.是一种潜在的确定胃癌分型的分子标志物。  相似文献   
44.
目的 探讨缺血预处理和缺血后处理对大鼠脑缺血再灌注时糖原合酶激酶-3β(GSK-3β)活性的影响.方法 雄性Wistar大鼠40只,体重200~230 g.随机分为4组(n=10),假手术组(S组)仅分离双侧颈总动脉;缺血再灌注组(I/R组)分离双侧颈总动脉,夹闭10 min后恢复灌注;缺血预处理组(IPR组)分离双侧颈总动脉,夹闭10 s,开放30 s,反复3次,最后夹闭10min后恢复灌注;缺血后处理组(IPO组)分离双侧颈总动脉,夹闭10 min,开放30s,夹闭10 s,反复3次后恢复灌注.于术后2 d时取脑组织,计数大脑皮质凋亡神经元,测定脑梗死体积、磷酸化GSK-3β(p-GSK-3β)、Bcl-2、Bax、Caspase-3表达.对神经元凋亡数、脑梗死体积与p-GSK-3β水平做直线相关分析.结果 与S组比较,I/R组、IPR组和IPO组凋亡神经元、脑梗死体积增加,p-GSK-3β水平降低,Bcl-2表达下调,Bax和Caspase-3表达上调(P<0.05);与I/R组比较,IPR组和IPO组凋亡神经元和脑梗死体积降低,p-GSK-3β水平升高,Bcl-2表达上调,Bax和Caspase-3表达下调(P<0.05);IPR组和IPO组间上述指标比较差异无统计学意义(P>0.05).凋亡神经元、脑梗死体积与p-GSK-3β水平呈负相关(P<0.05).结论 缺血预处理和缺血后处理通过抑制GSK-3β活性而减轻大鼠脑缺血再灌注损伤.  相似文献   
45.
目的观察茶多酚(polyphenols of tea,PPT)对胃缺血再灌注致胃黏膜毛细血管内皮超微结构损伤的保护作用。方法将30只雄性sD大鼠随机分成6组(n=5):空白对照组、手术组、20mg/kg PPT组、40mg/kg PPT组、80mg/kg PPT组、160mg/kg PPT组。在成功制作胃缺血动物模型的基础上,观察大鼠胃缺血30min后再灌注12h胃黏膜组织毛细血管内皮细胞超微结构的变化。结果茶多酚可显著减轻胃黏膜组织毛细血管内皮细胞超微结构的损伤。结论茶多酚对胃缺血再灌注致胃黏膜毛细血管内皮损伤具有保护作用,且存在剂量关系。  相似文献   
46.
Background and study aimsGlycogen storage disease type III (GSD III) is an autosomal recessive disorder caused by deficiency of glycogen debrancher enzyme and is characterised by clinical variability.Patients and methodsWe herein describe the clinical and laboratory findings in 31 Egyptian patients with GSD III presenting to the Paediatric Hepatology Unit, Cairo University, Egypt.ResultsEighteen patients (58%) were males. Their ages ranged between 6 months to 12 years. The main presenting complaint was progressive abdominal distention in 55%. Twelve patients (38.7%) had a history of recurrent attacks of convulsions; four had an erroneous diagnosis of hypocalcaemia and epilepsy. Doll-like facies was noted in 90%. Abdominal examination of all cases revealed abdominal distention and soft hepatomegaly which had bright echogenicity by ultrasound. Hypertriglyceridaemia was present in 93.6%, hyperlactacidaemia in 51.6% and hyperuricaemia in 19.4%. Liver biopsy showed markedly distended hepatocytes with well distinct cytoplasmic boundaries and 32% had macrovesicular fatty changes. Serum creatine kinase was elevated in 64.6% of patients and correlated positively and significantly with age (r = 0.7 and P = <0.001), while serum triglycerides correlated negatively with age (r = −0.4 and P = 0.05).ConclusionBlood glucose assessment and search for hepatomegaly in an infant with recurrent seizures may prevent delay in the diagnosis. A huge soft liver reaching the left midclavicular line that appears echogenic on ultrasonography is characteristic of GSD III. A distended hepatocyte with rarified cytoplasm is pathognomonic but not diagnostic. Hypertriglyceridaemia correlates negatively with age, in contrary to CK level.  相似文献   
47.
A case of chronic pancreatitis in an 8-year-old boy with glycogen storage disease type 1a (GSD 1a) is presented. This patient had a history of hyperlipidaemia unresponsive to dietary therapy, e.g., a carbohydraterich diet, uncooked cornstarch, and nocturnal intragastric tube feedings. He had recently suffered bouts of abdominal pain and diarrhoea. Serum amylase and trypsin were elevated, abdominal CT revealed the presence of a pseudocyst of the pancreas. The presence of chronic pancreatitis was confirmed by endoscopic retrograde cholangiopancreatography and an infected pseudocyst was removed at laparotomy.  相似文献   
48.
Twenty patients with enzymatically proven glycogen storage disease type III (GSD III) aged 3–30 years underwent cardiological evaluation. Seventeen showed subclinical evidence of cardiac involvement in form of ventricular hypertrophy on ECG. Of 16 patients in whom an ECG examination was performed, 13 had abnormal echocardiographic features. Only 2 patients had cardiomegaly on X-ray. The cardiac findings in 1 of the patients, a 25-year-old female with clinically evident cardiomyopathy are described in detail. In view of our findings, patients with established GSD III, should not only be investigated regarding their muscular involvement, but should also undergo a detailed evaluation of their cardiac status.Abbreviation GSD glycogen storage disease  相似文献   
49.
Radial bone mineral content (BMC) was measured using single photon absorptiometry in 11 prepubertal children, aged 3.4–12.6 years, with glycogen storage disease type 1 (GSD-1), 2 of whom were receiving granulocyte colony stimulating factor (G-CSF) therapy for chronic neutropenia. Patients were short (median height SD score –1.35, range –3.74 to –0.27), and had reduced BMC Z scores (median 1.79, range –6.35 to +0.27) and radial bone width Z scores (median –0.72, range –2.00 to +0.68). Those receiving G-CSF did not differ significantly from the rest of the group. Generally dietary calcium intake was low and urinary calcium excretion increased. Urinary lactate excretion was high but did not correlate with BMC Z scores. Factors regulating bone metabolism (parathyroid hormone and 25-hydroxy vitamin D concentrations) and markers of bone formation (osteocalcin and skeletal alkaline phosphatase) were not increased implying that there was no compensation for increased bone resorption.Conclusion Patients with GSD-1 may be at increased risk of fracture in later life and require close attention to metabolic control and calcium balance.  相似文献   
50.
Brunelle  F.  Tammam  S.  Odievre  M.  Chaumont  P. 《Pediatric radiology》1984,14(2):94-101
The authors report the ultrasound and angiographic features of adenomas occurring in children with glycogen storage disease. Seven cases from 83 patients were diagnosed either by ultrasound, preoperative angiography or during surgery. The lesions appear on ultrasound as multiple rounded intrahepatic masses. Their degree of echogenicity as well of vascularity on angiography is highly variable. Ultrasound is the modality of choice in detecting adenomas. No malignant degeneration was observed.  相似文献   
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