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971.
The effect of targeted magnetic nanoparticles on hepatoma and the underlying mechanism were examined. Nude mice transplanted with a human hepatoma cell line (HepG2 cells) were randomized into 5 groups, including: (1) group A, receiving normal saline, (2) group B, receiving 5-fluorouracil (5-Fu), (3) group C, receiving magnetic nanoparticles containing 5-Fu, (4) group D, consisting of treatment with magnetic nanoparticles containing 5-Fu and inside magnetic field and (5) group E, receiving pure magnetic nanoparticles and inside magnetic field. Morphological features of transplanted tumors in mice in each group were observed under transmission electron microscope (TEM). The expression of bcl-2/bax protein was immunohistochemically detected by SABC method. The results showed that a large number of apoptotic tumor cells were found in group B and group D under TEM. The expression of bcl-2 protein was significantly decreased and the expression of bax protein increased significantly in both group B and D as compared with those in group A, C and E (P〈0.01 for all). The decrease in bcl-2 and the increase in bax were more in group D as compared with group B (P〈0.01). It is concluded that the targeted magnetic nanoparticles containing 5-Fu can improve the chemotherapeutic effect of 5-Fu by decreasing bcl-2 expression, increasing bax expres- sion and inducing apoptosis of the liver cancer cells. 相似文献
972.
The inhibitory effects of parthenolide (PTL) on angiogenesis induced by multiple myeloma (MM) cells in vitro and the mechanism were investigated. Human MM line RPMI8226 cells were cultured in vitro. The effects of MM culture supernatant on the migration and tubule formation ability of human umbilical vein endothelial cells (HUVECs) treated with PTL were observed. By using Western blot, the expression of p65 and IкB-α in MM cells was detected. RT-PCR was used to assay the expression of VEGF, IL-6, MMP2 and MMP9 mRNA in MM cells. ELISA was used to measure the levels of VEGF and IL-6 in MM cell culture supernatant. The expression of MMP2 and MMP9 in MM cells was examined by immunohistochemistry. (1) In 3.5, 5.0, 7.5 and 10 μmol/L PTL groups the number of migrated cells was 310±56, 207±28, 127±21 and 49±10 respectively, which was significantly different from that in positive control group (598±47) (P〈0.01). In 3.5 and 5.0 μmol/L PTL groups the areas of capillary-like structures were 0.092±0.003 and 0.063±0.002 mm2, significantly less than in positive control group (0.262±0.012 mm2) (P〈0.01), but in 7.5 and 10 μmol/L PTL groups no capillary-like structures were found; (2) After treatment with different concentrations of PTL for 48 h, the expression of p65 protein was gradually decreased, while that of IкB-α was gradually enhanced with the increased concentration of PTL; (3) After treatment with 3.5, 5.0, 7.5 and 10 μmol/L PTL for 48 h, the VEGF levels in the supernatant were 2373.4±392.2, 1982.3±293.3, 1247.0±338.4 and 936.5±168.5 pg/mL respectively, significantly different from those in positive control group (2729±440.0 pg/mL) (P〈0.05). After treatment with 7.5 and 10 μmol/L PTL, the IL-6 levels in the culture supernatant were 59.6±2.8 and 41.4±9.8 pg/mL respectively, signifi- cantly lower than in positive control group (1287.3±43.5 pg/mL) (P〈0.05); (4) RT-PCR revealed that PTL could significantly inhibit the expression of V 相似文献
973.
目的 探讨异基因造血干细胞移植时,供体CD8 T细胞致受体人脐静脉内皮细胞(HUVEC)凋亡中A20蛋白及Caspase 3的表达及意义.方法 采用密度梯度法分离人周围血单个核细胞,CD8 T细胞亚群阴性分选柱试剂盒分选出CD8 T细胞.HUVEC细胞株经过5 ng/ml TNF-α处理后与CD8 T细胞进行混合培养.以AnnexinⅤ和PI双标后,流式细胞仪对HUVEC进行凋亡分析,用全波长荧光分光光度计测定凋亡相关蛋白Caspase 3的活性.Western blot法检测HUVEC中A20蛋白的表达.结果 异基因CD8 T细胞在与HUVEC混合后可引起HUVEC凋亡,流式细胞仪检测显示24 h时的早期凋亡率最高,达(83.6±0.42)%.而晚期凋亡相关蛋白Caspase 3活性在48 h时达高峰,荧光强度为(13.585±0.269), 此后显著降低,与对照组比较差异有极显著性意义(P<0.01).A20蛋白的表达与HUVEC的凋亡率呈负相关(r=-0.839, P<0.05).结论 体外供体CD8 T细胞致受体HUVEC凋亡过程中,信号蛋白Caspase 3的激活介导了凋亡的发生,而A20可能对其起负调节作用. 相似文献
974.
Epidemiological evidence indicates that aflatoxin B1 (AFB1) intake is
associated with an increased risk of hepatocellular carcinoma (HCC). The
hepatocarcinogenesis is initiated by covalent binding of AFB1 to cellular
DNA. To determine whether nutritional factors and hormonal status may
influence the binding of AFB1 to hepatic DNA, a cross- sectional study was
performed on a total of 42 male asymptomatic hepatitis B surface antigen
(HBsAg) carriers and 43 male non-carriers in a cohort study on the
multistage development of HCC in Taiwan. The major AFB1-DNA adduct in vivo,
AFB1-N7-guanine, was measured by high- performance liquid chromatography in
urine. Urinary AFB1-N7-guanine was detectable in 40% of the subjects. HBsAg
carriers had a higher detection rate of urinary AFB1-DNA adducts than
non-carriers and the difference was statistically significant after
multivariate adjustment. After taking into account the total AFB1 urinary
metabolite level, chronic HBsAg carrier status, and other potential
confounders, plasma levels of cholesterol, alpha-tocopherol, and alpha- and
beta-carotene were positively associated with the detection rate of the
AFB1-DNA adducts in a dose-dependent manner, whereas plasma lycopene level
was inversely related to the presence of the adducts in urine. The
association of urinary AFB1-DNA adducts with the plasma levels of
cholesterol, alpha-tocopherol, lycopene, and alpha- and beta-carotene was
observed at both low and high exposure levels of AFB1. There was a
synergistic interaction of plasma alpha-tocopherol with alpha- and beta-
carotene on the adduct levels. No association with the adducts was found
for plasma levels of retinol and testosterone. This study demonstrated
different associations of antioxidant vitamins with AFB1- DNA adduct
formation. The data consistent with our previous finding in cultured
woodchuck hepatocytes that alpha-tocopherol and beta-carotene enhanced
AFB1-DNA adduct formation suggest that prospective investigation of the
relationship between plasma micronutrients and risk of AFB1-related HCC is
warranted.
相似文献
975.
胃癌组织中细胞凋亡和bcl-2基因蛋白表达的研究 总被引:3,自引:0,他引:3
目的:为了探讨细胞凋亡和bcl-2基因蛋白与胃癌之间的关系。方法:采用原位末端标记技术和免疫组化法对40例胃癌、25例胃粘膜组织中细胞凋亡和bcl-2基因蛋白进行检测。结果:胃癌组织中80.0%(32/40)凋亡细胞为( ),7.5%(3/40)为( );胃粘膜组织中80.0%(20/25)为( ),20.0%(5/25)为( )。85.0%(34/40)的胃癌bcl-2基因蛋白表达阳性,64.0%(16/25)的胃小凹底部上皮bcl-2基因蛋白表达阳性,而表面上皮则不表达。结论:细胞凋亡受抑制和bcl-2基因蛋白过表达与胃癌的发生有密切关系。 相似文献
976.
为了研究Bcl-2和p53基因蛋白与阴茎癌的关系,应用PAP免疫组化法对46例阴茎癌组织中Bcl-2和p53基因蛋白进行检测。结果显示,正常鳞状上皮基底细胞Bcl-2蛋白表达阳性,46例阴茎癌中有38例(82.6%)Bcl-2蛋白表达阳性,有11例(23.9%)p53蛋白表达阳性。提示两种癌基因蛋白的过度表达参与了阴茎癌的发生发展过程。 相似文献
977.
The present study observed the effects of superoxide diamutase (SOD) and its Inhibitor, diethyldithiocarbamate (DDC), on the metastasis of Lewis Lung cancer and some biological characteristics of A548 lung cancer cell line. It was found that SOD and DDC inhibited significantly the metastasis of Lewis lung cancer In C57 BL mice, which the effect of DDC was more significant than that of SOD, and decreased the proliferation of A549 lung cancer cell and its transplantation rate in nude mice. 相似文献
978.
Colles‘骨折固定体位的探讨(附56例疗效分析) 总被引:1,自引:0,他引:1
通过对临床实践中正反两方面经验和教训的总结,根据腕部解剖、生理及骨折后的病理特点,分析比较了56例Colles’骨折患者复位后分别采用腕掌屈前臂旋前位与腕背伸前臂旋后位两种不同固定方法的优劣。结果表明,骨折再移位发生率后者明显低于前者;而功能恢复情况后者明显优于前者(P<0.01)。揭示腕背伸前臂旋后位固定不仅利于骨折复位后的稳定,而且有利于骨折愈合和功能恢复。因此主张摒弃传统的腕掌屈前臂旋前位固定,采用腕背伸前臂旋后位固定。 相似文献
979.
T Güng?r E Rohrbach E Solem JP Kaltwasser B Kornhuber 《Archives of disease in childhood》1996,74(4):323-327
Nineteen children and adolescents receiving repeated transfusions and subcutaneous desferrioxamine treatment were investigated in an attempt to quantitate iron overload non-invasively. Before patients were started on desferrioxamine individual relationships were correlated for 12 to 36 months between transfused iron, absorbed iron estimated gastrointestinally, and increasing serum ferritin concentrations. Patients with inflammation, increased liver enzymes, or haemolysis were excluded from analysis. The relationship between the variables could be described by a logarithmic regression curve (y = transfused iron [plus eventually gastrointestinally absorbed iron] = iron overload = a+b log [x = serum ferritin]) for each individual patient. All patients showed close correlation (R2) between x and y (median R2 of 0.909, 0.98, and 0.92 in thalassaemia, aplastic anaemia, and sickle cell anaemia patients, respectively). When started on desferrioxamine, current serum ferritin concentrations were used to derive the iron overload from each individual regression curve. The derived estimated iron overload ranged from 0.6 g to 31 g. Left ventricular dilatation was observed in three patients with beta thalassaemia and in one patient with aplastic anaemia with median iron overload of 20.7 (14.1-31.3) g and 24.0 g respectively. Hypothyroidism was found in four patients with beta thalassaemia and one patient with aplastic anaemia with iron overload between 14.7 (6.8 and 26.1) g and 15.1 g respectively. Human growth hormone deficiency was detected in three patients with beta thalassaemia with an iron overload of 4.2 (3.5-6.8) g; all three patients had excellent desferrioxamine compliance. 相似文献
980.
Bacterial endocarditis is an uncommon diagnosis in childhood with significant morbidity and mortality. Aortic aneurysm as a complication is well described in adults but there are few reports in the paediatric literature. Two children with bacterial endocarditis are described, whose illnesses were complicated by aortic aneurysm formation requiring surgical intervention. 相似文献