蛋白激酶C在软脂酸诱导HepG2细胞胰岛素抵抗中的作用

目的从蛋白激酶C(PKC)信号通路角度,探讨游离脂肪酸(FFA)引起肝脏胰岛素抵抗(IR)的可能机制。方法培养HepG2细胞,同时设立对照组、软脂酸(PA)组、高胰岛素组。软脂酸组、高胰岛素组分别用250μmol/L PA、5×10-7mol/L胰岛素处理24h。然后对照组、软脂酸组再根据胰岛素刺激前加( )与不加(-)PKC抑制剂白屈菜红碱盐酸盐(chelerythrine chloride,CC)5μmol/L预处理1h,随机分为两亚组:对照组(-)、对照组( )、PA组(-)、PA组( )。葡萄糖氧化酶法测定胰岛素刺激后12h葡萄糖消耗量,蒽酮法测定胰岛素刺激后3h点细胞内糖原含量,Western blotting技术检测15min点细胞内P-Ser473PKB、P-Ser21/9GSK-3α/β水平。结果PA组(-)与高胰岛素组葡萄糖消耗量无统计学差异(P=0.523)。葡萄糖消耗量、细胞内糖原含量、P-Ser473PKB、P-Ser21GSK-3α、P-Ser9GSK-3β水平均显示,PA组(-)与对照组(-)比较显著降低(P值依次为0.000,0.000,0.004,0.004,0.028),对照组( )与对照组(-)比较略有升高但无显著性差异;PA组( )与PA组(-)比较显著升高(P值依次为0.000,0.014,0.043,0.041,0.035)。结论PA(250μmol/L)体外成功诱导了HepG2细胞产生IR,PKC信号通路在FFA引起肝脏IR中起着重要作用。     

Pretreatment with Tongxinluo protects porcine myocardium from ischaemia/reperfusion injury through a nitric oxide related mechanism

Background The traditional Chinese medicine Tongxinluo can protect myocardium against ischaemia/reperfusion injury, but the mechanism of its action is not well documented. We examined the involvement of nitric oxide in the protective role of Tongxinluo. Methods Miniswine were randomized to four groups of seven: sham, control, Tongxinluo and Tongxinluo coadministration with a nitric oxide synthase inhibitor Nω-nitro-L-arginine (L-NNA, 10 mg/kg i.v.). Three hours after administration of Tongxinluo, the animals were anaesthetised and the left anterior descending coronary artery ligated and maintained in situ for 90 minutes followed by 3 hours of reperfusion before death. Area of no reflow and necrosis and risk region were determined pathologically by planimetry. The degree of neutrophil accumulation in myocardium was obtained by measuring myeloperoxidase activity and histological analysis. Myocardial endothelial nitric oxide synthase activity and vascular endothelial cadherin content were measured by colorimetric method and immunoblotting analysis respectively.Results Tongxinluo significantly increased the local blood flow and limited the infarct and size of no reflow. Tongxinluo also attenuated myeloperoxidase activity and neutrophil accumulation in histological sections and maintained the level of vascular endothelial cadherin and endothelial nitric oxide synthase activity in the reflow region when compared with control group. The protection of Tongxinluo was counteracted by coadministration with L-NNA. Conclusions Tongxinluo may limit myocardial ischaemia and protect the heart against reperfusion injury. Tongxinluo regulates synthesis of nitric oxide by altering activity of endothelial nitric oxide synthase.     

非酒精性脂肪性肝炎大鼠肝脏内毒素受体表达上调

目的观察大鼠非酒精性脂肪性肝炎(NASH)伴肝纤维化模型形成过程中,肝脏内毒素受体表达的动态变化,以探讨NASH的发病机制。方法 45只雄性SD大鼠以高脂饮食喂养,分批于实验 8,12、16、24周处死。免疫组织化学法观察CD14表达,逆转录聚合酶链反应(RT-PCR)法观察4型toll 样受体(TLR4)mRNA表达,RT-PCR法和酶联免疫吸附法分别测定肝脏和血清肿瘤坏死因子a(TNF a) 表达。同期正常饮食饲养大鼠作对照。结果实验8周大鼠单纯性脂肪肝阶段肝脏CD14和TLR4的表达就较正常对照上调(25．9±11．9对12．4 5．7、1．75±0．81对O．98±0．33,P<0．01和P<0．05),12周随着脂肪性肝炎的出现进行性增高(61．8±21．9和1．88±0．72,P值均<0．05),于16周达高峰(71．5±21．3 对5．64±0．87,P值均<0．01),24周略有回落(67．7±16．6和4．98±0．72,P值均<0.01)。肝脏和血清 TNF a表达也从8周开始上调,此后一直维持高水平表达。结论大鼠NASH形成过程中,肝脏内毒素受体CD14和TLR4表达逐渐上调。这可能是NASH大鼠内毒素肝损伤敏感性增强的原因之一,在NASH的发病中起了重要作用。     

Role of cytochrome P4502E1 in alcoholic liver disease pathogenesis

The intragastric tube feeding model is ideal for the study of the role of dietary factors and the effect of drugs on experimental alcoholic liver disease (ALD), since the model allows us to study the effect of a single variable in the diet on the pathology of liver where the blood alcohol level (BAL) is maintained over 150 mg%. By varying the dietary fatty acid composition we showed that the pathology was worsened by increasing linoleic acid or polyunsaturated fatty acids (PUFAs) in the diet where cytochrome P4502E1 (CYP2E1) was increased posttranslationally by high BAL. Concomitant with the increase in CYP2E1 there was evidence for an increase in lipid peroxidation (LP) by microsomes. Protein adducts of the products of LP were increased in the blood. Isoniazid (INH) enhanced this process and the pathology of ALD when INH was fed at therapeutic levels with ethanol. Preliminary studies show that diallyl sulfide, which inhibits and destroys liver CYP2E1 selectively, also modified the pathologic effects of ethanol. Thus we postulate that CYP2E1 induction plays a central role in the pathogenesis of ALD.     

人类转移癌间质淋巴样细胞漫润及其意义的探讨

观察126例人类转移癌,分析比较淋巴样细胞浸润(LI)程度与患者年龄、病理类型、组织分化和核异型程度的关系。结果表明:患者年龄及病理类型与LI程度无关;组织分化程度在LI上虽有差别,但无对应性关系;而核异型程度与LI关系密切。核异型性愈明显,LI程度愈高,反之亦然。这说明核分级不仅可以反映宿主免疫反应的高低,也可提示转移癌抗原性的强弱。     

MRI gadolinium enhancement of bone marrow: age-related changes in normals and in diffuse neoplastic infiltration

 Objective: To quantify gadolinium-related enhancement in the bone marrow of the spine in normals and in patients with homogeneous diffuse malignant bone marrow infiltration. Design and patients: The patients consisted of two groups: group 1 comprised 94 healthy adults (18–86 years) without bone marrow disease and group 2 comprised 30 patients with homogeneous diffuse malignant bone marrow infiltration due to myeloma (n=20) or breast carcinoma (n=10). All patients received intravenous gadopentetate dimeglumine (Gd-DTPA), 0.1 mmol/kg body weight. Pre- and postcontrast signal intensity (SI) on T1-weighted spin-echo (SE) images (TR/TE: 572 ms/15 ms) was measured over a region of interest (ROI) and the percentage SI increase was calculated. The results were confirmed by bone marrow biopsy (n=20) and clinical parameters (n=10). Dynamic contrast-enhanced studies using a spoiled gradient-recalled-echo (GRE) sequence (TR/TE/α: 68 ms/6 ms 75°) were performed in 10 controls with normal bone marrow. Results and conclusion: Contrast material enhancement in healthy persons can vary greatly (range 3–59%, mean 21%, SD 11%). With increasing age there is a significant decrease in contrast enhancement (Pearson’s correlation, P<0.01). The percentage SI increase in patients with intermediate-grade (biopsy 20–50 vol%) and high-grade (biopsy >50 vol%) diffuse malignant bone marrow infiltration was significantly higher than in normals (mean 67%, SD 34%, P<0.001). Low-grade (biopsy <20 vol%) diffuse malignant bone marrow infiltration can not be assessed by non-enhanced T1-weighted SE images or Gd-DTPA application. In conclusion, contrast material enhancement in healthy persons can vary greatly and is dependent on age, while intermediate-grade and high-grade diffuse malignant bone marrow infiltration can be objectively assessed with SI measurements.     

小鼠原位脂肪肝移植模型的建立

目的　建立了ob/ob小鼠脂肪肝移植模型 ,探讨保证建模成功的关键因素。方法　采用小鼠非动脉化肝移植技术 ,5～ 7周肥胖小鼠为供体 ,正常小鼠为受体 ,双袖套法行原位肝移植。受体肝组织行HE染色和油红O染色 ,血清ALT、AST水平检测采用常规生化分析法。结果非脂肪肝移植组 (lean to lean)受体长期存活率 (n =10 )为 70 % ,脂肪肝移植组 (ob/obtoagematchedlean)受体存活率为 0 (n =10 ) ,差异有显著性 (P <0 .0 5 )。脂肪肝移植给体积相当的正常小鼠 ,其短期存活率为 3 0 % (n =10 ) ,所有小鼠术后存活并苏醒 ,但均未超过 2 4h。脂肪肝移植受体ALT水平为 (62 85± 2 93 7)U /L ,AST为 (5 812± 2 942 )U /L ;而正常小鼠移植组ALT与AST水平分别为 (5 96± 114 )U /L ,(1796± 870 )U/L ,差异有显著性 (P <0 .0 5 ) ,组织学检测显示大量胆管中央凝固性坏死伴出血。结论　该模型的成功建立为我们提供了一种新的肝原发性肝无功能移植模型 ,为脂肪肝移植后脂肪肝细胞受损的机制研究奠定了基础。     

CT图象的面罩式覆盖法定量诊断脂肪肝

目的　探讨脂肪肝的脂肪浸润程度的无创性检查方法及临床意义。方法　用 GE 30 0 0 I CT机扫描 36例脂肪肝患者肝脏、脾脏 ,用 CT机配备软件处理数据 ,面罩式覆盖法计算肝脏各个层面的脂肪面积与对应层面肝脏面积 ,并得出比值 (脂肪浸润指数 )。用生化仪检测肝功能指标。肝穿刺病理检测肝组织内脂肪浸润程度。结果　平均脂肪浸润指数与肝功能状态呈显著正相关 ,亦与肝穿刺的病理结果呈正相关 (r=0 .86 5 ,P<0 .0 1)。结论　 CT图象面罩式覆盖法对脂肪浸润的定量分析是诊断脂肪肝可靠的无创性检查方法 ,对非均匀性脂肪肝该方法优于肝穿刺     

何首乌提取物对人乳腺癌细胞脂肪酸合酶的抑制研究

目的 研究何首乌提取物对人乳腺癌MCF7细胞脂肪酸合酶(fatty acid synthase，FAS)的抑制作用。方法 MTT法测定人乳腺癌MCF7细胞增殖速度，采用超速离心技术部分纯化人乳腺癌MCF7细胞FAS。不同浓度何首乌提取物与FAS相互作用不同时间后，加入底物，用分光光度法观察何首鸟提取物对FAS的抑制作用。结果 何首鸟提取物对人乳腺癌MCF7细胞的增殖有一定的抑制作用。人乳腺癌MCF7细胞FAS被部分纯化，三种浓度何首乌提取物(0．1，0．5，1g／L)与FAS在催化前相互作用0、5和10min，对FAS活性的抑制率分别为24．60％、27．30％、and42．75％(0．1g／L)；43．50％、50．30％、and94．03％(O．5g／L)；98．60％、97．30％ and97．05％(1g／L)。结论 何首乌提取物对人乳腺癌MCF7细胞FAS具有抑制作用；作用强度既依赖于抑制剂浓度，又依赖于抑制剂与酶相互作用时间。     

34例淋巴瘤骨髓浸润患者治疗与预后分析

目的 探讨淋巴瘤骨髓浸润患者的治疗与预后。方法 34例淋巴瘤骨髓浸润患者分为单纯化疗组、化疗+放疗组、大剂量化疗+自体干细胞移植组进行治疗,长期随访,分析其预后状况。结果 全组中位生存期为20个月;1年和3年生存率分别为76.47％和26.47％,最初疗效为完全缓解和部分缓解患者的1年和3年生存率均大于未缓解患者(P<0.05);大剂量化疗+自体干细胞移植组的3年生存率大于单纯化疗组和化疗+放疗组(P<0.05)。结论 淋巴瘤骨髓浸润患者的生存率与最初疗效有关;大剂量化疗+自体干细胞移植能提高其生存率,改善预后。