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1.
Nonalcoholic fatty liver disease (NAFLD) is a strong stimulant of cardiovascular diseases, affecting one-quarter of the world's population. TBC1 domain family member 25 (TBC1D25) regulates the development of myocardial hypertrophy and cerebral ischemia–reperfusion injury; however, its effect on NAFLD/nonalcoholic steatohepatitis (NASH) has not been reported. In this study, we demonstrated that TBC1D25 expression is upregulated in NASH. TBC1D25 deficiency aggravated hepatic steatosis, inflammation, and fibrosis in NASH. In vitro tests revealed that TBC1D25 overexpression restrained NASH responses. Subsequent mechanistic validation experiments demonstrated that TBC1D25 interfered with NASH progression by inhibiting abnormal lipid accumulation and inflammation. TBC1D25 deficiency significantly promoted NASH occurrence and development. Therefore, TBC1D25 may potentially be used as a clinical therapeutic target for NASH treatment.  相似文献   
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腺苷酸激酶基因在大肠杆菌中的可溶性高表达   总被引:6,自引:0,他引:6  
报道了鸡肌腺苷酸激酶基因的克隆和在温控启动子PRPL调控下在大肠杆菌中的可溶性高效表达.SDS-PAGE分析表明,鸡肌腺苷酸激酶的含量可占大肠杆菌细胞总蛋白含量的38%.利用Johnson等的干冰/乙醇-冰水浴反复冻融法,可将此重组蛋白进行富集,纯度可达85%以上.鸡肌腺苷酸激酶可与抗兔肌腺苷酸激酶单克隆抗体产生强的交叉反应.  相似文献   
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Cerebral glucose metabolism is a reliable index of neural activity and may provide evidence for brain function in healthy adults. We studied the correlation between cerebral glucose metabolism and age under the resting-state in both sexes with position emission tomography. Statistical test of age effect on cerebral glucose metabolism was performed using the statistical parametric mapping software with a voxel-by-voxel approach ( family wise error corrected, -voxel threshold). The subjects consisted of 108 females (mean S.D. = 4510 years) and 126 males (mean S.D. = 4911 years). We showed here that brain activity in the frontal and temporal lobes in both sexes decreased significantly with normal aging. The glucose metabolism in the caudate bilaterally showed a negative correlation with age in males, but not in females. Few regions in males were shown with an increased glucose metabolism with age. Although the mechanisms of brain aging are still unknown, a map of brain areas susceptible to age was described in this report.  相似文献   
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连香树(Cercidiphyllum japonicum)是第三纪孑遗植物, 存在严重的幼苗更新限制。为验证生活史早期(种子萌发)限制中国分布区北缘连香树种群幼苗更新, 并探讨其主要成因, 本研究在秦岭和太行山脉采集不同种源地的种子, 测定其形态性状、营养元素含量和质量、不同贮存时间的活力及不同温度条件下的萌发性状, 通过方差分析、相关分析等方法对不同种源地的种子性状进行分析。结果表明: 在中国分布区北缘, 其种子长度(P < 0.001)、萌发率(P < 0.001)、平均萌发时间(P < 0.001)、氮(P < 0.05)和磷含量(P < 0.001)在不同种源间存在显著差异; 而在区域尺度上(秦岭与太行山), 仅种子碳含量存在显著差异(P < 0.01)。天水种群的种子萌发率最高(21.77%), 平均萌发时间最长(11.12 d); 栾川的萌发率最低(1.38%), 平均萌发时间最短(3.47 d)。在25℃条件下, 济源种群的种子萌发率显著高于10℃、15℃和20℃条件下(P < 0.05), 而其他种源地的萌发率在不同温度条件下无显著差异。在4个温度条件下, 栾川种群种子的初始萌发时间无显著差异, 而其他4个种源地的初始萌发时间都随温度升高而缩短。相关分析结果表明, 种子萌发率与种子活力密切相关, 而种子活力与种子质量、种子的氮和磷含量显著相关。在中国分布区北缘, 连香树种子的自身属性(质量、氮和磷含量)通过影响种子活力间接影响萌发率; 且种子萌发对温度的响应主要表现在萌发时间上。本研究证实种子萌发是限制连香树种群幼苗更新的关键阶段, 主要原因如下: (1)连香树种子在9月成熟后, 10月的温度仍适宜种子萌发, 但较短生长期的幼苗在冬季低温下不能存活; (2)连香树种子萌发率低(14.4%); (3)第二年春天种子活力骤降。  相似文献   
6.
目的探讨呼吸机相关性肺炎患者病原菌分布及血清高迁移率族蛋白1(HMGB1)和可溶性髓系细胞触发受体-1(sTREM-1)的变化。方法选取我院2016年3月至2019年5月收治的131例呼吸机相关性肺炎患者进行研究,检测入选患者病原菌感染情况,同时根据患者病情分为重症组与非重症组。另选取60例同期体检对象作为对照组,比较各组患者血清sTREM-1、HMGB1水平及临床肺部感染评分(CPIS),分析血清sTREM-1、HMGB1对呼吸机相关性肺炎的预测价值。结果 131例患者共检出病原菌415株,病原菌以革兰阴性菌为主,其次是革兰阳性菌,真菌的占比最低。革兰阴性菌中以铜绿假单胞菌和肺炎克雷伯菌为主,革兰阳性菌中以金黄色葡萄球菌为主。重症组、非重症组及对照组患者血清sTREM-1、HMGB1水平及CPIS评分依次递减,组间比较差异均有统计学意义(均P0.05)。Cochran Armitage趋势检验发现,血清sTREM-1、HMGB1水平及CPIS评分与呼吸机相关性肺炎严重程度呈线性增加趋势(Z=5.056、3.127、3.811,均P0.05)。诊断呼吸机相关性肺炎病情严重程度时,血清sTREM-1的AUC及敏感性、特异性最高,其次是CPIS和血清HMGB1,3个指标均对呼吸机相关性肺炎有一定诊断价值。结论革兰阴性菌是呼吸机相关性肺炎的主要致病菌,血清sTREM-1、HMGB1水平对呼吸机相关性肺炎的病情有一定诊断价值。  相似文献   
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We report a facile one‐pot sonochemical approach to preparing highly water‐soluble Ag nanoclusters (NCs) using bovine serum albumin as a stabilizing agent and reducing agent in aqueous solution. Intensive electrogenerated chemiluminescence (ECL) was observed from the as‐prepared Ag (NCs) and successfully applied for the ECL detection of dopamine with high sensitivity and a wide detection range. A possible ECL mechanism is proposed for the preparation of Ag NCs. With this method, the dopamine concentration was determined in the range of 8.3 × 10–9 to 8.3 × 10–7 mol/L without the obvious interference of uric acid, ascorbic acid and some other neurotransmitters, such as serotonin, epinephrine and norepinephrine, and the detection limit was 9.2 × 10–10 mol/L at a signal/noise ratio of 3. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
9.
Pancreatic fibrosis, a prominent histopathological feature of chronic pancreatitis (CP) and pancreatic ductal adenocarcinoma, is essentially a dynamic process that leads to irreversible scarring of parenchymal tissues of the pancreas. Though the exact mechanisms of its initiation and development are poorly understood, recent studies suggested that the activation of pancreatic stellate cells (PSCs) plays a critical role in eliciting such active course of fibrogenesis. Anthraquinone compounds possess anti-inflammatory bioactivities whereas its natural derivative rhein has been shown to effectively reduce tissue edema and free-radical production in rat models of inflammatory conditions. Apart from its anti-inflammatory properties, rhein actually exerts strong anti-fibrotic effects in our current in-vivo and in-vitro experiments. In the mouse model of cerulein-induced CP, prolonged administration of rhein at 50 mg/kg/day significantly decreased immunoreactivities of the principal fibrotic activators alpha-smooth muscle actin (α-SMA) and transforming growth factor-beta (TGF-β) on pancreatic sections implicating the activation of PSCs, which is the central tread to fibrogenesis, was attenuated. Consequently, the overwhelmed deposition of extracellular matrix proteins fibronectin 1 (FN1) and type I collagen (COL I-α1) in exocrine parenchyma was found accordingly reduced. In addition, the expression levels of sonic hedgehog (SHH), which plays important roles in molecular modulation of various fibrotic processes, and its immediate effector GLI1 in pancreatic tissues were positively correlated to the degree of cerulein-induced fibrosis. Such up-regulation of SHH signaling was restrained in rhein-treated CP mice. In cultured PSCs, we demonstrated that the expression levels of TGF-β-stimulated fibrogenic markers including α-SMA, FN1 and COL I-α1 as well as SHH were all notably suppressed by the application of rhein at 10 μM. The present study firstly reported that rhein attenuates PSC activation and suppresses SHH/GLI1 signaling in pancreatic fibrosis. With strong anti-fibrotic effects provided, rhein can be a potential remedy for fibrotic and/or PSC-related pathologies in the pancreas.  相似文献   
10.
There is a critical need for mapping early metabolic changes in schizophrenia to capture failures in regulation of biochemical pathways and networks. This information could provide valuable insights about disease mechanisms, trajectory of disease progression, and diagnostic biomarkers. We used a lipidomics platform to measure individual lipid species in 20 drug-naïve patients with a first episode of schizophrenia (FE group), 20 patients with chronic schizophrenia that had not adhered to prescribed medications (RE group), and 29 race-matched control subjects without schizophrenia. Lipid metabolic profiles were evaluated and compared between study groups and within groups before and after treatment with atypical antipsychotics, risperidone and aripiprazole. Finally, we mapped lipid profiles to n3 and n6 fatty acid synthesis pathways to elucidate which enzymes might be affected by disease and treatment. Compared to controls, the FE group showed significant down-regulation of several n3 polyunsaturated fatty acids (PUFAs), including 20:5n3, 22:5n3, and 22:6n3 within the phosphatidylcholine and phosphatidylethanolamine lipid classes. Differences between FE and controls were only observed in the n3 class PUFAs; no differences where noted in n6 class PUFAs. The RE group was not significantly different from controls, although some compositional differences within PUFAs were noted. Drug treatment was able to correct the aberrant PUFA levels noted in FE patients, but changes in re patients were not corrective. Treatment caused increases in both n3 and n6 class lipids. These results supported the hypothesis that phospholipid n3 fatty acid deficits are present early in the course of schizophrenia and tend not to persist throughout its course. These changes in lipid metabolism could indicate a metabolic vulnerability in patients with schizophrenia that occurs early in development of the disease.  相似文献   
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