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991.
摘要 目的:探究氧化固醇结合蛋白类似物3(Oxysterol Binding Protein-like 3,OSBPL3)在代谢相关脂肪性肝病中的作用及可能机制。方法:建立肝脏特异性沉默OSBPL3小鼠模型和空载体对照组,分别予以普食和高脂喂养12周。分为正常对照组、OSBPL3沉默组、肥胖对照组、肥胖OSBPL3沉默组。观察小鼠一般情况,Real-time PCR检测脂质合成基因及脂质分解基因mRNA水平,western blot检测Akt/mTOR通路关键蛋白的表达。人HepG2细胞株给予不同浓度油酸(oleic acid,OA)处理,观察油红O染色的变化,western blot检测OSBPL3表达水平。结果:正常对照组与OSBPL3沉默组小鼠各项指标相比无统计学差异(P>0.05);与对照组相比,肥胖对照组及肥胖OSBPL3沉默组体质量、内脏脂肪及内脏脂肪指数较高(P<0.05);与肥胖对照组相比,肥胖OSBPL3沉默组体质量、内脏脂肪及内脏脂肪指数较低(P<0.05)。与对照组相比,肥胖对照组及肥胖OSBPL3沉默组总胆固醇(Total cholesterol,TC)、甘油三酯(triglycerides,TG)、高密度脂蛋白胆固醇(high density lipoprotein cholesterol,HDL-C)、低密度脂蛋白胆固醇(low density lipoprotein cholesterol,LDL-C)较高(P<0.05);与肥胖对照组相比,肥胖OSBPL3沉默组TC、TG、LDL-C及HDL-C较低(P<0.05)。与正常对照组与OSBPL3沉默组小鼠SREBP-1C、FAS及PPARα表达水平相比无统计学差异(P>0.05);与对照组相比,肥胖对照组及肥胖OSBPL3沉默组SREBP-1C、FAS较高,PPARα表达水平较低(P<0.05);与肥胖对照组相比,肥胖OSBPL3沉默组SREBP-1C、FAS表达水平较低,PPARα表达水平较高(P<0.05)。与对照组相比,肥胖对照组Akt及mTOR磷酸化表达水平较高(P<0.05);与肥胖对照组相比,肥胖OSBPL3沉默组Akt及mTOR磷酸化表达水平较低(P<0.05)。随着OA作用浓度的升高,油红O染色逐渐加深。与0 μmol/L油酸相比,油酸以剂量依赖性方式增加HepG2细胞OSBPL3 mRNA水平(P<0.05)。结论:OSBPL3能够调控脂质代谢的表达,可能通过调控Akt/mTOR信号通路发挥生物学功能,有望为研究NAFLD疾病发生发展及治疗提供参考依据。  相似文献   
992.
摘要 目的:探讨宫颈癌组织微小核糖核酸(miRNA)-200b-5p、miR-424-5p表达与临床病理特征、磷脂酰肌醇3-激酶/蛋白激酶B/哺乳动物雷帕霉素靶蛋白(PI3K/AKT/mTOR)信号通路和预后的关系。方法:选取2016年7月~2019年6月西安市中心医院收治的123例宫颈癌患者,采用定量聚合酶链式反应(qPCR)检测癌组织与癌旁组织中miR-200b-5p、miR-424-5p、PI3K信使RNA(mRNA)、AKT mRNA、mTOR mRNA表达。分析miR-200b-5p、miR-424-5p表达与PI3K mRNA、AKT mRNA、mTOR mRNA表达的相关性及与临床病理特征的关系。采用K-M法绘制不同miR-200b-5p、miR-424-5p表达宫颈癌患者生存曲线。结果:与癌旁组织比较,宫颈癌组织中miR-200b-5p、miR-424-5p表达降低,PI3K mRNA、AKT mRNA、mTOR mRNA表达升高(P<0.05)。Pearson相关性分析显示,宫颈癌组织中miR-200b-5p、miR-424-5p表达与PI3K mRNA、AKT mRNA、mTOR mRNA表达均呈负相关,PI3K mRNA、AKT mRNA、mTOR mRNA表达呈两两相关(P<0.05)。miR-200b-5p、miR-424-5p表达与宫颈癌分化程度、国际妇产科联盟(FIGO)分期和淋巴结转移有关(P<0.05)。随访3年,123例宫颈癌患者累积生存率为62.60%(77/123)。K-M生存曲线分析显示,miR-200b-5p、miR-424-5p高表达组累积生存率分别高于miR-200b-5p、miR-424-5p低表达组(P<0.05)。结论:宫颈癌组织中miR-200b-5p、miR-424-5p低表达,与分化程度、FIGO分期、淋巴结转移、PI3K/AKT/mTOR信号通路和预后有关。  相似文献   
993.
摘要 目的:探究慢性牙周炎患者血清降钙素基因相关肽(CGRP)、前列腺素E2(PGE2)、CC趋化因子配体20(CCL20)与牙周临床指标和辅助性T淋巴细胞17/调节性T淋巴细胞(Th17/Treg)失衡的相关性。方法:选取2020年5月-2022年5月海南省妇女儿童医学中心收治的91例慢性牙周炎患者,根据其严重程度分为轻度组(39例)、中度组(36例)、重度组(16例),比较三组血清CGRP、PGE2、CCL20、牙周临床指标[出血指数(BI)、探诊深度(PD)、附着丧失(AL)、菌斑指数(PLI)]、外周血Th17细胞比例、Treg细胞比例、Th17/Treg比值,采用Pearson相关分析血清CGRP、PGE2、CCL20与牙周临床指标和Th17/Treg失衡的相关性。结果:与轻度组比较,中度组、重度组血清CGRP、Treg细胞比例显著降低(P<0.05),血清PGE2、CCL20、BI、PD、PLI、AL、Th17细胞比例、Th17/Treg比值显著增高(P<0.05);与中度组比较,重度组血清CGRP、Treg细胞比例显著降低(P<0.05),血清PGE2、CCL20、BI、PD、PLI、AL、Th17细胞比例、Th17/Treg比值显著增高(P<0.05)。相关性结果提示,血清PGE2、CCL20水平与BI、PD、PLI、AL、Th17细胞比例、Th17/Treg比值呈正相关(P<0.05),与Treg细胞比例呈负相关(P<0.05);血清CGRP水平与BI、PD、PLI、AL、Th17细胞比例、Th17/Treg比值呈负相关(P<0.05),与Treg细胞比例呈正相关(P<0.05)。结论:慢性牙周炎患者血清CGRP、PGE2、CCL20水平与疾病严重程度、牙周临床指标及Th17/Treg失衡显著相关,血清CGRP、PGE2、CCL20可能通过影响Th17/Treg平衡参与慢性牙周炎的发生和发展。  相似文献   
994.
摘要 目的:探讨血清载脂蛋白B(ApoB)/载脂蛋白A1(ApoA1)比值、三酰甘油(TG)/高密度脂蛋白胆固醇(HDL-C)比值、乳酸脱氢酶(LDH)及碱性磷酸酶(ALP)水平与冠心病(CHD)患者冠状动脉病变严重程度的关系及其预测价值。方法:选取2019年1月-2021年12月因胸痛来我院检查并收治的185例患者,根据检查结果是否为CHD分为CHD组(120例)和对照组(65例),根据Gensini评分将CHD组分为轻度狭窄亚组36例、中度狭窄亚组55例、重度狭窄亚组29例。入院后检测血清ApoB/ApoA1比值、TG/HDL-C比值、LDH及ALP水平。采用Spearman相关系数分析CHD患者血清ApoB/ApoA1比值、TG/HDL-C比值、LDH、ALP水平与Gensini评分的相关性,采用多因素Logistic回归分析CHD的影响因素;受试者工作特征(ROC)曲线分析血清ApoB/ApoA1比值、TG/HDL-C比值、LDH及ALP水平对CHD的预测价值。结果:与对照组比较,CHD组吸烟、饮酒、高血压、糖尿病比例和血清总胆固醇(TC)、TG、低密度脂蛋白胆固醇(LDL-C)、ApoB、ApoB/ApoA1比值、TG/HDL-C比值、LDH、ALP水平升高,HDL-C、ApoA1水平降低(P<0.05)。轻度、中度、重度狭窄亚组血清ApoB/ApoA1比值、TG/HDL-C比值、LDH及ALP水平依次升高(P<0.05)。CHD患者血清ApoB/ApoA1比值、TG/HDL-C比值、LDH、ALP水平与Gensini评分呈正相关(P均<0.001)。多因素Logistic回归分析显示,高血压、血清ApoB/ApoA1比值、TG/HDL-C比值、LDH、ALP水平升高为CHD的独立危险因素(P<0.05)。ROC曲线分析显示,血清ApoB/ApoA1比值、TG/HDL-C比值、LDH及ALP水平联合预测CHD的曲线下面积大于单独预测(P<0.05)。结论:血清ApoB/ApoA1比值、TG/HDL-C比值、LDH、ALP水平与CHD患者冠状动脉病变严重程度有关,且联合预测CHD的价值较高。  相似文献   
995.
摘要 目的:探讨盐酸艾司洛尔联合右美托咪定对肺癌患者应激反应和辅助性T细胞1(Th1)/Th2型细胞因子的影响。方法:选取武汉科技大学附属天佑医院2020年6月~2022年3月期间收治的肺癌根治术患者112例。按照随机数字表法将患者分为对照组(n=56,常规麻醉联合盐酸右美托咪定注射液)和研究组(n=56,对照组基础上联合盐酸艾司洛尔注射液)。对比两组苏醒质量、肺功能指标、应激反应指标、Th1/Th2型细胞因子和术后肺部并发症发生率变化情况。结果:研究组的呼吸恢复时间、定向力恢复时间、拔管时间短于对照组(P<0.05)。研究组术后肺部并发症发生率低于对照组(P<0.05)。研究组术毕动态肺顺应性(Cdyn)高于对照组,平台压(Pplat)、气道峰压(Ppeak)低于对照组(P<0.05)。研究组术毕皮质醇(Cor)、去甲肾上腺素(NE)及肾上腺素(E)低于对照组(P<0.05)。研究组术毕肿瘤坏死因子-α(TNF-α)、白细胞介素-2(IL-2)低于对照组(P<0.05),研究组术毕白细胞介素-10(IL-10)、转化生长因子-β1(TGF-β1)高于对照组(P<0.05)。结论:盐酸艾司洛尔联合右美托咪定用于肺癌根治术中,具有较好的麻醉效果,可有效减轻术中应激反应,调节免疫功能并保护肺功能,还可降低术后肺部并发症发生率。  相似文献   
996.
《遗传学报》2023,50(2):63-76
The phenomenon of planar cell polarity is critically required for a myriad of morphogenetic processes in metazoan and is accurately controlled by several conserved modules. Six “core” proteins, including Frizzled, Flamingo (Celsr), Van Gogh (Vangl), Dishevelled, Prickle, and Diego (Ankrd6), are major components of the Wnt/planar cell polarity pathway. The Fat/Dchs protocadherins and the Scrib polarity complex also function to instruct cellular polarization. In vertebrates, all these pathways are essential for tissue and organ morphogenesis, such as neural tube closure, left–right symmetry breaking, heart and gut morphogenesis, lung and kidney branching, stereociliary bundle orientation, and proximal–distal limb elongation. Mutations in planar polarity genes are closely linked to various congenital diseases. Striking advances have been made in deciphering their contribution to the establishment of spatially oriented pattern in developing organs and the maintenance of tissue homeostasis. The challenge remains to clarify the complex interplay of different polarity pathways in organogenesis and the link of cell polarity to cell fate specification. Interdisciplinary approaches are also important to understand the roles of mechanical forces in coupling cellular polarization and differentiation. This review outlines current advances on planar polarity regulators in asymmetric organ formation, with the aim to identify questions that deserve further investigation.  相似文献   
997.
Up-to-date information on the prevalence and trends of common mental disorders is relevant to health care policy and planning, owing to the high burden associated with these disorders. In the first wave of the third Netherlands Mental Health Survey and Incidence Study (NEMESIS-3), a nationally representative sample was interviewed face-to-face from November 2019 to March 2022 (6,194 subjects; 1,576 interviewed before and 4,618 during the COVID-19 pandemic; age range: 18-75 years). A slightly modified version of the Composite International Diagnostic Interview 3.0 was used to assess DSM-IV and DSM-5 diagnoses. Trends in 12-month prevalence rates of DSM-IV mental disorders were examined by comparing these rates between NEMESIS-3 and NEMESIS-2 (6,646 subjects; age range: 18-64 years; interviewed from November 2007 to July 2009). Lifetime DSM-5 prevalence estimates in NEMESIS-3 were 28.6% for anxiety disorders, 27.6% for mood disorders, 16.7% for substance use disorders, and 3.6% for attention-deficit/hyperactivity disorder. Over the last 12 months, prevalence rates were 15.2%, 9.8%, 7.1%, and 3.2%, respectively. No differences in 12-month prevalence rates before vs. during the COVID-19 pandemic were found (26.7% pre-pandemic vs. 25.7% during the pandemic), even after controlling for differences in socio-demographic characteristics of the respondents interviewed in these two periods. This was the case for all four disorder categories. From 2007-2009 to 2019-2022, the 12-month prevalence rate of any DSM-IV disorder significantly increased from 17.4% to 26.1%. A stronger increase in prevalence was found for students, younger adults (18-34 years) and city dwellers. These data suggest that the prevalence of mental disorders has increased in the past decade, but this is not explained by the COVID-19 pandemic. The already high mental disorder risk of young adults has particularly further increased in recent years.  相似文献   
998.
999.
Encompassing ca. 200 species distributed in paleotropical Africa and Asia, Amorphophallus is one of the largest genera of Araceae. In spite of the great economic interest in its glucomannan production, only a few studies have attempted to grasp the evolutionary history of this genus. In the current state of knowledge, four main clades, mostly linked to biogeographical delineation, have been identified from phylogenies based on a few genes. However, relationships among and within these clades still remain unclear, due to the rapid radiation that occurred during the early evolutionary history of the genus. Here, we generated genome skimming libraries for 43 specimens from 36 species distributed across the 4 clades, which allowed us to produce a phylogenetic matrix for a set of 71 plastid genes. Our phylogenies confirm the monophyly of these clades but show a new and well-resolved arrangement among these clades. Our analyses therefore provide a new scenario and timeline for the evolution of the main Amorphophallus clades, consistent with the morphological characteristics of the clades. The inferred scenario is also in agreement with climate dynamics and the onset of long-distance dispersal by the earliest migratory birds near the Oligocene/Miocene transition around 23 million years ago. Our study provides an up-to-date baseline to understand biogeographic and ecological processes that shaped the current diversity and distribution of Amorphophallus, paving the way for larger-scale phylogenomic studies based on plastid and nuclear genomes.  相似文献   
1000.
Twenty days after hatching, a single stock of Atlantic herring ( Clupea harengus L.) larvae, cultured in the presence of rotifers and Artemia nauplii but showing little or no active feeding behaviour, displayed clear signs of starvation. Three groups of fish were distinguished: group I was generally pinhead-shaped, tended to swim with a spinning motion and floated vertically; group 2 lay moribund on the bottom of the tank; group 3 showed normal, active swimming behaviour. Fatty acids of total lipid extracted from groups 1 and 2 differed from group 3 in having markedly reduced percentages of 20:5n-3, 22:6n-3, 20:1 and 22:1. We conclude that individuals within a single stock of cultured herring larvae respond differently to starvation and that this generates well defined behavioural differences which correlate with levels of n-3 polyunsaturated fatty acids (PUFA) in body lipid. The implications of these observations are discussed.  相似文献   
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