THE AUSTRALIAN FURNITURE INDUSTRY

Collections of cores and discs from trees were used to identify species and methods best suited for dendrochronological studies in Australia. Three Tasmanien species, Phyllocladus aspleniifolius, Athrotaxis cupressoides, and A. selaginoides, offer excellent potential, having clear rings that can be accurately dated, ages over 500 years, and variations in ring width that can be related to climatic factors. Nothofagus gunnii occasionally can be dated, although ages over 300 years are unlikely. Dacrydium franklinii, the oldest of Australian conifers, has clear annual rings but little year-to-year variability. Crossdating in Callitris is hindered in many areas by false rings, but has been successful at 2 sites near Perth. Growth rings are of varying quality in different Eucalyptus species, but may be crossdated in some areas.     

花斑糠疹与马拉色菌毛囊炎相关危险因素和致病菌分析

目的 研究花斑糠疹和马拉色菌毛囊炎的相关危险因素和致病菌特点,并比较其差异。方法 收集我院临床花斑糠疹和马拉色菌毛囊炎患者,均以1：1设置病例对照组,调查发病相关因素,采用SPSS16.0软件进行单因素和多因素Logstic回归分析。培养阳性菌株采用形态学和生理生化学方法鉴定到菌种,比较菌种分布。结果 共收集到163例花斑糠疹和132马拉色菌毛囊炎患者。单因素回归分析显示与花斑糠疹发病相关的因素有多汗和油性皮肤,与马拉色菌毛囊炎发病相关的因素有男性、潮湿环境、多汗、油性皮肤、刺激性食物、甜腻食物。多因素回归分析显示花斑糠疹的危险因素有多汗和油性皮肤,马拉色菌毛囊炎的危险因素有多汗、油性皮肤、男性和甜腻性食物。两种疾病致病菌均以合轴马拉色菌为优势菌,但糠秕马拉色菌在毛囊炎中占较高比例。结论 多汗和油性皮肤是花斑糠疹和马拉色菌毛囊炎共同的危险因素,而男性、甜腻性食物为马拉色菌毛囊炎独有的危险因素,两种疾病致病分布也存在统计学差异。     

硒化合物对人脐带间充质干细胞ROS和NO生成及NOS活性的影响

目的:通过观察不同的硒化合物对人脐带间充质干细胞(MSCs)一氧化氮(NO)、活性氧(ROS)的生成及一氧化氮合酶(NOS)活性的影响,初步探讨硒的免疫调节作用机制。方法:在MSCs培养的过程中,分别添加0.1μmol/L和0.5μmol/L亚硒酸钠[Se(Ⅳ)]、硒代胱氨酸(Se-Cys)、纳米硒(Nano-Se),采用硝酸还原酶法检测24 h和48 h MSCs NO和NOS活性的变化,通过DCFH-DA荧光探针检测细胞内ROS。结果:在24 h,对照组、0.1μmol/L和0.5μmol/L Se(Ⅳ)处理MSCs的NO水平分别是(18.13±6.80)μmol/L、(20.93±5.68)μmol/L和(16.73±5.03)μmol/L。在48 h,0.1μmol/L和0.5μmol/L Se(IV)处理MSCs的NO水平分别是(17.20±9.11)μmol/L(P0.05)和(9.98±4.35)μmol/L(P0.01),明显低于对照组的(26.23±4.35)μmol/L。Se(IV)对ROS和NOS有明显的抑制作用,Se-Cys和Nano-Se对NO、ROS的生成和NOS活性没有明显影响。结论:Se(Ⅳ)对MSCs NO、ROS的生成和NOS活性有明显的抑制效应。     

硒酵母中硒的化学形态分析与评价

 利用Ｔｒｉｓ－缓冲液－甘油提取法对硒酵母的化学形态进行了分析，并与透析法进行比较。结果表明，经过特殊工艺生产的硒酵母虽然总硒含量达到４０００μｇ／ｇ以上，但其中５０％以上的硒为硒蛋氨酸形态的蛋白质或其它大分子态硒，无机态硒仅占３％左右，而游离态硒只占０．０１％。说明硒酵母有广阔的开发前景，同时也为硒制剂提供了适宜的质量监测方法。     

偏硅酸钠抑制家兔外周血白细胞活性氧的生成

高血脂时外周血白细胞引爆和激活,产生过多活性氧(reactive oxygen species,ROS),抑制过量的ROS产生对于控制动脉粥样硬化(atherosclerosis,AS)发生发展具有重要意义[1].以往研究发现偏硅酸钠( Na2 SiO3)有抗炎效应[2].本实验观察Na2 Si03对家兔外周血白细胞ROS的抑制作用,为NaSi03抗AS机制提供进一步资料.1材料与方法1.1动物:清洁级新西兰家兔(河北医科大学动物中心,合格证号:1004218),雄性,体质量1500 ～2000 g.1.2制备ox-LDL:从健康家兔耳中动脉取血,沉淀法提取低密度脂蛋白,置硫酸铜( CuSO4)溶液中37℃氧化24h得氧化低密度脂蛋白(ox-LDL).     

汉黄芩素体外抗人胃癌SGC7901细胞的增殖、凋亡作用

 目的 探讨汉黄芩素对人胃癌SGC7901细胞增殖抑制和凋亡诱导作用。方法 应用四甲基偶氮唑盐（MTT法测定汉黄芩素对于SGC7901细胞增殖活性;应用肿瘤细胞侵袭实验观察细胞侵袭能力;应用形态学方法、流式细胞仪测定汉黄芩素对SGC7901细胞的凋亡作用,进行细胞周期分析,并观察对胃癌细胞内活性氧（ROS的影响。结果 汉黄芩素对SGC7901细胞增殖和侵袭活性具有明显抑制作用,其抑制细胞增殖的IC₅₀为（74.26±1.21μmol·L-1,汉黄芩素也具有诱导胃癌细胞凋亡作用,荧光染色可见明显核碎裂、染色体聚集,并使胃癌细胞阻滞于G₀/G₁期;使肿瘤细胞内ROS水平明显升高。结论 汉黄芩素对胃癌SGC7901细胞的增殖有抑制及促进凋亡的作用,可能与上调细胞内ROS水平有关。     

UCP2:解偶联蛋白家族的新成员

解偶联蛋白 2 (uncouplingprotein 2 ,UCP2 )是解偶联蛋白家族的新成员 ,位于线粒体内膜上的阳离子载体蛋白。它可以引起质子的渗漏 ,使氧化磷酸化解偶联 ,ATP合成减少 ,能量以热的形式散失。UCP2 广泛分布于人体各组织器官。UCP2 主要参与能量代谢和脂代谢调节 ,但其广泛分布和轻微解偶联作用提示它的意义可能不仅限于此。目前UCP2 与氧化损伤的关系以及在脏器疾病中的作用已引起人们的关注。本文概述UCP2 的分布、作用及其表达调节。     

Blood-Brain Barrier Permeability of Asiaticoside,Madecassoside and Asiatic Acid in Porcine Brain Endothelial Cell Model

Neurotherapeutic potentials of Centella asiatica and its reputation to boost memory, prevent cognitive deficits and improve brain functions are widely acknowledged. The plant's bioactive compounds, i.e. asiaticoside, madecassoside and asiatic acid were reported to have central nervous system (CNS) actions, particularly in protecting the brain against neurodegenerative disorders. Hence, it is important for these compounds to cross the blood-brain barrier (BBB) to be clinically effective therapeutics. This study aimed to explore the capability of asiaticoside, madecassoside and asiatic acid to cross the BBB using in vitro BBB model from primary porcine brain endothelial cells (PBECs). Our findings showed that asiaticoside, madecassoside and asiatic acid are highly BBB permeable with apparent permeability (P_app) of 70.61 ± 6.60, 53.31 ± 12.55 and 50.94 ± 10.91 × 10^?6 cm/s respectively. No evidence of cytotoxicity and tight junction disruption of the PBECs were observed in the presence of these compounds. Asiatic acid showed cytoprotective effect towards the PBECs against oxidative stress. This study reported for the first time that Centella asiatica compounds demonstrated high capability to cross the BBB, comparable to central nervous system drugs, and therefore warrant further development as therapeutics for the treatment of neurodegenerative diseases.     

Identification of biomarkers for essential hypertension based on metabolomics

AimEssential hypertension (EH) is one of the most important public health problems worldwide. However, the pathogenesis of EH is unclear and early diagnostic methods are lacking. Metabolomics demonstrates great potential for biomarker discovery and the mechanistic exploration of metabolic diseases.Data synthesisThis review included human and animal metabolomics studies related to EH in the PubMed and Web of Science databases between February 1996 and May 2020. The study designs, EH standards, and reported metabolic biomarkers were systematically examined and compared. The pathway analysis was conducted through the online software MetaboAnalyst 4.0.Twenty-two human studies and fifteen animal studies were included in this systematic review. There were many frequently reported biomarkers with consistent trends (e.g., pyruvate, lactic acid, valine, and tryptophan) in human and animal studies, and thus had potential as biomarkers of EH. In addition, several shared metabolic pathways, including alanine, aspartate, and glutamate metabolism, aminoacyl-tRNA biosynthesis, and arginine biosynthesis, were identified in human and animal metabolomics studies. These biomarkers and pathways, closely related to insulin resistance, the inflammatory state, and impaired nitric oxide production, were demonstrated to contribute to EH development.ConclusionsThis study summarized valuable metabolic biomarkers and pathways that could offer opportunities for the early diagnosis or prediction of EH and the discovery of the metabolic mechanisms of EH.