Beta-carotene affects gene expression in lungs of male and female <Emphasis Type="Italic">Bcmo1</Emphasis><Superscript>−/−</Superscript> mice in opposite directions

Molecular mechanisms triggered by high dietary beta-carotene (BC) intake in lung are largely unknown. We performed microarray gene expression analysis on lung tissue of BC supplemented beta-carotene 15,15′-monooxygenase 1 knockout (Bcmo1 ^−/−) mice, which are—like humans—able to accumulate BC. Our main observation was that the genes were regulated in an opposite direction in male and female Bcmo1 ^−/− mice by BC. The steroid biosynthetic pathway was overrepresented in BC-supplemented male Bcmo1 ^−/− mice. Testosterone levels were higher after BC supplementation only in Bcmo1 ^−/− mice, which had, unlike wild-type (Bcmo1 ^+/+) mice, large variations. We hypothesize that BC possibly affects hormone synthesis or metabolism. Since sex hormones influence lung cancer risk, these data might contribute to an explanation for the previously found increased lung cancer risk after BC supplementation (ATBC and CARET studies). Moreover, effects of BC may depend on the presence of frequent human BCMO1 polymorphisms, since these effects were not found in wild-type mice.     

Protecting the boundary: the sentinel role of host defense peptides in the skin

The skin is our primary shield against microbial pathogens and has evolved innate and adaptive strategies to enhance immunity in response to injury or microbial insult. The study of antimicrobial peptide (AMP) production in mammalian skin has revealed several of the elegant strategies that AMPs use to prevent infection. AMPs are inducible by both infection and injury and protect the host by directly killing pathogens and/or acting as multifunctional effector molecules that trigger cellular responses to aid in the anti-infective and repair response. Depending on the specific AMP, these molecules can influence cytokine production, cell migration, cell proliferation, differentiation, angiogenesis and wound healing. Abnormal production of AMPs has been associated with the pathogenesis of several cutaneous diseases and plays a role in determining a patient’s susceptibility to pathogens. This review will discuss current research on the regulation and function of AMPs in the skin and in skin disorders.     

法锥条件下非凸规划的非内点同伦方法

利用不可行的内点同伦方法(CHIIP)求解非凸规划问题的KKT点. 证明了当非凸规划问题的可行域满足法锥条件时, 跟踪同伦方程产生的同伦曲线可得到非凸规划问题的KKT点, 且该算法具有全局收敛性.     

混合约束非凸规划拟锥条件下的同伦方法

使用同伦算法研究混合约束的非凸非线性规划问题. 当规划问题为混合约束（带有等式约束）时, 可行域变成一个边界区域, 并没有内点. 通过对可行域定义新的拟锥条件, 给出相应同伦方程, 并证明此同伦算法在此拟锥条件下具有全局收敛性.     

东濮凹陷胡庆地区原油地球化学特征与油源分析

研究东濮凹陷胡庆地区原油地球化学特征及其来源.利用有机地球化学分析方法,对原油与烃源岩进行饱和烃色谱、饱和烃与芳烃色谱-质谱分析,剖析了两者的分子地球化学特征及油源.研究表明:胡庆地区发育3类原油,第一类原油具有极高伽马蜡烷,质量色谱图中甾烷呈"L"形特征,来自第二台阶的沙一段烃源岩,在沙一段储层中富集形成自生自储常温...     

湘西更新世哺乳动物化石痕迹考察研究

目的 考察湘西土家族苗族自治州古丈县断龙乡猛虎洞更新世哺乳动物群骨化石断裂痕迹的状态与原因,探索湘西地区古人类活动的遗迹.方法 观测哺乳动物群骨化石断裂痕迹剖面的形态结构,以区别食肉类动物群的咬痕与人类打造的印迹.结果 经40件东方剑齿象、中国犀、鹿等残骨化石标本断裂痕迹剖面的观测,发现有部分骨化石断裂剖面圆钝,似啮齿动物的咬痕,但大部分骨化石断端剖面呈锥形切削改造,有的双面削刮呈锐利器型,有的存在明显打击或铲刮的 “印记”,初步认为属早期人类制作骨器的遗迹.结论 结合地理环境和地学结构分析,猛虎洞可能属晚更新世(10～5)万年前旧石器人类穴居的营地或系同生代古脊椎动物的遗址.     

职住变迁与通勤自平衡

采用2011年和2014年各两周的上海移动手机信令数据,通过跟踪分析识别出居住地、就业地发生变迁的居民作为研究对象,数据可视化、描述性统计、定量对比分析等方法对同一批变迁居民的通勤行为进行跟踪研究,以此对其中存在的“自平衡”特征进行分析,并进一步研究该变化特征与城市空间之间所存在的联系。研究表明：总体层面,从平均通勤距离变化以及过剩通勤率变化方面来看,居民在进行居住地、就业地变迁时均存在通勤“自平衡”的特征与趋势;个体层面,原通勤距离越远,通过居住地、就业地变迁以改善自身通勤关系追求通勤“自平衡”的效果越明显;就业地变迁居民的通勤“自平衡”特征相较于居住地变迁来说更加显著;空间集合层面,职住关系较差的居住区、就业区,存在总体的“自平衡”现象。     

碱激发胶凝材料的碳化性能研究进展

碱激发胶凝材料作为新型绿色建筑材料,在促进工业固体废料的循环使用、减少CO2气体排放等方面有着突出的优势,近几年针对这种材料耐久性能的研究越发受到重视,碳化作为影响耐久性能的关键因素,也需要进一步的研究。从碳化机理、碳化速率、碳化影响以及抗碳化性能改善方面总结了碱激发胶凝材料碳化性能研究现状,概述了目前碳化领域研究所取得的成果和面临的困难。基于已有成果,提出了研究建议,以期为碱激发混凝土的发展和推广应用提供参考。     

Effects of Hydrophilic Monomer Types and Level on Polystyrene-Acrylate/montmorillonite Nanocomposite Made by Emulsion Polymerization

1 Results Nanocomposite has attracted more and more interest all over the world.Polystyrene (PS) is a commercialized and mass-productive polymer,continuous research efforts have been devoted to the development of polystyrene/montmorillonite (PS/MMT) nanocomposites[1-2].But the polarity of styrene (St) is too small to intercalate the space between the clay layers.The polarity of hydrophilic monomer is so strong that it can intercalate the MMT easily,the intercalated smectic clays maybe exfoliated by usin...     

HCV全长cDNA细胞培养适应性突变体的构建及其体外转录制备感染性RNA的研究

运用重叠延伸PCR方法对HCV全长基因组cDNANS3和NS5A上的E1202G、T1280I和S2197P进行细胞培养适应性突变,构建含有细胞培养适应性突变的HCV全长基因组cDNA,体外转录制备RNA,脂质体法转染人肝癌细胞Huh-7,以RT-PCR检测HCV正、负链RNA,间接免疫荧光法和Western blot检测细胞内HCVNS3蛋白的表达。结果证明,转染后细胞内可间断检测到HCV正、负链RNA及HCVNS3蛋白的表达,且突变体RNA与未突变的HCVRNA相比,明显具有更高的复制效率和蛋白表达。该研究为后续HCV体外培养体系的研究提供了可在细胞内高效自主复制的HCV病毒模板。