Human adipose tissue is a source of multipotent stem cells

Much of the work conducted on adult stem cells has focused on mesenchymal stem cells (MSCs) found within the bone marrow stroma. Adipose tissue, like bone marrow, is derived from the embryonic mesenchyme and contains a stroma that is easily isolated. Preliminary studies have recently identified a putative stem cell population within the adipose stromal compartment. This cell population, termed processed lipoaspirate (PLA) cells, can be isolated from human lipoaspirates and, like MSCs, differentiate toward the osteogenic, adipogenic, myogenic, and chondrogenic lineages. To confirm whether adipose tissue contains stem cells, the PLA population and multiple clonal isolates were analyzed using several molecular and biochemical approaches. PLA cells expressed multiple CD marker antigens similar to those observed on MSCs. Mesodermal lineage induction of PLA cells and clones resulted in the expression of multiple lineage-specific genes and proteins. Furthermore, biochemical analysis also confirmed lineage-specific activity. In addition to mesodermal capacity, PLA cells and clones differentiated into putative neurogenic cells, exhibiting a neuronal-like morphology and expressing several proteins consistent with the neuronal phenotype. Finally, PLA cells exhibited unique characteristics distinct from those seen in MSCs, including differences in CD marker profile and gene expression.     

Purification of human chorionic gonadotrophin from urine by membrane filtration affinity chromatography with a positively charged membrane.

A new method of affinity chromatography, termed membrane filtration affinity chromatography (MFAC), has been developed and applied to purify HCG from urine. By filtrating urine through ZBM (HCG in urine would bind to the antibody on ZBM) and by dissociating the HCG from the antibody on ZBM in purified form, we developed the MFAC and purified HCG from urine of pregnant women by MFAC. The purified HCG showed a single band in polyacrylamide gel electrophoresis. ZBM (1 cm(2)) could harvest 90.3 microg HCG, which showed immunoactivity of 8554 IU/mg. The rate of recovery was 87%. CONCLUSION: MFAC with ZBM is an effective method, which is much easier and cheaper than conventional affinity chromatography for purification of proteins from solution, especially from highly diluted solution.     

Impacts of fish aggregation devices on size structures of skipjack tuna Katsuwonus pelamis

Tuna purse seine fisheries target fish aggregated in schools, including free schools that are formed naturally based on fish biology and aggregations associated with natural and/or artificial drifting objects. Using data collected from skipjack tuna (Katsuwonus pelamis) fisheries, we evaluated differences in size structures between drifting-floating-object-associated schools and unassociated schools. We developed a generalized linear model to remove impacts of environmental variables on skipjack size composition. This study indicates that the drifting-floating-object-associated schools tended to have significantly wider size ranges than the unassociated schools. This suggests that unassociated schools were likely formed based on similarity in sizes among individuals within a school while drifting-floating-object-associated schools were probably composed of individuals of large size ranges and their formation was not based on the “size selection” rule. We concluded that the unassociated schools and the drifting-floating-object-associated schools were formed through different mechanisms, and drifting floating objects could aggregate unassociated schools of different size structures. Thus, a large scale of deployment of man-made floating objects might disrupt the spatial aggregation pattern of fish that otherwise tended to school based on their sizes in the absence of floating objects.     

贵州六盘水发现东阳江麝鼩

在贵州省六盘水市杨梅乡慕尼克村,利用陷阱法捕捉到3号麝鼩属(Crocidura)标本。本次采集标本的体形较小,头体长(49.0 ± 0.8)mm,尾长[(41.8 ± 4.2)mm]略短于头体长(尾长/头体长为85%)。背毛呈浅灰褐色,腹毛颜色浅于背毛,呈灰色。尾部双色,背侧黑褐色,腹侧淡于背侧。前足背部白色,后足则为淡灰色。尾近乎裸露,尾基约1/3着生稀疏白色长毛。颅全长(15.92 ± 0.55)mm,脑颅高(4.75 ± 0.18)mm。上门齿1枚,有一长而大的前尖和一小而矮的后尖。上单尖齿3枚,第1单尖齿最大,第2单尖齿略大于第3单尖齿,1枚第四前臼齿(P4),3枚臼齿。上述特征与东阳江麝鼩(C. dongyangjiangensis)模式标本的描述和鉴定特征基本一致,因此将3号采集标本鉴定为东阳江麝鼩。基于Cyt b基因进行分子系统发育分析,采集标本与麝鼩属物种中的东阳江麝鼩遗传距离最近,在0.004 ~ 0.027之间。系统发生树显示,3号标本与东阳江麝鼩构成一个单系进化分支,进一步证实本次采集的3号标本是东阳江麝鼩,为贵州省分布新记录种。     

Mechanisms of chromatin-based epigenetic inheritance

Multi-cellular organisms such as humans contain hundreds of cell types that share the same genetic information(DNA sequences), and yet have different cellular traits and functions. While how genetic information is passed through generations has been extensively characterized, it remains largely obscure how epigenetic information encoded by chromatin regulates the passage of certain traits, gene expression states and cell identity during mitotic cell divisions, and even through meiosis. In this r...     

串叶松香草的核型研究

串叶松香草Silphiura perfoliatum L.系菊科(Compositae)松香草属(SilphiumL.)多年生宿根草本植物,原产北美洲。1979年由中国科学院植物研究所北京植物园首次从朝鲜引进我国,1980年引种我所栽培,通过几年的试验观察表明:串叶松香草是一种高产、质优、适应性强的饲料作物,近年来,我省广泛发展和应用。据文献报     

布氏鲳鲹GHRH基因克隆、组织和胚胎表达模式

促生长激素释放激素(growth hormone releasing hormone, GHRH)主要生物学功能是刺激垂体细胞分泌生长激素,已被证实是动物体生长轴的重要调控因子之一,布氏鲳鲹是一种生长快速的海洋鱼类,为了揭示其代谢旺盛的调节机制,本研究从GHRH入手,利用RACE技术和qPCR方法对布氏鲳鲹GHRH基因进行了克隆、组织和胚胎表达模式研究。实验结果显示,布氏鲳鲹GHRH基因cDNA序列全长1019bp,5’UTR、3’UTR长度分别为327 bp和164 bp,开放阅读框528 bp,共编码175个氨基酸;同源性分析结果表明,布氏鲳鲹GHRH基因与其它鲈形目鱼类的同源性在91%以上。布氏鲳鲹GHRH基因的表达区域大多都集中在中枢系统,其中下丘脑表达量最高;GHRH在受精卵期到后续发育过程中均检测到表达,其表达水平在仔鱼期达到最高。序列分析、组织及胚胎表达的结果表明,布氏鲳鲹GHRH的调节模式仍然可能通过下丘脑调节垂体释放GH,GHRH在个体发育的较早阶段即开始发挥作用。本研究掌握了布氏鲳鲹GHRH基因的基本规律,为进一步研究生长轴的调控提供了理论参考。     

阿维链霉菌Streptomyces avermitilis碱性脂肪酶LpsA2的表达和酶学性质分析

【目的】本研究将推测的阿维链霉菌(Streptomyces avermitilis)脂肪酶基因lpsA2在大肠杆菌(Escherichia coli)中进行异源表达及系统的酶学性质分析。【方法】提取阿维链霉菌基因组,设计特异性引物,PCR扩增脂肪酶基因lpsA2,使其在大肠杆菌中异源表达,利用6个组氨酸标签纯化脂肪酶LpsA2,并进行酶学性质分析;对LpsA2进行序列比对和进化分析。【结果】氨基酸序列比对显示LpsA2具有脂肪酶典型的由Ser、His和Asp构成的活性部位,即Ser130-Asp221-His25,其中Ser位于保守的五肽结构(Gly128-His129-Ser130-Gln131-Gly132)中;分子系统学分析显示,LpsA2是脂肪酶第一家族亚家族成员(Subfamily I.7);实验测得纯化的重组脂肪酶LpsA2的最适反应pH为8.0,最适反应温度为50℃;最适底物为对硝基苯酚豆蔻酸酯;在10℃-50℃范围内该酶的激活自由能为6.3 kcal/mol;1 mmol/L Co2+、Hg2+、Zn2+可使酶活性提高至250%以上;15%的二甲基甲酰胺和二甲基亚砜使酶活分别提高至110.7%和138%;0.1%和1%的Span-20可使酶活性分别提高至352.7%和189.7%。【结论】本研究对推测的来源于S.avermitilis的脂肪酶基因lpsA2进行了异源表达和酶学功能鉴定,不仅为脂肪酶的研究积累了更多数据,也为具有优良性能的脂肪酶生物工程菌的筛选奠定了基础,更为其在食品加工、药物合成等工业生产中的应用提供了依据。     

宁夏野生维管植物编目

物种编目是区系研究、生物多样性监测和珍稀濒危生物保护的基础。宁夏维管植物编目对该区植物多样性保护和资源植物开发利用具有重要意义。本文在《宁夏植物志(第二版)》的基础上, 结合多年野外实地调查数据和相关文献资料, 按照APG Ⅳ分类系统修订了宁夏野生维管植物名录。结果显示: 宁夏有野生维管植物127科597属1,754种, 排名前10的优势科分别是菊科、禾本科、豆科、蔷薇科、毛茛科、苋科、唇形科、莎草科、石竹科和伞形科, 这10科共有物种939种, 占宁夏野生维管植物总数的53.53%; 科的组成以物种数小于20种的科为主, 属主要以小于5种的属为主; 2007年至今累计发现新记录植物230种; 宁夏有珍稀濒危植物25科44属65种; 外来归化、逸生及入侵植物9科22属28种。就国土面积和地理位置而言, 宁夏野生维管植物较为丰富。本研究结果可为《宁夏植物志(第三版)》修订和生物多样性监测与保护提供基础数据。