Gambogic Acid Sensitizes Ovarian Cancer Cells to Doxorubicin Through ROS-Mediated Apoptosis

Ovarian cancer is one human malignancy which has response portly to doxorubicin. The anti-cancer activity of gambogic acid has been tested in in vitro and in vivo studies. In this study, we showed that gambogic acid, a natural compound, could potentiate the anticancer activity of doxorubicin in ovarian cancer through ROS-mediated apoptosis. Platinum-resistant human ovarian cancer cell line (SKOV-3) was treated with gambogic acid, doxorubicin, or the combination of both to investigate cell proliferation and apoptosis. We found that the combination of gambogic acid and doxorubicin causes synergistic loss of cell viability in SKOV-3 cells and this synergistic effect correlated with increased cellular ROS accumulation. Moreover, in vivo results showed that gambogic acid and doxorubicin combination resulted in a synergistic suppressing effect on tumor growth in ovarian cancer mice model. Taken together, the results suggested that doxorubicin in combination with gambogic acid might provide a promising therapeutic strategy to enhance chemosensitivity of ovarian cancer to doxorubicin.     

Minimization of aggregation of secreted bivalent anti-human T cell immunotoxin in Pichia pastoris bioreactor culture by optimizing culture conditions for protein secretion

In a bioreactor culture of genetically engineered Pichia pastoris secreting a bivalent immunotoxin, 64% of the secreted immunotoxin was present in aggregate forms and this resulted in a loss of bioactivity. Biochemical analyses of the secreted immunotoxin and an in vitro aggregation study using purified monomeric immunotoxin suggested that aggregation was primarily an extracellular event. By employing limited methanol feeding at 0.75 mlmin(-1) per 10l initial medium, oxygen consumption was reduced, permitting a lowering of the bioreactor agitation speed from 800 to 400 rpm. By increasing the anti-foam reagent to 0.6 mll(-1), the thickness of the air/liquid interfacial foam layer was reduced by 80%. These steps reduced the immunotoxin aggregates from 64% to 5%. Consequently immunotoxin purification yield was increased from 53.0% to 73.8%. Simultaneously this methodology enhanced immunotoxin secretion to 120 mgl(-1) at 163 h of methanol induction in a toxin resistant production strain. We conclude that minimizing shearing force and reducing the air/liquid interfacial foam area are crucial factors in reducing hydrophobic protein aggregation upon secretory expression in yeast bioreactor cultures.     

2 型糖尿病神经病变患者血清IL-6、8-iso-PGF2α 检测及意义

目的:探讨2型糖尿病神经病变(DPN)患者血清IL-6、8-iso-PGF2α水平的变化及意义。方法:选择2型糖尿病患者伴神经病变的患者55例,单纯2型糖尿病不伴有神经病变的患者25例,另选25例体检健康者作为对照组。采用ELISA法分别测定各组血清IL-6、8-iso-PGF2α水平。结果:血清IL-6、8-iso-PGF2α水平在糖尿病组和糖尿病神经病变组均较对照组显著升高,差异具有统计学意义(P<0.01)。DN组8-iso-PGF2α较DM组显著升高,差异具有统计学意义(P<0.05);但IL-6在两组间差异无统计学意义(P>0.05)。结论:IL-6在糖尿病神经病变发病中的作用不能肯定。8-iso-PGF2α可能通过氧化应激作用参与糖尿病神经病变的发生发展。     

植物细胞离析酶的制备和应用

用 Aspergillus sp．A-19菌经固体发酵研制成一种新的植物细胞离析酶(SeparatasezA—P)。其离析单细胞的酶活力平均为70 767u／g,有效作用的pH在3．0—7．0,温度为20—45℃。发酵培养基配方是麸皮：桔皮粉：(NH₄)₂SO₄(w／w)为100:100:O．63,料水比为1 :2．0,培养适宜条件为25℃、60小时。     

2000—2015年祁连山南坡生态系统服务价值时空变化

祁连山是我国西部重要的生态安全屏障和生物多样性保护优先区域,其中南坡地区是水源涵养服务核心区,但目前对该区域生态系统服务时空分布及动态变化仍缺乏深入认识。利用遥感技术和生态系统服务理论,综合多源数据产品,借鉴生态系统服务计算方法,对包括土壤保持等7个生态系统服务类型展开功能及价值核算,对祁连山南坡土壤保持等7个生态系统服务类型2000—2015年间的时空分异及动态展开监测和评估,研究表明:(1)近16年来祁连山南坡生态系统服务平均单位面积价值为76.27万元/km²,总价值为658.74亿元,且调节气候、水源涵养和调节空气质量服务构成了研究区生态系统服务的主体。(2)高寒草甸和高寒草原的生态系统服务总价值最高,而森林和灌丛的单位面积服务价值最高;天峻县和祁连县的生态系统服务总价值最高,而海晏县和刚察县的单位面积服务价值最高。(3)近16年来祁连山南坡生态系统服务价值呈增长趋势,其中调节气候和调节空气质量服务价值的增速最快,且增长区域主要集中在研究区北部祁连县和天峻县境内。(4)研究区东部山区、南部环湖区以及中部湿地区能够提供多项复合生态服务功能,应作为生态保护和管...     

福建三都澳游泳动物种类组成及群落结构稳定性

利用2012-2013年三都澳渔业资源的定置张网调查资料, 应用物种多样性指数、数量生物量比较曲线(ABC曲线)及鱼类分类多样性指数等方法分析三都澳游泳动物种类组成特征和群落结构的稳定性。调查中共出现游泳动物195种, 隶属于17目64科125属, 其中鱼类143种, 甲壳类47种, 头足类5种。大黄鱼(Larimichthys crocea)在三都澳4个航次的调查中都是最主要的优势种类, 其他优势种类还包括叫姑鱼(Johnius belengerii)、白姑鱼(Argyrosomus argentatus)、虾虎鱼类和一些甲壳类。大黄鱼多为养殖群体, 其他优势种类的共同特征是个体小, 繁殖周期短, 生物量季节或年际间波动剧烈。物种多样性分析表明, 三都澳游泳动物群落平均Shannon-Wiener多样性指数为2.61, 9、10月高, 1、5月低。ABC曲线分析表明, 4次调查中群落结构存在明显的变化, 繁殖群体的补充、个体生长、捕捞、伏季休渔等是影响群落结构稳定性的因素。本次研究表明, 大黄鱼生物量的比例与Shannon-Wiener多样性指数呈极显著负相关(P < 0.01, R = -0.890), 与种类数呈显著负相关(P < 0.05, R = -0.563)。结合近年来的调查数据, 统计得到三都澳的现存鱼类约224种, 其平均分类差异指数(△⁺)为59.5, 分类差异变异指数(∧⁺)为260.8。相对于中国沿海其他海域, 三都澳鱼类群落分类学范围较小, 且群落间的分类地位关系极不均匀, 群落抗干扰的能力较差。     

模拟微重力条件下大鼠肝细胞三维培养支架材料的筛选（简报）

组织工程是一门新兴的边缘学科,它是利用体外培养的人体功能细胞与适当的细胞外基质或支架材料相结合,然后将其移植到体内病损部位以期达到修复目的。微重力组织工程(Microgravity Tissue Engineering)是近年来由美国空间生物技术研究人员开创的一个独特研究领域,其核心技术是     

Phylogeny of parasitic parabasalia and free-living relatives inferred from conventional markers vs. Rpb1, a single-copy gene

Background

Parabasalia are single-celled eukaryotes (protists) that are mainly comprised of endosymbionts of termites and wood roaches, intestinal commensals, human or veterinary parasites, and free-living species. Phylogenetic comparisons of parabasalids are typically based upon morphological characters and 18S ribosomal RNA gene sequence data (rDNA), while biochemical or molecular studies of parabasalids are limited to a few axenically cultivable parasites. These previous analyses and other studies based on PCR amplification of duplicated protein-coding genes are unable to fully resolve the evolutionary relationships of parabasalids. As a result, genetic studies of Parabasalia lag behind other organisms.

Principal Findings

Comparing parabasalid EF1α, α-tubulin, enolase and MDH protein-coding genes with information from the Trichomonas vaginalis genome reveals difficulty in resolving the history of species or isolates apart from duplicated genes. A conserved single-copy gene encodes the largest subunit of RNA polymerase II (Rpb1) in T. vaginalis and other eukaryotes. Here we directly sequenced Rpb1 degenerate PCR products from 10 parabasalid genera, including several T. vaginalis isolates and avian isolates, and compared these data by phylogenetic analyses. Rpb1 genes from parabasalids, diplomonads, Parabodo, Diplonema and Percolomonas were all intronless, unlike intron-rich homologs in Naegleria, Jakoba and Malawimonas.

Conclusions/Significance

The phylogeny of Rpb1 from parasitic and free-living parabasalids, and conserved Rpb1 insertions, support Trichomonadea, Tritrichomonadea, and Hypotrichomonadea as monophyletic groups. These results are consistent with prior analyses of rDNA and GAPDH sequences and ultrastructural data. The Rpb1 phylogenetic tree also resolves species- and isolate-level relationships. These findings, together with the relative ease of Rpb1 isolation, make it an attractive tool for evaluating more extensive relationships within Parabasalia.     

原生质体技术选育桃红侧耳优良菌株

研究了桃红侧耳原生质体的制备及再生,并进行了原生质体再生株的筛选工作。实验表明,培养5天的桃红侧耳菌丝体30℃酶解3h原生质体数目可达8.4×107/mL。原生质体再生率在1号再生培养基上最高,为6.9%。再生菌株经筛选后,得到长速显著快于出发菌株的优良菌株H120和H247。经F3代栽培实验证明:H120和H247的生物学效率明显优于出发菌株,且差异极显著。酯酶同工酶分析表明:H120和H247酶谱均发生了变化。