满族新生儿血红蛋白F中G_γ／A_γ比值测定及其异常者γ－珠蛋白基因图谱分析

以聚丙烯酰胺凝胶电泳方法测定了３３１例辽宁满族新生儿脐带血血红蛋白Ｆ中Ｇγ／Ａγ比值。结果显示：高Ｇγ（＞８０％）者４例,占１．２１％,其基因频率（ｆ）为０．００６０４,低Ｇγ（３０－４８％）者６例,占１．８１％,其基因频率为０．００９０６,其余正常,Ｇγ平均值为６５．２３±６．３８％。未发现ＡγＴ链。对其中八例异常者（４例高Ｇγ值,４例低Ｇγ值）的染色体ＤＮＡ进行了基因图谱分析,确定４例高Ｇγ值者基因型有两种：Ｇγ－Ｇγ／Ｇγ－Ａγ二例,Ｇγ－ＡＧγ－Ａγ／Ｇγ－Ａγ二例;４例低Ｇγ值者基因型有二种,分别为：Ａγ－Ａγ／Ｇγ－Ａγ二例和－ＧＡγ／Ｇγ－Ａγ二例。其中Ａγ－Ａγ基因型在中国人群中未见报道过。     

稻米垩白形成的气象生态基础研究

在全国13个点、19个品种多播期试验基础上,对稻米垩自形成的气象生态基础进行了分析。结果表明,水稻齐穗后15天的日均温是影响稻米垩白大小的主要气象因子。经对稻米垩白与齐穗后15天内均温关系的动态分析可知,稻米垩白随该时段温度提高而增大的拐点温度约为29℃(品种间略有差异),接近或超过该点温度,稻米垩白会突发性地增加。     

基因组规模代谢网络模型构建及其应用

微生物制造产业的发展迫切需要进一步提高认识、设计和改造微生物细胞代谢的能力,以推动工业生物技术快速发展。随着微生物全基因组序列等高通量数据的不断积聚和生物信息学策略的持续涌现,使全局性、系统化地解析、设计、调控微生物生理代谢功能成为可能。而基于基因组序列注释和详细生化信息整合的基因组规模代谢网络模型(GSMM)构建为全局理解和理性调控微生物生理代谢功能提供了最佳平台。以下在详述GSMM的应用基础上,描述了如何构建一个高精确度的GSMM,并展望了未来的发展方向。     

油菜细胞质雄性不育系叶绿体DNA特异片段的分子克隆

采用高离子浓度缓冲液法分别提取油菜不育系及保持系的叶绿体DNA。经Sepharcse 4B柱层析纯化后,得到具有较高纯度的叶绿体DNA样品。将其分别用Eco RI、Bam HI、HimdHI、PstI和XhoI 5种限制性内切酶酶解,得到5种限制性内切酶图谱。其中除PstI图谱外,其它4种酶谱均显示出明显的两系间叶绿体DNA结构差异。以pBR 322为载体,分别克隆了不育系Bam HI图谱上的3个特异片段。得到的3个克隆,经克隆杂交及电泳分析后,证实分别带有上述3个目的片段。这些特异片段的特性及其与花粉育性的关系尚在研究中。     

Wangella harbinensis gen. nov., sp. nov., a new member of the family Micromonosporaceae

A novel endophytic actinomycete, designated strain NEAU-J3^T, was isolated from soybean root (Glycine max (L.) Merr) and characterized using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences suggested that strain NEAU-J3^T fell within the family Micromonosporaceae. The strain was observed to form an extensively branched substrate mycelium, which carried non-motile oval spores with a smooth surface. The cell walls of strain NEAU-J3^T were determined to contain meso-diaminopimelic acid and galactose, ribose and glucose were detected as whole-cell sugars. The major menaquinones were determined to be MK-9(H₄) and MK-9(H₆). The phospholipids detected were phosphatidylcholine and phosphatidylethanolamine. The major cellular fatty acids were determined to be C_16:0, C_18:1 ω9c, C_18:0, C_17:0, C_17:1 ω7c, anteiso-C_17:0, C_16:1 ω7c and C_15:0. The DNA G + C content was 62.5 mol%. On the basis of the morphological and chemotaxonomic characteristics, phylogenetic analysis and characteristic patterns of 16S rRNA gene signature nucleotides, strain NEAU-J3^T is considered to represent a novel species of a new genus within the family Micromonosporaceae, for which the name Wangella harbinensis gen. nov., sp. nov. is proposed. The type strain of Wangella harbinensis is strain NEAU-J3^T (=CGMCC 4.7039^T = DSM 45747^T).     

Diazoxide Pretreatment Prevents Aβ1–42 Induced Oxidative Stress in Cholinergic Neurons Via Alleviating NOX2 Expression

The aggregation and accumulation of amyloid-β (Aβ) plays a significant role in the pathogenesis of Alzheimer’s disease. Aβ is known to increase free radical production in neuronal cells, leading to oxidative stress and cell death. Diazoxide (DZ), a highly selective drug capable of opening mitochondrial ATP-sensitive potassium channels, has neuroprotective effects against neuronal cell death. However, the mechanism through which DZ protects cholinergic neurons against Aβ-induced oxidative injury is still unclear. The present study was designed to investigate the effects of DZ pretreatment against Aβ_1–42 induced oxidative damage and cytotoxicity. Through measures of DZ effects on Aβ_1–42 induced cellular damage, reactive oxygen species (ROS) and MDA generation and expressions of gp91phox and p47phox in cholinergic neurons, new insights into the neuroprotective mechanisms can be derived. Aβ_1–42 significantly decreased 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide levels and increased ROS and MDA production; all effects were attenuated by pretreatment with DZ or diphenyleneiodonium chloride (a NOX2 inhibitor). Pretreatment with DZ also attenuated the upregulation of NOX2 subunits (gp91phox and p47phox) induced by Aβ_1–42. Since NOX2 is one of the main sources of free radicals, these results suggest that DZ can counteract Aβ_1–42 induced oxidative stress and associated cell death by reducing the level of ROS and MDA, in part, by alleviating NOX2 expression.     

ESI-Q-TOF-MS直接进样法比较陕西五个不同地区丹参的化学成分差异（英文）

该研究采用ESI-Q-TOF-MS直接进样分析法对陕西商州、洛南、大荔、丹凤和铜川等五个地区丹参的化学成分进行了比较分析,通过丹参水溶性和脂溶性成分的质谱丰度差异评价了不同地区丹参化学成分含量的变化,对不同产地丹参的化学成分进行了鉴定,综合分析选出了最优的丹参种植产地。结果表明:五地丹参均含有丹参酮ⅡA、隐丹参酮、丹参酮Ⅰ、二氢丹参酮、丹参酚酮、次丹参醌、丹参醌Ⅱ等9种脂溶性化学成分和丹参素、咖啡酸、阿魏酸、迷迭香酸、原紫草酸、紫草酸、原儿茶醛、丹酚酸A、丹酚酸B等9种水溶性化学成分,其中丹参素钠、紫草酸、丹酚酸B和隐丹参酮的含量普遍较高,质谱丰度均大于30%。但是,随着种植环境不同,不同地区丹参的化学成分含量差异很大,如商州产丹参中含有较多具有生物活性的丹参酮类物质,其中丹参酮Ⅰ含量远远高于其他四个产地,质谱丰度达到72.6%,而其他地区丹参酮Ⅰ的质谱丰度为1.8%～11.3%。这表明丹参质量按照地区排序为商州>铜川>大荔>洛南>丹凤。该方法为中药药材质量评价提供了科学、可靠、便捷的途径,为药材规格等级的制定提供了新途径,为陕西丹参种植区域的选择提供了重要信息。     

Effects of dissolved organic matter from sewage sludge on the atrazine sorption by soils

The effects of dissolved organic matter (DOM), water soluble organic matter derived from sewage sludge, on the sorption of atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-trazine) by soils were studied using a batch equilibrium technique. Six paddy soils, chosen so as to have different organic carbon contents, were experimented in this investigation. Atrazine sorption isotherms on soils were described by the linear equation, and the distribution coefficients without DOM (Kd) or with DOM (Kd*) were obtained. Generally, the values of Kd*/Kd initially insoil-solution system form. Critical concentrations of DOM (DOMnp) were obtained where the value of Kd* was equal to Kd. The presence of DOM with concentrations lower than DOMnp promoted atrazine sorption on soils (Kd* ＞ Kd), whereas the presence of DOM with concentrations higher than DOMnp tended to inhibit atrazine sorption (Kd* ＜ Kd). Interestingly, DOMnp for tested soils was negatively correlated to the soil organic carbon content, and the maximum of Kd*/Kd (i.e.Kmax) correlated positively with the maximum of DOM sorption on soil (Xmax). Further investigations showed that the presence of hydrophobic fraction of DOM evidently promoted the atrazine sorption on soils, whereas the presence of hydrophilic DOM fraction obviously tended to inhibit the atrazine sorption. Interactions of soil surfaces with DOM and its fractions were suggested to be the major processes determining atrazine sorption on soils. The results of this work provide a reference to the agricultural use of organic amendment such as sewage sludge for improving the availability of atrazine in soils.     

Combinatorial signals of activin/nodal and bone morphogenic protein regulate the early lineage segregation of human embryonic stem cells

Cell fate commitment of pre-implantation blastocysts, to either the inner cell mass or trophoblast, is the first step in cell lineage segregation of the developing human embryo. However, the intercellular signals that control fate determination of these cells remain obscure. Human embryonic stem cells (hESCs) provide a unique model for studying human early embryonic development. We have previously shown that Activin/Nodal signaling contributes to maintaining pluripotency of hESCs, which are derivatives of the inner cell mass. Here we further demonstrate that the inhibition of Activin/Nodal signaling results in the loss of hESC pluripotency and trophoblast differentiation, similar to BMP4-induced trophoblast differentiation from hESCs. We also show that the trophoblast induction effect of BMP4 correlates with and depends on the inhibition of Activin/Nodal signaling. However, the activation of BMP signaling is still required for trophoblast differentiation when Activin/Nodal signaling is inhibited. These data reveal that the early lineage segregation of hESCs is determined by the combinatorial signals of Activin/Nodal and BMP.