木荷及其与无患子皂甙抽提物单复配体外抗稻瘟病活性(英文)

来自木荷叶和无患子中果皮的皂甙抽提物对抗稻瘟病原活性被试验。皂甙抽提物体外抑制活性显示了皂甙剂量与抗真菌效果高度相关性。它们的抗稻瘟有效中浓度EC50:木荷叶乙醇抽提物为42.95μg/mL,木荷叶水抽提物为452.91μg/mL,无患子中果皮的甲醇抽提物为95.65μg/mL。一个重要的结果是当上述木荷叶和无患子中果皮醇抽提物以3∶4到15∶8的质量配比时产生了显著的增效抗稻瘟作用,而在其它配比时有相加作用。通过乙醚/丙酮沉析、硅胶柱色谱分离,以及酸水解和薄层过程,检测出木荷抽提物皂甙中含有2种三萜类皂甙元和5种单糖。纯化后的皂甙在150μg/mL时显示了98.28%的抑制率。此研究结果表明:木荷叶抽提物,或木荷叶和无患子中果皮抽提复配物对毁灭性的稻瘟病害具有重要地抗病效果。     

A（H1N1）疫苗免疫的血清中和抗体的交叉免疫反应分析

目的分析接种A（H1N1）疫苗人群血清的中和抗体对2009年A（H1N1）的抗病毒作用和相关病毒的交叉免疫保护作用。方法利用MDCK细胞的细胞病变检测接种A（H1N1）疫苗的人血清和未免疫的对照血清对甲型流感病毒A/Brisbane/10/2007（H3N2）,A/Brisbane/59/2007（H1N1）,A/California/07/2009（H1N1）和A/Shenzhen/406H/2006（H5N1）等病毒的中和作用。结果通过细胞病变观察,证实接种A（H1N1）疫苗的人血清稀释度为1∶40时,30份免疫血清可以中和H3N2（Brisbane）,H1N1（Brisbane）和H1N1（CA7）而不产生细胞病变,中和保护率分别均为100%,而相同稀释度的未免疫对照血清的中和保护率分别为100%,100%,40%;而当稀释度为1∶400时,30份免疫血清分别有13,20和21例未出现细胞病变,中和保护率分别为43%,67%,70%,10份对照血清的中和保护率分别为80%,70%,0%。两种稀释度的免疫血清和未免疫对照血清均不能中和H5N1引起细胞病变,中和保护率均为0%。结论接种2009年A（H1N1）疫苗可以诱导能中和CA7 H1N1的抗体产生,但该中和抗体对H3N2（Brisbane）,H1N1（Brisbane）,H5N1（SZ）高致病禽流感病毒等甲型流感病毒无交叉保护作用。     

板蓝根颗粒对甲型流感病毒小鼠的作用

目的测定板蓝根颗粒抗流感病毒的药效作用。方法 A/California/7/2009（CA7）病毒滴鼻感染BALB/c小鼠观察14d,观察板蓝根对甲型H1N1流感病毒感染小鼠的保护作用,计算小鼠存活率、存活天数以及延长生命率。感染的小鼠第5天每组小鼠处死一半,取肺组织,观察板蓝根对甲型H1N1流感病毒感染小鼠肺组织的保护作用。结果板蓝根可明显延长甲型H1N1流感病毒感染小鼠的存活天数并提高存活率,病理结果显示板蓝根对甲型H1N1流感病毒感染的小鼠的肺组织有一定程度的保护作用,与模型组比较差异显著（P〈0.05）。结论板蓝根颗粒对甲型H1N1流感病毒感染的小鼠有较好的保护作用。     

幽门螺杆菌L型感染及血管生成素的表达与胃癌血管生成的关系

目的探讨幽门螺杆菌L型(Hp-L)感染和血管生成素(Ang)在胃癌中的表达及与肿瘤血管生成的关系。方法采用革兰染色和免疫组化方法检测84例胃癌和30例癌旁正常组织中Hp-L型感染,应用免疫组化方法检测Ang-1、Ang-2蛋白表达水平,计数微血管密度(MVD),结合临床病理因素进行分析。结果胃癌组织中Hp-L型感染率、Ang-2阳性表达率、MVD值明显高于正常组织(P0.05),胃癌中Hp-L型感染与肿瘤分化程度、侵袭深度、临床分期、淋巴结转移有关(P0.05),与Ang-2表达、MVD呈正相关。胃癌组织中Ang-2表达与肿瘤大小、侵袭深度、淋巴结转移有关(P0.05),与MVD呈正相关。Ang-1在胃癌中表达略低于对照组,但无统计学差异(P0.05),Ang-1表达与侵袭深度和MVD呈负相关。结果 胃癌Hp-L型感染在肿瘤血管生成中起重要作用,其机制与Ang-2表达上调,Ang-2/Ang-1比例失衡有关。     

中国学术期刊网络出版总库节点文献新疆驴脑组织尼帕病毒N基因片段的检测

目的检测新疆伊犁草原地区放养新疆驴的脑组织样本中尼帕病毒（Nipah Virus,NiV）核蛋白（N）基因片段,调查该地区放养新疆驴NiV感染流行状况。方法采用一步法实时荧光定量逆转录聚合酶链反应（one-step Real-Time FQ RT-PCR）对采自新疆伊犁地区草原放养且未接种NiV疫苗的65例新疆驴脑组织进行NiVN基因片段检测。结果新疆驴脑组织标本中未检出NiV N基因片段。结论目前尚无证据表明我国新疆伊犁地区新疆驴中存在NiV感染,提示该地区短时间内爆发该病毒感染可能性较小。     

灯盏花产黄酮内生放线菌筛选及产黄酮能力的初步研究

通过黄酮类物质特异颜色反应和可见分光光度法,筛选产黄酮的灯盏花内生放线菌,研究灯盏花产黄酮内生放线菌在PDA、高氏1号和淀粉3种培养基上的产黄酮能力。结果表明:59株灯盏花内生放线菌中,8株菌的镁粉+浓盐酸、氯化铝、浓氨水3种颜色反应均成阳性,能够产生黄酮。形态学观察初步鉴定这8株菌均为链霉菌属(Streptomyces)。3种培养基中,在PDA培养基上灯盏花产黄酮内生放线菌的菌丝体生物量、黄酮含量和产量较高。8株灯盏花产黄酮内生放线菌中,菌株RA′1-7生长较好,菌株ELA′3-2和RA2-1菌丝体黄酮含量较高,菌株ELA′3-2菌丝体黄酮产量较高。     

湖南小溪国家级自然保护区野生观赏植物资源初步研究

实地调查了小溪国家级自然保护区内的野生观赏植物资源的种类、生活习性、利用价值及现状。结果表明,小溪自然保护区的野生观赏植物资源十分丰富,有81科171属519种及变种。蔷薇科、菊科等10科植物含有10种以上的植物,为该区的优势类群。对其中具有一定代表性、开发利用潜力较大的40种植物的生活型及供观赏的主要特征、花(果)期、生境、其他用途等进行了扼要描述。就如何充分合理地开发和保护野生观赏资源提出了建议。     

Single Amino Acid Alteration between Valine and Isoleucine Determines the Distinct Pyrabactin Selectivity by PYL1 and PYL2

Abscisic acid (ABA) is one of the most important phytohormones in plant. PYL proteins were identified to be ABA receptors in Arabidopsis thaliana. Despite the remarkably high degree of sequence similarity, PYL1 and PYL2 exhibit distinct responses toward pyrabactin, an ABA agonist. PYL1 inhibits protein phosphatase type 2C upon binding of pyrabactin. In contrast, PYL2 appears relatively insensitive to this compound. The crystal structure of pyrabactin-bound PYL1 revealed that most of the PYL1 residues involved in pyrabactin binding are conserved, hence failing to explain the selectivity of pyrabactin for PYL1 over PYL2. To understand the molecular basis of pyrabactin selectivity, we determined the crystal structure of PYL2 in complex with pyrabactin at 1.64 Å resolution. Structural comparison and biochemical analyses demonstrated that one single amino acid alteration between a corresponding valine and isoleucine determines the distinct pyrabactin selectivity by PYL1 and PYL2. These characterizations provide an important clue to dissecting the redundancy of PYL proteins.     

Dopamine Promotes the Survival of Embryonic Striatal Cells: Involvement of Superoxide and Endogenous NADPH Oxidase

The dopaminergic system appears early in mammalian brain development, and a neurodevelopmental role for dopamine (DA) has been suggested. In the present study, we found that DA markedly promoted the survival of embryonic striatal cells in cultures. The failure of DA receptor antagonists to block this survival-promoting effect and the capability of S-apomorphine, which is devoid of DA receptor agonist activity but possesses antioxidative activity as R-apomorphine and DA, to completely mimic this effect suggested that DA receptor activation was not required in the survival-promoting effect elicited by DA, and its antioxidative activity might be involved. Moreover, it was found that mRNA of NADPH oxidase was expressed in the embryonic striatum. Furthermore, DPI or apocynin, NADPH oxidase inhibitors, promoted the survival of embryonic striatal cells. Addition of either DA or DPI into striatal cell cultures decreased the superoxide level. These results indicate that the mechanisms underlying the neuroprotective effects of DA were likely associated with its antioxidative activity. NADPH oxidase might contribute, at least in part, to ROS generation.