基于细胞色素b基因的大河乌猪群体遗传结构研究

为了弄清大河乌猪群体遗传分化水平和遗传结构,以曲靖市5个地理种群的46个大河乌猪样品为试验材料,采用分子生物学方法测定和分析所有个体的线粒体细胞色素b(Cyt b)基因DNA序列。分子变异分析结果表明,大河乌猪群体遗传变异主要来自种群内(62.63％),说明该物种群体遗传结构不明显。中性检验结果进一步证实,大河乌猪群体曾发生过种群数量扩张。这种不显著的种群结构主要来自于大规模的引种和扩大繁育,致使各地理种群间的遗传趋同和遗传一致性。研究结果有望为大河乌猪分子遗传选育工作提供重要的基础数据,并为其遗传种质资源的保护提供重要参考。     

Dexmedetomidine attenuates acute alcoholic hepatic injury in mice

AIM: To investigate the effects of dexmedetomidine (DEX) on acute alcoholic hepatic injury in mice and to explore the possible mechanisms. METHODS: Kunming mice (n=50) were randomly divided into 5 groups (n=10): normal saline control (NS) group, acute alcoholic hepatic injury model (E) group, low-dose (10 μg/kg) DEX (E+L) group, medium-dose (50 μg/kg) DEX (E+M) group and high-dose (100 μg/kg) DEX (E+H) group. The animals were sacrificed at 6 h after gavage of alcohol or normal saline. The levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TG), malondialdehyde (MDA), glutathione (GSH) and superoxide dismutase (SOD) were measured. The livers were removed for evaluation of histological characteristics and determining the content of tumor necrosis factor-α (TNF-α) amd interleukin-1β (IL-1β) in the liver tissues by ELISA. The expression levels of cytochrome P450 2E1 (CYP2E1) and nuclear factor-κB (NF-κB) in the liver tissues were evaluated by Western blot. RESULTS: Compared with NS group, the levels of ALT, AST and TG were obviously increased in E group, which were obviously decreased in E+M and E+H groups. Compared with NS group, the levels of TNF-α, IL-1β and MDA were obviously increase in E group, which were obviously decreased in E+M and E+H groups. Compared with NS group, the activity of SOD and the content of GSH were obviously decreased in E group, which were obviously increased in E+M and E+H groups. Compared with NS group, the expression of CYP2E1 and NF-κB was obviously increase in E group, which was obviously decreased in E+M and E+H groups. Compared with NS group, ethanol induced marked liver histological injury, which was less pronounced in E+M and E+H groups. CONCLUSION: DEX has a protective effect on mouse liver with acute alcoholic injury by the involvement in the processes of antioxidation and antiinflammation, and its mechanism may be associated with the inhibition of CYP2E1 and NF-κB expression.     

天山天池二倍体棱叶蒜的开花动态及交配系统

以分布于新疆天山天池的二倍体棱叶蒜(Allium caeruleum)为研究对象,观察记录了开花进程,测定其花粉活力和柱头可授性,并采用去雄、套袋、人工授粉等方法对其交配系统进行检测。结果表明:(1)伞形花序平均直径为(29.07±1.17)mm,花被片天蓝色,花期6—8月;两性花,平均小花数205.67±19.88个,密集,无株芽;小花开放历经弹头、张口、吐药、展开、抱合和萎蔫等过程,历时5~7 d;小花开放进程中花药和柱头间存在空间隔离,从第1枚花药伸出至6枚花药全部脱落以及柱头伸长至萎蔫各需要2~3 d;阴天比晴天分别延长散粉以及延迟柱头萎蔫0.5~1 d。棱叶蒜具有雄蕊先熟、雌雄异熟、雌雄异位以及吸引昆虫避免自交的花部特征。(2)花药开裂散粉4 h时花粉活力最强(79.23%±1.97%的花粉具有活力),36 h后降至很低,属于短寿命花粉。(3)联苯胺—过氧化氢和MTT法检测柱头可授性;花丝、花柱等长期部分柱头开始具有可授性,花丝、花柱合拢期至花丝萎蔫期柱头可授性最强。同一朵花雄蕊和雌蕊的可育期存在部分时间重叠,防止了杂交失败。(4)单花花粉量为31 275±3 651,胚珠数6,P/O值为5 212±608;杂交指数OCI为5;无自发的自花传粉现象,不存在风媒传粉和无融合生殖;倾向于异交为主、自交可育,具备兼性异交并需要传粉媒介的混合交配系统的特征。天山天池二倍体棱叶蒜还以种子休眠、鳞芽无性繁殖的生殖补偿方式保证特殊地理环境下的种群繁衍。     

茭白黑粉菌不同培养形态及能谱分析

将茭白灰茭内的黑粉菌厚垣孢子放置在PSA培养基上培养,结果表明:茭白黑粉菌能够在PSA培养基上完成其生活史,但形成菌丝体及厚垣孢子需要较长的时间;X-EDS分析发现不同培养形态之间的原子比值存在差异,其中采集的与培养的厚垣孢子差异明显.     

Over-expression of P21 attenuates cisplatin-induced HK-2 cells injury

AIM:To investigate the effect of P21 on cisplatin-induced renal tubular epithelial cells injury.METHODS:The expression of P21 at mRNA and protein levels in cisplatin treated human renal tubular epithelial cells (HK-2) cells was determined by RT-qPCR and Western blot. Over-expression of P21in the HK-2 cells was induced by the transfection of pcDNA3-P21. The cell viability and cell apoptosis were detected by CCK-8 assay and flow cytometry, respectively. Furthermore, the protein expression of kidney injury molecule-1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL), caspase-3, glucose-regulated protein 78 (GRP78) and CCAAT/enhancer-binding protein homologous protein (CHOP), and phosphorylation level of eucaryotic translation initiation factor 2α (eIF2α) and protein kinase R-like endoplasmic reticulum kinase (PERK) were detected by Western blot.RESULTS:Cisplatin increased the mRNA and protein levels of P21 in a time-and concentration-dependent manner in the HK-2 cells. Over-expression of P21 inhibited cisplatin-induced cell apoptosis, and down-regulated the expression of KIM-1 and NGAL. Furthermore, Over-expression of P21 decreased the protein levels of GRP78, p-PERK, p-eIF2α, CHOP and cleaved caspase-3.CONCLUSION:Over-expression of P21 attenuates cisplatin-induced HK-2 cells injury, and the mechanism may be related to the modulation of endoplasmic reticulum stress pathway and inhibition of cell apoptosis.     

Epoxyeicosatrienoic acid: the signal transduction

Cytochrome P450 monoxygenase converts arachionic acid to four epoxyeicosatrienoic acid regiosomes: 5, 6-EET (epoxyeicosatrienoic acid); 8, 9-EET; 11, 12-EET and 14, 15-EET. Recent studies show that EETs are involved in signal transduction. EETs open Ca²⁺-sensit ive K⁺ channel and inhibit Na⁺ channel, Ca²⁺-sensitive Cl^- channel and so on. What is more, EETs have been demonstrated to activate PP60^c-src and initiate a tyrosine kinase cascade that mediates mitogenic effects.     

美洲黑杨×青杨杂种无性系引种育苗试验

以陕林4号为对照,按照随机区组设计方法对引进的美洲黑杨×青杨4个杂种无性系的苗木生长量和抗病虫能力等指标进行了调查研究.结果表明,93-8-17号无性系苗木生长快,抗病虫能力强.1 a生苗年平均高生长量为3.82 m,比无性系93-8-18、93-8-6和93-8-20分别高7.9,13.4和15.1,比陕林4号小2.6;地径生长量为2.32 cm,比93-8-18、93-8-6和93-8-20分别大7.4,11.0和16.6,比对照陕林4号大12.6.2 a平均受害指数为l5.6,与对照品种相当,是引进     

伊通河流域农业非点源污染对水环境的影响模拟研究

针对伊通河流域的农业非点源污染问题,在GIS技术和流域基础数据库的支持下,采用SWAT模型建立了该区农业非点源污染模型.对研究区农药化肥中的氮、磷元素,泥沙的时空分布状况及总氮进入地下水的状况进行了模拟研究.模拟结果表明该模型精度满足要求.通过模型模拟计算,泥沙的输出量1985及2008年分别为7.04×106和3.46×106 t.1985年总氮和总磷的输出量分别为20 400和2 300 t;2008年的输出量分别为1985年的1/2.6,7,8这3个月污染物质输出所占比例较大,约占全年的90％.同时模拟结果还显示,通过渗透进入地下水的氮量不能被忽视,1985年和2008年通过下渗进入到地下水中的氮量约为当年其他形式输出量的2.4和5.5倍.     

几种粉煤灰的特性及其硅、磷的农业化学行为研究

 对采自湖南省的几种粉煤灰特性及其硅、磷农业化学行为的研究结果表明，粉煤灰颗粒组成以砂粒（1～0.05 mm）和粗粉粒（0.05～0.01 mm）为主，平均分别占34.37 % 和38.56 %。容重较小，仅为土壤的1/2~1/3，除采自长沙电厂的粉煤灰外，pH一般大于10.0，可以用作粘质酸性土壤改良剂。粉煤灰水溶性硅和有效硅含量与土壤相差不明显，不能把粉煤灰直接作硅肥使用。粉煤灰的全钾含量和土壤大致相同，但其游离态铁比土壤低3 ~ 4倍。粉煤灰中硅的释放量随时间变化的关系可以用Elovich方程和Freundlich方程进行较好的描述，其相应的参数b和k反映了硅的释放能力，b、k值越大，硅释放能力越强。不同来源粉煤灰的b、k值不同，其大小顺序为：湘潭电厂(1539.3，2139.3)、岳阳纸厂(1602.4，1274.0)＞华能电厂(1325.7，1181.6)＞长沙电厂(1250.6，915.9)＞洞庭氮肥厂(751.9，565.6)＞株洲电厂(555.5，454.4)；粉煤灰中硅在100 h内释放量比土壤高3.0~25.0倍，能为作物提供一定数量的硅营养，故可把粉煤灰作为一种硅肥添加剂，其中以湘潭电厂和岳阳纸厂的粉煤灰为好。粉煤灰的全磷含量和有效磷含量一般比土壤高，它对磷的吸附量随着加入溶液磷的浓度的增加而增加，但其吸附率随着加入溶液磷的浓度的增加而减少；粉煤灰的吸磷率比土壤高，但其解吸率低。Langmuir方程、Freundlich方程和Temkin方程都能很好地拟合粉煤灰对磷的吸附，其相应的参数Xm、a和k2都可以表征粉煤灰对磷的吸附能力。粉煤灰对磷的吸附主要是专性吸附和化学沉淀反应，所以在施用粉煤灰改良土壤或利用粉煤灰作添加剂制造复混肥时，必须考虑粉煤灰对磷的固定作用。     

低磷条件下不同磷效率小麦品种及其杂种F1光合碳同化特性研究

以典型的磷低效(L)、吸收高效(H1)和利用高效(H2)的小麦品种及以上述品种为亲本配制的杂种F1-1(L×H1)和F1-2(L×H2)为材料,对上述品种和杂种F1的光合特性及其生理机制进行了研究。结果表明,缺磷条件下,随着叶片生长进程,供试品种和杂种F1旗叶CO2传导参数气孔导度(Gs)、叶肉导度(Gm)和碳酸酐酶(CA)活性;旗叶叶绿素含量(Chl)、光合速率(Pn)、叶绿体无机磷(PI)浓度和Mg2+-ATPase活性、可溶蛋白含量(SP)和RuBPCase活性均不断降低。不同磷效率类型品种相比,旗叶各测定时期上述参数均以L较低,H1和H2较高。与各自亲本相比,F1-1和F1-2各测定时期的光合生理参数多表现出明显的优势。表明磷高效小麦品种(H1和H2)以及杂种叶片光合碳同化特性的相对提高,是由于其光合器官捕获光能的能力较强、光合作用气孔限制和非气孔限制的程度较低和暗反应速率较高综合作用的结果。其中,磷高效品种及杂种F1叶绿体Pi供应量的增多,在维持光合器官的结构和功能中可能具有重要作用。研究还表明,供试不同磷高效小麦品种之间(吸收高效H1和利用高效H2)尽管在磷的吸收和利用特征上表现明显不同,但在叶片的光合碳同化特性及其内在生理机制上表现相似,表明控制小麦磷素吸收与利用的遗传基因位点可能与控制光合器官结构与功能的遗传位点不存在紧密连锁。在低磷胁迫条件下,充分利用杂种F1在光合碳同化特性上的杂种优势,对于改善小麦对磷素的吸收和利用以及促进子粒产量的增加具有潜在的应用价值。