胆碱受体化合物对厚壳贻贝幼虫变态的调控作用

为研究胆碱受体在厚壳贻贝幼虫变态发育过程中的作用,通过药理学手段调查胆碱类神经递质乙酰胆碱、氯甲酰胆碱及其拮抗剂六甲双铵和阿托品对厚壳贻贝幼虫变态发育调控作用。结果显示:在24 h暴露实验中,氯甲酰胆碱在10-5~10-4mol/L浓度表现出诱导活性,乙酰胆碱则无诱导活性。在持续暴露实验中,氯甲酰胆碱在10-5~10-4mol/L浓度表现出诱导活性,乙酰胆碱在10-6~10-4mol/L浓度表现出诱导活性。在拮抗剂实验中,在10-4mol/L氯甲酰胆碱或10-4mol/L乙酰胆碱存在时,N型胆碱受体拮抗剂六甲双铵对厚壳贻贝幼虫的变态均无抑制效果,表明N型胆碱受体可能并不在幼虫的变态发育过程发挥主导作用。M型胆碱受体拮抗剂阿托品在10-4mol/L氯甲酰胆碱存在时表现出抑制作用,且测试液中幼虫的变态率降为0%,表明M型胆碱受体可能参与调控厚壳贻贝幼虫变态发育过程。在整个药理学实验过程中无死亡幼虫出现,因而氯甲酰胆碱和乙酰胆碱可作为有效诱导物来促进厚壳贻贝幼虫的变态发育,尝试应用于该种的水产养殖过程;同时本研究为厚壳贻贝变态发育调控机制的研究提供有效理论依据。     

Social and financial aspects of the artisanal fisheries of Middle São Francisco River, Minas Gerais, Brazil

The presence or absence of motorized boats, partnerships and multispecies catches characterize the fisheries of São Francisco River, Minas Gerais, Brazil. Fishing activity based on 109 interviews, carried out in the wet (high water: February and March) and dry (low water: July and August) seasons, with professional fishermen are described. Aiming to identify the fishery income components, a covariance model was proposed, with the income as the response variable, related to the factors: fishing ground; use of motorized or paddle boat; seasonality; presence of fishing assistant; and the following covariates: capture in weight in the week prior to the interview; fisherman experience in yrs; and distance (km) travelled for fishing. The results indicated that the main contributions to income were the absence of an engine (because of high price of the fuel), the absence of a partner (because of low capture) and the amount of fish caught by the fishermen.     

Functional partition of cells in the gill epithelium of the Japanese eel, Anguilla japonica, and the role of hormones

Viable chloride and pavement cells were isolated from the gill epithelium of Japanese eel, Anguilla japonica, by a 3-step percoll gradient centrifugation at low speed. Viability of the isolated cells were tested by the trypan blue exclusion test, rhodamine-123, or pre-labelling the cells with fluo-3 Ca²⁺ dye and examined by laser confocal microscopy. Isolated chloride cells responded to ionomycin with a rapid increase in Ca²⁺ fluorescence, which was abolished by chelating external Ca²⁺ with EGTA. Peptide hormones, including arginine vasotocin, isotocin, insulin-like growth factor I and II, and urotensin I increased Ca²⁺ entry, urotensin II had no effect, and eel corpuscles of Stannius extract reduced residual Ca²⁺ fluorescence. Isolated chloride cells and pavement cells from eels were analyzed for their enzymatic activities involved in intermediary and nitrogen metabolism. Chloride cells had high levels of glutaminase I, glutamate dehydrogenase, glutamate oxalacetate transaminase, HCO₃-ATPase and carbamoyl phosphate synthetase II. Pavement cells had highly active glucose-6-phosphate dehydrogenase and AMP deaminase. Both had high levels of lactate dehydrogenase compared with other tissues.     

Soy leaf lowers the ratio of non-HDL to HDL cholesterol in hamsters

The present study was to examine effect of soy leaf powder (SLP) and soy leaf ethanol extract (SLEE) on serum lipoproteins in hamsters. The control group was fed a semisynthetic diet containing 0.1% cholesterol, while the tested groups were maintained on the same diet but supplemented with 3% SLP or the equivalent amount of SLEE derived from 3% SLP for 4 weeks. SLP supplementation led to a trend of lowering serum total cholesterol (TC) and nonhigh density lipoprotein cholesterol (non-HDL-C), with HDL-C being unaffected, whereas incorporation of SLEE into the diet led to an elevated level of HDL-C and a lower level of non-HDL-C with TC being unchanged. Both SLP and SLEE supplementation caused favorably a decrease in the ratio of non-HDL-C to HDL-C. The present results demonstrate that not only soybean seeds but also soy leaves are cardioprotective, by favorably modulating serum lipid profile.     

羊草叶片SPAD值与叶绿素含量的相关分析

本研究采用SPAD叶绿素仪和酒精－丙酮浸提法测定河北沽源和内蒙古图牧集天然草原羊草的叶绿素SPAD值、叶绿素ａ、叶绿素ｂ和总叶绿素含量,探讨野外生态学实验采用叶绿素仪简便快速测定叶绿素的精确度。结果表明,在同一草原不同羊草个体之间羊草叶绿素含量和叶绿素SPAD值在一定范围波动,变异系数为20.457-36.921 %。河北沽源和内蒙古图牧集天然草原羊草叶绿素a、叶绿素b和总叶绿素含量随叶绿素SPAD值的增加而增加,呈线性函数、指数和幂函数规律变化,且均达到极显著相关水平,其中线性函数相关程度最大,可以更准确的预测羊草叶绿素含量。因此,可以利用SPAD-502叶绿素仪在野外条件下原位准确、快速地测定羊草叶绿素,为牧草生产实践提供理论依据     

人工草地建设对甘南草原土壤理化特性和微生物数量特征的影响

研究甘南草原高寒草甸退化草地人工种草后土壤理化性质和微生物数量特征,为退化草地的修复与利用提供参考。于2017年5,7,10月分别采集播种燕麦、黑麦及其未播种的草地土壤,测定其理化特性及微生物数量特征。结果表明:人工种植的黑麦草地土壤水分均大于燕麦人工草地,5,7月人工草地土壤含水量均显著大于对照草地,但10月差异不显著(P>0.05);pH在各月份不同播种方式下差异均不显著(P>0.05);土壤全氮、全磷在不同月份间差异亦不显著(P>0.05),但黑麦人工草地5月10—20cm层的有机碳、10月40—50cm层的全氮含量均显著大于燕麦人工草地及对照样地(P<0.05),7月20—30cm层燕麦人工草地的有机碳含量显著大于黑麦人工草地及对照草地;5月0—30cm层燕麦人工草地和黑麦人工草地的细菌数量显著高于对照草地的细菌数量(P<0.05),7月0—10cm层人工草地细菌数量显著高于对照草地(P<0.05),10月黑麦人工草地0—30cm层细菌数量均显著高于对照草地(P<0.05);5,10月真菌数量在0—10cm层人工草地显著高于对照草地(P<0.05),7月10—30cm层人工草地的真菌数量、0—10cm层的放线菌数量均显著高于对照草地(P<0.05);冗余分析发现,土壤细菌和真菌的变化具有联动性,且与土壤有机质、全氮、全磷等养分呈正相关。综上,人工种草后土壤养分的变化导致了土壤微生物数量的差异,这需要在草地管理中予以重视。     

玉米ZmNLP5与ZmSTP1、ZmAAP2基因启动子区域相互作用的鉴定

氮(N)是控制玉米产量的主要限制性因素,玉米对氮素的利用效率可以通过增加碳(C)的有效性得以改善。玉米转运蛋白ZmSTP1和ZmAAP2在植物C/N产物的运输和卸载过程中起着重要作用,且两个基因的启动子区域均含有一个硝酸盐响应顺式元件(nitrate responsive cis element, NRE)。NIN-like protein(NLP)是一类保守的植物特异性转录因子,已在多种植物被证实在调控N响应中发挥关键作用,其中玉米ZmNLP5是介导氮信号转导和代谢分子网络的中枢基因之一。为了明确ZmNLP5是否能与ZmSTP1和ZmAAP2基因启动子区域的NRE结合,以玉米B73为实验材料,首次利用酵母单杂交技术检测ZmNLP5与ZmSTP1、ZmAAP2基因启动子区域的相互作用。结果表明,将pGADT7-ZmNLP5-1/2分别转化Y1H (pAbAi-ZmSTP1)和Y1H(pAbAi-ZmAAP2)菌株后,在SD/-Leu培养基上均有菌落生长,在含AbA抗生素浓度为200 ng·mL^-1的SD/-Leu培养基中只有Y1H(pAbAi-ZmAAP2/pGA...     

A field guide for aging passerine nestlings using growth data and predictive modeling

Background: Accurate nestling age is valuable for studies on nesting strategies, productivity, and impacts on repro-ductive success. Most aging guides consist o...     

基于SSR标记的紫薇分子鉴定及遗传分析

以紫薇品种Lagerstroemia ‘Dynamite''（G2）、鄂薇1号（E1）、鄂薇4号（E4）以及W9互为亲本的杂交子代共40个优良单株为试材,利用14对在种内亲本间具有多态性的SSR引物对子代进行真杂种的鉴定,并利用GeneMarker、Popgene、Cervus和NTSYS 等软件对紫薇亲本和子代进行遗传多样性、聚类分析、AMOVA分析和主成分分析。结果表明：（1）有38个单株被鉴定为真杂种,杂种率为95%。（2）14对引物的多态信息指数（PIC）平均值为0.540 2,属于高度多态水平,群体平均等位基因数（Na）为4.5个,平均期望杂合度（He）以及Nei′ s基因遗传多样性指数（H）分别为2.602 2和0.594 7,平均Shannon′s信息指数为1.107 9。（3）来源于湖北野生紫薇品种E1单独聚在一个分支;而来源于美国紫薇品种的E4、W9和G2聚在一个大的分支上,另外一个个体23有别于3个亲本G2、E4和W9,单独一个分支;群体M2的5个个体,与24（M4）和32（M5）聚在一起,总体形成了3个大的组群。其中大部分个体都与其亲本聚在同一分支,但也有部分个体单独聚成一分支,这也说明部分杂交子代发生了遗传变异,体现出较丰富的遗传多样性。（4）AMOVA分析和主成分分析都表明了不同样本个体内产生了丰富的遗传变异。综上所述,筛选出的SSR标记可以有效地鉴定紫薇种内杂种以及反映紫薇种内的遗传多样性,因此该研究为紫薇品种的分子鉴定提供科学依据,同时也为后期种质资源收集、构建核心种质以及创制种内新品种奠定了理论基础。     

猕猴桃品种酚类物质及可溶性蛋白含量与抗溃疡病的关系

以安徽省猕猴桃主栽品种金魁、早鲜、魁蜜、华美2号、秦美、金丰为研究对象,于展叶孕蕾期分别取发病的枝条、叶片,以未发病健株的相应组织为对照,分析枝条、叶片中酚类物质和可溶性蛋白的含量变化。结果表明：抗病品种健株枝条、叶片中可溶性蛋白含量显著高于易感病品种,说明枝条中可溶性蛋白含量与品种抗性成正相关。自然发病后,感病品种枝条中可溶性蛋白含量增加,抗病品种可溶性蛋白含量降低。抗病品种健枝条、叶片中酚类物质含量高于易感病品种的健枝、叶,发病后抗感品种酚类物质含量都增加。