通过分析生物科学专业开设"环境科学导论"的教学实践,对其课程设置目的、教学内容调整、教学方法改进和考核体系设置进行了介绍和讨论,尤其对充分利用网络视频资源、丰富教学内容和手段,采用翻转课堂教学模式、引导学生直接参与教学活动,以及鼓励学生进行社会调查、参观和交流的教学方式进行了探索.指出生物科学类专业开设"环境科学导论"课程,有利于学生强化与生物科学专业紧密相关的环境科学基础理论知识,以及技术的学习,增强学生保护自然生态环境意识,巩固专业知识,拓宽就业面.

生物科学是一门综合性实验学科.其核心课程体系的构建和众多基础理论概念的提出,都是建立在大量的科学实验基础之上的.为培养学生分析问题和解决问题的能力,按实验课程性质分类,需开设基础性、综合性、研究创新性实验课程.近几年,许多高校又陆续开设了自主开放性实验课程.我校为生物科学类专业开设开放性实验已多年,本文就生物科学专业开放性实验开设的教学与管理实践作交流.

为明确钾营养供应对烟碱生物合成的影响规律,采用定量PCR和气相色谱-质谱联用法,研究不同供钾量条件下,烟草叶片烟碱含量和根系腐胺N-甲基转移酶(PMT)与喹啉酸磷酸核糖基转移酶(QPT)的表达情况.结果 表明,低钾供应会增加烟叶的烟碱含量、促进根系PMT基因的表达;高钾供应对烟叶的烟碱合成和根系的PMT基因表达具有明显的抑制效应.低钾处理后再恢复正常钾供应水平,可显著降低由低钾供应对烟碱合成和PMT基因表达的促进作用.不同的供钾水平同样影响QPT基因的表达水平,但与烟碱积累量的变化不存在明显的相关性.因此,烟草植株的烟碱含量受供钾水平的影响,钾可能通过控制根系腐胺N-甲基转移酶基因的表达来影响烟叶中烟碱的积累.

本文就环境生物学作为通识课开设而在课程教学内容调整、教学方法改进,以及考核方法设定等方面进行了尝试,并讨论了所存在的问题和需改进的方面.

Oxidation of LDL has been regarded as the key factor which leads to AS, the fluorescent characteristic of LDL developed a series of changes during LDL oxidation. The traditional and three-dimensional flourescence contour spectroscopy were used to evaluate the inhibition effects of clove against the changes of fluorescent characteristic of LDL in the process of oxidation in this paper. The results indicated as follows: the optimal measurement time point of LDL incubation for fluorescence was 48 h; fluorescence of Trp quenching, fluorescent chromophore redshift, Lys residues contained in apoB-100 being modified by reactive aldehydes generated during oxidation, the generation of fluorescent materials and lipofuscins and the variation of three-dimensional fluorescence were significantly inhibited, respectively, and the inhibition effects were positively related with concentrations of clove crude extracts. Moreover, in this experiment it was found that the different polarity components of clove (n-hexane fraction (clove essential oil), ethyl acetate fraction, n-butyl alcohol fraction and water fraction) possessed different activities on influencing the changes of fluorescent characteristic of LDL during LDL oxidation. Among these fractions, n-hexane fraction possessed the strongest activities against Trp fluorescence quenching, fluorescent chromophore redshift and the variation of three-dimensional fluorescence. However, the inhibition efficiencies of ethyl acetate fraction were the highest against the generation of fluorescent materials and lipofuscins, Lys residues being modified by reactive aldehydes. The results suggest that clove has the preferable inhibitory action on the variation of fluorescence characteristic during LDL oxidation, and the main components of inhibition focus on the essential oil and ethyl acetate fraction. This research provides a reference on further components analysis, research and development of functional foods of clove.

Soybean [ Glycine max(L. ) Merr. ] seedling hypocotyls were treated with exogenous polyamine and ami-noguanidine to explore the regulating mechanism of polyamine on polyamine oxidase in adventitious root regeneration. The number of adventitious roots, the changes of diamine oxidase gene expression and the enzyme activity were measured. Low concentrations of putrescine ( Put) , spermidine ( Spd) and spermine ( Spm) significantly promoted the growth of soybean hypocotyl adventitious roots, and the optimum concentrations were 1. 00 mmol/L、0. 25 mmol/L and 0. 05 mmol/L, respec-tively. On the contrary, polyamines at high concentrations showed inhibitory effects. The gene expression level of CuAO was up-regulated by polyamines and maintained a high level afterwards. Correspondingly, the CuAO activity was gradually in-creased by exogenous polyamines during the regeneration of adventitious roots. Put showed the best effect. In addition, the role of aminoguanidine ( AG, a specific inhibitor of CuAO) was detected. It could significantly inhibit the growth of soybean ad-ventitious root, which might be related to the inhibition of CuAO activity by AG. These results imply that the expression of CuAO gene can be induced by exogenous polyamines, the induction of CuAO gene expression and the improvement of the enzyme activi-ty might have contributed to the promotion of soybean hypocotyl adventitious root growth.

The characteristics of comprehensive experiments of Plant Biology were analyzed.The design, teaching management and the"three stage implementation methods"of comprehensive experiments of Plant Biology were introduced.And the main problems existing in the process of comprehensive experiment teaching were analyzed.

Cotyledon node callus of soybean seedlings was used to study the role of hydrogen peroxide from polyamine degradation in induced generation of clump buds in soybean cotyledon node callus. The results showed that three of the exogenous polyamines significantly enhanced clump buds formation of soybean cotyledon node callus,0. 5 mmol·L- 1Put was more effective than Spm,but less than Spd. Meanwhile cyclohexylamine( CHA),an inhibitor of Spd synthase,displayed a strong inhibitory effect on the formation of clump buds. Accordingly,activity of diamine oxidase and levels of hydrogen peroxide in the explants of cotyledon node were greatly increased. Interestingly,polyamine-increased differentiation of clump buds was strongly reduced after the application of diamine oxidase inhibitor-aminoguanidine( AG) and H2O2scavenger- dimethyl thiourea( DMTU),respectively. Probably,the effects of AG and DMTU on clump buds differentiation were associated with decreases in Cu AO activity and the level of H2O2 caused by AG treatments,and H2O2 scavenging by DMTU. These results suggest that hydrogen peroxide from polyamine degradation is potentially involved in inductive formation of clump buds in soybean cotyledon node callus.

Polyamines (PAs) induce nitric oxide (NO) generation in plant tissues; however, their mechanism is still unclear. In the present study, suspension cells of soybean cotyledon-node callus were employed. Using a NO-specific fluorescent dye, DAF-FM-DA (3-amino, 4-aminomethy1-2', 7'-difluorescein, diacetate), and laser confocal scanning microscopy, changes in NO generation induced by exogenous PAs were examined. The results of this study showed that NO fluorescence was significantly induced above endogenous levels when callus cells were treated with 0.05 mM PAs. However, putrescine (Put) was the most active PA. The observed NO release by PAs was rapid and without an apparent lag phase. The response was quenched when the suspension cells were treated with the NO-specific scavenger cPTIO (2-(4-carboxypheny1)4,4,5,5-tetramethylimidazoline-1-1-oxy-3-oxide). When 0.01 mM L-aminoguanidine (L-AG) was applied prior to the PA treatments, the NO fluorescence was diminished, and the inhibition of NO fluorescence was correlated with a decrease in diamine oxidase (DAO) activity. When callus cells were incubated with 0.1 mM catalase (CAT) and 1.0 mM N'N-dimethylthiourea (DMTU) prior to PA application, NO release was significantly reduced. In sum, our data provided evidence for PA-induced NO generation in suspension cells of soybean cotyledon node callus and demonstrated that peroxide, potentially derived from PA oxidative degradation, was involved in NO release induced by PAs. (C) 2014 Elsevier Masson SAS. All rights reserved.

The in vitro culture of Echinodorus subalatus was established by using the unelongated stem as explants. The method of surface sterilization of explants,the effects of different plant growth regulators on the multiplication and rooting were investigated. The results showed that 20% sterile explants could be obtained by twice surface treatment with 0.1% HgCl2 for 8 min and 6-8 min with an interval of 24 h. When cultured on a 1/2 MS multiplication medium supplemented with 6.0 mg·L-1 of 6-BA for 42 d,the test-tube seedling exhibited a multiplication coefficient of 9.3. For optimal rooting,induction on a 1/2 MS rooting medium supplemented with 0.2 mg·L-1 of NAA for 28 d could produce rooted plantlets with 100% rooting rate,and each plantlet generated about 18 roots on average. Rooted plantlets were acclimatized and transferred into outdoor aquatic environment with 100% survival rate.

Lettuce(Lactuca sativa L.) Guasihong was used as a material to study some subtances metabolism and hydrolase activities of lettuce seed soaked in nitric oxide(NO) inhibitor L-NAME and different concentrations of NO donor sodium nitroprusside(SNP) during seed germination.The results indicated that the germination rate of lettuce seeds soaked in 0.10 mmol/L SNP for 36 h was higher than those in 0 mmol/L,0.05 mmol/L,0.20 mmol/L SNP.The seed germination was improved with 0.10 mmol/L SNP for 12-36 h,but declined after 48 h.1.00 mmol/L L-NAME significantly inhibited the seed germination.The starch content of lettuce seed significantly decreased and soluble sugar significantly increased in 0.10 mmol/L SNP treatment.The starch degradation was inhibited and the soluble sugar content markedly declined in 1.00 mmol/L L-NAME treatment.The activities of α-amylase,nitrate reductase and lipase were increased with the extension of time,and β-amylase activity reached the peak after being soaked for 36 h and then declined.The activities of β-amylase,α-amylase,nitrate reductase and lipase dropped in 1.00 mmol/L L-NAME treatment.

Soybean[Glycine max(L.) Merr.] cv."Jilin pellets 7" seeds were used to study the role of polyamine oxidative degradation in the rooting of soybean cotyledon node.The results showed that exogenous polyamines(Put,Spd and Spm) significantly enhanced rooting of soybean cotyledon node,while cyclohexylamine(CHA,an inhibitor of Spd synthase) inhibited rooting of soybean cotyledon node.Aminoguanidine(AG,a specific inhibitor of polyamine oxidases) strongly blocked the differentiation of soybean cotyledon node.Meanwhile diamine oxidase(DAO) activities and H2O2 content decreased and endogenous polyamine contents simultaneously accumulated to some extent.N,N-dimethylthiourea(DMTU,a scavenger of H2O2) inhibited rooting of soybean cotyledon node,and could markedly reduce the PAs-promoted effect on rooting of soybean cotyledon node.These results suggest that the differentiation of soybean cotyledon node to form adventitious roots is associated with the oxidative degradation of polyamines,and that their products,especially H2O2,may be involved in this process.

Normal lettuce seeds(Lactuca sativa L.)were used to study effects of the H2O2 produced from polyamine degradation in the process of lettuce seed germination after treatments with cyclohexylamine(CHA,a specific inhibitor of Spd synthase),aminoguanidine(AG,an inhibitor of polyamine oxidases) and N,N'-dimethylthiourea(DMTU,a scavenger of H2O2).The results showed that three exogenous polyamines especially 0.5 mmol/L Spd could significantly promote the germination of lettuce seeds.Consistent with the result,CHA had an inhibitory effect on the germination of lettuce seeds.Spd induced germination of lettuce may be relevant to the H2O2 production from polyamine degradation.Because Spd could significantly promote the activity of polyamine oxidases and increased H2O2 content of imbibed seeds.DMTU could diminish the promotive effects of Spd on seed germination as it could low Spd induced increase of H2O2.AG also alleviated the Spd promotive effects on seed germination due to its inhibitory role in PAO activity.These results suggest that H2O2 produced from polyamine degradation may be involved in the process of lettuce seed germination.

[Objective]The aim of this study was to understand the role of polyamine oxidative degradation in the process of lettuce seed germination. [Method]After lettuce seed soaking treatments with aminoguanidine (AG,a specific inhibitor of polyamine oxidases),seed germination rate,activities of polyamine oxidase (PAO) and diamine oxidase (DAO),change of endogenous polyamine and H2O2 content were determined. [Result]Compared with the control,AG treatment strongly inhibited the seed germination,which also had an extremely significant difference in seed germination rate after incubation for 12 h. During the seed germination,activities of PAO and DAO significantly changed,while their activities firstly increased and then decreased,then DAO and PAO reached peaks at 24 h and 48 h respectively. AG treatment was strongly inhibitory for activities of DAO and PAO,whose activities even disappeared after incubation with AG for 24 h and 36 h. During the seed germination,endogenous Put reduced sharply in the first 24 h,then reduced slowly in 24-60 h,while Spd decreased slowly in the early stage of germination,and then sharply declined after 48 h. However,Spm content was low but slightly increased,and the total polyamine gradually decreased. AG treatment could significantly increase endogenous polyamines,especially Put and Spd contents. During the seed germination,H2O2 content gradually increased,and had a peak from 36 to 48 h,then kept a high level at last. AG treatment could significantly reduce H2O2 content. [Conclusion]During the seed germination,the changes of endogenous polyamine and H2O2 content correspond with the changes of PAO and DAO activities,which indicate that there is an active polyamine metabolism of oxidative degradation during the lettuce seed germination.

Using lettuce seeds(Lactuca sativa L.‘Guasihong’)as a material,the role of exogenous polyamines(PAs)and nitric oxide(NO)in the process of lateral root development in lettuce seedlings and their relationship were investigated.As a result,treatments with exogenous PAs at low concentrations were able to increase the levels of endogenous PAs and to promote the formation and development of lateral roots,and their optimal concentrations were 0.05 mmol · L-1.Consistently inhibitors of polyamines biosynthesis cyclohexylamine(CHA)and methyl-glyoxal-bis-guanyhyldrazone(MGBG)significantly reduced the development of lettuce lateral roots.Like PAs,exogenous NO donor sodium nitroprusside(SNP)also promoted the development of lettuce laterals.When treated with SNP and PAs,the application of NO scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide(cPTIO)could markedly prevented the SNP-or PAs-promoted effects on lateral roots.Fluorescent detection using the 1,2-diaminonanthraquinon(eDAQ),a NO-sensitive fluorescent probe,showed that lateral root primordia treated with PAs or SNP emitted strong NO fluorescence,which could be eliminated by cPTIO,concomitantly with its inhibitory effect on lateral root emergence promoted by PAs or SNP.All together,these results suggest that NO is probably involved in PAs signaling pathway during the process of PAs induced development of lateral roots in lettuce seedlings.

<正>世界卫生组织总干事陈冯富珍博士2007年11月2日在中国卫生部发表的"以国际视角看中国卫生"的专题演讲中指出:"卫生不再只是消耗资源,卫生同样也会产生经济成果。健康是繁荣的基础,卫生

This article clarified the ability of public health emergency response, introduced the situation of public health emergency response system at Zhangjiagang port, and discussed public health emergency response system combined with the work of frontier quarantine. Public health security at frontier is not only related to the development of foreign trade, but also related to national security and stability. So we need to establish a relatively stable and reliable response system for public health emergencies at frontier. ‘International Health Regulations (2005)’ is direction for the construction of public health emergencies response system.

Normal lettuce seeds(Lactuca sativa L.cv Guasihong) were used to understand the relationship between polyamines and nitric oxide(NO) in the process of seed germination after treatments with exogenous polyamines and NO donor SNP(sodium nitroprusside) together with NO specific scavenger cPTIO.The results showed that exogenous polyamines,especially Spd,had a certain role in promoting early germination and the optimal concentration was 0.5 mmol·L-1.Their effect was more significant before 48 h after seed imbibition.Consistent with the result,1.0 mmol·L-1 cyclohexylamine(CHA,spermidine synthase inhibitor) had a strong inhibitory effect on the germination of lettuce seeds.Like Spd,exogenous NO donor SNP also promoted seed early germination of lettuce,but in a concentration-dependent way,its function disappeared after 48 h.When treated with SNP and Spd,application of NO scavenger cPTIO could markedly reduce the SNP-or Spd-promoted effect on lettuce seed germination.Fluorescent detection using the DAQ,a NO-sensitive fluorescent probe,showed that there was strong NO fluorescence near seed embryo treated with Spd or SNP.The fluorescence could be eliminated by cPTIO concomitantly with its inhibitory effect on the early germination promoted by Spd or SNP.In this paper,we preliminarily approve that polyamines-,especially spermidine-induced early germination of lettuce seeds may be relevant to the NO induction.

就精胺的代谢和生物合成相关基因以及在植物耐逆境胁迫中的特异性作用研究进展作概述.