Effects of Overexpression of the Endogenous Farnesyl Diphosphate Synthase on the Artemisinin Content in Artemisia annua L.

Artemisinin is a novel effective antimalarial drug extracted from the medicinal plant Artemisia annua L. Owing to the tight market and low yield of artemisinin, there is great interest in enhancing the production of artemisinin. In the present study, farnesyi diphosphate synthase （FPS） was overexpressed in high-yield A. annua to Increase the artemisinin content. The FPS activity in transgenic A. ennue was twoto threefold greater than that In non-transgenic A. annua. The highest artemisinin content in transgenic A. annua was approximately 0.9% （dry weight）, which was 34.4% higher than that in non-transgenic A. annua. The results demonstrate the regulatory role of FPS in artemisinin biosynthesis.     

Nitric oxide potentiates oligosaccharide-induced artemisinin production in Artemisia annua hairy roots

The purpose of the present study was to characterize the generation of nitric oxide （NO） in Artemisia annua roots induced by an oligosaccharide elicitor （OE） from Fusarium oxysporum mycelium and the potentiation role of NO in the elicitation of artemisinin accumulation. The OE （0.3 mg total sugar/mL） induced a rapid production of NO in cultures, which exhibited a biphasic time course, reaching the first plateau within 1.5 h and the second within 8 h of OE treatment. Artemisinin content in 20-day-old hairy roots was increased from 0.7mg/g dry wt to 1.3 mg/g dry wt by using the OE treatment for 4d. In the absence of OE, the NO donor sodium nitroprusside （SNP） at 10, 50 ~1 and 100 ~1 enhanced the growth of hairy roots, but had no effect on artemisinin synthesis, The combination of SNP with OE increased artemisinin content from 1.2 mg/g drywt to 2.2 mg/g dry wt, whereas the maximum production of artemisinin in cultures was 28.5 mg/L, a twofold increase over the OE treatment alone. The effects of SNP on the OE-induced artemisinin were suppressed strongly by the NO scavenger 2-（4- carboxyphenyl）-4,4,5,5-tetramethylimidazoline-l-oxyl-3-oxide （cPTIO）. The results suggest that NO can strongly potentiate elicitor-induced artemisinin synthesis in A. annua hairy roots.     

Computational identification of sweet wormwood (Artemisia annua) microRNA and their mRNA targets

Despite its efficacy against malaria, the relatively low yield (0.01%-0.8%) of artemisinin in Artemisia annua is a serious limitation to the commercialization of the drug. A better understanding of the biosynthetic pathway of artemisinin and its regulation by both exogenous and endogenous factors is essential to improve artemisinin yield. Increasing evidence has shown that microRNAs (miRNAs) play multiple roles in various biological processes. In this study, we used previously known miRNAs from Arabidopsis and rice against expressed sequence tag (EST) database of A. annua to search for potential miRNAs and their targets in A. annua. A total of six potential miRNAs were predicted, which belong to the miR414 and miR1310 families. Furthermore, eight potential target genes were identified in this species. Among them, seven genes encode proteins that play important roles in ar- temisinin biosynthesis, including HMG-CoA reductase (HMGR), amorpha-4,11-diene synthase (ADS), farnesyl pyrophosphate synthase (FPS) and cytochrome P450. In addition, a gene coding for putative AINTEGUMENTA, which is involved in signal transduction and development, was also predicted as one of the targets. This is the first in silico study to indicate that miRNAs target genes encoding enzymes involved in artemisinin biosynthesis, which may help to understand the miRNA-mediated regulation of artemisinin biosynthesis in A. annua.     

Improve survival prediction using principal components of gene expression data

The purpose of many microarray studies is to find the association between gene expression and sample characteristics such as treatment type or sample phenotype. There has been a surge of efforts developing different methods for delineating the association. Aside from the high dimensionality of microarray data, one well recognized challenge is the fact that genes could be complicatedly inter-related, thus making many statistical methods inappropriate to use directly on the expression data. Multivariate methods such as principal component analysis （PCA） and clustering are often used as a part of the effort to capture the gene correlation, and the derived components or clusters are used to describe the association between gene expression and sample phenotype. We propose a method for patient population dichotomization using maximally selected test statistics in combination with the PCA method, which shows favorable results. The proposed method is compared with a currently well-recognized method.     

A method for the isolation and determination of ferric ethylenediamine di(o-hydroxyphenylacetic acid) in soil studies

Summary Contraversal results about the behaviour of Fe-EDDHA in soils is thought to be due to the indirect methods used for determining the iron chelate compound in soils. The purpose of this investigation is to develop a method for isolation of Fe-EDDHA from soil extracts inorder to be determined separatly. A 4% solution of tetra-n-heptylammonium iodide in ethyl alcohol was found effective in forming a water-insoluble but n-amyl alcohol-soluble compound of Fe-EDDHA. It was found that the absorption spectra of the iron chelate extracted with n-amyl alcohol has an absorption maximum of 480 mμ corresponding to that of iron chelate of the aqueous solution. The extracted iron chelate adhers to Beer's low in the range of 0 to 120 ppm of Fe-EDDHA. The method of Fe-EDDHA extraction was found to be selective for the isolation of the iron chelate from other soluble compounds. The procedure was also found to be highly efficient in quantitative isolation of Fe-EDDHA, with percent recovery ranging from 97–100. The incubation study of Fe-EDDHA in different soils indicated that the loss of Fe-EDDHA is associated with the organic matter content in the soil. The colorimetric determination of the total metal chelates did not indicate any replacement of other metals for the chelated iron in the soil.     

Effect of Development Stage on the Artemisinin Content and the Sequence Characterized Amplified Region （SCAR） Marker of High-Artemisinin Yielding Strains of Artemisia annua L.

The effects of development states on the artemisinin content of clone S1 of Artemisia anuua L. grown in a greenhouse were investigated in the present study. The artemisinin content increased gradually during the phase of vegetative growth and reached its highest level at 8-9 mg/g dry weight （DW） when the S1 was 6 months old on a long day （LD） photoperiod. Treatment with 9-18 d of short day （SD） photoperiod resulted in the artemisinin content reaching and being maintained at a higher level （2.059-2.289 mg/g DW）, twofold that of control plants and plants of S1 presented at the pro-flower budding and flower-budding stages. The artemisinin content varied in different parts of the plant. The artemisinin content of leaves was higher than that of florets and branches. The artemisinin content in middle leaves was higher than that of bottom leaves, and then top leaves. Different densities of capitate glands （the storage organ of artemisinin） located on the surface of leaves, florets, and branches explained the variations in artemisinin content in these parts of the plant. The correlation coefficient between artemisinin content and density of capitate glands on the surface of different organs was 0.987. The genetic marker for artemisinin content was screened using random amplified polymorphic DNA （RAPD） and sequence characterized amplified region （SCAR） techniques. The random primer OPAl5 （5＇-TTCCGAACCC-3＇） could amplify a specific band of approximately 1 000 bp that was present in all high-artemisinin yielding strains, but absent in all low-yielding strains in three independent replications. This specific band was cloned and its sequence was analyzed. This RAPD marker was converted into a SCAR marker to obtain a more stable marker.     

我国婴幼儿中存在不同基因型杯状病毒的感染

Human caliciviruses were detected from stool specimens collected from infants with diarrhea from Beijing and Anhui Province by using RT PCR PCR products with molecular weight around 330 were obtained by using the primer pair of 289/290,which is proved to be able to amplify both Norwalk like and Sapporo like human caliciviruses The PCR products amplified from specimens collected in Beijing(CR480) and Anhui(A141) were cloned into the T A cloning vector pUCm T and sequenced The cDNA fragment amplified from CR480 is 319bp in length,which is consistent with the molecular weight of the cDNA fragment amplified from Norwalk like viruses with the primer pair 289/290,whereas the cDNA fragment amplified from A141 is 331 bp in length,which is the size of the cDNA fragment from Sapporo like viruses The sequence analysis revealed that the cDNA from CR480(the stool specimen collected in Beijing) shared higher nucleotide and amino acid identities with selected Norwalk like viruses (from 60% to 97% and 62% to 99%,respectively)than with selected Sapporo like viruses(less than 58%),having the highest identity with Takl 1999 jp and ARG320,which belong to genotype Ⅱ of Norwalk like viruses The sequence of the cDNA from A141 (collected form Anhui Province) shared higher nucleotide and amino acid identities with selected Sapporo like viruses(from 68% to 92% and 75% to 96%,respectively) than with selected Norwalk like viruses(less than 52%) It suggests that both Norwalk like and Sapporo like human caliciviruses are circulating in China and cause diarrhea in infants and young childeren     

Altered Redox Status in Erythrocytes From Hypertensive Subjects： Effect of （-）Epicatechin

Hypertension is a major problem worldwide. There is much evidence to suggest that reactive oxygen species (ROS) radical may play a role in the development of organ damage associated with cardiovascular disease and hypertension. ( － )Epicatechin, a member of tea catechins belonging to flavonoid group, is known to be a potent anti-oxidant. The study has been undertaken to evaluate the effect of ( － )epicatechin on markers of oxidative stress: reduced glutathione (GSH) and membrane sulfhydryl ( — SH) groups in erythrocytes from hypertensive patients. The effect of ( － )epicatechin was also compared with a known anti-oxidant L-ascorbic acid. The erythrocyte intracellular GSH content and membrane — SH group content were significantly (P<0.01) decreased in hypertensive subjects. In vitro incubation with ( － )epicatechin caused an increase in GSH and — SH content, the effect was more pronounced in hypertensive erythrocytes. Similar results were obtained with L-ascorbic acid. The observed decrease in the level of GSH and — SH groups in hypertension is an indicator of oxidative stress condition. Observation of an increase in red cell GSH content and the protection of membrane — SH group oxidation by ( － )epicatechin in hypertensive subjects is a convincing reason to suggest that high dietary intake of foods rich in catechins may help to reduce oxidative stress and concomitant free radical damage in hypertensive patients.     

Back to the future of oridonin： again, compound from medicinal herb shows potent antileukemia efficacies in vitro and in vivo

Traditional Chinese Medicine （TCM） has been widely and successfully used in treating illnesses ranging from inflammation to cancer, and compounds from medicinal herbs and minerals are playing more and more important roles in taming various kinds of diseases [1 ], exemplified by artemisinin and arsenic trioxide （ATO）. Artemisinin （or Qinghaosu in Chinese） is isolated from a plant called sweet wormwood （Artemisia annua; or Qinghao in Chi- nese） which has been used as an antipyretic remedy for more than 1500 years in China. Artemisinin has impressive parasiticidal properties in vitro and in vivo, and is now one of the most important class of antimalarial agents [2, 3]. ATO is a common, naturally occurring substance which had been used in China for a long time as a therapeutic agent for some severe diseases with the ancient philosophy of ＇treating an evil with a toxic＇ [4]. In 1990s, ATO was shown to be able to cause partial differentiation at low dose and apoptosis at high concentration of acute promyelocytic leukemia （APL） cells [5], and induce complete remission in 90% of patients with relapsed or refractory APL [6-8]. These paradigms suggest that TCM is the treasure house not only for the Chinese people, but also for the whole human beings. It is our responsibility to develop evidence-based therapeutic approaches from TCM for diseases with poor prognosis.     

六种藓类植物茎的比较解剖学研究

通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.     

Cause of Senescence of Nine Sorts of Flowers

The levels of endogenous phytohormones and respiratory rate in nine sorts of flowers such as Cymbidium faberi Rolfe, Nopalxochia ackermannii Kunth and others were investigated both at full bloom and senescence and meanwhile the effect of exogenous phytohormones on prolonging the blossoms and promoting ethylene production were tested. There is a high content of endogenous ethylene in all the long-lived flowere, about 3–16 folds higer than the short-lived ones. There is a high level of ABA at full blooming flowers of short-lived flowers, in which there is no or only some cytokinins in it, but the ratio of CTK (6BA+zeatin)/ABA is smaller(l.7). The endogenous ABA reached a much higher level at senescence in all nine sorts of flowers, so it is reasonable to consider that it is ABA which plays an important role of regulation in controlling flower's senescence. There is a much higher level of GA3 and zeatin in the long-lived flowers which is not demonstrated in the shortlived ones. The respiratory rate is one of the factors controtling the longevity of flowers, but it does not play a decided role. Application of 6BA and zeatin prolongs distinctly orchid’s longevity, however exogenous IAA through the promotive action on ethylene production, evidently extends the longevity of the flowers of the Nopalxochia ackermannii Kunth.     

真菌类遗传学分析的知识结构教学

本文以认知结构理论为指导,讨论了真菌类遗传分析与高等动植物遗传分析的内在联系,认为利用这种内在联系进行教学可收到好的效果并说明了作者的具体教学过程。 Abstract:In the paper, the relationship between genetic analysis of Fungi and genetic analysis of high animal and plant was discussed.A good results were obtained when we adopted this method in the teaching.     

医疗机构合理用药评价模型的构建研究

目的 针对医疗机构的合理用药水平进行评价研究。方法 根据医疗机构合理用药的具体要求,构建医疗机构合理用药评价指标体系,采用基于模糊群决策的方法和多指标评价分析法构建医疗机构合理用药评价模型。结果 构建了基于模糊群决策的医疗机构合理用药评价模型,并通过实例分析证明了评价模型的可行性。结论 建立的基于模糊群决策的医疗机构合理用药评价模型能够对医疗机构的合理用药水平进行科学评价,为提高医疗机构合理用药水平奠定基础。     

棉铃虫钙粘蛋白N端多肽多克隆抗体制备及对Bt抗性的初步检测

用重组表达的棉铃虫Helicoverpa armigera(Hübner)中肠钙粘蛋白N端多肽片段制备兔多克隆抗体,并利用其对Bt抗性进行鉴定。通过RT-PCR方法对棉铃虫中肠钙粘蛋白N端多肽的基因片段Cad285进行PCR扩增,将其克隆到pET-30a原核表达载体中,在大肠杆菌BL21(DE3)中经IPTG诱导表达,得到35ku的重组融和蛋白,融合表达的包涵体经过变性、Ni-NTA柱亲和纯化、复性等方法处理包涵体,获得可溶性纯化蛋白,用纯化后蛋白免疫新西兰兔制备多克隆抗体,ELISA检测其效价高于1∶16000;利用最终获得的多克隆抗体对室内纯合Bt抗/感品系的棉铃虫中肠钙粘蛋白进行Western blot分析,结果显示敏感和抗性品系之间有明显差异,表明其能够应用对Bt抗性进行初步检测。     

龙胆科药用植物化学成分的研究现状

龙胆科植物在我国的分布范围很广,且多数为药用植物,其多数种属的药用植物,至今其化学成分尚未被系统研究。综述了目前龙胆科药用植物的化学成分的研究现状及一般提取方法,对近年来发现的环烯醚萜及裂环烯醚萜类化合物进行了总结,为本科药用植物的更深入研究提供了参考。     

青蒿素生物合成机理研究现状

本文总结了目前有关青蒿素生物合成机理方面的研究,主要包括青蒿素生物合成中生理因子的影响,青蒿素生物合成中间体及前体,青蒿素生物合成细胞定位等。指出了存在的一些问题及今后的研究发展前景。