Ecotoxicity of soils contaminated with industrial and domestic wastewater in western shenyang,China

Soil samples were collected from 7 sites in the up-, mid-and down-reach along and nearby the wastewater irrigation channel, western Shenyang of China. The concentrations of selected pollutants (mineral oil, PAHs - polycycle aromatic hydrocarbons and Cd) were determined by UV spectrometer, HPLC and AAS (atomic adsorption spectrometer) spectrometer, respectively. Toxicity effects of soils were evaluated by seedling emergence test with root length of wheat as the end-point and by earthworms test with the mortality rate and inhibition rates of body weight as endpoints. Results showed accumulation of pollutants for most soils with concentration of 200.2 mg.kg⁻¹∼1600 mg.kg⁻¹ for mineral oil, 0.33 mg.kg⁻¹∼1.81 mg.kg⁻¹ for Cd and 900.16 mg.kg⁻¹ ∼ 2737.91 mg.kg⁻¹ for PAHs. The inhibition rates of root elongation were from −20% up to 40 %, and mortality rates of earthworms ranged from 0%∼40% from the exposure period of two weeks to eight weeks by sampling interval of two weeks, the inhibition rates of earthworm growth were from −19.36% to 34.53%, showing effects of stimulation at 2 weeks to an increasing effects of inhibition at 4, 6 and 8 weeks, respectively. Mortality rates correlated with the loss of body weight of earthworms.

This study indicated the potential risk of pollutants of environmental low content in soil by the determination of selected chemicals combined with toxicity indexes.

     

Studies on anabolic steroids--12. Epimerization and degradation of anabolic 17 beta-sulfate-17 alpha-methyl steroids in human: qualitative and quantitative GC/MS analysis.

The epimerization and dehydration reactions of the 17 beta-hydroxy group of anabolic 17 beta-hydroxy-17 alpha-methyl steroids have been investigated using the pyridinium salts of 17 beta-sulfate derivatives of methandienone 1, methyltestosterone 4, oxandrolone 7, mestanolone 10 and stanozolol 11 as model compounds. Rearrangement of the sulfate conjugates in buffered urine (pH 5.2) afforded the corresponding 17-epimers and 18-nor-17,17-dimethyl-13(14)-enes in a ratio of 0.8:1. These data indicated that both epimerization and dehydration of the 17 beta-sulfate derivatives were not dependent upon the respective chemical features of the steroids studied, but were instead inherent to the chemistry of the tertiary 17 beta-hydroxy group of these steroids. Interestingly, in vivo studies carried out with human male volunteers showed that only methandienone 1, methyltestosterone 4 and oxandrolone 7 yielded the corresponding 17-epimers 2, 5 and 8 and the 18-nor-17,17-dimethyl-13(14)-enes 3, 6 and 9 in ratios of 0.5:1, 2:1 and 2.7:1, respectively. No trace of the corresponding 17-epimers and 18-nor-17,17-dimethyl-13(14)-enes derivatives of mestanolone 10 and stanozolol 11 was detected in urine samples collected after administration of these steroids. These data suggested that the in vivo formation of the 17-epimers and 18-nor-17,17-dimethyl-13(14)-enes derivatives of 17 beta-hydroxy-17 alpha-methyl steroids is also dependent upon phase I and phase II metabolic reactions other than sulfation of the tertiary 17 beta-hydroxyl group, which are probably modulated by the respective chemical features of the steroidal substrates. The data reported in this study demonstrate that the 17-epimers and 18-nor-17,17-dimethyl-13(14)-enes are not artifacts resulting from the acidic or microbial degradation of the parent steroids in the gut as previously suggested by other authors, but arise from the rearrangement of their 17 beta-sulfate derivatives. Unchanged oxandrolone 7 was solely detected in the unconjugated steroid fraction whereas unchanged steroids 1, 4 and 11 were recovered from the glucuronide fraction. These data are indirect evidences suggesting that the glucuronide conjugates of compounds 1 and 4 are probably enol glucuronides and that of compound 11 is excreted in urine as a N-glucuronide involving its pyrazole moiety. The urinary excretion profiles of the epimeric and 18-nor-17,17-dimethyl-13(14)-ene steroids are presented and discussed on the basis of their structural features.     

纪念蒋英教授

蒋英教授是著名的植物分类学家。他从事中国夹竹桃科、萝藦科、番荔枝科植物的专门研究和教育事业有五十四年历史,为祖国科学事业奋斗一生,作出了重大贡献。本文详细地介绍了他的生平、艰苦创业的经过、严谨治学精神、培养人才的经验,并总结了他一生的科研成就和八十多篇著作名录,供后人参考。     

烟草愈伤组织分化和芽原基形成期间呼吸代谢途径的改变

接种在继代培养基上的柳叶烟草愈伤组织,未观察到组织分化和芽原基形成。在分化培养基上生长的愈伤组织,接种后第6天可见拟分生组织和管胞分化,9—12天有芽原基形成,15—18天可观察到苗端结构。根据碘乙酸、Na_3PO_4和丙二酸抑制试验,以及3-磷酸甘油醛脱氢酶与琥珀酸脱氢酶活性测定结果,初步表明烟草愈伤组织呼吸中存在有EMP、HMP和TCAC代谢途径.在发生输导组织和芽原基分化的愈伤组织中(接种后第6—12天),HMP途径的运行程度较高;而芽原基的继续生长(培养12天以后),则与EMP途径的增加有关;分化培养基上生长的愈伤组织,始终较继代培养愈伤组织具有较高的FCAC活性水平。     

循环血中GM-CFC的性能研究

利用造血细胞体外琼脂培养技术,比较了狗的不同来源的GM—CFC增殖、分化性能和辐射敏感性。结果表明,在正常生理条件下循环血中GM—CFC集落产率约为骨髓的1/60;细胞集落开始形成时间较骨髓晚1天,细胞集落随培养时间(前3—5天)增加而增加,其增加速率约为骨髓的20%;辐射敏感性D_0值为0.34Gy,明显低于骨髓中GM—CFC的D_0值(0.82Gy)。造血干细胞动员剂动员后血中GM—CFC数量明显增加,细胞集落增加速率约为骨髓的59%,D_0值为0.72Gy。从而为循环血干细胞移植疗效提供了实验依据。     

几个生态因子对黄盖鲽的影响

黄盖鲽(Psuedopleuronectes yokohameGünther)是鲽科中的冷温性鱼类,广泛分布在日本、朝鲜及我国的东海、黄海和渤海。地方种群多,洄游范尉小,适应能力强,既是底栖生物食性,又可耐较低的温度,虽非名贵鱼种,却具有一定的经济价值,在开展近海增殖时,不存在越冬和效益外流问题。因此,早在60年代,日本山口县和大分县的学者们,便开始着手该品种的人工孵化和增殖放流试验。80年代初已达年放流2—3cm的稚鱼苗7.0×10~6尾的水平。为了在渤海开展增殖工作,建立综     

稻草—凤尾菇—蚯蚓—肉鸡食物链的氮流与能流研究

稻草养菇、菇渣喂蚓、以蚂喂鸡是通过营养关系将三个生产过程有机地连接起来,形成农业生态系统特有的食物链。关于这三个环节各自的经济效益及栽培技术方面的研究工作已经做了很多,而作为一条食物链的整体状况,主要是能流和物流状况。尚未见到更深入具体的报道。作者试图通过实验定量分析和评价该食物链中每一链节上以及整体上的氮流和能流状况,进而对其生产应用价值做一初步探讨。     

Sequence analysis of a cDNA containing the gag and prot regions of the soybean retrovirus-like element, SIRE-1

SIRE-1 is a family of several hundred dispersed copies of a very large DNA element from Glycine max that has features characteristic of retroviruses and retrotransposons. A 2.4 kb SIRE-1-specific fragment was recovered from a soybean cDNA library and sequenced. The sequence contains two ORFs. Theoretical translation of ORF1 produces a gag-prot-like polyprotein containing highly conserved motifs found in retroelement nucleocapsids (CX₂CX₄HX₄C) and aspartic proteases (LDSG). The second ORF is foreshortened. The cDNA also contains nearly 200 bp of a putative 5 LTR just upstream of a tRNA primer-binding site.     

丙型肝炎病毒基因组部份NS5区蛋白基因在大肠杆菌中的表达

在大肠杆菌中表达了丙型肝炎病毒基因组ＮＳ５区Ａ段和部份Ｂ段蛋白。ＮＳ５Ａ蛋白溶于水,可经过ＧＳＴ亲和层析柱纯化;ＮＳ５Ｂ蛋白不溶于水,经ＰＢＳ－Ｔｒｉｔｏｎ Ｘ－１００洗涤,尿素溶解后,通过离子交换柱纯化。经ＳＤＳ－ＰＡＧＥ和Ｗｅｓｔｅｍｂｌｏｔ分析,ＮＳ５Ａ蛋白除在５７ｋＤ左右有条带外,还有不同程度的降解产物;ＮＳ５Ｂ蛋白主要在５８ｋＤ左右有条带出现。为查明表达蛋白抗体在病人血清中的分布,取９