发光细菌法快速监测和评价工业废水综合毒性

以汞、镉、铅、砷和六价铬的混合后对发光细菌的综合毒性为参照标准,对工业废水进行快速监测和毒性分级的研究,实验得出上述混合毒物与发光细菌的发光强度的相关关系是y＝40.9131-23.7200lnx,r-0.995。根据工业废水的相对发光强度,建议将工业废水划分为微毒,低毒、中等毒,高毒和剧毒五个毒性级别,并可根据上述线性关系,推算出有毒物质的浓度范围和相当于国家标准的倍数。应用此法对22份工业废水进行了实际测定与评价;还对四个企业工业废水处理前后的毒性进行了测定与毒性比较,结果表明处理后较处理前的毒性的毒性明显降低。     

斑马鱼胚胎发育技术在毒性评价中的应用

对斑马鱼（Brachydanio rerio)胚胎发育技术在环境科学领域的应用作一综述,斑马鱼胚胎毒性技术是各国际标准组织认可的标准毒性测定方法之一,属于致畸效应检验,该项技术成本低、易操作、灵敏度高,特别是具有可记录多项毒性指标的特点,并可以此判断污染物的致毒机理,斑马鱼胚胎发育过程受重金属影响较大,其中Cu的毒性最强,Hg次之,Cr最弱,有机农药中三苯基锡类（TPTA）的毒性最强,林丹次之;有机试剂中含卤素取代基和苯胺类毒性最大,这与其它毒性测定方法的结果完全一致,并表现出较高的灵敏度,特别是选用非致死性的指标,可以初步认定这对测定复合污染物毒性并分析毒物的致畸效应方面有很好的发展前景。     

FAPα酶激活式靶向抗肿瘤前药: Z-GP-Dox对斑马鱼的毒性评价

目的:考察新设计合成的一种FAPα酶激活式靶向抗肿瘤新药甘脯酰阿霉素(Z-GP-Dox)对斑马鱼的毒性作用。方法:以阿霉素作为对照,用不同浓度的Z-GP-Dox处理4月龄的成年斑马鱼及其受精后24h(24hpf)的胚胎,观测其死亡率,并通过显微镜观察Z-GP-Dox对斑马鱼胚胎发育的影响,从形态学和电生理学方面评价其对斑马鱼心脏的毒性作用。结果:Dox对照组的斑马鱼死亡率具有明显的浓度依赖性,而经酰化修饰的前药Z-GP-Dox处理组的斑马鱼死亡率相对较低。Dox可导致斑马鱼胚胎发育严重畸形,心脏功能受损;而相同浓度的前药Z-GP-Dox处理组的胚胎发育基本正常,幼鱼的心脏形态和心率与空白对照组差异不显著。然而,当Z-GP-Dox被FAPα酶解后,其毒性则明显增强,与Dox对照组的毒性相当。结论:与Dox相比,经结构改造的前药Z-GP-Dox对斑马鱼的毒性显著降低,且具有FAPα酶激活式靶向释放特性。     

夹竹桃叶乙醇提取物对斑马鱼的毒性评价

研究表明,夹竹桃(Nerium indicum Mill.)及其提取物对多种害虫具有较强的毒杀作用,已在害虫生物防治中显示出较大作用。为了合理开发夹竹桃植物,需要进一步评价夹竹桃植物对水生生物的安全性和对动物的毒理学。文章利用索氏提取法提取夹竹桃叶乙醇粗提物,并进一步用氯仿萃取浓缩、硅胶柱层析方法提取分离乙醇精提物,经鉴定为强心甙组分。在此基础上,委托浙江省医学科学院评价了乙醇粗提物对实验动物的毒理学,并采用静态法评价了这二种提取物对斑马鱼(Brachydanio rerio)的急性毒性和慢性效应。结果表明:夹竹桃叶乙醇粗提物的提取率为45%,乙醇精提物(主要成分为强心甙组分)的提取率为0.25%。乙醇粗取物对大鼠经口和经皮毒性为低毒级,对家兔皮肤和眼无刺激,对豚鼠的致敏反应属弱致敏性。这说明夹竹桃叶乙醇粗提物对哺乳动物十分安全。在急性毒性试验中,发现斑马鱼的死亡率与提取物处理浓度和处理时间均呈明显的正相关。处理浓度越大,斑马鱼的死亡率越高;同一浓度处理时间越长,死亡率越高。用24 mg/L乙醇粗提物处理6、12、24和48h的死亡率分别为26.67%、60%、91.11%和95.56%;用0.5 mg/L乙醇精提物处理12、24、48、72和96h的死亡率分别为6.25%、33.33%、52.08%、54.17%和60.42%;用24 mg/L乙醇粗提物处理96h或32 mg/L处理48h,或者用1 mg/L乙醇精提物处理24h,斑马鱼全部死亡。在慢性毒性试验中,用3.33—10.0 mg/L乙醇粗提物处理斑马鱼28d,其死亡率为12%—20%。乙醇粗提物处理斑马鱼后,急性毒性LC50=12.52 mg/L(药后96h)>10 mg/L,慢性毒性LC50=199.51 mg/L(药后28d);乙醇精提物处理斑马鱼后,急性毒性LC50=0.46 mg/L(药后96h)<1 mg/L,根据《化学农药环境安全评价试验准则》(1990)中农药对鱼类的毒性分级标准,说明夹竹桃叶乙醇粗提物对斑马鱼的毒性属于低毒,比较安全;乙醇精提物对斑马鱼的毒性则为高毒,十分不安全。     

餐厨垃圾高温菌种对斑马鱼急性毒性与安全评价

目的:研究餐厨垃圾高温菌种对斑马鱼的毒性,为其安全使用提供依据。方法:以具有代表性的水生动物斑马鱼为试材,采用静态法测定餐厨垃圾高温菌种对斑马鱼急性毒性并对其进行安全评价。结果:鱼的半数致死浓度LC50值24、48和96h分别为3400mg/L、3000mg/L和2500mg/L。结论:餐厨垃圾高温菌种对斑马鱼有一定毒性,该研究为餐厨垃圾高温菌种的安全合理使用提供了科学依据。     

辽河保护区干流水体生物毒性诊断与评价

测定了斑马鱼(Danio rerio)急性和慢性毒性,结合水质综合指数分析,对辽河保护区干流水体健康进行了诊断。结果表明:斑马鱼成鱼及幼鱼的存活率超过50%,鱼卵的孵化率超过50%,说明水体生物毒性较低;水体pH、COD、BOD5与斑马鱼成鱼、幼鱼存活率、鱼卵孵化率之间呈显著的负相关关系(P0.05),说明水体中pH、COD和BOD5对斑马鱼成鱼、幼鱼及其鱼卵的发育影响较大;水质综合指数评价表明,一统河断面为国家Ⅴ类水质,其他各断面均达到国家Ⅳ类水质标准。     

迷迭香酸对硫酸铜致斑马鱼胚胎毒性的抑制作用

本文探讨硫酸铜(CuSO_4)对斑马鱼(Danio rerio)胚胎发育的毒性效应,使用迷迭香酸(RA)抑制CuSO_4对斑马鱼胚胎发育的毒性并探讨其作用机制。收集受精后1 h(1 hpf)的斑马鱼胚胎暴露于不同浓度的CuSO_4溶液,或含有不同浓度迷迭香酸的CuSO_4溶液,对照组培养在E3培养液中,观察胚胎死亡、孵化及畸形情况,计算胚胎死亡率、孵化率和畸形率;以活性氧(ROS)荧光探针DCFH-DA染色法检测迷迭香酸保护下胚胎的活性氧水平。对实验数据进行方差分析。结果显示:(1)CuSO_4浓度超过一定量时能诱导斑马鱼胚胎死亡和畸形,胚胎孵化率也降低。CuSO_4对96 hpf斑马鱼胚胎的半致死浓度(LC50)为7.7μmol/L,半致畸浓度(EC50)为1.9μmol/L。(2)在96 hpf,迷迭香酸与8μmol/L CuSO_4共同处理组斑马鱼胚胎的死亡率明显降低,孵化率升高。迷迭香酸与1.6μmol/LCuSO_4共同处理组斑马鱼胚胎的畸形率降低。(3)CuSO_4单独处理组的活性氧含量明显高于迷迭香酸与CuSO_4共同处理组和对照组。结果表明,CuSO_4暴露对斑马鱼胚胎发育的毒性效应可能与活性氧升高导致的氧化应激相关;迷迭香酸抑制CuSO_4对斑马鱼胚胎发育的毒性作用,可能与减少活性氧生成有关。     

抚顺市工业废水生物毒性评价

潜在毒性效应指数(PEEP)综合了多种生物测试及生态毒性测试结果,是一种新的评价和比较工业废水潜在毒性的指标,是理化分析评价法的一个重要补充。用蚕豆微核试验、发光细菌急性毒性试验、鱼类急性毒性试验逐一单项分析评价了抚顺市10家典型企业11个排水口废水的生物毒性。结果表明,抚顺工业废水大部分处于中度污染,农药厂、啤酒厂废水的毒性较高,而且这些企业的污水量相对少,迫切需要治理。并采用PEEP综合分析了废水的生物毒性程度,根据控制排放标准规定,PEEP>6时,要对企业排放废水实施控制措施。抚顺市10家典型污染企业废水PEEP均大于6,说明这10家企业都需要进一步控制废水排放及污染问题。     

五氯酚对斑马鱼胚胎的毒性效应研究

采用斑马鱼胚胎发育技术,对环境激素类物质五氯酚的毒性进行测定,结果表明,五氯酚(PCP)对胚胎的特定作用时间段是卵产出至发育6 h之内;PCP对胚胎发育有明显的抑制作用,会造成胚胎发育的畸形或死亡,不同时间染毒产生的可观察毒理学终点各异;随着PCP对发育48 h斑马鱼胚胎作用时间的减短,其致死效应敏感性降低,其中0 hpf组的LC50值最小,为70.8 μg·L^-1,24 hpf组LC50值最大,为831.8 μg·L^-1;斑马鱼胚胎对孵化后0时染毒的PCP最为敏感,PCP对胚胎产生急性毒性效应的敏感指标：心胞囊肿、血液循环障碍、无心律＞孵化率降低＞停滞发育作用;斑马鱼胚胎最敏感的指标为48 h血液循环障碍和48 h半致死效应.     

双酚A对斑马鱼肝脏和性腺的作用

为了阐明内分泌干扰物双酚A(BPA)对水生动物的毒理作用机制,本文研究了BPA对斑马鱼急性毒性及组织学损伤作用。结果表明:BPA对斑马鱼具有急性毒性效应,96h半致死浓度为6.3mg·mL-1,96h暴露对斑马鱼的肝脏产生了浓度依赖性损伤;在高浓度组,精巢结构损伤,卵泡萎缩严重(闭锁率35%);在0.2mg·mL-1亚致死浓度BPA组中,暴露96h后,斑马鱼肝脏受到轻微损伤,性腺组织结构没有受到明显损伤,卵巢中处于第Ⅲ时相晚期和第Ⅳ时相配子数比率增加,单个卵母细胞直径增加(P0.05);在2mg·mL-1亚致死浓度BPA组中,暴露96h,斑马鱼的肝脏组织受到了一定损伤,细胞核萎缩变形,细胞肿胀,核固缩,性腺组织受损不明显,卵巢中第Ⅲ时相晚期和第Ⅳ时相配子数比率有所增加;在6.1mg·mL-1BPA组中,暴露96h,斑马鱼肝脏产生了极大的损伤,细胞空泡化,大面积的组织坏死,空洞产生,精巢组织结构受到一定损伤,卵巢中发现大量细胞萎缩现象;BPA对斑马鱼肝脏具有靶器官毒性,对性腺作用值得进一步研究。     

Entwicklungsgeschichte und Ultrastruktur von Pollenkitt und Exine bei nahe verwandten entomophilen und anemophilen Angiospermensippen derAlismataceae,Liliaceae, Juncaceae,Cyperaceae, Poaceae undAraceae

Some closely related members of the monocotyledonous familiesAlismataceae, Liliaceae, Juncaceae, Cyperaceae, Poaceae andAraceae with variable modes of pollination (insect- and wind-pollination) were studied in relation to the ultrastructure of pollenkitt and exine (amount, consistency and distribution of pollenkitt on the surface of pollen grains). The character syndromes of pollen cementing in entomophilous, anemophilous and intermediate (ambophilous or amphiphilous) monocotyledons are the same in principal as in dicotyledons. Comparing present with former results one can summarize: 1) The pollenkitt is always produced in the same manner by the anther tapetum in all angiosperm sub-classes. 2) The variable stickiness of entomophilous and anemophilous pollen always depends on the particular distribution and consistency of the pollenkitt, but not its amount on the pollen surface. 3) The mostly dry and powdery pollen of anemophilous plants always contains a variable amount of inactive pollenkitt in its exine cavities. 4) A step-by step change of the pollen cementing syndrome can be observed from entomophily towards anemophily. 5) From the omnipresence of pollenkitt in all wind-pollinated angiosperms studied one can conclude that the ancestors of anemophilous angiosperms probably have been zoophilous (i.e. entomophilous) throughout.

     

Identification and Characterization of the First Equine Parainfluenza Virus 5

正Dear Editor,Parainfluenza virus 5 (PIV5), known as canine parainfluenza virus in the veterinary field, is a negative-sense,nonsegmented, single-stranded RNA virus belonging to the Paramyxoviridae family (Chen 2018). The virus was first reported in primary monkey kidney cells in 1954 (Hsiung1972), then it has been frequently discovered in various     

Pathogenic Characterization and Full Length Genome Sequence of a Reassortant Infectious Bursal Disease Virus Newly Isolated in Pakistan

<正>Dear Editor,Infectious bursal disease (IBD) is one of the most important diseases of the poultry. The IBD virus (IBDV), a nonenveloped virus belonging to the Birnaviridae family with a genome consisting of two segments of double-stranded RNA (segments A and B), targets B lymphocytes of bursa of Fabricious leading to immunosuppression. In Pakistan,poultry farming is the second biggest industry and IBD is the second biggest disease threating the poultry sector.However, there is limited genome information of IBDV     

Similar aerosol emission rates and viral loads in upper respiratory tracts for COVID-19 patients with Delta and Omicron variant infection

Highlights
1 Aerosol emission rates of Delta or Omicron patients were similar.
2 Viral loads in upper respiratory tract of Alpha, Delta and Omicron patients were similar.
3 Viral loads in upper respiratory tract of vaccinated or unvaccinated Delta patients had no difference.     

Recombinant human interferon-α1b inhibits SARS-CoV-2 better than interferon-α2b in vitro

Highlights
1) A comprehensive evaluation method for anti-SARS-CoV-2 drugs was established based on RT-qPCR, TCID₅₀ method, and immunofluorescence.
2) A significant antiviral effect of rHuIFN-α1b was shown with EC₅₀=0.12 IU/mL in Vero cells and EC₅₀=0.52 IU/mL in Calu-3 cells, which was better than rHuIFN-α2b (EC₅₀=0.25 IU/mL in Vero cells and EC₅₀=2.48 IU/mL in Calu-3 cells).
3) rHuIFN-α1b has a good potential in the application of anti-COVID-19 therapy.     

Continued antigenic variation of highly pathogenic avian influenza A (H7N9) virus in laying hens in China, 2020–2021

Highlights
1. 13 strains of H7N9 viruses from laying hens in 2020 and 2021 were identified.
2. H7N9 viruses in China comprised at least 11 genotypes.
3. H7N9 viruses are high pathogenic in chickens, not in ducks.
4. The most H7N9 viruses cross-reacted poorly with H7-Re3 antiserum.
5. The H7-Re3 vaccine was unable to prevent H7N9 infection.