马兜铃水提液对斑马鱼胚胎的致畸作用和心脏毒性的研究

目的：探索马兜铃水提液对斑马鱼胚胎的致畸作用和心脏毒性.方法：分别用不同浓度的马兜铃水提液和马兜铃酸A（AA）处理斑马鱼胚胎,观察致畸作用和对心脏发育影响.结果：给药组的斑马鱼胚胎出现畸形和死亡;当水提液中AA含量为0.5 μg/mL时,胚胎心率明显减慢;AA含量为5μg/mL时,胚胎在24～48 hpf之间全部死亡;水提液的LC50为1.43 μg/mL.结论：与AA相比,马兜铃水提液对斑马鱼胚胎有着更强的致畸和心脏毒性,且毒性作用具有时间和浓度依赖性.     

白消安在斑马鱼早期胚胎和幼鱼发育过程中的毒理和致畸作用

白消安(1,4-二甲磺酸丁酯)是目前在治疗慢性嗜中性粒细胞白血病和骨髓移植中使用最广泛的一种摄生体,因为它在临床上的重要作用,其胚胎毒性长期以来一直是医生们关注的焦点。本研究的目的是评估白消安在斑马鱼胚胎和幼鱼早期发育过程中的毒理作用,包括胚胎毒性和致畸效应。研究首先确定了白消安对斑马鱼胚胎和幼鱼的半致死浓度(LD50),在白消安/DMSO溶液中孵育24h的胚胎其LD50值为43.42μg·mL^-1, 幼鱼的LD50则为237.33μg·mL^-1;其次对白消安处理导致的形态学缺陷也进行了研究,主要包括钩形尾、无尾、脊椎弯曲、脊索波浪状扭曲、单胸鳍、围心包水肿、卵黄囊吸收延迟以及短体长;第三,利用阿利辛蓝(Alcian Blue)染色研究了颌骨和脊椎骨的异常发育,白消安处理过的幼鱼的麦克尔氏软骨(Meckel's cartilage)间的距离显著短于未处理过的阴性对照组,而处理组的幼鱼在脊椎骨的分化程度上也明显低于对照组;另外,为了研究白消安对斑马鱼生殖系统的影响,使用生殖细胞特异性的nanos1 cRNA探针标定斑马鱼原始生殖细胞,研究处理前后原始生殖细胞的增殖和迁移状况,发现暴露在40μg·mL^-1的白消安/DMSO溶液中12h,不仅能够抑制原始细胞的增殖而且明显干扰了这些细胞的定向迁移。这种对细胞的迁移作用之前从未见诸报道,其机制需要进一步地深入研究。     

应用水螅再生试验初探杜仲等中药的致畸作用

目的：探索三种安胎中药-杜仲、黄芩、苎麻根的发育毒性。方法：利用成体水螅与胃区体水螅形态学变化、中效中毒浓度与中效再生抑制浓度的比值(T50／I50)及Wilby评价标准,初步研究杜仲、黄芩、苎麻根的致畸作用。结果：致畸效用评价实验中,杜仲、黄苓、苎麻根的T50／I50比值分别为0．9、3．2、1．9,并呈剂量-反应关系;抗秋水仙碱抑制细胞分化实验中,杜仲还真有拮抗秋水仙碱对胃区体水螅分化再生的抑制作用,并呈较好的剂量-反应关系。结论：杜仲显示致畸作用阴性,有促进水螅分化及拮抗秋水仙碱抑制分化的作用;黄芩为致畸作用明显物质;苎麻根则显示致畸作用阳性。     

葡萄糖对胚胎发育的致畸作用研究

研究发现妊娠糖尿病是影响胚胎发育的重要致畸因素之一,患糖尿病孕妇的胎儿发生先天畸形风险性较非糖尿病孕妇胎儿高3-5倍,糖尿病妊娠导致心血管系统、神经系统的先天畸形严重影响胎儿及新生儿的生存质量。本实验分离孕9．5d的SD大鼠胚胎,采用体外全胚培养技术研究葡萄糖对胚胎发育的影响。实验分组：1．正常对照组,     

视黄类受体与视黄酸致畸作用关系

视黄酸（维甲酸）可引起包括人在内的多种动物胚胎畸形,其生物活性是由一系列视黄酸受体及其配体介导的。其中视黄类受体RAR起主要作用,RAR的配体为强致畸物,相对致畸活性由强至弱依次为配体α、配体β和配体γ。视黄酸受体RXR的配体无致畸活性,但是可加强RAR激动剂的某些致畸郊应。视黄酸受体还可通过其它基因的表达而影响胚胎发育。对视黄类受体基因突变和不同视黄类受体及其配体与致畸作用的关系,以及此类受体对其它基因表达的调节作简要综述。 Abstract: Retinoic acid can induce teratogenesis of the fetus of many animals including human, and its biological activities are induced by a serious of different retinoic acid accepters and their ligands. The retinoic acid acceptor RAR plays key roles in the teratogenesis, and the legands of RAR are strong teratogens. The intensity sequence of the relative teratogenesis is ligandα、ligandβ and ligandγ. The ligands of the retinoic acid acceptor RXR cannot induce teratogenesis, but they can enhance the teratogenesis of the RAR stimulus. The retinoic acid acceptors can also affect the development of the fetus by adjusting the expression of the other genes. The relations between the gene mutation of the retinoic acid acceptor, various retinoic acid acceptors and their ligands and teratogenesis of retinoic acid are summarized in this article. In addition, the regulations of the retinoic acid acceptors to the other genes are also discussed.     

氯丙嗪在斑马鱼胚胎和早期幼鱼发育过程中的神经毒性作用

目的 采用模式动物斑马鱼作为研究对象,观察氯丙嗪（chlorpromazine,CPZ）暴露对胚胎和幼鱼早期神经发育的影响.方法 在一般毒性评价的基础上,通过整体胚胎细胞凋亡检测和脑组织病理学检查,了解CPZ对神经发育的器质性改变;采用神经行为学方法,包括幼鱼触动逃避反应、自发运动以及惊恐逃避反射等,研究氯丙嗪暴露所致的神经发育功能性障碍.结果斑马鱼胚胎受精后6 h（6 hpf）～72 hpf暴露于CPZ（≥5 mg/L）可引起胚胎和幼鱼死亡、致畸和幼鱼孵化延迟,并呈浓度和时间依赖性;采用吖啶橙染色检测36 hpf整体胚胎凋亡细胞,发现凋亡细胞主要集中在胚胎中脑、后脑、丘脑以及中后脑连接区、脊索和尾部等处;脑组织病理学检测发现,7dpf幼鱼颅腔增大、脑体积减小、脑细胞缩小且细胞间隙增宽.6～72 hpf CPZ（≥0.0625 mg/L）暴露后,幼鱼神经行为学研究发现,CPZ（≥0.125 mg/L）可引起3dpf幼鱼触觉运动能力下降;CPZ（≥0 5 mg/L）可浓度依赖性地抑制幼鱼自发运动,并出现僵直不动、震颤或快速刻板式转圈运动等行为改变;光惊恐实验中,暗环境下各暴露组幼鱼对突发强光刺激均表现为惊跳逃避,并且暗-光交替期运动加速度变化与对照组无显著差异;在撤除光源后,1mg/L和2 mg/L暴露组幼鱼暗适应时程缩短,而0.125 mg/L和0.25 mg/L暴露组暗适应时程延长,提示CPZ对外界刺激引发的幼鱼活跃游动有抑制和促进双重毒性作用.结论 CPZ暴露对斑马鱼胚胎和幼鱼具有明显的神经发育毒性作用.模式动物斑马鱼作为一种高通量筛选模型在外源性化合物神经发育毒性评价中具有较好的应用前景.     

香烟白酒浸出液对Wistar大鼠身体健康影响的探究

通过学生自己设计实验探讨香烟的白酒浸出液对Wistar大鼠体重变化、毛色、肝指数（肝重占体重的百分数）、肝脏病变、对外界刺激的反应、嗜睡情况、死亡情况、血清总胆固醇（TC）、血清总甘油三酯（TG）、天门冬氨酸氨基转氨酶（AST）、丙氨酸氨基转氨酶（ALT）等方面的影响,激发学生创新意识,培养学生创新能力,帮助他们寻求科学的探究方法。并对全校学生进行戒烟戒酒的宣传教育。     

被子植物雌雄配子及早期胚胎的分离与研究应用

被子植物的有性生殖过程复杂精巧并深藏于母体组织内进行,一直以来难以对该过程进行直接的细胞学和分子生物学研究。如今在多种植物中获得了有活力而无污染的配子细胞和早期胚胎,结合少量细胞m RNA提取技术、基因组深度测序以及离体授精系统等技术,人们已能对被子植物受精过程中的配子识别、配子融合、合子激活等重要发育事件进行深入分析。本文对有代表性的被子植物配子和早期胚胎的分离技术及其在受精作用研究中的应用、存在的问题和前景进行了总结,旨在为植物生殖发育研究提供帮助。     

Effects of Cigarette Smoke Extracts on the Growth and Senescence of Skin Fibroblasts In Vitro

Epidemiological studies have shown that cigarette smoke (CS), a very common environmental factor, plays an important role in skin aging. Although some in vivo studies have suggested that CS affects skin aging, the detailed effects of CS on skin cells in vitro remain largely unknown. In this study, we investigated the effects of cigarette smoke extract (CSE) on the growth, proliferation, and senescene of skin fibroblasts and the possible mechanism underlying these effects. Primary cultured human fibroblasts were exposed to a range of concentrations of CSE. Cell viability and cell proliferation after CSE exposure were analyzed with the methyl thiazolyl tetrazolium (MTT) assay and bromodeoxyuridine incorporation assay, respectively. Growth curves of fibroblasts exposed to different concentrations of CSE were developed and prolonged CSE-exposed cells were observed. Morphological and ultrastructural changes in fibroblasts were assessed by inverted light microscopy and transmission electron microscopy (TEM). Dying cells were stained with senescence-associated β-galactosidase (SA β-gal). Intracellular reactive oxygen species (ROS) levels, superoxide dismutase (SOD) activity, and glutathione peroxidase (GSH-Px) activity were determined by a colorimetric method. We found that proliferative capacity and growth were inhibited by CSE exposure in a dose- and time-dependent manner. Fibroblasts exposed to even low concentrations of CSE for a long period of time (5 passages) showed significantly increased SA β-gal activity and typical features of aging cells. Meanwhile, CSE inhibited superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities and augmented ROS levels. Our observations suggest that CSE exposure impairs fibroblast growth and proliferation and leads to features similar to those seen in senescent cells. Oxidative stress injury and inhibition of antioxidant defense activity may be involved in CSE-induced fibroblast senescence.     

高温诱导金黄仓鼠胚神经上皮细胞基因的差异表达

以mRNA差异显示法研究高温作用后金黄仓鼠胚神经上皮细胞基因的差异表达。结果表明,高温处理后第16h,从鼠胚神经上皮细胞基因表达中检出两条良好重复性差异序列。该差异序列为未知序列,属新EST,提示高温可能诱导金黄仓鼠胚神经上皮细胞基因表达发生变化。     

Role of Hyperthermia in Effects of Electroconvulsive Shock on Protein Synthesis in the Rabbit

The effects of electroconvulsive shock (ECS) on rectal temperature (TR) and on protein synthesis in brain and liver were compared in rabbit, rat, and mouse. Protein synthesis status was assessed using an in vitro amino acid incorporation method which provides information equivalent to polyribosome profiles. In the rabbit, TR rose from 39.5 +/- 0.4 degrees C to 40.4 +/- 0.2 degrees C within 10 min following a single ECS, and significant hyperthermia persisted for at least 60 min. This effect was markedly attenuated in animals housed at 4 degrees C. In vitro protein synthesis activities of rabbit brain and liver preparations were significantly reduced following ECS only in those animals whose TR exceeded 40 degrees C. In the rat, ECS gave rise to a significant hyperthermia, but in no case did TR exceed 40 degrees C, and protein synthesis activity of brain supernatants was not affected. In the mouse, ECS reduced TR and had no effect on in vitro protein synthesis activity. These results demonstrate that the unique sensitivity of protein synthesis in rabbit tissues to electroconvulsive shock is a direct consequence of the hyperthermia that arises following ECS in this species.     

Analysis of Hydrogen Peroxide in an Aqueous Extract of Cigarette Smoke and Effect of pH on the Yield

An analysis of hydrogen peroxide in an aqueous extract of cigarette smoke, which contains many redox-active compounds, requires a method with high selectivity. An aqueous extract of the particulate phase of cigarette smoke was analyzed by HPLC with an electrochemical detector (ECD). Samples were prepared by collecting the particulate phase of the cigarette smoke on a glass fiber filter and extracting it with a phosphate buffer. The obtained solution was purified by using a Waters Oasis MCX cation-exchange cartridge, and then analyzed by an HPLC-ECD system with a Shodex KS-801 mixed-mode resin column. Pre-injecting hydrogen peroxide at a high concentration into the HPLC instrument stabilized the analytical results. The recovery of hydrogen peroxide by using an extract of the particulate phase of the cigarette smoke was more than 80%. An increase in the amount of hydrogen peroxide was observed during extraction with the phosphate buffer at higher pH values. In contrast, extraction with phosphoric acid did not increase the amount of hydrogen peroxide during extraction.     

高温对原代支持细胞增殖能力和occludin紧密连接蛋白的影响

目的:研究高温对原代大鼠睾丸支持细胞增殖作用和对紧密连接蛋白的损伤机制.方法:体外分离培养雄性Wistar大鼠睾丸支持细胞(Sertoli cell,SC),免疫组化FasL鉴定.实验分为对照组(36℃)和实验组(37℃、38℃、39℃).在相应的温度下培养5d后,CCK-8法检测SC增殖作用,Western印迹法检测OCLN表达水平.结果:体外培养SC的纯度＞90％,CCK-8结果显示,细胞增殖活性在36℃时最强,37～39℃时逐渐降低;Western印迹显示,36℃时OCLN表达量最高;高于36℃时,OCLN表达量随着温度的增加而降低(P＜0.05).结论:高温影响SC增殖活性,破坏了支持细胞紧密连接蛋白的正常表达和血睾屏障的完整性,从而影响正常精子的形成.     

In vitro Culture of Early Rabbit Embryos Injected with Foreign Gene and Its Retention

Fertilized rabbit eggs injected with SMTPGH gene were cultured in vitro and retention of theinjected gene was studied using PCR technique and nonradioactive labelling methed. In a mediumof TC199 + 10% FCS, three quarters of the fertilized eggs developed to the blastocyst stage. Noapparent change of the injected gene was found before the 8-cell stage, after which it was eitherintegrated into the chromosome of the host or lost gradually. But finally, the retention rate of theinjected gene should be equal to its integration rate.     

Effects of p,p''-DDT on the Rat Brain Concentrations of Biogenic Amine and Amino Acid Neurotransmitters and Their Association with p,p''-DDT-Induced Tremor and Hyperthermia

Male, Fischer strain 344 adult rats were given various doses (25-100 mg/kg) of p,p'-DDT by oral gavage, and levels of biogenic amines, their metabolites, and amino acid neurotransmitters, tremor activity, and rectal temperature were measured at several intervals (2, 5, 12, and 24 h) after dosing. Dose-related increases in rectal temperature and in tremor activity were observed at 50-100 mg/kg 12 h after dosing. Tremorigenic doses of DDT increased the 5-hydroxyindoleacetic acid (5-HIAA) level in hypothalamus, brainstem, and striatum, whereas doses of 75 and 100 mg/kg increased the 3-methoxy-4-hydroxyphenylglycol (MHPG) level in hypothalamus and brainstem and the 3,4-dihydroxyphenylacetic acid level in striatum. Six amino acids were assayed in the brainstem, hypothalamus, and striatum; aspartate and glutamate levels were increased only in brainstem at 25-100 mg/kg. No consistent changes in concentrations of taurine, glutamine, glycine, or gamma-aminobutyric acid were observed in any of the regions assayed. Time-related increases in rectal temperature were seen 2-12 h after dosing, and the presence of tremor was observed 5-12 h after dosing; for both the time of peak effect was at 12 h. The DDT-induced hyperthermia and tremor were associated with dose- and time-related increases in levels of 5-HIAA, MHPG, aspartate, and glutamate. It is suggested that an increase in the turnover rate of 5-hydroxytryptamine (5-HT) may be responsible for the DDT-induced hyperthermia, whereas increases in the metabolism of 5-HT and norepinephrine may be involved in the tremor.     

葡萄糖对ICR小鼠胚胎体外发育的影响

研究葡萄糖在小鼠早期胚胎体外发育中的作用。实验1将6—8周龄的ICR雌鼠超数排卵后与公鼠交配,收集1-细胞放入含0(对照组)、0.5、1、3、5、10mmol/L葡萄糖的CZB中培养;实验2将从超排的ICR雌鼠输卵管内收集的1-细胞放入无糖CZB中培养,分别于1细胞、2细胞、4细胞、桑椹胚阶段移入含3.0mmol/L葡萄糖(最适浓度)的CZB中,培养24h后又移回到无糖CZB中(桑椹胚阶段除外)继续培养以及整个胚胎培养过程均在含糖CZB中,对照组胚胎培养全程均在无糖CZB中。每组胚胎于37℃、5%CO2培养箱中培养120h,每24h在倒置显微镜下观察胚胎发育情况,分别计算2-细胞率、4-细胞率、桑椹胚率、囊胚率和孵化率,并进行囊胚细胞计数。结果显示,小鼠胚胎在含糖CZB中与在无糖CZB中4-细胞发育率无差异;含糖CZB中囊胚率显著高于对照组;3.0mmol/L浓度组囊胚细胞数显著高于其余组;2-细胞至4-细胞、4-细胞至桑椹胚前添加葡萄糖囊胚率显著高于对照组,1-细胞至2-细胞、桑椹胚及其以后阶段添加葡萄糖囊胚率与对照组无差异。实验证实,在ICR小鼠胚胎体外培养中加入葡萄糖不会导致2-细胞阻滞;葡萄糖浓度增至10mmol/L对ICR小鼠胚胎无毒性作用;ICR小鼠胚胎体外培养的最适葡萄糖浓度为3.0mmol/L;2-细胞至4-细胞、4-细胞至桑椹胚前添加葡萄糖是必要的。     

石硖龙眼未成熟种子种胚的萌发及成苗的研究

以花后82～87 d的石硖龙眼(Dimocarpus longan Lour.‘Shixia’)未成熟果实在4℃贮藏24 h,研究种子与种胚的萌发与成苗情况。结果表明:河沙直播未成熟胚的最终成苗率达到80%,远高于离体培养未成熟种子的最终成苗率(12.63%～44.03%);虽然4℃的低温贮藏略为推迟了河沙直播未成熟胚的萌发时间,但对最终成苗率及幼苗生长的影响不大,这对龙眼杂交育种中未成熟种子种胚的挽救具有较好的应用价值。