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1.
乙醇对胚胎发育与卵黄囊超微结构的影响   总被引:2,自引:0,他引:2  
为研究发育敏感期暴露于乙醇不同时间对胚胎发育和胚胎卵黄囊超微结构的影响 .以体外全胚胎培养和电镜技术研究 0 .2g·L- 1乙醇不同时间作用时对胚胎发育影响及胚胎卵黄囊超微结构改变 .结果表明发育异常与乙醇作用存在时间 效应关系 .0 .2g·L- 18h对胚胎发育和形态分化无明显影响 ,随时间延长除胚胎头长 ,体长 ,卵黄囊直径 ,蛋白质和DNA含量等主要发育指标进一步受抑制外 ,胚胎畸形 ,死亡率明显升高 .卵黄囊超微结构变化程度与染毒时间和胚胎发育状况相一致 ,乙醇可导致卵黄囊细胞内微绒毛和溶酶体数量减少 ,线粒体等部分细胞器内膜肿胀 .上述结果提示卵黄囊结构损伤和破坏在乙醇所致的发育异常中起重要作用  相似文献   

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目的 为探讨铝的发育毒性及机理。方法孕 9.5d大鼠胚胎于体外培养系统中给予不同剂量的硫酸铝 ,培养 4 8h后 ,观察胚胎生长发育和器官形态分化状况 ;应用二硫代双硝基苯甲酸 (DTNB)直接法测定胚胎组织谷胱甘肽 (GSH)含量 ;以 1,6 二苯己三烯为荧光探剂 ,用荧光偏振技术测定卵黄囊细胞膜脂质流动性。结果 当培养液中铝浓度为1.2mg·L- 1时 ,胚胎生长发育和分化明显被抑制 ;3.0mg·L- 1时 ,畸形胚胎发生率明显升高 ,主要有神经管闭合不全 ,脑发育不良和体翻转不全 ;6 .0mg·L- 1时 ,胚胎组织GSH含量和卵黄囊细胞膜脂质流动性显著降低。上述效应均呈现出一定的剂量 效应 (反应 )关系。结论 铝有潜在的致畸性和胚胎毒性 ,胚胎组织GSH含量和卵黄囊细胞膜流动性降低可能在铝致胚胎发育毒性中起重要作用  相似文献   

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目的探讨生草乌对胚胎发育的毒性作用及机制。方法应用大鼠着床后体外全胚胎培养模型,将9.5dSD大鼠胚胎与含不同浓度生草乌的大鼠即刻离心血清共培养48h,观察其对大鼠胚胎生长发育和组织器官形态分化的影响。生草乌终浓度分别为:0、0.63、1.25、2.5和5mg生药/ml。结果随着生草乌剂量增加,胚胎生长发育和器官分化的各项指标均呈现下降趋势,有一定的剂量-效应关系。生草乌最大无作用剂量为1.25,2.5mg/ml以上剂量可诱发卵黄囊生长和血管分化不良、生长迟缓及形态分化异常,严重者出现体节紊乱、小头、心脏发育迟滞(心小,停留在心管期)及心脏空泡等。结论较高剂量生草乌对体外培养大鼠胚胎具有一定的毒性作用,建议孕妇妊娠期间(特别是妊娠前3个月)慎用或禁用草乌。  相似文献   

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目的探讨新型消毒剂三氯异氰尿酸(TCCA)对斑马鱼胚胎及幼鱼的发育毒性。方法选择受精后2 h的斑马鱼胚胎进行染毒:①将胚胎置于含有TCCA 50,100,150,200,250和300 mg·L~(-1)的培养液中暴露48 h,检测半数致死浓度(LC_(50))。②将胚胎置于含有TCCA 0,10.4,20.8和41.7 mg·L~(-1)的培养液中暴露96 h,分别于暴露后48,72和96 h检测胚胎死亡率、畸形率和心率,采用羟胺法于暴露后2,4和6 h检测胚胎组织超氧化物歧化酶(SOD)的活性,HE染色观察暴露后7 d幼鱼头部组织病理结构。结果 TCCA暴露48 h,斑马鱼胚胎LC_(50)为166.9 mg·L~(-1)。与正常对照组相比,暴露后96 h,TCCA 41.7 mg·L~(-1)组斑马鱼胚胎死亡率和畸形率显著升高(P<0.05),TCCA各剂量组心率显著下降(P<0.05);暴露后72h,TCCA41.7mg·L~(-1)组死亡率显著升高(P<0.05),20.8和41.7mg·L~(-1)组畸形率显著升高(P<0.05),心率显著下降(P<0.05);暴露后48 h,TCCA 41.7 mg·L~(-1)组畸形率显著升高(P<0.05)、心率显著下降(P<0.05)。TCCA暴露4和6 h,20.8和41.7 mg·L~(-1)组SOD活性较正常对照组显著下降(P<0.05)。TCCA暴露7 d后,与正常对照组相比,各浓度组斑马鱼幼鱼均出现脑和眼部间隙变大及眼部视网膜分层不明显的病理改变。结论 TCCA对斑马鱼胚胎发育有毒性作用,能引起胚胎发育早期SOD活性下降,造成幼鱼视网膜组织结构损伤。  相似文献   

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褪黑素对苯妥英所致小鼠胚胎体外致畸效应的拮抗作用   总被引:4,自引:1,他引:3  
采用体外着床后全胚培养模型研究苯妥英诱发的胚胎脂质过氧化和形态异常 ,确定褪黑素 (MT)的胚胎保护作用 .d 8.5的小鼠胚胎经苯妥英单独或与MT联合作用 4 8h后测定胚胎生长 ,形态发育 ,全胚蛋白质含量及脂质过氧化产物 .结果表明苯妥英导致胚胎生长发育迟滞并诱发脂质过氧化产物增高 4倍 .MT 1mmol·L- 1有轻微生长抑制作用 ,但可完全拮抗苯妥英诱发的脂质过氧化作用 ,并降低或完全拮抗苯妥英导致的形态生长发育异常 .表明MT有拮抗苯妥英胚胎致畸效应的作用  相似文献   

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目的以斑马鱼胚胎为模型,探讨一种高效氯氰菊酯β-氯氰菊酯对胚胎发育的影响。方法 丙酮为助溶剂,配制β-氯氰菊酯0.05,0.1,0.15,0.2,0.6和1 mg.L-1,采用换水式每12 h更换一半β-氯氰菊酯溶液,对斑马鱼胚胎进行96 h暴露处理,采用显微镜观察β-氯氰菊酯0.05,0.1,0.15,0.2,0.6和1 mg.L-1对斑马鱼胚胎发育形态,测定受精后24 h(24 hpf)自主抽动次数、48 hpf心率及孵化率、72和96 hpf体轴弯曲个体比例等。结果 与正常对照组比较,β-氯氰菊酯0.05,0.1,0.15,0.2,0.6和1 mg.L-1组斑马鱼胚胎在24 hpf前形态上未出现明显异常,48 hpf以后表现出体轴弯曲、心包囊肿等不同程度的毒性反应症状,β-氯氰菊酯0.2 mg.L-1组幼鱼胸鳍发育即受到严重抑制且黑色素减少体色偏黄;随着β-氯氰菊酯浓度的增加,斑马鱼胚胎在24 hpf时每分钟自主抽动次数由正常对照组的(0.72±0.19)次增加至(3.83±1.07)次(P<0.05);48 hpf孵化率由对照组的(15.5±4.3)%升高至(98.9±1.2)%(P<0.05)。β-氯氰菊酯0.05 mg.L-1组72 hpf和96 hpf体轴弯曲个体比例分别为6.6%和10%,β-氯氰菊酯1 mg.L-1组分别为97.8%和100%。结论 β-氯氰菊酯对斑马鱼胚胎的神经及形态发育均有明显抑制作用,并且呈现一定的时间剂量依赖性。  相似文献   

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哺乳动物植入后全胚胎培养排除了母体等因素对胚胎发育的影响 ,并可人为控制实验条件 ,与组织、细胞培养及动物整体实验相比 ,具有许多明显的优点 ,可动态观察和研究药物致畸作用及机制。细胞凋亡是多细胞生物体内环境稳定和发育精确控制的基本条件 ,也是胚胎发生和发育过程中一定结构和功能器官形成的必要条件 ,过多的细胞凋亡或不适当的细胞凋亡最终导致先天性畸形的发生[1 ] 。本研究利用小鼠全胚胎培养方法观察了抗肿瘤药物环磷酰胺致畸作用 ,在获得畸形胚胎的基础上 ,对环磷酰胺致畸作用与细胞凋亡的关系进行了探讨。1 材料与方法1 1…  相似文献   

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目的以致胚胎毒性阳性药物全反式维甲酸(ATRA)及丙戊酸钠进行斑马鱼胚胎发育毒性试验,建立有效的斑马鱼胚胎发育毒性评价方法。方法采用水浴染毒法,将受精后2h(2hpf)的斑马鱼胚胎暴露于不同浓度梯度的阳性约物。分别在24、48、72和144hpf观察并记录畸形及死亡的胚胎数目。统计阳性药物的EC50和LG50,计算致畸指数(TI=LC50/EG50)。结果两种阳性药物所致斑马鱼胚胎发育早期(24~48hpf)与发育后期(72~144hpf)的畸形表现不同。在72hpf,两种阳性药物对胚胎孵化率均有明显抑制作甩144hpf可见ATRA(≥1.6×10^-3mg/L)和丙戊酸钠(≥1.25×10^2mg/L)严晕致畸作用,T1分别为10.35和5.72。两种阳性药物胚胎敛畸率及死亡率均呈明显的浓度依赖关系,且与已有动物试验及体外试验结果相符。结论以两种阳性药物建立有效的斑马鱼胚胎发育毒性评价方法,可进行进一步的验证。  相似文献   

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目的 设计合成菲并咪唑衍生物L271,并研究其外抗肿瘤活性,及其对斑马鱼胚胎发育的毒性效应.方法 以1,10-邻菲啰啉-5,6-二酮和2-甲基苯甲醛为原料,运用微波辅助合成技术制备了菲并咪唑衍生L271.采用噻唑蓝(MTT)比色法研究菲并咪唑衍生物L271对人宫颈癌细胞Hela和人肺腺癌细胞A549在体外生长的抑制作用.以斑马鱼为模型,研究L271对斑马鱼胚胎发育的形态、孵化率、死亡率和畸形率的影响,评价L271对斑马鱼胚胎发育的毒性效应.结果 经电喷雾质谱技术(ESI-MS)表征确证成功合成了目标化合物L271.新合成的菲并咪唑衍生物L271对人宫颈癌细胞Hela和人肺腺癌细胞A549均有增殖抑制作用,尤其对人宫颈癌细胞Hela的IC50值达到(8.38±0.09)μmol/L,与同等条件下吡柔比星的抗肿瘤活性相当[IC50=(6.97±0.07)μmol/L].与对照组相比,L271浓度≥15μmol/L暴露组能够引起斑马鱼出现尾鳍萎缩、脊柱弯曲、卵黄囊水肿和心包囊水肿等畸形现象;L271浓度≥30μmol/L可显著降低斑马鱼的孵化率和提高死亡率(P<0.05);在48、72、96 hpf时,L271对斑马鱼胚胎半致死浓度LC5o分别是37.331μmol/L(95%CI:35.535-39.301)、34.911μmol/L(95%CI:33.213-36.729)、30.283μmol/L(95%CI:29.590-30.980);在L271浓度≥15μmol/L时,随着L271浓度的逐渐增加,各暴露组正常胚胎百分率渐下降,胚胎死亡率逐渐上升,而胚胎畸形率先升后降.结论 L271对人宫颈癌细胞Hela具有良好的抗肿瘤活性,且与吡柔比星的相当;L271浓度≤10μmol/L对斑马鱼胚胎发育无明显毒性效应.  相似文献   

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目的观察不同剂量高碘摄入对小鼠胚胎发育的影响,为评价高碘的生殖毒性提供理论依据。方法BABL/C小鼠195只,雌雄2∶1,按体重将动物随机分为6组,对照组45只动物,其它每组30只动物。通过饮水中给予不同剂量的高碘(1 5003、000、6 0001、2 000和24 000μg/L),4个月后合笼,观察长期高碘摄入对小鼠胚胎发育的影响。结果高碘组母鼠血清总四碘甲腺原氨酸(total tetraiodothyronine,TT4)水平升高,总三碘甲腺原氨酸(total triiodothyronine,TT3)水平降低,从3 000μg/L开始与对照组差异有统计学意义。平均胎盘重从3 000μg/L组以上均明显低于阴性对照组。高碘组的吸收胎率和死胎率明显升高,并且呈剂量-效应关系(r=0.167,P<0.05)。高碘组骨骼畸形发生率升高,从3 000μg/L开始差异有统计学意义,并且呈剂量-效应关系(r=0.80,P<0.05)。结论长期高碘摄入具有胚胎发育毒性,主要表现为胚胎的骨骼畸形。该实验条件下,高碘所致胚胎发育毒性的阈剂量为3 000μg/L(即0.75 mg/kg)。  相似文献   

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We report herein the condensation of 4,7-dichloroquinoline (1) with tryptamine (2) and D-tryptophan methyl ester (3) . Hydrolysis of the methyl ester adduct (5) yielded the free acid (6) . The compounds were evaluated in vitro for activity against four different species of Leishmania promastigote forms and for cytotoxic activity against Kb and Vero cells. Compound (5) showed good activity against the Leishmania species tested, while all three compounds displayed moderate activity in both Kb and Vero cells.  相似文献   

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Lung disease and PKCs   总被引:1,自引:0,他引:1  
The lung offers a rich opportunity for development of therapeutic strategies focused on isozymes of protein kinase C (PKCs). PKCs are important in many cellular responses in the lung, and existing therapies for pulmonary disorders are inadequate. The lung poses unique challenges as it interfaces with air and blood, contains a pulmonary and systemic circulation, and consists of many cell types. Key structures are bronchial and pulmonary vessels, branching airways, and distal air sacs defined by alveolar walls containing capillaries and interstitial space. The cellular composition of each vessel, airway, and alveolar wall is heterogeneous. Injurious environmental stimuli signal through PKCs and cause a variety of disorders. Edema formation and pulmonary hypertension (PHTN) result from derangements in endothelial, smooth muscle (SM), and/or adventitial fibroblast cell phenotype. Asthma, chronic obstructive pulmonary disease (COPD), and lung cancer are characterized by distinctive pathological changes in airway epithelial, SM, and mucous-generating cells. Acute and chronic pneumonitis and fibrosis occur in the alveolar space and interstitium with type 2 pneumocytes and interstitial fibroblasts/myofibroblasts playing a prominent role. At each site, inflammatory, immune, and vascular progenitor cells contribute to the injury and repair process. Many strategies have been used to investigate PKCs in lung injury. Isolated organ preparations and whole animal studies are powerful approaches especially when genetically engineered mice are used. More analysis of PKC isozymes in normal and diseased human lung tissue and cells is needed to complement this work. Since opposing or counter-regulatory effects of selected PKCs in the same cell or tissue have been found, it may be desirable to target more than one PKC isozyme and potentially in different directions. Because multiple signaling pathways contribute to the key cellular responses important in lung biology, therapeutic strategies targeting PKCs may be more effective if combined with inhibitors of other pathways for additive or synergistic effect. Mechanisms that regulate PKC activity, including phosphorylation and interaction with isozyme-specific binding proteins, are also potential therapeutic targets. Key isotypes of PKC involved in lung pathophysiology are summarized and current and evolving therapeutic approaches to target them are identified.  相似文献   

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This study explored gender-related symptoms and correlates of alcohol dependence in a crosssectional study of 150 men and 150 women with a lifetime diagnosis of alcohol use disorders (AUD). Participants were recruited in equal numbers from treatment settings, correctional centres and the general community. Standardized measures were used to determine participants' use of substances, history of psychiatric disorders and psychosocial stress, their sensation seeking and family history of substance use and mental health disorders. Multivariate analyses were used to detect patterns of variables associated with gender and the lifetime severity of AUD. Men had a longer history of severe AUD than women. Women had similar levels of alcohol dependence and medical and psychological sequelae as men, despite 6 fewer years of AUD. More women than men had a history of severe psychosocial stress, severe dependence on other substances and antecedent mental health problems, especially mood and anxiety disorders. There were differences in family history of alcohol-related problems approximating same-gender aggregation. The severity of a lifetime AUD was predicted by its earlier age at onset and the occurrence of other disorders, especially anxiety, among both men and women. The limitations in the generalizability of these findings due to sample idiosyncrasies are discussed.  相似文献   

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Class Cubozoa includes several species of box jellyfish that are harmful to humans. The venoms of box jellyfish are stored and discharged by nematocysts and contain a variety of bioactive proteins that are cytolytic, cytotoxic, inflammatory or lethal. Although cubozoan venoms generally share similar biological activities, the diverse range and severity of effects caused by different species indicate that their venoms vary in protein composition, activity and potency. To date, few individual venom proteins have been thoroughly characterised, however, accumulating evidence suggests that cubozoan jellyfish produce at least one group of homologous bioactive proteins that are labile, basic, haemolytic and similar in molecular mass (42-46 kDa). The novel box jellyfish toxins are also potentially lethal and the cause of cutaneous pain, inflammation and necrosis, similar to that observed in envenomed humans. Secondary structure analysis and remote protein homology predictions suggest that the box jellyfish toxins may act as α-pore-forming toxins. However, more research is required to elucidate their structures and investigate their mechanism(s) of action. The biological, biochemical and molecular characteristics of cubozoan venoms and their bioactive protein components are reviewed, with particular focus on cubozoan cytolysins and the newly emerging family of box jellyfish toxins.  相似文献   

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Invasive pulmonary aspergillosis (IPA) is a fungal disease of the lung associated with high mortality rates in immunosuppressed patients despite treatment. Targeted drug delivery of aqueous voriconazole solutions has been shown in previous studies to produce high tissue and plasma drug concentrations as well as improved survival in a murine model of IPA. In the present study, rats were exposed to 20 min nebulizations of normal saline (control group) or aerosolized aqueous solutions of voriconazole at 15.625 mg (low dose group) or 31.25 mg (high dose group). Peak voriconazole concentrations in rat lung tissue and plasma after 3 days of twice daily dosing in the high dose group were 0.85 ± 0.63 μg/g wet lung weight and 0.58 ± 0.30 μg/mL, with low dose group lung and plasma concentrations of 0.38 ± 0.01 μg/g wet lung weight and 0.09 ± 0.06 μg/mL, respectively. Trough plasma concentrations were low but demonstrated some drug accumulation over 21 days of inhaled voriconazole administered twice daily. Following multiple inhaled doses, statistically significant but clinically irrelevant abnormalities in laboratory values were observed. Histopathology also revealed an increase in the number of alveolar macrophages but without inflammation or ulceration of the airway, interstitial changes, or edema. Inhaled voriconazole was well tolerated in a rat model of drug inhalation.  相似文献   

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