底物中碳酸钙含量对太平洋牡蛎(Crassostrea gigas)幼虫附着的诱导效应

为探讨底物中钙含量对牡蛎幼虫附着的诱导效应,本研究设计2因子随机区组实验,检验底物碳酸钙含量(4个处理水平:5%、20%、40%和60%)和海水中牡蛎幼虫丰度(低处理组:1 ind·m L~(-1),高处理组:7~8 ind·m L~(-1))对实验底物上太平洋牡蛎(Crassostrea gigas)稚贝附着效果(密度和壳高)的影响。结果表明:钙含量和海水中牡蛎幼虫丰度均显著影响实验底物上附着牡蛎稚贝的密度(P0.05),钙含量对附着稚贝壳高的影响不显著(P0.05),幼虫丰度显著影响附着稚贝的壳高(P0.05);在相同牡蛎浮游幼虫丰度下,20%碳酸钙处理组对牡蛎幼虫附着的诱导能力最大,显著高于60%处理组(P0.05),5%和40%处理组的诱导能力介于中间;在碳酸钙含量相同情况下,高牡蛎幼虫丰度处理组中实验底物上牡蛎稚贝附着量显著高于低幼虫丰度处理组(P0.05),而平均壳高却表现为高幼虫丰度处理组低幼虫丰度处理组(P0.05)。     

铅胁迫对3种藓类植物抗氧化酶活性的影响

采用水培实验研究了重金属Pb对3种藓类植物尖叶拟船叶藓(Dolichomitriopsis diversiformis)、湿地匍灯藓(Plagiomnium acutum)和匍枝青藓(Brachythecium procumbens)的抗氧化酶(SOD、POD和CAT)活性的影响.结果表明,(1)在1~200 mg·L-1的铅胁迫浓度范围内,Pb对3种藓类植物的SOD活性均具有显著的促进作用,对Pb胁迫的种间敏感性差异为尖叶拟船叶藓>湿地匍灯藓>匍枝青藓;(2)POD活性对Pb胁迫的反应趋势有一定差别,尖叶拟船叶藓和匍枝青藓的POD活性随Pb浓度的增加先升后降,湿地匍灯藓的POD活性变化较为平缓,种间敏感性差异为匍枝青藓>尖叶拟船叶藓>湿地匍灯藓;(3)在100 mg·L-1时Pb对湿地匍灯藓CAT活性表现为显著促进作用外,其余在低浓度下显示无显著影响,在高浓度下表现为抑制效应,种间敏感性差异为尖叶拟船叶藓>匍枝青藓>湿地匍灯藓.3种藓类植物的抗氧化酶体系中对Pb胁迫的抵抗起关键作用的是SOD,可作为藓类植物受Pb胁迫的敏感生理指标.3种植物中对Pb胁迫的反应较为敏感的是尖叶拟船叶藓.     

沼蛤(Limnoperna fortunei)幼虫的附着行为特性

沼蛤(Limnoperna fortunei Dunker,1857),俗称淡水壳菜,是一种扩散能力与适应能力都较强的入侵性底栖动物,它对自然环境与输水工程的侵入和大规模附着,不仅会破坏当地的生物群落结构,而且沼蛤成贝在工程内稳定附着后难以去除,造成重大工程危害。通过试验研究沼蛤幼虫的附着行为特性,并利用该特性对原水中的幼虫进行吸引附着处理,以减少幼虫进入工程造成污损附着。选用前期研究推荐的沼蛤幼虫喜好附着的黄麻材料制成的附着排作为试验材料,设置5组附着排长度工况:1,3,5,6,8 m,在5组流量工况:3.1,5.7,6.7,9.6,12.1 L/s下开展试验,研究不同附着排长度和流量条件下沼蛤幼虫的附着行为,以便优选出吸附幼虫的最佳条件。试验结果表明:(1)黄麻材料的吸附效果与附着排长度呈正相关关系,材料长度为3—5m时,吸附率即可达到50%;材料长度为6—8 m时,平均效果为62—76%,最佳吸附率可达93%;(2)流量过大会降低幼虫吸附效果,吸附也更不稳定;(3)幼虫发育先后经历D型幼虫、前期壳顶幼虫、后期壳顶幼虫、踯行期4个时期,吸附材料对后期壳顶和踯行期幼虫的吸附效果较前期壳顶幼虫更好;(4)附着材料密集布置于较短的长度内比稀疏布置于较长的长度内更有利于提高附着效果。     

温度胁迫对茶淡黄刺蛾四种保护酶活力和总抗氧化力的影响

【目的】温度适应性是决定昆虫分布和扩散的重要因素。为探索茶淡黄刺蛾Darna trima(Moore)对温度胁迫的耐受性,本研究测定了温度胁迫对4种抗氧化酶的活力和总抗氧化能力的影响。【方法】分别将茶淡黄刺蛾老熟幼虫置于﹣5、0、5、26(对照)、35、37.5、40℃下处理2、4、6 h,测定其体内超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、谷胱甘肽巯基转移酶(GST)和总抗氧化能力(T-AOC)的活力变化。【结果】茶淡黄刺蛾的4种抗氧化酶的活力和总抗氧化能力在不同温度和时间之间均存在显著变化,但不同指标对温度胁迫具有不同的响应模式。低温胁迫尤其是﹣5℃对各指标影响最为显著,而高温胁迫影响较小。【结论】SOD、CAT、POD、GST和T-AOC在茶淡黄刺蛾应对温度胁迫中具有重要作用,本研究可为判断茶淡黄刺蛾在茶区的分布范围提供一定的理论依据。     

大鼠部分肝切除前后热激处理对过氧化物酶基因表达的影响

用过氧化物酶原位复性电泳(SDS-POD-PAGE)技术分析了部分肝切除(partial hepatectomy,PH)、部分肝切除后再热激(partial hepatectomyfollowing heat shock,PH-HS)和先热激再部分肝切除(heat shock follow ing partial hepatectomy,HS-PH)后肝再生期间过氧化物酶(POD)基因表达差异,结果表明,PH中表达的POD基因种类(7个)>PH-HS(5个)>HS-PH(3个);三个模型的POD总活性为:HS-PH>PH>PH-HS.根据实验结果推测,POD在肝再生和肝损伤恢复中起一定作用。 Abstract:Expression difference of the peroxidase(POD)genes during liver regeneration after partial hepatectomy(PH),partial hepatectomy following heat shock(PH-HS)and heat shock following partial hepatectomy(HS-PH)was analyzed by POD renatured electrophoresis(SDS-POD-PAGE).The results showed that the expressed POD gene kinds in PH,PH-HS and HS-PH were 7,5 and 3 respectively,and that the total activities of POD in the three models were HS-PH>PH>PH-HS.The results suggested that POD play some roles during liver regeneration and in recovery after liver damage.     

大花红山茶花粉形态特征和培养条件及其储藏过程的生理动态分析

以大花红山茶花粉为材料,用扫描电子显微镜观察花粉表观形态,采用离体培养法研究花粉的萌发特性,并就不同贮藏温度与时间对花粉萌发率、超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性的影响进行了分析。结果表明:(1)大花红山茶花粉极面观呈正三角形,沟界极区较宽;花粉粒纹饰为穴状、小沟状雕饰纹;花粉粒平均极轴长为71.05μm;说明大花红山茶在山茶属中具有较为特殊的分类地位和系统进化地位。(2)大花红山茶花粉萌发的最适宜培养基为:150g·L-1蔗糖+20mg·L-1硼酸+100mg·L-1 KNO3+50mg·L-1MgSO4+300mg·L-1 Ca(NO3)2,花粉萌发率可达68.10%。(3)大花红山茶花粉最佳贮藏条件为-80℃;-80℃下贮藏360d后,萌发率仍可达到39.40%。(4)-20℃、-80℃贮藏条件下,大花红山茶花粉3种保护酶(SOD、POD、CAT)的活性较高,花粉抗氧化、抗衰老的能力较强;且在花粉贮藏过程中,3种酶活性高峰值前后花粉萌发率出现大幅度下降。(5)不同贮藏温度下,3种保护酶的作用不同,常温下,SOD为敏感性保护酶;4℃、-20℃下,POD为敏感性保护酶;-80℃下CAT为敏感性保护酶;3种酶活性对花粉萌发率的影响依次为:过氧化氢酶超氧化物歧化酶过氧化物酶。     

多环芳烃荧蒽诱导拟南芥氧化胁迫

选用模式植物拟南芥为材料,以四环的多环芳烃（PAHs）荧蒽为研究对象,从植物对非生物胁迫响应紧密相关的抗氧化酶及膜保护系统的变化入手,研究了植物对多环芳烃胁迫的生理响应.结果表明：荧蒽胁迫下拟南芥经历了氧化胁迫和膜脂过氧化过程.0.75 mmol·L^-1的荧蒽使拟南芥光合作用过程受到抑制;1.00 mmol·L^-1的荧蒽使拟南芥丙二醛(MDA)含量极显著增加, 抗坏血酸过氧化物酶(APX)活性极显著下降, 膜脂过氧化作用加剧,1.25 mmol·L^-1的荧蒽使拟南芥过氧化物酶(POD)活性极显著下降,H₂O₂在细胞内累积,拟南芥明显受害.     

保护酶系在小菜蛾对阿维菌素抗性中的作用

对小菜蛾Plutella xylostella(L.)阿维菌素敏感(ABM-S)和抗性(ABM-R)种群的保护酶系(超氧化物歧化酶SOD、过氧化物酶POD和过氧化氢酶CAT)进行了活性比较。以单头虫表示酶活力,上述3种酶的活性与虫龄正相关,老熟幼虫期酶活性最高。总体上,ABM-S种群的3种酶活性高于ABM-R种群,SOD活性的种群差异随虫龄的增长而减小,1～2龄幼虫ABM-S种群的SOD活性是ABM-R种群的14.27倍。POD活性在3龄幼虫期性差异最大,为4.80倍。CAT活性在4龄末期幼虫无种群差异,其它龄期的活性差异约1～2倍。上述结果表明,阿维菌素抗性并未导致小菜蛾保护酶系统活性增加,这也暗示了昆虫酶系统的能量保守性。     

CO_2浓度升高对粘虫幼虫体内酶活性的影响

【目的】阐明大气CO_2浓度升高对粘虫Mythimna separata(Walker)幼虫不同龄期体内酶活性的影响机制。【方法】测定分析了人工气候箱内不同CO_2浓度(800mL/L和400mL/L)条件下,粘虫幼虫体内4种解毒酶[羧酸酯酶(Car E)、乙酰胆碱酯酶(Ach E)、微粒体多功能氧化酶(MFO)和谷胱甘肽-S-转移酶(GST)]、3种保护酶[超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)]和4种蛋白酶(总蛋白酶、强碱性类胰蛋白酶、弱碱性类胰蛋白酶和类胰凝乳蛋白酶)活性的变化。【结果】(1)粘虫不同龄期幼虫体内4种解毒酶的活力均随着CO_2浓度升高而显著上升(P<0.05);(2)粘虫幼虫体内的保护酶中SOD酶活性在CO_2浓度为800mL/L条件下低于对照(CO_2浓度为400mL/L)条件下的酶活性,其中4至6龄幼虫的下降趋势较为显著(P<0.05),而POD、CAT酶活性均呈上升趋势,800mL/L浓度下的CAT活力均显著高于对照(P<0.05);(3)高CO_2浓度条件下粘虫总蛋白酶的酶活性随着龄期的增加呈现先上升后下降的趋势,强碱/弱碱性类胰蛋白和类胰凝乳蛋白3种酶的比活力均低于400mL/L CO_2浓度下的比活力,其中类胰凝乳蛋白酶比活力显著低于对照条件下的比活力(P<0.05)。【结论】在高CO_2浓度条件下,粘虫幼虫体内的大多数酶系活力呈现下降趋势,大部分解毒酶和蛋白酶活性受到抑制,SOD、CAT和POD 3种保护酶的动态平衡受到干扰而影响其正常的生理代谢,机体受损伤并随龄期的增加而加重。     

小地老虎及粘虫幼虫对灭幼脲表现自然耐药力的体壁结构和生化基础

小地老虎Agrotis ypsilon rottem.幼虫对灭幼脲具有一定的自然耐药力。本文以粘虫Mythimna separata(Walker)作为敏感性虫种与之进行比较,实验结果表明,灭幼脲对两种试虫的室内毒力相差4倍左右,引起差异的原因,在体壁结构方面主要在于:(1)小地老虎幼虫的表皮层较粘虫的厚4.2倍左右;(2)上表皮不是匀质结构,依靠少数蜡道与体表沟通;(3)几丁质片层内的孔道数较少,仅及粘虫的1/4。由此构成了表皮对疏水性的灭幼脲表现抗穿透的性能。小地老虎幼虫体壁还含有较强的生化防卫体系,灭幼脲对多功能氧化酶、芳基酰胺酶有明显激活效应,这两种酶都是灭幼脲的降解酶。由此认为,小地老虎幼虫对灭幼脲所表现的自然耐药力,是由体壁的抗穿透性能以及由灭幼脲所激活的适应酶所造成。     

荞麦种子萌发期多种抗氧化酶活性的研究

通过研究荞麦种子萌发期(0～7 d)超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)和抗坏血酸过氧化物酶(ASP)四种抗氧化酶的酶活性变化,以及对自由基等的清除效果,分析荞麦种子内在抗氧化酶系统在萌发期对细胞膜结构的修复及保护作用。实验结果表明:荞麦种子在萌发期产生的活性氧、自由基等对四种抗氧化酶均有激活效应,其中超氧化物歧化酶(SOD)活性最先上升,其他三种酶随其后被激活,四种酶的氧化反应存在一定关联性和协同作用。苦荞的抗氧化酶活性高于甜荞。     

葡萄糖和维生素C对普安银鲫卵黄囊仔鱼ACC、FAS及CPTⅠ活性的影响

本试验旨在探究普安银鲫(Carassius auratus )卵黄囊仔鱼发育过程中ACC、FAS及CPT I活性变化及葡萄糖和维生素C溶液分别浸泡对它们的影响。采用酶学方法研究了普安银鲫卵黄囊仔鱼过程中ACC、FAS及CPT I活性变化的变化特点。结果显示：在卵黄囊仔鱼发育过程中,对照组与维生素C组中ACC和FAS活性呈上升趋势,CPT I活性呈“下降-上升”变化趋势,而葡萄糖组ACC、FAS及CPT I活性均呈上升趋势,且3种酶的活性均显著高于对照组(P<0.05)。维生素C组ACC活性在内源营养期显著高于对照组,FAS活性在混合营养期和外源营养期显著高于对照组,CPT I活性在内源营养期和外源营养期显著高于对照组(P<0.05)。研究表明：ACC、FAS及CPT I在维持普安银鲫卵黄囊仔鱼发育中脂质代谢的动态平衡起着重要作用,15g/L的葡萄糖溶液可通过调节仔鱼体内脂质代谢酶的活性而形成新的脂质代谢水平,以满足仔鱼生长发育需要;而30mg/L的维生素C对维持仔鱼发育中体内正常的脂质代谢具有重要作用。     

Acid proteinases of the fore-gut in metamorphosing tadpoles of Rana catesbeiana.

1. Two types of acid proteinases were found in the adult stomach of the bullfrog, Rana catesbeiana. 2. The first type of enzyme appeared in the developing stomach and esophagus and contained more than two kinds of acid proteinases. 3. These enzymes were identified as pepsin-type enzymes. 4. The second type of enzyme existed from the larva to adult stage and was also present in the adult duodenum. 5. This enzyme was different from pepsin and thought to be cathepsin E.     

顽拗性三七种子后熟过程超微结构和抗氧化酶变化

该研究以3年生三七成熟种子为材料,通过对三七种子种胚切片观察、抗氧化酶活性测定及相关基因表达量的变化分析,从生理、形态及转录组3个层面了解顽拗性三七种子的内在机理.结果表明:三七种子后熟0~40 d,超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)和谷胱甘肽还原酶(GR)的活性先升高后降低,过氧化物酶(POD)的活性升高.后熟40 d时SOD、POD、CAT、APX相关差异表达基因的FPKM值分别为28、13、356、105,皆处于较高水平,此时观察到完整的细胞结构,种胚完成形态成熟,丙二醛(MDA)含量达到了最高值,说明三七种子内部抗氧化系统抵御氧化伤害最激烈,对水分胁迫造成的氧化伤害最为敏感.伴随后熟时间的延长,膜脂过氧化作用加剧造成细胞膜的降解,导致细胞功能丧失和畸形死亡,抗氧化系统酶活性降低不能有效抵御氧化伤害可能是导致顽拗性三七种子脱水敏感的重要原因之一.     

Various mechanisms of regulation of lipid peroxidation in human erythrocytes after long-term exposure to hyperbaric oxygenation]

Intensity of lipid peroxidation and activity of antioxidant protection enzymes in erythrocytes were measured in three experiments with 10-24 days exposure of aquanauts under 4.6 and 5.1 MPa. It is established that there is no pathological intensification of lipid peroxidation when oxygen partial pressure in breathing gas mixture is optimal. This process is under reliable control by modulation of antioxidant enzymes activity. The high sensitivity of these research methods allows using them to determine exposure limitations under high pressure and optimal oxygen concentrations in breathing gas mixture.     

Chemopreventive efficacy of geraniol against 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch carcinogenesis

The status of lipid peroxidation, antioxidants, and detoxification enzymes were used as biochemical end points to assess the chemopreventive potential of geraniol, a monoterpene, in 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch carcinogenesis. Topical application of 0.5% DMBA in liquid paraffin, three times a week, for 14 weeks developed well-differentiated squamous cell carcinoma in the buccal pouch of golden Syrian hamsters. Although 100% tumor formation was noticed in hamsters treated with DMBA alone, intragastric administration of geraniol, at a dose of 250 mg/kg body weight (b.w.) to DMBA-treated hamster completely prevented the formation of oral tumors. Furthermore, geraniol significantly reduced lipid peroxidation by-products and improved the status of enzymatic and non-enzymatic antioxidants as well as modulated the status of phase I and phase II detoxification enzymes, favoring the excretion of carcinogenic metabolite, during DMBA-induced oral carcinogenesis. The present study concludes that the chemopreventive potential of geraniol relies on its anti-lipid peroxidative and antioxidant function as well as modulatory effects on phase I and II detoxification enzymes to excrete the carcinogenic metabolite, during DMBA-induced hamster buccal pouch carcinogenesis.     

Chemopreventive efficacy of geraniol against 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch carcinogenesis

Abstract

The status of lipid peroxidation, antioxidants, and detoxification enzymes were used as biochemical end points to assess the chemopreventive potential of geraniol, a monoterpene, in 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch carcinogenesis. Topical application of 0.5% DMBA in liquid paraffin, three times a week, for 14 weeks developed well-differentiated squamous cell carcinoma in the buccal pouch of golden Syrian hamsters. Although 100% tumor formation was noticed in hamsters treated with DMBA alone, intragastric administration of geraniol, at a dose of 250 mg/kg body weight (b.w.) to DMBA-treated hamster completely prevented the formation of oral tumors. Furthermore, geraniol significantly reduced lipid peroxidation by-products and improved the status of enzymatic and non-enzymatic antioxidants as well as modulated the status of phase I and phase II detoxification enzymes, favoring the excretion of carcinogenic metabolite, during DMBA-induced oral carcinogenesis. The present study concludes that the chemopreventive potential of geraniol relies on its anti-lipid peroxidative and antioxidant function as well as modulatory effects on phase I and II detoxification enzymes to excrete the carcinogenic metabolite, during DMBA-induced hamster buccal pouch carcinogenesis.     

盐碱协同胁迫对向日葵抗氧化酶系统的影响

根据中国东北盐碱土壤特点,将4种盐NaCl、NaHCO3、Na2SO4和Na2CO3按不同比例混合,模拟出25种盐度和pH值各不相同的复杂盐碱条件(盐浓度为50～250 mmol/L,pH值为712～1046),并对向日葵苗进行盐碱混合胁迫处理,研究了向日葵超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)酶等抗氧化酶系统和丙二醛(MDA)的盐碱协同胁迫效应．结果表明, 向日葵抗氧化物酶活性强弱同时与盐度和碱度密切相关,3种抗氧化物酶活性对于盐浓度的反应相似,均为其含量随着盐浓度的升高开始逐渐升高然后下降,而对于pH的影响,不同酶反应结果不同．即随着pH值升高,SOD酶活性和CAT酶活性降低,而POD酶活性反应则是随着pH值升高活性也升高．双向方差分析(ANOVA)结果表明：盐碱效应对于3种酶活力的影响是显著的．其中,盐效应对POD和SOD活性的影响比pH值的影响大,而pH值对CAT活性的影响效应比盐效应大．除SOD外,盐碱效应的交互作用显著 (P<0001)．抗氧化酶系统和MDA含量两者间相关性和逐步回归分析表明,3种酶对MDA的影响效应随其强度不同呈现显著不同．其中SOD是1个主导因子,CAT 处于次位, 而POD的影响不大,甚至可以忽略．     

Response of hydroperoxidase and superoxide dismutase deficient mutants of Escherichia coli K-12 to oxidative stress

In Escherichia coli, the coordinate action of two antioxidant enzymes, superoxide dismutase and hydroperoxidase (catalase), protect the cell from the deleterious effects of oxyradicals generated during normal aerobic respiration. To evaluate the relative importance of these two classes of enzymes, strains of E. coli deficient in superoxide dismutase and (or) hydroperoxidase were constructed by generalized transduction and their physiological responses to oxygen and oxidant stress examined. Superoxide dismutase was found to be more important than hydroperoxidase in preventing oxygen-dependent growth inhibition and mutagenesis, and in reducing sensitivity to redox-active compounds known to generate the superoxide anion. However, both types of enzymes were required for an effective defense against chemical oxidants that generate superoxide radicals and hydrogen peroxide.