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1.
研究了氮离子注入对耐辐射异常球菌(Deinococcusradiodurans)细胞内超氧化物歧化酶(SOD)活性的影响及其对MnSOD的诱导。结果表明,当20keV氮离子的注入剂量低于8×1014ions/cm2时,D.Radiodurans中SOD活性变化不大,当剂量在8×1014~60×1014ions/cm2范围内时,SOD的活性随着注入剂量的增大逐渐提高,但大于60×1014ions/cm2时,则逐渐下降;加入对不同金属辅基的SOD同工酶活性抑制剂H2O2和氯仿乙醇的研究表明,中高剂量下氮离子注入诱导的是D.Radiodurans中MnSOD活性的提高,在正常生理条件及小于8×1014ions/cm2的剂量下,D.Radiodurans中SOD总活性主要由FeSOD构成  相似文献   

2.
以E.coli和耐辐射微球菌(Deinococcusradiodurans)为试材,研究了N+离子注入对其SOD、CAT和POD活性的影响及其对自由基的清除。结果表明:D.radiodurans经N+离子注入后SOD和CAT酶活高于E.coli的,而POD酶活不仅很低也低于E.coli的;随剂量的增大,两者SOD和CAT酶活均为先增后减,只是其SOD酶活的变化峰值对应剂量分别为6×1015N+/cm2和2×1015N+/cm2,而CAT的则均为4×1015N+/cm2;它们的POD酶活变化则不同,各处理耐辐射微球菌POD酶活保持低而恒定的水平,而大肠杆菌的则是中低剂量较恒定,较高剂量逐渐增大;对1016N+/cm2注入的细胞培养到后对数期,再测其自由基ESR波谱信号强度,发现比同剂量注入、未进行培养的要弱的多。  相似文献   

3.
以E.coli和耐辐射生球菌(Deinococcusradiodurans)为试材,研究了N^+离子注入对其SOD,CAT和POD活性的影响及共对自由基的清除,结果表明:D.radiodurans经N^+离子注入后SOD和CAT酶活高于E.coli的,而POD酶活不仅很低于E.coli的;随剂量的增大,两者SOD和CAT酶活均为增后减,只是其SOD酶活的变化峰值对应剂量分别为6×10^15N^+/  相似文献   

4.
普通水绵〔Spirogyracommunis(Hassal)Kützing〕的超氧物歧化酶(SOD)含有2条锰型和1条铁型同工酶主带。低浓度的Zarouk培养液对SOD影响不明显,浓度提高到3倍以上时造成渗透胁迫,在一定时间内,SOD比活升高,但培养时间继续延长则下降。在百草枯1mmol/L和2mmol/L培养6d和4d时,普通水绵SOD比活最高,此后则下降;2mmol/L组的MDA含量在试验期内一直缓缓上升。5倍的Zarouk培养液和2mmol/L百草枯进行培养后,FeSOD带消失,MnSOD主活性带有增强的趋势。  相似文献   

5.
用PAGEA活性染色分析了D.radiodurans过氧化氢酶(Cat)和起氧化物歧化酶(SOD)。2种同种异型D.radiodurans(R1和Sark)的Cat在电泳带型上存在差异,两者Kat均可分为A、B和C3条带,但各带所占比例明显不同,SOD的分析结果表明,D.radiodurans SOD以Fe^2+和Mn^2+离子的嵌合体形式存在,其中Fe-SOD成分占90%以上。PAGE活性染色法  相似文献   

6.
6BA诱导的带正电荷的葡萄叶过氧化物酶   总被引:1,自引:0,他引:1  
河岸葡萄叶的带正电荷过氧化物酶(cationic peroxidase, CPOD) 可受6BA 诱导,但盐、H2O2 或Fe2++ H2O2 均使叶片CPOD 活性明显下降,而高浓度的无机盐明显刺激纯CPOD 活性增加。在以愈创木酚为底物时CPOD 最适pH 为4 .60 ~5 .75 ,对H2O2 的表观Vmax 和Km 值分别为110 U/mg 蛋白和1 .15m mol/L。  相似文献   

7.
MPEG-SOD对急性低氧下鼠左心功能的保护作用   总被引:1,自引:0,他引:1  
单甲氧基聚乙二醇(MPEG)活化后与超氧化物歧化酶(SOD)偶联,经纯化后得到MPEG-SOD,鉴定其分子量约为7.0×105Dation。其在血液循环中酶活性半衰期超过30h,远大于天然SOD(6-10min)。SD雄性大鼠分三组.对照组(n=8.由股静脉注入0.2ml生理盐水)、NativeSOD组(n=8,注以0.2ml生理盐水配的800USOD)和MPEG-SOD组(n=9,注以800UMPEG-SOD)。低氧前三组鼠的心率(HR)、左室内峰压(LVP)、左室压微分(LV±dp/dtmax)和股动脉压(AP)均无统计学差别。在模拟6000—6500m高度急性低氧1.8.14min记录上述各项指标,结果如下:除HR外,NativeSOD组与对照组各指标均无统计学差别,MPEG-SOD组的各项指标均明显高于对照组。表明MPEG-SOD对急性低氧导致的左心室力学指标的减弱有明显保护作用,提示超氧自由基(O2-)在急性低氧导致左心室功能损伤中起重要作用,即可能是由O2-及其衍生的其它自由基损害心肌细胞生物膜系统所致。  相似文献   

8.
首次采用烟草愈伤组织,经不同剂量的N+离子束注入处理,与对照组(非注入非真空组、真空处理组)比较分析结果表明:超氧自由基(O.-2)产生速率升高、过氧化氢(H2O2)和丙二醛(MDA)含量增加。在低剂量(13×1015N+/cm2)注入时,超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)的活性升高;随着剂量加大(≥4×1015N+/cm2),它们的活性反而降低。同时N+离子束注入有直接钝化酶的效应,从而导致离子束注入组的酶活性比对照组酶活性低,对过氧化物酶尤其如此。  相似文献   

9.
青海南部七种翠雀属植物的核型   总被引:1,自引:1,他引:0  
报道了采自青海南部7 种翠雀属( Delphinium L.) 植物的染色体数目和核型。大通翠雀花D.pylzowii 的核型公式为2n= 16 = 2m + 4sm + 10st; 毛翠雀花D. trichophorum 的核型公式为2n= 16 = 2m + 4sm + 10st; 蓝白翠雀花D.albocoerulum 的核型公式为2n = 16 = 2m + 4sm(2SAT) + 10st; 囊谦翠雀花D. nangchienense 的核型公式为2n = 16 = 2m + 6sm + 8st; 唐古拉翠雀花 D.tangkulaense 的核型公式为2n = 16 = 2m (2SAT) + 6sm + 8st; 单花翠雀花 D.candelabrum var. monanthum 的核型公式为2n = 16 = 2m + 6sm + 8st; 展毛翠雀花D. kamaoensevar. glabrescens 的核型公式为2n = 16 = 2m + 6sm + 8st; 前5 种植物的染色体数目与核型为首次报道。  相似文献   

10.
Ms—SOD对CHO细胞电离辐射敏感性的影响   总被引:7,自引:1,他引:6  
近年来的研究发现,IL-1和TNF最重要的辐射防护因子,因IL-01和TNF都能造反性诱导Mn-SOD的高度表达,因此认为Mn-SOD可能有辐射防护作用。通过转染有义和反义Mn-SODcNDA小于CHO细胞,进一步说明了Mn-SOD在抗电离辐射损伤中的作用。  相似文献   

11.
以低能氮离子束为诱变源,对甘草种进行注入处理后,以萌发的幼苗为材料对其在干旱胁迫条件下保护酶活性及MDA含量变化进行研究.结果表明注入后甘草种的存活率呈现马鞍形曲线变化,其中在4.1×1016N+/cm2剂量处达到鞍点,在剂量4.6×1016N+/cm2处存活率高于对照.在干旱胁迫下,随着胁迫时间的延长,离子束注入后萌发的幼苗MDA含量明显低于对照.酶活结果显示,在干旱胁迫后期,剂量4.6×1016N+/cm2处理后的甘草幼苗SOD和CAT酶活性都高于对照,说明该注入剂量处理甘草种有助于提高甘草幼苗的抗旱性能,SOD同工酶结果也证明该剂量的离子注入对干旱胁迫下同工酶谱带有所影响.  相似文献   

12.
以2份水稻二倍体及其相应的同源四倍体为试验材料,采用3种不同剂量的低能N+离子束对其种胚进行注入处理,对其出芽率、成苗率以及幼苗期5种主要生理指标:超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、丙二醛(MDA)和可溶性糖进行初步测定。结果表明:随着辐射剂量的增加,试验材料的出芽率和成苗率均呈下降趋势,在最高剂量处理条件下(5.0×1017N+/cm2)试验材料的出芽率、成苗率与对照相比差异达极显著水平(P<0.01)。二倍体材料幼苗SOD、POD、CAT的活性均呈先上升后下降的趋势,并在3.0×1017N+/cm2的剂量下达到最高,而四倍体材料幼苗SOD、POD、CAT的活性则呈先上升后下降再上升的趋势,并在1.0×1017N+/cm2的剂量下达到最高。二倍体材料幼苗MDA含量的变化呈先下降再上升的趋势;四倍体材料幼苗MDA含量的变化呈先下降后上升再下降的趋势。两种染色体组倍性水稻材料中可溶性糖含量在各处理组间差异不是特别显著,但均低于空白对照组。由此可见,不同剂量的低能N+离子束会对试验材料的出芽率、成苗率以及幼苗期的主要生理特性产生显著的影响,且不同染色体组倍性材料间也存在一定的差异。  相似文献   

13.
Dynamic light scattering measurements were performed on spectrin from human erythrocytes in 25 mM Tris buffer at pH 7.6 with 100 mM NaCl and 5 mM EDTA. Measurements were made on spectrin solutions prepared as dimers and tetramers over the temperature range from 23 to 41 degrees C, as a function of the square of the scattering vector (K2) over the range of 0.7 x 10(10) cm-2 less than or equal to K1 less than or equal to 20 x 10(10) cm-2. Analysis of the autocorrelation functions collected for these solutions revealed the presence of two predominant motional components over the entire range of K2. Plots of the diffusion coefficients (D20) of these components, with viscosity and temperature corrected to water at 20 degrees C, as a function of K2 indicated three rather distinct regions, flat regions at low and high K2 joined by a sloping intermediate region. At small K2 (less than or equal to 4 x 10(10) cm-2) the D20 values were (7.3 +/- 2.0) x 10(-8) cm2/s for the slow component and (20.3 +/- 2.0) x 10(-8) cm2/s for the fast component. At large K2 (greater than or equal to 10 x 10(10) cm-2) the values increased to (13.0 +/- 2.0) x 10(-8) cm2/s for the slow component and (39.4 +/- 2.0) x 10(-8) cm2/s for the fast component. In the intermediate K2 region, D20 is a linear function of K2 and appears as a transition between the low and high K2 regions.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

14.
The nitric oxide synthase inhibitor N(G)-nitro-L-arginine methyl ester (l-NAME) increased vascular resistance (VR) 10% above baseline of 3.08+/-0.08 (n=11) mmHg/mL/min at 10 mg/kg and 20% above 3.05+/-0.08 (n=9) at 50 mg/kg in anesthetized toads (Bufo marinus). Blood pressure was unaffected by either dose of L-NAME. Blood flow decreased at the higher dose of L-NAME. L-arginine (300 mg/kg) reversed the effects of L-NAME on VR and blood flow in toads treated with 10 mg/kg but not with 50 mg/kg. Injection of 50 mg/kg L-NAME into empty-bladder toads produced a 10% decrease in water uptake, J(v), resulting in a J(v) of 1,267+/-11 cm(3)/cm(2)/s x 10(-7) (n=9) compared to 1,385+/-12 (n=8) for controls. Injection of 10 microg/kg angiotensin II (ANG II) increased J(v) 15% across the pelvic patch (J(v), cm(3)/cm(2)/s x 10(-7)), resulting in a J(v) of 1,723+/-12 cm(3)/cm(2)/s x 10(-7) (n=8) compared to 1,471+/-12 (n=8) for controls. It is hypothesized that during cutaneous drinking blood flow into the capillary bed of the pelvic patch is regulated by nitric oxide and ANG II.  相似文献   

15.
N+离子注入对大豆种子活力及其幼苗的抗氧化酶活性影响   总被引:8,自引:0,他引:8  
本文研究了用25keV N+注入丰豆103的种子后,N+离子对其种子的活力及子叶伸展后48小时和96小时的幼苗内蛋白质含量、谷胱甘肽巯基转移酶(GSH-Ts)、谷胱甘肽过氧化酶(GSH-Px)、抗坏血酸过氧化物酶(ASA-POD)活性的影响.结果表明当N+注量在2.6×1016N+/cm2~5.2×1016N+/cm2时,种子的发芽率、发芽指数、活力指数都明显提高;幼苗的可溶性蛋白含量高于对照.在6.5×1016N+/cm2~10.4×1016N+/cm2注量时,幼苗的可溶性蛋白含量低于对照,96小时幼苗可溶性蛋白的含量高于48小时,说明辐射引起的损伤可随生长时间的增加而有所恢复.高注量可引起幼苗内一些抗氧化酶活性的升高,且随注量的增加酶的活性升高也越明显,96小时幼苗的GSH-Px和ASA-POD活性高于48小时幼苗,GSH-Ts活性略有下降.而低注量(1.3×1016N+/cm2~5.2×1016N+/cm2)的上述酶指标升幅不大.说明经N+离子处理后可通过诱导这些抗氧化酶活性的升高起到减轻伤害的作用.  相似文献   

16.
蚕豆叶片SOD活性监测大气SO2污染的可行性研究   总被引:12,自引:0,他引:12       下载免费PDF全文
 本文从实验室熏气和野外大气暴露两方面对利用蚕豆叶片SOD活性评价和监测大气SO2污染的可行性进行了研究。低浓度SO2(0.1312、0.2601mg·m-3)处理,引起叶片SOD活性升高,一定时间后,SOD活性趋于稳定,且0.2601mg·m-3SO2处理时,SOD活性较高,表现出SOD活性增量与SO2浓度相关,为利用SOD活性监测和评价SO2污染提供了可能性。大气暴露试验结果表明SOD活性与大气硫酸盐化速率存在极显著的相关性。利用SOD活性和大气硫酸盐化速率分别对大气SO2污染程度进行了评价,结果基本一致,并根据SOD活性估测了大气硫酸盐化速率,符合程度较高,置信分析表明估测结果可信。以上结果表明,利用蚕豆叶片SOD活性监测和评价大气SO2污染是可行的。  相似文献   

17.
Noradrenaline modulates the immunity of white shrimp Litopenaeus vannamei   总被引:1,自引:0,他引:1  
The total haemocyte count (THC), phenoloxidase activity, respiratory burst, superoxide dismutase (SOD) activity, phagocytic activity and clearance efficiency in response to pathogen Vibrio alginolyticus were measured when the white shrimp Litopenaeus vannamei (18.4 +/- 1.2 g) were injected individually with noradrenaline at 10(-8), 10(-7) and 10(-6) mol shrimp(-1). For the shrimp that received noradrenaline at 10(-8), 10(-7) and 10(-6) mol shrimp(-1), the THC decreased by 15%, 21% and 32%, phenoloxidase activity decreased by 15%, 31% and 31%, respiratory burst decreased by 13%, 21% and 32%, and SOD activity decreased by 46%, 56% and 55%, respectively, after 2 h. The phagocytic activity and clearance efficiency of shrimp that received noradrenaline at either dose decreased significantly after 2 h. The THC, phenoloxidase activity, respiratory burst, SOD activity, phagocytic activity and clearance efficiency returned to normal values after 4, 4, 8, 24, 16 and 8 h, respectively, in the shrimp that received noradrenaline at either dose. In another experiment, L. vannamei which had received noradrenaline at 10(-8), 10(-7) and 10(-6) mol shrimp(-1) were challenged after 1h by injection with V. alginolyticus at 1.0 x 10(5) colony-forming units (cfu)shrimp(-1) and then placed in seawater of 20 per thousand. The cumulative mortality of shrimp that received noradrenaline at either dose was significantly higher than that of shrimp that received saline after 4 h, and at the termination of the experiment (48 h after the challenge). It is therefore concluded that noradrenaline administration at 10(-6) mol shrimp(-1) or less causes immune modulation of L. vannamei.  相似文献   

18.
本文对离子束技术的注入工艺和在不同能量下的不同注入剂量下黑曲霉的存活率和突变率进行了研究,目的是为了找到恰当的注入工艺和良好的注入参数,使诱变达到较好的效果。结果发现:当注入离子为氮离子时,在10keV的能量下注入剂量为5.2×1014ions/cm2和1.56×1015ions/cm2时,诱变效果较好。在这注入条件下,通过培养基优化,使木聚糖酶酶活达到600IU/ml。  相似文献   

19.
Effects of dopamine on the immunity of white shrimp Litopenaeus vannamei   总被引:5,自引:0,他引:5  
The total haemocyte count (THC), phenoloxidase activity, respiratory burst, superoxide dismutase (SOD) activity, phagocytic activity and clearance efficiency in response to pathogen Vibrio alginolyticus were measured when the white shrimp Litopenaeus vannamei (20.0+/-1.5 g) were injected individually with dopamine at 10(-8), 10(-7) and 10(-6)mol shrimp(-1), respectively. For the shrimp that received dopamine at 10(-7) and 10(-6)mol shrimp(-1), the THC decreased by 25% and 39%, phenoloxidase activity decreased by 15% and 32%, respiratory burst decreased by 21% and 36%, and SOD activity decreased by 50% and 63%, respectively, after 4 h. The phagocytic activity and clearance efficiency of shrimp that received dopamine at either dose decreased significantly after 2 h. The THC, phenoloxidase activity, respiratory burst, SOD activity, phagocytic activity and clearance efficiency returned to normal values after 16, 8, 8, 24, 16 and 4 h, respectively, for the shrimp that received dopamine at either dose. In another experiment, L. vannamei which had received dopamine at 10(-8), 10(-7) and 10(-6)mol shrimp(-1) were challenged after 1 h by injection with V. alginolyticus at 1.0x10(5) colony-forming units (cfu) shrimp-1 and then placed in seawater of 20 per thousand. The cumulative mortality of shrimp that received dopamine at either dose was significantly higher than that of shrimp that received saline after 8 h, and of shrimp that received saline at the termination of the experiment (48 h after the challenge). It is therefore concluded that dopamine administration at 10(-6)mol shrimp-1 or less causes immune modulation of L. vannamei.  相似文献   

20.
Deinococcus radiodurans is a potent radiation resistant bacterium with immense potential in nuclear waste treatment. In this investigation, the translational and rotational dynamics of dilute suspensions of D. radiodurans cultured under controlled growth conditions was studied by the polarized and depolarized dynamic light-scattering (DLS) techniques. Additionally, confocal laser scanning microscopy was used for characterizing the cultured samples and also for identification of D. radiodurans dimer, tetramer, and multimer morphologies. The data obtained showed translational diffusion coefficients (DT) of 1.2 x 10(-9), 1.97 x 10(-9), and 2.12 x 10(-9) cm2 /s, corresponding to an average size of 3.61, 2.22, and 2.06 microm, respectively, for live multimer, tetramer, and dimer forms of D. radiodurans. Depolarized DLS experiments showed very slow rotational diffusion coefficients (DR) of 0.182/s for dimer and 0.098/s for tetramer morphologies. No measurable rotational diffusion was observed for multimer form. Polarized DLS measurements on live D. radiodurans confirmed that the bacterium is nonmotile in nature. The dynamics of the dead dimer and tetramer D. radiodurans were also studied using polarized and depolarized DLS experiments and compared with the dynamics of live species. The dead cells were slightly smaller in size when compared to the live cells. However, no additional information could be obtained for dead cells from the polarized and depolarized dynamic light-scattering studies.  相似文献   

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