Effects of freeze and cold stress on certain physiological and biochemical traits in sensitive and tolerant barley (Hordeum vulgare) genotypes

An experiment was performed as a split-plot design based on a randomized complete block (RCB) with three replicates. The aim was to explore physiological traits, catalase (CAT) and peroxidase (POD) activity associated with cold and freeze stress in four barley genotypes (two stress-tolerant genotypes and two sensitive genotypes). The genotypes were regarded as sub-plots and five temperature levels (namely 20, 4, 0, ?4, ?8°C) as main plots. The results revealed that the hydrogen peroxide (H₂O₂) and malondialdehyde (MDA) content increased through freeze and cold stress from 20 to 4°C. This increase was more in the sensitive genotypes than in the tolerant ones. Subsequent to the increase in lipid peroxidation, the membrane stability index (MSI) decreased, thereby increasing the electrolyte leakage. The sensitive genotypes demonstrated greater reduction in the studied parameters. Upon the increase in the H₂O₂ content, the antioxidant enzymes CAT and POD also increased in order to collect and prevent H₂O₂ from damaging the cell and the plant. Compared with the sensitive ones, the tolerant genotypes indicated more increase in the enzymes. The H₂O₂ and MDA content decreased from ?4 to ?8°C, which could be due to intracellular freezing in the sensitive genotypes, but due to the detoxifying of the antioxidant enzymes in the tolerant genotypes. Compared with the POD content, the increase in the CAT content through cold stress was more, which could mean that it was possibly CAT which acted as the main inhibitor of H₂O₂ in cold stress in the barley plant.     

基于光谱稳定目标的经验线性大气校正方法研究

By using speetrally stable targets, the empirical line （EL） method was tested to correct the multispectral IKONOS imagery acquired over Putuo Mountain, Zhejiang, China. A series of calibration targets, which were spectrally stable over time, were selected to establish the linear predicted equation. Subsequently, a series of spectrally stable validation targets were selected to assess the accuracy of the equations. And, validation targets, which were speetrally unstable over time, were used to test the feasibility of using the EL method to calibrate the archival remotely sensed data. Ground reflectance measurements for each target were made using an ASD FieldSpec spectroradiometer. A Trimble GeoXTTM GPS unit with sub-meter accuracy was used to estimate the target position accurately. Linear regression equations for four tKONOS bands were derived. The coefficients of determination for the blue, green, and red bands were all greater than 0.9800 and it was 0.9697 for the near infrared band. It was concluded that reasonable results could be obtained by using speetrally stable targets.     

Enhanced Lipid Peroxide Levels in the Erythrocytes of Calves with Haemoglobinuria

Eight 6–9 month old calves, showing clinical signs of intermittent haemoglobinuria, even after treatment with an antipiroplasmal drug (4,4-diamidinodiazoaminobenzene diaceturate), were examined for oxidative damage to their erythrocytes and the presence of hemoprotozoa in blood smears. Four calves without signs of haemoglobinuria served as controls. The blood smears from three of the eight calves contained piroplasms for Theileria annulata. Irrespective of the presence of piroplasms in their blood smears, the calves with haemoglobinuria had significantly (p<0.01) lower haemoglobin concentrations (Hb) and packed cell volumes (PCV). The lipid peroxide level in the erythrocytes, but not in the plasma, of calves with red urine was significantly (p<0.05) higher than that for the controls. It is concluded that haemoglobinuria, irrespective of the presence of piroplasms in blood smears, is associated with oxidative stress to erythrocytes and peroxidation of polyunsaturated fatty acids of cell membrane.     

3种中药有效成分对小鼠胚胎体外发育的影响

以mCZB添加抗生素为对照组,以分别添加0.1 mg/L小檗碱(berberine,BR)、0.5 mg/L川芎嗪(ligustrazine,Lig)和4 mg/L黄芩苷(baicalin,Bai)为试验组,比较各组胚胎孵化率、微滴中一氧化氮(Nitric oxide,NO)和丙二醛(malondialdehyde,MDA)含量及孵化胚胎的细胞数量,从而探讨中药有效成分对小鼠早期胚胎体外发育的影响。结果显示,Bai组(80.2%,81.3%)、Lig组(78.9%,77.6%)及BR组(76.7%,71.6%)胚胎孵化率极显著高于对照组(50.7%、47.8%)(P<0.01)。各组间NO含量,72 h较24 h均有减少,而120 h又均有增加且最高。各组间MDA含量,72 h和120 h与24 h比较呈现增加趋势,除Bai组120 h外,对照组均高于试验组。孵化胚胎细胞计数结果显示,BR组(87.2±8.6)、Lig组(83.9±7.7)和Bai组(81.9±6.2)与对照组(77.4±5.6)差异极显著(P<0.01)。结果表明:3种中药有效成分均能促进小鼠早期胚胎的体外发育及胚胎细胞增殖,并对NO和MDA含量有一定影响。     

低温胁迫对喜树幼苗SOD活性、MDA和脯氨酸含量的影响

本文对低温胁迫下喜树幼苗叶片内超氧化物歧化酶（SOD）活性与叶绿素、游离脯氨酸、丙二醛（MDA）含量的变化进行了研究。结果表明：喜树幼苗经低温胁迫后叶内叶绿素含量下降；SOD活性先下降、后上升、再下降，其变化规律不同于其它植物；低温造成喜树幼苗的膜脂过氧化，MDA含量明显升高，SOD活性的增强可以降低MDA的含量；脯氨酸随着胁迫的进行其含量升高，表明叶内脯氨酸的升高也有助于提高它的抗寒性，进一步可以认为叶片内脯氨酸含量的高低可作为衡量喜树抗寒性指标。     

Serum markers of lipid peroxidation, antioxidant enzymatic defense, and collagen degradation in an experimental (Pond-Nuki) canine model of osteoarthritis

BACKGROUND:Chondrocyte lipid peroxidation is strongly suggested to mediate collagen degradation and thus, to be involved in the pathogenesis of cartilage degradation and osteoarthritis (OA). OBJECTIVES: The objective of this study was to evaluate early changes in serum biochemical indicators of oxidative stress during the development of OA in a canine model. METHODS: Experimental OA was induced in 7 dogs by transection of the anterior cruciate ligament (Pond-Nuki model). Venous blood samples were obtained prior to the operation and on postoperative days 30, 60, and 105. The activity of serum catalase (an antioxidant enzyme), malondialdehyde (MDA) concentration (a marker of lipid peroxidation), and serum C2C neoepitope concentration (a marker of collagen type II degradation) were measured. RESULTS: A statistically significant increase in all parameters as early as the 30th postoperative day was observed, compared with preoperative values. Serum catalase activity peaked on day 60, whereas MDA and C2C concentrations increased continuously until the end of the experimental period. A significant positive correlation was found between MDA and C2C concentrations, but not between catalase activity and MDA or C2C concentrations. CONCLUSIONS: The results support the hypothesis that oxidative stress is involved in the pathogenesis of OA in the dog based on the Pond-Nuki model. The correlation between MDA and C2C concentrations suggests a possible association between oxidative stress and cartilage degeneration.     

不同耐盐性燕麦对盐胁迫的生理响应

为研究不同耐盐性燕麦(Avena sativa)对盐胁迫的生理响应,以青永久195 (耐盐材料)和709 (盐敏感材料)为试验材料,采用营养液沙培法,对3周龄燕麦幼苗进行150 mmol·L?1 NaCl处理0 (CK)、6、24、72 h,探讨了盐胁迫对两种燕麦幼苗光合作用、抗氧化特性、渗透调节物质含量的影响。结果表明：随着处理时间的延长,燕麦幼苗叶片的叶绿素含量、净光合速率(net photosynthetic rate, Pn)、蒸腾速率(transpiration rate, Tr)、气孔导度(stomatal conductance, Gs)、胞间二氧化碳浓度(intercellular carbon dioxide concentration, Ci)、K+含量均有所下降;过氧化物酶(peroxidase, POD)、超氧化物歧化酶(superoxide dismutase, SOD)活性、脯氨酸和可溶性糖含量呈先升高后降低的趋势,过氧化氢酶(catalase, CAT)活性、丙二醛(malondialdehyde, MDA)和Na+含量均有所增加。其中在盐胁迫下耐盐材料青永久195叶片的叶绿素含量、Pn、Tr和Gs下降幅度小于盐敏感材料709;SOD、CAT、脯氨酸含量和可溶性糖含量均高于709,MDA含量低于709。盐胁迫6、24 h时,青永久195根中K+、Na+含量低于709,72 h时高于709;盐胁迫6和24 h时,青永久195叶中K+含量高于709,Na+含量低于709。综上,耐盐材料青永久195表现出较好的渗透调节能力,维持较高的抗氧化酶活性和生物膜稳定性。     

不同蛋白源饲料中添加α-酮戊二酸对松浦镜鲤抗氧化能力的影响

在水温为23℃的控温水循环系统中,采用2×2双因素方法,研究在豆粕蛋白源和鱼粉与豆粕复合蛋白源饲料(蛋白质水平为28%)中分别添加0和1.5%α-酮戊二酸(AKG)对初始体质量为(217.93±0.78)g的松浦镜鲤Cyprinus carpio Songpu抗氧化能力的影响,每组设5个重复。10周饲养结果表明:在不同蛋白源饲料中添加1.5%AKG显著提高了松浦镜鲤肠道和血清中还原型谷胱甘肽(GSH)含量以及超氧化物歧化酶(SOD)活性(P0.05),显著降低肠道和血清丙二醛(MDA)含量(P0.05);豆粕蛋白源中添加AKG显著提高肝脏GSH含量(P0.05);饲料中添加1.5%的AKG对肝胰脏中其他抗氧化指标和肌肉抗氧化指标无显著影响(P0.05)。蛋白源和AKG水平对血清SOD活性具有显著交互作用(P0.05)。综上所述,饲料中添加1.5%AKG可以提高松浦镜鲤的抗氧化能力。     

铜锌元素与仁用杏丙二醛含量关系的研究

针对北方冬季仁用杏花芽、枝条受冻,早春易受晚霜危害出现冻花、冻果的现象,通过测定四种处理下仁用杏各部位的铜、锌含量和各部位的丙二醛含量,找寻二者间关系,探讨铜锌对仁用杏抗逆性的影响。结果表明：铜、锌不同处理下仁用杏丙二醛含量差异极显著,各处理丙二醛含量由低到高依次排序为Cu（0）Zn（3）〈Cu（3）Zn（3）〈Cu（3）Zn（0）〈Cu（0）Zn（0）;铜、锌处理的丙二醛含量均低于对照;Cu^2＋和Zn^2＋可抑制仁用杏苗木细胞膜的脂质过氧化作用,降低细胞膜受损程度,提高仁用杏抗逆性;铜、锌提高仁用杏抗逆性反映在SOD活性变化上,铜、锌通过增强SOD活性,降低超氧自由基含量,而抑制细胞膜脂质过氧化作用,进而提高仁用杏抗逆性。     

臭氧对条石鲷幼鱼鳃组织结构和抗氧化系统的影响

臭氧(O₃)在工厂化养殖水处理中有较高的应用价值,为了解臭氧对条石鲷幼鱼的影响,采用自制的臭氧毒性试验装置(授权利号:ZL 200920122441.3),对条石鲷幼鱼进行了不同质量浓度(0、0.08、0.13、0.17、0.22、0.28和0.32 mg/L)和不同时间(0.5、1、6、12、18和24 h)的急性胁迫试验,并分析了臭氧对条石鲷幼鱼的行为响应、半致死浓度、幼鱼鳃的组织形态学、酶活性等的影响。结果表明,随着臭氧胁迫浓度的升高,条石鲷幼鱼在水层中的分布位置逐渐上移,呼吸频率逐渐加快,受惊反应逐渐迟缓;条石鲷幼鱼的开始死亡时间与臭氧浓度负相关,12 h的半致死方程为Y=16.815 8+20.340 5X(r=0.998 7),半致死浓度为0.262 5 mg/L。24 h的半致死方程为Y=17.614 1+17.898 3X(r=0.950 0),半致死浓度为0.197 4 mg/L;条石鲷幼鱼鳃SOD和GPX活性与臭氧胁迫时间和胁迫浓度负相关,并都在胁迫24 h、质量浓度0.32 mg/L时降至谷值;MDA含量与臭氧胁迫时间和胁迫浓度正相关,并在胁迫24 h、质量浓度0.32 mg/L时达到峰值;在臭氧胁迫下,条石鲷幼鱼的鳃小片细胞排列不规则并萎缩,鳃小片上皮细胞脱落或粘滞于鳃小片间,鳃小片末端膨大,鳃丝血管固缩无腔或变空腔,管壁粗糙、干缩,血细胞固缩、坏死,零散分布或紧贴血管壁。