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1.
Fractionation by chromatography on Sephadex G-200 of a saline extract of Cysticercus cellulosae scolex antigen yielded three distinct fractions associated with distinct peaks. These fractions were analysed by double immunodiffusion (DID) and immunoelectrophoresis (IEP). The three peaks gave five, four and three antigenic determinants, respectively, by DID with homologous hyperimmune rabbit serum. However, the same serum gave nine antigenic determinants of scolex antigen by DID and 11 components by IEP. The IEP demonstrated seven and five antigenic components in the first two peaks. The first peak gave a stronger reaction in indirect haemagglutination than the others. There were common antigenic components in C cellulosae and C tenuicollis antigens.  相似文献   

2.
为探讨不同浓度的绿萝花制剂对线粒体的抗氧化作用及毒理作用,以小鼠胚胎成纤维细胞及其线粒体为研究对象,在最大无毒作用浓度(TC_0)的基础上设计3个浓度药物组,在TC_0下设计6个浓度药物组,以成纤维细胞线粒体膜电位(MMP)和线粒体总活性氧含量(ROS)为检测指标,在4个不同作用时间点,研究绿萝花对成纤维细胞线粒体的影响。结果表明,绿萝花制剂对鼠胚成纤维细胞(MEF)的TC_0为0.25g/mL,但ROS已急剧上升,MMP下降;绿萝花浓度为0.03g/mL时,抗氧化能力最强,随着浓度的上升(0.03g/mL~0.25g/mL),线粒体抗氧化能力减弱或消失;随着给药浓度的升高,细胞凋亡现象出现趋势明显,浓度高于TC_0时,表现出毒性作用,浓度升高,毒性增大。绿萝花干膏制剂0.03g/mL(以生药含量计算)具有抵抗由H_2O_2引起的MEF线粒体MMP下降和ROS的升高的功能,表现出一定的抗氧化能力和阻滞细胞凋亡发生的作用;TC_0及之上浓度具有细胞毒性作用。  相似文献   

3.
The objective of the study was to evaluate the protective effect of Calendula officinalis propylene glycol extracts against oxidative DNA damage and lipid peroxidation induced by high polyunsaturated fatty acid (PUFA) intake in young growing pigs. Forty young growing pigs were assigned to five treatment groups: control; oil (linseed oil supplementation); C. officinalis 1 and 2 groups (linseed oil plus 3 ml/day of C. officinalis propylene glycol extracts); and vitamin E group (linseed oil plus 100 mg/kg of vitamin E). Lymphocyte DNA fragmentation and 24-h urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) excretion were measured to determine DNA damage. Lipid peroxidation was studied by analysing plasma and urine malondialdehyde (MDA), and urine isoprostane concentrations (iPF2α-VI), total antioxidant status of plasma and glutathione peroxidase (GPx) assays. C. officinalis 1 (extract from petals) effectively protected DNA from oxidative damage. It indicated a numerical trend towards the reduction of plasma MDA and urinary iPF2α-VI excretion. Its effect was comparable with that of vitamin E. C. officinalis 2 (extract from flower tops) showed less antioxidant potential than the extract from petals. We can conclude that the amount of C. officinalis extracts proposed for internal use by traditional medicine protects the organism against DNA damage induced by high PUFA intake.  相似文献   

4.
The metacestode of Taenia solium, Cysticercus cellulosae, was recovered from the brain of a cat showing central nervous clinical signs ante mortem. This is the first record of cerebral cysticercosis in a cat in South Africa.  相似文献   

5.
To understand the role of non-secreted components of Actinobacillus pleuropneumoniae in virulence, we investigated in vitro cytotoxicity and in vivo pulmonary changes in pigs due to various A. pleuropneumoniae (serotype 1) fractions. Following 1.5 h incubation, lipopolysaccharide (LPS), 2 crude extracts and bacterial culture supernatant (BCS) at high concentrations were cytotoxic to porcine pulmonary alveolar macrophages (PAM), peripheral blood mononuclear leucocytes, neutrophils and a cultured porcine bone marrow cell line. Heat-killed bacteria were cytotoxic to PAM after 24 h incubation. The 2 crude extracts were prepared by shaking either intact bacteria after removing culture supernatants (crude surface extract, CSE), or whole bacterial culture (crude surface plus culture supernatant extract, CSSE) with glass beads in saline at 60 degrees C. Further experiments showed that proteins from the bacterial membrane were partially involved in cytotoxicities of these 2 extracts. Both BCS and CSSE caused multivocal hemorrhage and neutrophil infiltration when inoculated into porcine lungs, but CSE did not. The lung:whole body weight ratios of the pigs treated with CSSE were significantly higher (P < 0.05) than those of pigs treated with BCS, CSE, or control solution. It is concluded that beside the secreted proteins, bacterial surface components including LPS and non-secreted proteins were cytotoxic in vitro; and secreted and non-secreted components act synergistically to cause lung lesions.  相似文献   

6.
OBJECTIVE: To use in vitro assays to evaluate the effects of a novel immunosuppressive agent, FTY720, on biological functions (migration, phagocytosis, and production of reactive-oxygen species [ROS]) of feline peripheral neutrophils and determine the cytotoxic effects of FTY720 on feline peripheral neutrophils. SAMPLE POPULATION: Peripheral neutrophils obtained from 8 healthy cats. PROCEDURE: Peripheral neutrophils were isolated from blood samples obtained from the 8 cats and exposed to the phosphorylated form of FTY720 (FTY720-P). A fluorescence-based in vitro evaluation of migration was performed. Phagocytosis of microbes and production of ROS were evaluated by use of a 2-color flow cytometry system. Samples of whole blood obtained from the cats were incubated with various concentrations of FTY720-P, fluorescein-labeled Staphylococcus aureus, and dihydroethidium. Cytotoxic effects were evaluated by use of propidium iodide staining. RESULTS: Addition of FTY720-P caused a slight non-significant decrease in phagocytosis and production of ROS by feline peripheral neutrophils. Migration activity of feline peripheral neutrophils was significantly increased by the addition of FTY720-P. Addition of FTY720-P at concentrations considered for clinical use did not increase the death rate of feline peripheral neutrophils. CONCLUSIONS AND CLINICAL RELEVANCE: FTY720 does not inhibit critical functions of feline peripheral neutrophils in vitro.  相似文献   

7.
2-Aminoethoxydiphenyl borate (2-APB) interferes with the Ca(2+) influx and reduces the ROS production, gelatinase secretion and CD11b expression in bovine neutrophils. Moreover, it has been suggested that inhibition of the Ca(2+) channel involved in the store operated Ca(2+) entry (SOCE) is a potential target for the development of new anti-inflammatory drugs in cattle, however it is unknown whether 2-APB affects neutrophil functions associated with the innate immune response. This study describes the effect of 2-APB, a putative SOCE inhibitor, on alkaline phosphatase activity a marker of secretory vesicles, CD63 a marker for azurophil granules, F-actin polymerization and in vitro chemotaxis in bovine neutrophils stimulated with platelet-activating factor (PAF). Also, we evaluated the effect of 2-APB in the phagocytic activity against Escherichia coli and Staphylococcus aureus bioparticles. We observed that doses of 2-APB ≥10 μM significantly reduced alkaline phosphatase activity and in vitro chemotaxis, whereas concentrations of 2-APB ≥50 μM reduced CD63 expression and F-actin polymerization. Finally, we observed that 2-APB did not affect the phagocytic activity in neutrophils incubated with E. coli and S. aureus bioparticles. We concluded that inhibition of Ca(2+) influx could be a useful strategy to reduce inflammatory process in cattle.  相似文献   

8.
Bovine fetal placental (cotyledon) tissue obtained from pregnant cows on days 255, 265, and 275 of gestation, as well as immediately after parturition (n = 5) was incubated in media for 48 hours, and the incubation media were collected. Neutrophils from 4 ovariectomized nonpregnant cows were incubated for 2 hours with conditioned media from placental tissue cultures or medium (control). Immediately after incubation, the neutrophils were subjected to the following leukocyte function assays: chemotaxis against zymosan-activated serum, chemotaxis against undiluted conditioned media (only neutrophils that were incubated in medium only), random migration, ingestion of 125I-iododeoxyuridine Staphylococcus aureus (125I-IdUR-S aureus), iodination of proteins, cytochrome C reduction, and antibody-independent and -dependent cell-mediated cytotoxicity. Conditioned media from cultured cotyledon tissue was chemoattractant for bovine neutrophils, and increased chemotactic response of neutrophils against zymosan-activated serum by 13%. The following neutrophil functions were decreased: random migration by 25%, iodination of proteins by 44%, cytochrome C reduction by 13%, and antibody-dependent cell-mediated cytotoxicity by 5%. Ingestion of 125I-IdUR-S aureus and antibody-independent cell-mediated cytotoxicity were not influenced by coincubation of neutrophils and conditioned media. Time of gestation did not alter the effects of conditioned media on neutrophil function. It was concluded that chemotactic properties of cotyledon tissue extracts, as has been reported earlier, may be attributable to substances released by fetal placental tissue. Those substances might also locally or systemically influence the oxygen-dependent antimicrobial system of neutrophils, thereby causing an increased susceptibility to bacterial infections in the peripartum period.  相似文献   

9.
The aim of this study was to verify whether the addition of catalase (20 IU/mL) at different steps of goat ovarian tissue vitrification affects ROS levels, follicular morphology and viability, stromal cell density, apoptosis and the expression of proteins related to DNA–damage signaling (γH2AX) and repair (53BP1). Goat ovarian tissues were analyzed fresh (control) or after vitrification: without catalase (VS–/WS–), with catalase in vitrification solutions (VS+/WS–), with catalase in washing solutions (VS–/WS+) or with catalase in both solutions (VS+/WS+). The vitrification without catalase had higher ROS levels than the control. The catalase, regardless the step of addition, maintained ROS levels similar to the control. There were no difference between treatments regarding follicular viability, stromal cell density and detection of γH2AX and 53BP1. There was no difference in follicular morphology and DNA fragmentation between groups vitrified. In conclusion, catalase addition to vitrification solutions prevents ROS formation in cryopreserved goat ovarian tissues.  相似文献   

10.
Thawed ram spermatozoa were incubated at 37°C in the presence of dehydroascorbic acid (DHA), TEMPOL (TPL), N‐acetyl‐cysteine (NAC) and rutin (RUT), at 0.1 and 1 mm , in order to test their effects on sperm physiology. Cryopreserved spermatozoa from four rams were thawed, pooled, washed and incubated in TALP‐Hepes with 1 mm or 0.1 mm of each antioxidant, performing a replicate with induced oxidative stress (Fe2+/ascorbate). Motility (CASA), viability and mitochondrial membrane potential (flow cytometry) were analysed at 2 and 4 h. Lipoperoxidation (MDA production), intracellular reactive oxygen species (ROS) and DNA status (TUNEL) were analysed at 4 h. Antioxidants, except DHA 0.1 mm , decreased motility and kinematic parameters, but had little effect on viability or mitochondrial activity. Except 1 mm DHA, the antioxidants reduced ROS at 4 h. Moreover, NAC 1 mm , rutin and TEMPOL reduced ROS and DNA damage in the presence of oxidative stress. N‐acetyl‐cysteine, rutin 1 mm and TEMPOL reduced lipoperoxidation in the presence of oxidative stress. However, DHA did not affect lipoperoxidation. At 1 mm , DHA increased DNA damage in the absence of oxidative stress. Dehydroascorbic acid effects could arise from spermatozoa having a low capacity for reducing it to ascorbic acid, and it may be tested in the presence of other antioxidants or reducing power. Future research should focus in testing whether the inhibition of motility observed for NAC, rutin and TEMPOL is reversible. These antioxidants might be useful at lower temperatures (refrigerated storage or cryopreservation) when their protective effects could be advantageous.  相似文献   

11.
采用Sephadex G-200层析技术纯化猪囊尾蚴头节抗原,用纯化抗原包被ELISA板,建立间接ELISA方法。通过各种条件优化,最终确定最佳试验条件为:抗原最适包被量为30mg/L;血清稀释度为1∶800;血清最佳反应时间为60min。结果表明,该方法具有较好的稳定性和重复性,可用于分泌抗猪囊尾蚴头节单克隆抗体杂交瘤细胞株的筛选。  相似文献   

12.
A Flow Cytometric method for the evaluation of the phagocytic capacity of bovine blood neutrophils is described. The neutrophils were isolated from bovine blood by a one step discontinuous gradient of Percoll. By this technique of isolation, 90 ± 2.8 % (mean ± s) of the granulocytes in the whole blood were recovered.Isolated neutrophils were incubated with FITC labeled S. aureus or zymosan particles in a ratio of 1:20 and 1:10, respectively, and a final serum concentration of 10 %. Phagocytosis was terminated after 15 min and the number of extracellular bacteria or zymosan particles and the percentage of phagocytic granulocytes were registered by Flow Cytometry (FCM). FCM and microscopic studies revealed that eosinophils play a minor role in the phagocytosis of bacteria. The neutrophils were the main population of the granulocytes which were actively phagocytic. Variation among cows in the ability of their blood neutrophils to phagocytize bacteria was evident.  相似文献   

13.
REASONS FOR STUDY: Xanthine oxidase (XO)-dependent production of superoxide anion and hydrogen peroxide, a characteristic of ischaemia-reperfusion injury, may contribute to the development of equine laminitis. OBJECTIVE: To determine the levels of XO and antioxidant enzymes (catalase, superoxide dismutase [SOD]) in the digital laminae of normal horses (CON) and horses in the developmental stage of laminitis using the black walnut extract (BWE) model. METHODS: Healthy horses (n = 12) were administered BWE (BWE group, n = 6), or water (CON group, n = 6) through a nasogastric tube. At the onset of leucopenia in the BWE-treated animals, all horses were anaesthetised, digital laminae and other samples collected rapidly and flash frozen, and the animals subjected to euthanasia. Extracts of the frozen tissues were assayed for the 2 conformational forms of xanthine: oxygen oxidoreductase (XOR), namely, xanthine dehydrogenase (XDH) and xanthine oxidase (XO), as well as the antioxidant enzymes, SOD and catalase. RESULTS: Extracts of liver, lungs and skin, but not digital laminae, from either CON or BWE-treated horses had endogenous SOD, whereas all had endogenous XO and catalase. The levels of XDH, XO and catalase were similar in extracts of laminae from CON and BWE-treated horses as was the ratio of XDH to XO in extracts. CONCLUSIONS AND POTENTIAL RELEVANCE: The absence of increased XO activity suggest against the involvement of this reactive oxygen intermediate-generating system in the development of laminar pathology in BWE-treated horses. Conversely, the absence of SOD from extracts of equine digital laminae, but not other tissues, suggests that the equine digital laminae are highly susceptible to damage by superoxide anion, produced, for example, by emigrant inflammatory leucocytes.  相似文献   

14.
利用浓度梯度SDS－聚丙烯酰胺凝胶电泳对猪囊尾蚴的囊液和虫体，猪带绦虫成虫的头颈节、成节、孕节，猪带绦虫的虫卵以及羊囊尾蚴的蛋白成分进行了对比分析。结果发现：囊液、虫体、头颈节、成虫、孕节、虫卵、羊囊尾蚴分别有35条（15．0－150．4kd）、44条（15．0－133．7kd)、22条（13．3－163．9kd)、19条（13．3－90．1kd)、19条（13．3－90．1kd)、30条（13．3－99．4）和38条（15．0－133．4kd)蛋白带；其中15．0kd和35．5kd两条共同抗原蛋白带，在猪带绦虫各阶段和羊囊尾蚴中含量最大的蛋白带同时也是阶段性的共同抗原蛋白带。这些结果为下一步的保护性抗原筛选奠定了基础。  相似文献   

15.
着重探讨了在水分胁迫条件下,一氧化氮对小麦叶片膜脂过氧化的影响。试验结果表明,低浓度的NO能够提高小麦叶片中抗氧化酶的活性,消除自由基,从而缓解水分胁迫造成的细胞膜脂过氧化损伤,而高浓度的一氧化氮降低了抗氧化酶的活性,使自由基的产生量增加,从而加重了膜的损伤。  相似文献   

16.
Cadmium (Cd) is a well-known hepatotoxic environmental pollutant. We used rat hepatocytes as a model to study oxidative damage induced by Cd, effects on the antioxidant systems, and the role of N-acetylcysteine (NAC) in protecting cells against Cd toxicity. Hepatocytes were incubated for 12 and 24 h with Cd (2.5, 5, 10 µM). Results showed that Cd can induce cytotoxicity: 10 µM resulted in 36.2% mortality after 12 h and 47.8% after 24 h. Lactate dehydrogenase, aspartate aminotransferase, and alanine aminotransferase activities increased. Additionally, reactive oxygen species (ROS) generation increased in Cd-treated hepatocytes along with malondialdehyde levels. Glutathione concentrations significantly decreased after treatment with Cd for 12 h but increased after 24 h of Cd exposure. In contrast, glutathione peroxidase activity significantly increased after treatment with Cd for 12 h but decreased after 24 h. superoxide dismutase and catalase activities increased at 12 h and 24 h. glutathione S-transferase and glutathione reductase activities decreased, but not significantly. Rat hepatocytes incubated with NAC and Cd simultaneously had significantly increased viability and decreased Cd-induced ROS generation. Our results suggested that Cd induces ROS generation that leads to oxidative stress. Moreover, NAC protects rat hepatocytes from cytotoxicity associated with Cd.  相似文献   

17.
The previous experiments have shown that some phenothiazines have antioxidant and anti-inflammatory properties in vitro . In this study the inhibition of the production of reactive oxygen species (ROS) by neutrophils was studied in two groups of horses, which received a dose of 0.1 mg/kg of either acepromazine or promethazine intravenously. Blood samples were collected before (T0) and 0.5, 1, 3 and 5 h after drug administration. The chemiluminescence (CML) response of neutrophils was measured ex vivo in the presence of luminol for a period of 10 min and the maximum CML value (peak value) recorded. There was a significant inhibition of the ROS production in the acepromazine treated group (49% inhibition) at 5 h after administration and in the promethazine group (24% inhibition) at 3 h after administration ( P  < 0.05 vs. T0). These findings are of therapeutic relevance in the use of phenothiazines in equine patients with inflammatory diseases where neutrophil activation and ROS production are implicated.  相似文献   

18.
通过附睾转运,精子经历了一系列的生化和形态变化逐渐成熟,在精子成熟的过程中,其胞质成分含量逐渐减少,因此精子对氧化应激更为敏感,进而导致精子结构和功能受到损害,故而附睾管腔微环境中抗氧化酶的作用非常重要。活性氧（ROS）在精子功能中起着双重作用：生理水平的ROS可促进精子受精前的获能,而过高水平ROS则会导致精子发生氧化损伤。在附睾中清除多余ROS的抗氧化酶主要有超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GPXs）以及过氧化物酶（PRDXs）,但是不同年龄的哺乳动物附睾不同部位中各种抗氧化酶的含量均会发生变化,不同抗氧化酶对ROS也具有不同的清除机制。当附睾缺乏某一抗氧化酶时,会使精子DNA受损、精子质量下降,最终导致异常生殖结果增加。因此,哺乳动物附睾中各类抗氧化酶需要相互协调将ROS维持在生理水平,但有关这方面的研究报道较少。附睾上皮细胞分泌的抗氧化酶以附睾小体的形式传递给精子,以清除自身有氧代谢以及异常精子所产生的ROS,进而保护精子正常成熟。作者综述了附睾精子所面临的氧化应激以及附睾中各类抗氧化酶对精子的保护作用。  相似文献   

19.
ObjectiveTo investigate the effect of acepromazine (ACP) on reactive oxygen species (ROS) production by stimulated equine neutrophils.Study designEx vivo biochemical experiments.AnimalsIsolated neutrophils from healthy untreated horses.MethodsNeutrophils were incubated with ACP at concentrations of 10?4, 10?5 or 10?6 m and then stimulated with phorbol-myristate-acetate (PMA) before measurement of lucigenin-enhanced chemiluminescence (CL). In a second experiment neutrophils were incubated in the presence of α-keto-γ methylthiobutyric acid (KMB) and treated with ACP at concentrations of 10?4, 10?5 or 10?6 m. Subsequent PMA stimulation lead to neutrophilic ROS production and decomposition of KMB to ethylene, which is measured by gas chromatography. Electron paramagnetic resonance-spin trapping (EPR) analysis was performed with PMA-stimulated neutrophils in the presence of ACP (10?4, 10?5 or 10?6 m) directly added to the cell suspension. In the second experiment, the same concentrations of ACP were pre-incubated with neutrophils, then centrifuged to eliminate the excess of ACP and re-suspended in phosphate buffer before stimulation with PMA. In all experiments, the results of ACP-treated and ACP-untreated stimulated neutrophils were compared.ResultsOverall, results obtained with lucigenin-enhanced CL and KMB oxidation were in agreement with those seen in electron paramagnetic resonance spectroscopy. Acepromazine induced a dose-dependent inhibitory effect on neutrophilic ROS production. Electron paramagnetic resonance also showed, at high ACP concentration, the appearance of a cation radical derived from ACP. In contrast, electron paramagnetic resonance study performed with pre-incubated neutrophils showed an important dose-dependent inhibitory effect of ACP.ConclusionThe results indicate that ACP can neutralize O˙?2 or its by-products during the stimulation of neutrophils.Clinical relevanceThese findings may have a therapeutic relevance when phenothiazines are used in horses suffering from inflammatory diseases in which neutrophil activation and ROS production are implicated.  相似文献   

20.
OBJECTIVE: To examine apoptosis in infiltrated neutrophils during involution of mammary glands and compare them with those obtained during late and peak lactation, and to measure oxidative stress and activities of antioxidant enzymes and determine involvement of free radicals in apoptosis of infiltrated neutrophils. SAMPLE POPULATION: Neutrophils from mammary gland secretions of 8 goats at 4 stages (late and peak lactation and 1 and 2 weeks after end of lactation). PROCEDURE: DNA fragmentation was evaluated to characterize apoptosis. Concentration of thiobarbituric acid reactive substances (TBARS) was used to evaluate oxidative stress. Activities of superoxide dismutase and glutathione peroxidase were determined. RESULTS: Neutrophils from secretions obtained after end of lactation of all goats and from late-lactation milk of some goats underwent prominent apoptosis, whereas neutrophils from peak lactation secretions did not. Higher lipid peroxidation and lower antioxidant enzyme activities in neutrophils during involution were observed, compared with those during late and peak lactation. A significant negative correlation existed between TBARS concentrations and antioxidant enzyme activities during the nonlactating period. CONCLUSIONS AND CLINICAL RELEVANCE: Apoptosis is a feature of infiltrated neutrophils during involution of mammary glands in goats. This feature may allow prompt resorption and clearance of infiltrated neutrophils without damaging surrounding tissues. Increased oxidative stress in infiltrated neutrophils from secretions obtained after end of lactation is probably related to a deficiency in antioxidant enzyme activities. Understanding the relationship between apoptosis and oxidative stress will lead to new strategies for manipulating involution and reducing tissue damage.  相似文献   

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