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Aims: To better understand the physiological and biochemical mechanisms in the light of antioxidative enzymes activity under salinity stress between tolerant and susceptible genotypes of groundnut. Study Design: Completely Randomized Design. Place and Duration of Study: The laboratory experiment was carried out in the departmental laboratory of Plant Physiology, Bidhan Chandra Krishi Viswavidyalaya (BCKV), Mohanpur, Nadia, and West Bengal during the year 2017-18. Methodology: A controlled study was conducted to screen 26 genotypes of groundnut under 200 mM NaCl salinity stress. Fourteen-day old seedlings were subjected to salinity treatment. For this, the modified Hoagland nutrient solution containing 200 mM NaCl (osmotic potential: -0.8 MPa) was applied in each case and the pH was adjusted to 6.3. The treatments were repeated on every third day. Control set without salinity stress was also maintained similarly in each case for comparison of results. Results: The salt tolerance index or STI of the genotypes ranged from 47.57% to 96.40%. Out of all the genotypes KDG-197 (STI= 96.40%) was found to be the most tolerant under a salinity stress of 200 mM NaCl and it was closely followed by R 2001-2 (STI=87.92%), VG 315 (STI=84.05%), TCGS 1157 (STI=77.59%) and TG 51 (STI=73.67%). While the genotypes Girnar 3 (STI= 47.57%), OG 52-1 (STI=49.09%), TVG 0856 (STI= 49.28%) and J 86 (STI= 50.66%) were the most susceptible genotypes based on their relative performance under stress in respect of total dry weight. It has been noted further that, out of the nine genotypes, enhancement of antioxidative enzyme like super oxide dismutase (SOD), guaiacol peroxidase (GPOX) and catalase (CAT) activity was recorded maximally in tolerant genotype KDG 197 (64.18%, 71.74% and 52.82% increase over control respectively) and R 2001-2 (53.68 %, 93.48% and 53.96 % increase over control respectively) but the activity of these enzyme in the four susceptible genotypes declined considerably under salinity treatment. Conclusion: Tolerant genotypes of groundnut in general registered much higher activities of antioxidative enzymes in their leaves as compared to the susceptible genotype under high salinity stress.
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To investigate the protective effects of ginkgo diterpene lactone meglumine injection (GDLMI) on cerebral focal ischemia reperfusion injury induced by middle cerebral artery occlusion (MCAO) in rats, and explore its possible mechanism. One hundred and forty male SD rats were randomly divided into sham operation group, model group, ginkgo biloba extract injection (Ginaton, 1.0 mL•kg⁻¹) group, nimodipine (0.4 mg•kg⁻¹) group, and GDLMI (5.2, 2.6, 1.3 mg•kg⁻¹) groups; All of rats received corresponding drugs by tail vein injection 4 days before operation (normal saline in model group and sham operation group). Except the sham operation group, the cerebral ischemic stroke model was established by MCAO method in right brain of the other rats. After 3 h of ischemia, all the animals received intravenous administration again. The neurobehavioral scores of rats after ischemia-reperfusion were evaluated and the infarct rate of brain tissue was observed by TTC staining. The super oxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA) and lactic acid (LA) contents in brain tissue homogenate and the concentration of Ca2+, glutamate (Glu) and aspartate (Asp), creatine phosphate kinase (CK-BB) and lactate dehydrogenase (LDH) content changes in cerebrospinal fluid were measured. As compared with the sham operation group, the cerebral infarction rate was increased significantly in the model group; the content of MDA and LA in the homogenate of brain tissue was increased, and the content of GSH and SOD was decreased; in cerebrospinal fluid, Ca2+ concentration was decreased, and the content of Glu and Asp, CK-BB and LDH increased significantly. As compared with the model group, the high and medium dose GDLMI groups can significantly reduce the cerebral infarction rate and improve the symptoms of neurological impairment; increase SOD and GSH activity, reduce MDA and LA content in serum; increase Ca2+ concentration in cerebrospinal fluid and decrease the content of neurotransmitter Glu and Asp as well as CK-BB and LDH. GDLMI could obviously improve neurologic impairment in model rats, and the mechanism may be related to recovering the blood brain barrier, scavenging free radicals, decreasing free Ca2+ inflow into the cells and the content of excitatory amino acid in cerebrospinal fluid to improve its protective effect on cerebral ischemia.
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OBJECTIVE: To explore the effect of zinc oxide nanoparticles(ZnO NPs) on the oxidative damage in human alveolar type Ⅱ epithelial cell line A549.METHODS: The A549 cells in logarithmic growth phase were incubated with ZnO NPs solution at dose of 0,10,20 and 40 mg/L as 4 dose groups.The levels of reactive oxygen species(ROS) were measured by flow cytometer after 4 hours of exposure.The malondialdehyde(MDA) content and super oxide dismutase(SOD) activity were measured by microplate reader after 8 hours of exposure.RESULTS: The ROS levels in A549 cells exposed to 10,20,40 mg/L ZnO NPs were significantly increased compared with control group(P<0.05).The level of ROS increased with the exposure dose of ZnO NPs in A549 cells(P<0.01).The activities of SOD in A549 cells exposed to 10,20,40 mg/L ZnO NPs were significantly decreased compared with control group(P<0.05).The level of MDA and the ratios of MDA/SOD increased compared with control group(P<0.05).The activity of SOD in A549 cells decreased with the increase of ZnO NPs exposure dose(P<0.01),and the level of MDA and the ratios of MDA/SOD increased with the increase of exposure(P<0.01).CONCLUSION: ZnO NPs could induce lipid peroxidation in A549 cells with a dose-effect relationship.
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Objective To study the protective effect of rose (Rosae Rugosae Flos) essential oil on acute myocardial infarction in mice, and explore its mechanism. Methods The model of acute myocardial ischemia in mice was established by intraperitoneal injection of isopropyl adrenaline. The myocardial tissue pathological changes and the degree of myocardial injury in mice were observed by HE staining and TTC staining. Activities of super oxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in myocardial tissue of mice were determined, and activities of creatine kinase isoenzyme (CK-MB) and lactate dehydrogenase (LDH) in serum of mice were determined as well. Results HE staining results showed that rose essential oil group (160, 80, and 40 mg/kg) can significantly improve myocardial tissue pathological injury in mice; TTC staining results showed rose essential oil (160, 80, and 40 mg/kg) can significantly reduce the myocardial ischemia areas in mice. Compared with model group, SOD and GSH-Px in the myocardial tissue of mice significantly increased (P < 0.05, 0.01), while enzyme activity of serum LDH and CK-MB significantly reduced in rose essential oil group (P < 0.05, 0.01). Conclusion Rose essential oil has certain protective effect on acute myocardial infarction injury and its mechanism may be associated with inhibiting oxidative damage, enhancing activities of anti-oxidant enzymes, and reducing the lipid peroxidation damage.
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Objective To observe the intervention effects of methylprednisolone (MPred) to acute lung injury(ALI) model of rats induced by oleic acid.Methods Thirty of Sprague-Dawley rats were randomly divided into three groups which were normal control group (NC,n =6),oleic acid model group (n =12),and MPred group (n =12).Rats were injected with oleic acid at dose of 0.1mg/ kg via caudal vein and then ALI model was established.The rats of NC group were injected with 0.1 mg/kg of normal saline instead of oleic acid.In NC group rats were sacrificed by blood collection at 6h after NS injection.Blood samples and tissues were collected and stored freezing.Samples of the other groups were collected at 2h and 6h after the last treatment.The observation indexes are histomorphology of lung tissue,the wet and dry weight of lung (W/D),index of quantitative assessment (IQA) score,partial pressure of oxygen in artery (PaO2),and SOD,MDA,MMP-9 and TIMP-1 levels in the blood plasma and lung tissue.Results Lung surface hyperemia relieved obviously and pink secretion from trachea of rats in MPred group decreased compared with oleic acid model group.In light microscope,compared with oleic acid model group,effusion of inflammatory cell in alveolar space of rats in MPred group eased.W/D of rats in oleic acid model group advanced obviously compared with that in NC group,W/D of rats in medrol group lowered obviously compared with that in oleic acid model group.IQA scores of rats in oleic acid model group advanced obviously compared with that in NC group,IQA score of rats in MPred group lowered obviously compared with that in oleic acid model group.PaO2 of rats in oleic acid model group lowered obviously compared with that in NC group,PaO2 of rats in MPred group advanced obviously compared with that in oleic acid model group.The level of SOD in plasma and lung tissue of rats in oleic acid model group lowered obviously compared with that in NC group,SOD level in plasma and lung tissue of rats in MPred group advanced obviously compared with that in oleic acid model group.The level of MDA in plasma and lung tissue of rats in oleic acid model group lowered obviously compared with that in NC group,MDA in plasma and lung tissue of rats in MPred group advanced obviously compared with that in oleic acid model group.Compared with the NC group,the level of MMP-9 in the plasma and lung tissue of oleic acid induced ALI rats increased and TIMP-1 levels decreased significantly.The level of MMP-9 in the plasma of rats decreased and TIMP-1 level increased significantly in MPred group at 2h and 6h.Conclusion MPred can improve lung pathological injury,increase PaO2 level,decrease lung W/D ratio and IQA scores by modulating the level or activity of the SOD and MDA and MMP-9 and TIMP-1 in the plasma and lung tissues.It is speculated that the effects of anti-inflammation and anti-exudation of sodium aescinate may due to affecting on oxidative stress response as well as the decomposition and remodeling of extracellular matrix during inflammatory lung injury of acute lung injury rats.
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Background: Age related hearing loss is an universal feature of mammalian ageing and refers to sensorineural hearing impairment in elderly individuals. It was reported that increased generation of free radicals during cellular metabolism plays a major role in age related disorders. Therefore, the occurrence of age related hearing loss depends mainly on antioxidant status of the body. Hence, this study was undertaken to investigate the status of Glutathione and Superoxide dismutase in age related hearing loss. Methods: This study was conducted after the approval from institutional ethical committee. The study group included 25 patients diagnosed for age related hearing loss between the age group of 55-80 years of either sex and 25 healthy age and sex matched individuals as controls. Estimation of Glutathione was done by DTNB method and Superoxide Dismutase using standard procedures. The data was analysed using One Way ANOVA. P value less than 0.05 will be considered the level of significance. Results: The results showed that, the Glutathione level in Hearing Loss patients was increased significantly (p=0.0001) as compared to normal controls. The SOD Activity has declined significantly (p=0.001) in Hearing Loss patients as compared to normal controls. Conclusion: We found an association between the level of Glutathione and Super Oxide Dismutase in age related hearing loss. Thus the serum Glutathione and Super Oxide Dismutase level can be used as a biomarker for the assessment of age related hearing loss.
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Objective Through the UVB rays radiation skin injury model ,the study investigated the effect of seabuckthorn flavonoids on the protection and restoration of the skin ,in order to provide experimental basis of looking for the new drugs against ultraviolet injury .Methods By UVB radiating repeatedly ,the study built UVB radiation skin injury model in mice ,to observed the morphological changes of the skin in every groups of experimental animal ,the super oxide dismutase (SOD) activity of the skin and the peroxidation damage degree of the skin lipid ,which is also the content changes of malondialdehyde (MDA) and collagen .Results The change of model group whose epidermis layer increased and the dermis thickened was more obvious than the normal group ,so the UVB radiation skin injury model was built successfully .The model group compared with the normal group ,its SOD activity was significantly lower and its MDA content was significantly higher (P< 0 .01) .However ,the SOD activities of positive control group and being fed with seabuckthorn flavonoids group were significantly higher and their MDA contents were significantly lower (P<0 .01) .The model group compared with the normal group ,its collagen content was significantly lower (P< 0 .05) ,and the collagen contents of positive control group and being fed with seabuckthorn flavonoids group were higher ,whose difference was extremely significant(P< 0 .01) .However ,the positive control group had hyperplastic scar .Conclusion Seabuckthorn flavonoids had the fol‐lowing effects :preventing the UVB repeating radiation damage to the skin ,improving the SOD activity of skin tissue and the colla‐gen content ,inhibiting the increase of MDA content and scar hyperplasia ,and having antagonism effect of UVB causing mice skin photoaging .
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Objective To investigate the protective effect and its mechanism of DL-3-n-Butylphthalide on the brain damage in rats following whole brain irradiation.Methods A total of 120 male Sprague Dawley rats were randomly divided into sham-irradiation group,irradiatien group and DL-3-n-Butylphthalide group.The model of whole-brain irradiatien was established by exposuring rat brain to 4 MeV X-rays with a single-dose of 10 Gy.The rats were intraperitoneally injected with DL-3-n-Butylphthalide at the dosages of 0.3,1.0,and 3.0 mg/kg once a day.The contents of malondialdchyde and super oxide dismutase activity were measured,while the expressions of apoptosis-associated genes and the ultrastructural changes in hippocampus were examined by immunohistnchemisty staining and electron microscope,respectively.Results After irradiation,the content of malondialdehyde and the expression of apoptosis gene bax in rat brain tissue increased while the activity of super oxide dismutase(SOD) and the expression of anti-apoptosis gene bcl-2 decreased.Apoptosis was also observed in the neurons of hippocampus CA1.Compared with irradiation group,the content of malondialdehyde and the expression of bax gene in the DL-3-n-Butylphthalide group wen significantly reduced ( t =-3.89--1.96,2.72-3.48,P ＜ 0.05 ),while the activity of SOD and bcl-2 gene were significantly elevated ( t =2.94-3.76,-3.18--2.08,P ＜ 0.05),and the injury degree of neuron structure in the DL-3-n-Butylphthalide group was slighter than that in the irradiation group.Conclusions DL-3-n-Butylphthalide executes protective effects in a dose-dependent manner againest the radiation injury in rats brain by reducing the induction of malondialdehyde,raising the activity of SOD and inhibiting the generation of apoptosis.
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Objective To investigate the effect ofYindanxinnaotong (YDXNT) capsule on learning and memory abilities, super oxide dismutase (SOD) activity and malondialdehyde (MDA) content in the hippocampus of rat models of vascular dementia (VD). Methods Animals were randomly divided into sham-operated group,VD vehicle group (Group VD) and YDXNT treatment group (Group VD+YDXNT); the 4-vessel occlusion was employed to establish the VD rat models in the Group VD and Group VD+YDXNT,while rats in the sham-operated group were not performed occlusion of the bilateral common carotid artery.Rats of the Group VD+YDXNT were given 1 mL liquid (9 granules of YDXNT into 360 mL normal saline) through intragastric administration 3 times daily for a consecutive 4 weeks; and rats of the other 2 groups were given the same volume of saline.The changes of learning and memory abilities were observed by Morris water maze test; the activity of SOD and the content of MDA in the hippocampus were measured. Results As compared with those in rats of the Group VD, the learning and memory abilities in rats of the Group VD+YDXNT were significantly improved (P＜0.05):time in finding the platform was obviously decreased and swimming distance in finding the platform was obviously shortened in rats of Group VD+YDXNT.As compared with those in rats of the Group VD,the activity of SOD in the hippocampus was significantly increased and the content of MDA was obviously decreased in rats of the Group VD+YDXNT (P＜0.05). Conclusion YDXNT could increase oxygen radical metabolism to improve the learning and memory abilities of rats with VD.
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@#ObjectiveTo investigate the effects of morroniside on super oxide dismutase (SOD) and neurons in rats cortex with focal cerebral ischemia/reperfusion. MethodsThe animal model was induced by middle cerebral artery occlusion with suture embolus, cerebral ischemia 30 min and reperfusion 3 d or 7 d. Vitamin E for the positive control. The content of SOD was detected with spectrophotometry and the nerve cells was observed with immunohistochemistry. ResultsCompared with model group, morroniside （270 mg/kg）increased the activity of SOD and the number of neurons （30 mg/kg, 90 mg/kg, 270 mg/kg） significantly. ConclusionMorroniside may have neuroprotective effect and increasing the activity of SOD in rats cortex.
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Objective To explore the prevention and treatment effect and its mechanism of Xuebijing injec-tion combined with dexamethasone on rats' paraqnat-induced acute and chronic pulmonary injury.Method One hundred and twenty of male Wistar rats were randomly divided into six groups:nomud group(A),administrated with saline;model group(B)and treatment groups(group C,D,E,F)were given 20%PQ(100 mg/kg.ip),and 2 hours later the normal and model groups were administrated with the same volume of saline for treatment,rats in group C and group D received 1.25 g/kg and 2.5 g/kg Xuebijing injection respectively.rdts in group E received 25,ng/kg dexamethasone,rats in group F receired 2.5 g/kg Xuebijing injection combined with 2.5 g/kg dexamethasone,one time per day till to be killed,while rats killed at 28 d were treated for 7 days.At 2 d,3 d,4 d after poisoned,five rats in each group were killed,serum SOD,MDA level and arterial gas(at 3 d)were measured.At 28 d,the rest of rats were killed,and serum TGF-β1,lung tissure HYP were measured.The pathology of the lung tissue was ob-served at 3 d and 28 d in guoup A,B,F.Results Compared with group B,poisoning symptoms in the treatment groups were milder and serum.SOD,MDA,TGV-β1,lung tissure HYP level were better,arterial oxygen content were higer.Among treatment groups,the treatment effects in group F were the best,SOD and MDA of 3 d,HYP and TGF-β1 of 28 d in group B and F were respectively(37.47±13.00,91.86±21.35)nmol/mL;(11.34±3.07,5.63±1.58)nmoL/mL;(2.54±0.63,1.32±0.07)mg/g;(484.13±63.79,202.22±49.83)pg/mL.The difference was significant(P＜0.05).The pathology of the lung tissue showed that acute lung hemorrhage,edema or chronic pulmonary fibrosis in group F were milder than that of group B.Conclusions In early stage,Xuebijing injection combined with dexamethasone has a stronger ability to clear out oxidized free radical and inhibit lipid super oxidized reaction.This may ameliorate acute pulmonary blooding and edema.In later stage,they could ameliorate chronic pulmonary fibrosis by inhibiting TGF-β1 secretion and HYP generation.
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Aim To observe the intervention effects of sodium aescinate on acute lung injury model of rats induced by oleate. Methods Fifty four male SD rats were randomly divided into five groups: normal control group, sodium aescinate control group (without oleate) , oleate model control group,medrol interventional group and sodium aescinate interventional group. Acute lung injury models of rats were made by injecting oleate (OA, 0. 1 ml · kg~(-1) ) through caudal veins, and then rats were observed and killed to detect correlated in-dice. The observation indice were the histomorphology of lung, the wet and dry weights of lung ( W/D), score of injury of lung under light microscope (IQA ) , partial pressure of oxygen in artery ( PaO_2) , the levels of SOD and MDA in blood plasma and lung tissue. Results ① Histomorphology of lung: Lung surface hyperemia relieved obviously and pink secretion from trachea of rats in sodium aescinate interventional group and medrol interventioal group decreased significantly compared with oleate model control group. Under light microscope , compared with oleate model control group, effusion of inflammatory cells in alveolar space of rats in sodium aescinate interventional group and medrol interventional group decreased. ② The wet and dry weights of lung ( W/D ) ; W/D of rats in oleate control model group increased obviously compared with those in normal control group, W/D of rats in sodium aescinate interventional group and medrol interventional group decreased obviously compared with those in oleate model control group. ③ Score of injury of lungs under light microscope (IQA) ; IQA of rats in oleate model control group advanced obviously compared with that in normal control group. IQA of rats in sodium aescinate interventional group and medrol interventional group lowered significantly compared with that in oleate model control group.④ Partial pressure of oxygen in artery (PaO_2) : PaO_2 of rats in oleate model control group lowered significantly compared with that in normal control group. PaO_2 of rats in sodium aescinate interventional group and medrol interventional group improved significantly compared with that in oleate model control group. ⑤ The levels of SOD and MDA in blood plasma and lung tissue:The levels of SOD in plasma and lung tissue of rats in oleate model control group lowered significantly compared with those in normal control group. SOD in plasma and lung tissue of rats in sodium aescinate in-terventional group and medrol interventional group increased significantly compared with that in oleate model control group. The levels of MDA in plasma and lung tissue of rats in oleate model control group lowered significantly compared with those in normal control group. MDA in plasma and lung tissue of rats in sodium aescinate interventional group and medrol interventional group increased significantly compared with that in oleate model control group. Conclusion Sodium aescinate can improve W/D, IQA and PaO_2 by adjusting oxidization of the acute lung injury model of rats, which may provide a possible path for treating acute lung injury in clinical practice.
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Objective To investigate the effect of telmisartan on the oxidative stress induced by high glucose in human umbilical vein endothelial cell (HUVEC) in vitro.Methods HUVEC were cocultured with telmisartan (1?10~(-6) mol/L) and various concentration of glucose(5,30 mmol/L) for 0,12,24,36,48 h respectively. The level of MDA in the supernatants of cultured endothelial cells was measured by thiobarbituric acid test,SOD was determined by xanthine oxidase test.The protein expression of peroxisome proliferator activated receptors ? (PPAR-?) in HUVEC 24 h was assessed by Western blot after treatments.Results High glucose significantly increase the levels of MDA (before:1.2?0.06 vs after:1.6?0.1 mmol/mL,P
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80) via portal vein.After reperfusion 1 h,1 d,3d and 7 d respectively,the concentration of superoxide dismutase(SOD) and catalase(CAT) were tested,and the apoptosis of hepatocarcinoma also was observed using terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling(TUNEL) method.Results The results indicated that the SOD concentration in both hepatocarcinoma tissue and normal hepatic tissues decreased following I/R and perfusion with hyperoxic fluid liquid.The concentration of CAT increased following I/R in normal hepatic tissues.In hepatocarcinoma tissue,concentration of CAT decreased after reperfusion for 1 d and reached its lowest point.After perfusion with hyperoxic fluid,the concentration of SOD in both hepatocarcinoma tissue and normal hepatic tissues decreased more quickly following I/R and the low level was still found on 7 d after reperfusion.The concentration of CAT in tissues of both groups decreased and reached the lowest level at 1 h after reperfusion,but it was restored at 3 d reperfusion in normal hepatic tissues,and in hepatocarcinoma tissue was still at lower level until 7 d after reperfusion. After I/R,the apoptotic cells increased in normal hepatic and hepatic cancer tissues,and were most marked in tissues of hepatic carcinoma at 1 d and 3 d after perfusion with hyperoxic fluid.After I/R and perfusing with hyperoxic fluid,the changes of SOD and CAT and apoptosis in hepatocarcinoma tissue were more obvious than that in normal hepatic tissues(P
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Objective To explore the regularity of damage of anti-lipid peroxidation by air pollutants, and to provide experimental basis for revealing the pathogenetic mechanism of air pollutants. Methods 80 Wistar rats weighting 180-200 g were randomly and averagely divided into 4 groups, ie control group, lower dose group, middle dose group and higher dose group, which were exposed to particulate, SO2 and NO2 respectively. The rats in lower dose group, middle dose group and higher dose group were perfused by 1 ml normal saline mixed with 7.5, 15 and 30 mg particulate respectively, while the rats in control group were only perfused with 1 ml normal saline. At the 2nd day after exposure to particulate, the rats in 3 dose groups were exposed to the mixed air of SO2 and NO2. The lower, middle, and higher dose group were exposed to mixed air of SO2 and NO2 at the concentrations as following: 8 and 5 mg/m3, 16 and 10 mg/m3, 32 and 20 mg/m3 respectively while the control group was exposed to fresh air two hour per day, continuously for 7 days. Half of the rats in each dose group were killed at the 1st day after the 7-day exposure to SO2 and NO2 , the rest were killed at the 8th day after the 7-day exposure to SO2 and NO2 . The contents of MDA, the activities of GST and SOD in serum, the activities of SOD and the contents of MDA in BALF were measured. Results At the 1st day after the exposure to SO2 and NO2 , lower activities of SOD and GST, and higher contents of MDA in serum of rats were observed in higher dose group compared with those in control group. At the 8th day after the exposure to SO2 and NO2 , significantly lower SOD activities were still observed in higher dose group compared with those in control group. It revealed that higher concentrations of air pollutants could decrease the activities of anti-oxidase and increase the contents of lipid peroxides in serum of rats. However, the SOD activities in BALF showed no significant differences among different dose groups at different time during the exposure period. Higher contents of MDA in BALF of rats were observed in higher dose group at the first day after the exposure to SO2 and NO2 , and in middle and higher dose group at the 8 th day after the exposure to SO2 and NO2 compared with those in control group (P
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Objective To observe the cardioprotective effects of hyperoxia liquid by comparing the changes of blood concentrations of malondialdehyde(MDA)and super oxide dismutase(SOD)in mechanical heart valve replacement.Methods Thirty patients required mechanical heart valve replacement were randomly divided into hyperoxia liquid group(Group HL) and control group 15 cases in each.From the start of skin incision(T_(0)) to(10min) after CPB,patients received 10mL/kg Ringer's injection(control group) and 10mL/kg hyperoxia liquid(Group HL) seperately.The central venous blood samples,which were collected in both groups respectively at skin incision(T_(0)),1h after start of CPB(T_1),2h(T_2) and 24h(T_3) after aorta off-clamping,were used to test the blood concentrations of SOD and MDA.Also a series of clinical data were recorded,such as the rate of heart automatic rebeat after aorta off-clamping,ventricular arrhythmia,usage of dopamine in operation and postoperation.(Results)In both groups,the blood concentrations of MDA and SOD were all within normal range before operation.MDA level at T_(2) was lower in Group HL than that in control(P