Nitric oxide(NO),which generally originates from vehicle exhaust and industrial flue gases,is one of the most serious air pollutants.In this case,the electrochemical NO reduction reaction(NORR)not only removes the atm...Nitric oxide(NO),which generally originates from vehicle exhaust and industrial flue gases,is one of the most serious air pollutants.In this case,the electrochemical NO reduction reaction(NORR)not only removes the atmospheric pollutant NO but also produces valuable ammonia(NH_(3)).Hence,through the synthesis and modification of Fe_(3)C nanocrystal cata-lysts,the as-obtained optimal sample of Fe_(3)C/C-900 was adopted as the NORR catalyst at ambient conditions.As a result,the Fe_(3)C/C-900 catalyst showed an NH_(3)Faraday efficiency of 76.5%and an NH_(3)yield rate of 177.5μmol·h^(-1)·cm^(-2)at the working potentials of-0.8 and-1.2 V versus reversible hydrogen electrode(vs.RHE),respectively.And it delivered a stable NORR activity during the electrolysis.Moreover,we attribute the high NORR properties of Fe_(3)C/C-900 to two aspects:one is the enhanced intrinsic activity of Fe_(3)C nanocrystals,including the lowering of the energy barrier of rate-limiting step(*NOH→*N)and the inhibition of hydrogen evolution;on the other hand,the favorable dispersion of active components,the effective adsorption of gaseous NO,and the release of liquid NH_(3)products facilitated by the porous carbon substrate.展开更多
Nitric oxide(NO) from flue gas is hard to remove because of low solubility and reactivity. A new technology for photocatalytic oxidation of NO using ultraviolet(UV)/TiO2/H2O2 process is studied in an efficient laborat...Nitric oxide(NO) from flue gas is hard to remove because of low solubility and reactivity. A new technology for photocatalytic oxidation of NO using ultraviolet(UV)/TiO2/H2O2 process is studied in an efficient laboratory-scale reactor. Effects of several key operational parameters on NO removal efficiency are studied, including TiO2 content, H2O2 initial concentration, UV lamp power, NO initial content, oxygen volume fraction and TiO2/H2O2 solution volume. The results illustrate that the NO removal efficiency increases with the increasing of H2O2 initial concentration or UV lamp power. Meanwhile, a lower NO initial content or a higher TiO2/H2O2 solution volume will result in higher NO removal efficiency. In addition, oxygen volume fraction has a little effect.The highest NO removal efficiency is achieved at the TiO2 content of 0.75 g/L, H2O2 initial concentration of 2.5 mol/L, UV lamp power of 36 W, NO initial content of 206×10-6 and TiO2/H2O2 solution volume of 600 m L. It is beneficial for the development and application of NO removal from coal-fired flue gas with UV/TiO2/H2O2 process.展开更多
In order to investigate the effects of nitric oxide(NO) on the growth and development of porcine preantral follicles,we treated the follicles with different concentrations of sodium nitroprusside(SNP,0, 0.001,0.01,0.1...In order to investigate the effects of nitric oxide(NO) on the growth and development of porcine preantral follicles,we treated the follicles with different concentrations of sodium nitroprusside(SNP,0, 0.001,0.01,0.1 and 1 mmol/L),a NO donor.The results showed that the follicle diameter increased during in vitro culture,but there were no significant differences between the treatments(P】0.05);the survival rate in the 1 mmol/L SNP group was significantly lower than that in the 1μmol/L SNP group(61.61% vs 81.52%,P【0.05),but no significant differences were found between other treatments(P】0.05);the rate of antrum formation in the 1μmol/L SNP group peaked at 50%on day 4,and the rate in the 1μmol/L SNP group on day 6 was higher than that in the 0.01 mmol/L SNP group;in addition,the rate of antrum formation in the 1μmol/L SNP group was significantly higher than that in the 0.1 and 1 mmol/L SNP groups (Day 6:73.07%vs 50%,47.62%,P【0.05).After 6 days of culture,the proportion of normal oocytes in the1 mmol/L SNP group was significantly lower than that in the 1μmol/L SNP group(71.21%vs 48.18%, P【0.05),with no significant differences between other treatments(P】0.05).The recovery rate of cumulus cells oocyte complexes(COCs) in the 1μmol/L SNP group was significantly higher than that in the controls and all other treatments(37.27%vs 22.88%,25.59%,20.74%and 19.39%,P【0.05).The results indicate that during the in vitro culture of porcine preantral follicles,low concentration of NO released from SNP improves growth and development of oocytes and follicular antrum formation while high levels of NO are toxic to follicular survival.展开更多
Subclinical endometritis is a physiological inflammation that serves to clear persistent contaminants from the uterus. To investigate the alteration of antioxidant, such as vitamin E（VE） and vitamin C（VC）, total o...Subclinical endometritis is a physiological inflammation that serves to clear persistent contaminants from the uterus. To investigate the alteration of antioxidant, such as vitamin E（VE） and vitamin C（VC）, total oxidant capacity（TOC） and nitric oxide（NO） in cows with normal and subclinical endometritis（SCE）, we examined the concentrations of NO, VC and VE, TOC and polymorphonuclear neutrophils（PMN） percentage in uterine secretion. The cows were divided into two groups, normal（n=20） and subclinical endometritis（SCE, n=60）, based on endometrial cytology（presence of PMN≥5%）. Uterine secretion and blood were collected as described previously. Griess reaction was used to determine the concentration of NO. The concentrations of TOC, VC and VE were detected by a commercially available assay kit. The results showed that the concentrations of NO, TOC and PMN percentage were significantly higher（P〈0.01, P〈0.05, and P〈0.01, respectively） in uterine secretion with SCE compared to those from normal; however, the levels of VC and VE were significantly lesser（P〈0.01）. In conclusion, the concentrations of NO, TOC, VC, VE and PMN percentage differed between normal and SCE cows. Meanwhile, the relationship between the concentration of NO and PMN percentage from uterine secretion in cows with subclinical endometritis were positively correlated. Consequently, these alterations in NO, TOC, VC, VE levels and PMN percentage contributed to as a diagnostic index of the uterine inflammation, with the aim to increase the reproduction of the cows and the decrease economic losses.展开更多
OBJECTIVE To investigate the regulation of {O^2(2,4-dinitrophenyl)1-[(4-ethoxycarbonyl)piperazin-1-yl]diazen-1-ium-1,2-diolate}(JS-K),anitric oxide donor,on tumor energy metabolism in H22 tumor-bearing mice.METHODS Th...OBJECTIVE To investigate the regulation of {O^2(2,4-dinitrophenyl)1-[(4-ethoxycarbonyl)piperazin-1-yl]diazen-1-ium-1,2-diolate}(JS-K),anitric oxide donor,on tumor energy metabolism in H22 tumor-bearing mice.METHODS The hepatoma animal model in BALB/c mice was established with H22 cell line.The JS-K group and model group were received JS-K(0.75 and 1.5 mg?kg^(-1)) and saline via tail intravenous once every 3 d for 14 d,received 5 injections,respectively.The positive group was received 5-FU 20 mg·kg^(-1) by intraperitoneal injection once a day for 14 d.On the 15 th day mice were sacrificed.The tumor growth inhibition rate were calculated.The activities of hexokinase(HK),phosphofructo kinase(PFK),pyruvate kinase(PK),succinate dehydrogenase(SDH),adenosine triphosphatase(ATPase),and the levels of lactic acid(LD) and adenosine triphosphate(ATP) in tumor tissues were determined by colorimetric method.RESULTS Compared with model group,the tumor mass of JS-K0.75 and 1.5 mg·kg^(-1) group was significantly reduced(P<0.01),and the tumor growth inhibition rate was 23.9% and 50.3%,respectively.The activity of HK,PFK,PK,SDH and ATPase of tumor tissue in model group was(22.6±3.7,14.4±2.6,12.9±3.2 and 10.5±2.6)U·g^(-1) protein and(0.70±0.10)μmol Pi·mg^(-1) protein per hour,respectively;which in JS-K 1.5 mg?kg^(-1) group was dropped by 42.0%,26.6%,22.7%,23.3% and 21.7%(P<0.01,P<0.05).Compared with the model group,the level of ATP and LD in JS-K group was dropped(P<0.01).CONCLUSION JS-K can inhibit the growth of tumor in H22 tumor-bearing mice and its mechanism may be related to regulating the tumor energy metabolism with inhibition of glycolysis and aerobic oxidation.展开更多
OBJECTIVE To study the function of neuronal nitric oxide synthase(nNOS) in the dentate gyrus(DG) in the pathology of epilepsy.METHODS The expression of nNOS in the DG was measured by qPCR and Western blotting in mice ...OBJECTIVE To study the function of neuronal nitric oxide synthase(nNOS) in the dentate gyrus(DG) in the pathology of epilepsy.METHODS The expression of nNOS in the DG was measured by qPCR and Western blotting in mice 3 and 12 h,1,7,14,and 60 d after treatment with pilocarpine(280 mg·kg-1,ip,one time).We constructed a type of lentiovirus encoding the full length cDNA of nNOS(LV-nNOS-GFP) and injected it and LV-GFP(1 μL) into the DG of the hippocampus 7 d after pilocarpine-induced seizure.The occurrence of epileptic spikes and spontaneous seizure(SRS)were monitored through electroencephalo-graph(EEG) and the protein expression was confirmed by Western blotting.We also constructed a lentioviral vehicle to interfere the expression of nNOS mRNA,which was named as LV-n NOSRNAi-GFP.A volume of 1 μL of LV-nNOS-RNAiGFP or LV-GFP was injected into the DG of the hippocampus 7 d before pilocarpine-induced seizure followed by EEG record and protein detection 2 months later.By EEG,we compared the susceptibility of nNOS knockout and wild-type mice to seizure induction and the development of epilepsy.In addition,we measured the influence of nNOS knockout on the excitability of dentate cells including mEPSC and mIPSC by using patch clamp technique.RESULTS Western blotting and qPCR measurement showed that the mRNA and protein expression of nNOS in the DG was not significantly changed in pilocarpinetreated mice compared with control mice.But the both m RNA and protein expression of nNOS decreased 7,14 and 60 d after treatment with pilocarpine(280 mg·kg-1,ip,one time).With infection of LV-nNOS-GFP in the DG,the decreased level of nNOS was recovered 7 d after seizure induction and the frequency of epileptic spikes and SRS were reversed by nNOS overexpression.We found that nNOS knockout caused a higher susceptive level to seizure induction by pilocarpine.Re-expression of nNOS in the DG of nNOS knockout mice relived the severity of epilepsy.By patch clamp recording,we found that there was no significant difference in the amplitude of mEPSC and mIPSC between nNOS knockout and wild-type mice,but the frequency of mEPSC was increased in nN OS knockout mice.Consistently,knockdown of nNOS by injection of LV-nNOS-RNAi-GFP into the DG caused higher frequency of epileptic spikes and SRS 2 months after pilocarpine-induced seizure.CONCLUSION Neurons expressing nNOS in the DG play an important role in the development of epilepsy.展开更多
In depth study of NO reveals that NO is a bioactive molecule that exerts a number of roles in many physiological and pathological process.NO is produced in response to drought,salinity,temperature shock and pathogen a...In depth study of NO reveals that NO is a bioactive molecule that exerts a number of roles in many physiological and pathological process.NO is produced in response to drought,salinity,temperature shock and pathogen attack.NO rapidly reacts with ROS,ABA and other hormones and directly or indirectly regulate ethylene biosynthesis.The authors review the response of between plant NO and kinds of stresses,and possible mechanism was discussed.展开更多
The tumor angiogenesis process is believed to be dependent on an "angiogenic switch" formed by a cascade of biologic events as a consequence of the "cross-talk" between tumor cells and several comp...The tumor angiogenesis process is believed to be dependent on an "angiogenic switch" formed by a cascade of biologic events as a consequence of the "cross-talk" between tumor cells and several components of local microenvironment including endothelial cells, macrophages, mast cells and stromal components. Oxidative stress represents an important stimulus that widely contributes to this angiogenic switch, which is particularly relevant in lungs, where oxidative stress is originated from different sources including the incomplete reduction of oxygen during respiration, exposure to hypoxia/reoxygenation, stimulated resident or chemoattracted immune cells to lung tissues, as well as by a variety of chemicals compounds. In the present review we highlight the role of oxidative stress in tumor angiogenesis as a key signal linked to other relevant actors in this complex process.展开更多
基金supported by the Guangxi Natural Science Fund for Distinguished Young Scholars(2024GXNSFFA010008)Shenzhen Science and Technology Program(JCYJ20230807112503008).
文摘Nitric oxide(NO),which generally originates from vehicle exhaust and industrial flue gases,is one of the most serious air pollutants.In this case,the electrochemical NO reduction reaction(NORR)not only removes the atmospheric pollutant NO but also produces valuable ammonia(NH_(3)).Hence,through the synthesis and modification of Fe_(3)C nanocrystal cata-lysts,the as-obtained optimal sample of Fe_(3)C/C-900 was adopted as the NORR catalyst at ambient conditions.As a result,the Fe_(3)C/C-900 catalyst showed an NH_(3)Faraday efficiency of 76.5%and an NH_(3)yield rate of 177.5μmol·h^(-1)·cm^(-2)at the working potentials of-0.8 and-1.2 V versus reversible hydrogen electrode(vs.RHE),respectively.And it delivered a stable NORR activity during the electrolysis.Moreover,we attribute the high NORR properties of Fe_(3)C/C-900 to two aspects:one is the enhanced intrinsic activity of Fe_(3)C nanocrystals,including the lowering of the energy barrier of rate-limiting step(*NOH→*N)and the inhibition of hydrogen evolution;on the other hand,the favorable dispersion of active components,the effective adsorption of gaseous NO,and the release of liquid NH_(3)products facilitated by the porous carbon substrate.
基金Project(2011CB201505)supported by the National Key Basic Research Program of ChinaProject(BA2011031)supported by the Special Fund of Transformation of Scientific and Technological Achievements of Jiangsu Province,China
文摘Nitric oxide(NO) from flue gas is hard to remove because of low solubility and reactivity. A new technology for photocatalytic oxidation of NO using ultraviolet(UV)/TiO2/H2O2 process is studied in an efficient laboratory-scale reactor. Effects of several key operational parameters on NO removal efficiency are studied, including TiO2 content, H2O2 initial concentration, UV lamp power, NO initial content, oxygen volume fraction and TiO2/H2O2 solution volume. The results illustrate that the NO removal efficiency increases with the increasing of H2O2 initial concentration or UV lamp power. Meanwhile, a lower NO initial content or a higher TiO2/H2O2 solution volume will result in higher NO removal efficiency. In addition, oxygen volume fraction has a little effect.The highest NO removal efficiency is achieved at the TiO2 content of 0.75 g/L, H2O2 initial concentration of 2.5 mol/L, UV lamp power of 36 W, NO initial content of 206×10-6 and TiO2/H2O2 solution volume of 600 m L. It is beneficial for the development and application of NO removal from coal-fired flue gas with UV/TiO2/H2O2 process.
基金the fund support from National Natural Science Foundation(30600432)Anhui Distinguished Youth Science and Technology Foundation (06041081)
文摘In order to investigate the effects of nitric oxide(NO) on the growth and development of porcine preantral follicles,we treated the follicles with different concentrations of sodium nitroprusside(SNP,0, 0.001,0.01,0.1 and 1 mmol/L),a NO donor.The results showed that the follicle diameter increased during in vitro culture,but there were no significant differences between the treatments(P】0.05);the survival rate in the 1 mmol/L SNP group was significantly lower than that in the 1μmol/L SNP group(61.61% vs 81.52%,P【0.05),but no significant differences were found between other treatments(P】0.05);the rate of antrum formation in the 1μmol/L SNP group peaked at 50%on day 4,and the rate in the 1μmol/L SNP group on day 6 was higher than that in the 0.01 mmol/L SNP group;in addition,the rate of antrum formation in the 1μmol/L SNP group was significantly higher than that in the 0.1 and 1 mmol/L SNP groups (Day 6:73.07%vs 50%,47.62%,P【0.05).After 6 days of culture,the proportion of normal oocytes in the1 mmol/L SNP group was significantly lower than that in the 1μmol/L SNP group(71.21%vs 48.18%, P【0.05),with no significant differences between other treatments(P】0.05).The recovery rate of cumulus cells oocyte complexes(COCs) in the 1μmol/L SNP group was significantly higher than that in the controls and all other treatments(37.27%vs 22.88%,25.59%,20.74%and 19.39%,P【0.05).The results indicate that during the in vitro culture of porcine preantral follicles,low concentration of NO released from SNP improves growth and development of oocytes and follicular antrum formation while high levels of NO are toxic to follicular survival.
基金Supported by Funding(RCB22)from the Doctoral Research Foundation of Northeast Agricultural University(2012)the Postdoctoral Fund of Heilongjiang Province(LBH-Z11239)
文摘Subclinical endometritis is a physiological inflammation that serves to clear persistent contaminants from the uterus. To investigate the alteration of antioxidant, such as vitamin E（VE） and vitamin C（VC）, total oxidant capacity（TOC） and nitric oxide（NO） in cows with normal and subclinical endometritis（SCE）, we examined the concentrations of NO, VC and VE, TOC and polymorphonuclear neutrophils（PMN） percentage in uterine secretion. The cows were divided into two groups, normal（n=20） and subclinical endometritis（SCE, n=60）, based on endometrial cytology（presence of PMN≥5%）. Uterine secretion and blood were collected as described previously. Griess reaction was used to determine the concentration of NO. The concentrations of TOC, VC and VE were detected by a commercially available assay kit. The results showed that the concentrations of NO, TOC and PMN percentage were significantly higher（P〈0.01, P〈0.05, and P〈0.01, respectively） in uterine secretion with SCE compared to those from normal; however, the levels of VC and VE were significantly lesser（P〈0.01）. In conclusion, the concentrations of NO, TOC, VC, VE and PMN percentage differed between normal and SCE cows. Meanwhile, the relationship between the concentration of NO and PMN percentage from uterine secretion in cows with subclinical endometritis were positively correlated. Consequently, these alterations in NO, TOC, VC, VE levels and PMN percentage contributed to as a diagnostic index of the uterine inflammation, with the aim to increase the reproduction of the cows and the decrease economic losses.
基金supported by National Natural Science Foundation of China(81502627)the Young Backbone Teachers Assistance Scheme of Henan Province Colleges and Universities(2016GGJS-065)
文摘OBJECTIVE To investigate the regulation of {O^2(2,4-dinitrophenyl)1-[(4-ethoxycarbonyl)piperazin-1-yl]diazen-1-ium-1,2-diolate}(JS-K),anitric oxide donor,on tumor energy metabolism in H22 tumor-bearing mice.METHODS The hepatoma animal model in BALB/c mice was established with H22 cell line.The JS-K group and model group were received JS-K(0.75 and 1.5 mg?kg^(-1)) and saline via tail intravenous once every 3 d for 14 d,received 5 injections,respectively.The positive group was received 5-FU 20 mg·kg^(-1) by intraperitoneal injection once a day for 14 d.On the 15 th day mice were sacrificed.The tumor growth inhibition rate were calculated.The activities of hexokinase(HK),phosphofructo kinase(PFK),pyruvate kinase(PK),succinate dehydrogenase(SDH),adenosine triphosphatase(ATPase),and the levels of lactic acid(LD) and adenosine triphosphate(ATP) in tumor tissues were determined by colorimetric method.RESULTS Compared with model group,the tumor mass of JS-K0.75 and 1.5 mg·kg^(-1) group was significantly reduced(P<0.01),and the tumor growth inhibition rate was 23.9% and 50.3%,respectively.The activity of HK,PFK,PK,SDH and ATPase of tumor tissue in model group was(22.6±3.7,14.4±2.6,12.9±3.2 and 10.5±2.6)U·g^(-1) protein and(0.70±0.10)μmol Pi·mg^(-1) protein per hour,respectively;which in JS-K 1.5 mg?kg^(-1) group was dropped by 42.0%,26.6%,22.7%,23.3% and 21.7%(P<0.01,P<0.05).Compared with the model group,the level of ATP and LD in JS-K group was dropped(P<0.01).CONCLUSION JS-K can inhibit the growth of tumor in H22 tumor-bearing mice and its mechanism may be related to regulating the tumor energy metabolism with inhibition of glycolysis and aerobic oxidation.
基金National Natural Science Foundation of China(81571269)Science Technology Innovation Fund of Nanjing Medical University (2017NJMUCX008).
文摘OBJECTIVE To study the function of neuronal nitric oxide synthase(nNOS) in the dentate gyrus(DG) in the pathology of epilepsy.METHODS The expression of nNOS in the DG was measured by qPCR and Western blotting in mice 3 and 12 h,1,7,14,and 60 d after treatment with pilocarpine(280 mg·kg-1,ip,one time).We constructed a type of lentiovirus encoding the full length cDNA of nNOS(LV-nNOS-GFP) and injected it and LV-GFP(1 μL) into the DG of the hippocampus 7 d after pilocarpine-induced seizure.The occurrence of epileptic spikes and spontaneous seizure(SRS)were monitored through electroencephalo-graph(EEG) and the protein expression was confirmed by Western blotting.We also constructed a lentioviral vehicle to interfere the expression of nNOS mRNA,which was named as LV-n NOSRNAi-GFP.A volume of 1 μL of LV-nNOS-RNAiGFP or LV-GFP was injected into the DG of the hippocampus 7 d before pilocarpine-induced seizure followed by EEG record and protein detection 2 months later.By EEG,we compared the susceptibility of nNOS knockout and wild-type mice to seizure induction and the development of epilepsy.In addition,we measured the influence of nNOS knockout on the excitability of dentate cells including mEPSC and mIPSC by using patch clamp technique.RESULTS Western blotting and qPCR measurement showed that the mRNA and protein expression of nNOS in the DG was not significantly changed in pilocarpinetreated mice compared with control mice.But the both m RNA and protein expression of nNOS decreased 7,14 and 60 d after treatment with pilocarpine(280 mg·kg-1,ip,one time).With infection of LV-nNOS-GFP in the DG,the decreased level of nNOS was recovered 7 d after seizure induction and the frequency of epileptic spikes and SRS were reversed by nNOS overexpression.We found that nNOS knockout caused a higher susceptive level to seizure induction by pilocarpine.Re-expression of nNOS in the DG of nNOS knockout mice relived the severity of epilepsy.By patch clamp recording,we found that there was no significant difference in the amplitude of mEPSC and mIPSC between nNOS knockout and wild-type mice,but the frequency of mEPSC was increased in nN OS knockout mice.Consistently,knockdown of nNOS by injection of LV-nNOS-RNAi-GFP into the DG caused higher frequency of epileptic spikes and SRS 2 months after pilocarpine-induced seizure.CONCLUSION Neurons expressing nNOS in the DG play an important role in the development of epilepsy.
文摘In depth study of NO reveals that NO is a bioactive molecule that exerts a number of roles in many physiological and pathological process.NO is produced in response to drought,salinity,temperature shock and pathogen attack.NO rapidly reacts with ROS,ABA and other hormones and directly or indirectly regulate ethylene biosynthesis.The authors review the response of between plant NO and kinds of stresses,and possible mechanism was discussed.
文摘The tumor angiogenesis process is believed to be dependent on an "angiogenic switch" formed by a cascade of biologic events as a consequence of the "cross-talk" between tumor cells and several components of local microenvironment including endothelial cells, macrophages, mast cells and stromal components. Oxidative stress represents an important stimulus that widely contributes to this angiogenic switch, which is particularly relevant in lungs, where oxidative stress is originated from different sources including the incomplete reduction of oxygen during respiration, exposure to hypoxia/reoxygenation, stimulated resident or chemoattracted immune cells to lung tissues, as well as by a variety of chemicals compounds. In the present review we highlight the role of oxidative stress in tumor angiogenesis as a key signal linked to other relevant actors in this complex process.
