The antibacterial activity of copper is well-known from an ancient civilization, however, its biocidal mechanism has not been necessarily elucidated. Notwithstanding up to now, mainly 4 processes have been proposed. A...The antibacterial activity of copper is well-known from an ancient civilization, however, its biocidal mechanism has not been necessarily elucidated. Notwithstanding up to now, mainly 4 processes have been proposed. Among them, it is cleared that 4 kinds of reactive oxygen species (ROS): hydroxyl radical ·OH, hydrogen per oxide H<sub>2</sub>O<sub>2</sub>, superoxide anion ·O<sup>-</sup>2</sub></sub> and singlet oxygen <sup>1</sup>O<sub>2</sub>, play an important role for contact-killing of bacteria, viruses and fungi. In this paper, generation of ROS on the surfaces of copper plates heated from room temperature to 673 K for 4.2 × 10<sup>2</sup> s in air, was investigated using the chemiluminescence. ROS have been evaluated by selecting the most suitable scavengers, such as 2-propanol for ·OH, sodium pyruvate for H<sub>2</sub>O<sub>2</sub>, nitro blue tetrazolium for ·O<sup>-</sup>2</sub></sub>, and sodium azide NaN<sub>3</sub> for <sup>1</sup>O<sub>2</sub>. At the same time the outermost surface of copper, on which thin film of cuprous oxide Cu<sub>2</sub>O was first formed and then cupric oxide CuO was laminated on Cu<sub>2</sub>O, was examined by thin-film XRD and TEM analysis to estimate the amounts and kinds of copper oxides. It was found that the most amounts of ROS were obtained for the 573 K-heated Cu plate and they were composed of ·OH, H<sub>2</sub>O<sub>2</sub>, and ·O<sup>-</sup>2.</sub></sub>.展开更多
According to the characteristics of single-phase circuits and demand of using active filter for real-time detecting harmonic and reactive currents, a detecting method based on Fryze’s power definition is proposed. Th...According to the characteristics of single-phase circuits and demand of using active filter for real-time detecting harmonic and reactive currents, a detecting method based on Fryze’s power definition is proposed. The results of theoretical analysis and simulation show that the proposed method is effective in real-time detecting of instantaneous harmonic and reactive currents in single-phase circuits. When only detecting the total reactive currents, this method does not need a phase-locked loop circuit, and it also can be used in some special applications to provide different compensations on the ground of different requirements of electric network. Compared with the other methods based on the theory of instantaneous reactive power, this method is simple and easy to realize.展开更多
This paper reports that a series of silver oxide (Ag x O) films are deposited on glass substrates by direct-current reactive magnetron sputtering at a substrate temperature of 250 C and an oxygen flux ratio of 15:18 b...This paper reports that a series of silver oxide (Ag x O) films are deposited on glass substrates by direct-current reactive magnetron sputtering at a substrate temperature of 250 C and an oxygen flux ratio of 15:18 by modifying the sputtering power (SP).The Ag x O films deposited apparently show a structural evolution from cubic biphased (AgO + Ag 2 O) to cubic single-phased (Ag 2 O),and to biphased (Ag 2 O + AgO) structure.Notably,the cubic single-phased Ag 2 O film is deposited at the SP=105 W and an AgO phase with 220 orientation discerned in the Ag x O films deposited using the SP > 105 W.The transmissivity and reflectivity of the Ag x O films in transparent region decrease with the increase the SP,whereas the absorptivity inversely increases with the increase of the SP.These results may be due to the structural evolution and the increasing film thickness.A redshift of the films' absorption edges determined in terms of Tauc formula clearly occurs from 3.1 eV to 2.73 eV with the increase of the SP.展开更多
In this paper, an improved two-dimensional convolution neural network(2DCNN) is proposed to monitor and analyze elevator health, based on the distribution characteristics of elevator time series data in two-dimensiona...In this paper, an improved two-dimensional convolution neural network(2DCNN) is proposed to monitor and analyze elevator health, based on the distribution characteristics of elevator time series data in two-dimensional images. The current and effective power signals from an elevator traction machine are collected to generate gray-scale binary images. The improved two-dimensional convolution neural network is used to extract deep features from the images for classification, so as to recognize the elevator working conditions. Furthermore, the oscillation criterion is proposed to describe and analyze the active power oscillations. The current and active power are used to synchronously describe the working condition of the elevator, which can explain the co-occurrence state and potential relationship of elevator data. Based on the improved integration of local features of the time series, the recognition accuracy of the proposed 2DCNN is 97.78%, which is better than that of a one-dimensional convolution neural network. This research can improve the real-time monitoring and visual analysis performance of the elevator maintenance personnel, as well as improve their work efficiency.展开更多
Activated carbon was prepared from Enteromorpha prolifera by zinc chloride activation. The adsorption behaviors of three reactive dyes (Reactive Red 23, Reactive Blue 171 and Reactive Blue 4) onto this biomass activat...Activated carbon was prepared from Enteromorpha prolifera by zinc chloride activation. The adsorption behaviors of three reactive dyes (Reactive Red 23, Reactive Blue 171 and Reactive Blue 4) onto this biomass activated carbon were investigated in batch systems. The experimental findings showed that the removal efficiencies of three dyes onto activated carbon were maximum at the initial solution pH of 4.5 - 6.0. Thermodynamic studies suggested that adsorption reaction was an endothermic and spontaneous process. Adsorption isotherm of the three dyes obeyed Freundlich isotherm modal. Dye adsorption capacities of activated carbon were 59.88, 71.94 and 131.93 mg·g?1 for RR23, RB171 and RB4 at 27?C, respectively. Second-order kinetic models fitted better to the equilibrium data of three dyes. The adsorption process on activated carbon was mainly controlled by intraparticle diffusion mechanism.展开更多
BACKGROUND The Hippo signaling pathway regulates organ size by regulating cell proliferation and apoptosis with terminal effectors including Yes-associated protein-1(YAP-1).Dysregulation in Hippo pathway has been prop...BACKGROUND The Hippo signaling pathway regulates organ size by regulating cell proliferation and apoptosis with terminal effectors including Yes-associated protein-1(YAP-1).Dysregulation in Hippo pathway has been proposed as one of the therapeutic targets in hepatocarcinogenesis.The levels of reactive oxygen species(ROS)increase during the progression from early to advanced hepatocellular carcinoma(HCC).AIM To study the activation of YAP-1 by ROS-induced damage in HCC and the involved signaling pathway.METHODS The expression of YAP-1 in HCC cells(Huh-7,HepG2,and SNU-761)was quantified using real-time polymerase chain reaction and immunoblotting.Human HCC cells were treated with H2O2,which is a major component of ROS in living organisms,and with either YAP-1 small interfering RNA(siRNA)or control siRNA.To investigate the role of YAP-1 in HCC cells under oxidative stress,MTS assays were performed.Immunoblotting was performed to evaluate the signaling pathway responsible for the activation of YAP-1.Eighty-eight surgically resected frozen HCC tissue samples and 88 nontumor liver tissue samples were used for gene expression analyses.RESULTS H2O2 treatment increased the mRNA and protein expression of YAP-1 in HCC cells(Huh-7,HepG2,and SNU-761).Suppression of YAP-1 using siRNA transfection resulted in a significant decrease in tumor proliferation during H2O2 treatment both in vitro and in vivo(both P<0.05).The oncogenic action of YAP-1 occurred via the activation of the c-Myc pathway,leading to the upregulation of components of the unfolded protein response(UPR),including 78-kDa glucoseregulated protein and activating transcription factor-6(ATF-6).The YAP-1 mRNA levels in human HCC tissues were upregulated by 2.6-fold compared with those in nontumor tissues(P<0.05)and were positively correlated with the ATF-6 Levels(Pearson’s coefficient=0.299;P<0.05).CONCLUSION This study shows a novel connection between YAP-1 and the UPR through the c-Myc pathway during oxidative stress in HCC.The ROS-induced activation of YAP-1 via the c-Myc pathway,which leads to the activation of the UPR pathway,might be a therapeutic target in HCC.展开更多
Reactive oxygen species (ROS) are molecules or ions formed by the incomplete one-electron reduction of oxygen. Ofinterest, it seems that ROS manifest dual roles, cancer promoting or cancer suppressing, in tumorigenesi...Reactive oxygen species (ROS) are molecules or ions formed by the incomplete one-electron reduction of oxygen. Ofinterest, it seems that ROS manifest dual roles, cancer promoting or cancer suppressing, in tumorigenesis. ROS participate simultaneously in two signaling pathways that have inverse functions in tumorigenesis, Ras-Raf-MEK1/2-ERK1/2 signaling and the p38 mitogen-activated protein kinases (MAPK) pathway. It is well known that Ras-Raf-MEK1/2-ERK1/2 signaling is related to oncogenesis, while the p38 MAPK pathway contributes to cancer suppression, which involves oncogene-induced senescence, inflammationinduced cellular senescence, replicative senescence, contact inhibition and DNA-damage responses. Thus, ROS may not be an absolute carcinogenic factor or cancer suppressor. The purpose of the present review is to discuss the dual roles of ROS in the pathogenesis of cancer, and the signaling pathway mediating their role in tumorigenesis.展开更多
C-reactive protein(CRP) is a biomarker of inflammation.Increased plasma levels of CRP are associated with an increased risk of myocardial infarction.However,the correlation between plasma CRP concentration and atheros...C-reactive protein(CRP) is a biomarker of inflammation.Increased plasma levels of CRP are associated with an increased risk of myocardial infarction.However,the correlation between plasma CRP concentration and atherosclerotic plaque burden is poor.Based on these observations,it has been hypothesized that CRP increases the risk of myocardial infarction by promoting thrombosis.This article reviews available data that link enhanced CRP expression to increased risk of thrombosis,with a focus on the effects of CRP on hemostasis,platelet function,and fibrinolysis.Overall,the available data support the hypothesis that CRP is an important mechanistic link between inflammation and throm bosis.展开更多
A comparative study of treatment of simulated wastewater containing Reactive Red 195 using zero-valent iron/activated carbon(ZVI/AC),microwave discharge electrodeless lamp/sodium hypochlorite(MDEL/NaClO) and the combi...A comparative study of treatment of simulated wastewater containing Reactive Red 195 using zero-valent iron/activated carbon(ZVI/AC),microwave discharge electrodeless lamp/sodium hypochlorite(MDEL/NaClO) and the combination of ZVI/ACMDEL/NaClO was conducted.The preliminary results showed the two steps method of ZVI/AC-MDEL/NaClO had much higher degradation effciency than both single steps.The final color removal percentage was nearly up to 100% and the chemical oxygen demand reduction percentage was up to approximately 82%.The effects of operational parameters,including initial pH value of simulated wastewater,ZVI/AC ratio and particle size of ZVI were also investigated.In addition,from the discussion of synergistic effect between ZVI/AC and MEDL/NaClO,we found that in the ZVI/AC-MEDL/NaClO process,ZVI/AC could break the azo bond firstly and then MEDL/NaClO degraded the aromatic amine products effectively.Reversing the order would reduce the degradation effciency.展开更多
The effect of lanthanum (Ⅲ) on reactive oxygen metabolism of soybean seedlings under elevated ultraviolet-B radiation(UV-B:280~320 nm)at 0.15 and 0.45 W·cm-2 levels respectively was studied through hydroponics i...The effect of lanthanum (Ⅲ) on reactive oxygen metabolism of soybean seedlings under elevated ultraviolet-B radiation(UV-B:280~320 nm)at 0.15 and 0.45 W·cm-2 levels respectively was studied through hydroponics in the laboratory.Plasmolemma permeability and contents of malonadialdehyde(MDA),hydrogen peroxide(H2O2),and proline gradually increased during the imposition of UV-B radiation and subsequently decreased during recovery from UV-B stress.The dynamic tendency of catalase(CAT)activity was similar to that of the above four indices.The activity of peroxidase(POD)initially increased,then remained at a high level,and finally dropped steeply when soybean seedlings were exposed to a low dosage of UV-B radiation.However,POD activity rose throughout and declined slightly on the eleventh day when soybean seedlings were stressed by a high dosage.With the addition of La (Ⅲ) of 20 mg·L-1,the rising tendency of plasmolemma permeability and contents of MDA,H2O2,and proline were slowed down during the stress period,whereas the declining speed was accelerated during the recovery period.The activities of CAT and POD were higher than those without La (Ⅲ) in all experiments.It suggested that the regulative effect of La (Ⅲ) on antioxidant enzymes such as CAT and POD could strengthen their capacities to scavenge reactive oxygen species(ROS),decrease contents of MDA and proline,and maintain normal plasmolemma permeability.Further more,the protective potential of La (Ⅲ) was better under low UV-B radiation than under a high one.展开更多
Antioxidant properties elicited by plant species have a full range of perspective applications in human health care. In recent years, the prevention of cancer and cardiovascular diseases has been associated with the i...Antioxidant properties elicited by plant species have a full range of perspective applications in human health care. In recent years, the prevention of cancer and cardiovascular diseases has been associated with the ingestion of fresh fruits, vegetables or teas rich in natural antioxidants [1]. Extracts from the different part of the pomegranate plant such as juice, seed and peel have been reported to exhibit a potent antioxidant activity. But the anticarcinogenic activity of active principle from the pomegranate peel extract was not studied so far. Hence the present study was planned to explore the molecular mechanism of the anticarcinogenic activity pomegranate peel on A549 cell line. In this study, GC-MS analysis was carried out for the methanolic extract of pomegranate peel which revealed gallic acid (GA) as the major antioxidant compound in the extract. Hence GA was purified further through RP-HPLC and evaluated its anticancer potential by studying its effect on mitochondrial respiration, cell-membrane integrity, apoptotic body formation and the DNA fragmentation in cultured A549 cells. We observed increased level of reactive oxygen species in the cells treated with GA at the concentrations of 10 and 20 ug/ml. Further analysis of caspase activation (caspase 8 and 9) revealed activation of caspases 9 in the cells treated with GA at a concentration of 20 ug/ml. Thus the present study revealed that the GA isolated from the pomegranate peel extract (Kabul variety) induced apoptosis in A549 cells through intrinsic pathway.展开更多
A novel reactive resin as active support was synthesized by an improved method based on seed swelling and surface coating polymerization. The resin is monosized beads with inner nucleus of cross-linked polymer and sur...A novel reactive resin as active support was synthesized by an improved method based on seed swelling and surface coating polymerization. The resin is monosized beads with inner nucleus of cross-linked polymer and surface layer of copolymer containing epoxy groups. The physico-chemical structures of beads were characterized.展开更多
To determine the effect of tocilizumab (TCZ) on reactive oxygen species (ROS) in 11 patients with rheumatoid arthritis (RA), reactive oxygen metabolites (d-ROM) were measured using a Free Radical Elective Evaluator. T...To determine the effect of tocilizumab (TCZ) on reactive oxygen species (ROS) in 11 patients with rheumatoid arthritis (RA), reactive oxygen metabolites (d-ROM) were measured using a Free Radical Elective Evaluator. The Disease Activity Score (DAS28) and matrix metalloproteinase-3 (MMP-3) level were also evaluated. d-ROM measured 392 ± 110 Carratelli units [U. CARR] on initiation of TCZ, and significantly decreased to 237 ± 82, 248 ± 88, and 226 ± 91 U.CARR after 3, 6, and 12 months, respectively展开更多
The source reactive-current compensation is crucial in energy transmission efficiency. The compensator design in frequency-domain was already widely discussed and examined. This paper presents results of a study on ho...The source reactive-current compensation is crucial in energy transmission efficiency. The compensator design in frequency-domain was already widely discussed and examined. This paper presents results of a study on how to design reactive compensators in time-domain. It’s the first time the reactive compensator have been designed in time domain. The example of compensator design was presented.展开更多
The secondary bud burst can cause around 10%-20%yield losses in black currants,an economically important crop in parts of Europe,Asia and North America.The metabolism of reactive oxygen species(ROS)has been linked to ...The secondary bud burst can cause around 10%-20%yield losses in black currants,an economically important crop in parts of Europe,Asia and North America.The metabolism of reactive oxygen species(ROS)has been linked to bud dormancy and its early release(secondary bud burst)in several fruit crops.But the relationship between ROS metabolism and the secondary bud burst is still not well understood in black currants.In the present study,two black currant cultivars(Adelinia and Heifeng)with opposing tendency of exhibiting the secondary bud burst were sprayed with abscisic acid(ABA)and gibberellic acid(GA_(3))to either inhibit or induce the secondary bud burst.The results showed that ABA inhibited the secondary bud burst by reducing the contents of ROS(H_(2)O_(2),O_(2)-·)in buds;decreasing the activities of superoxide dismutase(SOD),peroxidase(POD)and catalase(CAT);and increasing the contents of oxidized glutathione(GSSG)and ascorbic acid(AsA).GA_(3) effectively induced the secondary bud burst by increasing ROS contents;increasing the activities of several antioxidant enzymes,such as SOD,POD,CAT,glutathione reductase(GR),ascorbate peroxidase(APX)and the contents of reduced glutathione(GSH);and decreasing the contents of AsA.The experimental results showed that GA_(3) treatment increased the content of ROS,accelerated the metabolism of reactive oxygen species,and promoted the second burst of black currants.However,ROS metabolism was at a low level under ABA treatment,and the buds remained dormant.These results suggested that ROS metabolism might play an important role in the two black currants of the secondary bud burst.展开更多
This paper first discusses the operating principle of instantaneous reactive power theory. Then, the theory is introduced into shunt active power filter and its control scheme is studied. Finally, Matlab/Simulink powe...This paper first discusses the operating principle of instantaneous reactive power theory. Then, the theory is introduced into shunt active power filter and its control scheme is studied. Finally, Matlab/Simulink power system toolbox is used to simulate the system. In the simulation model, as the most common harmonic source, 3-phase thyristor bridge rectifier circuit is constructed. The simulation results before and after the shunt active filter was switched to the system corresponding to different firing angles of the thyristors are presented and analyzed, which demonstrate the practicability and reliability of the proposed shunt active filter scheme.展开更多
A series of monochlorotriazine reactive antibacterial agents were synthesised by using 2,4,4’ - trichloro -2’ - hydroxydiphenyl ether as a starting material. The spectrum analyses (UV and MS) and elementary analy-se...A series of monochlorotriazine reactive antibacterial agents were synthesised by using 2,4,4’ - trichloro -2’ - hydroxydiphenyl ether as a starting material. The spectrum analyses (UV and MS) and elementary analy-ses were also carried out. These antibacterial agents can be used as the bacteria - resistance finishing agents of the cellulose fabrics. The treated fabrics possess excellent antibacterial activity and durable wash fastness. For ex-ample , the percentages of bacterial reduction of the fab-ric finished with reactive antibacterial agent 2RSDP are 98.5%, 98. 86% and 96.67% for Staphylococcus au-reus, Escherichia coli and Pseudomonas aeruginose re-spectively. After more than 100 times of washing at 60°C, the antibacterial activity still retains at a level of about 90% of the original. The relationships between the molecular structures of the reactive antibacterial finish-ing agents and their antibacterial activities are discussed.展开更多
文摘The antibacterial activity of copper is well-known from an ancient civilization, however, its biocidal mechanism has not been necessarily elucidated. Notwithstanding up to now, mainly 4 processes have been proposed. Among them, it is cleared that 4 kinds of reactive oxygen species (ROS): hydroxyl radical ·OH, hydrogen per oxide H<sub>2</sub>O<sub>2</sub>, superoxide anion ·O<sup>-</sup>2</sub></sub> and singlet oxygen <sup>1</sup>O<sub>2</sub>, play an important role for contact-killing of bacteria, viruses and fungi. In this paper, generation of ROS on the surfaces of copper plates heated from room temperature to 673 K for 4.2 × 10<sup>2</sup> s in air, was investigated using the chemiluminescence. ROS have been evaluated by selecting the most suitable scavengers, such as 2-propanol for ·OH, sodium pyruvate for H<sub>2</sub>O<sub>2</sub>, nitro blue tetrazolium for ·O<sup>-</sup>2</sub></sub>, and sodium azide NaN<sub>3</sub> for <sup>1</sup>O<sub>2</sub>. At the same time the outermost surface of copper, on which thin film of cuprous oxide Cu<sub>2</sub>O was first formed and then cupric oxide CuO was laminated on Cu<sub>2</sub>O, was examined by thin-film XRD and TEM analysis to estimate the amounts and kinds of copper oxides. It was found that the most amounts of ROS were obtained for the 573 K-heated Cu plate and they were composed of ·OH, H<sub>2</sub>O<sub>2</sub>, and ·O<sup>-</sup>2.</sub></sub>.
文摘According to the characteristics of single-phase circuits and demand of using active filter for real-time detecting harmonic and reactive currents, a detecting method based on Fryze’s power definition is proposed. The results of theoretical analysis and simulation show that the proposed method is effective in real-time detecting of instantaneous harmonic and reactive currents in single-phase circuits. When only detecting the total reactive currents, this method does not need a phase-locked loop circuit, and it also can be used in some special applications to provide different compensations on the ground of different requirements of electric network. Compared with the other methods based on the theory of instantaneous reactive power, this method is simple and easy to realize.
基金supported by the National Natural Science Foundation of China (Grant No. 60807001)the National Basic Research Program of China (Grant No. 2011CB201605)the Foundation of Henan Educational Committee (Grant No. 2010A140017)
文摘This paper reports that a series of silver oxide (Ag x O) films are deposited on glass substrates by direct-current reactive magnetron sputtering at a substrate temperature of 250 C and an oxygen flux ratio of 15:18 by modifying the sputtering power (SP).The Ag x O films deposited apparently show a structural evolution from cubic biphased (AgO + Ag 2 O) to cubic single-phased (Ag 2 O),and to biphased (Ag 2 O + AgO) structure.Notably,the cubic single-phased Ag 2 O film is deposited at the SP=105 W and an AgO phase with 220 orientation discerned in the Ag x O films deposited using the SP > 105 W.The transmissivity and reflectivity of the Ag x O films in transparent region decrease with the increase the SP,whereas the absorptivity inversely increases with the increase of the SP.These results may be due to the structural evolution and the increasing film thickness.A redshift of the films' absorption edges determined in terms of Tauc formula clearly occurs from 3.1 eV to 2.73 eV with the increase of the SP.
基金Sponsored by the National Natural Science Foundation of China (Grant No.61771223)the Key Research and Development Program of Jiangsu Province(Grant No.SBE2018334)。
文摘In this paper, an improved two-dimensional convolution neural network(2DCNN) is proposed to monitor and analyze elevator health, based on the distribution characteristics of elevator time series data in two-dimensional images. The current and effective power signals from an elevator traction machine are collected to generate gray-scale binary images. The improved two-dimensional convolution neural network is used to extract deep features from the images for classification, so as to recognize the elevator working conditions. Furthermore, the oscillation criterion is proposed to describe and analyze the active power oscillations. The current and active power are used to synchronously describe the working condition of the elevator, which can explain the co-occurrence state and potential relationship of elevator data. Based on the improved integration of local features of the time series, the recognition accuracy of the proposed 2DCNN is 97.78%, which is better than that of a one-dimensional convolution neural network. This research can improve the real-time monitoring and visual analysis performance of the elevator maintenance personnel, as well as improve their work efficiency.
文摘Activated carbon was prepared from Enteromorpha prolifera by zinc chloride activation. The adsorption behaviors of three reactive dyes (Reactive Red 23, Reactive Blue 171 and Reactive Blue 4) onto this biomass activated carbon were investigated in batch systems. The experimental findings showed that the removal efficiencies of three dyes onto activated carbon were maximum at the initial solution pH of 4.5 - 6.0. Thermodynamic studies suggested that adsorption reaction was an endothermic and spontaneous process. Adsorption isotherm of the three dyes obeyed Freundlich isotherm modal. Dye adsorption capacities of activated carbon were 59.88, 71.94 and 131.93 mg·g?1 for RR23, RB171 and RB4 at 27?C, respectively. Second-order kinetic models fitted better to the equilibrium data of three dyes. The adsorption process on activated carbon was mainly controlled by intraparticle diffusion mechanism.
文摘BACKGROUND The Hippo signaling pathway regulates organ size by regulating cell proliferation and apoptosis with terminal effectors including Yes-associated protein-1(YAP-1).Dysregulation in Hippo pathway has been proposed as one of the therapeutic targets in hepatocarcinogenesis.The levels of reactive oxygen species(ROS)increase during the progression from early to advanced hepatocellular carcinoma(HCC).AIM To study the activation of YAP-1 by ROS-induced damage in HCC and the involved signaling pathway.METHODS The expression of YAP-1 in HCC cells(Huh-7,HepG2,and SNU-761)was quantified using real-time polymerase chain reaction and immunoblotting.Human HCC cells were treated with H2O2,which is a major component of ROS in living organisms,and with either YAP-1 small interfering RNA(siRNA)or control siRNA.To investigate the role of YAP-1 in HCC cells under oxidative stress,MTS assays were performed.Immunoblotting was performed to evaluate the signaling pathway responsible for the activation of YAP-1.Eighty-eight surgically resected frozen HCC tissue samples and 88 nontumor liver tissue samples were used for gene expression analyses.RESULTS H2O2 treatment increased the mRNA and protein expression of YAP-1 in HCC cells(Huh-7,HepG2,and SNU-761).Suppression of YAP-1 using siRNA transfection resulted in a significant decrease in tumor proliferation during H2O2 treatment both in vitro and in vivo(both P<0.05).The oncogenic action of YAP-1 occurred via the activation of the c-Myc pathway,leading to the upregulation of components of the unfolded protein response(UPR),including 78-kDa glucoseregulated protein and activating transcription factor-6(ATF-6).The YAP-1 mRNA levels in human HCC tissues were upregulated by 2.6-fold compared with those in nontumor tissues(P<0.05)and were positively correlated with the ATF-6 Levels(Pearson’s coefficient=0.299;P<0.05).CONCLUSION This study shows a novel connection between YAP-1 and the UPR through the c-Myc pathway during oxidative stress in HCC.The ROS-induced activation of YAP-1 via the c-Myc pathway,which leads to the activation of the UPR pathway,might be a therapeutic target in HCC.
基金Supported by National Natural Science Foundation of China, No. 30750013 Key Science Research Project Natural Science Foundation of Xiamen, No. WKZ0501
文摘Reactive oxygen species (ROS) are molecules or ions formed by the incomplete one-electron reduction of oxygen. Ofinterest, it seems that ROS manifest dual roles, cancer promoting or cancer suppressing, in tumorigenesis. ROS participate simultaneously in two signaling pathways that have inverse functions in tumorigenesis, Ras-Raf-MEK1/2-ERK1/2 signaling and the p38 mitogen-activated protein kinases (MAPK) pathway. It is well known that Ras-Raf-MEK1/2-ERK1/2 signaling is related to oncogenesis, while the p38 MAPK pathway contributes to cancer suppression, which involves oncogene-induced senescence, inflammationinduced cellular senescence, replicative senescence, contact inhibition and DNA-damage responses. Thus, ROS may not be an absolute carcinogenic factor or cancer suppressor. The purpose of the present review is to discuss the dual roles of ROS in the pathogenesis of cancer, and the signaling pathway mediating their role in tumorigenesis.
基金Supported by Merit Review Award from the Department of Veterans Affairs,research grants from the Missouri Life Sciences Research Board and NIH,No. HL57346
文摘C-reactive protein(CRP) is a biomarker of inflammation.Increased plasma levels of CRP are associated with an increased risk of myocardial infarction.However,the correlation between plasma CRP concentration and atherosclerotic plaque burden is poor.Based on these observations,it has been hypothesized that CRP increases the risk of myocardial infarction by promoting thrombosis.This article reviews available data that link enhanced CRP expression to increased risk of thrombosis,with a focus on the effects of CRP on hemostasis,platelet function,and fibrinolysis.Overall,the available data support the hypothesis that CRP is an important mechanistic link between inflammation and throm bosis.
基金supported by the Major Projects on Control and Rectification of Water Body Pollution (Water Special Project) (No.2009ZX07010-001,2008ZX07526-001)the National Basic Research Program (973) of China (No.2008CB418201)
文摘A comparative study of treatment of simulated wastewater containing Reactive Red 195 using zero-valent iron/activated carbon(ZVI/AC),microwave discharge electrodeless lamp/sodium hypochlorite(MDEL/NaClO) and the combination of ZVI/ACMDEL/NaClO was conducted.The preliminary results showed the two steps method of ZVI/AC-MDEL/NaClO had much higher degradation effciency than both single steps.The final color removal percentage was nearly up to 100% and the chemical oxygen demand reduction percentage was up to approximately 82%.The effects of operational parameters,including initial pH value of simulated wastewater,ZVI/AC ratio and particle size of ZVI were also investigated.In addition,from the discussion of synergistic effect between ZVI/AC and MEDL/NaClO,we found that in the ZVI/AC-MEDL/NaClO process,ZVI/AC could break the azo bond firstly and then MEDL/NaClO degraded the aromatic amine products effectively.Reversing the order would reduce the degradation effciency.
基金Project supported by the National Natural Science Foundation of China(30570323)the Foundation of State Developingand Reforming Committee(IFZ20051210)
文摘The effect of lanthanum (Ⅲ) on reactive oxygen metabolism of soybean seedlings under elevated ultraviolet-B radiation(UV-B:280~320 nm)at 0.15 and 0.45 W·cm-2 levels respectively was studied through hydroponics in the laboratory.Plasmolemma permeability and contents of malonadialdehyde(MDA),hydrogen peroxide(H2O2),and proline gradually increased during the imposition of UV-B radiation and subsequently decreased during recovery from UV-B stress.The dynamic tendency of catalase(CAT)activity was similar to that of the above four indices.The activity of peroxidase(POD)initially increased,then remained at a high level,and finally dropped steeply when soybean seedlings were exposed to a low dosage of UV-B radiation.However,POD activity rose throughout and declined slightly on the eleventh day when soybean seedlings were stressed by a high dosage.With the addition of La (Ⅲ) of 20 mg·L-1,the rising tendency of plasmolemma permeability and contents of MDA,H2O2,and proline were slowed down during the stress period,whereas the declining speed was accelerated during the recovery period.The activities of CAT and POD were higher than those without La (Ⅲ) in all experiments.It suggested that the regulative effect of La (Ⅲ) on antioxidant enzymes such as CAT and POD could strengthen their capacities to scavenge reactive oxygen species(ROS),decrease contents of MDA and proline,and maintain normal plasmolemma permeability.Further more,the protective potential of La (Ⅲ) was better under low UV-B radiation than under a high one.
文摘Antioxidant properties elicited by plant species have a full range of perspective applications in human health care. In recent years, the prevention of cancer and cardiovascular diseases has been associated with the ingestion of fresh fruits, vegetables or teas rich in natural antioxidants [1]. Extracts from the different part of the pomegranate plant such as juice, seed and peel have been reported to exhibit a potent antioxidant activity. But the anticarcinogenic activity of active principle from the pomegranate peel extract was not studied so far. Hence the present study was planned to explore the molecular mechanism of the anticarcinogenic activity pomegranate peel on A549 cell line. In this study, GC-MS analysis was carried out for the methanolic extract of pomegranate peel which revealed gallic acid (GA) as the major antioxidant compound in the extract. Hence GA was purified further through RP-HPLC and evaluated its anticancer potential by studying its effect on mitochondrial respiration, cell-membrane integrity, apoptotic body formation and the DNA fragmentation in cultured A549 cells. We observed increased level of reactive oxygen species in the cells treated with GA at the concentrations of 10 and 20 ug/ml. Further analysis of caspase activation (caspase 8 and 9) revealed activation of caspases 9 in the cells treated with GA at a concentration of 20 ug/ml. Thus the present study revealed that the GA isolated from the pomegranate peel extract (Kabul variety) induced apoptosis in A549 cells through intrinsic pathway.
基金supported by the National Natural Science Foundation of China(Grant No.29635010).
文摘A novel reactive resin as active support was synthesized by an improved method based on seed swelling and surface coating polymerization. The resin is monosized beads with inner nucleus of cross-linked polymer and surface layer of copolymer containing epoxy groups. The physico-chemical structures of beads were characterized.
文摘To determine the effect of tocilizumab (TCZ) on reactive oxygen species (ROS) in 11 patients with rheumatoid arthritis (RA), reactive oxygen metabolites (d-ROM) were measured using a Free Radical Elective Evaluator. The Disease Activity Score (DAS28) and matrix metalloproteinase-3 (MMP-3) level were also evaluated. d-ROM measured 392 ± 110 Carratelli units [U. CARR] on initiation of TCZ, and significantly decreased to 237 ± 82, 248 ± 88, and 226 ± 91 U.CARR after 3, 6, and 12 months, respectively
文摘The source reactive-current compensation is crucial in energy transmission efficiency. The compensator design in frequency-domain was already widely discussed and examined. This paper presents results of a study on how to design reactive compensators in time-domain. It’s the first time the reactive compensator have been designed in time domain. The example of compensator design was presented.
基金Supported by Academic Backbone Project of Northeast Agricultural University(20XG04)the National Key R&D Program of China(2018YFD1000200)Heilongjiang Province Postdoctoral Startup Fund(LBH-Q17029)。
文摘The secondary bud burst can cause around 10%-20%yield losses in black currants,an economically important crop in parts of Europe,Asia and North America.The metabolism of reactive oxygen species(ROS)has been linked to bud dormancy and its early release(secondary bud burst)in several fruit crops.But the relationship between ROS metabolism and the secondary bud burst is still not well understood in black currants.In the present study,two black currant cultivars(Adelinia and Heifeng)with opposing tendency of exhibiting the secondary bud burst were sprayed with abscisic acid(ABA)and gibberellic acid(GA_(3))to either inhibit or induce the secondary bud burst.The results showed that ABA inhibited the secondary bud burst by reducing the contents of ROS(H_(2)O_(2),O_(2)-·)in buds;decreasing the activities of superoxide dismutase(SOD),peroxidase(POD)and catalase(CAT);and increasing the contents of oxidized glutathione(GSSG)and ascorbic acid(AsA).GA_(3) effectively induced the secondary bud burst by increasing ROS contents;increasing the activities of several antioxidant enzymes,such as SOD,POD,CAT,glutathione reductase(GR),ascorbate peroxidase(APX)and the contents of reduced glutathione(GSH);and decreasing the contents of AsA.The experimental results showed that GA_(3) treatment increased the content of ROS,accelerated the metabolism of reactive oxygen species,and promoted the second burst of black currants.However,ROS metabolism was at a low level under ABA treatment,and the buds remained dormant.These results suggested that ROS metabolism might play an important role in the two black currants of the secondary bud burst.
文摘This paper first discusses the operating principle of instantaneous reactive power theory. Then, the theory is introduced into shunt active power filter and its control scheme is studied. Finally, Matlab/Simulink power system toolbox is used to simulate the system. In the simulation model, as the most common harmonic source, 3-phase thyristor bridge rectifier circuit is constructed. The simulation results before and after the shunt active filter was switched to the system corresponding to different firing angles of the thyristors are presented and analyzed, which demonstrate the practicability and reliability of the proposed shunt active filter scheme.
基金Ph.D.Research Foundation of the Ministry of National Education
文摘A series of monochlorotriazine reactive antibacterial agents were synthesised by using 2,4,4’ - trichloro -2’ - hydroxydiphenyl ether as a starting material. The spectrum analyses (UV and MS) and elementary analy-ses were also carried out. These antibacterial agents can be used as the bacteria - resistance finishing agents of the cellulose fabrics. The treated fabrics possess excellent antibacterial activity and durable wash fastness. For ex-ample , the percentages of bacterial reduction of the fab-ric finished with reactive antibacterial agent 2RSDP are 98.5%, 98. 86% and 96.67% for Staphylococcus au-reus, Escherichia coli and Pseudomonas aeruginose re-spectively. After more than 100 times of washing at 60°C, the antibacterial activity still retains at a level of about 90% of the original. The relationships between the molecular structures of the reactive antibacterial finish-ing agents and their antibacterial activities are discussed.