Puerarin suppresses autophagy to alleviate cerebral ischemia/reperfusion injury, and accumulating evidence indicates that the AMPKm TOR signaling pathway regulates the activation of the autophagy pathway through the c...Puerarin suppresses autophagy to alleviate cerebral ischemia/reperfusion injury, and accumulating evidence indicates that the AMPKm TOR signaling pathway regulates the activation of the autophagy pathway through the coordinated phosphorylation of ULK1. In this study, we investigated the mechanisms underlying the neuroprotective effect of puerarin and its role in modulating autophagy via the AMPK-m TOR-ULK1 signaling pathway in the rat middle cerebral artery occlusion model of cerebral ischemia/reperfusion injury. Rats were intraperitoneally injected with puerarin, 50 or 100 mg/kg, daily for 7 days. Then, 30 minutes after the final administration, rats were subjected to transient middle cerebral artery occlusion for 90 minutes. Then, after 24 hours of reperfusion, the Longa score and infarct volume were evaluated in each group. Autophagosome formation was observed by transmission electron microscopy. LC3, Beclin-1 p62, AMPK, m TOR and ULK1 protein expression levels were examined by immunofluorescence and western blot assay. Puerarin substantially reduced the Longa score and infarct volume, and it lessened autophagosome formation in the hippocampal CA1 area following cerebral ischemia/reperfusion injury in a dose-dependent manner. Pretreatment with puerarin（50 or 100 mg/kg） reduced Beclin-1 expression and the LC3-II/LC3-I ratio, as well as p-AMPK and p S317-ULK1 levels. In comparison, it increased p62 expression. Furthermore, puerarin at 100 mg/kg dramatically increased the levels of p-m TOR and p S757-ULK1 in the hippocampus on the ischemic side. Our findings suggest that puerarin alleviates autophagy by activating the APMK-m TOR-ULK1 signaling pathway. Thus, puerarin might have therapeutic potential for treating cerebral ischemia/reperfusion injury.展开更多
BACKGROUND Hepatocellular carcinoma(HCC)is the world’s sixth most common malignant tumor and the third cause of cancer death.Although great progress has been made in hepatectomy,it is still associated with a certain ...BACKGROUND Hepatocellular carcinoma(HCC)is the world’s sixth most common malignant tumor and the third cause of cancer death.Although great progress has been made in hepatectomy,it is still associated with a certain degree of risk of posthepatectomy liver failure(PHLF),which extends the length of hospital stay and remains the leading cause of postoperative death.Studies have shown that assessment of hepatic functional reserve before hepatectomy is beneficial for reducing the incidence of PHLF.AIM To assess the value of model for end-stage liver disease(MELD)score combined with standardized future liver remnant(sFLR)volume in predicting PHLF in patients undergoing hepatectomy for HCC.METHODS This study was attended by 238 patients with HCC who underwent hepatectomy between January 2015 and January 2018.Discrimination of sFLR volume,MELD score,and sFLR/MELD ratio to predict PHLF was evaluated according to the area under the receiver operating characteristic curve.RESULTS The patients were divided into two groups according to whether PHLF occurred after hepatectomy.The incidence of PHLF was 8.4%in our research.The incidence of PHLF increased with the decrease in sFLR volume and the increase in MELD score.Both sFLR volume and MELD score were considered independent predictive factors for PHLF.Moreover,the cut-off value of the sFLR/MELD score to predict PHLF was 0.078(P<0.001).This suggests that an sFLR/MELD≥0.078 indicates a higher incidence of PHLF than an sFLR/MELD<0.078.CONCLUSION MELD combined with sFLR is a reliable and effective PHLF predictor,which is superior to MELD score or sFLR volume alone.展开更多
In this study, the density of metastable He2* in an atmospheric-pressure plasma jet operating in helium with 0.001% nitrogen has been measured using an auxiliary measuring electrode technique.In the glow discharge mod...In this study, the density of metastable He2* in an atmospheric-pressure plasma jet operating in helium with 0.001% nitrogen has been measured using an auxiliary measuring electrode technique.In the glow discharge mode, waveforms from two grounding electrodes, including one main discharge electrode and one auxiliary electrode, are captured.The isolated current peak formed by Penning ionization in waveforms from the auxiliary measuring electrode is identified to calculate the density of metastable He2*.In our discharge environment, the helium metastable densities along the jet axis direction are between 2.26×1013 and 1.74×1013 cm-3,which is in good agreement with the results measured by other techniques.This measurement technique can be conveniently applied to the diagnosis of metastable He2* in an atmospheric-pressure plasma jet array.展开更多
A new five-dimensional fractional-order laser chaotic system(FOLCS)is constructed by incorporating complex variables and fractional calculus into a Lorentz-Haken-type laser system.Dynamical behavior of the system,circ...A new five-dimensional fractional-order laser chaotic system(FOLCS)is constructed by incorporating complex variables and fractional calculus into a Lorentz-Haken-type laser system.Dynamical behavior of the system,circuit realization and application in pseudorandom number generators are studied.Many types of multi-stable states are discovered in the system.Interestingly,there are two types of state transition phenomena in the system,one is the chaotic state degenerates to a periodical state,and the other is the intermittent chaotic oscillation.In addition,the complexity of the system when two parameters change simultaneously is measured by the spectral entropy algorithm.Moreover,a digital circuit is design and the chaotic oscillation behaviors of the system are verified on this circuit.Finally,a pseudo-random sequence generator is designed using the FOLCS,and the statistical characteristics of the generated pseudo-random sequence are tested with the NIST-800-22.This study enriches the research on the dynamics and applications of FOLCS.展开更多
Due to their excellent carrier mobility,high absorption coefficient and narrow bandgap,most 2D IVA metal chalcogenide semiconductors(GIVMCs,metal=Ge,Sn,Pb;chalcogen=S,Se)are regarded as promising candidates for realiz...Due to their excellent carrier mobility,high absorption coefficient and narrow bandgap,most 2D IVA metal chalcogenide semiconductors(GIVMCs,metal=Ge,Sn,Pb;chalcogen=S,Se)are regarded as promising candidates for realizing high-performance photodetectors.We synthesized high-quality two-dimensional(2D)tin sulfide(SnS)nanosheets using the physical vapor deposition(PVD)method and fabricated a 2D SnS visible-light photodetector.The photodetector exhibits a high photoresponsivity of 161 A·W-1 and possesses an external quantum efficiency of 4.45×10^(4)%,as well as a detectivity of 1.15×10^(9) Jones under 450 nm blue light illumination.Moreover,under poor illumination at optical densities down to 2 mW·cm^(-2),the responsivity of the device is higher than that at stronger optical densities.We suggest that a photogating effect in the 2D SnS photodetector is mainly responsible for its low-light responsivity.Defects and impurities in 2D SnS can trap carriers and form localized electric fields,which can delay the recombination process of electron-hole pairs,prolong carrier lifetimes,and thus improve the low-light responsivity.This work provides design strategies for detecting low levels of light using photodetectors made of 2D materials.展开更多
Objective: To study the effect of dexmedetomidine on monophasic action potential amplitude (MAPA) in myocardial ischemia-reperfusion and its correlation with myocardial injury. Methods: SD rats were selected as the ex...Objective: To study the effect of dexmedetomidine on monophasic action potential amplitude (MAPA) in myocardial ischemia-reperfusion and its correlation with myocardial injury. Methods: SD rats were selected as the experimental animals and randomly divided into control group, ischemia reperfusion group (I/R group) and dexmedetomidine group (Dex group);I/R group and Dex group were made into myocardial ischemia-reperfusion injury models, and Dex group were given exmedetomidine intervention;the MAPA of myocardial tunica intima layer, tunica media layer and tunica externa layer were measured in Langendorff perfusion system;myocardial tissue was collected to determine the contents of oxidative stress molecules and the expression of apoptosis genes. Results: The MAPA levels of myocardial tunica intima layer, tunica media layer and tunica externa layer as well as Klotho and SOD contents in myocardial tissue of I/R group were significantly lower than those of control group whereas CaMKII, NOX2, NOX4 and MDA contents as well as CaSR, USP14, JNK, Bax, Fas and Caspase-3 mRNA expression in myocardial tissue were significantly higher than those of control group;the MAPA levels of myocardial tunica intima layer, tunica media layer and tunica externa layer as well as Klotho and SOD contents in myocardial tissue of Dex group were significantly higher than those of I/R group whereas CaMKII, NOX2, NOX4 and MDA contents as well as CaSR, USP14, JNK, Bax, Fas and Caspase-3 mRNA expression in myocardial tissue were significantly lower than those of I/R group;Pearson test showed that the MAPA levels of myocardial tunica intima layer, tunica media layer and tunica externa layer were negatively correlated with CaMKII, NOX2, NOX4 and MDA contents as well as CaSR, USP14, JNK, Bax, Fas and Caspase-3 mRNA expression in myocardial tissue, and positively correlated with Klotho and SOD contents. Conclusion: Dexmedetomidine can increase the MAPA in myocardial ischemia-reperfusion process, and is closely related to the inhibition of oxidative stress response and apoptosis.展开更多
基金supported by the National Natural Science Foundation of China,No.81202625the Open Fund of Key Laboratory of Cardiovascular and Cerebrovascular Diseases Translational Medicine,China Three Gorges University,China,No.2016xnxg101
文摘Puerarin suppresses autophagy to alleviate cerebral ischemia/reperfusion injury, and accumulating evidence indicates that the AMPKm TOR signaling pathway regulates the activation of the autophagy pathway through the coordinated phosphorylation of ULK1. In this study, we investigated the mechanisms underlying the neuroprotective effect of puerarin and its role in modulating autophagy via the AMPK-m TOR-ULK1 signaling pathway in the rat middle cerebral artery occlusion model of cerebral ischemia/reperfusion injury. Rats were intraperitoneally injected with puerarin, 50 or 100 mg/kg, daily for 7 days. Then, 30 minutes after the final administration, rats were subjected to transient middle cerebral artery occlusion for 90 minutes. Then, after 24 hours of reperfusion, the Longa score and infarct volume were evaluated in each group. Autophagosome formation was observed by transmission electron microscopy. LC3, Beclin-1 p62, AMPK, m TOR and ULK1 protein expression levels were examined by immunofluorescence and western blot assay. Puerarin substantially reduced the Longa score and infarct volume, and it lessened autophagosome formation in the hippocampal CA1 area following cerebral ischemia/reperfusion injury in a dose-dependent manner. Pretreatment with puerarin（50 or 100 mg/kg） reduced Beclin-1 expression and the LC3-II/LC3-I ratio, as well as p-AMPK and p S317-ULK1 levels. In comparison, it increased p62 expression. Furthermore, puerarin at 100 mg/kg dramatically increased the levels of p-m TOR and p S757-ULK1 in the hippocampus on the ischemic side. Our findings suggest that puerarin alleviates autophagy by activating the APMK-m TOR-ULK1 signaling pathway. Thus, puerarin might have therapeutic potential for treating cerebral ischemia/reperfusion injury.
基金Supported by the National Natural Science Foundation of China,No.81970569,No.81773293,and No.31660266Natural Science Foundation of Hunan Province,No.2015JJ4083,No.2019JJ50874,and No.2018JJ3758
文摘BACKGROUND Hepatocellular carcinoma(HCC)is the world’s sixth most common malignant tumor and the third cause of cancer death.Although great progress has been made in hepatectomy,it is still associated with a certain degree of risk of posthepatectomy liver failure(PHLF),which extends the length of hospital stay and remains the leading cause of postoperative death.Studies have shown that assessment of hepatic functional reserve before hepatectomy is beneficial for reducing the incidence of PHLF.AIM To assess the value of model for end-stage liver disease(MELD)score combined with standardized future liver remnant(sFLR)volume in predicting PHLF in patients undergoing hepatectomy for HCC.METHODS This study was attended by 238 patients with HCC who underwent hepatectomy between January 2015 and January 2018.Discrimination of sFLR volume,MELD score,and sFLR/MELD ratio to predict PHLF was evaluated according to the area under the receiver operating characteristic curve.RESULTS The patients were divided into two groups according to whether PHLF occurred after hepatectomy.The incidence of PHLF was 8.4%in our research.The incidence of PHLF increased with the decrease in sFLR volume and the increase in MELD score.Both sFLR volume and MELD score were considered independent predictive factors for PHLF.Moreover,the cut-off value of the sFLR/MELD score to predict PHLF was 0.078(P<0.001).This suggests that an sFLR/MELD≥0.078 indicates a higher incidence of PHLF than an sFLR/MELD<0.078.CONCLUSION MELD combined with sFLR is a reliable and effective PHLF predictor,which is superior to MELD score or sFLR volume alone.
基金the State Scholarship Fund(No.201709480008)Hunan Province Education Scientific Project(No.19A164)National Undergraduate Research and Creative Experiment Project(No.S202010534006)。
基金supported by National Natural Science Foundation of China (No.11105093)
文摘In this study, the density of metastable He2* in an atmospheric-pressure plasma jet operating in helium with 0.001% nitrogen has been measured using an auxiliary measuring electrode technique.In the glow discharge mode, waveforms from two grounding electrodes, including one main discharge electrode and one auxiliary electrode, are captured.The isolated current peak formed by Penning ionization in waveforms from the auxiliary measuring electrode is identified to calculate the density of metastable He2*.In our discharge environment, the helium metastable densities along the jet axis direction are between 2.26×1013 and 1.74×1013 cm-3,which is in good agreement with the results measured by other techniques.This measurement technique can be conveniently applied to the diagnosis of metastable He2* in an atmospheric-pressure plasma jet array.
基金Project supported by the National Natural Science Foundation of China(Grant No.62061014)the Natural Science Foundation of Liaoning Province,China(Grant No.2020-MS-274)。
文摘A new five-dimensional fractional-order laser chaotic system(FOLCS)is constructed by incorporating complex variables and fractional calculus into a Lorentz-Haken-type laser system.Dynamical behavior of the system,circuit realization and application in pseudorandom number generators are studied.Many types of multi-stable states are discovered in the system.Interestingly,there are two types of state transition phenomena in the system,one is the chaotic state degenerates to a periodical state,and the other is the intermittent chaotic oscillation.In addition,the complexity of the system when two parameters change simultaneously is measured by the spectral entropy algorithm.Moreover,a digital circuit is design and the chaotic oscillation behaviors of the system are verified on this circuit.Finally,a pseudo-random sequence generator is designed using the FOLCS,and the statistical characteristics of the generated pseudo-random sequence are tested with the NIST-800-22.This study enriches the research on the dynamics and applications of FOLCS.
基金the National Natural Science Foundation of China(Grant Nos.1872251 and 11875229).
文摘Due to their excellent carrier mobility,high absorption coefficient and narrow bandgap,most 2D IVA metal chalcogenide semiconductors(GIVMCs,metal=Ge,Sn,Pb;chalcogen=S,Se)are regarded as promising candidates for realizing high-performance photodetectors.We synthesized high-quality two-dimensional(2D)tin sulfide(SnS)nanosheets using the physical vapor deposition(PVD)method and fabricated a 2D SnS visible-light photodetector.The photodetector exhibits a high photoresponsivity of 161 A·W-1 and possesses an external quantum efficiency of 4.45×10^(4)%,as well as a detectivity of 1.15×10^(9) Jones under 450 nm blue light illumination.Moreover,under poor illumination at optical densities down to 2 mW·cm^(-2),the responsivity of the device is higher than that at stronger optical densities.We suggest that a photogating effect in the 2D SnS photodetector is mainly responsible for its low-light responsivity.Defects and impurities in 2D SnS can trap carriers and form localized electric fields,which can delay the recombination process of electron-hole pairs,prolong carrier lifetimes,and thus improve the low-light responsivity.This work provides design strategies for detecting low levels of light using photodetectors made of 2D materials.
文摘Objective: To study the effect of dexmedetomidine on monophasic action potential amplitude (MAPA) in myocardial ischemia-reperfusion and its correlation with myocardial injury. Methods: SD rats were selected as the experimental animals and randomly divided into control group, ischemia reperfusion group (I/R group) and dexmedetomidine group (Dex group);I/R group and Dex group were made into myocardial ischemia-reperfusion injury models, and Dex group were given exmedetomidine intervention;the MAPA of myocardial tunica intima layer, tunica media layer and tunica externa layer were measured in Langendorff perfusion system;myocardial tissue was collected to determine the contents of oxidative stress molecules and the expression of apoptosis genes. Results: The MAPA levels of myocardial tunica intima layer, tunica media layer and tunica externa layer as well as Klotho and SOD contents in myocardial tissue of I/R group were significantly lower than those of control group whereas CaMKII, NOX2, NOX4 and MDA contents as well as CaSR, USP14, JNK, Bax, Fas and Caspase-3 mRNA expression in myocardial tissue were significantly higher than those of control group;the MAPA levels of myocardial tunica intima layer, tunica media layer and tunica externa layer as well as Klotho and SOD contents in myocardial tissue of Dex group were significantly higher than those of I/R group whereas CaMKII, NOX2, NOX4 and MDA contents as well as CaSR, USP14, JNK, Bax, Fas and Caspase-3 mRNA expression in myocardial tissue were significantly lower than those of I/R group;Pearson test showed that the MAPA levels of myocardial tunica intima layer, tunica media layer and tunica externa layer were negatively correlated with CaMKII, NOX2, NOX4 and MDA contents as well as CaSR, USP14, JNK, Bax, Fas and Caspase-3 mRNA expression in myocardial tissue, and positively correlated with Klotho and SOD contents. Conclusion: Dexmedetomidine can increase the MAPA in myocardial ischemia-reperfusion process, and is closely related to the inhibition of oxidative stress response and apoptosis.
