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Melatonin Attenuates Mitochondrial Damage in Aristolochic Acid-Induced Acute Kidney Injury
Sun Jian,Pan Jinjin,Liu Qinlong,Cheng Jizhong,Tang Qing,Ji Yuke,Cheng Ke,wang Rui,Liu Liang,Wang Dingyou,Wu Na,Zheng Xu,Li Junxia,Zhang Xueyan,Zhu Zhilong,Ding Yanchun,Zheng Feng,Li Jia,Zhang Ying,Yua 한국응용약물학회 2023 Biomolecules & Therapeutics(구 응용약물학회지) Vol.31 No.1
Aristolochic acid (AA), extracted from Aristolochiaceae plants, plays an essential role in traditional herbal medicines and is used for different diseases. However, AA has been found to be nephrotoxic and is known to cause aristolochic acid nephropathy (AAN). AA-induced acute kidney injury (AKI) is a syndrome in AAN with a high morbidity that manifests mitochondrial damage as a key part of its pathological progression. Melatonin primarily serves as a mitochondria-targeted antioxidant. However, its mitochondrial protective role in AA-induced AKI is barely reported. In this study, mice were administrated 2.5 mg/kg AA to induce AKI. Melatonin reduced the increase in Upro and Scr and attenuated the necrosis and atrophy of renal proximal tubules in mice exposed to AA. Melatonin suppressed ROS generation, MDA levels and iNOS expression and increased SOD activities in vivo and in vitro. Intriguingly, the in vivo study revealed that melatonin decreased mitochondrial fragmentation in renal proximal tubular cells and increased ATP levels in kidney tissues in response to AA. In vitro, melatonin restored the mitochondrial membrane potential (MMP) in NRK-52E and HK-2 cells and led to an elevation in ATP levels. Confocal immunofluorescence data showed that puncta containing Mito-tracker and GFP-LC3A/B were reduced, thereby impeding the mitophagy of tubular epithelial cells. Furthermore, melatonin decreased LC3A/B-II expression and increased p62 expression. The apoptosis of tubular epithelial cells induced by AA was decreased. Therefore, our findings revealed that melatonin could prevent AA-induced AKI by attenuating mitochondrial damage, which may provide a potential therapeutic method for renal AA toxicity.
Jian Chen,Zheng Wang,Yibo Wang,Ming Cheng 전력전자학회 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.6
The purpose of this paper is to study a high-performance control scheme for neutral-point-clamping three-level (NPC-3L) inverter fed dual three-phase permanent magnet synchronous motor (PMSM) drives by considering some asymmetric factors such as the non-identical parameters in phase windings. To implement this, the system model is analyzed for dual three-phase PMSM drives with asymmetric factors based on the vector space decomposition (VSD) principle. Based on the equivalent circuits, PI controllers with feedforward compensation are used in the d-q subspace for regulating torque, where the cut-off frequency of the PI controllers are set at the twice the fundamental frequency for compensating both the additional DC component and the second order component caused by asymmetry. Meanwhile, proportional resonant (PR) controllers are proposed in the x-y subspace for suppressing the possible unbalanced currents in the phase windings. A dual three-phase space vector modulation (DT-SVM) is designed for the drive, and the balancing factor is designed based on the numerical fitting surface for balancing the DC link capacitor voltages. Experimental results are given to demonstrate the validity of the theoretical analysis and the proposed control scheme.
( Jian Shun Chen ),( Chun Fang ),( Ning Yu Zhu ),( Yong Hui Lv ),( Chang Yong Cheng ),( Yi Jiang Bei ),( Tianlun Zheng ),( Wei Huan Fang ) 한국미생물 · 생명공학회 2012 Journal of microbiology and biotechnology Vol.22 No.5
Listeria monocytogenes is an important foodborne pathogen that comprises four genetic lineages: I, II, III, and IV. Of these, lineage II is frequently recovered from foods and environments and responsible for the increasing incidence of human listeriosis. In this study, the phylogenetic structure of lineage II was determined through sequencing analysis of the ascB-dapE internalin cluster. Fifteen sequence types proposed by multilocus sequence typing based on nine housekeeping genes were grouped into three distinct sublineages, IIA, IIB, and IIC. Organization of the ascBdapE internalin cluster could serve as a molecular marker for these sublineages, with inlGHE, inlGC2DE, and inlC2DE for IIA, IIB, and IIC, respectively. These sublineages displayed specific genetic and phenotypic characteristics. IIA and IIC showed a higher frequency of recombination (ρ/θ). However, recombination events had greater effect (r/m) on IIB, leading to its high nucleotide diversity. Moreover, IIA and IIB harbored a wider range of internalin and stress-response genes, and possessed higher nisin tolerance, whereas IIC contained the largest portion of low-virulent strains owing to premature stop codons in inlA. The results of this study indicate that IIA, IIB, and IIC might occupy different ecological niches, and IIB might have a better adaptation to a broad range of environmental niches.
ULTRAFINE AU NANODOTS ON GRAPHENE OXIDE FOR CATALYTIC REDUCTION OF 4-NITROPHENOL
JIANLI CHEN,GANG CHENG,ZHUANGNAN LI,FUJUN MIAO,XIAOQIANG CUI,WEITAO ZHENG 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2013 NANO Vol.8 No.3
Graphene oxide nanosheet is an ideal platform to capture nanoparticles for highly efficient catalysis, electrochemical sensing and biosensing. In this work, we have described a simple synthesis method for preparation graphene oxide–Au nanohybrid. Au nanodots with an average size of 1.6 nm uniformly dispersed on the surface of graphene oxide. The well-defined nanostructure has been characterized by transmission electron microscopy (TEM) and atomic force microscopy (AFM). The nanohybrid also exhibits enhanced catalytic activity toward the reduction of 4-nitrophenol by NaBH4. Comparing with pure Au nanodots and graphene oxide, graphene oxide–Au nanohybrid shows the highest catalytic activity. This approach not only suggests a wide potential application of graphene oxide nanosheet as a host material for supporting a variety of nanoparticles, but also provides a new approach for the fabrication of graphene-based nanohybrids with multiple physical and chemical properties.
6`-O-Galloylpaeoniflorin Protects Human Keratinocytes Against Oxidative Stress-Induced Cell Damage
( Cheng Wen Yao ),( Mei Jing Piao ),( Ki Cheon Kim ),( Jian Zheng ),( Ji Won Cha ),( Jin Won Hyun ) 한국응용약물학회 2013 Biomolecules & Therapeutics(구 응용약물학회지) Vol.21 No.5
6`-O-galloylpaeonifl orin (GPF) is a galloylated derivate of paeonifl orin and a key chemical constituent of the peony root, a perennial fl owering plant that is widely used as an herbal medicine in East Asia. This study is the fi rst investigation of the cytoprotective effects of GPF against hydrogen peroxide (H2O2)-induced cell injury and death in human HaCaT keratinocytes. GPF demonstrated a signifi cant scavenging capacity against the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical, H2O2-generated intracellular reactive oxygen species (ROS), the superoxide anion radical (O2 -), and the hydroxyl radical (?OH). GPF also safeguarded HaCaT keratinocytes against H2O2-provoked apoptotic cell death and attenuated oxidative macromolecular damage to DNA, lipids, and proteins. The compound exerted its cytoprotective actions in keratinocytes at least in part by decreasing the number of DNA strand breaks, the levels of 8-isoprostane (a stable end-product of lipid peroxidation), and the formation of carbonylated protein species. Taken together, these results indicate that GPF may be developed as a cytoprotector against ROS-mediated oxidative stress.
Jian-hua Deng,Zhao-xia Ping,Rui-ting Zheng,Guo-an Cheng 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.58 No.41
The stability behaviors of multiwalled carbon nanotube arrays during field electron emission are studied. The results indicate that the stability, even at a high emission current density, has been greatly improved by an aging process, and a degradation of about 0.66% in the emission current density at 21.86 mA/cm_2 during a 10-hour stability test has been obtained. A detailed analysis of the deterioration of the field electron emission characteristics is given, and the generation of Joule heat during field emission is found to be able to burn off the extruded carbon nanotubes, which will directly reduce the number of emission sites. On the other hand, the Joule heating effect may induce an annealing of the defects existing in the carbon nanotubes and may influence the distribution of electron energy states, both having a bad influence on the field emission characteristics. An aging process, especially aging at high emission current densities, can greatly reduce the influence of Jouleheating induced current degradation. Hence, an aging process at high emission current densities provides an effective way to realize long-term stable field electron emission from carbon nanotube arrays.
Anti-Oxidation of Cultured Cordyceps militaris Growing on Silkworm Pupa
Gong Cheng-Liang,Pan Zhong-Hua,Zheng Xiao-Jian,Xue Ren-Yu,Cao Guang Li Korean Society of Sericultural Science 2006 International Journal of Industrial Entomology Vol.12 No.1
Cordyceps, one of the well-known traditional Chinese medicines, consists of the dried fungus C. sinensis growing on the larva of caterpillar. It is commonly used as a tonic of restoring vital body functions. In order to evaluate the pharmacological effects of C. militaris, the anti-oxidation and antiaging effect of cultured C. militaris growing on pupa of silkworm Bombyx mori, were investigated. The results showed! that the contents of lipofusin in myocardium were reduced and the SOD activity in the liver were elevated in a dose-dependent manner while no effect was observed for blood GSH-Px activity and liver MDA content in mice perfused with the cultured C. militaris compared to those untreated mice. Furthermore, the average life span, maximum life span and 50% death time of the fruit flies treated with cultured C. militaris were markedly prolonged. The results suggest that the cultured C. militaris growing on pupa of silkworm possesses anti-oxidation and delay senescence activity.
Chen, Jian,Wang, Zheng,Wang, Yibo,Cheng, Ming The Korean Institute of Power Electronics 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.6
The purpose of this paper is to study a high-performance control scheme for neutral-point-clamping three-level (NPC-3L) inverter fed dual three-phase permanent magnet synchronous motor (PMSM) drives by considering some asymmetric factors such as the non-identical parameters in phase windings. To implement this, the system model is analyzed for dual three-phase PMSM drives with asymmetric factors based on the vector space decomposition (VSD) principle. Based on the equivalent circuits, PI controllers with feedforward compensation are used in the d-q subspace for regulating torque, where the cut-off frequency of the PI controllers are set at the twice the fundamental frequency for compensating both the additional DC component and the second order component caused by asymmetry. Meanwhile, proportional resonant (PR) controllers are proposed in the x-y subspace for suppressing the possible unbalanced currents in the phase windings. A dual three-phase space vector modulation (DT-SVM) is designed for the drive, and the balancing factor is designed based on the numerical fitting surface for balancing the DC link capacitor voltages. Experimental results are given to demonstrate the validity of the theoretical analysis and the proposed control scheme.
Jun Cheng,Jian‑hua Zhao,Dengzhi Zheng,Ke He,Yu Guo 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.3
The galvanized-Q235/AZ91D bimetallic material was achieved via solid–liquid compound casting, and the effect of theheat treatment at 250 °C for 3 h on the microstructure and mechanical properties of the galvanized-Q235/AZ91D bimetallicmaterial were investigated. The interface zone in the galvanized-Q235/AZ91D was composed of three different layers whichwere the FeAl3+ α-Mg, (α-Mg + MgZn), and α-Mg + (α-Mg + MgZn) from the galvanized-Q235 to AZ91D, successively. After the heat treatment, the (α-Mg + MgZn) eutectic structure was transformed into Al5Mg11Zn4to promote the microhardnessfrom 139.2 HV to reach 298.8 HV. In addition, the α-Mg and (α-Mg + Mg12Al17) eutectic structure in AZ91D wereseparately transformed into (α-Mg + Al5Mg11Zn4) and Al5Mg11Zn4resulting in the increasement of microhardness, from59.5 to 173.4 HV and 294.2 HV, respectively. Moreover, the interfacial shear strength was changed from 11.23 to 24.63 MPadue to the formation of Al5Mg11Zn4and the vanishment of MgZn.