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Chemical Research in Chinese Universities 2008年第6期24卷 756-761页

作者： CHEN Jie DONG Xin-shu guo xing-gang The Affiliated Tumor Hospital Harbin Medical University Harbin 150040 P. R. China

To explore the functional mechanism of Resveratrol against colon cancer cells ls174t and the growth of colon cancer tissue of tumor-bearing mice, MTT method was used to observe the functions of resveratrol for inhibition against cells ls174t in vitro. Transmission electron microscope was used to observe the cell apoptosis. FCM assay was performed to measure the change of the cell apoptosis rate and of cell cycle. RT-PCR method was used to detect the expressions of bcl-2 and bax mRNA. Western blot method was used to detect the expressions of bcl-2 and bax protein. Ceils ls174t were transplanted subcutaneously to nude mice to observe the effect of resveratrol on the growth of subcutaneously transplanted tumor, RT-PCR method was used to detect the expressions of bcl-2 and bax mRNA in the tumor tissue. Western blot method was used to detect the expressions of bcl-2 and bax protein in the tumor tissue. Resveratrol has an effect of inhibiting proliferation of cells ls174t in vitro（P〈0.01）. It is able to induce the apoptosis of cells ls174t, causing the decrease in the expression of bcl-2 and the increase in the expression of bax. Resveratrol could inhibit the growth of subcutaneously transplanted tumor of nude mice（P〈0.05）, causing the decrease in the expression of bcl-2 and the increase in the expression of bax. Resveratrol can inhibit the growth of cells 174t and the growth of subcutaneously transplanted tumor. The mechanism is possibly related to the induction of the cell apoptosis and the regulation of bcl-2/bax expression.

关键词： Resveratrol Colon cancer Tumor cell Cell apoptosis Nude mice

Tetraarsenic Tetrasulfide Induced Colon Cancer ls174t Cells Apoptosis

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Chemical Research in Chinese Universities 2009年第2期25卷 193-197页

作者： guo xing-gang DONG Xin-shu CHEN Jie The Affiliated Tumor Hospital of Harbin Medical University Harbin 150040 P. R. China

To explore the functional mechanism of tetraarsenic tetrasulfide（As4S4） against the growth and proliferation of colon cancer cells ls174t, MTT method was used to observe the functions of tetraarsenic tetrasulfide for the inhibition of cells ls174t in vitro. Transmission electron microscope was used to observe cell morphologies. FCM assay was performed to measure the change of cell cycle. RT-PCR method was used to detect the expressions of bcl-2 and bax mRNA. Westernblot method was used to detect the expressions of bcl-2 and bax protein. Tetraarsenic tetra- sulfide showed an inhibiting effect on the proliferation of cells ls174t in vitro（P〈0.01）. It induces the apoptosis of cells ls174t, which is related to the decrease in the expression of bcl-2 and the increase in the expression of bax.

关键词： Tetraarsenic tetrasulfide As484 Colon cancer Tumor cell Cell apoptosis

Formaldehyde increases intracellular calcium concentration in primary cultured hippocampal neurons partly through NMDA receptors and T-type calcium channels

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Neuroscience Bulletin 2012年第6期28卷 715-722页

作者： Ye-Nan Chi Xu Zhang Jie Cai Feng-Yu Liu guo-gang xing You Wan Neuroscience Research Institute and Department of Neurobiology Peking University Key Laboratory for Neuroscience Ministry of Education /Ministry of HealthPeking University

Objective Formaldehyde at high concentrations is a contributor to air pollution. It is also an endogenous metabolic product in cells, and when beyond physiological concentrations, has pathological effects on neurons. Formaldehyde induces mis-folding and aggregation of neuronal tau protein, hippocampal neuronal apoptosis, cognitive impairment and loss of memory functions, as well as excitation of peripheral nociceptive neurons in cancer pain models. Intracellular calcium （[Ca2＋]i） is an important intracellular messenger, and plays a key role in many pathological processes. The present study aimed to investigate the effect of formaldehyde on [Ca2＋]i and the possible involvement of N-methyl-D-aspartate receptors （NMDARs） and T-type Ca2＋ channels on the cell membrane. Methods Using primary cultured hippocampal neurons as a model, changes of [Ca2＋]i in the presence of formaldehyde at a low concentration were detected by confocal laser scanning microscopy. Results Formaldehyde at 1 mmol/L approximately doubled [Ca2＋]i. （2R）-amino-5-phosphonopentanoate （AP5, 25 μmol/L, an NMDAR antagonist） and mibefradil （MIB, 1 μmol/L, a T-type Ca2＋ channel blocker）, given 5 min after formaldehyde perfusion, each partly inhibited the formaldehyde-induced increase of [Ca：＋]i, and this inhibitory effect was reinforced by combined application of AP5 and MIB. When applied 3 min before formaldehyde perfusion, AP5 （even at 50μmol/L） did not inhibit the formaldehyde-induced increase of [Ca2＋]i, but MIB （1 μmol/L） significantly inhibited this increase by 70%. Conclusion These results suggest that formaldehyde at a low concentration increases [Ca2＋]i in cultured hippocampal neurons; NMDARs and T-type Ca2＋ channels may be involved in this process.

关键词： formaldehyde intracellular calcium neuronal activation NMDA receptors T-type calcium channels

Specific CYP450 Genotypes in the Chinese Population Affect Sorafenib Toxicity in HBV/HCV-associated Hepatocellular Carcinoma Patients

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Biomedical and Environmental Sciences 2018年第8期31卷 586-595页

作者： guo xing gang WANG Zhi Heng DONG Wei HE Xu Dong LIU Fu Chen LIU Hui The Third Department of Hepatic Surgery Eastern Hepatobiliary Surgery Hospital Second Military Medical University Respiratory and Endocrine Department The People's Hospital of Wuwei County

Objective The purpose of this study was to screen for frequencies of different CYP450 genotypes in the Chinese population and explore the relationship between sorafenib toxicity and CYP450 polymorphism. Methods A total of 600 peripheral blood samples were obtained from two groups for this study. The first group of 300 samples were from Chinese patients with HBV/HCV-associated HCC, while the remaining 300 samples were from a healthy population of recruited subjects. Allele-specific PCR and long-fragment gene sequencing was used to identify the frequencies of CYP450 polymorphism. Aflatoxin-induced HCC rat models expressing CYP3A4*1, CYP3A5*3, CYP2C19*2, and CYP2D6*10 were established and treated with sorafenib at certain time points. Hepatic and renal function, along with plasma concentration of sorafenib, were monitored regularly. Results The most common forms of CYP mutations in the Chinese population were identified. The levels of sorafenib plasma concentration, as well as damage to hepatic and renal function in aflatoxin-induced HCC rat models varied significantly across the different CYP genotypes. Conclusion The mutational frequencies of CYP3A5, CYP3A4, CYP2C19, and CYP2D6 genotypes varied among different ethnic groups and populations. Individuals with CYP3A5*3 demonstrated minimal sorafenib metabolism, which led to severe hepatic and renal damage. Inter-individual variability in sorafenib-toxicity may be interpreted by CYP450 genetic polymorphisms, suggesting that identification of CYP polymorphism within a certain population should be considered in sorafenib therapy.

关键词： Sorafenib Hepatocellular carcinoma CYP450 polymorphism Inter-individual adverse events

Formaldehyde up-regulates TRPV1 through MAPK and PI3K signaling pathways in a rat model of bone cancer pain

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Neuroscience Bulletin 2012年第2期28卷 165-172页

作者： Ying Han Yan Li Xlng Xlao Jia Liu Xiang-Ling Meng Feng-Yu Liu guo-gang xing You Wan Neurosczence Research Institute Department of Neurobiology School of Basic Medical Sciences Key Laboratory forNeuroscience The Ministry of Education / The Ministry of Health Peking University Beijing 100191 China

Objective Our previous study showed that tumor tissue-derived formaldehyde at low concentrations plays an important role in bone cancer pain through activating transient receptor potential vanilloid subfamily member 1 （TRPV 1）. The present study further explored whether this tumor tissue-derived endogenous formaldehyde regulates TRPV1 expres- sion in a rat model of bone cancer pain, and if so, what the possible signal pathways are during the development of this type of pain. Methods A rat model of bone cancer pain was established by injecting living MRMT-1 tumor cells into the tibia. The formaldehyde levels were determined by high performance liquid chromatography, and the expression of TRPV1 was examined with Western blot and RT-PCR. In primary cultured dorsal root ganglion （DRG） neurons, the ex- pression of TRPV1 was assessed after treatment with 100 ~tmol/L formaldehyde with or without pre-addition of PD98059 [an inhibitor for extracellular signal-regulated kinase], SB203580 （a p38 inhibitor）, SP600125 [an inhibitor for c-Jun N- terminal kinase], BIM [a protein kinase C （PKC） inhibitor] or LY294002 [a phosphatidylinositol 3-kinase （PI3K） inhibi- tor]. Results In the rat model of bone cancer pain, formaldehyde concentration increased in blood plasma, bone marrow and the spinal cord. TRPV1 protein expression was also increased in the DRG. In primary cultured DRG neurons, 100 p^mol/L formaldehyde significantly increased the TRPV1 expression level. Pre-incubation with PD98059, SB203580, SP600125 or LY294002, but not BIM, inhibited the formaldehyde-induced increase of TRPV1 expression. Conclusion Formaldehyde at a very low concentration up-regulates TRPV1 expression through mitogen-activated protein kinase and PI3K, but not PKC, signaling pathways. These results further support our previous finding that TRPV1 in peripheral after- ents plays a role in bone cancer pain.

关键词： formaldehyde TRPV1 cancer pain mitogen-activated protein kinase phosphatidylinositol 3-kinase

Research on the influences of motion characteristics of jetting projectile charge under water

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Defence Technology（防务技术） 2024年第3期33卷 411-425页

作者： xing Chen Yong-gang Lu Institute of Systems Engineering China Academy of Engineering PhysicsMianyang 621900SichuanChina

Shaped charge warhead is important for enhancing the damage performance of underwater *** paper used finite element analysis software and based on JPC water penetration experiments to examine the influence of liner parameters(wall thickness,material),charge aspect ratio,and stand-off distance on the movement characteristics of JPC in *** findings reveal that the head diameter of the JPC increases and experiences significant erosion after entering the water,the effective length of the JPC in water undergoes two distinct phases:a growth phase and a decrease phase,with the velocity of the JPC decaying *** the liner thickness,stand-off distance and the charge aspect ratio can improve the erosion resistance and the velocity retention capacity of the *** optimal ranges for liner thickness and stand-off distance are 0.0363D_(k) to 0.0545D_(k)(D_(k) is the charge diameter),the stand-off distance should be within 1.0D_(k).After the charge aspect ratio higher than 1.25,the charge structure exerts minimal influence the movement characteristics of the JPC in *** density plays a crucial role in the velocity decay pattern of the JPC during *** with higher densities exhibit superior velocity retention capabilities in water,with the velocity decay pattern converging if the densities are ***,copper,tantalum and tungsten liners are deemed appropriate for underwater shaped charge ***,the results will provide an important reference for the design of underwater shaped charge warhead.

关键词： JPC Movement characteristics Underwater penetration Numerical simulation

Configuration Synthesis and Grasping Performance Analysis of Multi-Loop Coupling Capture Mechanism for Launch and Recovery of Torpedo-Shaped Autonomous Underwater Vehicle

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China Ocean Engineering 2024年第3期38卷 453-466页

作者： ZHANG guo-xing XIA Xin-lu guo Jin-wei School of Mechanical Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

Research of capture mechanisms with strong capture adaptability and stable grasp is important to solve the problem of launch and recovery of torpedo-shaped autonomous underwater vehicles(AUVs).A multi-loop coupling capture mechanism with strong adaptability and high retraction rate has been proposed for the launch and recovery of torpedo-shaped AUVs with different morphological ***,the principle of capturing motion retraction is described based on the appearance characteristics of torpedo-shaped AUVs,and the configuration synthesis of the capture mechanism is carried out using the method of constrained chain ***,the screw theory is employed to analyze the degree of freedom(DoF)of the capture ***,the 3D model of the capture mechanism is established,and the kinematics and dynamics simulations are carried *** with the capture orientation requirements of the capture mechanism,the statics and vibration characteristics analyses are carried ***,considering the capture process and the underwater working environment,the motion characteristics and hydraulics characteristics of the capture mechanism are ***,a principle prototype is developed and the torpedo-shaped AUVs capture experiment is *** work provides technical reserves for the research and development of AUV capture special equipment.

关键词： capture mechanism torpedo-shaped AUVs configuration synthesis launch and recovery grasping performance analysis

Responses of Primary Afferent Fibers to Acupuncture-Like Peripheral Stimulation at Different Frequencies:Characterization by Single-Unit Recording in Rats

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Neuroscience Bulletin 2020年第8期36卷 907-918页

作者： Ran Huo Song-Ping Han Feng-Yu Liu Xiao-Jing Shou Ling-Yu Liu Tian-Jia Song Fu-Jun Zhai Rong Zhang guo-gang xing Ji-Sheng Han Neuroscience Research Institute Peking UniversityBeijing 100191China Department of Neurobiology Peking University School of Basic Medical SciencesBeijing 100191China Key Laboratory for Neuroscience Ministry of Education/National Health and Family Planning CommissionPeking UniversityBeijing 100191China Department of Radiology Peking University Third HospitalBeijing 100191China Department of Integration of Chinese and Western Medicine Peking University School of Basic Medical SciencesBeijing 100191China

The pain-relieving effect of acupuncture is known to involve primary afferent nerves(PANs) via their roles in signal transmission to the *** single-unit recording in rats,we characterized the generation and transmission of electrical signals in Aβ and Aδ fibers induced by acupuncture-like ***-like signals were elicited in PANs using three techniques:manual acupuncture(MAc),emulated acupuncture(EAc),and electro-acupuncture(EA)-like peripheral electrical stimulation(PES).The discharges evoked by MAc and EAc were mostly in a burst pattern with average intra-burst and inter-burst firing rates of 90 Hz and 2 Hz,*** frequency of discharges in PANs was correlated with the frequency of *** highest discharge frequency was 246 Hz in Aβ fibers and 180 Hz in Aδ ***,EA in a dense-disperse mode(at alternating frequency between 2 Hz and 15 Hz or between 2 Hz and 100 Hz) best mimics *** of EA output>250 Hz appear to be obsolete for pain relief.

关键词： Acupuncture Peripheral electrical stimulation Dorsal root Primary afferent fiber Electrophysiology Single unit recording

Fullerenes and derivatives as electrocatalysts: Promises and challenges

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Green Energy & Environment 2024年第1期9卷 7-27页

作者： Kun guo Ning Li Lipiao Bao xing Lu State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China

Carbon-based metal-free nanomaterials are promising alternatives to precious metals as electrocatalysts of key energy storage and conversion *** paramount signiﬁcance are the establishment of design principles by understanding the catalytic mechanisms and identifying the active *** from sp2-conjugated graphene and carbon nanotube,fullerene possesses unique characteristics that are growingly being discovered and exploited by the electrocatalysis *** instance,the well-deﬁned atomic and molecular structures,the good electron afﬁnity to tune the electronic structures of other substances,the intermolecular self-assembly into superlattices,and the on-demand chemical modiﬁcation have endowed fullerene with incomparable advantages as electrocatalysts that are otherwise not applicable to other carbon *** increasing studies are being reported on this intriguing topic,it is necessary to provide a state-of-the-art overview of the recent *** review takes such an initiative by summarizing the promises and challenges in the electrocatalytic applications of fullerene and its *** content is structured according to the composition and structure of fullerene,including intact fullerene(e.g.,fullerene composite and superlattices)and fullerene derivatives(e.g.,doped,endohedral,and disintegrated fullerene).The synthesis,characterization,catalytic mechanisms,and deﬁciencies of these fullerene-based materials are explicitly *** conclude it by sharing our perspectives on the key aspects that future efforts shall consider.

关键词： Fullerene Fullerene derivative Metal-free catalyst Structural defect Electrocatalyst

The dynamics of traveling wavefronts for a model describing host tissue degradation by bacteria

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International Journal of Biomathematics 2024年第3期17卷 265-287页

作者： xing-xing Yang guo-Bao Zhang Ge Tian College of Mathematics and Statistics Northwest Normal University Lanzhou Gansu 730070P.R.China

In this paper,we mainly investigate the dynamics of traveling wavefronts for a model describing host tissue degradation by *** first establish the existence of spreading speed,and show that the spreading speed coincides with the minimal wave speed of traveling ***,a lower bound estimate of the spreading speed is ***,we prove that the traveling wavefronts with large speeds are globally exponentially stable,when the initial perturbation around the traveling wavefronts decays exponentially asχ→-∞,but the initial perturbation can be arbitrarily large in other *** adopted methods are the weighted energy and the squeezing technique.

关键词： Host tissue degradation bacterial infection traveling wavefronts minimal wave speed stability