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Expression of cyclin-dependent kinase inhibitor genes induces apoptosis in human hepatoma cell line

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Chinese Science Bulletin 1997年第23期42卷 2000-2005页

作者： Ren, CC tian, PK Qu, SM Teng, QS Jiang, hq Zheng, YH Ren, SJ Gu, JR Shanghai Canc Inst Natl Lab Oncogenes & Related Genes Shanghai 200032 Peoples R China

APOPTOSIS is an active, inherently programmed cell death, which has typical morphologicaland biochemical characteristics. Cell death during embryonic development, shaping of the Tand B lymphocyte and tissue dystrophy related to endocrine is designated a physiological apop-tosis by which cell numbers can be effectively controlled. As a process opposite to cell division,there is a balance between apoptosis and cell proliferation. A tumor will develop once the bal-ance is disturbed and the cell division is more rapid than the cell death. Also, apoptosis is un-der the control of multiple molecular components, while cell division is under the control of thecell cycle engine. The precise control of cell proliferation and differentiation is essential for

关键词： apoptosis cyclin-dependent kinase inhibitor hepatoma.

Multi-scale analysis of ecosystem services trade-offs in an ecotone in the Eastern Margin of the Qinghai-Tibetan Plateau

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Journal of Mountain Science 2021年第11期18卷 2803-2819页

作者： GONG Jie XU Cai-xian YAN Ling-ling ZHU Yue-hua ZHANG Yun-xia JIN tian-tian Key Laboratory of Western China's Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China

Understanding the trade-offs among ecosystem services(ESs)at multiple scales is a key challenge to effective environmental ***,the scale effect of ESs trade-offs in the Qinghai-Tibetan Plateau(QTP)has received little *** study investigated the scale effects of ESs trade-offs in Bailongjiang Watershed(BLJW),a typical transitional ecotone from the Loess Plateau to the Tibetan Plateau with multiple ESs,intensive human activities and frequent geological disasters in the Eastern Margin of the QTP,*** key ESs including food supply(FS),soil conservation(SC),water conservation(WC),and habitat quality(hq)in BLJW in 1990,2002,and 2016 were mapped to analyze the scale effects at the watershed,county,and township *** results indicated varying scale-related temporal and spatial relationships among FS,SC,WC,and *** trade-offs between FS-SC and FS-WC initially increased and then decreased during 1990-2002 and 2002-2016,respectively,while the trade-offs between SC-WC,SC-hq,hq-WC,and hq-FS first decreased and then increased at the same *** magnitudes of the trade-offs among the four ESs are in the order of watershed scale>township scale>county *** the major land-use types in BLJW,the trade-offs between WC-FS and between hq-FS in farmland and grassland were higher than those of other land *** is a strong trade-off between SC-hq in forestland and a weak trade-off between SC-WC in farmland and *** trade-offs between the six ESs pairs varied and were scale-dependent mainly due to spatial heterogeneity in the landscape and in human *** the ESs trade-offs at the watershed,county,and township scales provides a scientific basis for the formulation of environmental management strategies at appropriate spatial *** the BLJW watershed scale,more attention should be paid on farmland and grassland planning and its management,also,forestland should be enlarged if *** the county and townshi

关键词： Ecosystem services Multi-scaleanalysis Spatiotemporal change Trade-offs Scale effects

Synthesis and Property of Flame Retardant Epoxy Resins Modified with 2-（Diphenylphosphinyl）-l,4-benzenediol

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Chemical Research in Chinese Universities 2014年第5期30卷 868-873页

作者： tian Xiujuan WANG Zhongwei YU Qing WUQingyu GAO Jun School of Materials Science and Engineering Shandong University of Science and Technology Qingdao 266590 P. R. China School of Chemical and Environmental Engineering Shandong University of Science and Technology Qingdao 266590 P. R. China

2-（Diphenylphosphinyl）-1,4-benzenediol（DPO-hq） was synthesized by the reaction of diphenylphos- phine oxide（DPO） with 1,4-benzoquinone（BQ）, and characterized by Fourier transform infrared（FTIR）, and nuclear magnetic resonance（1H NMR, 13C NMR, 31p NMR） spectrometries. The thermal stability of DPO-hq was investi- gated by thermogravimetric analysis（TGA）. Flame retardant epoxy resin was synthesized based on DPO-hq. The thermal properties and burning performance of cured epoxy resins were measured by differential scanning calorime- try（DSC）, thermogravimetric analysis（TGA）, limited oxygen index（LOI） and vertical burning test（UL-94V）. The morphologies of cured epoxy resins after combustion were investigated by scanning electron microscopy（SEM） and electron probe microanalysis（EPMA）. Moreover, the thermal stability（both in air and in N2） of DPO-hq and its cured epoxy resin was compared with that of 10-（2,5-dihydroxyphenyl）-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10- oxide（DOPO-hq） and its cured epoxy resin. The thermal stability of DPO-hq is comparable with that of DOPO-hq, while the thermal stability of cured epoxy resin based on DPO-hq is better than that based on DOPO-hq.

关键词： Flame retardant Thermal stability Epoxy resin Phosphorus Burning behavior

Intelligent laser-induced graphene sensor for multiplex probing catechol isomers

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Chinese Chemical Letters 2024年第7期35卷 227-234页

作者： tian Cao Xuyin Ding Qiwen Peng Min Zhang Guoyue Shi School of Chemistry and Molecular Engineering Shanghai Key Laboratory for Urban Ecological Processes and Eco-RestorationEast China Normal UniversityShanghai 200241China

Herein,we unveil the intelligent detection of multiple catechol isomers in complex environments utilizing both laser-induced graphene(LIG)and artificial neural network(ANN).The large scale-up manufacturing of LIG-based sensors(LIGS)with three-electrode configuration on polyimide(PI)is achieved by direct laser-writing and screen-printing *** LIGS shows excellent electrochemical performance toward catechol isomers,i.e.,hydroquinone(1,4-dihydroxybenzene,hq),catechol(1,2-dihydroxybenzene,CT),and resorcinol(1,3-dihydroxybenzene,RC),with a low limit of detection(LOD)(CC,0.079μmol/L;hq,0.093μmol/L;RC,1.18μmol/L).Moreover,the ANN model is developed for machine-intelligent to predict concentrations of catechol isomers under an interfering environment via a single *** six unique parameters extracted from the differential pulse voltammetry(DPV)response,the machine learning-based regression provides a coefficient of correlation with 0.998 and is able to correctly predict the total and individual concentrations in complex river ***,this work provides a guide for the preparation and application of LIGS via facile and cost-efficient mass production and the development of an intelligent sensing platform based on the ANN model.

关键词： Laser-induced graphene Phenolic pollutants Electrochemical detection Artificial neural network

Human health ambient water quality criteria for 13 heavy metals and health risk assessment in Taihu Lake

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Frontiers of Environmental Science & Engineering 2022年第4期16卷 15-25页

作者： Liang Cui Ji Li Xiangyun Gao Biao tian Jiawen Zhang Xiaonan Wang Zhengtao Liu State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Faculty of Land and Resources Engineering Kunming University of Science and TechnologyKunming 650093China

Heavy metals are widely concerning because of their toxicity,persistence,non-degradation and bioaccumulation *** health ambient water quality criteria(AWQC)are specific levels of chemicals that can occur in water without harming human *** present,most countries do not consider the effects of aquatic vegetables in deriving human health ***,the intake of aquatic vegetables(Brasenia schreberi)was added to the derivation of human health AWQC and a health risk assessment for 13 heavy metals in Taihu *** human health AWQC(consumption of water,fish and aquatic vegetables)values of 13 heavy metals ranged from 0.04(Cd)to 710.87μg/L(Sn),and the intake of *** had a very significant effect on the human health AWQC for Cu,with a more than 62-fold *** hazard quotients of As(2.8),Cd(1.6),Cr(1.4)and Cu(4.86)were higher than the safe level(hq=1),indicating that As,Cd,Cr and Cu in Taihu Lake posed a significant health *** analysis showed that the contribution rate of *** intake to the human health risk from Cu was 91.6%,and all results indicated that the risk of Cu in *** to human health should be of particular *** study adds the consideration of aquatic vegetable consumption to the traditional method of human health AWQC derivation and risk assessments for the first time,and this approach can promote the development of risk assessments and water quality criteria.

关键词： Heavy metals Human health ambient water quality criteria Taihu Lake Health risk assessment Contribution rate

Analysis of the electron transfer pathway in small laccase by EPR and UV-vis spectroscopy coupled with redox titration

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Magnetic Resonance Letters 2024年第3期4卷 52-59页

作者： Lu Yu Aokun Liu Jian Kuang Ruotong Wei Zhiwen Wang Changlin tian High Magnetic Field Laboratory Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei230031China Department of Endocrinology Institute of Endocrine and Metabolic DiseaseThe First Affiliated Hospital of USTCDivision of Life Sciences and MedicineHefei National Research Center for Physical Sciences at the MicroscaleJoint Center for Biological Analytical ChemistryAnhui Engineering Laboratory of Peptide DrugAnhui Laboratory of Advanced Photonic Science and TechnologyUniversity of Science and Technology of ChinaHefei230026China

Bacterial small laccases(SLAC) are promising industrial biocatalysts due to their ability to oxidize a broad range of substrates with exceptional thermostability and tolerance for alkaline p H. Electron transfer between substrate, copper centers, and O2is one of the key steps in the catalytic turnover of SLAC. However, limited research has been conducted on the electron transfer pathway of SLAC and SLAC-catalyzed reactions, hindering further engineering of SLAC to produce tunable biocatalysts for novel applications. Herein, the combinational use of electron paramagnetic resonance(EPR) and ultraviolet-visible(UV-vis) spectroscopic methods coupled with redox titration were employed to monitor the electron transfer processes and obtain further insights into the electron transfer pathway in SLAC. The reduction potentials for type 1 copper(T1Cu), type 2 copper(T2Cu) and type 3copper(T3Cu) were determined to be 367 ± 2 mV, 378 ± 5 m V and 403 ± 2 mV,respectively. Moreover, the reduction potential of a selected substrate of SLAC, hydroquinone(hq), was determined to be 288 mV using cyclic voltammetry(CV). In this way, an electron transfer pathway was identified based on the reduction potentials. Specifically,electrons are transferred from hq to T1Cu, then to T2Cu and T3Cu, and finally to ***, superhyperfine splitting observed via EPR during redox titration indicated a modification in the covalency of T2Cu upon electron uptake, suggesting a conformational alteration in the protein environment surrounding the copper sites, which could potentially influence the reduction potential of the copper sites during catalytic processes. The results presented here not only provide a comprehensive method for analyzing the electron transfer pathway in metalloenzymes through reduction potential measurements, but also offer valuable insights for further engineering and directed evolution studies of SLAC in the aim for biotechnological and industrial applications.

关键词： Electron paramagnetic resonance Redox titration Electron transfer Reduction Potential Small laccase

Glutamine addiction and therapeutic strategies in pancreatic cancer

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World Journal of Gastrointestinal Oncology 2023年第11期15卷 1852-1863页

作者： Lin-Lin Ren Tao Mao Pin Meng Li Zhang Hong-Yun Wei Zi-Bin tian Department of Gastroenterology The Affiliated Hospital of Qingdao UniversityQingdao 266000Shandong ProvinceChina Department of Pathology The Affiliated Hospital of Qingdao UniversityQingdao 266000China

Pancreatic cancer remains one of the most lethal diseases worldwide owing to its late diagnosis,early metastasis,and poor *** current therapeutic options are limited,there is an urgent need to investigate novel targeted treatment *** cancer faces significant metabolic challenges,principally hypoxia and nutrient deprivation,due to specific microenvironmental constraints,including an extensive desmoplastic stromal *** cancer cells have been shown to rewire their metabolism and energy production networks to support rapid survival and *** glucose uptake and glycolytic pathway activity during this process have been extensively ***,growing evidence suggests that pancreatic cancer cells are glutamine *** a nitrogen source,glutamine directly(or indirectly via glutamate conversion)contributes to many anabolic processes in pancreatic cancer,including amino acids,nucleobases,and hexosamine *** also plays an important role in redox homeostasis,and when converted toα-ketoglutarate,glutamine serves as an energy and anaplerotic carbon source,replenishing the tricarboxylic acid cycle *** present study aims to provide a comprehensive overview of glutamine metabolic reprogramming in pancreatic cancer,focusing on potential therapeutic approaches targeting glutamine metabolism in pancreatic cancer.

关键词： Pancreatic cancer Glutamine metabolism Cancer treatment Therapeutic strategies

Metabolic profile analysis of free amino acids in experimental autoimmune uveoretinitis rat plasma

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International Journal of Ophthalmology(English edition) 2019年第1期12卷 16-24页

作者： Jun-Guo Guo Xin-Miao Guo Xing-Rong Wang Jing-Zhen tian Hong-Sheng Bi College of Pharmacy Shandong University of Traditional Chinese Medicine Shandong Provincial Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Therapy of Ocular Diseases Eye Institute Shandong University of Traditional Chinese Medicine School of Management Shandong University of Traditional Chinese Medicine Affiliated Eye Hospital Shandong University of Traditional Chinese Medicine

AIM: To determine the differences of amino acid(AA) levels in experimental autoimmune uveoretinitis(EAU). METHODS: AA analysis of the plasma samples in EAU rats induced by interphotoreceptor retinoid-binding protein emulsion were performed with high performance liquid chromatography(HPLC) and phenylisothiocyanate(PITC) pre-column derivation methods were performed. Using partial least squares discriminant analysis(PLS-DA), the potential biomarkers were identified in EAU rat plasma, and the metabolic pathways related to EAU were further analyzed. RESULTS: The method results showed that linear(r≥0.9957), intra-day reproducible [relative standard deviation(RSD)=0.04%-1.33%], inter-day reproducible(RSD=0.06%-2.07%), repeatability(RSD=0.03%-0.89%), stability(RSD=0.05%-2.48%) and recovery(RSD=1.98%-4.39%), with detection limits of 0.853-11.4 ng/mL. The metabolic profile in EAU rats was different from that in the control groups five AAs concentrations were increased and nine AAs were reduced. Moreover, five metabolic pathways were related to the development of EAU. CONCLUSION: The developed method is a simple, rapid and convenient for determination of AAs in EAU rat plasma, and these findings will provide a comprehensiveinsight on the metabolic profiling of the pathological changes in EAU.

关键词： experimental autoimmune uveoretinitis phenylisothiocyanate high performance liquid chromatography amino acid metabolic profile rat

The Effect of the Structure of Polychlorinated Biphenyls on their Hydroxylation, Oxidation,and Glutathionyl Conjugation Reactions

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Biomedical and Environmental Sciences 2013年第2期26卷 138-147页

作者： SONG Er Qun MA Xiao Yan tian Xing Guo LIU Jing LIU Li Chao DONG Hui SONG Yang Key Laboratory of Luminescence and Real-Time Analysis Ministry of EducationCollege of PharmaceuticalSciencesSouthwest University

Objective To compare the nature of the metabolites formed from the phase I metabolism （hydroxylation and oxidation） and phase II metabolism （glutathionyl conjugation） of PCBs that have different chlorine substitution patterns. To discuss the structure-activity relationships and metabolic mechanisms of PCBs. Methods 4-CI-biphenyl （PCB3）, 4,4＇-CI-biphenyl （PCB15）, 3,4,3＇,4＇-Cl-biphenyl （PCB77） were used for in vitro metabolic study. LC/MS and UV-Vis studies were performed for metabolites identification. Results The cytochrome P-450 catalyzed hydroxylation rate decreased as the number of chlorine substitutions increased. In this reaction, PCB3 was fully metabolized, approximately half of the PCB15 was metabolized and PCB77 was not metabolized at all. The oxidation rate of PCB15-hq was higher than that of PCB3-HO. under various oxidation conditions. The LC/MS and UV-Vis data suggest that in the conjugation reaction of PCB15-Q and GSH, the Michael addition reaction occurs preferentially over the displacement reaction. Conclusion The metabolic profiles of polychlorinated biphenyls （PCBs） are dramatically affected by chlorine substitution patterns. It is suggested that the metabolic profiles of PCBs are related to their chlorine substitution patterns, which may have implications for the toxicity of PCB exposure.

关键词： PCB metabolism Cytochrome P450 Glutathione Quinone Hydroquinone