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Journal of Environmental Sciences 2003年第3期15卷 289-295页

作者： ZHOU Ke-bin CHEN Hong-de TIAN Qun SHEN Di-xin XU Xiao-bai Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China.

The effects of reactant composition and steam on propane combustion over Pd/LaFe_ 0.8Co_ 0.2O_3 catalyst were investigated. Propane conversion and the oxidation state of palladium were strongly affected by the redox ratio of reactants. Higher propane conversion could be obtained under rich conditions and explained as a complex balance between oxidation and steam reforming. Water produced in the oxidation could promote the propane conversion by steam reforming. However, the presence of excess steam would bring about inhibition.

关键词： propane palladium perovskite redox ratio steam

Quantitative redox imaging biomarkers for studying tissue metabolic state and its heterogeneity

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Journal of Innovative Optical Health Sciences 2014年第2期7卷 109-128页

作者： He N.Xu Lin Z.Li Department of RadiologyBrtton Chance Laboratory of Redoa Imaging Johnson Research Foundation Departmentof Biochemistry and BiophysicsPerelman School of MedicineUniversity of Pennsyluania PhiladelphiaPAUSA

NAD+/NADH redox state has been implicated in many diseases such as cancer and diabetes aswell as in the regulation of embryonic development and aging,To fluorimetrically sssthemitochondrial redox state,*** and co-workers measured the fluorescence of NADH andoxidized flavoproteins(Fp)including favin-adenine-dinucleotide(FAD)and demonstrated theirratio(*** redox ratio)is a sensitive indicator of the mitochondrial redox states.,The Chanceredox sca mer was built to simult aneously measure NADH and Fp in tisue at submilimeter scalein 3D using the freeze-trap *** paper summarizes our recent research experience,development and new applications of the redox scanning technique in collaboration with *** beginning in *** initiated or actively involved in many of the projectsduring the last several years of his *** advanced the redox scanning technigue by measuringthe nominal concentrations(in reference to the frozen solution standards)of the endogenousfuorescent analy tes,i.e.,[NADH]and[rp]to quantify the redox ratios in various *** advancement has enabled us to identify an array of the redox indices as quantitativeimaging,biomarkers(including[NADH],[Fp],[Fp]/[NADH]+[Fp],[NADH]/[Fp],and theirstandard deviations)for studying some important biological questions on cancer and normaltsue *** found that the redox indices were asociated or changed with(NADH)tumorigenesis(cancer versus non-cancer of human breast tisue biopsies);(2)tumor metastaticpotential;(3)tumor glucose uptake;(4)tumor p53 stat us;(5)PI3K pathway activation in pre-malignant tissue;(6)therapeutic ffects on tumors;(7)embryonic stem cell diferentiation;(8)the heart under fasting,Together,our work demonstrated that the tisue redox indices obtainedfrom the redox scanning technique may provide usefil information about tisue met abolism and physiology status in normal and diseased *** Chance redox scanner and other redoximaging techniques may ha

关键词： Tumor progresion mitochondria met astasis met astatic potential pre-malignancy NADH Fp FAD redox ratio

IMAGING redox STATE HETEROGENEITY WITHIN INDIVIDUAL EMBRYONIC STEM CELL COLONIES

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Journal of Innovative Optical Health Sciences 2011年第3期4卷 279-288页

作者： HE N.XU RUSSELL C.ADDIS DAVIDA F.GOINGS SHOKO NIOKA BRITTON CHANCE JOHN D.GEARHART LIN Z.LI Molecular Imaging Laboratory Department of Radiology University of PennsylvaniaSchool of Medicine PhiladelphiaPA 19104USA Institute for Regenerative Medicine and Department of Cell and Developmental Biology University of Pennsylvania School of Medicine PhiladelphiaPA 19104USA Britton Chance Laboratory of redox Imaging Johnson Research Foundation Department of Biochemistry and Biophysics University of Pennsylvania School of Medicine PhiladelphiaPA 19104USA Institute of Translational Medicine and Therapeutics University of Pennsylvania PhiladelphiaPA 19104USA

redox state mediates embryonic stem cell(ESC)differentiation and thus offers an important complementary approach to understanding the pluripotency of stem *** redox ratio(NADH/(Fp t NADH)),where NADH is the reduced form of nicotinamide adenine dinucleotide and Fp is the oxidizedflavoproteins,has been established as a sensitive indicator of mitochondrial redox *** this paper,we report our redox imaging data on the mitochondrial redox state of mouse ESC(mESC)colonies and the implications *** low-temperature NADH/Fp redox scanner was employed to image mESC colonies grown on a feeder layer of gamma-irradiated mouse embryonicfibroblasts(MEFs)on glass cover *** result showed significant heterogeneity in the mitochondrial redox state within individual mESC colonies(size:~200-440μm),exhibiting a core with a more reduced state than the *** more reduced state positively correlates with the expression pattern of Oct4,a well-established marker of *** observation is thefirst to show the heterogeneity in the mitochondrial redox state within a mESC colony,suggesting that mitochondrial redox state should be further investigated as a potential new biomarker for the stemness of embryonic stem cells.

关键词： redox imaging pluripotency NADH flavoproteins redox ratio

QUANTITATIVE redox SCANNING OF TISSUE SAMPLES USING A CALIBratioN PROCEDURE

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Journal of Innovative Optical Health Sciences 2009年第4期2卷 375-385页

作者： HE N.XU BAOHUA WU SHOKO NIOKA BRITTON CHANCE LIN Z.LI Molecular Imaging Laboratory Department of Radiology University of PennsylvaniaPhiladelphia PA 19104USA Johnson Research Foundation Department of Biochemistry and Biophysics University of Pennsylvania PA 19104USA

The fluorescence properties of reduced nicotinamide adenine dinucleotide(NADH)and oxidizedflavoproteins(Fp)including flavin adenine dinucleotide(FAD)in the respiratory chain are sensitive indicators of intracellular metabolic states and have been applied to the studies of mitochondrial function with energy-linked *** redox scanner,a three-dimensional(3D)low temperature imager previously developed by Chance et al.,measures the in vivo metabolicproperties of tissue samples by acquiring fluorescence images of NADH and *** redox ratios,***/(Fp+NADH)and NADH/(Fp+NADH),provided a sensitive index of the mitochondrialredox state and were determined based on relative signal intensity *** we report thefurther development of the redox scanning technique by using a calibration method to quantifythe nominal concentration of the fluorophores in *** redox scanner exhibited very goodlinear response in the range of NADH concentration between 165–1318µM and Fp between90–720µM using snap-frozen solution *** samples such as human tumor mousexenografts and various mouse organs were redox-scanned together with adjacent NADH and Fpstandards of known concentration at liquid nitrogen *** nominal NADH and Fpconcentrations as well as the redox ratios in the tissue samples were quantified by normalizing the tissue NADH and Fp fluorescence signal to that of the snap-frozen solution *** calibration procedure allows comparing redox images obtained at different time,independent of instrument *** quantitative multi-slice redox images revealed heterogeneity inmitochondrial redox state in the tissues.

关键词： NADH flavoprotein redox ratio mitochondria tissue heterogeneity

MITOCHONDRIAL redox IMAGING FOR CANCER DIAGNOSTIC AND THERAPEUTIC STUDIES

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Journal of Innovative Optical Health Sciences 2009年第4期2卷 325-341页

作者： LIN Z.LI HE N.XU MAHSA RANJI SHOKO NIOKA BRITTON CHANCE Department of Radiology School of Medicine University of PennsylvaniaB6 Blockley Hall423 Guardian Drive PhiladelphiaPA 19104-6069USA The Institute for Translational Medicine and Therapeutics School of Medicine University of Pennsylvania PhiladelphiaPA 19104USA Biophotonics Laboratory Department of Electrical Engineering and Computer Science University of Wisconsin-Milwaukee MilwaukeeWI 53211USA Johnson Research Foundation Department of Biochemistry and Molecular Biophysics School of Medicine University of Pennsylvania 250 Anatomy Chemistry BuildingPhiladelphiaPA 19104USA

Mitochondrial redox states provide important information about energy-linked biological processes and signaling events in tissues for various disease phenotypes including *** redox scanning method developed at the Chance laboratory about 30 years ago has allowed 3D highresolution(∼50×50×10µm^(3))imaging of mitochondrial redox state in tissue on the basis of the fluorescence of NADH(reduced nicotinamide adenine dinucleotide)and Fp(oxidized flavoproteins including flavin adenine dinucleotide,i.e.,FAD).In this review,we illustrate its basic principles,recent technical developments,and biomedical applications to cancer diagnostic and therapeutic studies in small animal *** developed calibration procedures for the redox imaging using reference standards allow quantification of nominal NADH and Fp concentrations,and the concentration-based redox ratios,e.g.,Fp/(Fp+NADH)and NADH/(Fp+NADH)in *** calibration facilitates the comparison of redox imaging results acquired for different metabolic states at different times and/or with different instrumental settings.A redox imager using a CCD detector has been developed to acquire 3D images faster and with a higher in-plane resolution down to 10µ*** vivo imaging and in vivo imaging of tissue mitochondrial redox status have been demonstrated with the CCD *** of tissue redox imaging in small animal cancer models include metabolic imaging of glioma and myc-induced mouse mammary tumors,predicting the metastatic potentials of human melanoma and breast cancer mouse xenografts,differentiating precancerous and normal tissues,and monitoring the tumor treatment response to photodynamic *** future directions for the development of redox imaging are also discussed.

关键词： redox ratio reduced nicotinamide adenine dinucleotide NADH flavoprotein flavin adenine dinucleotide FAD calibration

Optical redox imaging of ANT1-de-cient muscles

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Journal of Innovative Optical Health Sciences 2024年第1期17卷 135-140页

作者： He N.Xu Ryan M.Morrow Min Feng Huaqing Zhao Douglas Wallace Lin Z.Li Britton Chance Laboratory of redox Imaging Department of Radiology Perelman School of Medicine University of Pennsylvania PhiladelphiaPA 19104USA Center for Mitochondrial and Epigenomic Medicine Children's Hospital of Philadelphia Research Institute Philadelphia PA 19104USA Center for Biostatistics and Epidemiology Lewis Katz School of Medicine at Temple University Philadelphia PA 19140USA

Adenine nucleotide translocator(ANT)is a mitochondrial protein involved in the exchange of ADP and ATP across the mitochondrial inner *** plays a crucial role in cellular energy metabolism by facilitating the transport of ATP synthesized within the mitochondria to the *** isoform ANT1 predominately expresses in cardiac and skeletal *** or dysregulation in ANT1 have been implicated in various mitochondrial disorders and neuromuscular *** aimed to examine whether ANT1 deletion may affect mitochondrial redox state in our established ANT1-de-cient *** and quadriceps resected from age-matched wild type(WT)and ANT1-de-cient mice were snap-frozen in liquid *** Chance redox scanner was utilized to perform 3D optical redox *** sample underwent scanning across 3–5 *** averaging analysis showed no signi-cant differences in the redox indices(NADH,flavin adenine dinucleotide containing-flavoproteins Fp,and the redox ratio Fp/(NADH+Fp)between WT and ANT1-de-cient ***,quadriceps had higher Fp than hearts in both groups(p¼0:0004 and 0.01,respectively).Furthermore,the quadriceps were also more oxidized(a higher redox ratio)than hearts in WT group(p¼0:004).NADH levels were similar in all *** data suggest that under non-stressful physical condition,the ANT1-de-cient muscle cells were in the same mitochondrial state as WT ones and that the signi-cant difference in the mitochondrial redox state between quadriceps and hearts found in WT might be diminished in ANT1-de-cient *** imaging of muscles under physical stress can be conducted in future.

关键词： ANT1 redox ratio flavoproteins