Radical cation generation from singlet and triplet excited states of all-trans-lycopene in chloroform.

abstract：:In cultured human keratinocytes, the tumor suppressor p53 acts as a control element in the protective response to UVB radiation and is affected by a variety of factors linked to cellular adhesion and differentiation. Because keratinocytes within the epidermis are not a homogeneous population but differ in their prolif...

journal_title：Photochemistry and photobiology

authors： Will K,Neben M,Schmidt-Rose T,Deppert W,Wittern KP,Bergemann J

更新日期：2000-03-01 00:00:00

abstract：:The proton channels of the bacteriorhodopsin (BR) proton pump contain bound water molecules. The channels connect the purple membrane surfaces with the protonated retinal Schiff base at the membrane center. Films of purple membrane equilibrated at low relative humidity display a shift of the 570 nm retinal absorbance ...

journal_title：Photochemistry and photobiology

authors： Renthal R,Gracia N,Regalado R

更新日期：2000-11-01 00:00:00

abstract：:Cultured cells accumulate acridine orange (AO), which is a weak basic dye and a photosensitizer, in lysosomes and other acidic compartments. During exposure to blue light, AO-loaded macrophages show decreasing red granular fluorescence and increasing green diffuse fluorescence. This is hypothesized to represent peroxi...

journal_title：Photochemistry and photobiology

authors： Zdolsek JM,Olsson GM,Brunk UT

更新日期：1990-01-01 00:00:00

abstract：:Self-aggregation of naturally occurring bacteriochlorophyll (BChl)-e in nonpolar organic solvents was investigated by visible absorption, fluorescence emission and circular dichroism spectra. Cultured brown-colored photosynthetic bacteria have several BChl-e as light-harvesting antenna pigments. Three major BChl-e hom...

journal_title：Photochemistry and photobiology

authors： Saga Y,Matsuura K,Tamiaki H

更新日期：2001-07-01 00:00:00

abstract：:Evidence is mounting that UV-B and UV-A radiation affect skin differently in responses as diverse as erythema and elastosis. We found in this study that collagen metabolism was also differentially affected. Albino hairless mice were irradiated with two UV-A sources: (1) UVASUN 3000 (340-400 nm) for cumulative exposure...

journal_title：Photochemistry and photobiology

authors： Kligman LH,Gebre M

更新日期：1991-08-01 00:00:00

abstract：:Generating accurate population-specific public health messages regarding sun protection requires knowledge about seasonal variation in sun exposure in different environments. To address this issue for a subtropical area of Australia, we used polysulphone badges to measure UVR for the township of Nambour (26 degrees la...

journal_title：Photochemistry and photobiology

authors： Neale RE,Hamilton AR,Janda M,Gies P,Green AC

更新日期：2010-03-01 00:00:00

abstract：:Protoporphyrin IX dimethyl ester (PME), a dimethyl esterification of protoporphyrin IX (PpIX), exhibits higher intracellular uptake into NPC/CNE2 cells, a poorly differentiated human nasopharyngeal carcinoma, than does PpIX. Phototoxicity studies reveal PME to be a more potent photosensitizer than is PpIX, at the earl...

journal_title：Photochemistry and photobiology

authors： Yee KK,Soo KC,Bay BH,Olivo M

更新日期：2002-12-01 00:00:00

abstract：:In clinical 5-aminolevulinic acid (ALA)-based photodynamic therapy (PDT) of skin tumors it is desirable to develop vehicles that minimize the penetration of ALA through normal stratum corneum and maximize it through the compromised stratum corneum of the tumors to improve tumor selectivity. We have designed a bioadhes...

journal_title：Photochemistry and photobiology

authors： Donnelly RF,Ma LW,Juzenas P,Iani V,McCarron PA,Woolfson AD,Moan J

更新日期：2006-05-01 00:00:00

abstract：:Copper(II), in the presence of UV-B radiation (280-315 nm), can generate single-strand breaks in the sugar-phosphate backbone of pBR322 plasmid DNA. A low level of single-strand backbone breaks occurs in the presence of Cu(II) alone, but UV-B irradiation increases the rate by the more than 100-fold. Concomitant with t...

journal_title：Photochemistry and photobiology

authors： Lloyd RE,Larson RA,Adair TL,Tuveson RW

更新日期：1993-06-01 00:00:00

abstract：:Previous studies with methylene blue (MB) in red cell suspensions have demonstrated that extracellular, but not intracellular, virus can be readily photoinactivated. To test if the resistance of intracellular virus to inactivation is related to the permanent positive charge of the phenothiazine, a series of uncharged ...

journal_title：Photochemistry and photobiology

authors： Skripchenko A,Robinette D,Wagner SJ

更新日期：1997-03-01 00:00:00

abstract：:Photodynamic therapy (PDT) using the second-generation photosensitizer phthalocyanine (Pc) 4 causes mitochondrial damage and induces apoptosis through the release of cytochrome c to the cytosol. Another protein of the mitochondrial intermembrane space, Smac/DIABLO (second mitochondria-derived activator of caspase/dire...

journal_title：Photochemistry and photobiology

authors： Usuda J,Chiu SM,Azizuddin K,Xue LY,Lam M,Nieminen AL,Oleinick NL

更新日期：2002-08-01 00:00:00

abstract：:The broad-band normal incidence UVB beam radiation has been measured at Neve Zohar, Dead Sea basin, using a prototype tracking instrument composed of a Model 501A UV-Biometer mounted on an Eppley Solar Tracker Model St-1. The diffuse and beam fraction of the solar global UVB radiation have been determined using the co...

journal_title：Photochemistry and photobiology

authors： Kudish AI,Harari M,Evseev EG

更新日期：2011-01-01 00:00:00

abstract：:We examined the influence of solar ultraviolet-B radiation (UV-B; 280-320 nm) on the growth, biomass production and phenylpropanoid concentrations of Deschampsia antarctica during the springtime ozone depletion season at Palmer Station, along the Antarctic Peninsula. Treatments involved placing filters on frames over ...

journal_title：Photochemistry and photobiology

authors： Ruhland CT,Xiong FS,Clark WD,Day TA

更新日期：2005-09-01 00:00:00

abstract：:We developed a novel method for the isolation of the PSI-LHCI-LHCII complex from spinach leaves. The supercomplex was resolved into a core complex (CPI), LHCII trimers, LHCI dimers and LHCII monomers using green gel electrophoresis. We then investigate changes in the fluorescence and absorption spectra of PSI-LHCI-LHC...

journal_title：Photochemistry and photobiology

authors： Qin X,Wang W,Wang K,Xin Y,Kuang T

更新日期：2011-01-01 00:00:00

abstract：:The pyrimidine nucleobases contained in DNA undergo a variety of photoinduced reactions in which two moieties become joined to form a product (e.g. formation of cyclobutane dimers and [6-4] adducts). Herein, we describe a new type of photoconjugation reaction that has been shown to occur for 5-methylcytosine (5-MeC), ...

journal_title：Photochemistry and photobiology

authors： Shetlar MD,Chung J

更新日期：2012-03-01 00:00:00

abstract：:The phototoxic effects of demethylchlortetracycline (DMCT) with UVA radiation on isolated rat liver mitochondria were studied. DMCT at concentration of 21.5 microM with 5.53 x 10(-2) J cm-3 of UVA was found to be a potent uncoupler of oxidative phosphorylation. DMCT alone also uncoupled mitochondria but at higher conc...

journal_title：Photochemistry and photobiology

authors： Takagi S,Mizuno N,Adachi K,Wakabayashi T

更新日期：1990-02-01 00:00:00

abstract：:The fluoroquinolone (FQ) antibiotics photosensitize human skin to solar UV radiation and are reported to photosensitize tumor formation in mouse skin. As tumor initiation will not occur without genotoxic insult, we examined the potential of ciprofloxacin, lomefloxacin, fleroxacin, BAYy3118 (a recently developed monofl...

journal_title：Photochemistry and photobiology

authors： Reavy HJ,Traynor NJ,Gibbs NK

更新日期：1997-09-01 00:00:00

abstract：:Channel and pump rhodopsins use energy from light absorbed by a covalently bound retinal chromophore to transport ions across membranes of microbial cells. Ion transfer steps, including proton transfer, can couple to changes in protein conformational dynamics and water positions. Although general principles of how mic...

journal_title：Photochemistry and photobiology

authors： Bondar AN,Smith JC

更新日期：2017-11-01 00:00:00

abstract：:We examined the effects of daily exposure to UVB on growth, reproduction and histological characteristics of Daphnia magna over two generations at 20, 22, 25 and 30°C. Animals were exposed to 16 h of UVA and photosynthetically active radiation daily. Treated animals received 6 h of UVB during the light phase. Parental...

journal_title：Photochemistry and photobiology

authors： Huebner JD,Loadman NL,Wiegand MD,Huebner E,Palitsky DJ,Husarewycz WH

更新日期：2013-01-01 00:00:00

abstract：:The pharmacokinetics of Zn phthalocyanine (ZnPc) encapsulated in dipalmitoyl-phosphatidylcholine (DPPC) liposomes, injected intravenously in Skh:HR-1 nude mice, was monitored by two in vitro techniques and one in vivo technique, all based on fluorescence spectroscopy. The in vitro methods involve either fluorescence m...

journal_title：Photochemistry and photobiology

authors： Biolo R,Jori G,Kennedy JC,Nadeau P,Pottier R,Reddi E,Weagle G

更新日期：1991-01-01 00:00:00

abstract：:Plant responses to light spectral quality can be exploited to deliver a range of agronomically desirable end points in protected crops. This can be achieved using plastics with specific spectral properties as crop covers. We have studied the responses of a range of crops to plastics that have either (a) increased tran...

journal_title：Photochemistry and photobiology

authors： Paul ND,Jacobson RJ,Taylor A,Wargent JJ,Moore JP

更新日期：2005-09-01 00:00:00

abstract：:The thermodynamic parameters for the formation of the free radicals upon electron transfer quenching of the flavin triplet state (3FMN) by tryptophan and tyrosine, Delta(FR)H and Delta(FR)V, were obtained in aqueous solution by the application of laser-induced optoacoustic spectroscopy at various temperatures. The Del...

journal_title：Photochemistry and photobiology

authors： Crovetto L,Martínez-Junza V,Braslavsky SE

更新日期：2006-01-01 00:00:00

abstract：:Tetraarylporphyrins substituted with nitro groups at beta-pyrrolic positions are potential candidates for electron-accepting pigments in model systems for photosynthesis. The photophysics of 2-nitro-5,10,15,20-tetra-p-tolylporphyrin and its zinc analog have been studied in order to evaluate this potential. The ground ...

journal_title：Photochemistry and photobiology

authors： Gust D,Moore TA,Luttrull DK,Seely GR,Bittersmann E,Bensasson RV,Rougée M,Land EJ,De Schryver FC,Van der Auweraer M

更新日期：1990-04-01 00:00:00

abstract：:We report here the design and synthesis of porphyrin-metallocene dyads consisting of a metallocene [either ferrocene or mixed sandwich η(5)-[C5H4(COOH)]Co(η(4)-C4Ph4) connected via an ester linkage at meso phenyl position of either free-base or zinc porphyrin. All these dyad systems were characterized by various spect...

journal_title：Photochemistry and photobiology

authors： Gokulnath S,Achary BS,Kumar CK,Trivedi R,Sridhar B,Giribabu L

更新日期：2015-01-01 00:00:00

abstract：:Central venous catheters (CVC) are widely used in the United States and are associated with 250,000 to 500,000 CVC-related infections in hospitals annually. We used a catheter made from ultraviolet-C (UVC) transmissive material to test whether delivery of UVC from the lumen would allow inactivation of microorganisms o...

journal_title：Photochemistry and photobiology

authors： Dai T,Tegos GP,St Denis TG,Anderson D,Sinofsky E,Hamblin MR

更新日期：2011-01-01 00:00:00

abstract：:Skin cancer studies depend on questionnaires to estimate exposure to ultraviolet light and subsequent risk but are limited by recall bias. We investigate the feasibility of developing a short checklist of categories comprising outdoor activities that can improve sun exposure questionnaires for use in epidemiologic stu...

journal_title：Photochemistry and photobiology

authors： Kwok RK,Linet MS,Chodick G,Kleinerman RA,Freedman DM,Fears T,Johnson RE,Alexander BH

更新日期：2009-01-01 00:00:00

abstract：:The in vivo pharmacokinetics of protoporphyrin IX (PpIX) after administration of 5-aminolevulinic acid (ALA) cannot be described accurately by mathematical models using first-order rate processes. We have replaced first-order reaction rates by dose-dependent (Michaelis-Menten [MM]) reaction rates in a mathematical com...

journal_title：Photochemistry and photobiology

authors： Aalders MC,van der Vange N,Star WM,Sterenborg HJ

更新日期：2001-08-01 00:00:00

abstract：:Low-power lasers are commonly used in human medicine for treatment of various pathological conditions, but mechanisms of their healing effects are still poorly understood. The results of this study provide information related to these effects at the cellular level. Two different protozoan species, Euglena gracilis and...

journal_title：Photochemistry and photobiology

authors： Koutna M,Janisch R,Unucka M,Svobodnik A,Mornstein V

更新日期：2004-11-01 00:00:00

abstract：:A model of UV-induced DNA damage in oceanic bacterioplankton was developed and tested against previously published and novel measurements of cyclobutane pyrimidine dimers (CPD) in surface layers of the ocean. The model describes the effects of solar irradiance, wind-forced mixing of bacterioplankton and optical proper...

journal_title：Photochemistry and photobiology

authors： Huot Y,Jeffrey WH,Davis RF,Cullen JJ

更新日期：2000-07-01 00:00:00

abstract：:Photodamage to the endoplasmic reticulum (ER) can initiate a death pathway termed paraptosis. The "canonical" model of paraptosis, initiated by certain drugs and other stimuli, requires a brief interval of protein synthesis, involves the action of MAP kinases and can be followed by biochemical markers. The latter incl...

journal_title：Photochemistry and photobiology

authors： Kessel D

更新日期：2020-09-01 00:00:00