Quantum mechanical/molecular mechanical studies on spectral tuning mechanisms of visual pigments and other photoactive proteins.

abstract：:Eumelanin plays a variety of important physiological roles in human skin. However, its structure and fundamental properties still remain poorly understood. Although the absorbance of eumelanin is broad and reveals little about its structure, a variety of techniques have revealed the presence of a disordered array of c...

journal_title：Photochemistry and photobiology

authors： Nighswander-Rempel SP,Mahadevan IB,Rubinsztein-Dunlop H,Meredith P

更新日期：2007-11-01 00:00:00

abstract：:SV40 DNA was irradiated in vitro and in vivo with UV-C (240-280 nm) and UV-B (280-320 nm) light, and damaged sites sensitive to digestion with Escherichia coli endonuclease III (endo III) and bacteriophage T4 endonuclease V (endo V) were quantified. The frequency of endo III-sensitive sites (primarily cytosine photohy...

journal_title：Photochemistry and photobiology

authors： Mitchell DL,Jen J,Cleaver JE

更新日期：1991-11-01 00:00:00

abstract：:Photochemo and photodynamic therapies are minimally invasive approaches for the treatment of cancers and powerful weapons for competing bacterial resistance to antibiotics. Synthetic and naturally occurring quinazolinones are considered privileged anticancer and antibacterial agents, with several of them to have emerg...

journal_title：Photochemistry and photobiology

authors： Panagopoulos A,Balalas T,Mitrakas A,Vrazas V,Katsani KR,Koumbis AE,Koukourakis MI,Litinas KE,Fylaktakidou KC

更新日期：2021-01-01 00:00:00

abstract：:In this study our aim was to determine the biophysical values of constitutive skin color in Caucasians and to define the correlation between skin color and phototype assessed according to the Fitzpatrick method. Constitutive skin color was measured on the buttock, with a Minolta CR-200 colorimeter, in a population-of ...

journal_title：Photochemistry and photobiology

authors： Rubegni P,Cevenini G,Flori ML,Fimiani M,Stanghellini E,Molinu A,Barbini P,Andreassi L

更新日期：1997-02-01 00:00:00

abstract：:The design, synthesis and application of a new fluorescent-labeling reagent for collagen has been developed as a prerequisite for the design of a photoactivated collagen-crosslinking compound for surgical wound closure. The amine groups in collagen are the targets of a rational design for a new fluorophore because nat...

journal_title：Photochemistry and photobiology

authors： Timberlake GT,Reddy GK,Stehno-Bittel L,Weber JF,Amslinger S,Givens RS

更新日期：2002-11-01 00:00:00

abstract：:The effect of netropsin on the oxidative reactions of duplex DNA was examined. One-electron oxidation of DNA creates a radical cation that migrates through duplex DNA and reacts primarily at GG steps. Netropsin is a dication that specifically binds primarily by hydrogen bonding in the minor groove at sites that have f...

journal_title：Photochemistry and photobiology

authors： Roberts LW,Schuster GB

更新日期：2004-11-01 00:00:00

abstract：:The individual tryptophanyl contributions to the near-ultraviolet dichroic activity of apomyoglobin in its native conformation have been resolved. This was accomplished by comparing the spectra of two classes of apomyoglobin with different aromatic residue contents and observing the effect of a specific modification o...

journal_title：Photochemistry and photobiology

authors： Sirangelo I,Irace G,Bismuto E

更新日期：1994-06-01 00:00:00

abstract：:The photostability of drugs administered topically on unprotected skin is a complex phenomenon that could be connected with the loss of activity or, rather rarely, the occurrence of toxic degradation products. In this study, an in-depth investigation of the photostability of terbinafine, in both solutions and formulat...

journal_title：Photochemistry and photobiology

authors： Kryczyk-Poprawa A,Żmudzki P,Koczurkiewicz P,Pękala E,Hubicka U

更新日期：2019-07-01 00:00:00

abstract：:A visual chromophore analogue, 10-methyl-13-demethyl (dm) retinal, was synthesized and reconstituted with bleached bovine rhodopsin to form a visual pigment derivative with absorbance maximum at 505 nm. The investigations with this new compound were stimulated from recent results using 13-dm retinal as a chromophore t...

journal_title：Photochemistry and photobiology

authors： Koch D,Gärtner W

更新日期：1997-01-01 00:00:00

abstract：:The total ozone column (TOC) is the most significant quantity for estimating the erythemally effective UV radiation under clear sky conditions. Uncertainties in TOC measurements and a limited spatial and temporal resolution therefore influence the quality of calculated erythemally effective radiation. The UV Index, th...

journal_title：Photochemistry and photobiology

authors： Schmalwieser AW,Erbertseder T,Schauberger G,Weihs P

更新日期：2008-09-01 00:00:00

abstract：:Endogenous reduced nicotinamide adenine dinucleotide (NADH) fluorescence provides an intrinsic indicator of the cellular metabolic state, but prolonged monitoring is limited by photobleaching and/or phototoxicity. Multiphoton excitation of NADH by ultrashort, 740-nm laser pulses provides a significant improvement over...

journal_title：Photochemistry and photobiology

authors： Tiede LM,Nichols MG

更新日期：2006-05-01 00:00:00

abstract：:A spectral resolution procedure was used to resolve the absorption, excitation and emission spectra of the fluorescein monoanion in a number of solvent-water mixtures. This permitted an analysis of the effect of the solvent environment on the spectral properties of the monoanion and on the lactone/monoanion/dianion tr...

journal_title：Photochemistry and photobiology

authors： Klonis N,Sawyer WH

更新日期：2000-08-01 00:00:00

abstract：:Carp (Cyprinus carpio) were repeatedly exposed to 0, 60, 120 and 240 mJ/cm2 ultraviolet B (UVB) radiation three times in 1 week (short-term exposure) or 12 times in 4 weeks (long-term exposure). The effect of UVB on the functioning of the carp immune system was studied on day 2 after the final irradiation. After short...

journal_title：Photochemistry and photobiology

authors： Markkula SE,Salo HM,Immonen AK,Jokinen EI

更新日期：2005-05-01 00:00:00

abstract：:In this issue, we offer a symposium-in-print that is focused on several new advancements in fundamental research related to the family of GFP (green fluorescent protein)-like proteins. A few applied aspects are also included to illustrate the impact this amazing set of colored proteins has made on our understanding of...

journal_title：Photochemistry and photobiology

authors： Wachter RM

更新日期：2006-03-01 00:00:00

abstract：:Pheophorbide a-induced photo-oxidation, in vitro, of cytochrome c oxidase and cytochrome c results in irreversible modifications to both protein components. Photo-oxidation of cytochrome c, as exhibited by change in its heme oxidation state, displays exponential kinetics and is detected with a lag period. Both the pho...

journal_title：Photochemistry and photobiology

authors： Chernomorsky S,Wong C,Poretz RD

更新日期：1992-02-01 00:00:00

abstract：:The tetraruthenated porphyrin, mu-[meso-5,10,15,20-tetra(pyridyl)porphyrin]tetrakis[bis-(bipyridine) chloride ruthenium(II)] (TRP) is a supramolecular cationic species. The aim of the present investigation was to evaluate the photodynamic properties of TRP and Zn-TRP to damage DNA with emphasis on the mechanistic aspe...

journal_title：Photochemistry and photobiology

authors： Ravanat JL,Cadet J,Araki K,Toma HE,Medeiros MH,Mascio PD

更新日期：1998-11-01 00:00:00

abstract：:A concept has been presented whereby X-ray irradiation can be used to induce visible luminescence of chromophores such as porphyrins. The essential aspects of the idea have been demonstrated in a supramolecular assembly consisting of a water-dispersed polystyrene latex with an embedded scintillating compound, 2,5-diph...

journal_title：Photochemistry and photobiology

authors： Kokotov S,Lewis A,Neumann R,Amrusi S

更新日期：1994-03-01 00:00:00

abstract：:As the most important interface between human body and external environment, skin acts as an essential barrier preventing various environmental damages, among which DNA-damaging UV radiation from the sun remains the major environmental risk factor causing various skin diseases. It has been well documented that wavelen...

journal_title：Photochemistry and photobiology

authors： Liu H,Yue J,Lei Q,Gou X,Chen SY,He YY,Wu X

更新日期：2015-07-01 00:00:00

abstract：:In this study, water-soaked seeds of sunflower were exposed to He-Ne laser irradiation of different energies to determine whether or not He-Ne laser irradiation caused changes to seed thermodynamic and germination parameters as well as effects on the activities of germination enzymes. The experiment comprised four ene...

journal_title：Photochemistry and photobiology

authors： Perveen R,Ali Q,Ashraf M,Al-Qurainy F,Jamil Y,Raza Ahmad M

更新日期：2010-09-01 00:00:00

abstract：:The activity of the bimodal fluorescent protein (bmFP) (lambda max, 488 and 517 nm) in the in vitro luciferase reaction has been studied. The bmFP that is produced by Photobacterium phosphoreum strain bmFP is a dimer of two homologous subunits binding four riboflavin 5'-phosphate (FMN)-myristate chromophores. The addi...

journal_title：Photochemistry and photobiology

authors： Karatani H,Konaka T

更新日期：2000-02-01 00:00:00

abstract：:The photodynamic therapy (PDT) activity of the bis(dimethylthexylsiloxy)silicon 2,3-naphthalocyanine (SiNc 8) was evaluated against the EMT-6 tumor implanted intradermally in BALB/c mice. The SiNc 8 was formulated in aqueous emulsions based on Cremophor EL or Solutol HS 15. The formulation was shown to affect plasma c...

journal_title：Photochemistry and photobiology

authors： Brasseur N,Ouellet R,Lewis K,Potter WR,van Lier JE

更新日期：1995-12-01 00:00:00

abstract：:Intermolecular interactions of human serum proteins with a hydrophilic nonmetalloporphyrin, 13,17-bis(1-carboxypropionyl)carbomoylethyl-8-ethenyl-2-hydroxy-3-hydroxyiminoethylidene-2,7,12,18-tetramethylporphyrin sodium salt (ATX-S10 (Na)), or a hydrophilic gallium-metalloporphyrin, diethylenetriamine pentaacetic acid ...

journal_title：Photochemistry and photobiology

authors： Yamaguchi M,Tanabe S,Nakajima S,Takemura T,Ogita K,Kuwayama H,Sakata I,Miyaki S,Suzuki K,Namiki H,Uzuka Y,Sarashina T

更新日期：2004-09-01 00:00:00

abstract：:Photodynamic therapy (PDT), carried out at low fluence rates, may enhance tumor response as well as affect treatment selectivity. We have studied the effects of fluence rate on the response of the murine radiation-induced fibrosarcoma (RIF) to PDT using Photofrin (5 mg/kg). Tumor response was tested over a large range...

journal_title：Photochemistry and photobiology

authors： Sitnik TM,Henderson BW

更新日期：1998-04-01 00:00:00

abstract：:Immunosuppressive doses of solar-simulated UV radiation activate lymph node B cells that can suppress primary immunity by inhibiting the function of dendritic cells. The aim of this study was to determine the waveband responsible for activation of these suppressor B cells. We exposed C57BL/6 mice to various doses of e...

journal_title：Photochemistry and photobiology

authors： Byrne SN,Ahmed J,Halliday GM

更新日期：2005-11-01 00:00:00

abstract：:When Escherichia coli cells were irradiated by UVA in the presence of 6-mercaptopurine (6-MP) or 2-thiouracil (S2Ura), two kinds of repair-deficient strains of recA- and uvrA- were killed more efficiently than the parental wild-type strain having normal repair capacities. In addition, these agents with UVA exposure gr...

journal_title：Photochemistry and photobiology

authors： Komeda K,Iwamoto S,Kominami S,Ohnishi T

更新日期：1997-01-01 00:00:00

abstract：:Biophysical and photobiological properties of a group of bacteriochlorins were compared with efficacy of these products for photodynamic therapy of murine tumors. Predictive factors for selective photosensitization in vivo include affinity binding to lipoproteins greater than albumin, extinction coefficient at the wav...

journal_title：Photochemistry and photobiology

authors： Kessel D,Smith KM,Pandey RK,Shiau FY,Henderson B

更新日期：1993-08-01 00:00:00

abstract：:The reactions of polyuridylic acid [poly(U)] with Ru(bpy)3(3+) [Ru(III)] and SO4.-, following UV and visible light irradiation of Ru(bpy)3(2+) [Ru(II)] in the presence of S2O8(2-), were studied in an argon-saturated aqueous solution using time-resolved absorption and conductivity methods. The kinetics of the Ru(III) c...

journal_title：Photochemistry and photobiology

authors： Tossi AB,Görner H,Schulte-Frohlinde D

更新日期：1989-11-01 00:00:00

abstract：:Although the first reactive oxygen species (ROS) formed during irradiation of photosensitized cells is almost invariably singlet molecular oxygen (1O2), other ROS have been implicated in the phototoxic effects of photodynamic therapy (PDT). Among these are superoxide anion radical (*O2(-)), hydrogen peroxide (H2O2) an...

journal_title：Photochemistry and photobiology

authors： Price M,Terlecky SR,Kessel D

更新日期：2009-11-01 00:00:00

abstract：:The fluorescent pH probe carboxy-seminaphtorhodafluor-1 (C-Snarf-1) has been used for laser microspectro-fluorometric assays of intracellular pH in 3T3 mouse fibroblasts treated with hypocrellin A. These results are compared to those previously obtained with the structurally related hydroxylated polycyclic quinone, hy...

journal_title：Photochemistry and photobiology

authors： Chaloupka R,Sureau F,Kocisova E,Petrich JW

更新日期：1998-07-01 00:00:00

abstract：:Use of near infrared instead of visible light would markedly improve tissue penetration, making larger tumors candidates for photochemotherapy. Because common photesensitizers exhibit virtually no absorption in this wavelength region, conditions are required where the simultaneous action of two photons is possible. He...

journal_title：Photochemistry and photobiology

authors： Lenz P

更新日期：1995-08-01 00:00:00