DNA Damage Induced by Late Spring Sunlight in Antarctica
ABSTRACTSunlight ultraviolet (UV) radiation constitutes an important environmental genotoxic agent that organisms are exposed to, as it can damage DNA directly, generating pyrimidine dimers, and indirectly, generating oxidized bases and single ‐strand breaks (SSBs). These lesions can lead to mutations, triggering skin and eye disorders, including carcinogenesis and photoaging. Stratospheric ozone layer depletion, particularly in the Antarctic continent, predicts an uncertain scenario of UV incidence on the Earth in the next decades. Thi s research evaluates the DNA damage caused by environmental exposure to late spring s...
Source: Photochemistry and Photobiology - July 2, 2020 Category: Science Authors: Fabiana Fuentes ‐León, Andressa Peres de Oliveira, Nathalia Quintero‐Ruiz, Veridiana Munford, Gustavo Satoru Kajitani, Antonio Coimbra Brum, André Passaglia Schuch, Pio Colepicolo, Angel Sánchez‐Lamar, Carlos Frederico Martins Menck Tags: RESEARCH ARTICLE Source Type: research

Hypericin Accumulation as a Determinant of PDT Efficacy
AbstractEfficacy of photodynamic therapy (PDT) with hypericin was compared using two cell lines in monolayer culture. Photokilling was substantially impaired in the A549 (human ‐derived lung tumor) when compared with the 1c1c7 murine hepatoma. The efficacy of PDT with regard to photokilling was correlated with the steady‐state intracellular hypericin concentration. There was otherwise no difference in subcellular targets or the pathway to cell death: paraptosis. In a p rior study involving cell lines derived from patients with head and neck cancer, differences in response to PDT had shown no correlation with photosensi...
Source: Photochemistry and Photobiology - June 29, 2020 Category: Science Authors: David Kessel Tags: RESEARCH NOTE Source Type: research

A Sharp Jump in Photocatalytic Activity of Elemental Sulfur for Dye Degradation in Alkaline Solution
In this study, we report a low ‐cost and fast method for the degradation of methyl violet in water under visible light and also sunlight by using elemental sulfur (S8). The results show that sulfur is a good photocatalyst which operates under visible light and can be utilized for degradation of methyl violet. The photocatalytic degradation of methyl violet in acidic, neutral and alkaline media was investigated and it was found that the photocatalytic efficiency increases dramatically in alkaline solution. The effects of the initial concentration of the dye, photocatalyst dosage, solution pH and photocatalyst reusability ...
Source: Photochemistry and Photobiology - June 25, 2020 Category: Science Authors: Vahideh Alvandi Peyman, Saeid Azizian Tags: RESEARCH ARTICLE Source Type: research

Photodynamic Therapy and Immune Checkpoint Blockade
ABSTRACTImmune checkpoints including PD ‐1 and CTLA‐4 help to regulate the intensity and timeframe of the immune response. Since they become upregulated in cancer and prevent sufficient anti‐tumor immunity, monoclonal antibodies against these checkpoints have shown clinical promise for a range of cancers. Multimodal treatment plans combining immune checkpoint inhibitors with other therapies, including photodynamic therapy (PDT), may help to expand treatment efficacy and minimize side effects. PDT’s cytotoxic effects are spatially limited by the light activation process, constraining PDT direct effects to the tr...
Source: Photochemistry and Photobiology - June 23, 2020 Category: Science Authors: Gwendolyn M. Cramer, Edmund K. Moon, Keith A. Cengel, Theresa M. Busch Tags: SPECIAL ISSUE INVITED REVIEW Source Type: research

A Photoprotective Effect by Cation ‐π‐Interaction? Quenching of Singlet Oxygen by an Indole Cation‐π Model System
The cation ‐π interaction between a sodium cation and an indole moiety significantly decreases the total rate of removal of singlet oxygen (kT) in an indole ‐crown model system. A type I photooxidation of the indole group is also inhibited by the cation‐π interaction. These results imply that there may be a photoprotective effect by the cation‐π interaction for tryptophan. AbstractWe investigated the effect of the cation ‐π interaction on the susceptibility of a tryptophan model system toward interaction with singlet oxygen, that is, type II photooxidation. The model system consists of two indole unit...
Source: Photochemistry and Photobiology - June 20, 2020 Category: Science Authors: Gary E. Arevalo, David A. Cagan, Charlotte G. Monsour, Arman C. Garcia, Alison McCurdy, Matthias Selke Tags: Research Article Source Type: research

TiO2 Photocatalyzed Degradation of the Azo Dye Disperse Red 1 in Aqueous Micellar Environments
AbstractThe photoinduced degradation of the azo dye disperse red 1 was studied in a microheterogeneous system comprising titanium oxide (TiO2) and sodium dodecylsulfate, exposed to UV light. Degussa P25, Anatase and TiO2 synthesized in acidic conditions were supported on raschig rings. The TiO2 photocatalyzed degradation is enhanced in the vicinity of the surfactant critical micelle value. Further increase on the surfactant concentration lead to a loss in photodegradation performance up to values equivalent to that observed without surfactant. Surfactant influence can be explained by two different phenomena taking place. T...
Source: Photochemistry and Photobiology - June 19, 2020 Category: Science Authors: Eduardo Pino, Cristian Calder ón, Piero Castro Tags: SPECIAL ISSUE RESEARCH ARTICLE Source Type: research

Characterization of a Bio ‐sourced, Fluorescent, Ratiometric pH Indicator with Alkaline pKa
We report the characterization of a pH ‐responsive fluorophore from an endophytic fungus isolated from sand pine. The endogenous fluorescence of the live organism was measured using fluorescence microscopy. Computational interpretation of the spectra was accomplished with time‐dependent density functional‐theory methods. The combin ed use of experimental and theoretically predicted spectra revealed the pH equilibria and photo‐excited tautomerization of the natural product, 5‐methylmellein. This product shows promise both as a stand‐alone pH‐indicating fluorophore, with alkaline pKa, and as "green" f...
Source: Photochemistry and Photobiology - June 19, 2020 Category: Science Authors: Samar Alheety, Domenic Valenti, Nirvani Mujumdar, Nakita Ellis, Andres D. Campiglia, James K. Harper, Emily C. Heider Tags: RESEARCH ARTICLE Source Type: research

Continuous Flow Reactor for The Controlled Synthesis and Inline Photocatalysis of Antibacterial Ag2S Nanoparticles
AbstractThe present study is focused on the integration of microreactors to synthesize visible ‐light active nano‐photocatalysts for inline photocatalytic degradation of organic dye and antibacterial activity. A wire assisted and a rapid laser micromachining technique have been employed for the fabrication of polydimethylsiloxane (PDMS) and poly(methyl methacrylate) (PMMA) based microreac tors respectively. By varying the design and chemical reagents involved, different sizes of visible light active Ag2S nanoparticles were prepared via a continuous microfluidics approach using fabricated microreactors. When polyvinylpy...
Source: Photochemistry and Photobiology - June 14, 2020 Category: Science Authors: Bhanu Prakash, Vibhav Katoch, Asmita Shah, Manju Sharma, M. Manolata Devi, Jiban J Panda, Jadab Sharma, Ashok Kumar Ganguli Tags: RESEARCH ARTICLE Source Type: research

Effect of Nail Thickness on Visible Radiation Transmittance: Implications for New Photodynamic Therapy Technologies in Onychomycosis
AbstractPhotodynamic therapy is taking importance as a non ‐intrusive treatment for nail onychomycosis. Knowledge of true transmittance values across nails could lead to qualitative and quantitative improvements in light‐based treatments. We have characterized the spectral transmittance of healthy and fungally infected human finger nails and toenails ac cording to nail thickness and we propose a surface transmittance model for the small‐scale optimization of light‐based treatments. Transmittance of finger nails and toe nails was analyzed by means of spectroradiometric measurements under solar simulated visible ligh...
Source: Photochemistry and Photobiology - June 13, 2020 Category: Science Authors: Enrique Navarrete de G álvez, José Aguilera, María Victoria de Gálvez, Pablo Fonda‐Pascual, Enrique Herrera‐Ceballos, Alfonso Gago‐Calderón Tags: RESEARCH ARTICLE Source Type: research

Rational Design, Synthesis and Evaluation of Indole Nitrogen Hybrids as Photosystem II Inhibitors
In this study, 6 ‐Chloro‐8‐nitro‐2,3,4,9‐tetrahydro‐1H‐carbazole (15a) and 5 ‐chloro‐2,3‐dimethyl‐7‐nitro‐1H‐indole (15b) showed the best results by reducing the phenomenological parameters of reaction centres ABS/RC, TR0/RC and ET0/RC of PSII. Electron chain blockage by these compounds may lead to diminished ATP synthesis and CO2 fixation which interrupt the plant development. The compounds15a and15b both act as post ‐emergent herbicides, reducing the dry biomass ofIpomoea grandifolia andSenna alata weeds average of 40% and 37%, respectively, corroborating the fluorescence results. Additional...
Source: Photochemistry and Photobiology - June 13, 2020 Category: Science Authors: J éssica Maria de Souza, Bruno Rodrigues Fazolo, Jhully Wellen Ferreira Lacerda, Mariana de Souza Moura, Arielly Celestino Rodrigues dos Santos, Leonardo Gomes de Vasconcelos, Paulo Teixeira de Sousa Junior, Evandro Luiz Dall’Oglio, Akbar Ali, Tags: RESEARCH ARTICLE Source Type: research

Issue Information
Photochemistry and Photobiology, Volume 96, Issue 3, Page 451-452, May/June 2020. (Source: Photochemistry and Photobiology)
Source: Photochemistry and Photobiology - June 12, 2020 Category: Science Tags: Issue Information Source Type: research

Preface: Memorial Issue Dedicated to Thomas J. Dougherty
Photochemistry and Photobiology, Volume 96, Issue 3, Page 453-453, May/June 2020. (Source: Photochemistry and Photobiology)
Source: Photochemistry and Photobiology - June 12, 2020 Category: Science Authors: Tayyaba Hasan, David Kessel, Alexander Greer Tags: Editorial Source Type: research

Harmless Effects of Sterilizing 222 ‐nm far‐UV Radiation on Mouse Skin and Eye Tissues
AbstractThere is growing interest in using ultraviolet (UV) radiation for bactericidal and viral decontamination of air, surfaces and foods, a trend that is reinforced during the Covid ‐19 pandemic. For almost a century and a half, UVC and UVB radiations have been used extensively for non‐thermal sterilization against various microbial pathogens by developing so‐called ultraviolet germicidal irradiation (UVGI) disinfection treatments (1). Most previous applications have used UVC light emitted from broad spectrum 254‐nm low‐pressure mercury lamps, which, however, has undesirable, harmful effects on the skin and re...
Source: Photochemistry and Photobiology - June 11, 2020 Category: Science Authors: Jean Cadet Tags: HIGHLIGHT ARTICLE (INVITED) Source Type: research

Azobenzene Photoswitch for Isomerization ‐Dependent Cancer Therapy via Azo‐Combretastatin A4 and Phototrexate
ABSTRACTThe adverse effects of chemotherapeutic drugs to healthy organs/cells greatly limit their clinical efficacy and patient compliance. The unique behavior of azobenzene photoswitch offers a remarkable tool to address the side effects of chemotherapeutic drugs. The azobenzene moiety has been integrated within some chemodrugs to realize photo ‐triggered activation of drug cytotoxicity. However, the clinical translation of these agents has been facing a few barriers. In this article, we present our viewpoints on potential solutions to address the following challenges associated with azobenzene‐based photoswitchable c...
Source: Photochemistry and Photobiology - June 10, 2020 Category: Science Authors: Di Naer Mulatihan, Tao Guo, Yanjun Zhao Tags: INVITED REVIEW Source Type: research

Estimated Inactivation of Coronaviruses by Solar Radiation With Special Reference to COVID ‐19
AbstractUsing a model developed for estimating solar inactivation of viruses of biodefense concerns, we calculated the expected inactivation of SARS ‐CoV‐2 virus, cause of COVID‐19 pandemic, by artificial UVC and by solar ultraviolet radiation in several cities of the world during different times of the year. The UV sensitivity estimated here for SARS‐CoV‐2 is compared with those reported for other ssRNA viruses, including influenza A virus. The results indicate that SARS‐CoV‐2 aerosolized from infected patients and deposited on surfaces could remain infectious outdoors for considerable time during the winter...
Source: Photochemistry and Photobiology - June 5, 2020 Category: Science Authors: Jose ‐Luis Sagripanti, C. David Lytle Tags: RAPID COMMUNICATION Source Type: research

A Comparison of Solar Ultraviolet Radiation Exposure in Urban Canyons in Venice, Italy and Johannesburg, South Africa
AbstractUrban environments can have high ‐risk spaces that can provide excess personal sun exposure, such as urban or street canyons, and the spaces between buildings, amongst others. In these urban spaces sun exposure can be high or low depending on several factors. Polysulphone film (PSF) was used to assess possible daily solar ultravi olet radiation (UVR) exposure in urban canyons in Venice, Italy and, for the first time in Africa, in Johannesburg, South Africa. The photodegradation of PSF upon solar exposure was monitored at a wavelength of 330 nm by ultraviolet‐visible spectrophotometry and the resultant change wa...
Source: Photochemistry and Photobiology - June 4, 2020 Category: Science Authors: Caradee Y Wright, D Jean du Preez, Bice S Martincigh, Martin W. Allen, Danielle A Millar, Bianca Wernecke, Suzana Blesic Tags: RESEARCH NOTE Source Type: research

A Simple Ni ‐based Metal–organic Framework as Catalyst for Dye‐sensitized Photocatalytic H2 Evolution from Water Reduction
AbstractMetal ‐organic frameworks (MOF) are recently developed coordination porous materials, and their unique structures are very conducive to catalytic reactions. In this paper,p‐benzenedicarboxylic acid (PBA)‐Ni2+ MOF materials (denoted as PBA ‐Ni‐x, where x represents the initial ratio of PBA to Ni2+) were synthesized by a hydrothermal method and characterized by X ‐ray diffraction (XRD), Fourier transform infrared spectra (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and N2 gas adsorption. H2 gas was produced using the synthesized MOF as a photocatalyst and Eosin Y as a phot...
Source: Photochemistry and Photobiology - June 3, 2020 Category: Science Authors: Xing Liu, Xujiao Lv, Hua Lai, Gang Peng, Zhengji Yi, Junhua Li Tags: RESEARCH ARTICLE Source Type: research

Involvement of Photoprotective Compounds of a Phenolic Nature in the Response of Arabidopsis Thaliana Leaf Tissues to Low ‐Intensity Laser Radiation
ABSTRACTThe influence of low ‐intensity laser radiation (LILR) on the changes in the content of anthocyanins, kaempferol, quercetin and their glycosides in the leaves of 5‐week‐old plants ofArabidopsis thaliana L. was studied by means of methods of high ‐performance liquid chromatography and gas chromatography mass spectrometry (GC‐MS). It was found that in the leaves subjected to a stimulating He‐Ne laser radiation dose (3.6 J/cm2, continuous wave radiation, wavelength – 632.8 nm, exposure time – 5 min), the radiation induced an increase in the content of such compounds, the most significant one be...
Source: Photochemistry and Photobiology - May 31, 2020 Category: Science Authors: Lyubov Dudareva, Vladislav Tarasenko, Elena Rudikovskaya Tags: RESEARCH ARTICLE Source Type: research

Long ‐term Effects of 222‐nm ultraviolet radiation C Sterilizing Lamps on Mice Susceptible to Ultraviolet Radiation
222 ‐nm UVC have been reported to exert sterilizing ability comparable to that of 254‐nm UVC without producing cyclobutane pyrimidine dimers (CPDs), the major DNA lesions caused by UV. We investigated the long‐term effects of 222‐nm UVC on skin usingXpa‐knockout mice, a highly photocarcinogenic phenotype mice. CPDs formation was recognized only in uppermost layer of epidermis with 222‐nm UVC exposure. No tumors were observed inXpa‐knockout mice and wild‐type mice by repetitive irradiation with 222‐nm UVC. These data reveal that 222‐nm UVC lamps can be safely used for sterilizing human skin as far as the...
Source: Photochemistry and Photobiology - May 31, 2020 Category: Science Authors: Nozomi Yamano, Makoto Kunisada, Sachiko Kaidzu, Kazunobu Sugihara, Aiko Nishiaki ‐Sawada, Hiroyuki Ohashi, Ai Yoshioka, Tatsushi Igarashi, Akihiro Ohira, Masaki Tanito, Chikako Nishigori Tags: Research Article Source Type: research

Distinguishing Activities in the Photodynamic Arsenals of the Pigmented Ciliates Blepharisma sinuosum Sawaya, 1940 and Blepharisma japonicum Suzuki, 1954 (Ciliophora: Heterotrichea)
AbstractBlepharismins are photodynamic hypericin ‐like dianthrones produced as a variable pigment blend inBlepharisma ciliates and mostly studied in the Afro ‐AsiaticB. japonicum. The present work describes the bioactivy of pigments from the BrazilianB. sinuosum. Comparative analyses showed that the pigments from both species can trigger photo ‐induced modifications in phospholipids, but different redox properties and biological activities were assigned for each pigment blend. Stronger activities were detected forB. sinuosum pigments, with the lethal concentration LC50 10 × lower thanB. japonicum pigments in li...
Source: Photochemistry and Photobiology - May 30, 2020 Category: Science Authors: J éssica Cavaleiro, Nathally B. Oliveira, Talita A. Ribeiro, Lohaine F. Guimarães, Noemi M. Fernandes, Inacio D. da Silva‐Neto, Flávia Marszaukowski, Karen Wohnrath, Cleber B. Barreto, Michael Schweikert, Giulio Petroni, Claudio Ortenzi, Tags: RESEARCH ARTICLE Source Type: research

A Photoprotective Effect by Cation ‐π‐Interaction? Quenching of Singlet Oxygen by an Indole‐Cation‐π Model System
AbstractWe investigated the effect of the cation ‐π interaction on the susceptibility of a tryptophan model system towards interaction with singlet oxygen, i.e. Type II photooxidation. The model system consists of two indole units linked to a lariat crown ether to measure the total rate of removal of singlet oxygen by the indole units in the pr esence of sodium cations (i.e. indole units subject to a cation‐π interaction) and in the absence of this interaction. We found that the cation‐π interaction significantly decreases the total rate of removal of singlet oxygen (kT) for the model system, i.e. (kT = 2.4 ...
Source: Photochemistry and Photobiology - May 30, 2020 Category: Science Authors: Gary E. Arevalo, David A. Cagan, Charlotte G. Monsour, Arman C. Garcia, Alison McCurdy, Matthias Selke Tags: RESEARCH ARTICLE Source Type: research

Upconversion Nanoparticle ‐Assisted Photopolymerization
The upconversion nanoparticles (UCNPs) absorb two or more low ‐energy photons at near‐infrared wavelength to emit high‐energy photons at UV/vis wavelength to excite the initiator to generate free radicals, which induce monomers to polymerize to form various nano/micro structures or macro gels. AbstractNear ‐infrared (NIR) laser has deeper penetration and lower thermal effect compared with ultraviolet–visible (UV/vis) laser. NIR laser can stimulate upconversion nanoparticles (UCNPs) to emit UV/vis light efficiently. Therefore, the UCNPs become an important kind of materials to produce upconversion luminescenc...
Source: Photochemistry and Photobiology - May 19, 2020 Category: Science Authors: Ke Wang, Jhair Pe ña, Jinfeng Xing Tags: Invited Review Source Type: research

Enrique San Rom án (1945–2019)
Homage to Enrique San Roman (1945 –2019). AbstractAn homage to the Argentinian Photochemist Enrique San Rom án is presented. Enrique led the Photochemistry and Chemical Kinetics research group in the Department of Inorganic, Analytical and Physical Chemistry in the Faculty of Exact and Natural Sciences of the University of Buenos Aires from 1984 until his death in July 2019. He left a strong legacy in Ch emical Kinetics and Photochemistry in Argentina. He is remembered as a meticulous and very knowledgeable scientist and teacher, a loyal friend and a generous and integer human being. (Source: Photochemistry and Photobiology)
Source: Photochemistry and Photobiology - May 18, 2020 Category: Science Authors: Pedro F. Aramend ía, Silvia E. Braslavsky, María Gabriela Lagorio Tags: Research Note Source Type: research

Insulin ‐like Growth Factor‐1 Impacts p53 Target Gene Induction in UVB‐irradiated Keratinocytes and Human Skin
AbstractThe tumor suppressor protein p53 limits mutagenesis in response to ultraviolet ‐B (UVB) light exposure by activating the transcription of genes that mitigate the damaging effects of UVB radiation on DNA. Because most non‐melanoma skin cancers (NMSCs) occur in older individuals, it is important to understand the process of mutagenesis in the geriatric skin microenvironment. Based on previous studies demonstrating that geriatric skin expresses lower levels of the growth factor insulin‐like growth factor‐1 (IGF‐1) than young adult skin, a role for IGF‐1 in the regulation of p53 target genes was investigate...
Source: Photochemistry and Photobiology - May 16, 2020 Category: Science Authors: Abdulrahman M.M. Alkawar, Amber J. Castellanos, M. Alexandra Carpenter, Rebekah J. Hutcherson, Mariyyah A.O. Madkhali, R. Michael Johnson, Michael Bottomley, Michael G. Kemp Tags: RESEARCH ARTICLE Source Type: research

Luminescence Activity Decreases When v ‐Coelenterazine Replaces Coelenterazine in Calcium‐regulated Photoprotein – A Theoretical and Experimental Study
AbstractCalcium ‐regulated photoprotein is found in at least five phyla of organisms. The light emitted by those photoproteins can be tuned by mutating the photoprotein and/or by modifying the substrate coelenterazine (CTZ). Thirty years ago, Shimomura observed that the luminescence activity of aequorin was drama tically reduced when the substrate CTZ was replaced by its analogv‐CTZ. The latter is formed by adding a phenyl ring to the π‐conjugated moiety of CTZ. The decrease in luminescence activity has not been understood until now. In this paper, through combined quantum mechanics and molecular mechanics calcula...
Source: Photochemistry and Photobiology - May 16, 2020 Category: Science Authors: Bo ‐Wen Ding, Elena V. Eremeeva, Eugene S. Vysotski, Ya‐Jun Liu Tags: RESEARCH ARTICLE Source Type: research

Incorporation in Lipid Microparticles of Acid Red 87, a Colorant Used in Tattoo Inks: Effect on Photodegradation Under Simulated Sunlight and Laser Radiation
The incorporation of the ink tattoo colorant, Acid Red 87 (C.I. 45380) in lipid microparticles while inhibiting the decomposition of the colorant induced by sunlight and thus limiting its fading and release of hazardous photoproducts, would not interfere with its removal by laser treatment, since the laser ‐induced decomposition of C.I. 45380 was not affected by incorporation of the coloring agent into the lipid microparticles. AbstractTattoo colorants decompose under solar radiation and when exposed to laser light for their removal, leading to the accumulation in the dermis of toxic products. Aim of this study was to de...
Source: Photochemistry and Photobiology - May 7, 2020 Category: Science Authors: Santo Scalia, Annachiara Dozzo, Sofia Magli, Giuseppe Scarcella Tags: Research Article Source Type: research

Oxidative Stress and Genotoxicity in Melanoma Induction: Impact on Repair Rather Than Formation of DNA Damage?
AbstractKeratinocytes and melanocytes, two cutaneous cell types located within the epidermis, are the origin of most skin cancers, namely carcinomas and melanomas. These two types of tumors differ in many ways. First, carcinomas are almost 10 times more frequent than melanomas. In addition, the affected cellular pathways, the mutated genes and the metastatic properties of the tumors are not the same. This review addresses another specificity of melanomas: the role of photo ‐oxidative stress. UVA efficiently produces reactive oxygen species in melanocytes, which results in more frequent oxidatively generated DNA lesions t...
Source: Photochemistry and Photobiology - May 4, 2020 Category: Science Authors: Thierry Douki Tags: INVITED REVIEW Source Type: research

Generation of Singlet Molecular Oxygen by Lipid Hydroperoxides and Nitronium Ion †
O2 (1Δg) is generated when lipid hydroperoxides (OAOOH, LAOOH and ChOOH) react with NO2+ AbstractSinglet molecular oxygen is a reactive species involved in biological oxidative processes. The major cellular targets of singlet molecular oxygen are unsaturated fatty acids in the membrane, as well as nucleic acids and proteins. The aim of this study was to investigate whether lipids and commercial hydroperoxides generate singlet molecular oxygen, in presence of nitronium and activated nitronium ion. For this purpose, monomol light emitted in the near ‐infrared region (λ = 1270 nm) was used to mon...
Source: Photochemistry and Photobiology - May 4, 2020 Category: Science Authors: Fernanda M. Prado, Alexsandra C. Scalfo, Sayuri Miyamoto, Marisa H.G. Medeiros, Paolo Di Mascio Tags: Special Issue Research Article Source Type: research

New Synthesized Galloyl ‐RGD Inhibits Melanogenesis by Regulating the CREB and ERK Signaling Pathway in B16F10 Melanoma Cells
In this study, we investigated the anti‐melanogenic effect of galloyl‐RGD and the underlying mechanism for this effect. Galloyl‐RGD markedly inhibited melanin content and tyrosinase activity in a concentration‐dependent manner. We also found that galloyl‐RGD decreased the levels of melanogenesis‐related gene and protein. In addition, galloyl‐RGD reduces intracellular cyclic adenosine monophosp hate (cAMP) levels that leads to inhibition of cAMP‐responsive element binding protein (CREB) phosphorylation and activates extracellular signal‐regulated kinase (ERK) expression. These results indicate that CREB an...
Source: Photochemistry and Photobiology - April 29, 2020 Category: Science Authors: Seo Yeon Shin, Sang Ouk Sun, Jae Yeon Ko, Yun Seo OH, Seung ‐Sik Cho, Dae‐Hun Park, Kyung Mok Park Tags: RESEARCH ARTICLE Source Type: research

Monitoring of Solar Irradiance in the High Andes
ABSTRACTSolar radiation has been measured in the high Andes near Laguna Lejia (latitude 23 ° 26’ 23.30" S, longitude 67° 38’ 14.29" W) at an elevation of 4715 m between December 2016 and December 2017. Irradiances were monitored in four wavelength channels: PAR (400 – 700 nm), UV‐A (315 – 400 nm), UV‐B (295 – 315 nm) and short‐wavelength UV‐B (295 – 310 nm) with a ne w radiometer. In addition, ambient temperatures were recorded. Record values have been found for PAR (exceeding 600 W m‐2), UV ‐A (close to 95 W m‐2), UV ‐B (3.13 W m‐2) and short ‐wavel...
Source: Photochemistry and Photobiology - April 29, 2020 Category: Science Authors: Donat ‐Peter Häder, Nathalie A. Cabrol Tags: RESEARCH ARTICLE Source Type: research

Exploring Modes of Photokilling by Hypericin
ABSTRACTEffects of photodynamic therapy (PDT) using the anthraquinone hypericin were explored with OVCAR ‐5 cellsin vitro. Irradiation resulted in ER> lysosomal photodamage. Paraptosis was identified as a primary death pathway resulting from ER perturbation. This is characterized by an extensive pattern of cytoplasmic vacuole formation. As the PDT dose increased, apoptotic death was also detected. The cytoprotective effect of autophagy, observed when certain other sub ‐cellular sites are PDT targets, appears to be absent. These results, together with prior evidence that paraptosis can be lethal to cells with an impa...
Source: Photochemistry and Photobiology - April 28, 2020 Category: Science Authors: David Kessel Tags: RESEARCH ARTICLE Source Type: research

Singlet Oxygen Luminescence Image in Blood Vessels During Vascular ‐Targeted Photodynamic Therapy
In this study, the previously developed near ‐infrared (NIR) optical imaging system was optimized for fast imaging of1O2 luminescence. The optical imaging system enables direct imaging of1O2 luminescence in blood vessels within 2  s during vascular‐targeted PDT (V‐PDT), which makes this system extremely practical forin vivo studies. The dependence of RB concentration on1O2 luminescence image was investigated for V ‐PDT, and the data imply that 1270 nm signal is attributed to1O2 luminescence. The imaging system operates with a field of view of 9.60  × 7.68 mm2 and a spatial resolution ...
Source: Photochemistry and Photobiology - April 20, 2020 Category: Science Authors: Lisheng Lin, Huiyun Lin, Yi Shen, Defu Chen, Ying Gu, Brian C. Wilson, Buhong Li Tags: Special Issue Research Article Source Type: research

The Ca2+ ‐regulated Photoprotein Obelin as a Tool for SELEX Monitoring and DNA Aptamer Affinity Evaluation
ABSTRACTBioluminescent solid ‐phase analysis was proposed to monitor the selection process and to determine binding characteristics of the aptamer‐target complexes during design and development of the specific aptamers. The assay involves Ca2+‐regulated photoprotein obelin as a simple, sensitive and fast reporter. Applicability and the prospects of the approach were exemplified by identification of DNA aptamers to cardiac troponin I, a highly specific early biomarker for acute myocardial infarction. Two structurally different aptamers specific to various epitopes of troponin I were obtained and then tested in a model...
Source: Photochemistry and Photobiology - April 18, 2020 Category: Science Authors: Vasilisa V. Krasitskaya, Natalia S. Goncharova, Vladislav V. Biriukov, Eugenia E. Bashmakova, Marsel R. Kabilov, Ivan K. Baykov, Aleksey E. Sokolov, Ludmila A. Frank Tags: RESEARCH ARTICLE Source Type: research

Pretreatment of Root Canal with Photodynamic Therapy Facilitates Adhesion, Viability and Differentiation of Stem Cells of the Apical Papilla
This study was to test the hypothesis that root canal pretreated with photodynamic therapy (PDT) would promote stem cells from the apical papilla (SCAP) adhesion, proliferation and differentiation without affecting smear layer removal and microhardness of root canal. Standardized root canals were randomized into four groups (n = 30/group): (1) sodium hypochlorite(NaOCl) group, (2) NaOCl + ethylene diaminetetraacetic acid (EDTA) group, (3) NaOCl + PDT group, (4) NaOCl + EDTA + PDT group. After treatments, smear layer removal and microhardness of root canal were evaluated. SC...
Source: Photochemistry and Photobiology - April 16, 2020 Category: Science Authors: Yijun Li, Huan Ge, Lixuan Wu, Lishan Lei, Yanhuang Wang, Shan Jiang, Zhiyu Cai, Xiaojing Huang Tags: Research Article Source Type: research

Influence of Surface Structure, Pigmentation and Particulate Matter on Plant Reflectance and Fluorescence
ABSTRACTOptical properties of plant leaves are relevant to evaluate their physiological state and stress effect. The main objective of this work was to study how variegation, pigment composition or reflective features modify leaves photophysical behavior. For this purpose, green leaves (Ficus benjamina), purple leaves (Tradescantia pallida), green leaves covered by white trichomes (Cineraria maritima) and variegated leaves (Codiaeum aucubifolium) were analyzed. Firstly, foliar surface morphology was evaluated by scanning electron microscopy. UV ‐vis and near‐IR reflectance and transmittance spectra were obtained to cal...
Source: Photochemistry and Photobiology - April 15, 2020 Category: Science Authors: Nahuel I. Cuba, Rocio Torres, Enrique San Roman, M. Gabriela Lagorio Tags: SPECIAL ISSUE RESEARCH ARTICLE Source Type: research

Experimental and Theoretical Study of the Stability of the Complex Fisetin –Cu(II) and A Comparative Study of Free Ligand and Complex Interaction with Molecular Singlet Oxygen
Flavonoids can exert protection against oxidative damage caused by reactive oxygen species, and this biological activity could be affected by chelation with metallic ions. The stoichiometry and the apparent formation constant of the fisetin –Cu(II) complex were determined. The molecular structure of fisetin shows two possible chelation sites. A molecular modeling analysis of fisetin and its complex was performed to study spectroscopic properties and compared with experimental data. AbstractIn this work, the flavonol fisetin was selected in order to study its reactivity against Cu(II), a metal ion of interest in biolo...
Source: Photochemistry and Photobiology - April 11, 2020 Category: Science Authors: Vanesa A. Mu ñoz, Frida C. D. Dimarco Palencia, Matias I. Sancho, Sandra Miskoski, Norman A. García, Gabriela V. Ferrari, María Paulina Montaña Tags: Research Article Source Type: research

Recapitulation of Hypoxic Tumor –stroma Microenvironment to Study Photodynamic Therapy Implications
In this study, we demonstrated the consequences of a hypoxic stromal phenotype on tumor mass for exploring PDT response. We mimicked TME complexity implementing colon cancer cells and fibroblasts 3D cultures called spheroids. Using hypoxia reporting lines, we verified that homotypic spheroids exhibited a size ‐dependent transcriptional HIF‐1 activity. When cocultured, fibroblasts were localized in the hypoxic core. In homotypic stromal spheroids, the distribution of the endogenous photosensitizer PpIX was homogeneous while decreased in hypoxic areas of tumor 3D cultures. When monocultured, fibroblast s were more effici...
Source: Photochemistry and Photobiology - April 11, 2020 Category: Science Authors: Mar ía Julia Lamberti, Ana Belén Morales Vasconsuelo, María Gracia Ferrara, Natalia Belén Rumie Vittar Tags: Research Article Source Type: research

Issue Information
Photochemistry and Photobiology, Volume 96, Issue 2, Page 215-216, March/April 2020. (Source: Photochemistry and Photobiology)
Source: Photochemistry and Photobiology - April 6, 2020 Category: Science Tags: Issue Information Source Type: research

In Memoriam Jarod C. Finlay, PhD
Photochemistry and Photobiology, Volume 96, Issue 2, Page 218-218, March/April 2020. (Source: Photochemistry and Photobiology)
Source: Photochemistry and Photobiology - April 6, 2020 Category: Science Authors: Theresa M. Busch, Keith A. Cengel, Timothy C. Zhu Tags: Editorial Source Type: research

Editorial
Photochemistry and Photobiology, Volume 96, Issue 2, Page 217-217, March/April 2020. (Source: Photochemistry and Photobiology)
Source: Photochemistry and Photobiology - April 6, 2020 Category: Science Authors: Jean Cadet Tags: Editorial Source Type: research

Photochemical behavior of some estrone aryl and methyl sulfonates in solution: Preparative and mechanistic studies
AbstractDirect irradiation of estrone aryl and methyl sulfonates in different organic solvents under nitrogen atmosphere was investigated under steady ‐state conditions. The estrone derivatives reacted efficiently through the photo‐Fries rearrangement reaction involving [1;3]‐sulfonyl migration providing theortho‐sulfonyl estrone derivatives and estrone as the photoproducts. In addition, estrone and 2‐arylsulfonyl estrone derivatives were epimerized involving a Norrish Type I reaction. Chemical quenching and photosensitization experiments on the photoreaction have been also carried out to establish the photo reac...
Source: Photochemistry and Photobiology - April 4, 2020 Category: Science Authors: Mat ías I. Quindt, Gabriel F. Gola, Javier A. Ramirez, Sergio M. Bonesi Tags: SPECIAL ISSUE RESEARCH ARTICLE Source Type: research

Ratiometric fluorescent paper ‐based sensor based on CdTe quantum dots and graphite carbon nitride hybrid for visual and rapid determination of Cu2+ in drinks
AbstractA simple and effective ratiometric fluorescent sensor of CdTe QDs/GCNNs for on ‐site and rapid analysis of Cu2+ has been established by mixing physically CdTe QDs and graphite carbon nitride (GCNNs). Two emissions peaks of CdTe QDs at 572 nm and GCNNs at 436 nm are both excitated at 340 nm. Under a UV lamp, fluorescent of traffic yellow CdTe QDs is linearly quenched by Cu2+ (as the detection signal), while blue GCNNs remains unchanged (as the reference), resulting in a distinguishable color change gradually from pink yellow to blue. The limit of detection (LOD) of this new sensor for Cu2+ is as low as 0.47 ng mL...
Source: Photochemistry and Photobiology - April 3, 2020 Category: Science Authors: Kaili He, Xin Zhan, Lian Liu, Xiaohong Ruan, Yiwei Wu Tags: METHOD ARTICLE Source Type: research

Why are the elemental nonmetals (F2, Cl2, Br2, I2, S8, P4) of so many hues or of any hues and where is the chromophore? Insight into intera ‐X–X bonds
AbstractA unique approach is used to relate the HOMO ‐LUMO energy difference to the difference between the ionization potential (IP) and electron affinity (EA) to assist in deducing not only the colors, but also chromophores in elemental nonmetals. Our analysis focuses on compounds with lone pair electrons and σ electrons, namely X2 (X = F, Cl, Br, I), S8, and P4. For the dihalogens, the [IP – EA] energies are found to be: F2 (12.58 eV), Cl2 (8.98 eV), Br2 (7.90 eV), I2 (6.78 eV). We suggest that theinterahalogen X –X bond itself is the chromophore for these dihalogens, in which the light absorbed by th...
Source: Photochemistry and Photobiology - April 3, 2020 Category: Science Authors: Shakeela Jabeen, Alexander Greer, Kathleen F. Edwards, Joel F. Liebman Tags: RESEARCH NOTE Source Type: research

Psoralen Derivatives with Enhanced Potency
In this study, we re port a library of 73 novel psoralens, the largest collection of its kind. When screened for the ability to induce cell death, we identified two derivatives even more cytotoxic than 4’‐aminomethyl‐4,5’,8‐trimethylpsoralen (AMT), one of the most potent psoralens identified to date. Using MAL DI‐TOF MS, we studied the DNA adduct formation of a subset of novel psoralens and found that in most cases enhanced DNA binding correlated well with cytotoxicity. Generally, our most active derivatives contain positively charged substituents, which we believe increase DNA affinity and enhance psor...
Source: Photochemistry and Photobiology - March 30, 2020 Category: Science Authors: Alexandru D. Buhimschi, David M. Gooden, Hongwu Jing, Diane R. Fels, Katherine S. Hansen, Wayne F. Beyer, Mark W. Dewhirst, Harold Walder, Francis P. Gasparro Tags: RESEARCH ARTICLE Source Type: research

Targeted Photodynamic Therapy of Human Head and Neck Squamous Cell Carcinoma with Anti ‐epidermal Growth Factor Receptor Antibody Cetuximab and Photosensitizer IR700DX in the Mouse Skin‐fold Window Chamber Model
In this study the EGFR over‐expressing human head/neck OSC‐19‐luc2‐cGFP tumour with transfected GFP gen e was used in a skin‐fold window‐chamber model in BALB/c nude mice. The uptake and localization of the conjugate in the tumour and its surrounding normal tissues were studied by an intravital confocal laser scanning microscopy with image analyses. The tumour was also irradiated with 690 nm las er light 24 hours after conjugate administration. The vascular and tumour responses were examined by morphological evaluation and immunohistochemistry (IHC). The amount of conjugate in the tumour peaked at 24‐4...
Source: Photochemistry and Photobiology - March 30, 2020 Category: Science Authors: Wei Peng, Henriette S. de Bruijn, Timo L.M. ten Hagen, Go M. van Dam, Jan L.N. Roodenburg, Kristian Berg, Max J.H. Witjes, Dominic J. Robinson Tags: SPECIAL ISSUE RESEARCH ARTICLE Source Type: research

Differential responses of growth and photochemical performance of marine diatoms to ocean warming and high light irradiance
In this study we examined the consequences of such changes for the growth and photo‐physiology of two diatoms by mimicking the scenarios that correspond to present day and that predicted for the end of this century. Elevated light induced higher rates of damage to photosystem II (PSII) that significantly reduced photochemical yields of both diatoms. Treatments including UV radiation induced ~ 50% inhibition of PSII under present PAR levels. Generally, warming alleviated UVR inhibition, resulting in higher photochemical yields, and faster recovery during dim light exposure. Therefore, concurrent increase of irradiance and...
Source: Photochemistry and Photobiology - March 30, 2020 Category: Science Authors: Yaping Wu, Mengjuan Zhang, Zhenzhen Li, Juntian Xu, John Beardall Tags: RESEARCH ARTICLE Source Type: research

Long ‐term effects of 222 nm ultraviolet radiation C sterilizing lamps on mice susceptible to ultraviolet radiation
ABSTRACTGermicidal lamps that emit primarily 254 nm ultraviolet radiation (UV) are routinely utilized for surface sterilization but cannot be used for human skin because they cause genotoxicity. As an alternative, 222 nm ‐UVC have been reported to exert sterilizing ability comparable to that of 254 nm‐UVC without producing cyclobutane pyrimidine dimers (CPDs), the major DNA lesions caused by UV. However, there has been no clear evidence for safety in chronic exposure to skin, particularly with respect to carcino genesis. We therefore investigated the long‐term effects of 222 nm‐UVC on skin using a highly photocarci...
Source: Photochemistry and Photobiology - March 30, 2020 Category: Science Authors: Nozomi Yamano, Makoto Kunisada, Sachiko Kaidzu, Kazunobu Sugihara, Aiko Nishiaki ‐Sawada, Hiroyuki Ohashi, Ai Yoshioka, Tatsushi Igarashi, Akihiro Ohira, Masaki Tanito, Chikako Nishigori Tags: RESEARCH ARTICLE Source Type: research

Targeted Photodynamic Therapy of Human Head and Neck Squamous Cell Carcinoma with Anti ‐epidermal Growth Factor Receptor Antibody Cetuximab and Photosensitizer IR700DX in the Mouse Skin‐fold Window Chamber Model
In this study the EGFR over‐expressing human head/neck OSC‐19‐luc2‐cGFP tumour with transfected GFP gen e was used in a skin‐fold window‐chamber model in BALB/c nude mice. The uptake and localization of the conjugate in the tumour and its surrounding normal tissues were studied by an intravital confocal laser scanning microscopy with image analyses. The tumour was also irradiated with 690 nm las er light 24 hours after conjugate administration. The vascular and tumour responses were examined by morphological evaluation and immunohistochemistry (IHC). The amount of conjugate in the tumour peaked at 24‐4...
Source: Photochemistry and Photobiology - March 29, 2020 Category: Science Authors: Wei Peng, Henriette S. de Bruijn, Timo L.M. ten Hagen, Go M. van Dam, Jan L.N. Roodenburg, Kristian Berg, Max J.H. Witjes, Dominic J. Robinson Tags: SPECIAL ISSUE RESEARCH ARTICLE Source Type: research

Differential responses of growth and photochemical performance of marine diatoms to ocean warming and high light irradiance
In this study we examined the consequences of such changes for the growth and photo‐physiology of two diatoms by mimicking the scenarios that correspond to present day and that predicted for the end of this century. Elevated light induced higher rates of damage to photosystem II (PSII) that significantly reduced photochemical yields of both diatoms. Treatments including UV radiation induced ~ 50% inhibition of PSII under present PAR levels. Generally, warming alleviated UVR inhibition, resulting in higher photochemical yields, and faster recovery during dim light exposure. Therefore, concurrent increase of irradiance and...
Source: Photochemistry and Photobiology - March 29, 2020 Category: Science Authors: Yaping Wu, Mengjuan Zhang, Zhenzhen Li, Juntian Xu, John Beardall Tags: RESEARCH ARTICLE Source Type: research

Long ‐term effects of 222 nm ultraviolet radiation C sterilizing lamps on mice susceptible to ultraviolet radiation
ABSTRACTGermicidal lamps that emit primarily 254 nm ultraviolet radiation (UV) are routinely utilized for surface sterilization but cannot be used for human skin because they cause genotoxicity. As an alternative, 222 nm ‐UVC have been reported to exert sterilizing ability comparable to that of 254 nm‐UVC without producing cyclobutane pyrimidine dimers (CPDs), the major DNA lesions caused by UV. However, there has been no clear evidence for safety in chronic exposure to skin, particularly with respect to carcino genesis. We therefore investigated the long‐term effects of 222 nm‐UVC on skin using a highly photocarci...
Source: Photochemistry and Photobiology - March 29, 2020 Category: Science Authors: Nozomi Yamano, Makoto Kunisada, Sachiko Kaidzu, Kazunobu Sugihara, Aiko Nishiaki ‐Sawada, Hiroyuki Ohashi, Ai Yoshioka, Tatsushi Igarashi, Akihiro Ohira, Masaki Tanito, Chikako Nishigori Tags: RESEARCH ARTICLE Source Type: research