Singlet Oxygen's Potential Role as a Nonoxidative Facilitator of Disulfide S –S Bond Rotation
A density functional theory study provides evidence that singlet oxygen binds to 1,2-dimethyldisulfane to form a peroxy intermediate. Mechanistic detail is provided for the singlet oxygen reaction, where a reduced energy for rotation about the S–S bond is found prior to departure of molecular oxygen. Notably, this disulfide O2-capture and release reaction is reminiscent of alkenes and polyenes that form peroxy intermediates, thereby facilitating their cis-trans isomerizations. AbstractThe role of singlet oxygen potentially mediating increased conformational flexibility of a disulfide was investigated. Density function...
Source: Photochemistry and Photobiology - October 19, 2022 Category: Science Authors: Oliver Turque,
Ryan M. O'Connor,
Alexander Greer Tags: Special Issue Research Article Source Type: research
Senolytic Drug Quercetin Rescues Survival from Blue Light Toxicity in Drosophila Model
In this study, Drosophila melanogaster was used as a model organism to investigate the protective effect of the senolytic drug quercetin on blue light toxicity. As one of the first senolytic drugs discovered, quercetin not only has antioxidant properties, but also has been used to treat various neurological disorders. Our study shows that quercetin can effectively prolong the survival of flies under blue light irradiation, and it significantly increases the egg production of female flies under blue light. In addition, after flies intaking quercetin under blue light, both the spontaneous activity and nutrient metabolism sho...
Source: Photochemistry and Photobiology - October 19, 2022 Category: Science Authors: Dake Zhang,
Jianying Shan,
Boying Liang,
Lichao Zhong,
Hao Tang,
Yifan Xu,
Hui Jin,
Yinfei Chen,
Jie Shen Tags: Research Article Source Type: research
Electronic Characterization of Vis –NIR Absorbing Noninnocent Ruthenium Oxyquinolate–merocyanine Complexes and their Photoacoustic Emission in Aqueous Micellar Solution
A series of bis-heteroleptic ruthenium(II) polypyridyl dyes incorporating π-accepting 5-(vinyl-cyanine)-8-oxyquinolate ligands are reported. Trends in the HOMO–LUMO bandgap exhibit an excellent correlation with increasing electron-acceptor strength of the terminal cyanine moiety. Intense vis–NIR molar extinction coefficients combined with rapid nonradiative decay, im parted by mixing of the Ru(dπ) − OQN(π) frontier orbitals, makes these complexes highly suited to photoacoustic applications. AbstractThe electronic and photophysical properties for a series of ruthenium(II) polypyridyl dyes are presented where a ...
Source: Photochemistry and Photobiology - October 18, 2022 Category: Science Authors: Peter Catsoulis,
Shengwei Wang,
Chandra Yelleswarapu,
Jonathan Rochford Tags: Special Issue Research Article Source Type: research
Comparison of Phosphorescent Pt(II) Complexes with C^N^N vs N^N^N Chelators and Caffeine ‐Based NHC‐co‐ligands
We explored coordination compounds featuring caffeine-based carbene-co-ligands and tridentate dianionic pincer luminophores for phosphorescent Pt(II) complexes. The influence of the different substituents at the chelating luminophores and of the caffeine-based NHC-co-ligand on the photophysical properties was assessed. ABSTRACTIn this work, we explored coordination compounds featuring caffeine-based carbene co-ligands and tridentate dianionic pincer luminophores derived from 2,6-bis(1H-1,2,4-triazol-5-yl)pyridine (N), as well as from 2-phenyl-6-(1H-1,2,4-triazol-5-yl)pyridine (C), bearing either Ad (adamantyl) ortBu (terti...
Source: Photochemistry and Photobiology - October 12, 2022 Category: Science Authors: Thomas M. Kirse,
Joschua L üke,
Iván Maisuls,
Alexander Hepp,
Cristian A. Strassert Tags: Special Issue Research Article Source Type: research
Treating Cancer with Herbs and Spices: The Legend of Curcumin
Where to find curcumin. (Source: Photochemistry and Photobiology)
Source: Photochemistry and Photobiology - October 11, 2022 Category: Science Authors: David Kessel Tags: Correspondence Source Type: research
Adjacent and Nonadjacent Dipyrimidine Photoproducts as Intrinsic Probes of DNA Secondary and Tertiary Structure
While irradiation of duplex DNA produces adjacentcis,syn cyclobutane pyrimidine dimers (CPDs), irradiation of other structures can produce other isomers, such as the nonadjacenttrans,anti CPD formed in G-quadruplexes. This review investigates the various types of adjacent and nonadjacent dipyrimidine photoproducts and methods for their detection that could be used to identify the presence of various types of unusual structures in DNA. AbstractWhile the photochemistry of duplex DNA has been extensively studied, the photochemistry of nonduplex DNA structures is largely unexplored. Because the structure and stereochemistry of...
Source: Photochemistry and Photobiology - October 7, 2022 Category: Science Authors: John ‐Stephen Taylor Tags: Special Issue Invited Review Source Type: research
Therapeutic Implications of UVB Irradiation in Cancer by Enhancing Anti ‐Tumor Immunity†
This study further provides the direction of new future research to explore moderate UVB irradiation in combination with checkpoint blockade antibodies to enhance immunotherapeutic response against various solid tumors. (Source: Photochemistry and Photobiology)
Source: Photochemistry and Photobiology - October 7, 2022 Category: Science Authors: Bilal Bin Hafeez,
Ed W. Alvarado,
Dae Joon Kim Tags: Highlight Article (Invited) Source Type: research
UV Radiation Exposure of Outdoor Workers in Antarctica
AbstractThe Antarctic region is a place of increasing interest. A growing number of personnel are working outdoors in extreme environmental conditions. They receive significant exposure to solar Ultraviolet radiation and are thereby at increased risk of adverse consequences. The aim of this study was to evaluate the UVR dose received by the outdoor workers at the Bulgarian Antarctic Base. Ten Caucasian healthy subjects, 8 male and 2 female with a mean age of 38 years (29-51) were enrolled. Of them 5 were scientists and 5 were logistic workers. We measured the accumulated daily dose of UVR assessed by Standard Erythemal ...
Source: Photochemistry and Photobiology - October 6, 2022 Category: Science Authors: Ivan Bogdanov,
Dimitar Cherkezov,
Stefan Velev,
Razvigor Darlenski Tags: Research Note Source Type: research
In Vitro Effect of 445 nm Blue Laser and 660 nm Low‐Level Laser on the Quantity and Quality of Human Gingival Fibroblasts
This study aimed to investigate the effect of 445 nm blue laser and 660 nm low-power laser on the quantity and quality of human gingival fibroblastsin vitro. In thisin vitro experimental study, 445 nm and 660 nm lasers were irradiated on the samples six times. After examining the cells on the 7th and 14th days, the data were analyzed using ANOVA PASS11 and thepost hoc Tukey test. The results showed the positive effect of the 660 nm laser on fibroblast proliferation. The viability on the 7th day was the highest in the control group, lowest in the 445 nm laser group and highest in the 660 nm laser gro...
Source: Photochemistry and Photobiology - October 5, 2022 Category: Science Authors: Kimia Hafezi Motlagh,
Arash Azizi,
Nahid Moezzi Ghadim Tags: Method Article Source Type: research
Squaraine Dyes as Fluorescent Turn ‐on Probes for Mucins: A Step Toward Selectivity†
The fluorescence intensity of a brominated indolenine squaraine can be turned-on by mucin glycoproteins by breaking down squaraines aggregates. AbstractMucins are a family of long polymeric glycoproteins which can be overexpressed in several types of cancers, and over recent years, great attention was addressed to identify mucins as an important biomarker of adverse prognosis. Fluorometric detection mediated by fluorescent probes could represent a winning strategy in the early diagnosis of different pathologies. Among promising biological fluorescent probes, squaraines are gaining particular attention, thanks to their shar...
Source: Photochemistry and Photobiology - October 5, 2022 Category: Science Authors: Cosmin Butnarasu,
Carlotta Pontremoli,
Maria Jesus Moran Plata,
Nadia Barbero,
Sonja Visentin Tags: Special Issue Research Article Source Type: research
Photoswitchable Phosphonate –Fullerene Hybrids with Cholinesterase Activity
Phosphonate –fullerene hybrids with three simultaneous characteristics—bioactivity, photoinduce change of bioactivity, selectivity of inhibition change to laser wavelength. AbstractModern progress in photopharmocology calls for new generation of compounds joining bioactivity, photoswitchable properties and high selectivity of response to light wavelength. Introduced here, phosphonate –fullerene hybrids are the first representatives of such compounds. Phosphonate–fullerene hybrids were synthesized on a base of fullerene C60 and organophosphates with the function of photoswitchable cholinesterase activity —phosphor...
Source: Photochemistry and Photobiology - October 2, 2022 Category: Science Authors: Ilya Kolesnikov,
Daria Mamonova,
Dmitrii Pankin,
Gulia Bikbaeva,
Anastasia Khokhlova,
Anna Pilip,
Anastasia Egorova,
Vladislav Zigel,
Alina Manshina Tags: Research Article Source Type: research
Ultrafast Radical Photogeneration Pathways in Eumelanin
AbstractEumelanin is a ubiquitous biological pigment that rapidly and efficiently deactivates excited states created by UV or visible radiation. Paradoxically, photoirradiation of eumelanin also generates radicals and harmful reactive oxygen species, but the relationship between these pathways and excited state deactivation is uncertain. Here, greatly expanding the excitation tuning range (225 –620 nm) and probing window (400–1500 nm) in femtosecond transient absorption spectroscopy of the synthetic eumelanin, DOPA melanin, enables the detection of photogenerated radials with ultrafast time resolution for the first tim...
Source: Photochemistry and Photobiology - September 30, 2022 Category: Science Authors: Christopher Grieco,
Forrest R. Kohl,
Bern Kohler Tags: Special Issue Research Article Source Type: research
Hydroalcoholic Extract of Encholirium spectabile Mart. (Bromeliaceae) in O/W Emulsions as an Additive against the UVB Radiation
AbstractThe use of sunscreen is one of the photoprotection measures most used by the population, so these products must offer broad spectrum protection against UVA and UVB radiation.Encholirium spectabile, popularly known as “macambira-de-flecha”, is a species characterized by its rocky outcrops and found in the Caatinga. This biome is known for extreme droughts and dry periods, and for this reason its vegetation needed to develop resistance mechanisms. The aim of this work was to evaluate the use ofE. spectabile incorporated in O/W emulsion as a potential photoprotective agent and their antioxidant activity. Four chem...
Source: Photochemistry and Photobiology - September 30, 2022 Category: Science Authors: Anne Caroline dos Santos Dantas,
Michele Mirian Calixto de Lira,
L ívia Macedo Dutra,
Cristiane Maria Souza de Castro Rodrigues,
Sílvio Alan Gonçalves Bonfim Reis,
Rosane Nora Castro,
Jackson Roberto Guedes da Silva Almeida Tags: Research Article Source Type: research
Comparison of Pulsed and Continuous Wave Diode Laser at 940 nm on the Viability and Migration of Gingival Fibroblasts
This study examined the effects of the emission mode of a 940 nm diode laser on the viability and migration of human gingival fibroblasts. Cells were cultured in a routine growth media and treated with PBM (average power 0.1 W cm−2, average fluence 3 J cm−2, every 12 h for six sessions) in one continuous wave and two pulsing settings with 20% and 50% duty cycles. Cell viability was assessed using MTT, and digital imaging quantified cell migration. After 48 and 72 h, all treatment groups had significantly higher viability (n = 6,P < 0.05) compared with the control. The highest viability was ...
Source: Photochemistry and Photobiology - September 29, 2022 Category: Science Authors: Marzieh Jazaeri,
Parviz Torkzaban,
Saeid Afshar,
Roya Najafi ‐Vosough,
Praveen Arany,
Leila Gholami Tags: Research Article Source Type: research
The Photosensitizer Temoporfin (mTHPC) – Chemical, Pre‐clinical and Clinical Developments in the Last Decade
AbstractThis review follows the research, development and clinical applications of the photosensitizer 5,10,15,20-tetra(m-hydroxyphenyl)chlorin (mTHPC, temoporfin) in photodynamic (cancer) therapy (PDT) and other medical applications. Temoporfin is the active substance in the medicinal product Foscan ® authorized in the EU for the palliative treatment of head and neck cancer. Chemistry, biochemistry and pharmacology, as well as clinical and other applications of temoporfin are addressed, including the extensive work that has been done on formulation development including liposomal formulations. The literature has been cov...
Source: Photochemistry and Photobiology - September 26, 2022 Category: Science Authors: Arno Wiehe,
Mathias O. Senge Tags: Special Issue Invited Review Source Type: research
