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https://www.readbyqxmd.com/read/29782823/changing-the-site-energy-of-per-614-in-the-peridinin-chlorophyll-a-protein-does-not-alter-its-capability-of-chlorophyll-triplet-quenching
#1
Alessandro Agostini, Jens Niklas, Tim Schulte, Marilena Di Valentin, Marco Bortolus, Eckhard Hofmann, Wolfgang Lubitz, Donatella Carbonera
The peridinin-chlorophyll-a protein (PCP) is a water-soluble light harvesting protein of the dinoflagellate Amphidinium carterae, employing peridinin (Per) as the main carotenoid to fulfil light harvesting and photo-protective functions. Per molecules bound to the protein experience specific molecular surroundings which lead to different electronic and spectral properties. In the refolded N89 L variant PCP (N89 L-RFPCP) a significant part of the intensity on the long wavelength side of the absorption spectrum is shifted to shorter wavelengths due to a significant change in the Per-614 site energy...
May 18, 2018: Biochimica et Biophysica Acta
https://www.readbyqxmd.com/read/29773581/dynamic-changes-between-two-lhcx-related-energy-quenching-sites-control-diatom-photoacclimation
#2
Lucilla Taddei, Volha Chukhutsina, Bernard Lepetit, Giulio R Stella, Roberto Bassi, Herbert van Amerongen, Jean-Pierre Bouly, Marianne Jaubert, Giovanni Finazzi, Angela Falciatore
Marine diatoms are prominent phytoplankton organisms, optimally performing photosynthesis in extremely variable environments. Diatoms possess a strong ability to dissipate excess absorbed energy as heat via non-photochemical quenching (NPQ). This process relies on changes in carotenoid pigment composition (xanthophyll cycle) and on specific members of the light-harvesting complex (LHC) family specialized in photoprotection (LHCX), which potentially act as NPQ effectors. However, the link between light stress, NPQ, and the existence of different LHCX isoforms is not understood in these organisms...
May 17, 2018: Plant Physiology
https://www.readbyqxmd.com/read/29768722/genoprotective-effect-of-phyllanthus-orbicularis-extract-against-uva-uvb-and-solar-radiation
#3
Marioly Vernhes Tamayo, André Passaglia Schuch, Teiti Yagura, Luis Baly Gil, Carlos Frederico Martins Menck, Angel Sánchez-Lamar
One approach to protect the human skin against harmful effects of solar ultraviolet (UV) radiation is to use natural products as photoprotectors. In this work, the extract from specie Phyllanthus orbicularis K was evaluated as a protective agent against the photodamage by UVB, UVA artificial lamps and environmental sunlight exposure. The plasmid DNA solutions were exposed to radiations using the DNA-dosimeter system in presence of plant extract. The DNA repair enzymes, E. coli Formamidopyrimidine-DNA glycosylase (Fpg) and T4 bacteriophage endonuclease V (T4-endo V), were employed to discriminate oxidized DNA damage and cyclobutane pyrimidine dimers (CPD) respectively...
May 16, 2018: Photochemistry and Photobiology
https://www.readbyqxmd.com/read/29758545/protection-against-uv-induced-oxidative-stress-and-dna-damage-by-amazon-moss-extracts
#4
A S Fernandes, J L Mazzei, H Evangelista, M R C Marques, E R A Ferraz, I Felzenszwalb
Amazon mosses, such as Holomitriopsis laevifolia and Leucobryum sp. are naturally exposed to high levels of solar ultraviolet (UV) radiation. Theoretically, under environmental stress conditions these mosses have developed protective chemical and metabolic strategies against UV damage, by way of biosynthesis of secondary metabolites, such as flavonoids. The present paper aimed to evaluate the free-radical scavenging activity, and the photoprotective, mutagenic and photomutagenic potencies of the methanolic (ME), aqueous (AE), hydroalcoholic (HE), ethanolic (EE) extracts of H...
April 27, 2018: Journal of Photochemistry and Photobiology. B, Biology
https://www.readbyqxmd.com/read/29751729/unravelling-the-photoprotection-properties-of-mycosporine-amino-acid-motifs
#5
Jack Matthew Woolley, Michael Staniforth, Michael D Horbury, Gareth W Richings, Martin Wills, Vasilios G Stavros
Photoprotection from harmful ultraviolet (UV) radiation exposure is a key problem in modern society. Mycosporine like amino acids found in fungi, cyanobacteria, macroalgae, phytoplankton and humans, are already presenting a promising form of natural photoprotection in sunscreen formulations. Using time-resolved transient electronic absorption spectroscopy and guided by complementary ab initio calculations, we help to unravel how the core structures of these molecules perform under UV irradiation. Through such detailed insight into the relaxation mechanisms of these ubiquitous molecules, we hope to inspire new thinking in developing next generation sun protecting molecules...
May 11, 2018: Journal of Physical Chemistry Letters
https://www.readbyqxmd.com/read/29742305/red-grape-vitis-vinifera-l-flavonoids-down-regulate-collagen-type-iii-expression-after-uv-a-in-primary-human-dermal-blood-endothelial-cells
#6
Serena Di Francesco, Monica Savio, Nora Bloise, Giovanni Borroni, Lucia Anna Stivala, Riccardo G Borroni
Red grape (Vitis vinifera L.) flavonoids including flavan-3-ols (e.g., catechin and epicatechin), flavonols (e.g., quercetin) and anthocyanins (e.g., malvidin) exert anti-inflammatory and antioxidant activities. In the skin they also have a photoprotective action, and their effects have been extensively investigated in keratinocytes, melanocytes and fibroblasts. Despite their known effects also on blood vasculature, little is known on their activities on human dermal blood endothelial cells (HDBECs), which are critically involved in skin homeostasis as well as in the pathogenesis of neoplastic and inflammatory skin diseases...
May 9, 2018: Experimental Dermatology
https://www.readbyqxmd.com/read/29734688/skin-protective-nutraceuticals-the-current-evidence-in-brief
#7
Oroma Nwanodi
Nutraceuticals are important for healthy skin maintenance. Probiotics, phenolics, and vitamins are just a few of the nutraceuticals meant to potentially prevent and assist medical management of dermatologic conditions. Among these, probiotics, vitamin E, and green tea catechins may offer the broadest array of skin protective mechanisms with probiotics having the greatest clinical range. Probiotics’ amelioration of atopic dermatitis and opportunistic infections of skin burns has been targeted in recent research efforts...
May 4, 2018: Healthcare (Basel, Switzerland)
https://www.readbyqxmd.com/read/29732888/nanoencapsulation-of-cyanidin-3-o-glucoside-enhances-protection-against-uvb-induced-epidermal-damage-through-regulation-of-p53-mediated-apoptosis-in-mice
#8
Zhaohan Liu, Yunfeng Hu, Xia Li, Zhouxiong Mei, Shi Wu, Yong He, Xinwei Jiang, Jianxia Sun, Jianbo Xiao, Liehua Deng, Weibin Bai
Excess ultraviolet (UV) radiation causes numerous forms of skin damage. The aim of the present study was to assess and compare the photoprotective effects of cyanidin-3-O-glucoside (C3G) alone and encapsulated in chitosan nanoparticles (Nano-C3G) in a UVB-induced acute photodamage mouse model. Nano-C3G was developed from chitosan and sodium tripolyphosphate (TPP) by ionic gelation. The particle size, zeta potential, entrapment efficiency, drug loading, and in vitro release in 6 days were determined. Kunming (KM) mice were treated with Nano-C3G (125, 250, 500 µM) or C3G (500 µM) after part of the dorsal skin area was dehaired, and then exposed to 2 J/cm2 of UVB...
May 7, 2018: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/29729015/photoprotective-effects-of-a-multifunctional-hair-care-formulation-containing-botanical-extracts-vitamins-and-uv-filters
#9
Marcella Gabarra Almeida Leite, Patricia M B G Maia Campos
The aim of this study was to develop and evaluate the efficacy of a multifunctional hair care formulation - Hair BB Cream - containing botanical extracts of Camellia sinensis, Vitis vinifera and Euterpe orleacea, vitamins, amino acids, UV filters and silicones for hair treatment and prevention of UV damages. The in vitro antioxidant activity of the botanical extracts was evaluated using the DPPH and chemiluminescence methods. A tensile test, combability, shine and image analysis were performed to evaluate the efficacy of the formulation...
May 4, 2018: Photochemistry and Photobiology
https://www.readbyqxmd.com/read/29726917/ascorbate-mediated-regulation-of-growth-photoprotection-and-photoinhibition-in-arabidopsis-thaliana
#10
William Plumb, Alexandra J Townsend, Brwa Rasool, Sarah Alomrani, Nurhayati Razak, Barbara Karpinska, Alexander V Ruban, Christine H Foyer
The requirements of growth and photosynthesis for ascorbate were assessed under low (LL; 250 μmol m-2 s-1) or high (HL; 1600 μmol m-2 s-1) irradiance in wild type Arabidopsis thaliana and two ascorbate synthesis mutants (vtc2-1 and vtc2-4) that have 30% wild type ascorbate levels. The low ascorbate mutants had the same numbers of leaves but lower rosette area and biomass than the wild type under LL. Wild type plants experiencing HL had higher leaf ascorbate, anthocyanin and xanthophyll pigments than under LL...
May 3, 2018: Journal of Experimental Botany
https://www.readbyqxmd.com/read/29721927/estimations-of-retinal-blue-light-irradiance-values-and-melatonin-suppression-indices-through-clear-and-yellow-tinted-intraocular-lenses
#11
Masaki Tanito, Ichiya Sano, Tsutomu Okuno, Yoshihisa Ishiba, Akihiro Ohira
Spectral transmittance values in the wavelength range of 300 to 800 nanometers were measured using a spectrophotometer for 18 intraocular lenses (IOLs) including clear (ZCB00) and yellow-tinted (ZCB00V, both from AMO Japan) IOLs with three different lens powers. Also measured were the blue-light irradiance (BLI) values, which might reflect retinal damage caused by sunlight, and the melatonin suppression indices (MSIs), which might reflect the nonvisual photoreception function, through these IOLs. The BLIs (in mWcm-2 ) calculated were 7...
2018: Advances in Experimental Medicine and Biology
https://www.readbyqxmd.com/read/29716849/enhanced-uv-protection-of-ketoconazole-using-hyptis-suaveolens-micro-emulsion
#12
Ruttiros Khonkarn, Ornanong S Kittipongpatana, Vilai Boasouna, Siriporn Okonogi
Ketoconazole is photolabile antifungal drug. Photochemical reactions may decrease its therapeutic effect or induce toxic compounds. The aim of this study was to prepare ketoconazole loaded microemulsion containing H. suaveolens oil with antifungal and antioxidant powers in order to obtain effective antifungal formulation. The release study, antifungal activity and photostability test, were then evaluated. The results showed that optimized Hyptis suaveolens microemulsion for ketoconazole loading was selected through construction of pseudo-ternary phase diagrams...
May 2018: Pakistan Journal of Pharmaceutical Sciences
https://www.readbyqxmd.com/read/29707792/maintenance-of-pre-existing-dna-methylation-states-through-recurring-excess-light-stress
#13
Diep R Ganguly, Peter A Crisp, Steven R Eichten, Barry J Pogson
The capacity for plant stress priming and memory, and the notion of this being underpinned by DNA methylation-mediated memory is an appealing hypothesis for which there is mixed evidence. We previously established a lack of drought-induced methylome variation in Arabidopsis thaliana (Arabidopsis); however, this was tied to only minor observations of physiological memory. There are numerous independent observations demonstrating that photoprotective mechanisms, induced by excess-light (EL) stress, can lead to robust programmable changes in newly developing leaf tissues...
April 29, 2018: Plant, Cell & Environment
https://www.readbyqxmd.com/read/29702749/melatonin-and-its-derivatives-counteract-the-ultraviolet-b-radiation-induced-damage-in-human-and-porcine-skin-ex-vivo
#14
Cezary Skobowiat, Anna A Brożyna, Zorica Janjetovic, Jeayeng Saowanee, Allen S W Oak, Tae-Kang Kim, Uraiwan Panich, Russel J Reiter, Andrzej T Slominski
Melatonin and its derivatives [N1 -acetyl-N2 -formyl-5-methoxykynurenine (AFMK) and N-acetyl serotonin (NAS)] have broad spectrum protective effects against photocarcinogenesis, including both direct and indirect antioxidative actions, regulation of apoptosis and DNA damage repair; these data were primarily derived from in vitro models. This study evaluates possible beneficial effects of melatonin and its active derivatives against UVB-induced harm to human and porcine skin ex vivo and to cultured HaCaT cells...
April 27, 2018: Journal of Pineal Research
https://www.readbyqxmd.com/read/29697102/differential-reorganisation-of-cutaneous-elastic-fibres-a-comparison-of-the-in-vivo-effects-of-broadband-ultraviolet-b-versus-solar-simulated-radiation
#15
Nisamanee Charoenchon, Lesley E Rhodes, Suzanne M Pilkington, Mark D Farrar, Rachel E B Watson
Long-term exposure of human skin to ultraviolet radiation (UVR) in sunlight negatively impacts its appearance and function with photoaged skin having a characteristic leathery, rough appearance, with deep wrinkles. These clinical features of photodamage are thought to result from UVR-induced remodelling of the dermal extracellular matrix, particularly the elastic fibre system. There are few in vivo human data on the impact of acute UVR exposure on this fibre system and particularly solar-simulated radiation (SSR)-mediated effects...
April 26, 2018: Photochemical & Photobiological Sciences
https://www.readbyqxmd.com/read/29691848/children-sustain-high-levels-of-skin-dna-photodamage-with-a-modest-increase-of-serum-25-oh-d-3-after-a-summer-holiday-in-northern-europe
#16
J Narbutt, P A Philipsen, A Lesiak, T Sandberg Liljendahl, D Segerbäck, J Heydenreich, D Chlebna-Sokol, P Olsen, G I Harrison, A Pearson, K Baczynska, M Rogowski-Tylman, H C Wulf, A R Young
BACKGROUND: Childhood solar ultraviolet radiation (UVR) exposure increases the risk of skin cancer in adulthood, which is associated with mutations caused by UVR-induced cyclobutane pyrimidine dimers (CPD). Solar UVR is also the main source of vitamin D, essential for healthy bone development in children. OBJECTIVES: The impact of a 12-day Baltic Sea (54o N) beach holiday on serum 25-dihydroxyvitamin D (25(OH)D3 ) and CPD was assessed in 32 healthy Polish children (skin types I-IV)...
April 24, 2018: British Journal of Dermatology
https://www.readbyqxmd.com/read/29690549/astaxanthin-in-skin-health-repair-and-disease-a-comprehensive-review
#17
REVIEW
Sergio Davinelli, Michael E Nielsen, Giovanni Scapagnini
Astaxanthin, a xanthophyll carotenoid, is a secondary metabolite naturally synthesized by a number of bacteria, microalgae, and yeasts. The commercial production of this pigment has traditionally been performed by chemical synthesis, but the microalga Haematococcus pluvialis appears to be the most promising source for its industrial biological production. Due to its collective diverse functions in skin biology, there is mounting evidence that astaxanthin possesses various health benefits and important nutraceutical applications in the field of dermatology...
April 22, 2018: Nutrients
https://www.readbyqxmd.com/read/29679619/a-global-perspective-on-carotenoids-metabolism-biotechnology-and-benefits-for-nutrition-and-health
#18
REVIEW
Manuel Rodriguez Concepcion, Javier Avalos, M Luisa Bonet, Albert Boronat, Lourdes Gomez-Gomez, Damaso Hornero-Mendez, M Carmen Limon, Antonio J Meléndez-Martínez, Begoña Olmedilla-Alonso, Andreu Palou, Joan Ribot, Maria J Rodrigo, Lorenzo Zacarias, Changfu Zhu
Carotenoids are lipophilic isoprenoid compounds synthesized by all photosynthetic organisms and some non-photosynthetic bacteria and fungi. With some notable exceptions, animals (including humans) do not produce carotenoids de novo but take them in their diets. In photosynthetic systems carotenoids are essential for photoprotection against excess light and contribute to light harvesting, but perhaps they are best known for their properties as natural pigments in the yellow to red range. Carotenoids can be associated to fatty acids, sugars, proteins, or other compounds that can change their physical and chemical properties and influence their biological roles...
April 18, 2018: Progress in Lipid Research
https://www.readbyqxmd.com/read/29678104/ph-dependent-regulation-of-the-relaxation-rate-of-the-radial-anion-of-the-secondary-quinone-electron-acceptor-qb-in-photosystem-ii-as-revealed-by-fourier-transform-infrared-spectroscopy
#19
Yosuke Nozawa, Takumi Noguchi
Photosystem II (PSII) is a protein complex that preforms water oxidation using light energy in photosynthesis. In PSII, electrons abstracted from water are eventually transferred to the secondary quinone electron acceptor, QB, and upon double reduction, QB is converted to quinol by binding two protons. Thus, excess electron transfer in PSII increases the pH of the stroma. In this study, to investigate the pH-dependent regulation of the electron flow in PSII, we have estimated the relaxation rate of the QB- radical anion in the pH region between 5 and 8 by direct monitoring of its population using light-induced Fourier transform infrared (FTIR) difference spectroscopy...
April 20, 2018: Biochemistry
https://www.readbyqxmd.com/read/29672054/correlated-molecular-structural-motions-for-photoprotection-after-deep-uv-irradiation
#20
Longteng Tang, Yanli Wang, Liangdong Zhu, Che Lee, Chong Fang
Exposure to ultraviolet (UV) light could cause photodamage to biomolecular systems and degrade optoelectronic devices. To mitigate such detrimental effects from the bottom up, we strategically select a photosensitive molecule pyranine and implement femtosecond electronic and Raman spectroscopies to elucidate its ultrafast photoprotection mechanisms in solution. Our results show that pyranine undergoes excited state proton transfer (ESPT) in water while this process is blocked in methanol regardless of excitation wavelengths (267, 400 nm)...
April 19, 2018: Journal of Physical Chemistry Letters
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