keyword
MENU ▼
Read by QxMD icon Read
search

Photoprotection

keyword
https://www.readbyqxmd.com/read/27932255/triolein-reduces-mmp-1-upregulation-in-dermal-fibroblasts-generated-by-ros-production-in-uvb-irradiated-keratinocytes
#1
Gustavo J Leirós, Ana Gabriela Kusinsky, María Eugenia Balañá, Karin Hagelin
BACKGROUND: Cytokine production and oxidative stress generated by ultraviolet radiation B (UVB) skin exposure are main factors of skin photoaging. Interleukin-6 (IL-6) produced by irradiated keratinocytes is proposed to have a role in metalloproteinases (MMPs) expression activation in dermal fibroblasts. OBJECTIVES: We examined the effect of triolein treatment of UVB-irradiated keratinocytes on MMP1 (interstitial collagenase) expression response of dermal fibroblasts...
November 27, 2016: Journal of Dermatological Science
https://www.readbyqxmd.com/read/27930292/uv-b-photoreceptor-mediated-protection-of-the-photosynthetic-machinery-in-chlamydomonas-reinhardtii
#2
Guillaume Allorent, Linnka Lefebvre-Legendre, Richard Chappuis, Marcel Kuntz, Thuy B Truong, Krishna K Niyogi, Roman Ulm, Michel Goldschmidt-Clermont
Life on earth is dependent on the photosynthetic conversion of light energy into chemical energy. However, absorption of excess sunlight can damage the photosynthetic machinery and limit photosynthetic activity, thereby affecting growth and productivity. Photosynthetic light harvesting can be down-regulated by nonphotochemical quenching (NPQ). A major component of NPQ is qE (energy-dependent nonphotochemical quenching), which allows dissipation of light energy as heat. Photodamage peaks in the UV-B part of the spectrum, but whether and how UV-B induces qE are unknown...
December 5, 2016: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/27928824/dissecting-the-photoprotective-mechanism-encoded-by-the-flv4-2-operon-a-distinct-contribution-of-sll0218-in-photosystem-ii-stabilization
#3
Luca Bersanini, Yagut Allahverdiyeva, Natalia Battchikova, Steffen Heinz, Maija Lespinasse, Essi Ruohisto, Henna Mustila, Jörg Nickelsen, Imre Vass, Eva-Mari Aro
In Synechocystis sp. PCC 6803, the flv4-2 operon encodes the flavodiiron proteins Flv2 and Flv4 together with a small protein, Sll0218, providing photoprotection for Photosystem II (PSII). Here, the distinct roles of Flv2/Flv4 and Sll0218 were addressed, using a number of flv4-2 operon mutants. In the Δsll0218 mutant, the presence of Flv2/Flv4 rescued PSII functionality as compared to Δsll0218-flv2, where neither Sll0218 nor the Flv2/Flv4 heterodimer are expressed. Nevertheless, both the Δsll0218 and Δsll0218-flv2 mutants demonstrated deficiency in accumulation of PSII proteins suggesting a role for Sll0218 in PSII stabilization, which was further supported by photoinhibition experiments...
December 7, 2016: Plant, Cell & Environment
https://www.readbyqxmd.com/read/27920683/squamous-cell-carcinoma-in-african-children-with-xeroderma-pigmentosum-three-case-reports
#4
Mamadou Kaloga, Pauline Dioussé, Boubacar Ahy Diatta, Mariama Bammo, Sarah Kourouma, Almamy Diabate, Ndiaga Gueye, Haby Dione, Moussa Diallo, Bernard Marcel Diop
INTRODUCTION: Xeroderma pigmentosum is a rare autosomal recessive genetic disease. This disease predisposes patients to early-onset skin cancers, particularly squamous cell carcinoma. Here, we report 3 pediatric cases, including 2 deaths. OBSERVATION: The subjects included 2 boys and 1 girl with skin type VI. All subjects were from consanguineous marriages, and the average age was 7.6 years. The patients all had ulcerative budding tumor lesions in the cephalic region, and the mean disease duration was 18 months...
September 2016: Case Reports in Dermatology
https://www.readbyqxmd.com/read/27919227/high-light-stress-triggers-distinct-proteomic-responses-in-the-marine-diatom-thalassiosira-pseudonana
#5
Hong-Po Dong, Yue-Lei Dong, Lei Cui, Srinivasan Balamurugan, Jian Gao, Song-Hui Lu, Tao Jiang
BACKGROUND: Diatoms are able to acclimate to frequent and large light fluctuations in the surface ocean waters. However, the molecular mechanisms underlying these acclimation responses of diaotms remain elusive. RESULTS: In this study, we investigated the mechanism of high light protection in marine diatom Thalassiosira pseudonana using comparative proteomics in combination with biochemical analyses. Cells treated under high light (800 μmol photons m(-2)s(-1)) for 10 h were subjected to proteomic analysis...
December 5, 2016: BMC Genomics
https://www.readbyqxmd.com/read/27912180/radicals-formed-from-proton-loss-of-carotenoid-radical-cations-a-special-form-of-carotenoid-neutral-radical-occurring-in-photoprotection
#6
A Ligia Focsan, Lowell D Kispert
In an organized assembly in Arabidopsis thaliana plant, proton loss from the radical cation of zeaxanthin (Zea(+)) was found to occur under intense illumination, a possible component in photoprotection. A stable neutral radical is formed because of the favorable proton loss at C4(4') position(s) of the terminal ends of Zea(+) that extends the unpaired spin density distribution (notation Zea(4) or Zea(4') by symmetry). Proton loss from the radical cation of β-carotene (β-car(+)) to available proton acceptors was also detected in a PSII sample upon irradiation...
November 19, 2016: Journal of Photochemistry and Photobiology. B, Biology
https://www.readbyqxmd.com/read/27909300/cyanobacterial-photoprotection-by-the-orange-carotenoid-protein
#7
REVIEW
Diana Kirilovsky, Cheryl A Kerfeld
In photosynthetic organisms, the production of dangerous oxygen species is stimulated under high irradiance. To cope with this stress, these organisms have evolved photoprotective mechanisms. One type of mechanism functions to decrease the energy arriving at the photochemical centres by increasing thermal dissipation at the level of antennae. In cyanobacteria, the trigger for this mechanism is the photoactivation of a soluble carotenoid protein, the orange carotenoid protein (OCP), which is a structurally and functionally modular protein...
December 2, 2016: Nature Plants
https://www.readbyqxmd.com/read/27901343/colonization-of-snow-by-microorganisms-as-revealed-using-miniature-raman-spectrometers-possibilities-for-detecting-carotenoids-of-psychrophiles-on-mars
#8
Jan Jehlička, Adam Culka, Linda Nedbalová
We tested the potential of a miniaturized Raman spectrometer for use in field detection of snow algae pigments. A miniature Raman spectrometer, equipped with an excitation laser at 532 nm, allowed for the detection of carotenoids in cells of Chloromonas nivalis and Chlamydomonas nivalis at different stages of their life cycle. Astaxanthin, the major photoprotective pigment, was detected in algal blooms originating in snows at two alpine European sites that differed in altitude (Krkonoše Mts., Czech Republic, 1502 m a...
November 30, 2016: Astrobiology
https://www.readbyqxmd.com/read/27895208/diurnal-solar-energy-conversion-and-photoprotection-in-rice-canopies
#9
Katherine Georgina Meacham, Xavier Sirault, W Paul Quick, Susanne von Caemmerer, Robert T Furbank
Genetic improvement of photosynthetic performance of cereal crops and increasing the efficiency with which solar radiation is converted into biomass has recently become a major focus for crop physiologists and breeders. The pulse amplitude modulated chlorophyll fluorescence technique (PAM) allows quantitative leaf level monitoring of the utilization of energy for photochemical light conversion and photo-protection in natural environments, potentially over the entire crop lifecycle. Here the diurnal relationship between electron transport rate (ETR) and irradiance was measured in five cultivars of Oryza sativa in canopy conditions with PAM fluorescence under natural solar radiation...
November 28, 2016: Plant Physiology
https://www.readbyqxmd.com/read/27892893/photoprotective-and-radioprotective-properties-of-nitroxides-and-their-application-in-magnetic-resonance-imaging
#10
Marcin Lewandowski, Krzysztof Gwoździński
Nitroxides are a group of stable organic radicals of low molecular weight having a nitroxyl group > N-.O, which has an unpaired electron. The presence of this group allows a nitroxide to participate in redox reactions. They serve as mimics of superoxide dismutase (SOD) and have stimulative properties towards haemoproteins with catalase-like activity. Nitroxides oxidize Fe (II) to Fe (III) preventing the Fenton and Haber-Weiss reactions. As the radicals have the ability to scavenge other free radicals. Nitroxides are not immunogenic, and mutagenic and do not show toxicity to the human cells...
October 14, 2016: Postȩpy Higieny i Medycyny Doświadczalnej
https://www.readbyqxmd.com/read/27881991/dissecting-long-term-adjustments-of-photoprotective-and-photo-oxidative-stress-acclimation-occurring-in-dynamic-light-environments
#11
Shizue Matsubara, Trang Schneider, Veronica G Maurino
Changes in light intensity directly affect the performance of the photosynthetic apparatus. Light energy absorbed in excess of cells' needs leads to production of reactive oxygen species and photo-oxidative damage. Excess light in both constant and dynamic environments induces photoprotective acclimation in plants. Distinct sets of signals and regulatory mechanisms are involved in acclimatory adjustment of photoprotection and photosynthesis under constant and dynamic (fluctuating) light conditions. We are still far away from drawing a comprehensive picture of acclimatory signal transduction pathways, particularly in dynamic environments...
2016: Frontiers in Plant Science
https://www.readbyqxmd.com/read/27881112/photoprotective-potential-in-some-medicinal-plants-used-to-treat-skin-diseases-in-sri-lanka
#12
Mayuri Tharanga Napagoda, Benthota Malavi Arachchige Shamila Malkanthi, Subasinghe Appuhamillage Kaumudi Abayawardana, Mohomed Mallique Qader, Lalith Jayasinghe
BACKGROUND: The constant exposure to solar ultraviolet radiation (UV) has a variety of harmful effects on human health. Although synthetic sunscreen products have been introduced as a preventive/therapeutic strategy, with the realization of their adverse side effects, the recent trend is to search for human friendly alternative formulations especially of plant origin. Therefore, the present study focuses on evaluation of photoprotective activity of aqueous extracts (1 mg/ml) of eleven medicinal plants in Sri Lanka that have been widely employed in traditional medicine as treatment options for various skin diseases and to improve the complexion...
November 24, 2016: BMC Complementary and Alternative Medicine
https://www.readbyqxmd.com/read/27877061/aloe-sterol-supplementation-improves-skin-elasticity-in-japanese-men-with-sunlight-exposed-skin-a-12-week-double-blind-randomized-controlled-trial
#13
Miyuki Tanaka, Yuki Yamamoto, Eriko Misawa, Kazumi Nabeshima, Marie Saito, Koji Yamauchi, Fumiaki Abe, Fukumi Furukawa
BACKGROUND/OBJECTIVE: Recently, it was confirmed that the daily oral intake of plant sterols of Aloe vera gel (Aloe sterol) significantly increases the skin barrier function, moisture, and elasticity in photoprotected skin. This study aimed to investigate whether Aloe sterol intake affected skin conditions following sunlight exposure in Japanese men. METHODS: We performed a 12-week, randomized, double-blind, placebo-controlled study to evaluate the effects of oral Aloe sterol supplementation on skin conditions in 48 apparently healthy men (age range: 30-59 years; average: 45 years)...
2016: Clinical, Cosmetic and Investigational Dermatology
https://www.readbyqxmd.com/read/27870065/photoacclimatory-and-photoprotective-responses-to-cold-versus-heat-stress-in-high-latitude-reef-corals
#14
Stefanie Pontasch, Paul L Fisher, Thomas Krueger, Sophie Dove, William Leggat, Ove Hoegh-Guldberg, Simon K Davy
Corals at the world's southernmost coral reef of Lord Howe Island (LHI) experience large temperature and light fluctuations and need to deal with periods of cold temperature (< 18 °C), but few studies have investigated how corals are able to cope with these conditions. Our study characterized the response of key photophysiological parameters, as well as photoacclimatory and photoprotective pigments (chlorophylls, xanthophylls and β-carotene), to short-term (5-day) cold stress (~ 15 °C; 7 °C below control) in three LHI coral species hosting distinct Symbiodinium ITS2 types, and compared the coral-symbiont response to that under elevated temperature (~ 29 °C; 7 °C above control)...
November 21, 2016: Journal of Phycology
https://www.readbyqxmd.com/read/27856901/improving-photosynthesis-and-crop-productivity-by-accelerating-recovery-from-photoprotection
#15
Johannes Kromdijk, Katarzyna Głowacka, Lauriebeth Leonelli, Stéphane T Gabilly, Masakazu Iwai, Krishna K Niyogi, Stephen P Long
Crop leaves in full sunlight dissipate damaging excess absorbed light energy as heat. When sunlit leaves are shaded by clouds or other leaves, this protective dissipation continues for many minutes and reduces photosynthesis. Calculations have shown that this could cost field crops up to 20% of their potential yield. Here, we describe the bioengineering of an accelerated response to natural shading events in Nicotiana (tobacco), resulting in increased leaf carbon dioxide uptake and plant dry matter productivity by about 15% in fluctuating light...
November 18, 2016: Science
https://www.readbyqxmd.com/read/27847530/aqueous-extract-of-clerodendranthus-spicatus-exerts-protective-effect-on-uv-induced-photoaged-mice-skin
#16
Lan Wang, Xie Zhang, Yong-Xian Li, Lie-Qiang Xu, Cai-Lan Li, Zhen-Biao Zhang, Jia-Li Liang, Zi-Ren Su, Hui-Fang Zeng, Yu-Cui Li
Clerodendranthus spicatus (Thunb.) C.Y.Wu (CS) is commonly used to treat kidney diseases in traditional Chinese medicine for its prominent anti-inflammatory effect and nourishing function to kidneys. In this study, aqueous extract of CS was assessed for its protective effect on UV-induced skin damage of mice. The chemical compositions of CS aqueous extract were determined by HPLC-ESI-MS/MS, in which 10 components were identified. During the experimental period, CS (0.9, 1.8, and 3.6 g/mL) was externally applied to shaved dorsal skins of mice prior to UV irradiation, daily for ten weeks...
2016: Evidence-based Complementary and Alternative Medicine: ECAM
https://www.readbyqxmd.com/read/27837096/downregulation-of-the-alternative-sigma-factor-sigj-confers-a-photoprotective-phenotype-to-anabaena-pcc-7120
#17
Amit Srivastava, Klaus Brilisauer, Ashutosh K Rai, Anand Ballal, Karl Forchhammer, Anil K Tripathi
Alternative sigma factors belonging to the Group 3 are thought to play an important role in the adaptation of cyanobacteria to environmental challenges by altering expression of genes needed for coping with such stresses. In this study, the role of an alternative sigma factor, SigJ, was analyzed in the filamentous nitrogen-fixing cyanobacterium, Anabaena sp. PCC 7120 by knocking down the expression of the sigJ gene (alr0277) employing an anti-sense RNA-mediated approach. In the absence of any stress, the knock-down (KD0277) or the wild-type strain both grew similarly...
November 10, 2016: Plant & Cell Physiology
https://www.readbyqxmd.com/read/27837088/membrane-proteomic-insights-into-the-physiology-and-taxonomy-of-an-oleaginous-green-microalga
#18
Adriana Garibay-Hernández, Bronwyn J Barkla, Rosario Vera-Estrella, Alfredo Martinez, Omar Pantoja
Ettlia oleoabundans is a non-sequenced oleaginous green microalga. Despite the significant biotechnological interest in producing value-added compounds from the acyl-lipids of this microalga, a basic understanding of the physiology and biochemistry of oleaginous microalgae is lacking, especially under nitrogen deprivation conditions known to trigger lipid accumulation. Using an RNA-Seq-based proteomics approach together with manual annotation, we are able to provide the first membrane proteome of an oleaginous microalga...
November 8, 2016: Plant Physiology
https://www.readbyqxmd.com/read/27835850/rice-mutants-deficient-in-%C3%AF-3-fatty-acid-desaturase-fad8-fail-to-acclimate-to-cold-temperatures
#19
Altanzaya Tovuu, Ismayil S Zulfugarov, Guangxi Wu, In Soon Kang, Choongrak Kim, Byoung Yong Moon, Gynheung An, Choon-Hwan Lee
To investigate the role of ω-3 fatty acid (FA) desaturase (FAD8) during cold acclimation in higher plants, we characterized three independent T-DNA insertional knock-out mutants of OsFAD8 from rice (Oryza sativa L.). At room temperature (28 °C), osfad8 plants exhibited significant alterations in fatty acid (FA) unsaturation for all four investigated plastidic lipid classes. During a 5-d acclimation period at 4 °C, further changes in FA unsaturation in both wild-type (WT) and mutant plants varied according to the type of lipid...
November 3, 2016: Plant Physiology and Biochemistry: PPB
https://www.readbyqxmd.com/read/27829365/comparative-genomics-provides-new-insights-into-the-diversity-physiology-and-sexuality-of-the-only-industrially-exploited-tremellomycete-phaffia-rhodozyma
#20
Nicolás Bellora, Martín Moliné, Márcia David-Palma, Marco A Coelho, Chris Todd Hittinger, José P Sampaio, Paula Gonçalves, Diego Libkind
BACKGROUND: The class Tremellomycete (Agaricomycotina) encompasses more than 380 fungi. Although there are a few edible Tremella spp., the only species with current biotechnological use is the astaxanthin-producing yeast Phaffia rhodozyma (Cystofilobasidiales). Besides astaxanthin, a carotenoid pigment with potent antioxidant activity and great value for aquaculture and pharmaceutical industries, P. rhodozyma possesses multiple exceptional traits of fundamental and applied interest. The aim of this study was to obtain, and analyze two new genome sequences of representative strains from the northern (CBS 7918(T), the type strain) and southern hemispheres (CRUB 1149) and compre them to a previously published genome sequence (strain CBS 6938)...
November 9, 2016: BMC Genomics
keyword
keyword
13408
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"