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https://www.readbyqxmd.com/read/28806684/photochemical-inactivation-of-lymphocytes-by-riboflavin-with-visible-light-for-ta-gvhd-prevention
#1
Qin Mo, Yuwen Huang, Li Wang, Zhenzhen Cheng, Xiaofei Wu, Yao Jia, Xun Wang, Bo Zhang
Transfusion-associated graft-versus-host disease (TA-GVHD) is a life-threatening complication caused by the input of a number of immunocompetent allogeneic lymphocytes. This study focus on the photochemical effects of riboflavin excited by visible light (RB+L) treatment on human lymphocytes, to study the feasibility of using RB+L treatment to prevent adverse immune reactions caused by transfused lymphocytes. 100μM riboflavin was added to lymphocyte suspensions. After exposure to 400-580nm visible light with a total energy of 40J/mL, cells were cultured and the ability of proliferation and cytokine secretion were assayed upon stimuli...
August 7, 2017: Journal of Photochemistry and Photobiology. B, Biology
https://www.readbyqxmd.com/read/28806683/asymmetric-polyplex-nanocapsules-loaded-with-photosentisizer-for-light-assisted-gene-transfer
#2
Xuemin Lu, Li Liu
Inefficient intracellular gene delivery is still a limitation for the clinical translation of gene therapy. Recently, photochemical internalization (PCI) has emerged with the opportunity to overcome endo-lysosomal sequestration in gene delivery, which utilizes photosensitizer (PS) plus light generating reactive oxygen species (ROS) at sub-lethal level to facilitate intracellularly targeted drug delivery. In this work, asymmetric polyplex-nanocapsules were prepared based on the triblock copolymers of PEG-PCL-PEI by using the simple solvent-injection method...
August 7, 2017: Journal of Photochemistry and Photobiology. B, Biology
https://www.readbyqxmd.com/read/28806547/environmental-life-cycle-assessment-of-seafood-production-a-case-study-of-trawler-catches-in-tunisia
#3
Khaled Abdou, Didier Gascuel, Joël Aubin, Mohamed Salah Romdhane, Frida Ben Rais Lasram, François Le Loc'h
The Gulf of Gabes is one of the most productive fishery areas in the southern Mediterranean Sea. It is archetypal of an ecosystem in which the effects of fisheries are most pronounced. Demersal trawling is the main fishing activity in the Gulf of Gabes. Life Cycle Assessment (LCA) was applied to assess the environmental performance landing 1t of seafood with wooden demersal trawlers in the Gulf of Gabes. Impact categories included in the study were abiotic depletion potential (ADP), acidification potential (AP), eutrophication potential (EP), global warming potential (GWP), ozone depletion potential (ODP), photochemical oxidant formation potential (POFP), human toxicity potential (HTP), marine eco-toxicity potential (METP), terrestrial eco-toxicity potential (TETP), land occupation potential (LOP), and total cumulative energy demand (TCED)...
August 11, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28806084/photochemical-activation-of-tertiary-amines-for-applications-in-studying-cell-physiology
#4
Naeem Asad, Davide Deodato, Xin Lan, Magnus B Widegren, David Lee Phillips, Lili Du, Timothy M Dore
Representative tertiary amines were linked to the 8-cyano-7-hydroxyquinolinyl (CyHQ) photoremovable protecting group (PPG) to create photoactivatable forms suitable for use in studying cell physiology. The photoactivation of tamoxifen and 4-hydroxytamoxifen, which can be used to activate Cre recombinase and CRISPR-Cas9 gene editing, demonstrated that highly efficient release of bioactive molecules could be achieved through 1- and 2-photon excitation (1PE and 2PE). CyHQ-protected anilines underwent a photo-aza-Claisen rearrangement instead of releasing amines...
August 14, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28806070/high-levels-of-daytime-molecular-chlorine-and-nitryl-chloride-at-a-rural-site-on-the-north-china-plain
#5
Xiaoxi Liu, Hang Qu, Lewis Gregory Huey, Yuhang Wang, Steven Sjostedt, Limin Zeng, Keding Lu, Yusheng Wu, Min Hu, Min Shao, Tong Zhu, Yuanhang Zhang
Molecular chlorine (Cl2) and nitryl chloride (ClNO2) concentrations were measured using chemical ionization mass spectrometry at a rural site over the North China Plain during June 2014. High levels of daytime Cl2 up to ~450 pptv were observed. The average diurnal Cl2 mixing ratios showed a maximum around noon at ~100 pptv. ClNO2 exhibited a strong diurnal variation with early morning maxima reaching ppbv levels and afternoon minima sustained above 60 pptv. A moderate correlation (R(2)=0.31) between Cl2 and sulfur dioxide was observed, perhaps indicating a role for power plant emissions in the generation of the observed chlorine...
August 14, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28805371/wavelength-resolved-photon-fluxes-of-indoor-light-sources-implications-for-hox-production
#6
Shawn Finley Kowal, Seth Robert Allen, Tara F Kahan
Photochemistry is a largely-unconsidered potential source of reactive species such as hydroxyl and peroxy radicals (OH and HO2, "HOx") indoors. We present measured wavelength-resolved photon fluxes and distance dependences of indoor light sources including halogen, incandescent, and compact fluorescent lights (CFL) commonly used in residential buildings; fluorescent tubes common in industrial and commercial settings; and sunlight entering buildings through windows. We use these measurements to predict indoor HOx production rates from the photolysis of nitrous acid (HONO), hydrogen peroxide (H2O2), ozone (O3), formaldehyde (HCHO) and acetaldehyde (CH3CHO)...
August 14, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28804804/life-cycle-environmental-impacts-of-bioethanol-production-from-sugarcane-molasses-in-iran
#7
Saeid Shahvarooghi Farahani, Mohammad Amin Asoodar
In recent years, bioethanol from sugarcane molasses has been produced on an industrial scale in Iran. The aim of this study was to evaluate molasses-based bioethanol production from an environmental point of view. Data were collected from Debel Khazai agro-industry situated in southern region of Iran by using face-to-face interviews and annual statistics of 2010 to 2016 (6-year life cycle of sugarcane cultivation). Ten impact categories including abiotic depletion (AD), acidification (AC), eutrophication (EP), global warming potential (GWP), ozone layer depletion (OLD), human toxicity (HT), freshwater aquatic ecotoxicity (FE), marine aquatic ecotoxicity (ME), terrestrial ecotoxicity (TE), and photochemical oxidation (PO) were selected based on CML methodology...
August 13, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28801049/a-four-state-parametric-model-for-the-kinetics-of-the-non-photochemical-quenching-in-photosystem-ii
#8
Joris J Snellenburg, Matthew P Johnson, Alexander V Ruban, Rienk van Grondelle, Ivo H M van Stokkum
The phenomenon of non-photochemical quenching (NPQ) was studied in spinach chloroplasts using pulse amplitude modulated (PAM) fluorometry. We present a new analysis method which describes the observed fluorescence quantum yield as the sum of the product of four different states of PsiI and their corresponding quantum yields. These four distinct states are PsiI in the quenched or unquenched state, and with its reaction center either open or closed depending upon the reduction of the QA site. With this method we can describe the dynamics of the NPQ induction and recovery as well as quantify the percentage of photoinactivated RC throughout the measurement...
August 8, 2017: Biochimica et Biophysica Acta
https://www.readbyqxmd.com/read/28800521/potassium-deficiency-alters-growth-photosynthetic-performance-secondary-metabolites-content-and-related-antioxidant-capacity-in-sulla-carnosa-grown-under-moderate-salinity
#9
Chokri Hafsi, Hanen Falleh, Mariem Saada, Riadh Ksouri, Chedly Abdelly
Salinity and K(+) deficiency are two environmental constraints that generally occur simultaneously under field conditions, resulting in severe limitation of plant growth and productivity. The present study aimed at investigating the effects of salinity, either separately applied or in combination with K(+) deficiency, on growth, photosynthetic performance, secondary metabolites content, and related antioxidant capacity in Sulla carnosa. Seedlings were grown hydroponically under sufficient (6000 μM) or low (60 μM) K(+) supply with 100 mM NaCl (C + S and D + S treatments, respectively)...
August 4, 2017: Plant Physiology and Biochemistry: PPB
https://www.readbyqxmd.com/read/28799757/immobilization-of-growth-factors-to-collagen-surfaces-using-visible-light
#10
Gabriella Maria Fernandes Cunha, Hyun Jong Lee, Alisha Kumar, Alexander Kreymerman, Sarah Christine Heilshorn, David Myung
In the treatment of traumatic injuries, burns, and ulcers of the eye, inadequate epithelial tissue healing remains a major challenge. Wound healing is a complex process involving the temporal and spatial interplay between cells and their extracellular milieu. It can be impaired by a variety of causes including infection, poor circulation, loss of critical cells and/or proteins, and a deficiency in normal neural signaling (e.g. neurotrophic ulcers). Ocular anatomy is particularly vulnerable to lasting morbidity from delayed healing, whether it be scarring or perforation of the cornea, destruction of the conjunctival mucous membrane, or cicatricial changes to the eyelids and surrounding skin...
August 11, 2017: Biomacromolecules
https://www.readbyqxmd.com/read/28799393/condensed-phase-electron-transfer-beyond-the-condon-approximation
#11
Michael G Mavros, Diptarka Hait, Troy Van Voorhis
Condensed phase electron transfer problems are often simplified by making the Condon approximation: the approximation that the coupling connecting two charge-transfer diabatic states is a constant. Unfortunately, the Condon approximation does not predict the existence of conical intersections, which are ubiquitous in both gas-phase and condensed-phase photochemical dynamics. In this paper, we develop a formalism to treat condensed-phase dynamics beyond the Condon approximation. We show that even for an extremely simple test system, hexaaquairon(ii)/hexaaquairon(iii) self-exchange in water, the electronic coupling is expected to fluctuate rapidly and non-Condon effects must be considered to obtain quantitatively accurate ultrafast nonequilibrium dynamics...
December 7, 2016: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28799338/negative-ion-photoelectron-spectra-of-iso3-is2o3-and-is2o4-intermediates-formed-in-interfacial-reactions-of-ozone-and-iodide-sulfite-aqueous-microdroplets
#12
Zhengbo Qin, Gao-Lei Hou, Zheng Yang, Marat Valiev, Xue-Bin Wang
Three short-lived, anionic intermediates, ISO3(-), IS2O3(-), and IS2O4(-), are detected during reactions between ozone and aqueous iodine/sulfur oxide microdroplets. These species may play an important role in ozone-driven inorganic aerosol formation; however their chemical properties remain largely unknown. This is the issue addressed in this work using negative ion photoelectron spectroscopy (NIPES) and ab initio modeling. The NIPE spectra reveal that all of the three anionic species are characterized by high adiabatic detachment energies (ADEs) - 4...
December 7, 2016: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28799332/attaching-the-nora-efflux-pump-inhibitor-inf55-to-methylene-blue-enhances-antimicrobial-photodynamic-inactivation-of-methicillin-resistant-staphylococcus-aureus-in-vitro-and-in-vivo
#13
Ardeshir Rineh, Naveen K Dolla, Anthony R Ball, Maria Magana, John B Bremner, Michael R Hamblin, George P Tegos, Michael J Kelso
Antimicrobial photodynamic inactivation (aPDI) uses photosensitizers (PSs) and harmless visible light to generate reactive oxygen species (ROS) and kill microbes. Multidrug efflux systems can moderate the phototoxic effects of PSs by expelling the compounds from cells. We hypothesized that increasing intracellular concentrations of PSs by inhibiting efflux with a covalently attached efflux pump inhibitor (EPI) would enhance bacterial cell phototoxicity and reduce exposure of neighbouring host cells to damaging ROS...
August 11, 2017: ACS Infectious Diseases
https://www.readbyqxmd.com/read/28796442/total-environmental-impacts-of-biofuels-from-corn-stover-using-a-hybrid-life-cycle-assessment-lca-model-combining-process-lca-and-economic-input-output-lca
#14
Changqi Liu, Yaji Huang, Xinye Wang, Yang Tai, Lingqin Liu, Hao Liu
Studies on the environmental analysis of biofuels by fast pyrolysis and hydroprocessing (BFPH) have so far only focused on the environmental impacts from direct emissions and included few indirect emissions. The influence of ignoring some indirect emissions on the environmental performance of BFPH has not been well investigated and hence is not really understood. In addition, in order to avoid shifting environmental problems from one media to another, a comprehensive assessment of environmental impacts caused by the processes must quantify the environmental emissions to all media (air, water, and land) in relation to each life cycle stage...
August 10, 2017: Integrated Environmental Assessment and Management
https://www.readbyqxmd.com/read/28796345/photochemical-acceleration-of-dna-strand-displacement-using-ultrafast-dna-photo-cross-linking
#15
Shigetaka Nakamura, Hirokazu Hashimoto, Satoshi Kobayashi, Kenzo Fujimoto
DNA strand displacement is an essential reaction in genetic recombination, biological processes, and DNA nanotechnology. In our body, DNA strand displacement is regulated and accelerated by enzymes. Furthermore, acceleration of DNA strand displacement is required for a rapid response of biological processes. In this study, we evaluated the DNA strand displacement using DNA photo-cross-linking to accelerate this displacement. The DNA photo-cross-linking of CNVK was accelerated at least 20 times, showing a faster DNA strand displacement...
August 10, 2017: Chembiochem: a European Journal of Chemical Biology
https://www.readbyqxmd.com/read/28795751/stereospecific-photochemistry-of-%C3%AE-2-1-2-3-triazolines-in-solution-and-in-the-solid-state-scope-and-mechanistic-studies
#16
Tim S Chung, Yang Xue, Alberto Carranza, Miguel A Garcia-Garibay
The stereospecific photochemistry of ten N-aryl-substituted cis- or trans-Δ(2)-1,2,3-triazolines to form the corresponding cis- or trans-aziridines was investigated both in solution and in the solid-state. We found that photochemical reactions in the solid state are more stereospecific than in solution for the 8 crystalline Δ(2)-1,2,3-triazolines. Additionally, triplet sensitization for some triazolines results in triplet biradicals, which provide the more thermodynamically favored trans-aziridine regardless of the starting triazoline stereochemistry...
August 10, 2017: Photochemical & Photobiological Sciences
https://www.readbyqxmd.com/read/28793884/therapeutic-comparison-between-treatments-for-vulvar-lichen-sclerosus-study-protocol-of-a-randomized-prospective-and-controlled-trial
#17
Renata A Belotto, Maria Cristina Chavantes, João Paulo Tardivo, Roberto Euzébio Dos Santos, Raquel Civolani Marques Fernandes, Anna Carolina Ratto Tempestini Horliana, Christiane Pavani, Daniela Fátima Teixeira da Silva
BACKGROUND: Vulvar lichen sclerosus (VLS) is a lymphocyte-mediated disease of unknown etiology that can cause intense itching as well stenosis, hindering the evacuation and urination. It can also limit the sex life due to severe local pruritus, pain and dyspareunia (pain during sexual intercourse). The standard treatment for this disease is the use of topical corticosteroids to reduce the clinical symptoms and to try to increase disease-free intervals. Photodynamic therapy (PDT), a treatment that associates a light radiation with a photosensitizing agent and photobiomodulation (PBM) are therapies that can promote effective immunomodulatory responses at the application site by means of photophysical and photochemical phenomena from the molecular to the systemic level, which promote their use in chronic dermatoses...
August 10, 2017: BMC Women's Health
https://www.readbyqxmd.com/read/28793281/photosynthetic-limitation-and-mechanisms-of-photoprotection-under-drought-and-recovery-of-calotropis-procera-an-evergreen-c3-from-arid-regions
#18
Rebeca Rivas, Gabriella Frosi, Diego G Ramos, Silvia Pereira, Ana M Benko-Iseppon, Mauro G Santos
Calotropis procera is a C3 plant native from arid environmental zones. It is an evergreen, shrubby, non-woody plant with intense photosynthetic metabolism during the dry season. We measured photosynthetic parameters and leaf biochemical traits, such as gas exchange, photochemical parameters, A/Ci analysis, organic solutes, and antioxidant enzymes under controlled conditions in potted plants during drought stress, and following recovery conditions to obtain a better insight in the drought stress responses of C...
July 31, 2017: Plant Physiology and Biochemistry: PPB
https://www.readbyqxmd.com/read/28792660/photochemical-intramolecular-c-h-addition-of-dimesityl-hetero-arylboranes-via-a-1-6-sigmatropic-rearrangement
#19
Naoki Ando, Aiko Fukazawa, Tomokatsu Kushida, Yoshihito Shiota, Shuhei Itoyama, Kazunari Yoshizawa, Yasunori Matsui, Yutaro Kuramoto, Hiroshi Ikeda, Shigehiro Yamaguchi
A new reaction mode for triarylboranes under photochemical conditions was discovered. Photoirradiation of dimesitylboryl-substituted (hetero)arenes produced spirocyclic boraindanes, where one of the C-H bonds in the ortho-methyl groups of the mesityl substituents was formally added in a syn fashion to a C-C double bond of the (hetero)aryl group. Quantum chemical calculations and laser flash photolysis measurements indicated that the reaction proceeds via a [1,6]-sigmatropic rearrangement. This behavior is reminiscent of the photochemical reaction mode of arylalkenylketones, demonstrating the isosteric relation between tricoordinate organoboron compounds and the corresponding pseudo-carbocationic species in terms of pericyclic reactions...
August 9, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28792470/differential-mechanisms-of-photosynthetic-acclimation-to-light-and-low-temperature-in-arabidopsis-and-the-extremophile-eutrema-salsugineum
#20
Nityananda Khanal, Geoffrey E Bray, Anna Grisnich, Barbara A Moffatt, Gordon R Gray
Photosynthetic organisms are able to sense energy imbalances brought about by the overexcitation of photosystem II (PSII) through the redox state of the photosynthetic electron transport chain, estimated as the chlorophyll fluorescence parameter 1-qL, also known as PSII excitation pressure. Plants employ a wide array of photoprotective processes that modulate photosynthesis to correct these energy imbalances. Low temperature and light are well established in their ability to modulate PSII excitation pressure...
August 9, 2017: Plants (Basel, Switzerland)
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