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https://www.readbyqxmd.com/read/28545261/microbicidal-activity-of-n-chlorotaurine-in-combination-with-hydrogen-peroxide
#1
Jasmin Mustedanagic, Valdecir Farias Ximenes, Markus Nagl
N-chlorotaurine (NCT) and hydrogen peroxide are powerful endogenous antiseptics. In vivo, the reaction between hydrogen peroxide and metal ions leads to the formation of free hydroxyl radicals, which have an increased bactericidal activity. This study examined whether there is an additive antimicrobial effect of NCT combined with hydrogen peroxide. Additionally, it was tested if the additive effect is based on the formation of free radicals. We found by luminometry that, in the presence of H2O2, NCT caused a slow and long-lasting production of singlet oxygen in contrast to HOCl, where this burst occurred instantaneously...
December 2017: AMB Express
https://www.readbyqxmd.com/read/28545257/the-reactive-sulfur-species-concept-15-years-on
#2
REVIEW
Gregory I Giles, Muhammad Jawad Nasim, Wesam Ali, Claus Jacob
Fifteen years ago, in 2001, the concept of "Reactive Sulfur Species" or RSS was advocated as a working hypothesis. Since then various organic as well as inorganic RSS have attracted considerable interest and stimulated many new and often unexpected avenues in research and product development. During this time, it has become apparent that molecules with sulfur-containing functional groups are not just the passive "victims" of oxidative stress or simple conveyors of signals in cells, but can also be stressors in their own right, with pivotal roles in cellular function and homeostasis...
May 23, 2017: Antioxidants (Basel, Switzerland)
https://www.readbyqxmd.com/read/28545243/ficus-umbellata-vahl-moraceae-stem-bark-extracts-exert-antitumor-activities-in-vitro-and-in-vivo
#3
Kevine Kamga Silihe, Stéphane Zingue, Evelyn Winter, Charline Florence Awounfack, Anupam Bishayee, Nishil N Desai, Leônidas João Mello, Thomas Michel, Francine Nzufo Tankeu, Derek Tantoh Ndinteh, Sara Honorine Riwom, Dieudonné Njamen, Tânia Beatriz Creczynski-Pasa
A Ficus umbellata is used to treat cancer. The present work was therefore designed to assess antitumor potentials of F. umbellata extracts in nine different cell lines. Cell cycle, apoptosis, cell migration/invasion, levels of reactive oxygen species (ROS), mitochondrial membrane potential (MMP), caspases activities as well as Bcl-2 and Bcl-xL protein content were assessed in MDA-MB-231 cells. The 7,12-dimethylbenz(a)anthracene (DMBA)-induced carcinogenesis in rats were also used to investigate antitumor potential of F...
May 23, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/28545214/sediment-carbon-and-nutrient-fluxes-from-cleared-and-intact-temperate-mangrove-ecosystems-and-adjacent-sandflats
#4
Richard H Bulmer, Luitgard Schwendenmann, Andrew M Lohrer, Carolyn J Lundquist
The loss of mangrove ecosystems is associated with numerous impacts on coastal and estuarine function, including sediment carbon and nutrient cycling. In this study we compared in situ fluxes of carbon dioxide (CO2) from the sediment to the atmosphere, and fluxes of dissolved inorganic nutrients and oxygen across the sediment-water interface, in intact and cleared mangrove and sandflat ecosystems in a temperate estuary. Measurements were made 20 and 25months after mangrove clearance, in summer and winter, respectively...
May 21, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28545211/nano-enabling-of-strong-base-ion-exchange-media-via-a-room-temperature-aluminum-hydr-oxide-synthesis-method-to-simultaneously-remove-nitrate-and-fluoride
#5
Jasmina Markovski, Jose Garcia, Kiril D Hristovski, Paul Westerhoff
This study demonstrated a new room-temperature method for synthesizing aluminum (hydr)oxide material inside the pores of strong-base ion-exchange resin to fabricate a novel class of hybrid media capable of simultaneously removing nitrate and fluoride as model groundwater contaminants. The aluminum (hydr)oxide hybrid media was fabricated by reducing aluminum ion precursors with borohydride within ion-exchange resin at room temperature, followed by exposure to environmental oxygen. The hybrid media was characterized, and its performance to simultaneously remove nitrate and fluoride was determined in simple and complex water matrices using short-bed column tests operated under conditions realistic for point-of-use systems...
May 20, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28545210/response-of-microcystis-aeruginosa-bccusp-232-to-barley-hordeum-vulgare-l-straw-degradation-extract-and-fractions
#6
Gustavo Franciscatti Mecina, Anne Lígia Dokkedal, Luiz Leonardo Saldanha, Mathias Ahii Chia, Micheline Kézia Cordeiro-Araújo, Maria do Carmo Bittencourt-Oliveira, Regildo Márcio Gonçalves da Silva
The eutrophication of aquatic ecosystems is a serious environmental problem that leads to increased frequency of cyanobacterial blooms and concentrations of cyanotoxins. These changes in aquatic chemistry can negatively affect animal and human health. Environment-friendly methods are needed to control bloom forming cyanobacteria. We investigated the effect of Hordeum vulgare L. (barley) straw degradation extract and its fractions on the growth, oxidative stress, antioxidant enzyme activities, and microcystins content of Microcystis aeruginosa (Kützing) Kützing BCCUSP232...
May 20, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28545188/clinacanthus-nutans-hexane-extracts-induce-apoptosis-through-a-caspase-dependent-pathway-in-human-cancer-cell-lines
#7
Pei Ying Ng, Soi Moi Chye, Chew Hee Ng, Rhun Yian Koh, Yee Lian Tiong, Liew Phing Pui, Yong Hui Tan, Crystale Siew Ying Lim, Khuen Yen Ng
Background: Clinacanthus nutans (C.nutans) is a plant consumed as a cancer treatment in tropical Asia. Despite the availability of numerous anecdotal reports, evaluation of active anticancer effects has remained elusive. Therefore we here examined antiproliferative, reactive oxygen species (ROS)-inducing and apoptosis mechanisms of whole plant extracts in different cancer cell lines. Methods: Antiproliferative actions of five solvent extracts (hexane, chloroform, ethyl acetate, methanol and water) of C.nutans were tested on non-small cell lung cancer (A549), nasopharygeal cancer (CNE1) and liver cancer (HepG2) cells using MTT assay...
April 1, 2017: Asian Pacific Journal of Cancer Prevention: APJCP
https://www.readbyqxmd.com/read/28545126/pheromone-sensing-neurons-regulate-peripheral-lipid-metabolism-in-caenorhabditis-elegans
#8
Rosalind Hussey, Jon Stieglitz, Jaleh Mesgarzadeh, Tiffany T Locke, Ying K Zhang, Frank C Schroeder, Supriya Srinivasan
It is now established that the central nervous system plays an important role in regulating whole body metabolism and energy balance. However, the extent to which sensory systems relay environmental information to modulate metabolic events in peripheral tissues has remained poorly understood. In addition, it has been challenging to map the molecular mechanisms underlying discrete sensory modalities with respect to their role in lipid metabolism. In previous work our lab has identified instructive roles for serotonin signaling as a surrogate for food availability, as well as oxygen sensing, in the control of whole body metabolism...
May 18, 2017: PLoS Genetics
https://www.readbyqxmd.com/read/28545109/hyperbaric-oxygen-therapy-for-wound-healing-in-diabetic-rats-varying-efficacy-after-a-clinically-based-protocol
#9
Johan W van Neck, Bastiaan Tuk, Esther M G Fijneman, Jonathan J Redeker, Edwin M Talahatu, Miao Tong
Hyperbaric oxygen therapy (HBOT) is a clinical treatment in which a patient breathes pure oxygen for a limited period of time at an increased pressure. Although this therapy has been used for decades to assist wound healing, its efficacy for many conditions is unproven and its mechanism of action is not yet fully clarified. This study investigated the effects of HBOT on wound healing using a diabetes-impaired pressure ulcer rat model. Seven weeks after streptozotocin-induced diabetes in rats (n = 55), a pressure ulcer was created on dorsal skin...
2017: PloS One
https://www.readbyqxmd.com/read/28545088/transcriptional-activation-of-hif-1-by-a-ros-erk-axis-underlies-the-resistance-to-photodynamic-therapy
#10
María Julia Lamberti, María Florencia Pansa, Renzo Emanuel Vera, Martín Ernesto Fernández-Zapico, Natalia Belén Rumie Vittar, Viviana Alicia Rivarola
Photodynamic therapy (PDT), a promising treatment option for cancer, involves the activation of a photosensitizer (PS) by local irradiation with visible light. Excitation of the PS leads to a series of photochemical reactions and consequently the local generation of harmful reactive oxygen species (ROS) causing limited or none systemic defects. However, the development of resistance to this promising therapy has slowed down its translation into the clinical practice. Thus, there is an increase need in understanding of the molecular mechanism underlying resistance to PDT...
2017: PloS One
https://www.readbyqxmd.com/read/28545086/cancer-cell-spheroids-are-a-better-screen-for-the-photodynamic-efficiency-of-glycosylated-photosensitizers
#11
Patrícia M R Pereira, Naxhije Berisha, N V S Dinesh K Bhupathiraju, Rosa Fernandes, João P C Tomé, Charles Michael Drain
Photodynamic Therapy (PDT) relies on the use of non-toxic photosensitizers that are locally and selectively activated by light to induce cell death or apoptosis through reactive oxygen species generation. The conjugation of porphyrinoids with sugars that target cancer is increasingly viewed as an effective way to increase the selectivity of PDT. To date, in vitro PDT efficacy is mostly screened using two-dimensional monolayer cultures. Compared to monolayer cultures, three-dimensional spheroid cultures have unique spatial distributions of nutrients, metabolites, oxygen and signalling molecules; therefore better mimic in vivo conditions...
2017: PloS One
https://www.readbyqxmd.com/read/28544980/what-we-authors-reviewers-and-editors-of-scientific-work-can-learn-from-the-analytical-history-of-biological-3-nitrotyrosine
#12
REVIEW
Dimitrios Tsikas
Tyrosine and tyrosine residues in proteins are attacked by the reactive oxygen and nitrogen species peroxynitrite (O=N-OO(-)) to generate 3-nitrotyrosine (3-NT) and 3-nitrotyrosine-proteins (3-NTProt), respectively. 3-NT and 3-NTProt are widely accepted as biomarkers of nitr(os)ative stress. Over the years many different analytical methods have been reported for 3-NT and 3-NTProt. Reported concentrations often differ by more than three orders of magnitude, indicative of serious analytical problems. Strategies to overcome pre-analytical and analytical shortcomings and pitfalls have been proposed...
May 13, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28544937/recycling-metals-from-lithium-ion-battery-by-mechanical-separation-and-vacuum-metallurgy
#13
Jiefeng Xiao, Jia Li, Zhengming Xu
The large-batch application of lithium ion batteries leads to the mass production of spent batteries. So the enhancement of disposal ability of spent lithium ion batteries is becoming very urgent. This study proposes an integrated process to handle bulk spent lithium manganese (LiMn2O4) batteries to in situ recycle high value-added products without any additives. By mechanical separation, the mixed electrode materials mainly including binder, graphite and LiMn2O4 are firstly obtained from spent batteries. Then, the reaction characteristics for the oxygen-free roasting of mixed electrode materials are analyzed...
May 17, 2017: Journal of Hazardous Materials
https://www.readbyqxmd.com/read/28544928/achieving-advanced-nitrogen-removal-for-small-flow-wastewater-using-a-baffled-bioreactor-bbr-with-intermittent-aeration
#14
Guoqiang Liu, Jianmin Wang
Nitrogen discharge from decentralized and onsite wastewater treatment systems, such as recirculating sand filters, stabilization ponds, and septic tanks, is an important source of groundwater and surface water contamination. This study demonstrated a simple baffled bioreactor (BBR) technology, operated with an intermittent aeration mode, that effectively removed nearly all nitrogen for small flow wastewater treatment. The BBR is characterized by an aeration zone, followed by an integrated internal settler, which automatically retains a high biomass concentration of approximately 6 g/L without using a separate sludge return device...
May 22, 2017: Journal of Environmental Management
https://www.readbyqxmd.com/read/28544901/alkaline-electrochemical-advanced-oxidation-process-for-chromium-oxidation-at-graphitized-multi-walled-carbon-nanotubes
#15
Yudong Xue, Shili Zheng, Zhi Sun, Yi Zhang, Wei Jin
Alkaline electrochemical advanced oxidation processes for chromium oxidation and Cr-contaminated waste disposal were reported in this study. The highly graphitized multi-walled carbon nanotubes g-MWCNTs modified electrode was prepared for the in-situ electrochemical generation of HO2(-). RRDE test results illustrated that g-MWCNTs exhibited much higher two-electron oxygen reduction activity than other nanocarbon materials with peak current density of 1.24 mA cm(-2), %HO2(-) of 77.0% and onset potential of -0...
May 20, 2017: Chemosphere
https://www.readbyqxmd.com/read/28544744/structural-basis-for-copper-oxygen-mediated-c-h-bond-activation-by-the-formylglycine-generating-enzyme
#16
Marcel Meury, Matthias Knop, Florian P Seebeck
The formylglycine-generating enzyme (FGE) is a unique copper-protein that catalyzes oxygen-dependent C-H activation. We describe 1.66 Å- and 1.28 Å-resolution crystal structures of FGE from Thermomonospora curvata in complex with either Ag (I) or Cd (II) providing definitive evidence for a high-affinity metal-binding site in this enzyme. The structures reveal a bis-cysteine linear coordination of the monovalent metal, and tetrahedral coordination of the bivalent metal. Similar coordinational change may occur in the active enzyme as a result of Cu (I)/(II) redox cycling...
May 22, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28544665/humidified-high-flow-nasal-cannula-oxygen-in-bronchiolitis-reduces-need-for-invasive-ventilation-but-not-intensive-care-admission
#17
Chong Tien Goh, Lynette J Kirby, David N Schell, Jonathan R Egan
AIM: To describe the changes to paediatric intensive care unit (PICU) admission patterns and ventilation requirements for children with bronchiolitis following the introduction of humidified high-flow nasal cannula oxygen outside the PICU. METHODS: Retrospective study comparing patients <24 months of age with a discharge diagnosis of bronchiolitis admitted to the PICU. A comparison was made between those before humidified high-flow nasal cannula oxygen use (year 2008) to those immediately following the introduction of humidified high-flow nasal cannula oxygen use (year 2011) and those following further consolidation of humidified high-flow nasal cannula oxygen use outside the PICU (year 2013)...
May 23, 2017: Journal of Paediatrics and Child Health
https://www.readbyqxmd.com/read/28544652/brownmillerite-type-ca2fecoo5-as-a-practicable-oxygen-evolution-reaction-catalyst
#18
Etsushi Tsuji, Teruki Motohashi, Hiroyuki Noda, Damian Kowalski, Yoshitaka Aoki, Hajime Tanida, Junji Niikura, Yukinori Koyama, Masahiro Mori, Hajime Arai, Tsutomu Ioroi, Naoko Fujiwara, Yoshiharu Uchimoto, Zempachi Ogumi, Hiroki Habazaki
Here, we report remarkable oxygen evolution reaction (OER) catalytic activity of brownmillerite (BM)-type Ca2FeCoO5. The OER activity of this oxide is comparable to or beyond those of the state-of-the-art perovskite (PV)-catalyst Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF) and a precious-metal catalyst RuO2, emphasizing the importance of the characteristic BM structure with multiple coordination environments of transition metal (TM) species. Also, Ca2FeCoO5 is obviously advantageous in terms of expense/laboriousness of the material synthesis...
May 25, 2017: ChemSusChem
https://www.readbyqxmd.com/read/28544643/adaptations-to-endurance-training-depend-on-exercise-induced-oxidative-stress-exploiting-redox-inter-individual-variability
#19
Nikos V Margaritelis, Anastasios A Theodorou, Vassilis Paschalis, Aristidis S Veskoukis, Konstantina Dipla, Andreas Zafeiridis, George Panayiotou, Ioannis S Vrabas, Antonios Kyparos, Michalis G Nikolaidis
AIM: The aim of the present study was to reveal the role of reactive oxygen and nitrogen species (RONS) in exercise adaptations under physiological in vivo conditions and without the interference from other exogenous redox agents (e.g., a pro-oxidant or antioxidant). METHODS: We invented a novel methodological set-up that exploited the large redox inter-individual variability in exercise responses. More specifically, we used exercise-induced oxidative stress as the "classifier" measure (i...
May 24, 2017: Acta Physiologica
https://www.readbyqxmd.com/read/28544624/pyrimidine-containing-epidermal-growth-factor-receptor-kinase-inhibitors-synthesis-and-biological-evaluation
#20
Gaurav Joshi, Himanshu Nayyar, Sourav Kalra, Praveen Sharma, Anjana Munshi, Sandeep Singh, Raj Kumar
Structure based design and synthesis of pyrimidine containing reversible epidermal growth factor receptor (EGFR) inhibitors 1a-d are reported. The compounds (1a-d) inhibited the EGFR kinase activity in vitro with IC50 range 740 nM to 3 μM. mRNA expression of EGFR downstream target genes i.e. twist, c-fos and aurora were found to be altered upon treatment with compounds 1a-d. The compounds 1a-d exhibited excellent anticancer activity at low micromolar level (3.2-9 μM) in lung, colon and breast cancer cell lines...
May 23, 2017: Chemical Biology & Drug Design
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