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https://www.readbyqxmd.com/read/29145191/antioxidants-maintain-cellular-redox-homeostasis-by-elimination-of-reactive-oxygen-species
#1
Long He, Ting He, Shabnam Farrar, Linbao Ji, Tianyi Liu, Xi Ma
Reactive oxygen species (ROS) are produced by living cells as normal cellular metabolic byproduct. Under excessive stress conditions, cells will produce numerous ROS, and the living organisms eventually evolve series of response mechanisms to adapt to the ROS exposure as well as utilize it as the signaling molecules. ROS molecules would trigger oxidative stress in a feedback mechanism involving many biological processes, such as apoptosis, necrosis and autophagy. Growing evidences have suggested that ROS play a critical role as the signaling molecules throughout the entire cell death pathway...
November 17, 2017: Cellular Physiology and Biochemistry
https://www.readbyqxmd.com/read/29145035/controlled-stabilization-of-anionic-forms-of-the-uracil-derivatives-a-dft-study
#2
Margarita G Ilyina, Edward M Khamitov, Akhat G Mustafin, S L Khursan
Relative stabilities of the N1/N3/О5/О6 anions of 42 substituted uracils in gas phase and aqueous solutions have been theoretically studied using approximation IEFPCM (SMD) - TPSS/aug-cc-pVTZ. The specific solvation of uracil and its anions has been simulated with the first hydrate shell made up with 5 water molecules. The nonspecific solvation has been accounted in terms of the SMD model. We have found a series of relative stability under conditions of both specific and nonspecific hydration. The series is ranked according to the increase of the relative stability of the N3 anion...
November 11, 2017: Journal of Molecular Graphics & Modelling
https://www.readbyqxmd.com/read/29145017/membrane-interactions-of-microgels-as-carriers-of-antimicrobial-peptides
#3
Randi Nordström, Lina Nyström, Oliver C J Andrén, Michael Malkoch, Anita Umerska, Mina Davoudi, Artur Schmidtchen, Martin Malmsten
Microgels are interesting as potential delivery systems for antimicrobial peptides. In order to elucidate membrane interactions of such systems, we here investigate effects of microgel charge density on antimicrobial peptide loading and release, as well as consequences of this for membrane interactions and antimicrobial effects, using ellipsometry, circular dichroism spectroscopy, nanoparticle tracking analysis, dynamic light scattering and z-potential measurements. Anionic poly(ethyl acrylate-co-methacrylic acid) microgels were found to incorporate considerable amounts of the cationic antimicrobial peptides LL-37 (LLGDFFRKSKEKIGKEFKRIVQRIKDFLRNLVPRTES) and DPK-060 (GKHKNKGKKNGKHNGWKWWW) and to protect incorporated peptides from degradation by infection-related proteases at high microgel charge density...
November 6, 2017: Journal of Colloid and Interface Science
https://www.readbyqxmd.com/read/29144773/cancer-chemopreventive-antiproliferative-and-superoxide-anion-scavenging-properties-of-kluyveromyces-marxianus-and-saccharomyces-cerevisiae-var-boulardii-cell-wall-components
#4
Olivier Fortin, Blanca Aguilar-Uscanga, Khanh Dang Vu, Stephane Salmieri, Monique Lacroix
This study investigated the cancer chemopreventive, the antiradical, and the antiproliferative properties of polysaccharides extracts from cell wall of Saccharomyces boulardii and Kluyveromyces marxianus. β-glucan, mannan, and chitin were also quantified to identify the most important extract responsible for these biological properties. Soluble and insoluble glucans as well as mannoprotein were extracted from cell wall using single hot-alkaline method. Superoxide anion scavenging (antiradical capacity), NAD(P)H: quinone reductase (QR) (EC 1...
November 16, 2017: Nutrition and Cancer
https://www.readbyqxmd.com/read/29144761/amphiphiles-without-head-and-tail-design-nanostructures-based-on-the-self-assembly-of-anionic-boron-cluster-compounds
#5
Roberto Fernandez-Alvarez, Vladimír Ďorďovič, Mariusz Uchman, Pavel Matejicek
Anionic boron hydride cluster compounds (ABCCs) are intrinsically amphiphilic building blocks suitable for nanochemistry. ABCCs are involved in atypical weak interactions, notably dihydrogen bonding, due to their peculiar polyhedral structure, consisting of negatively charged B-H units. The most striking feature of ABCCs that differentiates them from typical surfactants is the lack of head-and-tail structure. Furthermore, their structure can be described as intrinsically amphiphilic or aquaneutral. Therefore, classical terms established to describe self-assembly of classical amphiphiles are insufficient and need to be reconsidered...
November 16, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/29144752/investigation-of-iodonium-trifluoroborate-zwitterions-as-bifunctional-arene-reagents
#6
Raphaël Robidas, Vincent Guérin, Laurent Provençal, Marco Echeverria, Claude Y Legault
The synthesis of a new family of iodonium zwitterions, in which the formal anion is a trifluoroborate moiety, is reported. These reagents present very good stability and have high resistance toward benzyne formation. Their structures were confirmed by X-ray crystallographic analysis and were further investigated using DFT calculations. QTAIM analysis supports an ionic, noncovalent, I(+)···BF3(-) interaction, in accordance with a true zwitterionic nature. Preliminary results of synthetic applications, the arylation of phenolates and trifluoroborate group functionalization, are reported...
November 16, 2017: Organic Letters
https://www.readbyqxmd.com/read/29144294/higher-alkyl-sulfatase-activity-required-by-microbial-inhabitants-to-remove-anionic-surfactants-in-the-contaminated-surface-waters
#7
Bulent Icgen, Salih Batuhan Salik, Lale Goksu, Huseyin Ulusoy, Fadime Yilmaz
Biodegradation of anionic surfactants, like sodium dodecyl sulfate (SDS) are challenged by some bacteria through the function of the enzyme alkyl sulfatases. Therefore, identifying and characterizing bacteria capable of degrading SDS with high alkyl sulfatase enzyme activity are pivotal. In this study, bacteria isolated from surfactant contaminated river water were screened for their potential to degrade SDS. Primary screening carried out by the conventional enrichment culture technique and assessment of SDS-degrading ability through methylene blue active substance assay revealed 12, out of 290, SDS-degrading surface water bacteria with maximum SDS degrading abilities of 46-94% in 24-54 h...
November 2017: Water Science and Technology: a Journal of the International Association on Water Pollution Research
https://www.readbyqxmd.com/read/29144143/study-of-the-hydrate-melt-li4ti5o12-interphase-by-scanning-electron-microscopy-based-spectroscopy
#8
Mitsunori Kitta, Noboru Tagichi, Chie Fukada, Masanori Kohyama
To develop safe and low-cost Li-ion batteries, recently, an aqueous-based electrolyte so-called "hydrate-melt" electrolyte is proposed. Li4Ti5O12 is a promising negative electrode material for a Li-ion battery with such a hydrate-melt electrolyte, because of its unexpected reversible Li-insertion and extraction properties without usually-inevitable water reduction. The solid-electrolyte interphase formation is one of the reasons for this stable reaction, while a detail analysis is not yet performed. Here, a Li4Ti5O12 electrode surface reacted in a hydrate-melt electrolyte is investigated by scanning electron microscopy based analysis...
November 16, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/29144009/immobilization-of-superoxide-dismutase-on-polyelectrolyte-functionalized-titania-nanosheets
#9
Paul Rouster, Marko Pavlovic, Istvan Szilagyi
Superoxide dismutase (SOD) enzyme was successfully immobilized on titania nanosheets (TNS) functionalized with poly(diallyldimethylammonium chloride) (PDADMAC) polyelectrolyte. The TNS-PDADMAC solid support was prepared by hydrothermal synthesis followed by self-assembled polyelectrolyte layer formation. It was found that the SOD strongly adsorbed on the oppositely charged TNS-PDADMAC through electrostatic and hydrophobic interactions. The TNS-PDADMAC-SOD material was characterized by light scattering and microscopy techniques...
November 16, 2017: Chembiochem: a European Journal of Chemical Biology
https://www.readbyqxmd.com/read/29143938/short-hairpin-rna-interference-targeting-interleukin-1-receptor-type-i-in-the-paraventricular-nucleus-attenuates-hypertension-in-rats
#10
Peng Lu, Shu-Jun Jiang, Hong Pan, Ai-Li Xu, Gui-Hua Wang, Chun-Lei Ma, Zhen Shi
Blood pressure is controlled by tonic sympathetic activities, excessive activation of which contributes to the pathogenesis and progression of hypertension. Interleukin (IL)-1β in the paraventricular nucleus (PVN) is involved in sympathetic overdrive and hypertension. Here, we investigated the therapeutic effects of IL-1 receptor type I (IL-1R1) gene silencing in the PVN on hypertension. Recombinant lentivirus vectors expressing a short hairpin RNA (shRNA) targeting IL-1R1 (Lv-shR-IL-1R1) or a control shRNA were microinjected into PVN of spontaneously hypertensive rats (SHRs) and normotensive WKY rats...
November 16, 2017: Pflügers Archiv: European Journal of Physiology
https://www.readbyqxmd.com/read/29143845/pulse-laser-induced-fragmentation-of-carbon-quantum-dots-a-structural-analysis
#11
Han-Wei Chu, Ju-Yi Mao, Chia-Wen Lien, Pang-Hung Hsu, Yu-Jia Li, Jui-Yang Lai, Tai-Chia Chiu, Chih-Ching Huang
Carbon quantum dots (CQDs) have attracted enormous interest in recent years owing to their low cytotoxicity, excellent biocompatibility and strong fluorescence. They have been successfully employed in sensor, bio-imaging, and drug carrier applications. A complete understanding of their core-surface structure is essential for tuning their physical and chemical properties for various applications. Conventional characterizations of CQDs are conducted with electron microscopy or spectroscopy, such as transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and Raman spectroscopy...
November 16, 2017: Nanoscale
https://www.readbyqxmd.com/read/29143758/determination-of-the-bridging-ligand-in-the-active-site-of-tyrosinase
#12
Congming Zou, Wei Huang, Gaokun Zhao, Xiao Wan, Xiaodong Hu, Yan Jin, Junying Li, Junjun Liu
Tyrosinase is a type-3 copper enzyme that is widely distributed in plants, fungi, insects, and mammals. Developing high potent inhibitors against tyrosinase is of great interest in diverse fields including tobacco curing, food processing, bio-insecticides development, cosmetic development, and human healthcare-related research. In the crystal structure of Agaricus bisporus mushroom tyrosinase, there is an oxygen atom bridging the two copper ions in the active site. It is unclear whether the identity of this bridging oxygen is a water molecule or a hydroxide anion...
October 28, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29143340/k2p-task-2-and-kcnq1-kcne3-k-channels-are-major-players-contributing-to-intestinal-anion-and-fluid-secretion
#13
Francisca Julio-Kalajzić, Sandra Villanueva, Johanna Burgos, Margarita Ojeda, L Pablo Cid, Thomas J Jentsch, Francisco V Sepúlveda
Anion and fluid secretion across the intestinal epithelium, a process altered in cystic fibrosis and secretory diarrhoea, is mediated by cAMP-activated CFTR Cl(-) channels and requires the simultaneous activity of basolateral K(+) channels to maintain cellular ionic homeostasis and membrane potential. This function is fulfilled by the cAMP-activated K(+) channel formed by the association of pore-forming KCNQ1 with its obligatory KCNE3 β-subunit. Studies using mice show sizable cAMP-activated intestinal anion secretion in the absence of either KCNQ1 or KCNE3 suggesting that an alternative K(+) conductance must compensate for the loss of KCNQ1/KCNE3 activity...
November 16, 2017: Journal of Physiology
https://www.readbyqxmd.com/read/29143242/comparing-reactive-oxygen-species-and-dna-fragmentation-in-semen-samples-of-unexplained-infertile-and-healthy-fertile-men
#14
Zahra Zandieh, Akram Vatannejad, Mahmood Doosti, Sara Zabihzadeh, Mahnaz Haddadi, Leila Bajelan, Batool Rashidi, Saeid Amanpour
BACKGROUND: Male factor infertility has increased to more than 40% during the last decade. About 30% of these couples are diagnosed with unexplained infertility. In fact, reactive oxygen species (ROS), especially superoxide anion (O2(-)·) and hydrogen peroxide (H2O2), play a crucial role in regulation of physiological and pathological processes in spermatozoa. Moreover, since the diagnosis of unexplained infertility just through semen analysis is a matter of much controversy; we aimed to evaluate the levels of ROS and sperm DNA fragmentation in the semen samples of unexplained infertile and fertile control couples...
November 15, 2017: Irish Journal of Medical Science
https://www.readbyqxmd.com/read/29143215/combining-cationic-and-anionic-mixed-mode-sorbents-in-a-single-cartridge-to-extract-basic-and-acidic-pharmaceuticals-simultaneously-from-environmental-waters
#15
Daniela Salas, Francesc Borrull, Núria Fontanals, Rosa Maria Marcé
The aim of the present study is to broaden the applications of mixed-mode ion-exchange solid-phase extraction sorbents to extract both basic and acidic compounds simultaneously by combining the sorbents in a single cartridge and developing a simplified extraction procedure. Four different cartridges containing negative and positive charges in the same configuration were evaluated and compared to extract a group of basic, neutral, and acidic pharmaceuticals selected as model compounds. After a thorough optimization of the extraction conditions, the four different cartridges showed to be capable of retaining basic and acidic pharmaceuticals simultaneously through ionic interactions, allowing the introduction of a washing step with 15 mL methanol to eliminate interferences retained by hydrophobic interactions...
November 15, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/29143022/high-co2-absorption-capacity-by-chemisorption-at-cations-and-anions-in-choline-based-ionic-liquids
#16
Shubhankar Bhattacharyya, Andrei Filippov, Faiz Ullah Shah
The effect of CO2 absorption on the aromaticity and hydrogen bonding in ionic liquids is investigated. Five different ionic liquids with choline based cations and aprotic N-heterocyclic anions were synthesized. Purity and structures of the synthesized ionic liquids were characterized by (1)H and (13)C NMR spectroscopy. CO2 capture performance was studied at 20 °C and 40 °C under three different pressures (1, 3, 6 bar). The IL [N1,1,6,2OH][4-Triz] showed the highest CO2 capture capacity (28.6 wt%, 1.57 mol of CO2 per mol of the IL, 6...
November 16, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/29142401/phytochemical-compositions-and-in-vitro-assessments-of-antioxidant-and-antidiabetic-potentials-of-fractions-from-ehretia-cymosa-thonn
#17
Akintayo Ogundajo, Anofi Tom Ashafa
Background: Ehretia cymosa Thonn. is a popular medicinal plant used in different parts of West Africa for the treatment of various ailments including diabetes mellitus. Objective: The current study investigates bioactive constituents and in vitro antioxidant and antidiabetic potentials of fractions from extract of E. cymosa. Materials and Methods: Phytochemical investigation and antioxidant assays were carried out using standard procedures...
October 2017: Pharmacognosy Magazine
https://www.readbyqxmd.com/read/29142222/human-atg3-binding-to-lipid-bilayers-role-of-lipid-geometry-and-electric-charge
#18
Javier H Hervás, Ane Landajuela, Zuriñe Antón, Anna V Shnyrova, Felix M Goñi, Alicia Alonso
Specific protein-lipid interactions lead to a gradual recruitment of AuTophaGy-related (ATG) proteins to the nascent membrane during autophagosome (AP) formation. ATG3, a key protein in the movement of LC3 towards the isolation membrane, has been proposed to facilitate LC3/GABARAP lipidation in highly curved membranes. In this work we have performed a biophysical study of human ATG3 interaction with membranes containing phosphatidylethanolamine, phosphatidylcholine and anionic phospholipids. We have found that ATG3 interacts more strongly with negatively-charged phospholipid vesicles or nanotubes than with electrically neutral model membranes, cone-shaped anionic phospholipids (cardiolipin and phosphatidic acid) being particularly active in promoting binding...
November 15, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29142208/transient-increases-in-intracellular-calcium-and-reactive-oxygen-species-levels-in-tcam-2-cells-exposed-to-microgravity
#19
C Morabito, S Guarnieri, A Catizone, C Schiraldi, G Ricci, M A Mariggiò
The effects of microgravity on functions of the human body are well described, including alterations in the male and female reproductive systems. In the present study, TCam-2 cells, which are considered a good model of mitotically active male germ cells, were used to investigate intracellular signalling and cell metabolism during exposure to simulated microgravity, a condition that affects cell shape and cytoskeletal architecture. After a 24 hour exposure to simulated microgravity, TCam-2 cells showed 1) a decreased proliferation rate and a delay in cell cycle progression, 2) increased anaerobic metabolism accompanied by increased levels of intracellular Ca(2+), reactive oxygen species and superoxide anion and modifications in mitochondrial morphology...
November 15, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29141721/coupling-ion-chromatography-to-q-orbitrap-for-the-fast-and-robust-analysis-of-anionic-pesticides-in-fruits-and-vegetables
#20
Łukasz Rajski, Francisco José Díaz Galiano, Víctor Cutillas, Amadeo R Fernández-Alba
Ion chromatography coupled to a quadrupole Orbitrap mass analyzer was used to develop a multiresidue method for the determination of highly polar pesticides and their metabolites (chlorate, perchlorate, fosetyl-aluminum, glyphosate, aminomethylphosphonic acid (AMPA), phosphonic acid, N-acetyl AMPA, and N-acetyl glyphosate) in fruits and vegetables. After extraction with methanol, samples were diluted 5× with water. No derivatization was applied. Pesticides were separated in an anion-exchange column. Water was used as the ion chromatography mobile phase...
November 15, 2017: Journal of AOAC International
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