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https://www.readbyqxmd.com/read/29161662/deiodination-of-iopamidol-by-zero-valent-iron-zvi-enhances-formation-of-iodinated-disinfection-by-products-during-chloramination
#1
Huiyu Dong, Zhimin Qiang, Junfeng Lian, Jin Li, Jianwei Yu, Jiuhui Qu
Iodinated X-ray contrast media (ICM) is considered as one of iodine sources for formation of toxic iodinated disinfection byproducts (I-DBPs) during disinfection. This study investigated transformation of a typical ICM, iopamidol (IPM) by zero valent iron (ZVI) and the effect of transformation on the formation of I-DBPs during chloramination. It was found that the presence of ZVI could deiodinate IPM into I(-) and the transformation of IPM exhibited a pseudo-first-order kinetics. Acidic circumstance, SO4(2-), Cl(-) and monochloramine could promote the transformation of IPM by ZVI, while SiO3(2-) inhibited the transformation of IPM...
November 14, 2017: Water Research
https://www.readbyqxmd.com/read/29158256/heart-failure-induced-activation-of-phospholipase-ipla2%C3%AE-%C3%A2-generates-hydroxyeicosatetraenoic-acids-opening-the-mitochondrial-permeability-transition-pore
#2
Sung Ho Moon, Xinping Liu, Ari M Cedars, Kui Yang, Michael A Kiebish, Susan M Joseph, John Kelley, Christopher M Jenkins, Richard W Gross
Congestive heart failure typically arises from cardiac myocyte necrosis/apoptosis, associated with the pathological opening of the mitochondrial permeability transition pore (mPTP). mPTP opening decreases the mitochondrial membrane potential leading to the activation of Ca(2+)-independent phospholipase A2γ (iPLA2γ) and the production of downstream toxic metabolites. However, the array of enzymatic mediators and the exact chemical mechanisms responsible for modulating myocardial mPTP opening remain unclear...
November 20, 2017: Journal of Biological Chemistry
https://www.readbyqxmd.com/read/29158084/distinct-expression-patterns-of-flk1-and-flt1-in-the-coronary-vascular-system-during-development-and-after-myocardial-infarction
#3
Shota Kurotsu, Rina Osakabe, Mari Isomi, Fumiya Tamura, Taketaro Sadahiro, Naoto Muraoka, Hidenori Kojima, Sho Haginiwa, Hidenori Tani, Kaori Nara, Yoshiaki Kubota, Masatsugu Ema, Keiichi Fukuda, Takeshi Suzuki, Masaki Ieda
The coronary vascular system is critical for myocardial growth and cardiomyocyte survival. However, the molecular mechanism regulating coronary angiogenesis remains elusive. Vascular endothelial growth factor (VEGF) regulates angiogenesis by binding to the specific receptors Flk1 and Flt1, which results in different functions. Despite the importance of Flk1 and Flt1, their expression in the coronary vasculature remains largely unknown due to the lack of appropriate antibodies for immunostaining. Here, we analyzed multiple reporter mice including Flk1-GFP BAC transgenic (Tg), Flk1-LacZ knock-in, Flt1-DsRed BAC Tg, and Flk1-GFP/Flt1-DsRed double Tg animals to determine expression patterns in mouse hearts during cardiac growth and after myocardial infarction (MI)...
November 17, 2017: Biochemical and Biophysical Research Communications
https://www.readbyqxmd.com/read/29157491/monitoring-protein-folding-through-high-pressure-nmr-spectroscopy
#4
REVIEW
Julien Roche, Catherine A Royer, Christian Roumestand
High-pressure is a well-known perturbation method used to destabilize globular proteins. It is perfectly reversible, which is essential for a proper thermodynamic characterization of a protein equilibrium. In contrast to other perturbation methods such as heat or chemical denaturant that destabilize protein structures uniformly, pressure exerts local effects on regions or domains of a protein containing internal cavities. When combined with NMR spectroscopy, hydrostatic pressure offers the possibility to monitor at a residue level the structural transitions occurring upon unfolding and to determine the kinetic properties of the process...
November 2017: Progress in Nuclear Magnetic Resonance Spectroscopy
https://www.readbyqxmd.com/read/29156293/fe-iii-sulfide-interaction-in-globins-characterization-and-quest-for-a-putative-fe-iv-sulfide-species
#5
Augustin C Mot, Cristina Bischin, Grigore Damian, Amr A A Attia, Emese Gal, Nicoleta Dina, Nicolae Leopold, Radu Silaghi-Dumitrescu
The present study reports findings regarding the contrast between H2S interaction with bovine hemoglobin (Hb) and horse heart myoglobin (Mb), in terms of binding and dissociation kinetics, affinities, and mechanism. At pH9.5, oxidation of ferric-sulfide adducts in presence of no free sulfide, using hexachloroiridate as oxidant is examined using stopped-flow UV-vis, EPR, vibrational spectroscopy and mass spectrometry. Oxidation of the ferric-sulfide adduct in such conditions occurs with a putative unstable Fe(IV)-sulfide adduct as intermediate that finally leads to a paramagnetic ferric species with distinct EPR features...
November 10, 2017: Journal of Inorganic Biochemistry
https://www.readbyqxmd.com/read/29155710/dna-nanotubes-as-a-versatile-tool-to-study-semiflexible-polymers
#6
Jörg Schnauß, Martin Glaser, Jessica S Lorenz, Carsten Schuldt, Christin Möser, Martin Sajfutdinow, Tina Händler, Josef A Käs, David M Smith
Mechanical properties of complex, polymer-based soft matter, such as cells or biopolymer networks, can be understood in neither the classical frame of flexible polymers nor of rigid rods. Underlying filaments remain outstretched due to their non-vanishing backbone stiffness, which is quantified via the persistence length (lp), but they are also subject to strong thermal fluctuations. Their finite bending stiffness leads to unique, non-trivial collective mechanics of bulk networks, enabling the formation of stable scaffolds at low volume fractions while providing large mesh sizes...
October 25, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/29154415/persistent-high-blood-urea-nitrogen-level-is-associated-with-increased-risk-of-cardiovascular-events-in-patients-with-acute-heart-failure
#7
Kentaro Jujo, Yuichiro Minami, Shintaro Haruki, Yuya Matsue, Kensuke Shimazaki, Hiromu Kadowaki, Issei Ishida, Keigo Kambayashi, Hiroyuki Arashi, Haruki Sekiguchi, Nobuhisa Hagiwara
AIMS: The association between kinetics of blood urea nitrogen (BUN) levels in hospital and cardiovascular outcomes in patients with acutely decompensated congestive heart failure (HF) is unclear. We aimed to estimate the impact of changes in BUN level during hospitalization on clinical prognosis in patients with acute HF. METHODS AND RESULTS: A total of 353 consecutive patients that were urgently hospitalized due to acutely decompensated HF and discharged alive were divided into four subgroups depending on their BUN level at admission and discharge, using a cut-off level of 21...
November 2017: ESC Heart Failure
https://www.readbyqxmd.com/read/29153904/comparison-of-cellulose-vs-plastic-cigarette-filter-decomposition-under-distinct-disposal-environments
#8
François-Xavier Joly, Mathieu Coulis
It is estimated that 4.5 trillion cigarette butts are discarded annually, making them numerically the most common type of litter on Earth. To accelerate their disappearance after disposal, a new type of cigarette filters made of cellulose, a readily biodegradable compound, has been introduced in the market. Yet, the advantage of these cellulose filters over the conventional plastic ones (cellulose acetate) for decomposition, remains unknown. Here, we compared the decomposition of cellulose and plastic cigarettes filters, either intact or smoked, on the soil surface or within a composting bin over a six-month field decomposition experiment...
November 15, 2017: Waste Management
https://www.readbyqxmd.com/read/29151177/mechanisms-of-drought-induced-dissipation-of-excitation-energy-in-sun-and-shade-adapted-drought-tolerant-mosses-studied-by-fluorescence-yield-change-and-global-and-target-analysis-of-fluorescence-decay-kinetics
#9
Hisanori Yamakawa, Ivo H M van Stokkum, Ulrich Heber, Shigeru Itoh
Some mosses stay green and survive long even under desiccation. Dissipation mechanisms of excess excitation energy were studied in two drought-tolerant moss species adapted to contrasting niches: shade-adapted Rhytidiadelphus squarrosus and sun-adapted Rhytidium rugosum in the same family. (1) Under wet conditions, a light-induced nonphotochemical quenching (NPQ) mechanism decreased the yield of photosystem II (PSII) fluorescence in both species. The NPQ extent saturated at a lower illumination intensity in R...
November 18, 2017: Photosynthesis Research
https://www.readbyqxmd.com/read/29149900/immunogenic-potential-of-a-salmonella-typhimurium-live-vaccine-for-pigs-against-monophasic-salmonella-typhimurium-dt-193
#10
Tobias Theuß, Elke Ueberham, Jörg Lehmann, Thomas Lindner, Sven Springer
BACKGROUND: Monophasic Salmonella Typhimurium (mSTM) strains account for up to 8.6% of all human Salmonellosis cases. They have an increasing prevalence during recent years and several human cases with hospitalisation were reported. These strains are often isolated from pigs and pork - one primary source of human infection. A Salmonella Typhimurium (STM) live vaccine has been proven successful in controlling of STM infections in pigs for many years. The aim of this study was to test the immunogenicity of the vaccine in weaners during oral challenge with a virulent mSTM strain and to examine the kinetics of STM-specific IgA, IgM and IgG antibodies induced by vaccination and infection...
November 17, 2017: BMC Veterinary Research
https://www.readbyqxmd.com/read/29147556/mechanism-of-biosurfactant-adsorption-to-oil-water-interfaces-from-millisecond-scale-tensiometry-measurements
#11
Lingling Kong, Kadi Liis Saar, Raphael Jacquat, Liu Hong, Aviad Levin, Hongze Gang, Ruqiang Ye, Bozhong Mu, Tuomas P J Knowles
Many biological molecules are by their nature amphiphilic and have the ability to act as surfactants, stabilizing interfaces between aqueous and immiscible oil phases. In this paper, we explore the adsorption kinetics of surfactin, a naturally occurring cyclic lipopeptide, at hexadecane/water interfaces and compare and contrast its adsorption behaviour with that of synthetic alkyl benzene sulfonate isomers, through direct measurements of changes in interfacial tension upon surfactant adsorption. We access millisecond time resolution in kinetic measurements by making use of droplet microfluidics to probe the interfacial tension of hexadecane droplets dispersed in a continuous water phase through monitoring their deformation when the droplets are exposed to shear flows in a microfluidic channel with regular corrugations...
December 6, 2017: Interface Focus
https://www.readbyqxmd.com/read/29147547/multi-dimensional-charge-transport-in-supramolecular-helical-foldamer-assemblies
#12
Alejandro Méndez-Ardoy, Nagula Markandeya, Xuesong Li, Yu-Tang Tsai, Gilles Pecastaings, Thierry Buffeteau, Victor Maurizot, Luca Muccioli, Frédéric Castet, Ivan Huc, Dario M Bassani
Aromatic foldamers are bioinspired architectures whose potential use in materials remains largely unexplored. Here we report our investigation of vertical and horizontal charge transport over long distances in helical oligo-quinolinecarboxamide foldamers organized as single monolayers on Au or SiO2. Conductive atomic force microscopy showed that vertical conductivity is efficient and that it displays a low attenuation with foldamer length (0.06 Å(-1)). In contrast, horizontal charge transport is found to be negligible, demonstrating the strong anisotropy of foldamer monolayers...
October 1, 2017: Chemical Science
https://www.readbyqxmd.com/read/29146210/novel-intracellular-transport-refractory-mutations-in-kcnh2-identified-in-patients-with-symptomatic-long-qt-syndrome
#13
Daisuke Fukumoto, Wei-Guang Ding, Yuko Wada, Yusuke Fujii, Mari Ichikawa, Koichiro Takayama, Megumi Fukuyama, Koichi Kato, Hideki Itoh, Takeru Makiyama, Mariko Omatsu-Kanbe, Hiroshi Matsuura, Minoru Horie, Seiko Ohno
BACKGROUND: Missense mutations in KCNH2, a gene encoding the Kv11.1 channel, cause long QT syndrome (LQTS) type 2 primarily by disrupting the intracellular transport of Kv11.1 to the plasma membrane. The present study aimed to clarify the functional changes by two novel KCNH2 missense mutations. METHODS: We performed genetic screening of three unrelated symptomatic LQTS probands with family histories of cardiac symptoms. Chinese hamster ovary cells were transfected with wild-type (WT) and/or mutant KCNH2 plasmid and examined by patch-clamp technique...
November 13, 2017: Journal of Cardiology
https://www.readbyqxmd.com/read/29144983/albumin-coordinated-assembly-of-clearable-platinum-nanodots-for-photo-induced-cancer-theranostics
#14
Yong'an Tang, Tao Yang, Qiaoli Wang, Xiaoyan Lv, Xue Song, Hengte Ke, Zhengqing Guo, Xiaoqing Huang, Jun Hu, Zifu Li, Peng Yang, Xiangliang Yang, Huabing Chen
Photoactive noble metal nanoparticles are of increasing importance toward personalized cancer therapy in the field of precision nanomedicine. A critical challenge remains in the exploration of clinically potential noble metal nanoparticles for highly efficient cancer theranostics. Here, we introduce albumin-coordinated assembly of clearable Pt nanodots (Pt-NDs) with monodisperse nanostructure as high-performance theranostic agents for imaging-guided photothermal tumor ablation. We precisely manipulate the reduction and growth of tetravalent Pt ions into ultrasmall nanodots through albumin-directed growth kinetics, thereby leading to the synthesis of monodisperse 6...
October 20, 2017: Biomaterials
https://www.readbyqxmd.com/read/29139577/copper-uptake-patterns-of-bioaccumulation-and-effects-in-glochidia-larvae-of-the-freshwater-mussel-lampsilis-cardium
#15
Marianna Basso Jorge, Adalto Bianchini, Chris M Wood, Patricia L Gillis
The early life stages of freshwater mussels are particularly sensitive to Cu contamination. We measured the acute toxicity, bioaccumulation and sublethal effects of Cu in glochidia. Additionally, we used radiolabeled Cu ((64) Cu) to examine the time-dependent kinetics of uptake over 24 h. (64) Cu uptake by live and dead glochidia exposed to 0.11 μmol/L exhibited similar hyperbolic patterns over the first 40 min, indicating an adsorptive phase independent of larval metabolism. Thereafter, uptake was linear with time, with a 10-fold lower bioaccumulation rate in live than in dead animals, representing a close to steady state of Cu regulation...
November 15, 2017: Environmental Toxicology and Chemistry
https://www.readbyqxmd.com/read/29138299/induction-of-antiviral-immune-response-through-recognition-of-the-repeating-subunit-pattern-of-viral-capsids-is-toll-like-receptor-2-dependent
#16
Kelly M Shepardson, Benjamin Schwarz, Kyle Larson, Rachelle V Morton, John Avera, Kimberly McCoy, Alayna Caffrey, Ann Harmsen, Trevor Douglas, Agnieszka Rynda-Apple
Although viruses and viral capsids induce rapid immune responses, little is known about viral pathogen-associated molecular patterns (PAMPs) that are exhibited on their surface. Here, we demonstrate that the repeating protein subunit pattern common to most virus capsids is a molecular pattern that induces a Toll-like-receptor-2 (TLR2)-dependent antiviral immune response. This early antiviral immune response regulates the clearance of subsequent bacterial superinfections, which are a primary cause of morbidities associated with influenza virus infections...
November 14, 2017: MBio
https://www.readbyqxmd.com/read/29136193/early-first-trimester-uteroplacental-flow-and-the-progressive-disintegration-of-spiral-artery-plugs-new-insights-from-contrast-enhanced-ultrasound-and-tissue-histopathology
#17
V H J Roberts, T K Morgan, P Bednarek, M Morita, G J Burton, J O Lo, A E Frias
STUDY QUESTION: Does the use of a vascular contrast agent facilitate earlier detection of maternal flow to the placental intervillous space (IVS) in the first trimester of pregnancy? SUMMARY ANSWER: Microvascular filling of the IVS was demonstrated by contrast-enhanced ultrasound from 6 weeks of gestation onwards, earlier than previously believed. WHAT IS KNOWN ALREADY: During placental establishment and remodeling of maternal spiral arteries, endovascular trophoblast cells invade and accumulate in the lumen of these vessels to form 'trophoblast plugs'...
November 10, 2017: Human Reproduction
https://www.readbyqxmd.com/read/29134458/animal-cell-expression-systems
#18
M Butler, Ing U Reichl
The glycan profile of therapeutic recombinant proteins such as monoclonal antibodies is a critical quality attribute, which affects the efficacy of the final product. The cellular glycosylation process during protein expression is dependent upon a number of factors such as the availability of substrates in the media, the intracellular content of nucleotide sugars, and the enzyme repertoire of the host cells. In order to control the variability of glycosylation it is important to understand the critical process parameters and their acceptable range of values to enable reproducible production of proteins with a predetermined glycan profile providing the desired biological function or therapeutic effect...
October 3, 2017: Advances in Biochemical Engineering/biotechnology
https://www.readbyqxmd.com/read/29134220/non-contact-electric-potential-measurements-of-electrode-components-in-an-operating-polymer-electrolyte-fuel-cell-by-near-ambient-pressure-xps
#19
Liwei Yu, Yasumasa Takagi, Takahiro Nakamura, Oki Sekizawa, Tomohiro Sakata, Tomoya Uruga, Mizuki Tada, Yasuhiro Iwasawa, Gabor Samjeské, Toshihiko Yokoyama
Photoelectron spectroscopy has the advantage of providing electric potentials by non-contact measurements based on the kinetic energy shift in component potential. We performed operando hard X-ray photoelectron spectroscopy (HAXPES) measurements with an 8 keV excitation source to measure the shift in electron kinetic energies as a function of the voltages of all the components at the anode and cathode electrodes of a polymer electrolyte fuel cell (PEFC). At the cathode electrode, when we increase the voltage between the cathode and anode from 0...
November 14, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/29131571/nanostructure-of-fully-injectable-hydrazone-thiosuccinimide-interpenetrating-polymer-network-hydrogels-assessed-by-small-angle-neutron-scattering-and-dstorm-single-molecule-fluorescence-microscopy
#20
Trevor Gilbert, Richard J Alsop, Mouhanad Babi, Jose Moran-Mirabal, Maikel C Rheinstadter, Todd Hoare
Herein, we comprehensively investigate the internal morphology of fully injectable IPNs prepared via co-extrusion of functionalized precursor polymer solutions based on thermoresponsive poly(N-isopropylacrylamide) and non-thermoresponsive poly(vinyl pyrrolidone) by reactive mixing using kinetically orthogonal hydrazone and thiosuccinimide cross-linking mechanisms. Small angle neutron scattering (SANS), probing both the full IPN as well as the individual constituent networks of the IPN using index matching, suggests a partially mixed internal structure characterized by PNIPAM-rich domains entrapped in a clustered PVP-rich phase...
November 13, 2017: ACS Applied Materials & Interfaces
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