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https://www.readbyqxmd.com/read/28938624/addition-of-2-ethylamino-acetonitrile-group-to-nitroxoline-results-in-significantly-improved-anti-tumor-activity-in-vitro-and-in-vivo
#1
Ana Mitrović, Izidor Sosič, Špela Kos, Urša Lampreht Tratar, Barbara Breznik, Simona Kranjc, Bojana Mirković, Stanislav Gobec, Tamara Lah, Gregor Serša, Janko Kos
Lysosomal cysteine peptidase cathepsin B, involved in multiple processes associated with tumor progression, is validated as a target for anti-cancer therapy. Nitroxoline, a known antimicrobial agent, is a potent and selective inhibitor of cathepsin B, hence reducing tumor progression in vitro and in vivo. In order to further improve its anti-cancer properties we developed a number of derivatives using structure-based chemical synthesis. Of these, the 7-aminomethylated derivative (compound 17) exhibited significantly improved kinetic properties over nitroxoline, inhibiting cathepsin B endopeptidase activity selectively...
August 29, 2017: Oncotarget
https://www.readbyqxmd.com/read/28938515/regulation-of-hepatic-hydroxy-methyl-glutarate-coa-reductase-for-controlling-hypercholesterolemia-in-rats
#2
Abeer A Khamis, Afrah F Salama, Marwa E Kenawy, Tarek M Mohamed
Hypercholesterolemia is a major risk factor upon developing cardiovascular diseases. This study is aiming to investigate the inhibition role of quercetin on hydroxy methyl glutarate - CoA reductase activity and its gene for attenuating hypercholesterolemia. The kinetic characteristics of HMG-CoA reductase activity were evaluated on extracellular rat liver microsomes. For studying the effect of quercetin by inducing hypercholesterolemia rats by Tyloxapol (i.v.). In addition, rats were treated with different doses of quercetin according to the inhibition constant of this inhibitor...
September 18, 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/28938478/roux-en-y-gastric-bypass-surgery-has-unique-effects-on-postprandial-fgf21-but-not-fgf19-secretion
#3
Lydia-Ann L S Harris, Gordon I Smith, Bettina Mittendorfer, J Christopher Eagon, Adewole L Okunade, Bruce W Patterson, Samuel Klein
Context: Fibroblast growth factors (FGF) 19 and FGF21 are secreted by the intestine and liver in response to macronutrient intake. Intestinal resection and reconstruction via bariatric surgery may alter their regulation. Objective: We tested the hypothesis that weight loss induced by Roux-en-Y gastric bypass (RYGB) surgery, but not matched weight loss induced by laparoscopic adjustable gastric banding (LAGB), increases postprandial plasma FGF19 and FGF21 concentrations...
August 17, 2017: Journal of Clinical Endocrinology and Metabolism
https://www.readbyqxmd.com/read/28938466/optogenetic-analysis-of-depolarization-dependent-glucagon-like-peptide-1-release
#4
Catalin Chimerel, Cristian Riccio, Keir Murison, Fiona M Gribble, Frank Reimann
Incretin hormones play an important role in the regulation of food intake and glucose homeostasis. Glucagon-like peptide-1 (GLP-1) secreting cells have been demonstrated to be electrically excitable and to fire action potentials (APs) with increased frequency in response to nutrient exposure. However, nutrients can also be metabolised or activate G-protein-coupled receptors, thus potentially stimulate GLP-1 secretion independent of their effects on the plasma membrane potential. Here we used channelrhodopsins to manipulate the membrane potential of GLUTag cells, a well established model of GLP-1 secreting enteroendocrine L-cells...
July 28, 2017: Endocrinology
https://www.readbyqxmd.com/read/28938418/androgens-support-male-acrobatic-courtship-behavior-by-enhancing-muscle-speed-and-easing-the-severity-of-its-trade-off-with-force
#5
Matthew J Fuxjager, Meredith C Miles, Franz Goller, John Petersen, Julia Yancey
Steroid hormone action in the brain regulates many animals' elaborate social displays used for courtship and competition, but it is increasingly recognized that the periphery may also be a site for potent steroidal modulation of complex behavior. However, the mechanisms of such "bottom up" regulation of behavioral outflow are largely unclear. To study this problem, we examine how androgenic sex hormones act through the skeletal muscular system to mediate elaborate courtship acrobatics in a tropical bird called the golden-collared manakin...
August 29, 2017: Endocrinology
https://www.readbyqxmd.com/read/28938305/a-useful-device-to-measure-kinetics-of-platelet-contraction
#6
Mitchell J George, Kevin R Aroom, Max A Skibber, Tushar Sharma, Charles E Wade, Charles S Cox, Brijesh S Gill
Platelet contraction provides a minimally invasive source for physiologic information. In this article, we describe a device that directly measures the kinetics of platelet contraction. Whole blood is injected between acrylic plates and an adherent clot forms. The bottom plate is fixed, and the top plate is attached to a wire cantilever. Platelet contraction drives deflection of the wire cantilever which is captured by a camera. Force generated by the clot with time is derived using beam equations. Force derivations were verified using a microelectromechanical (MEMS) force sensor...
September 21, 2017: ASAIO Journal: a Peer-reviewed Journal of the American Society for Artificial Internal Organs
https://www.readbyqxmd.com/read/28938216/efficient-removal-of-priority-hazardous-priority-and-emerging-pollutants-with-prunus-armeniaca-functionalized-biochar-from-aqueous-wastes-experimental-optimization-and-modeling
#7
Maja Turk Sekulić, Sabolč Pap, Zoran Stojanović, Nikola Bošković, Jelena Radonić, Tatjana Šolević Knudsen
This paper investigates the ability of the phosphoric acid functionalized Prunus armeniaca stones biochar (AsPhA) prepared by thermochemical activation to remove lead (Pb(2+)), cadmium (Cd(2+)), nickel (Ni(2+)), naproxen and chlorophenols from aqueous wastes. The engineered biochar was characterized using the Scanning Electron Microscopy, Energy-dispersive X-ray Spectroscopy, Fourier Transform Infrared Spectroscopy and Brunauer, Emmett and Teller technique. The batch studies were performed by varying the initial pH of the solution (2-9), adsorbent dosage (0...
September 19, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28938196/sorption-of-uranium-vi-onto-hydrous-ferric-oxide-modified-zeolite-assessment-of-the-effect-of-ph-contact-time-temperature-selected-cations-and-anions-on-sorbent-interactions
#8
Pfano Mathews Nekhunguni, Nikita Tawanda Tavengwa, Hlanganani Tutu
Zeolites are commonly used as adsorbents for metal removal in most applications e.g. in wastewater. However, the ubiquity of iron in such systems may, in the long-term, distort the true interactions and mechanisms of contaminant removal as a result of modification of the zeolite surface. In this study, this potential phenomenon was assessed for the removal of uranium(VI) from aqueous solution by hydrous ferric oxide-modified zeolite (HFOMZ). This was prepared by precipitating iron hydroxide (the common precipitate of iron in aqueous systems) onto zeolite...
September 19, 2017: Journal of Environmental Management
https://www.readbyqxmd.com/read/28938165/a-novel-dopa-albumin-based-tissue-adhesive-for-internal-medical-applications
#9
Wenzhen Zhu, Yvonne Peck, Jabed Iqbal, Dong-An Wang
To date, existing tissue adhesives have various weak points in gluing kinetics and stability - particularly, in biocompatibility, which make most of them remain suboptimal for internal conditions. Herein, a novel mussel-inspired "BCD" tissue glue made of bovine serum albumin (BSA), citrate acid (CA) and dopamine was developed aiming at internal medical applications. BSA was employed as a natural and biocompatible macromolecular backbone; CA was introduced as a dual-functional intermediate to increase reactive carboxyl sites for engraftment of dopamine onto BSA backbone and also block the competing reactive amines from the proteinic backbone...
September 14, 2017: Biomaterials
https://www.readbyqxmd.com/read/28938156/removal-of-intra-and-extracellular-microcystin-by-submerged-ultrafiltration-uf-membrane-combined-with-coagulation-flocculation-and-powdered-activated-carbon-pac-adsorption
#10
Ayşe Büşra Şengül, Gamze Ersan, Neşe Tüfekçi
In this study, we investigated the performance of conventional (coagulation/flocculation→powdered activated carbon [PAC] adsorption) and advanced treatment (coagulation/flocculation→PAC adsorption→submerged ultrafiltration [UF] membrane) processes separately and sequentially for the removal of total (intra- and extracellular) microcystin. Results of the conventional treatment process demonstrated that coagulation/flocculation alone was not effective (up to 70%) for the removal of total microcystin, while the uptake of total microcystin was achieved up to 84% by PAC adsorption (PAC dose of 20mg/L)...
September 13, 2017: Journal of Hazardous Materials
https://www.readbyqxmd.com/read/28938140/encapsulating-fe3o4-into-calcium-alginate-coated-chitosan-hydrochloride-hydrogel-beads-for-removal-of-cu-ii-and-u-vi-from-aqueous-solutions
#11
Xiaofeng Yi, Jiarui He, Yingyuan Guo, Zhenhua Han, Meixia Yang, Jiali Jin, Junjie Gu, Minrui Ou, Xiaoping Xu
The aim of this work was to study the removal of Cu (II) and U (VI) ions from aqueous solutions by encapsulating magnetic Fe3O4 nanoparticles into calcium alginate coated chitosan hydrochloride (CCM) hydrogel beads. ATR-FTIR and XRD analysis data indicated that the CCM composites were successfully prepared. SEM images and EDX spectra showed that Cu(2+) and UO2(2+) ions were adhered onto sorbents. Adsorption properties for removal of both copper and uranium ions under various experimental conditions were investigated...
September 19, 2017: Ecotoxicology and Environmental Safety
https://www.readbyqxmd.com/read/28938116/a-unifying-theory-of-branching-morphogenesis
#12
Edouard Hannezo, Colinda L G J Scheele, Mohammad Moad, Nicholas Drogo, Rakesh Heer, Rosemary V Sampogna, Jacco van Rheenen, Benjamin D Simons
The morphogenesis of branched organs remains a subject of abiding interest. Although much is known about the underlying signaling pathways, it remains unclear how macroscopic features of branched organs, including their size, network topology, and spatial patterning, are encoded. Here, we show that, in mouse mammary gland, kidney, and human prostate, these features can be explained quantitatively within a single unifying framework of branching and annihilating random walks. Based on quantitative analyses of large-scale organ reconstructions and proliferation kinetics measurements, we propose that morphogenesis follows from the proliferative activity of equipotent tips that stochastically branch and randomly explore their environment but compete neutrally for space, becoming proliferatively inactive when in proximity with neighboring ducts...
September 21, 2017: Cell
https://www.readbyqxmd.com/read/28938017/a-highly-conserved-amino-acid-in-vp1-regulates-maturation-of-enterovirus-71
#13
Yong-Xin Zhang, Yu-Ming Huang, Quan-Jie Li, Xiao-Yu Li, Yong-Dong Zhou, Fei Guo, Jin-Ming Zhou, Shan Cen
Enterovirus 71 (EV71) is the major causative agent of hand, foot and mouth disease (HFMD) in children, causing severe clinical outcomes and even death. Here, we report an important role of the highly conserved alanine residue at position 107 in the capsid protein VP1 (VP1A107) in the efficient replication of EV71. Substitutional mutations of VP1A107 significantly diminish viral growth kinetics without significant effect on viral entry, expression of viral genes and viral production. The results of mechanistic studies reveal that VP1A107 regulates the efficient cleavage of the VP0 precursor during EV71 assembly, which is required, in the next round of infection, for the transformation of the mature virion (160S) into an intermediate or A-particle (135S), a key step of virus uncoating...
September 22, 2017: PLoS Pathogens
https://www.readbyqxmd.com/read/28937947/wastewater-treatment-by-means-of-thermophilic-aerobic-membrane-reactors-respirometric-tests-and-numerical-models-for-determination-of-stoichiometric-kinetic-parameters
#14
Maria Cristina Collivignarelli, Giorgio Bertanza, Alessandro Abbà, Vincenzo Torretta, Ioannis Anastasios Katsoyiannis
The present work considers the pollution abatement of wastewaters, the efficiency of which is depending on stringent verification of the performance of wastewater treatment plants. This is very important especially given that eExisting wastewater/aqueous waste treatment plants often need to be upgraded in order to improve their performance. The satisfactory operation of biological treatment plants requires appropriate monitoring, and respirometric techniques are needed to determine the kinetic parameters that regulate biological processes...
September 22, 2017: Environmental Technology
https://www.readbyqxmd.com/read/28937920/biodegradation-of-imidacloprid-in-liquid-media-by-an-isolated-wastewater-fungus-aspergillus-terreus-yesm3
#15
Youssef M M Mohammed, Mohammed E I Badawy
In the present study, a new fungal strain capable of imidacloprid degradation was isolated from agricultural wastewater drain. The fungal strain of YESM3 was identified as Aspergillus terreus based on ITS1-5.8S rDNA-ITS2 gene sequence by PCR amplification of a 500 bp sequence. Screening of A. terreus YESM3 to the insecticide imidacloprid tolerance was achieved by growing fungus in Czapek Dox agar for 6 days at 28°C. High values (1.13 and 0.94 cm cm(-1)) of tolerance index (TI) were recorded at 25 and 50 mg L(-1) of imidacloprid, respectively in the presence and absence of sucrose...
September 22, 2017: Journal of Environmental Science and Health. Part. B, Pesticides, Food Contaminants, and Agricultural Wastes
https://www.readbyqxmd.com/read/28937775/operando-phonon-studies-of-the-protonation-mechanism-in-highly-active-hydrogen-evolution-reaction-pentlandite-catalysts
#16
Ioannis Zegkinoglou, Ali Zendegani, Ilya Sinev, Sebastian Kunze, Hemma Mistry, Hyo Sang Jeon, Jiyong Zhao, Michael Y Hu, E Ercan Alp, Stefan Piontek, Mathias Smialkowski, Ulf-Peter Apfel, Fritz Körmann, Jorg Neugebauer, Tilmann Hickel, Beatriz Roldan Cuenya
Synthetic pentlandite (Fe4.5Ni4.5S8) is a promising electrocatalyst for hydrogen evolution, demonstrating high current densities, low overpotential and remarkable stability in bulk form. The depletion of sulfur from the surface of this catalyst during the electrochemical reaction has been proposed to be beneficial for its catalytic performance, but the role of sulfur vacancies and the mechanism determining the reaction kinetics are still unknown. We have performed electrochemical operando studies of the vibrational dynamics of pentlandite under hydrogen evolution reaction conditions using 57Fe nuclear resonant inelastic X-ray scattering...
September 22, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28937756/direct-comparison-of-c-h-bond-amination-efficacy-through-manipulation-of-nitrogen-valence-centered-redox-imido-versus-iminyl
#17
Matthew J T Wilding, Diana A Iovan, Alexandra T Wrobel, James T Lukens, Samantha N MacMillan, Kyle M Lancaster, Theodore A Betley
Reduction of previously reported iminyl radical (ArL)FeCl(•N(C6H4-p-tBu)) (2) with potassium graphite furnished the corresponding high-spin (S = 5/2) imido (ArL)Fe(N(C6H4-p-tBu)) (3) (ArL = 5-mesityl-1,9-(2,4,6-Ph3C6H2)dipyrrin). Oxidation of the three-coordinate imido (ArL)Fe(NAd) (5) with chlorotriphenylmethane afforded (ArL)FeCl(•NAd) (6) with concomitant expulsion of Ph3C(C6H5)CPh2. The respective alkyl/aryl imido/iminyl pairs (3, 2; 5, 6) have been characterized by EPR, zero-field 57Fe Mössbauer, magnetometry, single crystal X-ray diffraction, XAS, and EXAFS for 6...
September 22, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28937744/methane-c-h-activation-via-3d-metal-methoxide-complexes-with-potentially-redox-noninnocent-pincer-ligands-a-density-functional-theory-study
#18
Ahmad Najafian, Thomas R Cundari
This paper reports a density functional theory study of 3d transition-metal methoxide complexes with potentially redox-noninnocent pincer supporting ligands for methane C-H bond activation to form methanol (LnM-OMe + CH4 → LnM-Me + CH3OH). The three types of tridentate pincer ligands [terpyridine (NNN), bis(2-pyridyl)phenyl-C,N,N' (NCN), and 2,6-bis(2-phenyl)pyridine-N,C,C' (CNC)] and different first-row transition metals (M = Ti, V, Cr, Mn, Fe, Co, Ni, and Cu) are used to elucidate the reaction mechanism as well as the effect of the metal identity on the thermodynamics and kinetics of a methane activation reaction...
September 22, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28937698/evolution-of-mechanics-in-%C3%AE-helical-peptide-conjugated-linear-and-star-block-peg
#19
S C O'Neill, Z H Bhuiyan, R S Tu
We have designed a peptide conjugated poly-ethylene glycol (PEG) bioconjugate system that allows us to examine the intra- and inter-molecular dynamics of gelation. We measure the kinetics of gelation for end-functionalized linear- and star-architectures, and we correlate the gelation behavior with the molecular structure and self-association. The 23-amino acid peptide sequence is known to form a coiled-coil structure as a function of the solution's electrolyte concentration, and the two topologies of the PEG are peptide end-functionalized to examine formation of supramolecular assemblies...
September 22, 2017: Soft Matter
https://www.readbyqxmd.com/read/28937668/complete-protein-protein-association-kinetics-in-atomic-detail-revealed-by-molecular-dynamics-simulations-and-markov-modelling
#20
Nuria Plattner, Stefan Doerr, Gianni De Fabritiis, Frank Noé
Protein-protein association is fundamental to many life processes. However, a microscopic model describing the structures and kinetics during association and dissociation is lacking on account of the long lifetimes of associated states, which have prevented efficient sampling by direct molecular dynamics (MD) simulations. Here we demonstrate protein-protein association and dissociation in atomistic resolution for the ribonuclease barnase and its inhibitor barstar by combining adaptive high-throughput MD simulations and hidden Markov modelling...
October 2017: Nature Chemistry
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