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https://www.readbyqxmd.com/read/28107552/reflections-on-the-history-of-indoor-air-science-focusing-on-the-last-50-years
#1
Jan Sundell
The scientific articles and Indoor Air conference publications of the indoor air sciences (IAS) during the last 50 years are summarized. In total 7524 presentations, from 79 countries, have been made at Indoor Air conferences held between 1978 (49 presentations) and 2014 (1049 presentations). In the Web of Science 26,992 articles on indoor air research (with the word "indoor" as a search term) have been found (as of 1 Jan 2016) of which 70% were published during the last 10 years. The modern scientific history started in the 1970s with a question: "did indoor air pose a threat to health as did outdoor air?" Soon it was recognized that indoor air is more important, from a health point of view, than outdoor air...
January 20, 2017: Indoor Air
https://www.readbyqxmd.com/read/28107395/prevalence-of-pre-analytical-errors-in-clinical-chemistry-diagnostic-labs-in-sulaimani-city-of-iraqi-kurdistan
#2
Dereen Najat
BACKGROUND: Laboratory testing is roughly divided into three phases: a pre-analytical phase, an analytical phase and a post-analytical phase. Most analytical errors have been attributed to the analytical phase. However, recent studies have shown that up to 70% of analytical errors reflect the pre-analytical phase. The pre-analytical phase comprises all processes from the time a laboratory request is made by a physician until the specimen is analyzed at the lab. Generally, the pre-analytical phase includes patient preparation, specimen transportation, specimen collection and storage...
2017: PloS One
https://www.readbyqxmd.com/read/28107308/acute-right-heart-failure-after-hemorrhagic-shock-and-trauma-pneumonectomy-a-management-approach-a-blinded-randomized-controlled-animal-trial-using-inhaled-nitric-oxide
#3
Andrea L Lubitz, Lars O Sjoholm, Amy Goldberg, Abhijit Pathak, Thomas Santora, Thomas E Sharp, Markus Wallner, Remus M Berretta, Lauren A Poole, Jichuan Wu, Marla R Wolfson
BACKGROUND: Hemorrhagic shock and pneumonectomy causes an acute increase in pulmonary vascular resistance (PVR). The increase in PVR and right ventricular (RV) afterload leads to acute RV failure, thus reducing left ventricular (LV) preload and output. Inhaled nitric oxide (iNO) lowers PVR by relaxing pulmonary arterial smooth muscle without remarkable systemic vascular effects. We hypothesized that with hemorrhagic shock and pneumonectomy, iNO can be used to decrease PVR and mitigate right heart failure...
February 2017: Journal of Trauma and Acute Care Surgery
https://www.readbyqxmd.com/read/28107013/quaternary-n-2-pyridyl-dabco-salts-one-pot-in-situ-formation-from-pyridine-n-oxides-and-reactions-with-nucleophiles-a-mild-and-selective-route-to-substituted-n-2-pyridyl-n-ethylpiperazines
#4
Dmitry I Bugaenko, Marina A Yurovskaya, Alexander V Karchava
The N-(2-pyridyl)-N'-ethylpiperazines are important structural motifs in several medicinally relevant compounds. Known synthetic methods toward these structures are multistep and generally based on the SNAr-chemistry; their applicability is significantly limited to substrates containing electron-withdrawing groups. Here we describe a new methodology for a rapid and modular access to this privileged scaffold. Importantly, the developed protocol proved to be very general and efficient for the substrates containing substituents of different electronic nature...
January 20, 2017: Journal of Organic Chemistry
https://www.readbyqxmd.com/read/28106994/enzymatic-halogenation-and-dehalogenation-reactions-pervasive-and-mechanistically-diverse
#5
Vinayak Agarwal, Zachary D Miles, Jaclyn M Winter, Alessandra S Eustáquio, Abrahim A El Gamal, Bradley S Moore
Naturally produced halogenated compounds are ubiquitous across all domains of life where they perform a multitude of biological functions and adopt a diversity of chemical structures. Accordingly, a diverse collection of enzyme catalysts to install and remove halogens from organic scaffolds has evolved in nature. Accounting for the different chemical properties of the four halogen atoms (fluorine, chlorine, bromine, and iodine) and the diversity and chemical reactivity of their organic substrates, enzymes performing biosynthetic and degradative halogenation chemistry utilize numerous mechanistic strategies involving oxidation, reduction, and substitution...
January 20, 2017: Chemical Reviews
https://www.readbyqxmd.com/read/28106992/discovery-of-n-pyridin-4-yl-1-5-naphthyridin-2-amines-as-potential-tau-pathology-pet-tracers-for-alzheimer-s-disease
#6
Frederik J R Rombouts, José-Ignacio Andrés, Manuela Ariza, José Manuel Alonso, Nigel Austin, Astrid Bottelbergs, Lu Chen, Vladimir Chupakhin, Erna Cleiren, Katleen Fierens, Alberto Fontana, Xavier Langlois, Joseph E Leenaerts, Jonas Mariën, Carolina Martinez Lamenca, Rhys Salter, Mark E Schmidt, Paula Te Riele, Cindy Wintmolders, Andrés A Trabanco, Wei Zhang, Gregor J Macdonald, Diederik Moechars
A mini-HTS on 4000 compounds selected using 2D fragment-based similarity and 3D pharmacophoric and shape similarity to known selective tau aggregate binders identified N-(6-methylpyridin-2-yl)quinolin-2-amine 10 as a novel potent binder to human AD aggregated tau with modest selectivity versus aggregated β-amyloid (Aβ). Initial medicinal chemistry efforts identified key elements for potency and selectivity, as well as suitable positions for radiofluorination, leading to a first generation of fluoroalkyl-substituted quinoline tau binding ligands with sub-optimal physicochemical properties...
January 20, 2017: Journal of Medicinal Chemistry
https://www.readbyqxmd.com/read/28106980/structural-snapshots-of-an-engineered-cystathionine-%C3%AE-lyase-reveal-the-critical-role-of-electrostatic-interactions-in-the-active-site
#7
Wupeng Yan, Everett M Stone, Yan Jessie Zhang
Enzyme therapeutics that can degrade L-methionine (L-Met) are of great interest as numerous malignancies are exquisitely sensitive to L-Met depletion. To exhaust the pool of the methionine in human serum, we previously engineered an L-Met degrading enzyme based on the human cystathionine-γ-lyase scaffold (hCGL-NLV) in order to circumvent immunogenicity and stability issues observed in the preclinical application of bacterial derived methionine-γ-lyases (MGL). To gain further insights into structure/activity relationships governing the chemistry of the hCGL-NLV lead molecule, we undertook a biophysical characterization campaign that captured crystal structures (2...
January 20, 2017: Biochemistry
https://www.readbyqxmd.com/read/28106939/maximizing-output-in-rna-programmed-peptidyl-transfer-reactions
#8
Margherita Di Pisa, Anett Hauser, Oliver Seitz
A chemical reaction that is triggered by specific RNA molecules may provide opportunities for the design of artificial feedback loops. We envision a peptidyl transfer reaction, in which mRNA encoding for antiapoptotic protein would instruct the synthesis of apoptosis-inducing peptides. In this study, we tackled the RNA-programmed synthesis of a 16mer peptide derived from the Bak-BH3 protein which inhibits the antiapoptotic protein Bcl-xL. The reaction involves the transfer of a thioester-linked donor peptide fragment from one PNA conjugate onto an acceptor peptide-PNA conjugate...
January 20, 2017: Chembiochem: a European Journal of Chemical Biology
https://www.readbyqxmd.com/read/28106933/carbatriphyrin-3-1-1-displays-distinct-coordination-approach-of-biii-to-generate-organoborane-and-weak-c-h%C3%A2-b-interactions
#9
Alagar Srinivasan, B Adinarayana, Ajesh P Thomas, Prerna Yadav, Vanga Mukundam
The carbatriphyrin(3.1.1) is the structural isomer of biphenylcorrole and achieved by switching the bonding mode of biphenyl unit from 3,3' to 2,3' which turns the corrole into triphyrin analogue. The presence of m-arene unit in the framework restricts the overall conjugation, thus leads to non-aromatic macrocycle. The protonation experiments afford trifluoroacetate ion complex. The coordination chemistry reveals that the bottom approach of boron(III) ion forms weak C-H...B interactions, however top approach stabilizes the organoborane complex and the product distribution relies on the basicity of the proton scavengers...
January 20, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28106805/synthetic-assembly-of-mannose-moieties-using-polymer-chemistry-and-the-biological-evaluation-of-its-interaction-towards-concanavalin-a
#10
Deepti Diwan, Kohei Shinkai, Toshihiro Tetsuka, Bin Cao, Hidenao Arai, Tetsuo Koyama, Ken Hatano, Koji Matsuoka
Protein-carbohydrate interactions exhibit myriad intracellular recognition events, so understanding and investigating their specific interaction with high selectivity and strength are of crucial importance. In order to examine the effect of multivalent binding on the specificity of protein-carbohydrate interactions, we synthesized mannose glycosides as a novel type of glycosylated monomer and glycopolymers of polyacrylamide derivatives with α-mannose (α-Man) by radical polymerization and monitored their strength of interaction with concanavalin A (Con A) by surface plasmon resonance (SPR) detection...
January 18, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28106796/preparative-scale-resolution-of-enantiomers-enables-accelerated-drug-discovery-and-development
#11
Hanna Leek, Shalini Andersson
The provision of pure enantiomers is of increasing importance not only for the pharmaceutical industry but also for agro-chemistry and biotechnology. In drug discovery and development, the enantiomers of a chiral drug depict unique chemical and pharmacological behaviors in a chiral environment, such as the human body, in which the stereochemistry of the chiral drugs determines their pharmacokinetic, pharmacodynamic and toxicological properties. We present a number of challenging case studies of up-to-kilogram separations of racemic or enriched isomer mixtures using preparative liquid chromatography and super critical fluid chromatography to generate individual enantiomers that have enabled the development of new candidate drugs within AstraZeneca...
January 18, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28106775/colloidal-fouling-of-nanofiltration-membranes-development-of-a-standard-operating-procedure
#12
Md Abdullaha Al Mamun, Subir Bhattacharjee, David Pernitsky, Mohtada Sadrzadeh
Fouling of nanofiltration (NF) membranes is the most significant obstacle to the development of a sustainable and energy-efficient NF process. Colloidal fouling and performance decline in NF processes is complex due to the combination of cake formation and salt concentration polarization effects, which are influenced by the properties of the colloids and the membrane, the operating conditions of the test, and the solution chemistry. Although numerous studies have been conducted to investigate the influence of these parameters on the performance of the NF process, the importance of membrane preconditioning (e...
January 18, 2017: Membranes
https://www.readbyqxmd.com/read/28106754/advances-in-solid-state-transformations-of-coordination-bonds-from-the-ball-mill-to-the-aging-chamber
#13
REVIEW
Cristina Mottillo, Tomislav Friščić
Controlling the formation of coordination bonds is pivotal to the development of a plethora of functional metal-organic materials, ranging from coordination polymers, metal-organic frameworks (MOFs) to metallodrugs. The interest in and commercialization of such materials has created a need for more efficient, environmentally-friendly routes for making coordination bonds. Solid-state coordination chemistry is a versatile greener alternative to conventional synthesis, offering quantitative yields, enhanced stoichiometric and topological selectivity, access to a wider range of precursors, as well as to molecules and materials not readily accessible in solution or solvothermally...
January 17, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28106383/synthesis-chemistry-and-electronic-structures-of-group-9-metallaboranes
#14
Rosmita Borthakur, Sourav Kar, Subrat Kumar Barik, Somnath Bhattacharya, Gargi Kundu, Babu Varghese, Sundargopal Ghosh
Dimetallaoctaborane(12) of Ru, Co, and Rh have been well-characterized by a range of spectroscopic techniques and X-ray diffraction studies. Thus, reinvestigation of the Ir-system became of interest. As a result, a slight modification in the reaction conditions enabled us to isolate the missing Ir analogue of octaborane(12), [(Cp*Ir)2B6H10], 1. Compound 1 adapts a geometry similar to that of its parent octaborane(12) and Ru, Co, and Rh analogues. In [M2B6H10+x](M = Ru, x = 2; M = Co and Rh, x = 0), there exist two M-H-B protons...
January 20, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28106367/alignment-of-carbon-nanotubes-in-carbon-nanotube-fibers-through-nanoparticles-a-route-for-controlling-mechanical-and-electrical-properties
#15
Muhammad Mohsin Hossain, Md Akherul Islam, Hossain Shima, Mudassir Hasan, Moonyong Lee
This is the first study that describes how semiconducting ZnO can act as an alignment agent in carbon nanotubes (CNTs) fibers. Due to the alignment of CNTs through the ZnO nanoparticles linking groups, the CNTs inside the fibers were equally distributed by the attraction of bonding forces into sheet-like bunches, such that any applied mechanical breaking load was equally distributed to each CNT inside the fiber, making them mechanically robust against breaking loads. Although semiconductive ZnO nanoparticles were used here, the electrical conductivity of the aligned CNT fiber was comparable to bare CNT fibers, suggesting that the total electron movement through the CNTs inside the aligned CNT fiber is not disrupted by the insulating behavior of ZnO nanoparticles...
January 20, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28106350/thermally-adjustable-dynamic-disulfide-linkages-mediated-by-highly-air-stable-2-2-6-6-tetramethylpiperidine-1-sulfanyl-temps-radicals
#16
Akira Takahashi, Raita Goseki, Hideyuki Otsuka
Intrinsically exchangeable dynamic covalent bonds that can be triggered by readily usable stimuli offer easy incorporation of their dynamic properties in various molecular systems, but the library of such bonds is still being developed. Herein, we report the dynamic covalent chemistry of 2,2,6,6-tetramethylpiperidine-1-sulfanyl (TEMPS) dimers derived from thermally reversible homolytic dissociation of disulfide linkages. High air stability of TEMPS was observed even at 100 °C, affording facile employment of thermal dissociation-association equilibria and adjustable bond exchange properties under atmospheric conditions...
January 20, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28106305/diversity-oriented-peptide-stapling-a-third-generation-cuaac-stapling-and-functionalisation-strategy
#17
Thu Tran Phuong, Christian Ørnbøl Larsen, Tobias Røndbjerg, Martina De Foresta, Micha Ben Achim Kunze, Ales Marek, Jacob Hartvig Løper, Lotte-Emilie Boyhus, Astrid Knuhtsen, Kresten Lindorff-Larsen, Daniel Sejer Pedersen
The introduction of macrocyclic constraints in peptides (peptide stapling) is an important tool within peptide medicinal chemistry for stabilising and pre-organising peptides in a desired conformation. In recent years, the copper-catalysed azide-alkyne cycloaddition (CuAAC) has emerged as a powerful method for peptide stapling. However, to date CuAAC stapling has not provided a simple method for obtaining peptides that are easily diversified further. In the present study, we report a new diversity-oriented peptide stapling (DOPS) methodology based on CuAAC chemistry...
January 20, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28106210/multi-step-continuous-flow-synthesis
#18
Joshua Britton, Colin L Raston
Organic chemistry is continually evolving to improve the syntheses of value added and bioactive compounds. Through this progression, a concomitant advancement in laboratory technology has occurred. Many researchers now choose to mediate transformations in continuous-flow systems given the many benefits over round bottom flasks. Furthermore, reaction scale up is often less problematic as this is addressed at the inception of the science. Although single-step transformations in continuous-flow systems are common, multi-step transformations are more valuable...
January 20, 2017: Chemical Society Reviews
https://www.readbyqxmd.com/read/28106196/solubility-origin-at-the-nanoscale-enthalpic-and-entropic-contributions-in-polar-and-nonpolar-environments
#19
Eudes Fileti, Vitaly V Chaban
Nanostructures are known to be poorly soluble, irrespective of their elemental composition, shape, electronic structure, dipole moment, hydrophobicity/hydrophilicity and the employed solvent. The methods of colloid chemistry allow for preparing suspensions - metastable systems, the stabilities of which differ greatly from one another - but not real solutions. A systematic investigation of the solubility origin at the nanoscale is hereby reported in terms of its fundamental constituents: enthalpy and entropy...
January 20, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28106193/light-driven-reversible-surface-functionalization-with-anthracenes-visible-light-writing-and-mild-uv-erasing
#20
Tanja K Claus, Siham Telitel, Alexander Welle, Martin Bastmeyer, Andrew P Vogt, Guillaume Delaittre, Christopher Barner-Kowollik
We introduce a methodology to reversibly pattern planar surfaces via the light-induced dimerization of anthracenes, particularly involving a 9-triazolylanthracene motif. Specifically, we demonstrate that the visible light-induced forward reaction can be employed to pattern small molecule species as well as polymers in a spatially resolved fashion. Under UV irradiation, the generated patterns can be erased to regenerate reactive areas, which are then available for a new functionalization step. The dynamic change in surface chemistry is evidenced by ToF-SIMS...
January 20, 2017: Chemical Communications: Chem Comm
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