keyword
MENU ▼
Read by QxMD icon Read
search

Chelation

keyword
https://www.readbyqxmd.com/read/28723189/ionophore-based-titrimetric-detection-of-alkali-metal-ions-in-serum
#1
Jingying Zhai, Xiaojiang Xie, Thomas Cherubini, Eric Bakker
While the titrimetric assay is one of the most precise analytical techniques available, only a limited list of complexometric chelators is available, as many otherwise promising reagents are not water-soluble. Recent work demonstrated successful titrimetry with ion-exchanging polymeric nanospheres containing hydrophobic complexing agents, so-called ionophores, opening an exciting avenue in this field. However, this method was limited to ionophores of very high affinity to the analyte and exhibited a relatively limited titration capacity...
April 28, 2017: ACS Sensors
https://www.readbyqxmd.com/read/28723165/kinetic-discrimination-of-metal-ions-using-dna-for-highly-sensitive-and-selective-cr-3-detection
#2
Wang Li, Zijie Zhang, Wenhu Zhou, Juewen Liu
Most metal sensors are designed for a strong binding affinity toward target metal ions, and the underlying principle relies on binding thermodynamics. The kinetic aspect of binding, however, was rarely explored for sensing. In this work, the binding kinetics of 19 common or toxic metal ions are compared based on a fluorescence quenching assay using DNA oligonucleotides as ligands. Among these metals, Cr(3+) shows uniquely slow fluorescence quenching kinetics, and the quenched fluorescence cannot be recovered by EDTA or sulfide...
May 26, 2017: ACS Sensors
https://www.readbyqxmd.com/read/28723098/a-new-area-in-main-group-chemistry-zerovalent-monoatomic-silicon-compounds-and-their-analogues
#3
Shenglai Yao, Yun Xiong, Matthias Driess
Monoatomic zerovalent main-group element complexes emerged very recently and attracted increasing attention of both theoretical and experimental chemists. In particular, zerovalent silicon complexes and their congeners (metallylones) stabilized by neutral Lewis donors are of significant importance not only because of their intriguing electronic structure but also because they can serve as useful building blocks for novel chemical species. Featuring four valence electrons as two lone pairs at the central atoms, such complexes may form donor-acceptor adducts with Lewis acids...
July 19, 2017: Accounts of Chemical Research
https://www.readbyqxmd.com/read/28723082/mixed-valency-in-a-3d-semiconducting-iron-fluoranilate-coordination-polymer
#4
Ryuichi Murase, Brendan F Abrahams, Deanna M D'Alessandro, Casey G Davies, Timothy A Hudson, Guy N L Jameson, Boujemaa Moubaraki, Keith S Murray, Richard Robson, Ashley L Sutton
A pair of coordination polymers of composition (NBu4)2[M2(fan)3] (fan = fluoranilate; M = Fe and Zn) were synthesized and structurally characterized. In each case the compound consists of a pair of interpenetrating three-dimensional, (10,3)-a networks in which metal centers are linked by chelating/bridging fluoranilate ligands. Tetrabutylammonium cations are located in the spaces between the two networks. Despite the structural similarity, significant differences exist between (NBu4)2[Fe2(fan)3] and (NBu4)2[Zn2(fan)3] with respect to the oxidation states of the metal centers and ligands...
July 19, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28721605/how-to-provide-gadolinium-free-pet-mr-cancer-staging-of-children-and-young-adults-in-less-than-1%C3%A2-h-the-stanford-approach
#5
Anne M Muehe, Ashok J Theruvath, Lillian Lai, Maryam Aghighi, Andrew Quon, Samantha J Holdsworth, Jia Wang, Sandra Luna-Fineman, Neyssa Marina, Ranjana Advani, Jarrett Rosenberg, Heike E Daldrup-Link
PURPOSE: To provide clinically useful gadolinium-free whole-body cancer staging of children and young adults with integrated positron emission tomography/magnetic resonance (PET/MR) imaging in less than 1 h. PROCEDURES: In this prospective clinical trial, 20 children and young adults (11-30 years old, 6 male, 14 female) with solid tumors underwent 2-deoxy-2-[(18)F]fluoro-D-glucose ([(18)F]FDG) PET/MR on a 3T PET/MR scanner after intravenous injection of ferumoxytol (5 mg Fe/kg) and [(18)F]FDG (2-3 MBq/kg)...
July 18, 2017: Molecular Imaging and Biology: MIB: the Official Publication of the Academy of Molecular Imaging
https://www.readbyqxmd.com/read/28720395/acetazolamide-and-n-acetylcysteine-in-the-treatment-of-chronic-mountain-sickness-monge-s-disease
#6
Shailendra Sharma, Jane Gralla, Joyce Gonzalez Ordonez, Maria-Elena Hurtado, Erik R Swenson, Robert B Schoene, Jackeline Pando Kelly, David Callacondo, Christopher Rivard, Carlos Roncal-Jimenez, Jeffrey Sirota, Richard Fuquay, Brian P Jackson, Kai E Swenson, Richard J Johnson, Abdias Hurtado, Elizabeth Escudero
Patients suffering from chronic mountain sickness (CMS) have excessive erythrocytosis. Low -level cobalt toxicity as a likely contributor has been demonstrated in some subjects. We performed a randomized, placebo controlled clinical trial in Cerro de Pasco, Peru (4,380 m), where 84 participants with a hematocrit (HCT) ≥65% and CMS score>6, were assigned to four treatment groups of placebo, acetazolamide (ACZ, which stimulates respiration), N-acetylcysteine (NAC, an antioxidant that chelates cobalt) and combination of ACZ and NAC for 6 weeks...
July 15, 2017: Respiratory Physiology & Neurobiology
https://www.readbyqxmd.com/read/28719386/is-there-a-standard-of-care-for-transfusion-therapy-in-thalassemia
#7
Massimo Franchini, Gian L Forni, Giancarlo M Liumbruno
PURPOSE OF REVIEW: Thalassemia is the most common form of inherited anemia, characterized by variable clinical phenotypes. The purpose of this review is to summarize the transfusion support in thalassemia patients and the management of transfusion-related iron overload. RECENT FINDINGS: The most recent evidence on transfusion strategy and iron chelation therapy in thalassemia arising from clinical trials as well as from recommendation guidelines are critically discussed...
July 14, 2017: Current Opinion in Hematology
https://www.readbyqxmd.com/read/28719149/cadmium-induced-toxicity-is-rescued-by-curcumin-a-review
#8
REVIEW
Mohammad Mohajeri, Mehdi Rezaee, Amirhossein Sahebkar
Cadmium (Cd) is one of the most common environmental and occupational heavy metals with extended distribution. Exposure to Cd may be associated with several deleterious consequences on the liver, bones, kidneys, lungs, testes, brain, immunological, and cardiovascular systems. Overproduction of reactive oxygen species (ROS) as the main mechanism behind its toxicity causes oxidative stress and subsequent damages to lipids, proteins, and DNA. Therefore, antioxidants along with chelating agents have shown promising outcomes against Cd-induced toxicity...
July 18, 2017: BioFactors
https://www.readbyqxmd.com/read/28718476/strong-ferromagnetic-exchange-coupling-in-a-ni-cluster-mediated-through-an-air-stable-tetrazine-based-radical-anion
#9
Maykon A Lemes, Gabriel Brunet, Amélie Pialat, Liviu Ungur, Ilia Korobkov, Muralee Murugesu
A planar tetradentate 3,6-bis(2-pyrimidyl)-1,2,4,5-tetrazine (BpymTz) templating chelate affords the formation of an unprecedented BpymTz˙(-) radical anion bridged {Ni} complex. Detailed magnetic measurements performed on the isolated air stable [Ni(BpymTz˙(-))Cl6(DMF)8]Cl·0.5(H2O) compound reveal strong ferromagnetic Ni(II)-BpymTz˙(-) interactions with a coupling constant of J = 98.84 cm(-1).
July 18, 2017: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/28715731/metabolomics-analysis-reveals-that-benzo-a-pyrene-a-component-of-pm2-5-promotes-pulmonary-injury-by-modifying-lipid-metabolism-in-a-phospholipase-a2-dependent-manner-in-vivo-and-in-vitro
#10
Song-Yang Zhang, Danqing Shao, Huiying Liu, Juan Feng, Baihuan Feng, Xiaoming Song, Qian Zhao, Ming Chu, Changtao Jiang, Wei Huang, Xian Wang
Particulate matter with an aerodynamic diameter less than 2.5μM (PM2.5) is one of the major environmental pollutants in China. In this study, we carried out a metabolomics profile study on PM2.5-induced inflammation. PM2.5 from Beijing, China, was collected and given to rats through intra-tracheal instillation in vivo. Acute pulmonary injury were observed by pulmonary function assessment and H.E. staining. The lipid metabolic profile was also altered with increased phospholipid and sphingolipid metabolites in broncho-alveolar lavage fluid (BALF) after PM2...
July 4, 2017: Redox Biology
https://www.readbyqxmd.com/read/28715615/rational-design-chemical-development-and-stability-assessment-of-a-new-macrocyclic-four-hydroxamates-bearing-bifunctional-chelating-agent-for-89zr
#11
Uwe Seibold, Björn Wängler, Carmen Wängler
89Zr is a positron-emitting radionuclide being of high interest for medical imaging applications with Positron Emission Tomography. For the introduction of this radiometal into biologically active targeting vectors, the chelating agent desferrioxamine B (DFO) is commonly applied which is however known to form 89Zr-complexes of limited in vivo stability. We herein describe the rational design and chemical development a new, macrocyclic, four hydroxamates-bearing chelating agent (CTH36) for the stable complexation of Zr4+...
July 17, 2017: ChemMedChem
https://www.readbyqxmd.com/read/28715604/antioxidant-activities-and-phenolic-compounds-of-several-tissues-of-pawpaw-asimina-triloba-l-dunal-grown-in-korea
#12
Jin-Sik Nam, Hye-Lim Jang, Young Ha Rhee
Pawpaw (Asimina triloba [L.] Dunal) possesses antioxidant compounds and strong inhibitors of cancer cells, and is widely cultivated in North America, Canada, and Korea. We analyzed the total phenolic and total flavonoid contents (TPC and TFC, respectively) of pawpaw plants grown in Korea and the antioxidant activities of their roots, twigs, leaves, and fruit with respect to 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging activity, 2,2'-azino-bis diammonium salt (ABTS) radical scavenging activity, ferrous (Fe(2+) ) chelating ability, and nitrite scavenging activity...
July 17, 2017: Journal of Food Science
https://www.readbyqxmd.com/read/28715216/long-term-effect-of-a-leonardite-iron-humate-improving-fe-nutrition-as-revealed-in-silico-in-vivo-and-in-field-experiments
#13
Maria Teresa Cieschi, Marcos Caballero-Molada, Nieves Menéndez, Miguel Ángel Naranjo, Juan J Lucena
Novel, cheap and ecofriendly fertilizers that solve the usual iron deficiency problem in calcareous soil are needed. The aim of this work is to study the long term effect of an iron leonardite fertilizer on citrus nutrition taking into account a properly characterization, kinetic response with a ligand competition experiment, efficiency assessment using Saccharomyces cerevisiae strain and finally, in field conditions with citrus as test plants. Its efficiency was compared with the synthetic iron chelate FeEDDHA...
July 17, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28715214/exploiting-carbonyl-groups-to-control-intermolecular-rhodium-catalyzed-alkene-and-alkyne-hydroacylation
#14
Thomas J Coxon, Maitane Fernández, James Barwick-Silk, Alasdair I McKay, Louisa E Britton, Andrew S Weller, Michael C Willis
Readily available β-carbonyl-substituted aldehydes are shown to be exceptional substrates for Rh-catalyzed intermolecular alkene and alkyne hydroacylation reactions. By using cationic rhodium catalysts incorporating bisphosphine ligands, efficient and selective reactions are achieved for β-amido, β-ester, and β-keto aldehyde substrates, providing a range of synthetically useful 1,3-dicarbonyl products in excellent yields. A correspondingly broad selection of alkenes and alkynes can be employed. For alkyne substrates, the use of a catalyst incorporating the Ampaphos ligand triggers a regioselectivity switch, allowing both linear and branched isomers to be prepared with high selectivity in an efficient manner...
July 17, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28715006/substitution-reactions-of-iron-ii-carbamoyl-thioether-complexes-related-to-mono-iron-hydrogenase
#15
Zhu-Lin Xie, Gummadi Durgaprasad, Azim K Ali, Michael J Rose
A C,N,S pincer complex has been synthesized for structural modeling of the organometallic active site of mono-[Fe] hydrogenase (HMD). The C,N,S chelate allows for systematic investigation of the substitution reactions of CO and other exogenous X/L-type ligands, as well as examination of the exact roles of the Fe-carbamoyl and {Fe(CO)2}(2+) units in stabilizing the low-spin Fe(ii) center. Reaction of the 'apo-ligand' 6-(2-(methylthio)phenyl)pyridin-2-amine ((H2N)N(py)S(Me)) with [Fe(CO)4(Br)2] affords the organometallic complex [((O[double bond, length as m-dash])C(NH)N(py)S(Me))Fe(CO)2(Br)] (1)...
July 17, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/28714505/the-antiproliferative-activity-of-di-2-pyridylketone-dithiocarbamate-is-partly-attributed-to-catalase-inhibition-detailing-the-interaction-by-spectroscopic-methods
#16
Cuiping Li, Youxun Liu, Yun Fu, Tengfei Huang, Lixia Kang, Changzheng Li
The bioactivity of drugs is attributed to their interaction with biological molecules, embodied in either their direct or indirect influence on enzyme activity and conformation. Di-2-pyridylketone hydrazine dithiocarbamate (DpdtC) exhibits significant antitumor activity in our preliminary study. We speculated that its activity may partly stem from enzyme inhibition due to strong metal chelating ability. To this end, we assessed its effect on catalase from erythrocytes and found evidence of inhibition, which was further confirmed by ROS determination in vivo...
July 17, 2017: Molecular BioSystems
https://www.readbyqxmd.com/read/28714395/five-decades-of-cuprizone-an-updated-model-to-replicate-demyelinating-diseases
#17
Jose M Vega-Riquer, Gerardo Mendez-Victoriano, Raul A Morales-Luckie, Oscar Gonzalez-Perez
Multiple sclerosis, Guillain-Barré syndrome, peripheral nerve polyneuropathy and others comprise a group of demyelinating diseases characterized by progressive (and eventually irreversible) loss of oligodendrocytes and myelin sheaths in the white matter of the brain. To date, the etiology of these disorders is not well known and no effective treatments are currently available. Therefore, further research is needed to gain a better understand and treat these patients. To accomplish this goal, it is necessary to have appropriate animal models that closely resemble the pathophysiology of these diseases...
July 17, 2017: Current Neuropharmacology
https://www.readbyqxmd.com/read/28713886/a-new-tetrapodal-3-hydroxy-4-pyridinone-ligand-for-complexation-of-89-zirconium-for-positron-emission-tomography-pet-imaging
#18
Christian Buchwalder, Cristina Rodríguez-Rodríguez, Paul Schaffer, Stoyan K Karagiozov, Katayoun Saatchi, Urs O Häfeli
Zirconium-89 ((89)Zr) is an ideal radiometal isotope for antibody-based positron emission tomography (immunoPET) as its physical half-life (3.27 days) is a good match with the biological half-life of larger molecular weight targeting molecules, such as antibodies (3-4 days), and its positron emission (BR = 100% EC/β(+), Eβ(+),avg = 395.5 keV) is suited for high resolution PET imaging. Concerns over the in vivo stability of the most commonly used (89)Zr-chelator, desferrioxamine B (DFO), have spurred efforts into the development of alternative (89)Zr-chelators that withstand the release of osteophilic (89)Zr(4+)...
July 17, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/28713408/transcriptome-analyses-shed-new-insights-into-primary-metabolism-and-regulation-of-blumeria-graminis-f-sp-tritici-during-conidiation
#19
Fan-Song Zeng, Fabrizio Menardo, Min-Feng Xue, Xue-Jiang Zhang, Shuang-Jun Gong, Li-Jun Yang, Wen-Qi Shi, Da-Zhao Yu
Conidia of the obligate biotrophic fungal pathogen Blumeria graminis f. sp. tritici (Bgt) play a vital role in its survival and rapid dispersal. However, little is known about the genetic basis for its asexual reproduction. To uncover the primary metabolic and regulatory events during conidiation, we sequenced the transcriptome of Bgt epiphytic structures at 3 (vegetative hyphae growth), 4 (foot cells initiation), and 5 (conidiophore erection) days post-inoculation (dpi). RNA-seq analyses identified 556 and 404 (combined 685) differentially expressed genes (DEGs) at 4 and 5 dpi compared with their expression levels at 3 dpi, respectively...
2017: Frontiers in Plant Science
https://www.readbyqxmd.com/read/28712303/mn-ii-oxidation-by-the-multicopper-oxidase-complex-mnx-a-coordinated-two-stage-mn-ii-iii-and-mn-iii-iv-mechanism
#20
Alexandra V Soldatova, Christine A Romano, Lizhi Tao, Troy A Stich, William H Casey, R David Britt, Bradley M Tebo, Thomas G Spiro
The bacterial manganese oxidase MnxG of the Mnx protein complex is unique among multicopper oxidases (MCOs) in carrying out a two-electron metal oxidation, converting Mn(II) to MnO2 nanoparticles. The reaction occurs in two stages: Mn(II)→Mn(III) and Mn(III)→MnO2. In a companion study,(1) we show that the electron transfer from Mn(II) to the low-potential type 1 Cu of MnxG requires an activation step, likely forming a hydroxide bridge at a dinuclear Mn(II) site. Here we study the second oxidation step, using pyrophosphate (PP) as a Mn(III) trap...
July 17, 2017: Journal of the American Chemical Society
keyword
keyword
24243
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"