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https://www.readbyqxmd.com/read/28823019/sensitive-and-selective-turn-on-chemodosimetric-probes-for-fe-3-based-on-a-skeleton-of-2-hydroxy-1-naphthaldehyde
#1
Ghulam Shabir, Aamer Saeed, Pervaiz Ali Channar, Fayaz Ali Larik, Tanzeela AbdulFatah
A naked-eye colored chemodosimeteric probes 4a-f, based on Schiff-azo dye conjugates were synthesized and characterized. All compounds 4a-f exhibited excellent selectivity and high sensitivity in absorbance toward detection of Fe(3+) in alcoholic solutions under neutral pH conditions. The detection limit of the probe was shown to be up to 0.05 ppm. A simple paper test strip system for the rapid monitoring of Fe(3+) was developed, indicating their convenient use in environmental samples. Electrochemical analysis of metal free conjugates and iron chelated probes confirmed the chelation of ligands...
August 19, 2017: Journal of Fluorescence
https://www.readbyqxmd.com/read/28822260/bioavailability-and-chronic-toxicity-of-bismuth-citrate-to-earthworm-eisenia-andrei-exposed-to-natural-sandy-soil
#2
Zohra Omouri, Jalal Hawari, Michel Fournier, Pierre Yves Robidoux
The present study describes bioavailability and chronic effects of bismuth to earthworms Eisenia andrei using OECD reproduction test. Adult earthworms were exposed to natural sandy soil contaminated artificially by bismuth citrate. Average total concentrations of bismuth in soil recovered by HNO3 digestion ranged from 75 to 289mg/kg. Results indicate that bismuth decreased significantly all reproduction parameters of Eisenia andrei at concentrations ≥ 116mg/kg. However, number of hatched cocoons and number of juveniles seem to be more sensitive than total number of cocoons, as determined by IC50; i...
August 16, 2017: Ecotoxicology and Environmental Safety
https://www.readbyqxmd.com/read/28822250/polyaspartate-extraction-of-cadmium-ions-from-contaminated-soil-evaluation-and-optimization-using-central-composite-design
#3
Nuhu Dalhat Mu'azu, Shamsudeen A Haladu, Nabeel Jarrah, Mukarram Zubair, Mohammad H Essa, Shaikh A Ali
The occurrences of heavy metal contaminated sites and soils and the need for devising environmentally friendly solutions have become global issues of serious concern. In this study, polyaspartate (a highly biodegradable agent) was synthesized using L-Aspartic acid via a new modified thermal procedure and employed for extraction of cadmium ions (Cd) from contaminated soil. Response surface methodology approach using 3(5) full faced centered central composite design was employed for modeling, evaluating and optimizing the influence of polyaspartate concentration (36-145mM), polyaspartate/soil ratio (5-25), initial heavy metal concentration (100-500mg/kg), initial pH (3-6) and extraction time (6-24h) on Cd ions extracted into the polyaspartate solution and its residual concentration in the treated soil...
August 8, 2017: Journal of Hazardous Materials
https://www.readbyqxmd.com/read/28822236/synthesis-structural-studies-and-biological-activity-of-novel-cu-ii-complexes-with-thiourea-derivatives-of-4-azatricyclo-5-2-1-0-2-6-dec-8-ene-3-5-dione
#4
Aleksandra Drzewiecka-Antonik, Paweł Rejmak, Marcin T Klepka, Anna Wolska, Piotr Pietrzyk, Karolina Stępień, Giuseppina Sanna, Marta Struga
The new Cu(II) complexes of 1/2/3-(bromophenyl)-3-(1,7,8,9-tetramethyl-3,5-dioxo-4-azatricyclo[5.2.1.0(2,6)]dec-8-en-4-yl)thiourea derivatives have been synthesized. The spectroscopic studies together with density functional theory calculations of Cu(II) complexes revealed that two parent ligands coordinate to the copper cation in bidentate fashion via thiocarbonyl S and deprotonated N atoms forming rarely observed four-membered chelate ring, with nearly planar [CuN2S2] moiety. In solid state, the mononuclear complex is formed for thiourea derivative with 3-bromophenyl, whereas for Cu(II) connection with 2- and 4-bromophenyl-thioureas the formation of dinuclear complexes is observed, the latter formed by the stacking of mononuclear complexes...
August 9, 2017: Journal of Inorganic Biochemistry
https://www.readbyqxmd.com/read/28821793/molecular-mechanisms-of-atlastin-mediated-er-membrane-fusion-revealed-by-a-fret-based-single-vesicle-fusion-assay
#5
Kyung Tae Kim, Yeojin Moon, Yunsu Jang, Kang Taek Lee, Changwook Lee, Youngsoo Jun, Sanghwa Lee
Homotypic fusion of endoplasmic reticulum membranes is driven by atlastin GTPases; however, the underlying mechanism remains largely unknown. Here, using a FRET-based single-vesicle fusion assay with liposomes bearing the yeast atlastin Sey1p, we investigated the molecular mechanisms of atlastin-mediated membrane tethering and fusion. Although Sey1p-bearing proteoliposomes frequently underwent membrane tethering in a GTP hydrolysis-dependent manner as reported in studies using bulk assays, only a small fraction of the tethered liposomes proceeded to fusion...
August 18, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28821633/cell-autonomous-cytotoxicity-of-type-i-interferon-response-via-induction-of-endoplasmic-reticulum-stress
#6
Chrysovalantou Mihailidou, Athanasios G Papavassiliou, Hippokratis Kiaris
The interaction of IFN with specific membrane receptors that transduce death-inducing signals is considered to be the principle mechanism of IFN-induced cytotoxicity. In this study, the classic non-cell-autonomous cytotoxicity of IFN was augmented by cell-autonomous mechanisms that operated independently of the interaction of IFN with its receptors. Cells primed to produce IFN by 5-azacytidine (5-aza) underwent endoplasmic reticulum (ER) stress. The chemical chaperones tauroursodeoxycholate (TUDCA) and 4-phenylbutyrate (4-PBA), as well as the iron chelator ciclopirox (CPX), which reduces ER stress, alleviated the cytotoxicity of 5-aza...
August 17, 2017: FASEB Journal: Official Publication of the Federation of American Societies for Experimental Biology
https://www.readbyqxmd.com/read/28821101/cholesteric-film-of-cu-ii-doped-cellulose-nanocrystals-for-colorimetric-sensing-of-ammonia-gas
#7
Shidong Dai, Nana Prempeh, Dagang Liu, Yimin Fan, Mingyue Gu, Yu Chang
With the increasing demand of environmental monitoring for toxic and odorous ammonia gas it is desired to develop specific green, cost-effective and in situ passive colorimetric alternatives to current complex instrumentations. In this work, we designed an ammonia gas sensor based on cholesteric liquid crystal films of copper(II)-doped cellulose nanocrystals (CNCCu(II)) whose structure, optical and sensing properties were investigated. The hybrid films using the low doping Cu(II) as a color-tuning agent inherited the chiral nematic signature and optical activity of CNCs, suggesting a strong chelation between copper ions and negatively charged CNCs...
October 15, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/28821044/removal-of-heavy-metal-ions-by-magnetic-chitosan-nanoparticles-prepared-continuously-via-high-gravity-reactive-precipitation-method
#8
Hong-Lei Fan, Shao-Feng Zhou, Wei-Zhou Jiao, Gui-Sheng Qi, You-Zhi Liu
This study aimed to provide a continuous method for the preparation of magnetic Fe3O4/Chitosan nanoparticles (Fe3O4/CS NPs) that can be applied to efficient removal of heavy metal ions from aqueous solution. Using a novel impinging stream-rotating packed bed, the continuous preparation of Fe3O4/CS NPs reached a theoretical production rate of 3.43kg/h. The as-prepared Fe3O4/CS NPs were quasi-spherical with average diameter of about 18nm and saturation magnetization of 33.5emu/g. Owing to the strong metal chelating ability of chitosan, the Fe3O4/CS NPs exhibited better adsorption capacity and faster adsorption rates for Pb(II) and Cd(II) than those of pure Fe3O4...
October 15, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/28820939/attachment-of-a-ruii-complex-to-a-self-folding-hexaamide-deep-cavitand
#9
Saša Korom, Pablo Ballester
We report the design, synthesis and characterization of a new RuII metallocavitand that is catalytically active in alkene epoxidation reactions. The elaboration of the resorcin[4]arene's aromatic cavity produced a self-folding, deep hex-aamide cavitand featuring a single diverging terpyridine (tpy) group installed at its upper rim. The construction of the metallocavitand involved the initial chelation of a RuIII chloride complex by the tpy ligand followed by the incorpora-tion of 2-(phenylazo)pyridine (azpy) as an ancillary ligand...
August 18, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28820334/evolutionary-analysis-of-a-novel-zinc-ribbon-in-the-n-terminal-region-of-threonine-synthase
#10
Gurmeet Kaur, Srikrishna Subramanian
Threonine synthase (TS) catalyzes the terminal reaction in the biosynthetic pathway of threonine and requires pyridoxal phosphate as a cofactor. TSs share a common catalytic domain with other fold type II PALP dependent enzymes. TSs are broadly grouped into two classes based on their sequence, quaternary structure, and enzyme regulation. We report the presence of a novel zinc ribbon domain in the N-terminal region preceding the catalytic core in TS. The zinc ribbon domain is present in TSs belonging to both classes...
August 18, 2017: Cell Cycle
https://www.readbyqxmd.com/read/28820224/label-free-fluorescent-immunoassay-for-cu-2-ion-detection-based-on-uv-degradation-of-immunocomplex-and-metal-ion-chelates
#11
Qi Shu, Mengli Liu, Hui Ouyang, Zhifeng Fu
A mouse anti Cu(2+)-EDTA monoclonal antibody was used to capture EDTA chelated Cu(2+) ions. Then UV radiation was utilized to degrade immunocomplex and Cu(2+)-EDTA chelates to release free Cu(2+) ions. Based on their quenching effect to the fluorescent emission of CdSe/ZnS quantum dots, the released Cu(2+) ions could be detected with ideal specificity and high sensitivity.
August 18, 2017: Nanoscale
https://www.readbyqxmd.com/read/28820199/tuning-the-copper-ii-coordination-properties-of-cyclam-by-subtle-chemical-modifications
#12
Nathalie Camus, Nathalie Le Bris, Selbi Nuryyeva, Matthieu Chessé, David Esteban-Gómez, Carlos Platas-Iglesias, Raphaël Tripier, Mourad Elhabiri
The acid-base and copper(ii) coordination properties of three previously described cyclam derivatives are reported. Potentiometry, mass spectrometry, UV-vis absorption spectroscopy, electrochemistry and theoretical calculations were combined to investigate the protonation and binding properties of Bn-cyclam-EtOH (L1), oxo-cyclam-EtOH (L2) and oxo-Bn-cyclam-EtOH (L3). These three cyclams are C-functionalized by a hydroxyethyl pendant arm and display either one N-benzyl group and/or an amide replacing one macrocyclic secondary amine...
August 18, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/28819732/erratum-to-fructose-1-6-bisphosphate-reverts-iron-induced-phenotype-of-hepatic-stellate-cells-by-chelating-ferrous-ions
#13
Henrique Bregolin Dias, Gabriele Catyana Krause, Eamin Daidrê Squizani, Kelly Goulart Lima, Aline Daniele Schuster, Leonardo Pedrazza, Bruno de Souza Basso, Bianca Andrade Martha, Fernanda Cristina de Mesquita, Fernanda Bordignon Nunes, Márcio Vinícius Fagundes Donadio, Jarbas Rodrigues de Oliveira
No abstract text is available yet for this article.
August 17, 2017: Biometals: An International Journal on the Role of Metal Ions in Biology, Biochemistry, and Medicine
https://www.readbyqxmd.com/read/28819397/iron-chelators-and-exogenic-photosensitizers-synergy-through-oxidative-stress-gene-expression
#14
Anna Mrozek-Wilczkiewicz, Katarzyna Malarz, Marzena Rams-Baron, Maciej Serda, Daniela Bauer, Franz-Peter Montforts, Alicja Ratuszna, Thomas Burley, Jaroslaw Polanski, Robert Musiol
In non-invasive anticancer photodynamic therapy (PDT), a nontoxic photosensitizer (PS), which is activated by visible light, is used as a magic bullet that selectively destroys cancer cells. Recently, we described the combined therapy of 5-aminolevulinic acid (ALA-PDT) with thiosemicarbazone (TSC), i.e. an iron-chelating agent. This resulted in a strong synergistic effect. Herein, we investigated a novel strategy using a combination of PDT consist of the xenobiotic-porphyrin type PS with TSC. We observed a synergistic effect for all of the pairs of TSC-PS...
2017: Journal of Cancer
https://www.readbyqxmd.com/read/28818756/interactions-between-aluminium-iron-and-silicon-in-cucumber-sativus-l-grown-under-acidic-conditions
#15
Nikolai P Bityutskii, Kirill L Yakkonen, Anastasiya I Petrova, Alexey L Shavarda
Aluminium (Al) is one of the major stressors for plants in acidic soils, negatively affecting plant growth and nutrient balances. Significant efforts have been undertaken to understand mechanisms of Al tolerance in plants. However, little is known of the relevance of iron (Fe) and silicon (Si) nutrition under Al stress conditions. The objectives of this study were to determine whether effects induced by Fe and Si are of importance for limitation of Al moving via xylem in plants (Cucumis sativus L.). Cucumber plants (cv...
August 4, 2017: Journal of Plant Physiology
https://www.readbyqxmd.com/read/28818403/heavy-metal-levels-in-patients-with-ineffective-erythropoiesis
#16
Turan Bayhan, Şule Ünal, Eyüp Çırak, Onur Erdem, Cemal Akay, Orhan Gürsel, İbrahim Eker, Erdem Karabulut, Fatma Gümrük
OBJECTIVES: Iron is taken into enterocytes at the duodenum via apical divalent metal-ion transporter 1 protein. Besides iron, divalent metal-ion transporter 1 also transports other divalent metals. We aimed to investigate blood heavy metal levels in patients with ineffective erythropoiesis. METHODS: Blood levels of heavy metals including Pb, Al, Cd, Cr, Co, Cu, and Zn were measured in patients with thalassemia major (TM), thalassemia intermedia (TI), congenital dyserythropoietic anemia (CDA), and age- and sex-matched healthy controls...
August 2, 2017: Transfusion and Apheresis Science
https://www.readbyqxmd.com/read/28818264/the-potential-management-of-oral-candidiasis-using-anti-biofilm-therapies
#17
Warren Chanda, Thomson P Joseph, Wendong Wang, Arshad A Padhiar, Mintao Zhong
Candida albicans is a minor component of the oral microbiota and an opportunistic pathogen that takes advantage of the immunocompromised host and causes oral mucositis and oral candidiasis. This organism is able to undergo phenotypic modification from a yeast to hyphae growth phase, one of the key arsenals for immune cell evasion, tissue invasion and biofilm formation. The latter property coupled with overgrowth and immune compromising factors such as HIV/AIDS, cancer treatments, organ transplantation, diabetes, corticosteroid use, dentures, and broad-spectrum antibiotic use have modified the fungus from a normal component of the microflora to a foe of an oral cavity and resulting in reduced sensitivity towards commonly utilised antifungal agents...
September 2017: Medical Hypotheses
https://www.readbyqxmd.com/read/28817776/electrophilic-cyclization-of-phenylalkynediols-to-naphthyl-aryl-iodonium-triflates-with-chelating-hydroxyls-preparation-and-x-ray-analyses
#18
Robert James Hinkle, Sarah E Bredenkamp, Robert David Pike, Seong Ik Cheon
Alkynediols containing one propargylic alcohol as well as a second alcohol, which is propargylic or homopropargylic, react with PhI(+)CN(-)OTf (Stang's reagent) or 3,5-(CF3)2C6H3I(+)CN(-)OTf to afford naphthyl(aryl)iodonium triflates. The reaction occurs at room temperature over the course of 6-12 hours and provides 36-82% yields of microcrystalline solids. Slow diffusion of Et2O into CH3CN solutions of the salts afforded X-ray quality crystals of five compounds with hydroxyl groups forming five- and six-membered chelation complexes with the iodine atom...
August 17, 2017: Journal of Organic Chemistry
https://www.readbyqxmd.com/read/28817264/structural-diversities-in-heterometallic-mn-ca-cluster-chemistry-from-the-use-of-salicylhydroxamic-acid-mn-iii-4ca2-mn-ii-iii-6ca2-mn-iii-iv-8ca-and-mn-iii-8ca2-complexes-with-relevance-to-both-high-and-low-valent-states-of-the-oxygen-evolving-complex
#19
Alysha A Alaimo, Evangelia S Koumousi, Luís Cunha-Silva, Laura J McCormick, Simon J Teat, Vassilis Psycharis, Catherine P Raptopoulou, Shreya Mukherjee, Chaoran Li, Sayak Das Gupta, Albert Escuer, George Christou, Theocharis C Stamatatos
One-pot reactions between the [Mn3O(O2CPh)6(py)x](+/0) triangular precursors and either CaBr2·xH2O or CaCl2·6H2O, in the presence of salicylhydroxamic acid (shaH2), have afforded the heterometallic complexes [Mn(III)4Ca2(O2CPh)4(shi)4(H2O)3(Me2CO)] (1) and (pyH)[Mn(II)2Mn(III)4Ca2Cl2(O2CPh)7(shi)4(py)4] (2), respectively, in good yields. Further reactions but using a more flexible synthetic scheme comprising the Mn(NO3)2·4H2O/Ca(NO3)2·4H2O and Mn(O2CPh)2·2H2O/Ca(ClO4)2·4H2O "metal blends" and shaH2, in the presence of external base NEt3, led to the new complexes (NHEt3)2[Mn(III)4Mn(IV)4Ca(OEt)2(shi)10(EtOH)2] (3) and (NHEt3)4[Mn(III)8Ca2(CO3)4(shi)8] (4), respectively...
August 17, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28817213/bismuthanes-as-hemilabile-donors-in-an-o2-activating-palladium-0-complex
#20
Karolin Materne, Beatrice Braun-Cula, Christian Herwig, Nicolas Frank, Christian Limberg
A xanthene-based bismuthane/phosphane chelating ligand has been accessed that has enabled the synthesis of a palladium(0) bismuthane complex. The bismuthane donor proved to be hemilabile as it switched to a dangling position upon addition of O2 that gave a palladium(II) peroxide complex. Unlike the corresponding 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (Xantphos) palladium peroxide, the bismuth analogue could be employed for catalytic phosphane oxidation and oxidative phenol coupling.
August 17, 2017: Chemistry: a European Journal
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