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  1 / 1711 MEDLINE  
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[PMID]:28640600
[Au] Autor:Plapp BV; Savarimuthu BR; Ferraro DJ; Rubach JK; Brown EN; Ramaswamy S
[Ad] Endereço:Department of Biochemistry, The University of Iowa , Iowa City, Iowa 52242, United States.
[Ti] Título:Horse Liver Alcohol Dehydrogenase: Zinc Coordination and Catalysis.
[So] Source:Biochemistry;56(28):3632-3646, 2017 Jul 18.
[Is] ISSN:1520-4995
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:During catalysis by liver alcohol dehydrogenase (ADH), a water bound to the catalytic zinc is replaced by the oxygen of the substrates. The mechanism might involve a pentacoordinated zinc or a double-displacement reaction with participation by a nearby glutamate residue, as suggested by studies of human ADH3, yeast ADH1, and some other tetrameric ADHs. Zinc coordination and participation of water in the enzyme mechanism were investigated by X-ray crystallography. The apoenzyme and its complex with adenosine 5'-diphosphoribose have an open protein conformation with the catalytic zinc in one position, tetracoordinated by Cys-46, His-67, Cys-174, and a water molecule. The bidentate chelators 2,2'-bipyridine and 1,10-phenanthroline displace the water and form a pentacoordinated zinc. The enzyme-NADH complex has a closed conformation similar to that of ternary complexes with coenzyme and substrate analogues; the coordination of the catalytic zinc is similar to that found in the apoenzyme, except that a minor, alternative position for the catalytic zinc is ∼1.3 Šfrom the major position and closer to Glu-68, which could form the alternative coordination to the catalytic zinc. Complexes with NADH and N-1-methylhexylformamide or N-benzylformamide (or with NAD and fluoro alcohols) have the classical tetracoordinated zinc, and no water is bound to the zinc or the nicotinamide rings. The major forms of the enzyme in the mechanism have a tetracoordinated zinc, where the carboxylate group of Glu-68 could participate in the exchange of water and substrates on the zinc. Hydride transfer in the Michaelis complexes does not involve a nearby water.
[Mh] Termos MeSH primário: Álcool Desidrogenase/metabolismo
Fígado/enzimologia
Zinco/metabolismo
[Mh] Termos MeSH secundário: 2,2'-Dipiridil/metabolismo
Adenosina Difosfato Ribose/metabolismo
Álcool Desidrogenase/química
Animais
Domínio Catalítico
Cristalografia por Raios X
Formamidas/metabolismo
Cavalos
Cinética
Fígado/metabolismo
Modelos Moleculares
NAD/metabolismo
Fenantrolinas/metabolismo
Ligação Proteica
Conformação Proteica
Água/química
Água/metabolismo
Zinco/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Formamides); 0 (N-benzylformamide); 0 (Phenanthrolines); 059QF0KO0R (Water); 0U46U6E8UK (NAD); 20762-30-5 (Adenosine Diphosphate Ribose); 551W113ZEP (2,2'-Dipyridyl); EC 1.1.1.1 (Alcohol Dehydrogenase); J41CSQ7QDS (Zinc); W4X6ZO7939 (1,10-phenanthroline)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170804
[Lr] Data última revisão:
170804
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170623
[St] Status:MEDLINE
[do] DOI:10.1021/acs.biochem.7b00446


  2 / 1711 MEDLINE  
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[PMID]:28485964
[Au] Autor:Zhang Y; Wang L; Zhang Q; Zhu G; Zhang Z; Zhou X; Chen Y; Lu T; Tang W
[Ad] Endereço:School of Basic Science, China Pharmaceutical University , 639 Longmian Avenue, Nanjing, Jiangsu 211198, China.
[Ti] Título:Potent Pan-Raf and Receptor Tyrosine Kinase Inhibitors Based on a Cyclopropyl Formamide Fragment Overcome Resistance.
[So] Source:J Chem Inf Model;57(6):1439-1452, 2017 Jun 26.
[Is] ISSN:1549-960X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:While selective BRaf inhibitors have been proven effective clinically, acquired resistance rapidly develops through reactivation of the mitogen-activated protein kinase (MAPK) pathway. Simultaneous targeting of multiple nodes in the pathway offers the prospect of enhanced efficacy as well as reduced potential for acquired resistance. Replacement pyridine group of Y-1 by a cyclopropyl formamide group afforded I-01 as a novel multitargeted kinase inhibitor template. I-01 displayed enzyme potency against Pan-Raf and receptor tyrosine kinases (RTKs). Based on the binding mode of I-01, analogues I-02-I-18 were designed and synthesized. The most promising compound I-16 potently inhibits all subtypes of Rafs with IC values of 3.49 (BRaf ), 8.86 (ARaf), 5.78 (BRaf ), and 1.65 nM (CRaf), respectively. I-16 not only exhibit comparable antiproliferative activities with positive control compounds against HepG2, SW579, MV4-11, and COLO205 cell lines, but also suppress the proliferation of melanoma SK-MEL-2 harboring overexpressed BRaf with IC values of 0.93 µM. The Western blot results for the ERK inhibition in human melanoma SK-MEL-2 cell lines show that I-16 inhibits the proliferation of SK-MEL-2 cell lines without paradoxical activation of ERK, which support the hypothesis that the inhibition of Pan-Raf and RTKs might be a tractable strategy to overcome the resistance of melanoma induced by the therapy with the current selective BRaf inhibitors.
[Mh] Termos MeSH primário: Desenho de Drogas
Resistência a Medicamentos Antineoplásicos/efeitos dos fármacos
Formamidas/química
Formamidas/farmacologia
Receptores Proteína Tirosina Quinases/antagonistas & inibidores
Quinases raf/antagonistas & inibidores
[Mh] Termos MeSH secundário: Linhagem Celular Tumoral
Proliferação Celular/efeitos dos fármacos
Seres Humanos
Simulação de Dinâmica Molecular
Conformação Proteica
Inibidores de Proteínas Quinases/química
Inibidores de Proteínas Quinases/farmacologia
Receptores Proteína Tirosina Quinases/química
Quinases raf/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Formamides); 0 (Protein Kinase Inhibitors); EC 2.7.10.1 (Receptor Protein-Tyrosine Kinases); EC 2.7.11.1 (raf Kinases)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170921
[Lr] Data última revisão:
170921
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170510
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jcim.6b00795


  3 / 1711 MEDLINE  
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[PMID]:28381768
[Au] Autor:Shibuya H; Nakago T; Inoue S; Hoshino Y; Honda K
[Ad] Endereço:Graduate School of Environment and Information Sciences, Yokohama National University.
[Ti] Título:Tandem Brook Rearrangement/Silicon Polonovski Reaction via Oxidative Generation of Ammonium Ylides.
[So] Source:J Oleo Sci;66(8):833-842, 2017 Aug 01.
[Is] ISSN:1347-3352
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:A tandem Brook rearrangement/silicon Polonovski reaction has been achieved by in situ generation of ammonium ylides via the oxidation of α-silyl-tertiary amines. Furthermore, we found that the oxidation of N-(1-cyano-1-silyl)methyl-tertiary amines with peracids induced the tandem Brook rearrangement/silicon Polonovski reaction/fragmentation to give formamide derivatives in moderate yields.
[Mh] Termos MeSH primário: Aminas/química
Compostos de Amônio/síntese química
Formamidas/síntese química
Silício/química
[Mh] Termos MeSH secundário: Remoção de Radical Alquila
Fenômenos de Química Orgânica
Oxirredução
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amines); 0 (Ammonium Compounds); 0 (Formamides); 4781T907ZS (formamide); Z4152N8IUI (Silicon)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171010
[Lr] Data última revisão:
171010
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170407
[St] Status:MEDLINE
[do] DOI:10.5650/jos.ess16022


  4 / 1711 MEDLINE  
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[PMID]:28065577
[Au] Autor:Zhang X; Voronov S; Mussa N; Li Z
[Ad] Endereço:Department of Biological Process Development, Bristol-Myers Squibb, USA. Electronic address: Xin.Zhang4@bms.com.
[Ti] Título:A novel reagent significantly improved assay robustness in imaged capillary isoelectric focusing.
[So] Source:Anal Biochem;521:1-7, 2017 Mar 15.
[Is] ISSN:1096-0309
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Imaged Capillary Isoelectric Focusing (icIEF) has been used as primary method for charge variants analysis of therapeutic antibodies and proteins [1], [9]. Proteins tend to precipitate around their pI values during focusing [14], which directly affects the reproducibility of their charge profiles. Protein concentration, focusing time and various supplementing additives are key parameters to minimize the protein precipitation and aggregation. Urea and sucrose are common additives to reduce protein aggregation, solubilize proteins in sample matrix and therefore improve assay repeatability [15]. However some proteins and antibodies are exceptions, we found urea and sucrose are not sufficient for a typical fusion protein (Fusion protein A) in icIEF assay and high variability is observed. We report a novel reagent, formamide, significantly improved reproducibility of protein charge profiles. Our results show formamide is a good supplementary reagent to reduce aggregation and stabilize proteins in isoelectric focusing. We further confirmed the method robustness, linearity, accuracy and precision after introducing the new reagent; extremely tight pI values, significantly improved method precision and sample on-board stability are achieved by formamide. Formamide is also proven to be equally functional to multiple antibodies as urea, which makes it an extra tool in icIEF method development.
[Mh] Termos MeSH primário: Bioensaio/métodos
Eletroforese Capilar/métodos
Formamidas/química
Focalização Isoelétrica/métodos
Laboratórios/normas
Imagem Molecular/métodos
Proteínas/análise
[Mh] Termos MeSH secundário: Seres Humanos
Isoformas de Proteínas
Proteínas/metabolismo
Reprodutibilidade dos Testes
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Formamides); 0 (Protein Isoforms); 0 (Proteins); 4781T907ZS (formamide)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170508
[Lr] Data última revisão:
170508
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170110
[St] Status:MEDLINE


  5 / 1711 MEDLINE  
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[PMID]:27959490
[Au] Autor:Pujari SS; Tretyakova N
[Ad] Endereço:Department of Medicinal Chemistry and Masonic Cancer Center, University of Minnesota , Minneapolis, Minnesota 55455, United States.
[Ti] Título:Chemical Biology of N -Substituted Formamidopyrimidine DNA Adducts.
[So] Source:Chem Res Toxicol;30(1):434-452, 2017 01 17.
[Is] ISSN:1520-5010
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:DNA nucleobases are the prime targets for chemical modifications by endogenous and exogenous electrophiles. Alkylation of the N7 position of guanine and adenine in DNA triggers base-catalyzed imidazole ring opening and the formation of N -substituted formamidopyrimidine (N -R-FAPy) lesions. Me-FAPy-dG adducts induced by exposure to methylating agents and AFB-FAPy-dG lesions formed by aflatoxin B have been shown to persist in cells and to contribute to toxicity and mutagenicity. In contrast, the biological outcomes of other N -substituted FAPy lesions have not been fully elucidated. To enable their structural and biological evaluation, N -R-FAPy adducts must be site-specifically incorporated into synthetic DNA strands using phosphoramidite building blocks, which can be complicated by their unusual structural complexity. N -R-FAPy exist as a mixture of rotamers and can undergo isomerization between α, ß anomers and furanose-pyranose forms. In this Perspective, we will discuss the main types of N -R-FAPy adducts and summarize the strategies for their synthesis and structural elucidation. We will also summarize the chemical biology studies conducted with N -R-FAPy-containing DNA to elucidate their effects on DNA replication and to identify the mechanisms of N -R-FAPy repair.
[Mh] Termos MeSH primário: Adutos de DNA/química
Formamidas/química
Pirimidinas/química
[Mh] Termos MeSH secundário: Animais
Adutos de DNA/metabolismo
Reparo do DNA
Formamidas/metabolismo
Seres Humanos
Oligodesoxirribonucleotídeos/química
Oligodesoxirribonucleotídeos/metabolismo
Pirimidinas/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL
[Nm] Nome de substância:
0 (DNA Adducts); 0 (Formamides); 0 (Oligodeoxyribonucleotides); 0 (Pyrimidines)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170510
[Lr] Data última revisão:
170510
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161214
[St] Status:MEDLINE
[do] DOI:10.1021/acs.chemrestox.6b00392


  6 / 1711 MEDLINE  
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[PMID]:27860420
[Au] Autor:Luo R; Lin X; Chen Y; Zhang W; Zhou X; Ji H
[Ad] Endereço:School of Chemistry, Key Laboratory of Low-Carbon Chemistry & Energy Conservation of Guangdong Province, Sun Yat-sen University, Guangzhou, 510275, P. R. China.
[Ti] Título:Cooperative Catalytic Activation of Si-H Bonds: CO -Based Synthesis of Formamides from Amines and Hydrosilanes under Mild Conditions.
[So] Source:ChemSusChem;10(6):1224-1232, 2017 Mar 22.
[Is] ISSN:1864-564X
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:A simple cooperative catalytic system was successfully developed for the solvent-free N-formylation of amines with CO and hydrosilanes under ambient conditions, which was composed of a Zn(salen) catalyst and quaternary ammonium salt. These commercially available binary components activated the Si-H bonds effectively, owing to the intermolecular synergistic effect between Lewis base and transition metal center (LB-TM), and subsequently facilitated the insertion of CO to form the active silyl formats, thereby leading to excellent catalytic performance at a low catalyst loading. Furthermore, the bifunctional Zn(salen) complexes, with two imidazolium-based ionic-liquid (IL) units at the 3,3'-position of salen ligand, acted as intramolecularly cooperative catalysts, and the solvent-regulated separation resulted in facile catalyst recycling and reuse.
[Mh] Termos MeSH primário: Aminas/química
Formamidas/química
Formamidas/síntese química
Hidrogênio/química
Silanos/química
Silício/química
[Mh] Termos MeSH secundário: Catálise
Técnicas de Química Sintética
Etilenodiaminas/química
Compostos Organometálicos/química
Solventes/química
Zinco/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amines); 0 (Ethylenediamines); 0 (Formamides); 0 (Organometallic Compounds); 0 (Silanes); 0 (Solvents); 7YNJ3PO35Z (Hydrogen); 94-93-9 (disalicylaldehyde ethylenediamine); J41CSQ7QDS (Zinc); Z4152N8IUI (Silicon)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170627
[Lr] Data última revisão:
170627
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161119
[St] Status:MEDLINE
[do] DOI:10.1002/cssc.201601490


  7 / 1711 MEDLINE  
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[PMID]:27856300
[Au] Autor:Canale TD; Sen D
[Ad] Endereço:Department of Molecular Biology & Biochemistry, Simon Fraser University, Burnaby, British Columbia, V5A 1S6, Canada.
[Ti] Título:Hemin-utilizing G-quadruplex DNAzymes are strongly active in organic co-solvents.
[So] Source:Biochim Biophys Acta;1861(5 Pt B):1455-1462, 2017 05.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The widespread use of organic solvents in industrial processes has focused in recent years on the utility of "green" solvents - those with less harmful environmental, health, and safety properties - such as methanol and formamide. However, protein enzymes, regarded as green catalysts, are often incompatible with organic solvents. Herein, we have explored the oxidative properties of a Fe(III)-heme, or hemin, utilizing catalytic DNA (heme·DNAzyme) in different green solvent-water mixtures. We find that the peroxidase and peroxygenase activities of the heme·DNAzyme are strongly enhanced in 20-30% v/v methanol or formamide, relative to water alone. Protic solvent content of >30% v/v gradually diminishes heme·DNAzyme catalytic activity; however, the heme·DNAzyme is still active in as high as 80% v/v methanol. In contrast to protic solvents, aqueous dimethylformamide solutions largely inhibit heme·DNAzyme activity. In view of the strong catalytic activity of heme·DNAzyme in aqueous methanol, we were able to determine that a 60% v/v methanol-water mixture gives the most optimal yield of the dibenzothiophene sulfoxide (DBTO) oxidation product of petroleum-derived dibenzothiophene (DBT). The high product yield reflects both DNAzyme catalysis and a high substrate availability. Overall, these results emphasize the excellent promise of G-quadruplex forming DNA catalysts in application to "greener" industrial chemistry. This article is part of a Special Issue entitled "G-quadruplex" Guest Editor: Dr. Concetta Giancola and Dr. Daniela Montesarchio.
[Mh] Termos MeSH primário: DNA Catalítico/metabolismo
Quadruplex G
Guanosina/metabolismo
Hemina/metabolismo
Oligonucleotídeos/metabolismo
Compostos Orgânicos/química
Solventes/química
[Mh] Termos MeSH secundário: Sítios de Ligação
Catálise
Dicroísmo Circular
DNA Catalítico/química
Dimetilformamida/química
Ativação Enzimática
Formamidas/química
Guanosina/química
Hemina/química
Ligantes
Metanol/química
Oligonucleotídeos/química
Oxirredução
Ligação Proteica
Espectrofotometria Ultravioleta
Relação Estrutura-Atividade
Água/química
terc-Butil Álcool/química
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (DNA, Catalytic); 0 (Formamides); 0 (Ligands); 0 (Oligonucleotides); 0 (Organic Chemicals); 0 (Solvents); 059QF0KO0R (Water); 12133JR80S (Guanosine); 4781T907ZS (formamide); 743LRP9S7N (Hemin); 8696NH0Y2X (Dimethylformamide); MD83SFE959 (tert-Butyl Alcohol); Y4S76JWI15 (Methanol)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171016
[Lr] Data última revisão:
171016
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161119
[St] Status:MEDLINE


  8 / 1711 MEDLINE  
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[PMID]:27818266
[Au] Autor:Malo C; Crichton EG; Skidmore JA
[Ad] Endereço:Camel Reproduction Centre, PO Box 79914, Dubai, United Arab Emirates. Electronic address: clara@camelreproductioncenter.ae.
[Ti] Título:Optimization of the cryopreservation of dromedary camel semen: Cryoprotectants and their concentration and equilibration times.
[So] Source:Cryobiology;74:141-147, 2017 Feb.
[Is] ISSN:1090-2392
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Research into an optimal cryoprotectant, its concentration and equilibration time underlies the successful cryopreservation of dromedary camel spermatozoa. This study assessed the cryo-efficiency of different cryoprotectants, their concentration and equilibration time and any interactions. In experiment 1, semen samples (n = 4 males; 2 ejaculates/male) were frozen using Green Buffer containing one of four cryoprotectants (3% glycerol, ethylene glycol, methyl formamide, dimethyl sulfoxide) and using 4 equilibration times (10 min, 0.5, 1 and 2 h). Glycerol and ethylene glycol provided the best motility recovery rates and different equilibration times were not significant for any cryoprotectant nor were any interactions noted. However different equilibration times were pertinent for improved kinematic parameters BCF and VSL. In experiment 2, glycerol and ethylene glycol were evaluated at 4 concentrations (1.5, 3, 6, 9%) with 0.5 h equilibration (n = 4 males, 3 ejaculates/male). Sperm motility recoveries, kinematics and acrosome status were assessed. Higher values for LIN and STR were found with ethylene glycol. At 0 and 1 h post thaw 3 and 6% of either cryoprotectant resulted in better motility values than 1.5%. Acrosome integrity was compromised at 9% cryoprotectant. There were interactions between cryoprotectant and concentration in total motility at 0 and 1 h. For glycerol, total motility recoveries were best at 3-9%; for ethylene glycol 1.5-6% were best at 0 h and 3-6% at 1 h. In conclusion, 3-6% glycerol or ethylene glycol offered the best cryoprotection for camel sperm while different equilibration times were not critical.
[Mh] Termos MeSH primário: Camelus
Criopreservação/métodos
Crioprotetores/farmacologia
Preservação do Sêmen/veterinária
Motilidade Espermática/fisiologia
[Mh] Termos MeSH secundário: Acrossomo/efeitos dos fármacos
Acrossomo/fisiologia
Animais
Criopreservação/veterinária
Dimetil Sulfóxido/farmacologia
Etilenoglicol/farmacologia
Formamidas/farmacologia
Congelamento
Glicerol/farmacologia
Masculino
Sêmen/fisiologia
Preservação do Sêmen/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cryoprotective Agents); 0 (Formamides); FC72KVT52F (Ethylene Glycol); PDC6A3C0OX (Glycerol); XPE4G7Y986 (methylformamide); YOW8V9698H (Dimethyl Sulfoxide)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170907
[Lr] Data última revisão:
170907
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161108
[St] Status:MEDLINE


  9 / 1711 MEDLINE  
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[PMID]:28072433
[Au] Autor:Xu Y; Yu HM; Niu YQ; Luo SC; Cheng X
[Ad] Endereço:Institute of Biothermal Science and Technology, University of Shanghai for Science and Technology, Shanghai, China. xuyi@usst.edu.cn.
[Ti] Título:Effects of Superparamagnetic Nanoparticles on Nucleation and Crystal Growth in the Vitrified VS55 During Warming.
[So] Source:Cryo Letters;37(6):448-454, 2016 Nov/Dec.
[Is] ISSN:0143-2044
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:  BACKGROUND:Magnetic nanoparticles (mNPs), once excited by radiofrequency (RF) energy, could heat uniformly and rapidly the vitrified biospecimens. However, there are few studies about the impact of mNPs on crystallization kinetics of vitrified samples. OBJECTIVES: The present work aims to investigate the nucleation and crystal growth in the vitrification solution VS55 with mNPs. MATERIALS AND METHODS: Ferrotec EMG308 superparamagnetic nanoparticles (10 ± 2.5 nm in diameter) coated with an anionic surfactant was used in this study with Fe2+ concentration around 10 mg/ml. The thermal range and the kinetics of nucleation and crystal growth are conducted by DSC and cryomicroscope through different thermal treatments. RESULTS: The fusion heat of VS55+ mNPs is lower than that of VS55 around the rubbery region (-110 to -82 degree C), which suggests the suppression of ice nuclei formation at this temperature range by mNPs. Upon slow cooling especially, much more nuclei in vitrified VS55 forms than that in vitrified VS55+mNPs. The activation energy E of VS55 is lower than that of VS55+mNPs (41.6 kJ/mol vs 46.2 kJ/mol) during devitrification. The presence of mNPs helps to form more stable glass. And these results are consistent with the observations by cryomicroscope. CONCLUSION: The presence of mNPs suppresses ice nuclei formation, especially at slow cooling conditions, and stabilize the cryoprotective solution. The findings can assist the design of magnetic nanoparticles with functional surface coating.
[Mh] Termos MeSH primário: Criopreservação/métodos
Crioprotetores/farmacologia
Dimetil Sulfóxido/farmacologia
Formamidas/farmacologia
HEPES/farmacologia
Nanopartículas de Magnetita
Propilenoglicóis/farmacologia
Vitrificação
[Mh] Termos MeSH secundário: Cristalização
Cinética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cryoprotective Agents); 0 (Formamides); 0 (Magnetite Nanoparticles); 0 (Propylene Glycols); 0 (VS55 solution); RWW266YE9I (HEPES); YOW8V9698H (Dimethyl Sulfoxide)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170619
[Lr] Data última revisão:
170619
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170111
[St] Status:MEDLINE


  10 / 1711 MEDLINE  
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[PMID]:28042825
[Au] Autor:Zhao H; Tang S; Xu X; Du L
[Ad] Endereço:Environment Research Institute, Shandong University, Shanda South Road 27, Jinan 250100, Shandong, China. zhaohl0211@sina.com.
[Ti] Título:Hydrogen Bonding Interaction between Atmospheric Gaseous Amides and Methanol.
[So] Source:Int J Mol Sci;18(1), 2016 Dec 30.
[Is] ISSN:1422-0067
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Amides are important atmospheric organic-nitrogen compounds. Hydrogen bonded complexes of methanol (MeOH) with amides (formamide, -methylformamide, , -dimethylformamide, acetamide, -methylacetamide and , -dimethylacetamide) have been investigated. The carbonyl oxygen of the amides behaves as a hydrogen bond acceptor and the NH group of the amides acts as a hydrogen bond donor. The dominant hydrogen bonding interaction occurs between the carbonyl oxygen and the OH group of methanol as well as the interaction between the NH group of amides and the oxygen of methanol. However, the hydrogen bonds between the CH group and the carbonyl oxygen or the oxygen of methanol are also important for the overall stability of the complexes. Comparable red shifts of the C=O, NH- and OH-stretching transitions were found in these MeOH-amide complexes with considerable intensity enhancement. Topological analysis shows that the electron density at the bond critical points of the complexes fall in the range of hydrogen bonding criteria, and the Laplacian of charge density of the O-H∙∙∙O hydrogen bond slightly exceeds the upper value of the Laplacian criteria. The energy decomposition analysis further suggests that the hydrogen bonding interaction energies can be mainly attributed to the electrostatic, exchange and dispersion components.
[Mh] Termos MeSH primário: Amidas/química
Gases/química
Hidrogênio/química
Metanol/química
[Mh] Termos MeSH secundário: Acetamidas/química
Dimetilformamida/química
Formamidas/química
Ligações de Hidrogênio
Conformação Molecular
Estrutura Molecular
Oxigênio/química
Software
Espectrofotometria Infravermelho
Eletricidade Estática
Termodinâmica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acetamides); 0 (Amides); 0 (Formamides); 0 (Gases); 4781T907ZS (formamide); 7YNJ3PO35Z (Hydrogen); 8696NH0Y2X (Dimethylformamide); 8XOE1JSO29 (acetamide); JCV5VDB3HY (dimethylacetamide); S88TT14065 (Oxygen); V0T777481M (N-methylacetamide); XPE4G7Y986 (methylformamide); Y4S76JWI15 (Methanol)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170418
[Lr] Data última revisão:
170418
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170103
[St] Status:MEDLINE



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