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Pesquisa : D02.241.081.751.080 [Categoria DeCS]
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[PMID]:28858706
[Au] Autor:Modlitbová P; Novotný K; Porízka P; Klus J; Lubal P; Zlámalová-Gargosová H; Kaiser J
[Ad] Endereço:Central European Institute of Technology (CEITEC) Brno University of Technology, Technická 3058/10, 616 00 Brno, Czech Republic. Electronic address: Pavlina.Skarkova@ceitec.vutbr.cz.
[Ti] Título:Comparative investigation of toxicity and bioaccumulation of Cd-based quantum dots and Cd salt in freshwater plant Lemna minor L.
[So] Source:Ecotoxicol Environ Saf;147:334-341, 2018 Jan.
[Is] ISSN:1090-2414
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The purpose of this study was to determine the toxicity of two different sources of cadmium, i.e. CdCl and Cd-based Quantum Dots (QDs), for freshwater model plant Lemna minor L. Cadmium telluride QDs were capped with two coating ligands: glutathione (GSH) or 3-mercaptopropionic acid (MPA). Growth rate inhibition and final biomass inhibition of L. minor after 168-h exposure were monitored as toxicity endpoints. Dose-response curves for Cd toxicity and EC50 values were statistically evaluated for all sources of Cd to uncover possible differences among the toxicities of tested compounds. Total Cd content and its bioaccumulation factors (BAFs) in L. minor after the exposure period were also determined to distinguish Cd bioaccumulation patterns with respect to different test compounds. Laser-Induced Breakdown Spectroscopy (LIBS) with lateral resolution of 200µm was employed in order to obtain two-dimensional maps of Cd spatial distribution in L. minor fronds. Our results show that GSH- and MPA-capped Cd-based QDs have similar toxicity for L. minor, but are significantly less toxic than CdCl . However, both sources of Cd lead to similar patterns of Cd bioaccumulation and distribution in L. minor fronds. Our results are in line with previous reports that the main mediators of Cd toxicity and bioaccumulation in aquatic plants are Cd ions dissolved from Cd-based QDs.
[Mh] Termos MeSH primário: Araceae/efeitos dos fármacos
Cloreto de Cádmio/toxicidade
Compostos de Cádmio/toxicidade
Monitoramento Ambiental/métodos
Pontos Quânticos/toxicidade
Telúrio/toxicidade
Poluentes Químicos da Água/toxicidade
[Mh] Termos MeSH secundário: Ácido 3-Mercaptopropiônico/química
Adsorção
Araceae/crescimento & desenvolvimento
Araceae/metabolismo
Biomassa
Cloreto de Cádmio/metabolismo
Compostos de Cádmio/metabolismo
Água Doce/química
Glutationa/química
Modelos Teóricos
Pontos Quânticos/metabolismo
Telúrio/metabolismo
Poluentes Químicos da Água/química
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cadmium Compounds); 0 (Water Pollutants, Chemical); B03TJ3QU9M (3-Mercaptopropionic Acid); GAN16C9B8O (Glutathione); J6K4F9V3BA (Cadmium Chloride); NQA0O090ZJ (Tellurium); STG188WO13 (cadmium telluride)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170901
[St] Status:MEDLINE


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[PMID]:28448961
[Au] Autor:Divya KP; Dharuman V
[Ad] Endereço:Molecular Electronics Laboratory, Department of Bioelectronics and Biosensors, Science Campus, Alagappa University, Karaikudi 630003, India.
[Ti] Título:Supported binary liposome vesicle-gold nanoparticle for enhanced label free DNA and protein sensing.
[So] Source:Biosens Bioelectron;95:168-173, 2017 Sep 15.
[Is] ISSN:1873-4235
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Supported binary liposome mixture of cationic liposome N-[1-(2,3-Dioleoyloxy)propyl]-N,N,N-trimethylammonium propane (DOTAP) and the zwitterionic liposome 1,2-Dioleoyl-sn-Glycero-3-Phosphoethanolamine (DOPE) were tethered on thiol monolayers in the absence and presence of gold nanoparticle to enhance sensor stability and sensitivity for label free DNA and protein sensing for the first time. Cysteamine hydrochloride (Cyst), 3-Mercaptopropionic acid (MPA), 11-Mercaptoundecanoic acid (MUDA) and 11-amino-1-undecane thiol (AUT) monolayers were used as tethers on gold surfaces. Electrochemical studies in the presence of [Fe(CN) ] indicate that the presence of both DOPE and AuNP decreases the electrostatic interaction between DOTAP and MPA layer during the formation of DOPE-DOTAP-AuNP (DDA) whereas they enhance the repulsive force on the Cyst and AUT monolayers. In the thiol monolayer supported DDA, the gelation of neutral lipid DOPE by the AuNP is disfavored which inturn promotes stability of vesicle structure. The membrane protein melittin's interaction with the DDA indicates the presence of intact vesicle by showing decreased charge transfer for the MUDA and AUT in the presence of [Fe(CN) ] . On the contrary, the presence of the bilayer and semi circled DDA on the MPA and cysteamine layers were confirmed by the increased redox reaction. Atomic Force Microscopic (AFM) and Transmission Electron Microscopic (TEM) images support the presence of an array like semi circled DDA on the MPA and well separated DDA vesicles on the MUDA with variable sizes. Dynamic Light Scattering (DLS) and Fourier Transform Infrared spectroscopy (FTIR) suggest effective coordination between DOPE, DOTAP and AuNP. Label free DNA hybridization sensing in presence of the negatively charged [Fe(CN) ] indicates the lowest DNA detection limit of 1×10 M with linearity range 1×10 to 1×10 M. Similarly, streptavidin sensing shows the lowest detection of 1ngml with a linear range 100ng to 1µg due to the increased reactive sites and distance.
[Mh] Termos MeSH primário: Técnicas Biossensoriais
Ácidos Nucleicos Livres/isolamento & purificação
Lipossomos/química
Proteínas/isolamento & purificação
[Mh] Termos MeSH secundário: Ácido 3-Mercaptopropiônico
Ácidos Nucleicos Livres/química
Cisteamina/química
Ácidos Graxos Monoinsaturados/química
Ouro/química
Limite de Detecção
Lipídeos/química
Nanopartículas Metálicas/química
Microscopia de Força Atômica
Microscopia Eletrônica de Transmissão
Hibridização de Ácido Nucleico
Fosfatidiletanolaminas/química
Compostos de Amônio Quaternário/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cell-Free Nucleic Acids); 0 (Fatty Acids, Monounsaturated); 0 (Lipids); 0 (Liposomes); 0 (Phosphatidylethanolamines); 0 (Proteins); 0 (Quaternary Ammonium Compounds); 2462-63-7 (dioleoyl phosphatidylethanolamine); 5UX2SD1KE2 (Cysteamine); 7440-57-5 (Gold); B03TJ3QU9M (3-Mercaptopropionic Acid); MR86K0XRQP (1,2-dioleoyloxy-3-(trimethylammonium)propane)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180214
[Lr] Data última revisão:
180214
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170428
[St] Status:MEDLINE


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[PMID]:28747004
[Au] Autor:Chen X; Ok YS; Mohan D; Pittman CU; Dou X
[Ad] Endereço:College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, PR China.
[Ti] Título:The stability and removal of water-dispersed CdSe/CdS core-shell quantum dots from water.
[So] Source:Chemosphere;185:926-933, 2017 Oct.
[Is] ISSN:1879-1298
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The increasingly wide use of semiconductor nanocrystals inevitably leads to their release into aquatic environment. The aggregation behaviors of 3-mercaptopropionic acid-capped CdSe/CdS core-shell quantum dots (MPA-QDs) under various water chemistry conditions were examined and their removal using Fe and Al coagulants was evaluated. Cationic species rather than concentrations affected the stability of MPA-QDs. Adding 2 mM Ca led to a much larger ζ-potential decrease and particle size increase than adding 150 mM K at each tested solution pH. This indicated that complexation and depletion of surface-bound carboxyl groups by divalent Ca has a more pronounced effect than compression of the electrical double layer by high concentrations of monovalent K . The presence of humic acid increased the stability of MPA-QDs, which might increase negative surface charging via overcoating or bind to the surface of MPA-QDs. The nanoparticles exhibited similar aggregation kinetics patterns in tap water and seawater, but varying patterns in the lake water because of the co-existence of 2.3 mM total of Ca and Mg . MPA-QDs (5 mg L ) were readily coagulated by 2.4 mM Al or 1.2 mM Fe in tap water. Al and Fe can bind with carboxyl groups of the surface capping ligands, neutralize the negative charges on the surface of MPA-QDs and decrease the electrostatic repulsion forces to induce MPA-QDs aggregation. In addition, MPA-QDs could be bound with and wrapped into the flocs of hydrolysis products of coagulants. The results reported here could help broaden our understanding of the impacts and remediation of water-dispersed core-shell QD nanoparticles.
[Mh] Termos MeSH primário: Compostos de Cádmio/química
Pontos Quânticos/química
Poluentes Químicos da Água/química
Purificação da Água/métodos
[Mh] Termos MeSH secundário: Ácido 3-Mercaptopropiônico/química
Concentração de Íons de Hidrogênio
Ligantes
Nanopartículas
Tamanho da Partícula
Pontos Quânticos/análise
Água/química
Poluentes Químicos da Água/análise
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cadmium Compounds); 0 (Ligands); 0 (Water Pollutants, Chemical); 059QF0KO0R (Water); B03TJ3QU9M (3-Mercaptopropionic Acid)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:180110
[Lr] Data última revisão:
180110
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170728
[St] Status:MEDLINE


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[PMID]:28826737
[Au] Autor:Morrow WP; Sardar S; Thapa P; Hossain MS; Foss FW; Pierce BS
[Ad] Endereço:Department of Chemistry & Biochemistry, College of Science, The University of Texas at Arlington, Arlington, TX 76019, United States.
[Ti] Título:Thiol dioxygenase turnover yields benzothiazole products from 2-mercaptoaniline and O -dependent oxidation of primary alcohols.
[So] Source:Arch Biochem Biophys;631:66-74, 2017 Oct 01.
[Is] ISSN:1096-0384
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Thiol dioxygenases are non-heme mononuclear iron enzymes that catalyze the O -dependent oxidation of free thiols (-SH) to produce the corresponding sulfinic acid (-SO ). Previous chemical rescue studies identified a putative Fe -O intermediate that precedes substrate oxidation in Mus musculus cysteine dioxygenase (Mm CDO). Given that a similar reactive intermediate has been identified in the extradiol dioxygenase 2, 3-HCPD, it is conceivable that these enzymes share other mechanistic features with regard to substrate oxidation. To explore this possibility, enzymatic reactions with Mm CDO (as well as the bacterial 3-mercaptopropionic acid dioxygenase, Av MDO) were performed using a substrate analogue (2-mercaptoaniline, 2ma). This aromatic thiol closely approximates the catecholic substrate of homoprotocatechuate of 2, 3-HPCD while maintaining the 2-carbon thiol-amine separation preferred by Mm CDO. Remarkably, both enzymes exhibit 2ma-gated O -consumption; however, none of the expected products for thiol dioxygenase or intra/extradiol dioxygenase reactions were observed. Instead, benzothiazoles are produced by the condensation of 2ma with aldehydes formed by an off-pathway oxidation of primary alcohols added to aqueous reactions to solubilize the substrate. The observed oxidation of 1º-alcohols in 2ma-reactions is consistent with the formation of a high-valent intermediate similar to what has been reported for cytochrome P450 and mononuclear iron model complexes.
[Mh] Termos MeSH primário: Ácido 3-Mercaptopropiônico/metabolismo
Álcoois/metabolismo
Compostos de Anilina/metabolismo
Azotobacter vinelandii/enzimologia
Benzotiazóis/metabolismo
Cisteína Dioxigenase/metabolismo
Dioxigenases/metabolismo
[Mh] Termos MeSH secundário: Animais
Azotobacter vinelandii/metabolismo
Camundongos
Modelos Moleculares
Oxirredução
Oxigênio/metabolismo
Especificidade por Substrato
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Alcohols); 0 (Aniline Compounds); 0 (Benzothiazoles); 137-07-5 (2-aminothiophenol); B03TJ3QU9M (3-Mercaptopropionic Acid); EC 1.13.11.- (Dioxygenases); EC 1.13.11.20 (Cysteine Dioxygenase); S88TT14065 (Oxygen)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170928
[Lr] Data última revisão:
170928
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170823
[St] Status:MEDLINE


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[PMID]:28672691
[Au] Autor:Xiang X; Wu C; Zhang BR; Gao T; Zhao J; Ma L; Jiang FL; Liu Y
[Ad] Endereço:State Key Laboratory of Virology & Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, PR China.
[Ti] Título:The relationship between the length of surface ligand and effects of CdTe quantum dots on the physiological functions of isolated mitochondria.
[So] Source:Chemosphere;184:1108-1116, 2017 Oct.
[Is] ISSN:1879-1298
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The potential toxicity of Quantum dots (QDs) should be assessed comprehensively for their fast spreading applications. Many studies have shown the toxicity of QDs is associated with their surface ligands. In this work, two analog ligands with one carbon difference, 2-mercaptoacetic acid (TGA) and 3-mercaptopropionic acid (MPA) were used as coating materials in the syntheses of two types of CdTe QDs with similar physicochemical properties. Then the biological effects of QDs on isolated mitochondria were studied. It was found that the two types of QDs could impair mitochondrial respiration and induce mitochondrial permeability transition (MPT). However, as compared with TGA-CdTe QDs, MPA-CdTe QDs had a stronger effect on MPT. The weaker effect of TGA-CdTe QDs on MPT might be owing to their better stability and thus less amount of released Cd , which could be further explained by the stronger affinity between the ligand (TGA) and the cadmium complexes in the crystal growth of QDs. These results highlighted the importance of ligands responsible for the toxicity of QDs at the sub-cellular level.
[Mh] Termos MeSH primário: Compostos de Cádmio/química
Mitocôndrias/fisiologia
Pontos Quânticos/química
[Mh] Termos MeSH secundário: Ácido 3-Mercaptopropiônico
Ligantes
Telúrio
Tioglicolatos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cadmium Compounds); 0 (Ligands); 0 (Thioglycolates); 7857H94KHM (2-mercaptoacetate); B03TJ3QU9M (3-Mercaptopropionic Acid); NQA0O090ZJ (Tellurium)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171005
[Lr] Data última revisão:
171005
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170705
[St] Status:MEDLINE


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[PMID]:28435258
[Au] Autor:Yin H; Fontana JM; Solandt J; Jussi JI; Xu H; Brismar H; Fu Y
[Ad] Endereço:Section of Cellular Biophysics, Department of Applied Physics, Royal Institute of Technology (KTH), Science for Life Laboratory, Solna.
[Ti] Título:Quantum dots modulate intracellular Ca level in lung epithelial cells.
[So] Source:Int J Nanomedicine;12:2781-2792, 2017.
[Is] ISSN:1178-2013
[Cp] País de publicação:New Zealand
[La] Idioma:eng
[Ab] Resumo:While adverse effects of nanoparticles on lung health have previously been proposed, few studies have addressed the direct effects of nanoparticle exposure on the airway epithelium. In this work, we examine the response of the pulmonary airway to nanoparticles by measuring intracellular Ca concentration ([Ca ] ) in the Calu-3 epithelial layer stimulated by 3-mercaptopropionic-acid (3MPA) coated CdSe-CdS/ZnS core-multishell quantum dots (QDs). Simultaneous transient transepithelial electrical resistance (TEER) decrease and global [Ca ] increase in Calu-3 epithelial layer, accompanied by cell displacements, contraction, and expansion, were observed under QD deposition. This suggests that a QD-induced global [Ca ] increase in the Calu-3 epithelial layer caused the transient TEER decrease. The [Ca ] increase was marked and rapid in the apical region, while [Ca ] decreased in the basolateral region of the epithelial layer. TEER transient response and extracellular Ca entry induced by QD deposition were completely inhibited in cells treated with stretched-activated (SA) inhibitor GdCl and store-operated calcium entry (SOCE) inhibitor BTP2 and in cells immersed in Ca -free medium. The voltage-gated calcium channel (VGCC) inhibitor nifedipine decreased, stabilized, and suppressed the TEER response, but did not affect the [Ca ] increase, due to QD deposition. This demonstrates that the Ca influx activated by QDs' mechanical stretch occurs through activation of both SA and SOCE channels. QD-induced [Ca ] increase occurred in the Calu-3 epithelial layer after culturing for 15 days, while significant TEER drop only occurred after 23 days. This work provides a new perspective from which to study direct interactions between airway epithelium and nanoparticles and may help to reveal the pathologies of pulmonary disease.
[Mh] Termos MeSH primário: Cálcio/metabolismo
Células Epiteliais/efeitos dos fármacos
Pulmão/citologia
Nanopartículas/toxicidade
Pontos Quânticos/toxicidade
[Mh] Termos MeSH secundário: Ácido 3-Mercaptopropiônico/farmacologia
Compostos de Cádmio/química
Compostos de Cádmio/toxicidade
Linhagem Celular
Células Epiteliais/fisiologia
Seres Humanos
Pulmão/efeitos dos fármacos
Nanopartículas/administração & dosagem
Pontos Quânticos/administração & dosagem
Compostos de Selênio/química
Compostos de Selênio/toxicidade
Sulfetos/química
Sulfetos/toxicidade
Compostos de Zinco/química
Compostos de Zinco/toxicidade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cadmium Compounds); 0 (Selenium Compounds); 0 (Sulfides); 0 (Zinc Compounds); A7F646JC5C (cadmium selenide); B03TJ3QU9M (3-Mercaptopropionic Acid); KPS085631O (zinc sulfide); SY7Q814VUP (Calcium)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170807
[Lr] Data última revisão:
170807
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170425
[St] Status:MEDLINE
[do] DOI:10.2147/IJN.S130136


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[PMID]:28211065
[Au] Autor:Zeng J; Liu S; Wang M; Yao S; Chen Y
[Ad] Endereço:State Key Laboratory of Chemo/Biosensing & Chemometrics, College of Chemistry & Chemical Engineering, Hunan University, Changsha, P. R. China.
[Ti] Título:The synthesis of weak acidic type hybrid monolith via thiol-ene click chemistry and its application in hydrophilic interaction chromatography.
[So] Source:Electrophoresis;38(9-10):1325-1333, 2017 05.
[Is] ISSN:1522-2683
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:In this work, a porous structure and good permeability monolithic column was polymerized in UV transparent fused-silica capillaries via photo-initiated thiol-ene click polymerization of 2,4,6,8-tetravinyl-2,4,6,8-tetramethylcyclotetrasiloxane (TMTVS), pentaerythritol tetra(3-mercaptopropionate)(PETMP), itaconic acid, respectively, in the presence of porogenic solvents (tetrahydrofuranand methanol) and an initiator (2,2-dimethoxy-2-phenylacetophenone) (DMPA) within 30 min. The physical properties of this monolith were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy and nitrogen adsorption/desorption measurements. For an overall evaluation of the monolith in chromatographic application, separations of polycyclic aromatic hydrocarbons (PAHs), phenols, amides and bases were carried out. The column efficiency of this monolith could be as high as 112 560 N/m. It also possesses a potential application in fabrication of monoliths with high efficiency for c-LC. In addition, the resulting monolithic column demonstrated the potential use in analysis of environment waters.
[Mh] Termos MeSH primário: Ácido 3-Mercaptopropiônico/análogos & derivados
Cromatografia Líquida/métodos
Química Click/métodos
Compostos Heterocíclicos/química
Propilenoglicóis/química
Siloxanas/química
Succinatos/química
Compostos de Sulfidrila/química
[Mh] Termos MeSH secundário: Ácido 3-Mercaptopropiônico/química
Acetonitrilos
Amidas/análise
Amidas/isolamento & purificação
Interações Hidrofóbicas e Hidrofílicas
Modelos Químicos
Fenóis/análise
Fenóis/isolamento & purificação
Hidrocarbonetos Aromáticos Policíclicos/análise
Hidrocarbonetos Aromáticos Policíclicos/isolamento & purificação
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Acetonitriles); 0 (Amides); 0 (Heterocyclic Compounds); 0 (Phenols); 0 (Polycyclic Aromatic Hydrocarbons); 0 (Propylene Glycols); 0 (Siloxanes); 0 (Succinates); 0 (Sulfhydryl Compounds); 0 (pentaerythritol tetra(3-mercaptopropionate)); 0 (tetravinyl-tetramethylcyclo-tetrasiloxane); B03TJ3QU9M (3-Mercaptopropionic Acid); Q4516562YH (itaconic acid); Z072SB282N (acetonitrile)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171106
[Lr] Data última revisão:
171106
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170218
[St] Status:MEDLINE
[do] DOI:10.1002/elps.201600526


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[PMID]:28006684
[Au] Autor:Jin M; Mou ZL; Zhang RL; Liang SS; Zhang ZQ
[Ad] Endereço:Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, Key Laboratory of Medicinal Resource and Natural Pharmaceutical Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an 710062, China.
[Ti] Título:An efficient ratiometric fluorescence sensor based on metal-organic frameworks and quantum dots for highly selective detection of 6-mercaptopurine.
[So] Source:Biosens Bioelectron;91:162-168, 2017 May 15.
[Is] ISSN:1873-4235
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The development of a simple and accurate quantitative method for the determination of 6-mercaptopurine (6-MP) is of great importance because of its serious side effects. Ratiometric fluorescence (RF) sensors are not subject to interference from environmental factors, and exhibit enhanced precision and accuracy. Therefore, a novel RF sensor for the selective detection of 6-MP was developed based on a dual-emission nanosensor. The nanosensor was fabricated by combining a blue-emission metal-organic framework (MOF) NH -MIL-53(Al) (λ =425nm) with green-emission 3-mercaptopropionic acid-capped CdTe quantum dots (MPA-CdTe QDs) (λ =528nm) under a single excitation wavelength (335nm). Upon addition of 6-MP, the fluorescence of NH -MIL-53(Al) in the nanohybrid was selectively quenched due to strong inner filter effects, while the fluorescence of the MPA-CdTe QDs was enhanced. The novel RF sensor exhibited higher selectivity towards 6-MP than CdTe QDs alone, and higher sensitivity than MOFs alone. 6-MP could be detected in the range of 0-50µM with a detection limit of 0.15µM (S/N=3). The developed sensor was applied for the determination of 6-MP in human urine samples and satisfactory results were obtained. Overall, a novel and efficient fluorescence-based method was developed for the detection of 6-MP in biosamples.
[Mh] Termos MeSH primário: Compostos de Cádmio/química
Corantes Fluorescentes/química
Mercaptopurina/urina
Compostos Organometálicos/química
Pontos Quânticos/química
Espectrometria de Fluorescência/métodos
Telúrio/química
[Mh] Termos MeSH secundário: Ácido 3-Mercaptopropiônico/química
Técnicas Biossensoriais/métodos
Seres Humanos
Limite de Detecção
Pontos Quânticos/ultraestrutura
[Pt] Tipo de publicação:EVALUATION STUDIES; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cadmium Compounds); 0 (Fluorescent Dyes); 0 (Organometallic Compounds); B03TJ3QU9M (3-Mercaptopropionic Acid); E7WED276I5 (Mercaptopurine); NQA0O090ZJ (Tellurium); STG188WO13 (cadmium telluride)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161223
[St] Status:MEDLINE


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[PMID]:28853269
[Au] Autor:Li N; Li M; Yu Z; Zhou J; Huang J
[Ad] Endereço:Zhejiang Hisun Pharmaceutical Co. Ltd., Taizhou 318000, Zhejiang, China.
[Ti] Título:[One-step fermentation for producing simvastatin via RNAi silencing of lovF gene in Aspergillus terreus].
[So] Source:Sheng Wu Gong Cheng Xue Bao;32(4):478-486, 2016 Apr 25.
[Is] ISSN:1000-3061
[Cp] País de publicação:China
[La] Idioma:chi
[Ab] Resumo:Simvastatin is one of the important prescription drugs for hypercholesterolemia. Monacolin J is a key intermediate during simvastatin synthesis, and also an intermediate of lovastatin biosynthesis. In this work, we construct a monacolin J producing strain via RNA interference to achieve one-step fermentation to obtain simvastatin. The lovF gene silencing plasmid pMHJ137 was constructed and transformed into Aspergillus terreus by Agrobacterium tumefaciens mediated transformation method. Precursor DMB-S-MMP was supplied during the fermentation to screen positive strains of transformants; which also further confirmed the simvastatin producing capability of MJ1-24 by one-step fermentation. Strain MJ1-24 produced monacolin J rather than lovastatin, and the feeding of DMB-S-MMP resulted in the generation of simvastatin. This study suggested that RNAi can efficiently silence the lovF gene of A. terreus and promote the simvastatin production by one-step fermentation.
[Mh] Termos MeSH primário: Aspergillus/genética
Fermentação
Interferência de RNA
Sinvastatina/química
[Mh] Termos MeSH secundário: Ácido 3-Mercaptopropiônico/análogos & derivados
Aspergillus/química
Microbiologia Industrial
Naftalenos/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Naphthalenes); 0 (dimethylbutyryl-S-methyl mercaptopropionate); AGG2FN16EV (Simvastatin); B03TJ3QU9M (3-Mercaptopropionic Acid); P5IQ0SI56N (monacolin J)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171002
[Lr] Data última revisão:
171002
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170831
[St] Status:MEDLINE
[do] DOI:10.13345/j.cjb.150344


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[PMID]:27632073
[Au] Autor:Besharat Z; Wakeham D; Johnson CM; Luengo GS; Greaves A; Odnevall Wallinder I; Göthelid M; Rutland MW
[Ad] Endereço:KTH Royal Institute of Technology, Department of Chemistry, Division of Surface and Corrosion Science, Stockholm SE-100 44, Sweden; KTH Royal Institute of Technology, Department of Material Physics, MNF, ICT, Stockholm SE-164 40, Sweden.
[Ti] Título:Mixed monolayers of alkane thiols with polar terminal group on gold: Investigation of structure dependent surface properties.
[So] Source:J Colloid Interface Sci;484:279-290, 2016 Dec 15.
[Is] ISSN:1095-7103
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Adsorption of thiols with cationic or anionic terminal group on gold has been studied from mixed solutions of 11-Amino-1-undecanethiol (AUT) and 3-Mercaptopropionic acid (MPA) using Quartz Crystal Microbalance with Dissipation (QCM-D), X-ray Photoelectron Spectroscopy (XPS), atomic force microscopy (AFM) and contact angles. The goal is to probe the nature of such layers, and the additivity or otherwise of the pH responsiveness, with a view to evaluate their suitability as smart materials. For each of the two pure (unmixed) cases, ordered molecular monolayers are formed with sulfur binding to gold and the alkane chain pointing out from the surface as expected. Adsorption from the thiol mixtures, however, leads to a more complex behaviour. The surface concentration of thiols from the mixtures, as determined by QCM-D, is considerably lower than for the pure cases and it reaches a minimum at a 3:1 MPA/AUT relative concentration in the solution. The XPS results confirm a reduction in adsorbed amount in mixtures with the lowest overall intensity for the 3:1 ratio. Monolayers formed from mixtures display a wettability which is much lower and less pH sensitive. Collectively these results confirm that for adsorption from mixed systems, the configuration is completely different. Complex formation in the mixed solutions leads to the adsorption of molecules parallel to the surface in an axially in-plane configuration. This parallel layer of thiols is mechanically relatively robust to nano-shaving based on AFM measurements. These results will have a significant impact on the design of biomimetic surface coatings particularly when mixtures of oppositely charged molecules are present on the surface, as is commonly the case in biological, proteinaceous surfaces (e.g. hair and skin).
[Mh] Termos MeSH primário: Ácido 3-Mercaptopropiônico/química
Alcanos/química
Ouro/química
Compostos de Sulfidrila/química
Enxofre/química
[Mh] Termos MeSH secundário: Adsorção
Concentração de Íons de Hidrogênio
Espectroscopia Fotoeletrônica
Técnicas de Microbalança de Cristal de Quartzo
Eletricidade Estática
Tensão Superficial
Termodinâmica
Molhabilidade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (11-amino-1-undecanethiol); 0 (Alkanes); 0 (Sulfhydryl Compounds); 70FD1KFU70 (Sulfur); 7440-57-5 (Gold); B03TJ3QU9M (3-Mercaptopropionic Acid)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:171008
[Lr] Data última revisão:
171008
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160916
[St] Status:MEDLINE



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