Base de dados : MEDLINE
Pesquisa : D12.125.072.050 [Categoria DeCS]
Referências encontradas : 763 [refinar]
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[PMID]:28684415
[Au] Autor:Bakou M; Hille K; Kracklauer M; Spanopoulou A; Frost CV; Malideli E; Yan LM; Caporale A; Zacharias M; Kapurniotu A
[Ad] Endereço:From the Division of Peptide Biochemistry, Technische Universität München, D-85354 Freising, Germany and.
[Ti] Título:Key aromatic/hydrophobic amino acids controlling a cross-amyloid peptide interaction amyloid self-assembly.
[So] Source:J Biol Chem;292(35):14587-14602, 2017 Sep 01.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The interaction of the intrinsically disordered polypeptide islet amyloid polypeptide (IAPP), which is associated with type 2 diabetes (T2D), with the Alzheimer's disease amyloid-ß (Aß) peptide modulates their self-assembly into amyloid fibrils and may link the pathogeneses of these two cell-degenerative diseases. However, the molecular determinants of this interaction remain elusive. Using a systematic alanine scan approach, fluorescence spectroscopy, and other biophysical methods, including heterocomplex pulldown assays, far-UV CD spectroscopy, the thioflavin T binding assay, transmission EM, and molecular dynamics simulations, here we identified single aromatic/hydrophobic residues within the amyloid core IAPP region as hot spots or key residues of its cross-interaction with Aß40(42) peptide. Importantly, we also find that none of these residues in isolation plays a key role in IAPP self-assembly, whereas simultaneous substitution of four aromatic/hydrophobic residues with Ala dramatically impairs both IAPP self-assembly and hetero-assembly with Aß40(42). Furthermore, our experiments yielded several novel IAPP analogs, whose sequences are highly similar to that of IAPP but have distinct amyloid self- or cross-interaction potentials. The identified similarities and major differences controlling IAPP cross-peptide interaction with Aß40(42) its amyloid self-assembly offer a molecular basis for understanding the underlying mechanisms. We propose that these insights will aid in designing intervention strategies and novel IAPP analogs for the management of type 2 diabetes, Alzheimer's disease, or other diseases related to IAPP dysfunction or cross-amyloid interactions.
[Mh] Termos MeSH primário: Aminoácidos/metabolismo
Peptídeos beta-Amiloides/metabolismo
Polipeptídeo Amiloide das Ilhotas Pancreáticas/metabolismo
Modelos Moleculares
Fragmentos de Peptídeos/metabolismo
Agregação Patológica de Proteínas/metabolismo
[Mh] Termos MeSH secundário: Substituição de Aminoácidos
Aminoácidos/química
Aminoácidos Aromáticos
Peptídeos beta-Amiloides/síntese química
Peptídeos beta-Amiloides/química
Dicroísmo Circular
Seres Humanos
Interações Hidrofóbicas e Hidrofílicas
Polipeptídeo Amiloide das Ilhotas Pancreáticas/síntese química
Polipeptídeo Amiloide das Ilhotas Pancreáticas/química
Cinética
Metilação
Microscopia Eletrônica de Transmissão
Simulação de Dinâmica Molecular
Fragmentos de Peptídeos/síntese química
Fragmentos de Peptídeos/química
Estabilidade Proteica
Estrutura Secundária de Proteína
Técnicas de Síntese em Fase Sólida
Solubilidade
Espectrometria de Fluorescência
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids); 0 (Amino Acids, Aromatic); 0 (Amyloid beta-Peptides); 0 (Islet Amyloid Polypeptide); 0 (Peptide Fragments); 0 (amyloid beta-protein (1-40)); 0 (amyloid beta-protein (1-42))
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170926
[Lr] Data última revisão:
170926
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170708
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.M117.774893


  2 / 763 MEDLINE  
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[PMID]:28570934
[Au] Autor:Li WK; Zhang HX; Shi YP
[Ad] Endereço:CAS Key Laboratory of Chemistry of Northwestern Plant Resources and Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, PR China; University of Chinese Academy of Sciences, Beijing 100039, PR China.
[Ti] Título:Selective determination of aromatic amino acids by magnetic hydroxylated MWCNTs and MOFs based composite.
[So] Source:J Chromatogr B Analyt Technol Biomed Life Sci;1059:27-34, 2017 Aug 01.
[Is] ISSN:1873-376X
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:A novel magnetic solid-phase extraction (MSPE) based method was established for aromatic amino acids (AAAs) selective determination. Central to the method was the adopted extractant. An explored composite of metal organic frameworks (MOFs) and magnetic carbon nanotubes (CNTs) was employed for that, which exhibited superior adsorption affinity and selectivity to AAAs as compared to other amino acids with the mechanisms attributed to multiple hydrogen bonding and π-π electron-donor-acceptor (EDA) interactions. The morphology, structure and magnetic behavior of the composite were characterized and related MSPE procedure was established. Critical extraction conditions including pH, extraction time, temperature and salt addition were investigated and optimized. Subsequently the concentrations of three AAAs tryptophan (Trp), tyrosine (Tyr) and phenylalanine (Phe) in Lanzhou lily were determined by the composite based MSPE procedure coupled with high performance liquid chromatography-ultraviolet detection (HPLC-UV). The composite provided a superior sample clean-up function and many of the matrix interferences were eliminated, thus ensured AAAs were accurately and efficiently determined. The results showed that the method had good linearities with the linear coefficients above 0.99, desirable recoveries ranged from 88.0% to 96.8% with the RSD less than 5.1%, satisfactory precision and low limits of detection (LODs) which were respectively 0.04, 0.11, and 0.87ng/g for Trp, Tyr and Phe. The composite based MSPE-HPLC-UV method has great potentials for the AAAs selective determination from complex matrix samples.
[Mh] Termos MeSH primário: Aminoácidos Aromáticos/análise
Nanocompostos/química
Nanotubos de Carbono/química
Extração em Fase Sólida/métodos
[Mh] Termos MeSH secundário: Adsorção
Aminoácidos Aromáticos/isolamento & purificação
Cromatografia Líquida de Alta Pressão
Óxido Ferroso-Férrico
Concentração de Íons de Hidrogênio
Fenômenos Magnéticos
Sais
Temperatura Ambiente
Fatores de Tempo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids, Aromatic); 0 (Nanotubes, Carbon); 0 (Salts); XM0M87F357 (Ferrosoferric Oxide)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170623
[Lr] Data última revisão:
170623
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170602
[St] Status:MEDLINE


  3 / 763 MEDLINE  
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[PMID]:28570676
[Au] Autor:Hong M; Jung J; Park HS; Lee SM; Jeong NJ; Kim SH; Lee KW; Lee JA; Kim MS
[Ad] Endereço:Division of Metabolism and Nutrition, Korea Food Research Institute, Gyeonggi-do, Republic of Korea.
[Ti] Título:Shaofu Zhuyu decoction ameliorates obesity-mediated hepatic steatosis and systemic inflammation by regulating metabolic pathways.
[So] Source:PLoS One;12(6):e0178514, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Shaofu Zhuyu decoction (SFZYD, also known as Sobokchugeo-tang), a classical prescription drug in traditional East Asian medicine, has been used to treat blood stasis syndrome (BSS). Hepatic steatosis is the result of excess caloric intake, and its pathogenesis involves internal retention of phlegm and dampness, blood stasis, and liver Qi stagnation. To evaluate the effects of treatment with SFZYD on obesity-induced inflammation and hepatic steatosis, we fed male C57BL/6N mice a high fat diet (HFD) for 8 weeks and then treated them with SFZYD by oral gavage for an additional 4 weeks. The results of histological and biochemical examinations indicated that SFZYD treatment ameliorates systemic inflammation and hepatic steatosis. A partial least squares-discriminant analysis (PLS-DA) scores plot of serum metabolites showed that HFD mice began to produce metabolites similar to those of normal chow (NC) mice after SFZYD administration. We noted significant alterations in the levels of twenty-seven metabolites, alterations indicating that SFZYD regulates the TCA cycle, the pentose phosphate pathway and aromatic amino acid metabolism. Increases in the levels of TCA cycle intermediate metabolites, such as 2-oxoglutaric acid, isocitric acid, and malic acid, in the serum of obese mice were significantly reversed after SFZYD treatment. In addition to inducing changes in the above metabolites, treatment with SFZYD also recovered the expression of genes related to hepatic mitochondrial dysfunction, including Ucp2, Cpt1α, and Ppargc1α, as well as the expression of genes involved in lipid metabolism and inflammation, without affecting glucose uptake or insulin signaling. Taken together, these findings suggest that treatment with SFZYD ameliorated obesity-induced systemic inflammation and hepatic steatosis by regulating inflammatory cytokine and adipokine levels in the circulation and various tissues. Moreover, treatment with SFZYD also reversed alterations in the levels of metabolites of the TCA cycle, the pentose phosphate pathway and aromatic amino acid metabolism.
[Mh] Termos MeSH primário: Medicamentos de Ervas Chinesas
Fígado Gorduroso/prevenção & controle
Inflamação/prevenção & controle
Obesidade/complicações
[Mh] Termos MeSH secundário: Aminoácidos Aromáticos/metabolismo
Animais
Cromatografia Líquida de Alta Pressão
Fígado Gorduroso/tratamento farmacológico
Fígado Gorduroso/etiologia
Inflamação/tratamento farmacológico
Masculino
Camundongos
Camundongos Endogâmicos C57BL
Reação em Cadeia da Polimerase em Tempo Real
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids, Aromatic); 0 (Drugs, Chinese Herbal); 0 (Shao-Fu-Zhu-Yu)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170926
[Lr] Data última revisão:
170926
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170602
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0178514


  4 / 763 MEDLINE  
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[PMID]:28475645
[Au] Autor:Yang JK; Xiong W; Chen FY; Xu L; Han ZG
[Ad] Endereço:College of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan, China.
[Ti] Título:Aromatic amino acids in the cellulose binding domain of Penicillium crustosum endoglucanase EGL1 differentially contribute to the cellulose affinity of the enzyme.
[So] Source:PLoS One;12(5):e0176444, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The cellulose binding domain (CBD) of cellulase binding to cellulosic materials is the initiation of a synergistic action on the enzymatic hydrolysis of the most abundant renewable biomass resources in nature. The binding of the CBD domain to cellulosic substrates generally relies on the interaction between the aromatic amino acids structurally located on the flat face of the CBD domain and the glucose rings of cellulose. In this study, we found the CBD domain of a newly cloned Penicillium crustosum endoglucanase EGL1, which was phylogenetically related to Aspergillus, Fusarium and Rhizopus, and divergent from the well-characterized Trichoderma reeseis cellulase CBD domain, contain two conserved aromatic amino acid-rich regions, Y451-Y452 and Y477-Y478-Y479, among which three amino acids Y451, Y477, and Y478 structurally sited on a flat face of this domain. Cellulose binding assays with green fluorescence protein as the marker, adsorption isotherm assays and an isothermal titration calorimetry assays revealed that although these three amino acids participated in this process, the Y451-Y452 appears to contribute more to the cellulose binding than Y477-Y478-Y479. Further glycine scanning mutagenesis and structural modelling revealed that the binding between CBD domain and cellulosic materials might be multi-amino-acids that participated in this process. The flexible poly-glucose molecule could contact Y451, Y477, and Y478 which form the contacting flat face of CBD domain as the typical model, some other amino acids in or outside the flat face might also participate in the interaction. Thus, it is possible that the conserved Y451-Y452 of CBD might have a higher chance of contacting the cellulosic substrates, contributing more to the affinity of CBD than the other amino acids.
[Mh] Termos MeSH primário: Aminoácidos Aromáticos/metabolismo
Celulase/metabolismo
Celulose/metabolismo
[Mh] Termos MeSH secundário: Calorimetria
Celulase/genética
Proteínas de Fluorescência Verde/genética
Especificidade por Substrato
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids, Aromatic); 0 (enhanced green fluorescent protein); 147336-22-9 (Green Fluorescent Proteins); 9004-34-6 (Cellulose); EC 3.2.1.4 (Cellulase); EC 3.2.1.4 (endoglucanase EGL1)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170915
[Lr] Data última revisão:
170915
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170506
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0176444


  5 / 763 MEDLINE  
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[PMID]:28288194
[Au] Autor:Wang ZT; Verma SK; Dubey JP; Sibley LD
[Ad] Endereço:Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, United States of America.
[Ti] Título:The aromatic amino acid hydroxylase genes AAH1 and AAH2 in Toxoplasma gondii contribute to transmission in the cat.
[So] Source:PLoS Pathog;13(3):e1006272, 2017 Mar.
[Is] ISSN:1553-7374
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The Toxoplasma gondii genome contains two aromatic amino acid hydroxylase genes, AAH1 and AAH2 encode proteins that produce L-DOPA, which can serve as a precursor of catecholamine neurotransmitters. It has been suggested that this pathway elevates host dopamine levels thus making infected rodents less fearful of their definitive Felidae hosts. However, L-DOPA is also a structural precursor of melanins, secondary quinones, and dityrosine protein crosslinks, which are produced by many species. For example, dityrosine crosslinks are abundant in the oocyst walls of Eimeria and T. gondii, although their structural role has not been demonstrated, Here, we investigated the biology of AAH knockout parasites in the sexual reproductive cycle within cats. We found that ablation of the AAH genes resulted in reduced infection in the cat, lower oocyst yields, and decreased rates of sporulation. Our findings suggest that the AAH genes play a predominant role during infection in the gut of the definitive feline host.
[Mh] Termos MeSH primário: Genes de Protozoários/fisiologia
Oxigenases de Função Mista/metabolismo
Toxoplasmose Animal/transmissão
[Mh] Termos MeSH secundário: Aminoácidos Aromáticos
Animais
Gatos
Camundongos
Microscopia de Fluorescência
Oocistos/parasitologia
Organismos Geneticamente Modificados
Toxoplasma/enzimologia
Toxoplasma/genética
Toxoplasma/crescimento & desenvolvimento
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids, Aromatic); EC 1.- (Mixed Function Oxygenases)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:171112
[Lr] Data última revisão:
171112
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170314
[St] Status:MEDLINE
[do] DOI:10.1371/journal.ppat.1006272


  6 / 763 MEDLINE  
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[PMID]:28257757
[Au] Autor:Marino ND; Boothroyd JC
[Ad] Endereço:Department of Microbiology and Immunology, Stanford University School of Medicine, CA 94305, USA.
[Ti] Título:Toxoplasma growth in vitro is dependent on exogenous tyrosine and is independent of AAH2 even in tyrosine-limiting conditions.
[So] Source:Exp Parasitol;176:52-58, 2017 May.
[Is] ISSN:1090-2449
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Toxoplasma gondii is an obligate intracellular parasite capable of infecting virtually all nucleated cell types in almost all warm-blooded animals. Interestingly, Toxoplasma has a relatively full repertoire of amino acid biosynthetic machinery, perhaps reflecting its broad host range and, consequently, its need to adapt to a wide array of amino acid resources. Although Toxoplasma has been shown to be auxotrophic for tryptophan and arginine, it has not previously been determined if Toxoplasma is also auxotrophic for tyrosine. Toxoplasma tachyzoites and bradyzoites were recently found to express an amino acid hydroxylase (AAH2) that is capable of synthesizing tyrosine and dihydroxyphenylalanine (DOPA) from phenylalanine; however, the role of AAH2 in tachyzoite and bradyzoite infection has not yet been identified. To determine if Toxoplasma requires exogenous tyrosine for growth, we performed growth assays on tachyzoites and bradyzoites in nutrient-rich media titrated with varying amounts of tyrosine. We found that Toxoplasma tachyzoites form significantly smaller plaques in tyrosine-limiting media in a dose-dependent manner and that this phenotype is not affected by deletion of TgAAH2. To determine if bradyzoites require exogenous tyrosine for growth, we induced differentiation from tachyzoites in vitro in tyrosine-limiting media and found that replication and vacuole number are all decreased in tyrosine-deficient media. Importantly, culture of confluent human fibroblasts in tyrosine-deficient media does not affect their viability, indicating that, at least in vitro, the need for tyrosine is at the level of Toxoplasma, not the host cell supporting its growth.
[Mh] Termos MeSH primário: Hidrolases/metabolismo
Toxoplasma/crescimento & desenvolvimento
Tirosina/metabolismo
[Mh] Termos MeSH secundário: Aminoácidos Aromáticos/metabolismo
Meios de Cultura
Relação Dose-Resposta a Droga
Fibroblastos/parasitologia
Fibroblastos/ultraestrutura
Seres Humanos
Hidrolases/genética
Inoculações Seriadas
Toxoplasma/efeitos dos fármacos
Toxoplasma/metabolismo
Tirosina/farmacologia
Vacúolos/efeitos dos fármacos
Vacúolos/parasitologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids, Aromatic); 0 (Culture Media); 42HK56048U (Tyrosine); EC 3.- (Hydrolases)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170510
[Lr] Data última revisão:
170510
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170305
[St] Status:MEDLINE


  7 / 763 MEDLINE  
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[PMID]:28126922
[Au] Autor:Rennella E; Sára T; Juen M; Wunderlich C; Imbert L; Solyom Z; Favier A; Ayala I; Weinhäupl K; Schanda P; Konrat R; Kreutz C; Brutscher B
[Ad] Endereço:Institut de Biologie Structurale, Université Grenoble 1, 71 avenue des Martyrs, 38044 Grenoble Cedex 9, France.
[Ti] Título:RNA binding and chaperone activity of the E. coli cold-shock protein CspA.
[So] Source:Nucleic Acids Res;45(7):4255-4268, 2017 Apr 20.
[Is] ISSN:1362-4962
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Ensuring the correct folding of RNA molecules in the cell is of major importance for a large variety of biological functions. Therefore, chaperone proteins that assist RNA in adopting their functionally active states are abundant in all living organisms. An important feature of RNA chaperone proteins is that they do not require an external energy source to perform their activity, and that they interact transiently and non-specifically with their RNA targets. So far, little is known about the mechanistic details of the RNA chaperone activity of these proteins. Prominent examples of RNA chaperones are bacterial cold shock proteins (Csp) that have been reported to bind single-stranded RNA and DNA. Here, we have used advanced NMR spectroscopy techniques to investigate at atomic resolution the RNA-melting activity of CspA, the major cold shock protein of Escherichia coli, upon binding to different RNA hairpins. Real-time NMR provides detailed information on the folding kinetics and folding pathways. Finally, comparison of wild-type CspA with single-point mutants and small peptides yields insights into the complementary roles of aromatic and positively charged amino-acid side chains for the RNA chaperone activity of the protein.
[Mh] Termos MeSH primário: Proteínas e Peptídeos de Choque Frio/química
Proteínas e Peptídeos de Choque Frio/metabolismo
Proteínas de Escherichia coli/química
Proteínas de Escherichia coli/metabolismo
Dobramento de RNA
RNA/química
[Mh] Termos MeSH secundário: Aminoácidos Aromáticos/química
Ressonância Magnética Nuclear Biomolecular
Conformação de Ácido Nucleico
Ligação Proteica
Conformação Proteica
RNA/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids, Aromatic); 0 (Cold Shock Proteins and Peptides); 0 (CspA protein, E coli); 0 (Escherichia coli Proteins); 63231-63-0 (RNA)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170825
[Lr] Data última revisão:
170825
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170128
[St] Status:MEDLINE
[do] DOI:10.1093/nar/gkx044


  8 / 763 MEDLINE  
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[PMID]:28024626
[Au] Autor:Singh P; Brar SK; Bajaj M; Narang N; Mithu VS; Katare OP; Wangoo N; Sharma RK
[Ad] Endereço:Centre for Nanoscience and Nanotechnology, Panjab University, Sector 14, Chandigarh 160014, India.
[Ti] Título:Self-assembly of aromatic α-amino acids into amyloid inspired nano/micro scaled architects.
[So] Source:Mater Sci Eng C Mater Biol Appl;72:590-600, 2017 Mar 01.
[Is] ISSN:1873-0191
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:In the pursuit for design of novel bio inspired materials, aromatic α-amino acids (phenylalanine, tyrosine, tryptophan and histidine) have been investigated for the generation of well-ordered self-assembled architects such as fibrils, rods, ribbons and twisted nanosheets in varying solvent systems. These nano/micro scaled architects were thoroughly characterized using FE-SEM, confocal microscopy, optical microscopy, H NMR, FTIR, XRD and TGA. These self-assembled architects were histologically stained with Congo red and thioflavin T dyes for investigation of amyloid morphology which revealed that the deposited state of ordered assemblies exhibit specific characteristic of amyloid deposits. The self-assembly of aromatic amino acids was observed to be driven by non-covalent forces such as π-π stacking, van der Waals and electrostatic interaction.
[Mh] Termos MeSH primário: Aminoácidos Aromáticos/química
Amiloide/química
[Mh] Termos MeSH secundário: Aminoácidos Aromáticos/metabolismo
Amiloide/metabolismo
Vermelho Congo/química
Vermelho Congo/metabolismo
Espectroscopia de Ressonância Magnética
Microscopia de Força Atômica
Microscopia Confocal
Nanoestruturas/química
Espectroscopia de Infravermelho com Transformada de Fourier
Termogravimetria
Tiazóis/química
Tiazóis/metabolismo
Água/química
Difração de Raios X
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids, Aromatic); 0 (Amyloid); 0 (Thiazoles); 059QF0KO0R (Water); 2390-54-7 (thioflavin T); 3U05FHG59S (Congo Red)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170420
[Lr] Data última revisão:
170420
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161228
[St] Status:MEDLINE


  9 / 763 MEDLINE  
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[PMID]:28024187
[Au] Autor:Basu Baul TS; Kehie P; Duthie A; Guchhait N; Raviprakash N; Mokhamatam RB; Manna SK; Armata N; Scopelliti M; Wang R; Englert U
[Ad] Endereço:Centre for Advanced Studies in Chemistry, North-Eastern Hill University, NEHU Permanent Campus, Umshing, Shillong 793 022, India. Electronic address: basubaul@nehu.ac.in.
[Ti] Título:Synthesis, photophysical properties and structures of organotin-Schiff bases utilizing aromatic amino acid from the chiral pool and evaluation of the biological perspective of a triphenyltin compound.
[So] Source:J Inorg Biochem;168:76-89, 2017 Mar.
[Is] ISSN:1873-3344
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Five new organotin(IV) complexes of compositions [Me SnL ] (1), [Me SnL ] (2), [Me SnL ] (3), [Ph SnL H] (4) and [Ph SnL H] (5) (where L =(2S)-2-((E)-((Z)-4-hydroxypent-3-en-2-ylidene)amino)-3-(1H-indol-3-yl)propanoate, L =(2S)-(E)-2-((2-hydroxybenzylidene)amino)-3-(1H-indol-3-yl)propanoate and L =(2S)-(E)-2-((1-(2-hydroxyphenyl)ethylidene)amino)-3-(1H-indol-3-yl)propanoate were synthesized and spectroscopically characterized. The crystal structures of 1-4 were determined. For the dimethyltin derivative 2, a polymeric chain structure was observed as a result of a long Sn∙∙∙O contact involving the exocyclic carbonyl oxygen-atom from the tridentate ligand of a neighboring Sn-complex unit. The tin atom in this complex has a distorted octahedral coordination geometry, in which the long Sn-O bond is almost trans to the tridentate ligand nitrogen-atom. In contrast, the dimethyltin(IV) complexes 1 and 3 displayed discrete monomeric structures where the tin atom has distorted trigonal-bipyramidal geometry with the two coordinating L oxygen atoms defining the axial positions. On the other hand, 4 is a chain polymer in the solid state. The ligand-bridged Sn atoms adopt a trans-Ph SnO trigonal-bipyramidal configuration with equatorial phenyl groups. A carboxylato oxygen atom from one and the hydroxyl oxygen of the successive ligand in the chain occupy the axial positions. The solution structures were predicted by the use of Sn NMR chemical shifts. The photophysical properties of the complexes were investigated in the solid and in solution. The triphenyltin(IV) compound 4 was tested in detail ex vivo against A375 (human melanoma) cell line, exhibiting an IC value of 261nM to induce cell death as assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay without significant alteration of cytolysis as determined by lactate dehydrogenase (LDH) assay. Compound 4-mediated potent cell death was also determined by Live and Dead assay and caspase-mediated cleavage of poly-ADP ribose polymerase (PARP). Potent cell death activity was not observed in primary cells, like blood-derived peripheral mononuclear cells (PBMC). Compound 4 inhibited the diphenyl hexatriene (DPH) binding to cells and decreased the micro viscosity in a dose-dependent manner. Additionally, the ability of 4 and cyclodextrin (CD) to interact was determined by molecular modelling.
[Mh] Termos MeSH primário: Aminoácidos Aromáticos/química
Compostos Orgânicos de Estanho/química
Compostos Orgânicos de Estanho/farmacologia
Processos Fotoquímicos
Bases de Schiff/química
[Mh] Termos MeSH secundário: Antineoplásicos/síntese química
Antineoplásicos/química
Antineoplásicos/farmacologia
Linhagem Celular Tumoral
Sobrevivência Celular/efeitos dos fármacos
Cristalografia por Raios X
Seres Humanos
Concentração Inibidora 50
Modelos Moleculares
Simulação de Acoplamento Molecular
Compostos Orgânicos de Estanho/síntese química
Bases de Schiff/síntese química
Bases de Schiff/farmacologia
Estereoisomerismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids, Aromatic); 0 (Antineoplastic Agents); 0 (Organotin Compounds); 0 (Schiff Bases); 95T92AGN0V (triphenyltin)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171113
[Lr] Data última revisão:
171113
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161227
[St] Status:MEDLINE


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[PMID]:27987768
[Au] Autor:Alex SA; Rajiv S; Chakravarty S; Chandrasekaran N; Mukherjee A
[Ad] Endereço:Centre for Nanobiotechnology, VIT University, Vellore, India.
[Ti] Título:Significance of surface functionalization of Gold Nanorods for reduced effect on IgG stability and minimization of cytotoxicity.
[So] Source:Mater Sci Eng C Mater Biol Appl;71:744-754, 2017 Feb 01.
[Is] ISSN:1873-0191
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Gold nanorods (AuNRs) used for biomedical applications could be encountered by biomolecules in the bloodstream, of which IgG is the most abundant antibody. With a view to mitigate their side effect on encountered proteins, the effect of Au concentration (5-40µM) and functionalization (CTAB-positive;PSS-negative; PEG-neutral) of AuNRs was investigated on the stability of a model protein, IgG (1µM). Electron microscopic images and particle size analyses indicated least aggregation behavior for PEG-AuNRs, which can be correlated to their neutral charge (from zeta potential analyses) or stearic hindrance of PEG chains. Variations in tryptophan domain were probed by UV-visible absorption and fluorescence quenching studies. Synchronous fluorescence study helped to provide information regarding variations in the hydrophobic region of IgG. The denaturation studies also indicated the stability of AuNR-IgG complex formation. These studies showed that positively charged IgG (pI: 7.8±1.0) was mostly affected by negatively charged PSS-AuNRs and least affected by PEG-AuNRs. This was verified by secondary structural investigations performed using CD and FTIR spectroscopy. For cytotoxicity studies on human lymphocytes, CTAB-AuNRs are known to show higher toxicity compared to PSS-AuNRs and PEG-AuNRs (least). Though PSS-functionalized AuNRs were shown to affect cells to a lesser degree based on the negative charge of cell membrane, they could hamper with positively charged biomolecules in the bloodstream before they reach the target, which must also be considered for choosing the right AuNR functionalization. Thus, this work indicates the effect of different AuNR functionalization on protein and cellular toxicity and stresses the necessity to use neutral particles to mitigate their side effect for theranostic applications.
[Mh] Termos MeSH primário: Ouro/farmacologia
Imunoglobulina G/química
Nanotubos/química
[Mh] Termos MeSH secundário: Adulto
Aminoácidos Aromáticos/análise
Morte Celular/efeitos dos fármacos
Sobrevivência Celular
Dicroísmo Circular
Difusão Dinâmica da Luz
Seres Humanos
Interações Hidrofóbicas e Hidrofílicas
Linfócitos/citologia
Nanotubos/ultraestrutura
Tamanho da Partícula
Polietilenoglicóis/química
Estabilidade Proteica/efeitos dos fármacos
Estrutura Secundária de Proteína
Espectrometria de Fluorescência
Espectrofotometria Ultravioleta
Espectroscopia de Infravermelho com Transformada de Fourier
Eletricidade Estática
Propriedades de Superfície
Termodinâmica
Adulto Jovem
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids, Aromatic); 0 (Immunoglobulin G); 30IQX730WE (Polyethylene Glycols); 7440-57-5 (Gold)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170926
[Lr] Data última revisão:
170926
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161219
[St] Status:MEDLINE



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