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  1 / 18769 MEDLINE  
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[PMID]:29324795
[Au] Autor:Iyer JK; Dickey A; Rouhani P; Kaul A; Govindaraju N; Singh RN; Kaul R
[Ad] Endereço:Department of Biochemistry and Microbiology, Oklahoma State University-Center for Health Sciences, Tulsa, Oklahoma, United States of America.
[Ti] Título:Nanodiamonds facilitate killing of intracellular uropathogenic E. coli in an in vitro model of urinary tract infection pathogenesis.
[So] Source:PLoS One;13(1):e0191020, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:About 25-44% of women will experience at least one episode of recurrent UTI and the causative agent in over 70% of UTI cases is uropathogenic Escherichia coli (UPEC). UPEC cause recurrent UTI by evading the bladder's innate immune system through internalization into the bladder epithelium where antibiotics cannot reach or be effective. Thus, it is important to develop novel therapeutics to eliminate these intracellular pathogens. Nanodiamonds (NDs) are biocompatible nanomaterials that serve as promising candidates for targeted therapeutic applications. The objective of the current study was to investigate if 6 or 25 nm NDs can kill extracellular and intracellular UPEC in infected bladder cells. We utilized the human bladder epithelial cell line, T24, and an invasive strain of UPEC that causes recurrent UTI. We found that acid-purified 6 nm NDs displayed greater antibacterial properties towards UPEC than 25 nm NDs (11.5% vs 94.2% CFU/mL at 100 µg/mL of 6 and 25 nm, respectively; P<0.001). Furthermore, 6 nm NDs were better than 25 nm NDs in reducing the number of UPEC internalized in T24 bladder cells (46.1% vs 81.1% CFU/mL at 100 µg/mL of 6 and 25 nm, respectively; P<0.01). Our studies demonstrate that 6 nm NDs interacted with T24 bladder cells in a dose-dependent manner and were internalized in 2 hours through an actin-dependent mechanism. Finally, internalization of NDs was required for reducing the number of intracellular UPEC in T24 bladder cells. These findings suggest that 6 nm NDs are promising candidates to treat recurrent UTIs.
[Mh] Termos MeSH primário: Nanodiamantes
Infecções Urinárias/microbiologia
Escherichia coli Uropatogênica/efeitos dos fármacos
[Mh] Termos MeSH secundário: Linhagem Celular
Contagem de Colônia Microbiana
Seres Humanos
Técnicas In Vitro
Microscopia Confocal
Microscopia Eletrônica de Transmissão
Análise Espectral Raman
Bexiga Urinária/citologia
Bexiga Urinária/microbiologia
Bexiga Urinária/ultraestrutura
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Nanodiamonds)
[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:180112
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0191020


  2 / 18769 MEDLINE  
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[PMID]:29214531
[Au] Autor:Zhang J; Liang L; Guan X; Deng R; Qu H; Huang D; Xu S; Liang C; Xu W
[Ad] Endereço:State Key Laboratory of Supramolecular Structure and Materials, Institute of Theoretical Chemistry, Jilin University, Changchun, Jilin, 130012, China.
[Ti] Título:In situ, accurate, surface-enhanced Raman scattering detection of cancer cell nucleus with synchronous location by an alkyne-labeled biomolecular probe.
[So] Source:Anal Bioanal Chem;410(2):585-594, 2018 Jan.
[Is] ISSN:1618-2650
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:A surface-enhanced Raman scattering (SERS) method for in situ detection and analysis of the intranuclear biomolecular information of a cell has been developed based on a small, biocompatible, nuclear-targeting alkyne-tagged deoxyribonucleic acid (DNA) probe (5-ethynyl-2'-deoxyuridine, EDU) that can specially accumulate in the cell nucleus during DNA replications to precisely locate the nuclear region without disturbance in cell biological activities and functions. Since the specific alkyne group shows a Raman peak in the Raman-silent region of cells, it is an interior label to visualize the nuclear location synchronously in real time when measuring the SERS spectra of a cell. Because no fluorescent-labeled dyes were used for locating cell nuclei, this method is simple, nondestructive, non- photobleaching, and valuable for the in situ exploration of vital physiological processes with DNA participation in cell organelles. Graphical abstract A universal strategy was developed to accurately locate the nuclear region and obtain precise molecular information of cell nuclei by SERS.
[Mh] Termos MeSH primário: Alquinos/análise
Núcleo Celular/patologia
Desoxiuridina/análogos & derivados
Neoplasias/patologia
[Mh] Termos MeSH secundário: Núcleo Celular/química
Desoxiuridina/análise
Seres Humanos
Células MCF-7
Microscopia de Fluorescência/métodos
Neoplasias/química
Imagem Óptica/métodos
Análise Espectral Raman/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Alkynes); G373S00W2J (5-ethynyl-2'-deoxyuridine); W78I7AY22C (Deoxyuridine)
[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:171208
[St] Status:MEDLINE
[do] DOI:10.1007/s00216-017-0761-4


  3 / 18769 MEDLINE  
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[PMID]:28462910
[Au] Autor:Mihailescu IN; Bociaga D; Popescu-Pelin G; Stan GE; Duta L; Socol G; Chifiriuc MC; Bleotu C; Lazar V; Husanu MA; Zgura I; Miculescu F; Negut I; Hapenciuc C
[Ad] Endereço:National Institute for Lasers, Plasma and Radiation Physics, 077125 Magurele, Romania.
[Ti] Título:Optimized silicon reinforcement of carbon coatings by pulsed laser technique for superior functional biomedical surfaces fabrication.
[So] Source:Biofabrication;9(2):025029, 2017 Jun 01.
[Is] ISSN:1758-5090
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:We report on the fabrication of silicon-reinforced carbon (C:Si) structures by combinatorial pulsed laser deposition to search for the best design for a new generation of multi-functional coated implants. The synthesized films were characterized from the morphological, structural, compositional, mechanical and microbiological points of view. Scanning electron microscopy revealed the presence, on top of the deposited layers, of spheroid particulates with sizes in the micron range. No micro-cracks or delaminations were observed. Energy dispersive x-ray spectroscopy and grazing incidence x-ray diffraction pointed to the existence of a C to Si compositional gradient from one end of the film to the other. Raman investigation revealed a relatively high sp hybridization of up to 80% at 40-48 mm apart from the edge with higher C content. Si addition was demonstrated to significantly increase C:Si film bonding to the substrate, with values above the ISO threshold for coatings to be used in high-loading biomedical applications. Surface energy studies pointed to an increase in the hydrophilic character of the deposited structures along with Si content up to 52 mN m . In certain cases, the Si-reinforced C coatings elicited an antimicrobial biofilm action. The presence of Si was proven to be benign to HEp-2 cells of human origin, without interfering with their cellular cycle. On this basis, reliable C:Si structures with good adherence to the substrate and high efficiency against microbial biofilms can be developed for implant coatings and other advanced medical devices.
[Mh] Termos MeSH primário: Tecnologia Biomédica/métodos
Carbono/química
Materiais Revestidos Biocompatíveis/química
Lasers
Silício/química
[Mh] Termos MeSH secundário: Ciclo Celular
Forma Celular
Seres Humanos
Teste de Materiais
Testes de Sensibilidade Microbiana
Microscopia Eletrônica de Varredura
Espectrometria por Raios X
Análise Espectral Raman
Propriedades de Superfície
Água/química
Difração de Raios X
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Coated Materials, Biocompatible); 059QF0KO0R (Water); 7440-44-0 (Carbon); Z4152N8IUI (Silicon)
[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:170503
[St] Status:MEDLINE
[do] DOI:10.1088/1758-5090/aa7076


  4 / 18769 MEDLINE  
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[PMID]:29412223
[Au] Autor:Genari B; Leitune VCB; Jornada DS; Aldrigui BR; Pohlmann AR; Guterres SS; Samuel SMW; Collares FM
[Ad] Endereço:Universidade Federal do Rio Grande do Sul - UFRGS, School of Dentistry, Dental Materials Laboratory, Porto Alegre, RS, Brazil.
[Ti] Título:Effect on adhesion of a nanocapsules-loaded adhesive system.
[So] Source:Braz Oral Res;32:e008, 2018 Feb 01.
[Is] ISSN:1807-3107
[Cp] País de publicação:Brazil
[La] Idioma:eng
[Ab] Resumo:This study aimed to evaluate the in situ degree of conversion, contact angle, and immediate and long-term bond strengths of a commercial primer and an experimental adhesive containing indomethacin- and triclosan-loaded nanocapsules (NCs). The indomethacin- and triclosan-loaded NCs, which promote anti-inflammatory and antibacterial effects through controlled release, were incorporated into the primer at a concentration of 2% and in the adhesive at concentrations of 1, 2, 5, and 10%. The in situ degree of conversion (DC, n=3) was evaluated by micro-Raman spectroscopy. The contact angle of the primer and adhesive on the dentin surface (n = 3) was determined by an optical tensiometer. For the microtensile bond strength µTBS test (12 teeth per group), stick-shaped specimens were tested under tensile stress immediately after preparation and after storage in water for 1 year. The data were analyzed using two-way ANOVA, three-way ANOVA and Tukey's post hoc tests with α=0.05. The use of the NC-loaded adhesive resulted in a higher in situ degree of conversion. The DC values varied from 75.07 ± 8.83% to 96.18 ± 0.87%. The use of NCs in only the adhesive up to a concentration of 5% had no influence on the bond strength. The contact angle of the primer remained the same with and without NCs. The use of both the primer and adhesive with NCs (for all concentrations) resulted in a higher contact angle of the adhesive. The longitudinal µTBS was inversely proportional to the concentration of NCs in the adhesive system, exhibiting decreasing values for the groups with primer containing NCs and adhesives with increasing concentrations of NCs. Adhesives containing up to 5% of nanocapsules and primer with no NCs maintained the in situ degree of conversion, contact angle, and immediate and long-term bond strengths. Therefore, the NC-loaded adhesive can be an alternative method for combining the bond performance and therapeutic effects. The use of an adhesive with up to 5% nanocapsules containing indomethacin and triclosan and a primer with no nanocapsules maintained the long-term bond performance.
[Mh] Termos MeSH primário: Colagem Dentária/métodos
Indometacina/química
Nanocápsulas/química
Cimentos de Resina/química
Triclosan/química
[Mh] Termos MeSH secundário: Análise de Variância
Animais
Bovinos
Falha de Restauração Dentária
Dentina/efeitos dos fármacos
Teste de Materiais
Transição de Fase/efeitos dos fármacos
Polimerização/efeitos dos fármacos
Valores de Referência
Reprodutibilidade dos Testes
Análise Espectral Raman
Propriedades de Superfície/efeitos dos fármacos
Resistência à Tração
Fatores de Tempo
[Pt] Tipo de publicação:EVALUATION STUDIES; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Nanocapsules); 0 (Resin Cements); 4NM5039Y5X (Triclosan); 90881-69-9 (Scotchbond); XXE1CET956 (Indomethacin)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180307
[Lr] Data última revisão:
180307
[Sb] Subgrupo de revista:D; IM
[Da] Data de entrada para processamento:180208
[St] Status:MEDLINE


  5 / 18769 MEDLINE  
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[PMID]:29190078
[Au] Autor:Gonzalez P; Vileno B; Bossak K; El Khoury Y; Hellwig P; Bal W; Hureau C; Faller P
[Ad] Endereço:Institut de Chimie, UMR 7177, CNRS, Université de Strasbourg , 4 rue Blaise Pascal 67000, Strasbourg, France.
[Ti] Título:Cu(II) Binding to the Peptide Ala-His-His, a Chimera of the Canonical Cu(II)-Binding Motifs Xxx-His and Xxx-Zzz-His.
[So] Source:Inorg Chem;56(24):14870-14879, 2017 Dec 18.
[Is] ISSN:1520-510X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Peptides and proteins with the N-terminal motifs NH -Xxx-His and NH -Xxx-Zzz-His form well-established Cu(II) complexes. The canonical peptides are Gly-His-Lys and Asp-Ala-His-Lys (from the wound healing factor and human serum albumin, respectively). Cu(II) is bound to NH -Xxx-His via three nitrogens from the peptide and an external ligand in the equatorial plane (called 3N form here). In contrast, Cu(II) is bound to NH -Xxx-Zzz-His via four nitrogens from the peptide in the equatorial plane (called 4N form here). These two motifs are not mutually exclusive, as the peptides with the sequence NH -Xxx-His-His contain both of them. However, this chimera has never been fully explored. In this work, we use a multispectroscopic approach to analyze the Cu(II) binding to the chimeric peptide Ala-His-His (AHH). AHH is capable of forming the 3N- and 4N-type complexes in a pH dependent manner. The 3N form predominates at pH ∼ 4-6.5 and the 4N form at ∼ pH 6.5-10. NMR experiments showed that at pH 8.5, where Cu(II) is almost exclusively bound in the 4N form, the Cu(II)-exchange between AHH or the amidated AHH-NH is fast, in comparison to the nonchimeric 4N form (AAH). Together, the results show that the chimeric AHH can access both Cu(II) coordination types, that minor changes in the second (or further) coordination sphere can impact considerably the equilibrium between the forms, and that Cu kinetic exchange is fast even when Cu-AHH is mainly in the 4N form.
[Mh] Termos MeSH primário: Complexos de Coordenação/química
Cobre/química
Oligopeptídeos/química
[Mh] Termos MeSH secundário: Sítios de Ligação
Dimerização
Espectroscopia de Ressonância de Spin Eletrônica
Concentração de Íons de Hidrogênio
Cinética
Espectroscopia de Ressonância Magnética
Potenciometria
Conformação Proteica
Proteínas/química
Espectroscopia de Infravermelho com Transformada de Fourier
Análise Espectral Raman
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Ala-His-His); 0 (Coordination Complexes); 0 (Oligopeptides); 0 (Proteins); 789U1901C5 (Copper)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180228
[Lr] Data última revisão:
180228
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171201
[St] Status:MEDLINE
[do] DOI:10.1021/acs.inorgchem.7b01996


  6 / 18769 MEDLINE  
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[PMID]:28460336
[Au] Autor:Shashni B; Horiguchi Y; Kurosu K; Furusho H; Nagasaki Y
[Ad] Endereço:Department of Materials Science, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tennoudai 1-1-1, Tsukuba, Ibaraki, 305-8573, Japan.
[Ti] Título:Application of surface enhanced Raman spectroscopy as a diagnostic system for hypersialylated metastatic cancers.
[So] Source:Biomaterials;134:143-153, 2017 Jul.
[Is] ISSN:1878-5905
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Early diagnosis of metastatic cancers could greatly limit the number of cancer-associated deaths. Aberrant surface expression of sialic acid (hypersialylation) on tumors correlating with metastatic incidence and its involvement in tumorigenesis and progression is widely reported; hence detection of hypersialylated tumors may be an effective strategy to identify metastatic cancers. We herein report on the application of phenylboronic acid-installed PEGylated gold nanoparticles coupled with Toluidine blue O (T/BA-GNPs) as SERS probes to target surface sialic acid (N-acetylneuraminic acid, Neu5Ac). Strong SERS signals from metastatic cancer cell lines (breast cancer; MDA-MB231 and colon cancer; Colon-26) were observed, contrary to non-metastatic MCF-7 cells (breast cancer). The detected SERS signals from various cancer cell lines correlated with their reported metastatic potential, implying that our T/BA-GNP based SERS system was capable of distinguishing the metastaticity of cells based on the surface Neu5Ac density. T/BA-GNP based SERS system could also significantly differentiate between hypersialylated tumor tissues and healthy tissues with high SERS signal to noise ratio, due to plasmon coupling between the specifically aggregated functionalized GNPs. Furthermore, we also confirmed reduction in SERS signals from MDA-MB231 surface upon treatment with our original reactive oxygen species (ROS)-scavenging polymeric micelle, nitroxide-radical containing nanoparticles (RNPs). The ROS-mediated abrogation of sialylation by impairing the activation of NF-κB-sialyltransferase signaling cascade upon RNP treatment was confirmed by expression studies and the T/BA-GNPs based SERS system. The aforementioned findings thus, establish T/BA-GNPs based SERS as a potential cytodiagnostic system to detect hypersialylated metastatic tumors and RNPs as anti-metastatic cancer drug candidates.
[Mh] Termos MeSH primário: Ácidos Borônicos/uso terapêutico
Ácido N-Acetilneuramínico/metabolismo
Análise Espectral Raman/métodos
[Mh] Termos MeSH secundário: Animais
Western Blotting
Ácidos Borônicos/química
Neoplasias da Mama/tratamento farmacológico
Neoplasias da Mama/metabolismo
Linhagem Celular Tumoral
Cromatografia em Gel
Ouro/química
Seres Humanos
Células MCF-7
Nanopartículas Metálicas/química
Camundongos
NF-kappa B/metabolismo
Espécies Reativas de Oxigênio/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Boronic Acids); 0 (NF-kappa B); 0 (Reactive Oxygen Species); 7440-57-5 (Gold); GZP2782OP0 (N-Acetylneuraminic Acid); L12H7B02G5 (benzeneboronic acid)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180228
[Lr] Data última revisão:
180228
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170502
[St] Status:MEDLINE


  7 / 18769 MEDLINE  
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[PMID]:29444032
[Au] Autor:Zhang Z; Huerta-Viga A; Tan HS
[Ti] Título:Two-dimensional electronic-Raman spectroscopy.
[So] Source:Opt Lett;43(4):939-942, 2018 Feb 15.
[Is] ISSN:1539-4794
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:We present a new technique, two-dimensional electronic-Raman spectroscopy (2DER), which combines femtosecond stimulated Raman spectroscopy and a pulse-shaper-assisted 2D spectroscopic scheme for the actinic pump. The 2DER spectrum presents the initial actinic excitation wavelength with nanometer spectral resolution in the first axis and the detected stimulated Raman spectra in the second axis. We measured the correlation of the electronic and vibrational states in the photosynthetic accessory pigment ß-carotene and reveal its photoexcited state manifold.
[Mh] Termos MeSH primário: Elétrons
Análise Espectral Raman/métodos
[Mh] Termos MeSH secundário: beta Caroteno/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
01YAE03M7J (beta Carotene)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180226
[Lr] Data última revisão:
180226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180215
[St] Status:MEDLINE
[do] DOI:10.1364/OL.43.000939


  8 / 18769 MEDLINE  
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[PMID]:29376153
[Au] Autor:Das R; Rajender G; Giri PK
[Ad] Endereço:Department of Physics, Indian Institute of Technology Guwahati, Guwahati - 781039, India. giri@iitg.ernet.in.
[Ti] Título:Anomalous fluorescence enhancement and fluorescence quenching of graphene quantum dots by single walled carbon nanotubes.
[So] Source:Phys Chem Chem Phys;20(6):4527-4537, 2018 Feb 07.
[Is] ISSN:1463-9084
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:We explore the mechanism of the fluorescence enhancement and fluorescence quenching effect of single walled carbon nanotubes (SWCNTs) on highly fluorescent graphene quantum dots (GQDs) over a wide range of concentrations of SWCNTs. At very low concentrations of SWCNTs, the fluorescence intensity of the GQDs is enhanced, while at higher concentrations, systematic quenching of fluorescence is observed. The nature of the Stern-Volmer plot for the latter case was found to be non-linear indicating a combined effect of dynamic and static quenching. The contribution of the dynamic quenching component was assessed through the fluorescence lifetime measurements. The contribution of static quenching is confirmed from the red shift of the fluorescence spectra of the GQDs after addition of SWCNTs. The fluorescence intensity is first enhanced at very low concentration due to improved dispersion and higher absorption by GQDs, while at higher concentration, the fluorescence of GQDs is quenched due to the complex formation and associated reduction of the radiative sites of the GQDs, which is confirmed from time-resolved fluorescence measurements. Laser confocal microscopy imaging provides direct evidence of the enhancement and quenching of fluorescence at low and high concentrations of SWCNTs, respectively. This study provides an important insight into tuning the fluorescence of GQDs and understanding the interaction between GQDs and different CNTs, which is important for bio-imaging and drug delivery applications.
[Mh] Termos MeSH primário: Grafite/química
Nanotubos de Carbono/química
Pontos Quânticos/química
[Mh] Termos MeSH secundário: Microscopia Confocal
Espectrofotometria
Análise Espectral Raman
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Nanotubes, Carbon); 7782-42-5 (Graphite)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180226
[Lr] Data última revisão:
180226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180130
[St] Status:MEDLINE
[do] DOI:10.1039/c7cp06994d


  9 / 18769 MEDLINE  
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[PMID]:29372919
[Au] Autor:Karaballi RA; Merchant S; Power SR; Brosseau CL
[Ad] Endereço:Department of Chemistry, Saint Mary's University, Halifax, Nova Scotia B3H 3C3, Canada. christa.brosseau@smu.ca.
[Ti] Título:Electrochemical surface-enhanced Raman spectroscopy (EC-SERS) study of the interaction between protein aggregates and biomimetic membranes.
[So] Source:Phys Chem Chem Phys;20(6):4513-4526, 2018 Feb 07.
[Is] ISSN:1463-9084
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Human diseases characterized by the uncontrolled deposition of insoluble extracellular protein aggregates are collectively referred to as amyloidoses. Such diseases include Alzheimer's, Parkinson's, Huntington's, and prion disease. In Alzheimer's disease, it is believed that amyloid-ß proteins may be responsible for pore and defect formation within cellular membranes, leading to a breakdown of cellular homeostasis causing eventual neuronal death. This theory is referred to as the amyloid pore hypothesis of Alzheimer's disease. In this work, the interaction between a model amyloid-forming protein (insulin) and a biomimetic membrane was studied at the molecular level. Protein at different stages of aggregation was allowed to interact with a biomimetic membrane formed on a nanostructured substrate using Langmuir-Blodgett/Langmuir-Schaefer deposition. Electrochemical surface-enhanced Raman spectroscopy (EC-SERS) was used to monitor the molecular level changes occurring as a result of this interaction. Based on the results it was observed that oligomers and protofibrils caused the most significant membrane deterioration whilst native protein appeared to play a protective role. To the best of our knowledge, this work represents the first EC-SERS investigation of protein aggregate-biomembrane interactions, and highlights the usefulness of this tool for studying complex biomolecular interactions.
[Mh] Termos MeSH primário: Amiloide/química
Biomimética
Insulina/química
Bicamadas Lipídicas/química
Agregados Proteicos
[Mh] Termos MeSH secundário: Amiloide/metabolismo
Técnicas Eletroquímicas
Eletrodos
Seres Humanos
Insulina/metabolismo
Bicamadas Lipídicas/metabolismo
Nanopartículas Metálicas/química
Microscopia Eletrônica de Varredura
Microscopia Eletrônica de Transmissão
Nefelometria e Turbidimetria
Prata/química
Análise Espectral Raman
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amyloid); 0 (Insulin); 0 (Lipid Bilayers); 0 (Protein Aggregates); 3M4G523W1G (Silver)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180226
[Lr] Data última revisão:
180226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180127
[St] Status:MEDLINE
[do] DOI:10.1039/c7cp06838g


  10 / 18769 MEDLINE  
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[PMID]:29260810
[Au] Autor:Chang S; Mizuno M; Ishikawa H; Mizutani Y
[Ad] Endereço:Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan. mztn@chem.sci.osaka-u.ac.jp.
[Ti] Título:Tertiary dynamics of human adult hemoglobin fixed in R and T quaternary structures.
[So] Source:Phys Chem Chem Phys;20(5):3363-3372, 2018 Jan 31.
[Is] ISSN:1463-9084
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Protein dynamics of human adult hemoglobin and its mutants restricted in R and T quaternary states following ligand photolysis were studied by time-resolved resonance Raman spectroscopy. In the time-resolved spectra, we observed spectral changes of in-plane stretching modes of heme and the iron-histidine stretching mode of the Fe-His bond for all the hemoglobin samples. The ßD99N mutant, which adopts the R state in both the ligand-bound and the deoxy forms, showed similar temporal behaviors in time-resolved resonance Raman spectra as wild-type recombinant hemoglobin until 10 µs, consistent with the fact that the mutant undergoes only the tertiary structural changes in the R state. The ßN102T mutant, which adopts the T state in both the ligand-bound and the deoxy forms, showed much slower tertiary structural changes, suggesting that the EF helical motion is decelerated by the change of the intersubunit interactions. The present data indicate that the allosteric kinetic response between the interhelical hydrogen bonds of the EF helices and the intersubunit hydrogen bonds is bidirectional. The implications of these results for understanding the allosteric pathway of Hb are discussed in detail.
[Mh] Termos MeSH primário: Hemoglobinas/química
[Mh] Termos MeSH secundário: Adulto
Heme/química
Heme/metabolismo
Hemoglobinas/genética
Hemoglobinas/metabolismo
Histidina/química
Histidina/metabolismo
Seres Humanos
Ligações de Hidrogênio
Mutagênese Sítio-Dirigida
Estrutura Quaternária de Proteína
Proteínas Recombinantes/biossíntese
Proteínas Recombinantes/química
Proteínas Recombinantes/isolamento & purificação
Análise Espectral Raman
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Hemoglobins); 0 (Recombinant Proteins); 42VZT0U6YR (Heme); 4QD397987E (Histidine)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180226
[Lr] Data última revisão:
180226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171221
[St] Status:MEDLINE
[do] DOI:10.1039/c7cp06287g



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