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1.
Rehabilitacion (Madr) ; 53(2): 85-92, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-31186101

RESUMO

Early specialisation in sports continues to increase and is a risk factor for the incidence of injuries in young athletes. In overhead athletes, the shoulder is the most affected joint, related to a combination of impingement and glenohumeral instability, as well as musculoskeletal immaturity. Identification of risk factors and rehabilitation is usually an effective recovery option for these athletes.


Assuntos
Traumatismos em Atletas/reabilitação , Lesões do Ombro/reabilitação , Dor de Ombro/reabilitação , Adolescente , Traumatismos em Atletas/complicações , Humanos , Lesões do Ombro/complicações , Lesões do Ombro/diagnóstico , Dor de Ombro/etiologia , Adulto Jovem
3.
Phys Chem Chem Phys ; 19(40): 27888-27891, 2017 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-28971192

RESUMO

The differences between alternative approaches for quantifying the complex effect of the electronic structure of charged metal-molecule hybrids in SERS (the so-called chemical enhancement mechanism) are highlighted. The discussion is focussed on the predictions obtained by using different methodological tools for modelling the role of the electrode potential in the SERS relative intensities. Finite electric fields are used in the commented paper for this purpose, but we have found some inconsistences in the results and the method for calculating the Raman intensities is not made sufficiently clear, which prevents the assessment of the results.

4.
Food Funct ; 7(6): 2800-10, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-27227510

RESUMO

Breast cancer is the second most common type of cancer worldwide and the most frequent among women, being the fifth cause of death from neoplastic disease. Since this is an oxidative-stress related neoplasia, it is largely preventable. A dietary isoflavone abundant in soybean - daidzein - is currently being investigated owing to its chemopreventive and/or chemotherapeutic properties towards the human MDA-MB-231 (metastatic, estrogen-unresponsive) and MCF-7 (estrogen-responsive) breast cancer cell lines. Biological assays for evaluation of antitumour and anti-invasive activities were combined with state-of-the-art vibrational microspectroscopy techniques. At 50 and 100 µM concentrations and 48 h incubation time, daidzein was found to induce a marked decrease in cell viability (ca. 50%) for MDA-MB-231 and MCF-7 cells (respectively ca. 50% and 42%) and 40% inhibition of cell migration. MicroRaman analysis of fixed cells upon exposure to this isoflavone unveiled its metabolic impact on both cell lines. Multivariate data analysis (unsupervised PCA) led to a clear discrimination between the control and DAID-exposed cells, with distinctive effects on their biochemical profile, particularly regarding DNA, lipids and protein components, in a cell-dependent way. This is the first reported study on the impact of dietary antioxidants on cancer cells by microRaman techniques.


Assuntos
Antioxidantes/farmacologia , Isoflavonas/farmacologia , Análise Espectral Raman , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Estrogênios/metabolismo , Humanos , Células MCF-7 , Estresse Oxidativo/efeitos dos fármacos , Análise de Componente Principal , Glycine max/química
5.
J Colloid Interface Sci ; 465: 183-9, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26674234

RESUMO

Surface-Enhanced Raman Spectra (SERS) of methyl N-(1H-benzimidazol-2-yl)carbamate (MBC), usually named carbendazim, have been recorded on silver colloids at different pH values. In order to identify the neutral, protonated or deprotonated species of MBC that originate the SERS, the vibrational wavenumbers of these three isolated forms and linked to a silver atom have been predicted by carrying out DFT calculations. The results indicate that the active SERS species in the studied pH range correspond to the neutral MBC and its deprotonated ion in the amidate form. According to theoretical calculations, neutral MBC is linked to the metal through the imidazolic nitrogen atom, while the deprotonated MBC could be linked through the imidazolic nitrogen together with the amidic nitrogen atom or the carbonyl oxygen atom. Both adsorbed species, neutral and deprotonated, have the benzimidazolic ring orientated almost perpendicular to the silver surface and no molecular reorientation has been detected. pH of the bulk controls the relative abundance of the neutral MBC and its amidate anion which can be monitored through the intensities of the SERS bands recorded at about 1230 and 1270cm(-1). These two key bands correspond to the in-plane NH deformation of amidic and imidazolic groups, respectively.

6.
Phys Chem Chem Phys ; 17(4): 2326-9, 2015 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-25407303

RESUMO

DFT calculations predict that plasmon-like excitations in small metal clusters are able to selectively modify the relative intensities of specific SERS bands of adsorbed molecules. These electronic resonances provide new kinds of SERS selection rules which can explain the huge enhancement of mode 9a of pyridine in the spectra recorded at negative electrode potentials.

9.
Phys Chem Chem Phys ; 16(42): 22958-61, 2014 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-25255295

RESUMO

DFT calculations predict two different electronic structures of metal-molecule hybrids which are selected depending on the surface charge. While the metal-to-molecule CT states are very sensitive to the charge, the energies of the reverse molecule-to-metal CT processes are surprisingly not modified at all by the charge of the metal.

11.
Spectrochim Acta A Mol Biomol Spectrosc ; 109: 116-24, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23501725

RESUMO

The conformational preferences of a series of hydroxyflavones were studied by Raman and FTIR spectroscopies, coupled to Density Functional Theory calculations. Special attention was paid to the effect of hydroxyl substitution, due to its importance on the biological activity of these compounds. Their conformational preferences were found to be determined mainly by the orientation of the hydroxylic groups at C(7) and within the catechol moiety, leading to the occurrence of distinct conformers in the solid state. A complete assignment of the experimental spectra was carried out for these molecules, in the light of their most stable conformers and the corresponding predicted vibrational pattern.


Assuntos
Flavonas/química , Modelos Moleculares , Conformação Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
13.
Clin Biochem ; 45(7-8): 566-70, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22366373

RESUMO

BACKGROUND AND AIMS: Metabolic syndrome (MS) and type 2 diabetes are highly associated with an abnormal lipoprotein profile, which may be generated and accentuated by high cholesteryl ester transfer protein (CETP) activity. Given the difficulty in measuring CETP activity, the aim was to identify simple biochemical predictors of high CETP activity. DESIGN AND METHODS: Eighty five subjects at risk for type 2 diabetes were classified according to the presence of MS. Lipoprotein profile, HOMA-IR and endogenous CETP activity were evaluated. RESULTS: As expected, MS patients presented higher concentration of glucose, insulin, triglycerides and non-HDL-C and lower HDL-C levels. Moreover, MS patients exhibited increased HOMA-IR and CETP activity. Employing a ROC curve for MS, high CETP activity was defined as >250%ml⁻¹ h⁻¹. The predictive variables of high CETP were non-HDL-C≥160mg/dl (OR=11.1;95%IC=3.3-38.2;p<0.001) and HOMA-IR>2.1 (OR=4.4;95%IC=1.3-14.8;p<0.05). CONCLUSIONS: High non-HDL-C and insulin resistance were predictors for increased CETP activity which measurement is not accessible for clinical laboratories.


Assuntos
Proteínas de Transferência de Ésteres de Colesterol/metabolismo , HDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/patologia , Resistência à Insulina , Biomarcadores/sangue , Biomarcadores/metabolismo , Glicemia , Índice de Massa Corporal , Estudos de Casos e Controles , Proteínas de Transferência de Ésteres de Colesterol/sangue , HDL-Colesterol/metabolismo , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Humanos , Modelos Lineares , Masculino , Síndrome Metabólica/metabolismo , Síndrome Metabólica/patologia , Pessoa de Meia-Idade , Fatores de Risco , Circunferência da Cintura
14.
Rev Gastroenterol Mex ; 76(1): 73-8, 2011.
Artigo em Espanhol | MEDLINE | ID: mdl-21592911

RESUMO

Heterotopic pancreatic tissue in the stomach is an uncommon gastric subepithelial lesion. Is usually an asymptomatic condition which is found incidentally. As with other gastric subepithelial lesions, diagnosis can be challenging. Endoscopic forceps biopsy specimens are of little value. Endoscopic ultrasound findings are helpful in characterize this lesions, but they cannot absolutely determine the type of lesion or whether a lesion is benign or malignant. The sequence endosonography- cap assisted endoscopic mucosal resection allows en bloc resection of small gastric subepithelial lesions with low complication rates. We report a case of an ectopic pancreas of the antrum in the stomach that arises from the second layer of the gastric wall (muscularis mucosa) at endoscopic ultrasound that was removed en bloc with cap-assisted endoscopic mucosal resection technique in one endoscopic session without complications.


Assuntos
Coristoma/patologia , Pâncreas , Gastropatias/patologia , Adulto , Mucosa Gástrica/patologia , Humanos , Masculino
15.
Anal Chem ; 83(7): 2518-25, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21391577

RESUMO

Silver nanoparticles (NPs) functionalized with the molecular assembler bis-acridinium dication lucigenin (LG) have been used as a chemical sensor system to detect a group of polycyclic aromatic hydrocarbon (PAH) pollutants in a multicomponent mixture by means of surface-enhanced raman scattering (SERS). The effectiveness of this system was checked for a group of PAHs with different numbers of fused benzene rings, namely anthracene, pyrene, triphenylene, benzo[c]phenanthrene, chrysene, and coronene. In order to determine the host capacity of this sensor system, the self-assembly of the LG viologen on a metallic surface has been checked by analyzing SERS intensities of PAH bands at different LG concentrations. The NP-LG-analyte affinity is derived from the analysis of PAH band intensities at different concentrations of pollutants, the adsorption isotherm of each PAH on NP-LG cavities has been studied, and the corresponding adsorption constants have been evaluated. The limit of detection at trace-level concentration is confirmed by the presence of their characteristic fingerprint vibrational bands. The SERS spectra of PAH mixtures confirm that LG viologen dication shows a higher analytical selectivity to PAHs constituted by four fused benzene rings, mainly pyrene and benzo[c]phenanthrene, in agreement with their higher affinity which is also related to their better fit into the intermolecular LG cavities. As a conclusion, SERS spectra recorded on modified NP-LG surfaces are a powerful chemical tool to detect organic pollutants.

16.
Phys Chem Chem Phys ; 13(3): 1012-8, 2011 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-21063581

RESUMO

A SERS study of chromone 3-carboxylic acid adsorbed on silver colloids was undertaken, in order to assess the ability of this compound to accept electrons in charge transfer (CT) processes. Theoretical SERS intensities under photoinduced CT resonant conditions have been carried out for both the neutral and the deprotonated species allowing to conclude, by comparison with the experimental data, that the recorded SER corresponds to the anionic form of the acid linked to the metal. It was shown that the SERS-CT mechanism predominates for this particular compound, thus explaining the strong enhancement of the band at ca. 1600 cm(-1) assigned to the 8a ring stretching mode. The identification of CT processes is of the utmost importance for understanding the mechanism through which these benzopyranes may act as antioxidants.


Assuntos
Antioxidantes/química , Ácidos Carboxílicos/química , Cromonas/química , Benzopiranos/química , Coloides/química , Elétrons , Prata/química , Análise Espectral Raman
18.
Rev Gastroenterol Mex ; 75(3): 339-43, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20959188

RESUMO

Common bile duct (CBD) stones extraction is usually performed by endoscopic sphincterotomy followed by removal by either a Dormia basket or extraction balloon catheter. However, some stones due to their size are not amenable to these procedures and extracorporeal or mechanical lithotripsy devices need to be used. Mechanical lithotripsy involves usage of a basket that will be inevitably destroyed which increases cost to the patient and endoscopy unit. The use of extracorporeal wave shock lithotripsy is an alternative; however it is not available widely. Reports about the use of hydrostatic large caliber balloon dilator (HLCBD) aiding in the extraction of large caliber CBD stones have concluded that is a safe and feasible therapeutic alternative. We present the case of a 25 mm x 30 mm CBD stone that could not be extracted using conventional methods. CBD dilation using HLCBD was performed after endoscopic sphincterotomy in an attempt to avoid mechanical lithotripsy.


Assuntos
Doenças do Ducto Colédoco/cirurgia , Endoscopia/métodos , Cálculos Biliares/cirurgia , Esfinterotomia Endoscópica/métodos , Idoso , Doenças do Ducto Colédoco/complicações , Fluoroscopia , Cálculos Biliares/complicações , Humanos , Imageamento por Ressonância Magnética , Masculino , Resultado do Tratamento
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