38 research outputs found

    Study of advanced rheumatoid arthritis

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    INTRODUCTION: Rheumatic diseases are considered public health problems affecting millions of people worldwide resulting in high and rising health-care costs. In this work, Fourier Transform Infrared spectroscopy associated to Partial Least Square regression (PLS) analysis was used to diagnose rheumatoid arthritis (RA) from human serum. METHODS: The sera of 94 individuals were collected, which included 47 from rheumatic patients and 47 from healthy individuals. The results from PLS analysis were compared to standard clinical trials such as anti-citrullinated peptide antibodies, C- Reactive protein, and Rheumatoid factor. RESULTS: For clinical diagnosis, the anti-citrullinated peptide antibodies of second generation proved to be the most specific to diagnosis rheumatoid arthritis even after long periods of drug therapy. CONCLUSIONS: The qualitative PLS analysis has shown higher values of IgM of RA group, but the difference was very small. The RA patients were under medication, which interfered with the IgM concentration.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Universidade do Vale do Paraíba Instituto de Pesquisa e DesenvolvimentoUniversidade Federal de São Paulo (UNIFESP) Departamento de Medicina Divisão de ReumatologiaUNIFESP, Depto. de Medicina Divisão de ReumatologiaSciEL

    Morphological And Chemical Changes In Dentin After Using Endodontic Agents: Fourier Transform Raman Spectroscopy, Energy-dispersive X-ray Fluorescence Spectrometry, And Scanning Electron Microscopy Study.

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    We examine the morphological and chemical changes in the pulp chamber dentin after using endodontic agents by scanning electron microscopy (SEM), Fourier transform Raman spectroscopy (FT-Raman), and micro energy-dispersive x-ray fluorescence spectrometry (μEDXRF). Thirty teeth were sectioned exposing the pulp chamber and divided by six groups (n=5): NT-no treatment; CHX-2% chlorhexidine; CHXE-2% chlorhexidine+17% EDTA; E-17% EDTA; SH5-5.25% NaOCl; SH5E-5.25% NaOCl+17% EDTA. The inorganic and organic content was analyzed by FT-Raman. μEDXRF examined calcium (Ca) and phosphorus (P) content as well as Ca/P ratio. Impressions of specimens were evaluated by SEM. Data were submitted to Kruskal-Wallis and Dunn tests (pNT=SH5E>CHX>E>CHXE). CHXE and E presented the highest Ca/P ratio values compared to the other groups (p<0.05). The SEM images in the EDTA-treated groups had the highest number of open tubules. Erosion in the tubules was observed in CHX and SH5E groups. Endodontic agents change the inorganic and organic content of pulp chamber dentin. NaOCl used alone, or in association with EDTA, was the most effective agent considering chemical and morphological approaches.1707500

    Effects of various hydrogen peroxide bleaching concentrations and number of applications on enamel

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    AIM:To evaluate the effects of three hydrogen peroxide (HP) concentrations on enamel mineral content (MC), following three peroxide applications and using three methods to measure the MC.METHODS : Forty samples were obtained from bovine incisors and randomly divided into 4 groups (n=10). The control group remained untreated, while the experimental groups were tested for three HP concentrations (10%, 35% and 50%). The HP gel was applied 3 times on the enamel surface for 30 min per application and the samples were analyzed after each application. The MC of the enamel was determined before and after bleaching using Fourier transform (FT-Raman) spectroscopy and micro energy-dispersive x-ray fluorescence spectrometry (&#181;EDXRF). The calcium (Ca) lost from the bleached enamel was quantified with an atomic absorption spectrometer (AAS). The data were analyzed statistically by ANOVA, Tukey and Dunnett&#180;s tests (p&lt;0.05).RESULTS:The FT-Raman showed a decrease in MC for all bleaching treatments, without influence of the different HP concentrations or the number of applications. &#181;EDXRF did not detect any changes in MC.CONCLUSIONS:Ca loss was observed by the AAS, with no difference among the three HP concentrations. The FT-Raman and AAS analyses detected MC reduction and Ca loss after HP bleaching.222

    Diagnóstico diferencial no melanoma primário e metastático por espectroscopia FT-Raman

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    PURPOSE: To qualify the FT-Raman spectral data of primary and metastatic cutaneous melanoma in order to obtain a differential diagnosis. METHODS: Ten normal human skin samples without any clinical or histopathological alterations, ten cutaneous melanoma fragments, and nine lymph node metastasis samples were used; 105, 140 and 126 spectra were obtained respectively. Each sample was divided into 2 or 3 fragments of approximately 2 mm³ and positioned in the Raman spectrometer sample holder in order to obtain the spectra; a monochrome laser light Nd:YAG at 1064 nm was used to excite the inelastic effect. RESULTS: To differentiate the three histopathological groups according to their characteristics extracted from the spectra, data discriminative analysis was undertaken. Phenylalanine, DNA, and Amide-I spectral variables stood out in the differentiation of the three groups. The percentages of correctly classified groups based on Phenylalanine, DNA, and Amide-I spectral features was 93.1%. CONCLUSION: FT-Raman spectroscopy is capable of differentiating melanoma from its metastasis, as well as from normal skin.OBJETIVO: Qualificar os dados espectrais FT-Raman do melanoma cutâneo primário e metastático e assim realizar o diagnóstico diferencial. MÉTODOS: Foram utilizadas amostras de 10 fragmentos de pele sem alterações clínicas ou histopatológicas, 10 de melanomas cutâneos e 9 de metástases linfonodais; 105, 140 and 126 espectros foram obtidos respectivamente. Cada amostra foi dividida em 2 ou 3 frações de 2 mm³ e posicionada no porta amostras do espectrômetro Raman para obtenção dos espectros, por meio da excitação do espalhamento inelástico pelo laser de Nd:YAG em 1064 nm incididos na amostra. RESULTADOS: Para diferenciar os três grupos formados de acordo com as características fornecidas pelos espectros, realizamos a análise discriminante dos dados. As variáveis espectrais Fenilalanina, DNA e Amida-I se destacaram na capacidade de diferenciação dos três grupos histológicos. A porcentagem de classificação correta utilizando estes critérios foi de 93,1%; o que mostra a eficiência da análise realizada. CONCLUSÃO: A espectroscopia FT-Raman é capaz de diferenciar o melanoma de sua metástase, assim como da pele normal.UNIFESPUniversidade Federal de São Paulo (UNIFESP) Department of SurgeryPathology DepartmentPathology Department Federal University of ABC Head of Center for Human and Natural Sciences (CCNH)UNIVAP Institute of Research and Development Head of Biomedical Vibrational Spectroscopy LaboratoryUniversidade Federal de São Paulo (UNIFESP) Department of Surgery Head of Division of Plastic SurgeryUNIFESP, Department of SurgeryUNIFESP, Department of Surgery Head of Division of Plastic SurgerySciEL

    Effect of different doses of creatine on the bone in thirty days of supplementation in mice: FT-Raman study

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    Abstract. In this study, Raman spectroscopy was employed in order to provide information about the effects of different doses of creatine on bone tissue composition of phosphate apatite (960 cm −1 ), carbonate apatite (1170 cm −1 ) representing the mineral content and collagen matrix (amide I, 1665 cm −1 ). The animals (27 Balb-C male) were divided into three groups (n = 9 per group): control (CON), supplemented with 0.5 g/kg (Cre-0.5) and with 2.0 g/kg (Cre-2.0) creatine. The experiment was carried out for thirty days. After this time, the right femur of each animal was harvested. The specimens were assessment by FT-Raman spectroscopy and in a total of 81 spectra were acquired in the medial diaphysis of the femur. The Raman data strongly suggest that only the creatine supplementation of 0.5 g/kg effective to the bone constitution. Furthermore, the present results demonstrate that creatine ingestion provokes decrease in the relative presence of carbonate in the chemical constitution of bones. The decrease in the carbonate content can be associated to a significantly bone resistance altered to several mammalians. The analysis evidenced that the mineral concentrations in the Raman spectroscopy could be a feasible method for non-invasive or minimally invasive assessment of bone tissue composition. Probably this high sensitivity can be employed to determine spectral profiles, such as wavelength of maximum absorption and maximum intensity of absorption of each wavelength, of several bone diseases

    CARACTERIZAÇÃO BIOQUÍMICA DE LINFONODOS NORMAIS, COMPROMETIDOS E LESÕES CERVICAIS POR ESPECTROSCOPIA RAMAN

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    Os linfonodos fazem parte do conjunto de órgãos linfoides pertencentes ao sistema linfático, considerados os filtros da linfa por serem ricos em células de defesa. Uma das causas de seu comprometimento é a invasão de células neoplásicas. A biópsia com posterior exame histológico constitui o exame padrão ouro no diagnóstico. Porém, estudos questionam a eficácia desta técnica, devido a perda da arquitetura celular. Neste sentido, o trabalho teve como objetivo mostrar as diferenças entre linfonodos normais e comprometidos por células tumorais. Para isto, foi utilizado a espectroscopia Raman na caracterização bioquímica de linfonodos normais e comprometidos além de lesões cervicais. Os resultados mostraram uma taxa de sensibilidade de 71,4%, especificidade de 80% e acurácia de 75% na discriminação dos tecidos. Portanto, a espectroscopia Raman se mostrou uma importante ferramenta no auxílio diagnóstico
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