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1.
NMR Biomed ; 33(3): e4234, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31825557

RESUMO

Magnetic resonance imaging (MRI) is the current gold standard for the diagnosis of brain tumors. However, despite the development of MRI techniques, the differential diagnosis of central nervous system (CNS) primary pathologies, such as lymphoma and glioblastoma or tumor-like brain lesions and glioma, is often challenging. MRI can be supported by in vivo magnetic resonance spectroscopy (MRS) to enhance its diagnostic power and multiproject-multicenter evaluations of classification of brain tumors have shown that an accuracy around 90% can be achieved for most of the pairwise discrimination problems. However, the survival rate for patients affected by gliomas is still low. The High-Resolution Magic-Angle-Spinning Nuclear Magnetic Resonance (HR-MAS NMR) metabolomics studies may be helpful for the discrimination of gliomas grades and the development of new strategies for clinical intervention. Here, we propose to use T2 -filtered, diffusion-filtered and conventional water-presaturated spectra to try to extract as much information as possible, fusing the data gathered by these different NMR experiments and applying a chemometric approach based on Multivariate Curve Resolution (MCR). Biomarkers important for glioma's discrimination were found. In particular, we focused our attention on cystathionine (Cyst) that shows promise as a biomarker for the better prognosis of glioma tumors.


Assuntos
Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Glioma/metabolismo , Glioma/patologia , Metabolômica , Adulto , Idoso , Análise Discriminante , Humanos , Análise dos Mínimos Quadrados , Metaboloma , Pessoa de Meia-Idade , Gradação de Tumores , Análise de Componente Principal , Espectroscopia de Prótons por Ressonância Magnética
2.
Sci Rep ; 9(1): 11515, 2019 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-31395965

RESUMO

Actinic keratosis (AK) is a skin premalignant lesion, which progresses into squamous cell carcinoma (SCC) if left untreated. Ingenol mebutate gel is approved for local treatment of non-hyperkeratotic, non-hypertrophic AK; it also has the potential to act as a field cancerization therapy to prevent the progression of AK to SCC. To gain better insights into the mechanisms of ingenol mebutate beyond the mere clinical assessment, we investigated, for the first time, the metabolome of skin tissues from patients with AK, before and after ingenol mebutate treatment, with high-resolution magic angle spinning nuclear magnetic resonance spectroscopy. The metabolomic profiles were compared with those of tissues from healthy volunteers. Overall, we identified a number of metabolites, the homeostasis of which became altered during the process of tumorigenesis from healthy skin to AK, and was restored, at least partially, by ingenol mebutate therapy. These metabolites may help to attain a better understanding of keratinocyte metabolism and to unmask the metabolic pathways related to cell proliferation. These results provide helpful information to identify biomarkers with prognostic and therapeutic significance in AK, and suggest that field cancerization therapy with ingenol mebutate may contribute to restore skin metabolism to a normal state in patients with AK.


Assuntos
Biomarcadores Tumorais/metabolismo , Diterpenos/farmacologia , Ceratose Actínica/tratamento farmacológico , Metabolômica , Pele/metabolismo , Estudos de Casos e Controles , Humanos , Ceratose Actínica/metabolismo , Espectroscopia de Prótons por Ressonância Magnética
3.
Biosci Rep ; 38(3)2018 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-29752335

RESUMO

Molecular motors play relevant roles on the regulation of mitochondria size and shape, essential properties for the cell homeostasis. In this work, we tracked single rod-shaped mitochondria with nanometer precision to explore the performance of microtubule motor teams during processive anterograde and retrograde transport. We analyzed simultaneously the organelle size and verified that mitochondria retracted during retrograde transport with their leading tip moving slower in comparison with the rear tip. In contrast, mitochondria preserved their size during anterograde runs indicating a different performance of plus-end directed teams. These results were interpreted considering the different performance of dynein and kinesin teams and provide valuable information on the collective action of motors during mitochondria transport.


Assuntos
Homeostase/genética , Microtúbulos/genética , Mitocôndrias/genética , Forma das Organelas/genética , Animais , Dineínas/genética , Cinesinas/genética , Microtúbulos/metabolismo , Análise de Célula Única , Xenopus laevis/genética
4.
Biochim Biophys Acta ; 1830(11): 5095-103, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23872153

RESUMO

BACKGROUND: Organelle transport is driven by the action of molecular motors. In this work, we studied the dynamics of organelles of different sizes with the aim of understanding the complex relation between organelle motion and microenvironment. METHODS: We used single particle tracking to obtain trajectories of melanosomes (pigmented organelles in Xenopus laevis melanophores). In response to certain hormones, melanosomes disperse in the cytoplasm or aggregate in the perinuclear region by the combined action of microtubule and actin motors. RESULTS AND CONCLUSIONS: Melanosome trajectories followed an anomalous diffusion model in which the anomalous diffusion exponent (α) provided information regarding the trajectories' topography and thus of the processes causing it. During aggregation, the directionality of big organelles was higher than that of small organelles and did not depend on the presence of either actin or intermediate filaments (IF). Depolymerization of IF significantly reduced α values of small organelles during aggregation but slightly affect their directionality during dispersion. GENERAL SIGNIFICANCE: Our results could be interpreted considering that the number of copies of active motors increases with organelle size. Transport of big organelles was not influenced by actin or IF during aggregation showing that these organelles are moved processively by the collective action of dynein motors. Also, we found that intermediate filaments enhance the directionality of small organelles suggesting that this network keeps organelles close to the tracks allowing their efficient reattachment. The higher directionality of small organelles during dispersion could be explained considering the better performance of kinesin-2 vs. dynein at the single molecule level.


Assuntos
Proteínas Motores Moleculares/metabolismo , Tamanho das Organelas/fisiologia , Organelas/fisiologia , Actinas/metabolismo , Animais , Transporte Biológico , Células Cultivadas , Microambiente Celular/fisiologia , Difusão , Dineínas/metabolismo , Filamentos Intermediários/metabolismo , Melanóforos/metabolismo , Melanóforos/fisiologia , Melanossomas/metabolismo , Melanossomas/fisiologia , Microtúbulos/metabolismo , Microtúbulos/fisiologia , Organelas/metabolismo , Relação Estrutura-Atividade , Xenopus laevis
5.
J Chromatogr A ; 1087(1-2): 265-73, 2005 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-16130723

RESUMO

In this study the investigation of the aroma compounds of dried fruits of Evodia rutaecarpa (Juss.) Benth. and E. rutaecarpa (Juss.) Benth. var. officinalis (Dode) Huang (i.e. E. officinalis Dode) (Rutaceae family) was carried out to identify the odorous target components responsible for the characteristic aroma of these valuable natural products. To avoid the traditional and more time-consuming hydrodistillation, the analyses were carried out by means of headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography-mass spectrometry (GC-MS). The SPME headspace volatiles were collected using a divinylbenzene-carboxen-polydimethylsiloxane (DVB-CAR-PDMS) fiber. The extraction conditions were optimized using a response surface experimental design to analyze the effect of three factors: extraction temperature, equilibrium time and extraction time. The best response was obtained when the extraction temperature was around 80 degrees C, equilibrium time near 25 min and extraction time close to 18 min. Analyses were performed by GC-MS with a 5% diphenyl-95% dimethyl polysiloxane (30 m x 0.25 mm I.D., film thickness 0.25 microm) capillary column using He as the carrier gas and a programmed temperature run. The main components of the HS-SPME samples of E. rutaecarpa (concentration >3.0%) were limonene (33.79%), beta-elemene (10.78%), linalool (8.15%), myrcene (5.83%), valencene (4.73%), beta-caryophyllene (4.62%), linalyl acetate (4.13%) and alpha-terpineol (3.99%). As for E. officinalis, the major compounds were myrcene (32.79%), limonene (18.36%), beta-caryophyllene (9.92%), trans-beta-ocimene (6.04%), linalool (5.88%), beta-elemene (7.85%) and valencene (4.62%).


Assuntos
Evodia/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Volatilização
6.
RBM rev. bras. med ; 57(11): 1306-11, nov. 2000. tab
Artigo em Português | LILACS | ID: lil-283907

RESUMO

Este estudo näo comparativo teve por objetivo avaliara eficácia e tolerabilidade do derivado imidazólico nas vulvovaginites por Candida albicans. A casuística envolveu 46 mulheres entre 19 e 60 anos. Com diagnóstico clínico e micológico de candidíase, selecionadas em dois centros. O tratamento consistiu em aplicaçöestópicas diária de 5 gramas de fenticinazol creme vaginal a 2 porcento durante sete noites consecutivas. A eficácia foi avaliada por um escore de sinais e sintomas e pela evoluçäo do exame micológico em duas visitas: entre os dias 10-14 (V1) e dias 33-44 (V2). A tolerabilidade foi avaliada pelo registro dos edversos relatados durante o período do estudo. Houve reduçäo estatisticamente da intensidade dos sinais e sintomas: ardor, leucorréia, prurido, hiperemia, edema, descamaçäo do epitélio, bem como da soma dosescores associados a eles após o tratamento. Houve reduçäosignificativado número de pacientes que apresentaram Candida e levedura nas culturas da V1 (X21 = 6,67- p<0,05) e V2(X21 = 5,82 - p<0,05). Na V1, 54,3 porcento daspacientes se encontravam sem doença clínica com micológiconegativo e na V2 esta porcentagem subiu para 63,3 porcento das pacientes (X21 = 17,05 - p<0,001). Apenas três pacientes (6,5 porcento) reportaram eventos adversos com o uso de fenticonazol. Em conclusäo, este estudo multicêntrico aberto demonstrou a eficácia do fenticonazol creme vaginal a 2 porcento na candidíase vaginal e sua boa tolerabilidade, sendo adequado para o tratamento de rotina desta afecçäo


Assuntos
Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Antifúngicos/uso terapêutico , Candidíase Vulvovaginal/tratamento farmacológico , Candidíase Vulvovaginal/diagnóstico
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