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BACKGROUND: Electroconvulsive therapy (ECT) is a highly effective brain stimulation treatment for severe depression. Identifying neurochemical changes linked with ECT may point to biomarkers and predictors of successful treatment response. METHODS: We used proton magnetic resonance spectroscopy (1H-MRS) to measure longitudinal changes in glutamate/glutamine (Glx), creatine (Cre), choline (Cho) and N-acetylaspartate (NAA) in the dorsal (dACC) and subgenual anterior cingulate cortex (sgACC) and bilateral hippocampus in patients receiving ECT scanned at baseline, after the second ECT session and after the ECT treatment series. Patients were compared with demographically similar controls at baseline. Controls were assessed twice to establish normative values and variance. RESULTS: We included 50 patients (mean age 43.78 ± 14 yr) and 33 controls (mean age 39.33 ± 12 yr) in our study. Patients underwent a mean of 9 ± 4.1 sessions of ECT. At baseline, patients showed reduced Glx in the sgACC, reduced NAA in the left hippocampus and increased Glx in the left hippocampus relative to controls. ECT was associated with significant increases in Cre in the dACC and sgACC and decreases in NAA in the dACC and right hippocampus. Lower NAA levels in the dACC at baseline predicted reductions in depressive symptoms. Both ECT and symptom improvement were associated with decreased Glx in the left hippocampus and increased Glx in the sgACC. LIMITATIONS: Attrition and clinical heterogeneity may have masked more subtle findings. CONCLUSION: ECT elicits robust effects on brain chemistry, impacting Cre, NAA and Glx, which suggests restorative and neurotrophic processes. Differential effects of Glx in the sgACC and hippocampus, which approach control values with treatment, may reflect previously implicated underactive cortical and overactive subcortical limbic circuitry in patients with major depression. NAA levels at baseline are predictive of therapeutic outcome and could inform future treatment strategies.
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Trastorno Depresivo Mayor/metabolismo , Trastorno Depresivo Mayor/terapia , Terapia Electroconvulsiva , Giro del Cíngulo/metabolismo , Hipocampo/metabolismo , Adulto , Biomarcadores/líquido cefalorraquídeo , Trastorno Bipolar/diagnóstico por imagen , Trastorno Bipolar/metabolismo , Trastorno Bipolar/terapia , Estudios Transversales , Trastorno Depresivo Mayor/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Giro del Cíngulo/diagnóstico por imagen , Hipocampo/diagnóstico por imagen , Humanos , Estudios Longitudinales , Masculino , Espectroscopía de Protones por Resonancia Magnética , Escalas de Valoración Psiquiátrica , Análisis de Regresión , Resultado del TratamientoRESUMEN
ABSTRACT: There is debate on the role of estrogens in modulating the risk for atherosclerosis in women. Our purpose was to investigate whether the size of the estrogenic impact was independently associated with variation of carotid intima-media thickness (IMT) in healthy late postmenopausal women. The levels of circulating estrogens have been used in previous studies but the influence of SNPs of the estrogen receptors (ER) α and ß have not been investigated.We performed a crossed-sectional study of 91 women in a university hospital. We used a double approach in which, in addition to the measurement of estradiol levels by ultrasensitive methods, genetic variants (SNPs) associated with differing expression of the ER α and ß genes were assessed. Multivariable analysis was used to examine the association of candidate factors with the value of IMT and plaque detection at both the carotid wall and the sinus.A genotype combination translating reduced gene expression of the ERß was directly associated with IMT at both the carotid wall (Pâ=â.001) and the sinus (Pâ=â.002). Other predictors of IMT were the levels of glucose, positively associated with IMT at both the carotid wall (Pâ<â.001) and the sinus (Pâ=â.001), age positively associated with IMT at the sinus (Pâ=â.003), and levels of vitamin D, positively associated with IMT at the carotid wall (Pâ=â.04).Poorer estrogenic impact, as concordant with a SNP variant imposing reduced expression of the ERß, was directly associated with IMT at both the carotid wall and the sinus. Glucose level, vitamin D only for the carotid wall, and age only for the sinus, also emerged as independent factors in the IMT variance.
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Grosor Intima-Media Carotídeo/estadística & datos numéricos , Receptor beta de Estrógeno/genética , Posmenopausia , Anciano , Biomarcadores/análisis , Biomarcadores/sangre , Grosor Intima-Media Carotídeo/instrumentación , Estudios Transversales , Receptor beta de Estrógeno/sangre , Femenino , Factores de Riesgo de Enfermedad Cardiaca , Hospitales Universitarios/organización & administración , Hospitales Universitarios/estadística & datos numéricos , Humanos , Modelos Lineales , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple/genética , Factores de Riesgo , Ultrasonografía/métodosRESUMEN
In this paper, we propose a model for denoising and deblurring consisting of a system of linear partial differential equations with locally constant coefficients, obtained as a local linearization of the total variation models. The keypoint of our model is to get the local inversion of the Laplacian operator, which will be done via the Fast Fourier Transform (FFT). Two local schemes will be developed: a pointwise and a piecewise one. We will analyze both, their advantages and their limitations.
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Transient regional osteoporosis (TRO) is a disease that predisposes to fragility fracture in weight bearing joints of mid-life women and men. Pregnant women may also suffer the process, usually at the hip. The prevalence of TRO is lower than the systemic form, associated with postmenopause and advanced age, but may be falsely diminished by under-diagnosis. The disease may be uni- or bilateral, and may migrate to distinct joints. One main feature of TRO is spontaneous recovery. Pain and progressive limitation in the functionality of the affected joint(s) are key symptoms. In the case of the form associated with pregnancy, difficulties in diagnosis derive from the relatively young age at presentation and from the clinical overlapping with the frequent aches during gestation. Densitometric osteoporosis in the affected region is not always present, but bone marrow edema, with or without joint effusion, is detected by magnetic resonance. There are not treatment guidelines, but the association of antiresorptives to symptomatic treatment seems to be beneficial. Surgery or other orthopedic interventions can be required for specific indications, like hip fracture, intra-medullary decompression, or other.
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Artropatías/fisiopatología , Osteoporosis/fisiopatología , Femenino , Humanos , Artropatías/terapia , Masculino , Osteoporosis/terapia , EmbarazoRESUMEN
We present a novel edge preserved interpolation scheme for fast upsampling of natural images. The proposed piecewise hyperbolic operator uses a slope-limiter function that conveniently lends itself to higher-order approximations and is responsible for restricting spatial oscillations arising due to the edges and sharp details in the image. As a consequence the upsampled image not only exhibits enhanced edges, and discontinuities across boundaries, but also preserves smoothly varying features in images. Experimental results show an improvement in the PSNR compared to typical cubic, and spline-based interpolation approaches.
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We propose a novel method for resolution enhancement for volumetric images based on a variational-based reconstruction approach. The reconstruction problem is posed using a deconvolution model that seeks to minimize the total variation norm of the image. Additionally, we propose a new edge-preserving operator that emphasizes and even enhances edges during the up-sampling and decimation of the image. The edge enhanced reconstruction is shown to yield significant improvement in resolution, especially preserving important edges containing anatomical information. This method is demonstrated as an enhancement tool for low-resolution, anisotropic, 3D brain MRI images, as well as a pre-processing step to improve skull-stripping segmentation of brain images.