Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 33
Filtrar
1.
Alzheimers Dement ; 2024 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-38644660

RESUMEN

BACKGROUND: Cortical microinfarcts (CMI) were attributed to cerebrovascular disease and cerebral amyloid angiopathy (CAA). CAA is frequent in Down syndrome (DS) while hypertension is rare, yet no studies have assessed CMI in DS. METHODS: We included 195 adults with DS, 63 with symptomatic sporadic Alzheimer's disease (AD), and 106 controls with 3T magnetic resonance imaging. We assessed CMI prevalence in each group and CMI association with age, AD clinical continuum, vascular risk factors, vascular neuroimaging findings, amyloid/tau/neurodegeneration biomarkers, and cognition in DS. RESULTS: CMI prevalence was 11.8% in DS, 4.7% in controls, and 17.5% in sporadic AD. In DS, CMI increased in prevalence with age and the AD clinical continuum, was clustered in the parietal lobes, and was associated with lacunes and cortico-subcortical infarcts, but not hemorrhagic lesions. DISCUSSION: In DS, CMI are posteriorly distributed and related to ischemic but not hemorrhagic findings suggesting they might be associated with a specific ischemic CAA phenotype. HIGHLIGHTS: This is the first study to assess cortical microinfarcts (assessed with 3T magnetic resonance imaging) in adults with Down syndrome (DS). We studied the prevalence of cortical microinfarcts in DS and its relationship with age, the Alzheimer's disease (AD) clinical continuum, vascular risk factors, vascular neuroimaging findings, amyloid/tau/neurodegeneration biomarkers, and cognition. The prevalence of cortical microinfarcts was 11.8% in DS and increased with age and along the AD clinical continuum. Cortical microinfarcts were clustered in the parietal lobes, and were associated with lacunes and cortico-subcortical infarcts, but not hemorrhagic lesions. In DS, cortical microinfarcts are posteriorly distributed and related to ischemic but not hemorrhagic findings suggesting they might be associated with a specific ischemic phenotype of cerebral amyloid angiopathy.

2.
Sci Rep ; 14(1): 6287, 2024 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-38491154

RESUMEN

The absence of a natural animal model is one of the main challenges in Alzheimer's disease research. Despite the challenges of using nonhuman primates in studies, these animals can bridge mouse models and humans, as nonhuman primates are phylogenetically closer to humans and can spontaneously develop AD-type pathology. The capuchin monkey, a New World primate, has recently attracted attention due to its skill in creating and using instruments. We analyzed one capuchin brain using structural 7 T MRI and performed a neuropathological evaluation of three animals. Alzheimer-type pathology was found in the two of the capuchins. Widespread ß-amyloid pathology was observed, mainly in focal deposits with variable morphology and a high density of mature plaques. Notably, plaque-associated dystrophic neurites associated with disruption of axonal transport and early cytoskeletal alteration were frequently found. Unlike in other species of New World monkeys, cerebral arterial angiopathy was not the predominant form of ß-amyloid pathology. Additionally, abnormal aggregates of hyperphosphorylated tau, resembling neurofibrillary pathology, were observed in the temporal and frontal cortex. Astrocyte hypertrophy surrounding plaques was found, suggesting a neuroinflammatory response. These findings indicate that aged capuchin monkeys can spontaneously develop Alzheimer-type pathology, indicating that they may be an advantageous animal model for research in Alzheimer's disease.


Asunto(s)
Enfermedad de Alzheimer , Cebinae , Humanos , Animales , Ratones , Anciano , Enfermedad de Alzheimer/patología , Cebus , Haplorrinos , Péptidos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Placa Amiloide/patología , Proteínas tau/metabolismo
3.
Arq Neuropsiquiatr ; 81(5): 433-443, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37257463

RESUMEN

BACKGROUND: Professional soccer athletes are exposed to repetitive head impacts and are at risk of developing chronic traumatic encephalopathy. OBJECTIVE: To evaluate regional brain glucose metabolism (rBGM) and gray matter (GM) volume in retired soccer players (RSPs). METHODS: Male RSPs and age and sex-matched controls prospectively enrolled between 2017 and 2019 underwent neurological and neuropsychological evaluations, brain MRI and [18F]FDG-PET in a 3.0-Tesla PET/MRI scanner. Visual analysis was performed by a blinded neuroradiologist and a blinded nuclear physician. Regional brain glucose metabolism and GM volume were assessed using SPM8 software. Groups were compared using appropriate statistical tests available at SPM8 and R. RESULTS: Nineteen RSPs (median [IQR]: 62 [50-64.5] years old) and 20 controls (60 [48-73] years old) were included. Retired soccer players performed worse on mini-mental state examination, digit span, clock drawing, phonemic and semantic verbal fluency tests, and had reduced rBGM in the left temporal pole (pFDR = 0.008) and the anterior left middle temporal gyrus (pFDR = 0.043). Semantic verbal fluency correlated with rBGM in the right hippocampus, left temporal pole, and posterior left middle temporal gyrus (p ≤ 0.042). Gray matter volume reduction was observed in similar anatomic regions but was less extensive and did not survive correction for multiple comparisons (pFDR ≥ 0.085). Individual [18F]FDG-PET visual analysis revealed seven RSPs with overt hypometabolism in the medial and lateral temporal lobes, frontal lobes, and temporoparietal regions. Retired soccer players had a higher prevalence of septum pellucidum abnormalities on MRI. CONCLUSION: Retired soccer players had reduced rBGM and GM volume in the temporal lobes and septum pellucidum abnormalities, findings possibly related to repetitive head impacts.


ANTECEDENTES: Jogadores profissionais de futebol estão expostos a impactos cranianos repetitivos e ao risco de desenvolver encefalopatia traumática crônica. OBJETIVO: Avaliar o metabolismo glicolítico cerebral regional (MGCr) e o volume de substância cinzenta (vSC) em jogadores de futebol aposentados (JFAs). MéTODOS: Jogadores de futebol aposentados masculinos e controles pareados por idade e sexo foram incluídos prospectivamente entre 2017 e 2019. Foram realizadas avaliações neurológica e neuropsicológica, ressonância magnética (RM) e [18F]FDG-PET cerebrais (3.0-Tesla PET/RM). As imagens foram analisadas visualmente por um neurorradiologista e um médico nuclear cegos ao grupo de cada participante. O metabolismo glicolítico cerebral regional e o vSC foram avaliados através do programa SPM8. Os grupos foram comparados através de testes estatísticos apropriados disponíveis em SPM8 e R, de acordo com a distribuição e o tipo dos dados. RESULTADOS: Dezenove JFAs (mediana [IIQ]: 62 [50­64.5] anos) e 20 controles (60 [48­73] anos) foram incluídos. Os JFAs tiveram pior desempenho no mini-exame do estado mental e nos testes de dígitos, desenho do relógio, fluência verbal e fluência semântica e apresentaram MGCr significativamente reduzido no polo temporal e no giro temporal médio anterior esquerdos. Fluência semântica (animais) apresentou correlação positiva com MGCr no hipocampo direito, no polo temporal esquerdo e no aspecto posterior do giro temporal médio esquerdo. Menor vSC foi observado nas mesmas regiões, porém este achado não sobreviveu à correção para comparações múltiplas. Análise individual do [18F]FDG-PET cerebral revelou sete JFAs com claro hipometabolismo nas faces medial e lateral dos lobos temporais, nos lobos frontais e nas regiões temporoparietais. Os JFAs apresentaram ainda maior prevalência de anormalidades do septo pelúcido. CONCLUSãO: Os JFAs apresentam MGCr e vSC reduzidos nos lobos temporais, além de anormalidades do septo pelúcido, achados possivelmente relacionados a impactos cranianos repetitivos.


Asunto(s)
Sustancia Gris , Fútbol , Humanos , Masculino , Persona de Mediana Edad , Anciano , Sustancia Gris/diagnóstico por imagen , Fluorodesoxiglucosa F18/metabolismo , Glucosa , Estudios Transversales , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Imagen por Resonancia Magnética , Tomografía de Emisión de Positrones
4.
Arq. neuropsiquiatr ; 81(5): 433-443, May 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1447405

RESUMEN

Abstract Background Professional soccer athletes are exposed to repetitive head impacts and are at risk of developing chronic traumatic encephalopathy. Objective To evaluate regional brain glucose metabolism (rBGM) and gray matter (GM) volume in retired soccer players (RSPs). Methods Male RSPs and age and sex-matched controls prospectively enrolled between 2017 and 2019 underwent neurological and neuropsychological evaluations, brain MRI and [18F]FDG-PET in a 3.0-Tesla PET/MRI scanner. Visual analysis was performed by a blinded neuroradiologist and a blinded nuclear physician. Regional brain glucose metabolism and GM volume were assessed using SPM8 software. Groups were compared using appropriate statistical tests available at SPM8 and R. Results Nineteen RSPs (median [IQR]: 62 [50-64.5] years old) and 20 controls (60 [48-73] years old) were included. Retired soccer players performed worse on mini-mental state examination, digit span, clock drawing, phonemic and semantic verbal fluency tests, and had reduced rBGM in the left temporal pole (pFDR = 0.008) and the anterior left middle temporal gyrus (pFDR = 0.043). Semantic verbal fluency correlated with rBGM in the right hippocampus, left temporal pole, and posterior left middle temporal gyrus (p ≤ 0.042). Cray matter volume reduction was observed in similar anatomic regions but was less extensive and did not survive correction for multiple comparisons (pFDR ≥ 0.085). Individual [18F]FDG-PET visual analysis revealed seven RSPs with overt hypometabolism in the medial and lateral temporal lobes, frontal lobes, and temporoparietal regions. Retired soccer players had a higher prevalence of septum pellucidum abnormalities on MRI. Conclusion Retired soccer players had reduced rBCM and CM volume in the temporal lobes and septum pellucidum abnormalities, findings possibly related to repetitive head impacts.


Resumo Antecedentes Jogadores profissionais de futebol estão expostos a impactos cranianos repetitivos e ao risco de desenvolver encefalopatia traumática crônica. Objetivo Avaliar o metabolismo glicolítico cerebral regional (MCCr) e o volume de substância cinzenta (vSC) em jogadores de futebol aposentados (JFAs). Métodos Jogadores de futebol aposentados masculinos e controles pareados por idade e sexo foram incluídos prospectivamente entre 2017 e 2019. Foram realizadas avaliações neurológica e neuropsicológica, ressonância magnética (RM) e [18F]FDG-PET cerebrais (3.0-Tesla PET/RM). As imagens foram analisadas visualmente por um neurorradiologista e um médico nuclear cegos ao grupo de cada participante. O metabolismo glicolítico cerebral regional e o vSC foram avaliados através do programa SPM8. Os grupos foram comparados através de testes estatísticos apropriados disponíveis em SPM8 e R, de acordo com a distribuição e o tipo dos dados. Resultados Dezenove JFAs (mediana [IIQ]: 62 [50-64.5] anos) e 20 controles (60 [48-73] anos) foram incluídos. Os JFAs tiveram pior desempenho no mini-exame do estado mental e nos testes de dígitos, desenho do relógio, fluência verbal e fluência semântica e apresentaram MCCr significativamente reduzido no polo temporal e no giro temporal médio anterior esquerdos. Fluência semântica (animais) apresentou correlação positiva com MCCr no hipocampo direito, no polo temporal esquerdo e no aspecto posterior do giro temporal médio esquerdo. Menor vSC foi observado nas mesmas regiões, porém este achado não sobreviveu à correção para comparações múltiplas. Análise individual do [18F]FDG-PET cerebral revelou sete JFAs com claro hipometabolismo nas faces medial e lateral dos lobos temporais, nos lobos frontais e nas regiões temporoparietais. Os JFAs apresentaram ainda maior prevalência de anormalidades do septo pelúcido. Conclusão Os JFAs apresentam MCCr e vSC reduzidos nos lobos temporais, além de anormalidades do septo pelúcido, achados possivelmente relacionados a impactos cranianos repetitivos.

6.
Radiographics ; 41(5): 1509-1530, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34415807

RESUMEN

Benign prostatic hyperplasia (BPH) is a noncancerous growth of the transitional zone of the prostate, which surrounds the prostatic urethra. Consequently, it can cause lower urinary tract symptoms (LUTS) and bladder outlet obstruction symptoms that may substantially reduce a patient's quality of life. Several treatments are available for BPH, including medications such as α-blockers and 5α-reductase inhibitors and surgical options including transurethral resection of the prostate and prostatectomy. Recently, prostatic artery embolization (PAE) has emerged as a minimally invasive treatment option for selected men with BPH and moderate to severe LUTS. Adequate pre- and postprocedural evaluations with clinical examinations and questionnaires, laboratory tests, and urodynamic and imaging examinations (particularly US, MRI, and CT) are of key importance to achieve successful treatment. Considering that the use of PAE has been increasing in tertiary hospital facilities, radiologists and interventional radiologists should be aware of the main technical concepts of PAE and the key features to address in imaging reports in pre- and postprocedural settings. An invited commentary by Lopera is available online. Online supplemental material is available for this article. ©RSNA, 2021.


Asunto(s)
Embolización Terapéutica , Hiperplasia Prostática , Resección Transuretral de la Próstata , Arterias , Humanos , Masculino , Hiperplasia Prostática/complicaciones , Hiperplasia Prostática/diagnóstico por imagen , Hiperplasia Prostática/terapia , Calidad de Vida , Resultado del Tratamiento
7.
Brain Inj ; 35(3): 275-284, 2021 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-33507820

RESUMEN

Objective: The goal is to evaluate longitudinally with diffusion tensor imaging (DTI) the integrity of cerebral white matter in patients with moderate and severe DAI and to correlate the DTI findings with cognitive deficits.Methods: Patients with DAI (n = 20) were scanned at three timepoints (2, 6 and 12 months) after trauma. A healthy control group (n = 20) was evaluated once with the same high-field MRI scanner. The corpus callosum (CC) and the bilateral superior longitudinal fascicles (SLFs) were assessed by deterministic tractography with ExploreDTI. A neuropschychological evaluation was also performed.Results: The CC and both SLFs demonstrated various microstructural abnormalities in between-groups comparisons. All DTI parameters demonstrated changes across time in the body of the CC, while FA (fractional anisotropy) increases were seen on both SLFs. In the splenium of the CC, progressive changes in the mean diffusivity (MD) and axial diffusivity (AD) were also observed. There was an improvement in attention and memory along time. Remarkably, DTI parameters demonstrated several correlations with the cognitive domains.Conclusions: Our findings suggest that microstructural changes in the white matter are dynamic and may be detectable by DTI throughout the first year after trauma. Likewise, patients also demonstrated improvement in some cognitive skills.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Lesión Axonal Difusa , Sustancia Blanca , Anisotropía , Encéfalo , Cognición , Lesión Axonal Difusa/diagnóstico por imagen , Imagen de Difusión Tensora , Humanos , Sustancia Blanca/diagnóstico por imagen
9.
Neuroimage Clin ; 17: 628-641, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29234599

RESUMEN

BACKGROUND: Machine learning techniques such as support vector machine (SVM) have been applied recently in order to accurately classify individuals with neuropsychiatric disorders such as Alzheimer's disease (AD) based on neuroimaging data. However, the multivariate nature of the SVM approach often precludes the identification of the brain regions that contribute most to classification accuracy. Multiple kernel learning (MKL) is a sparse machine learning method that allows the identification of the most relevant sources for the classification. By parcelating the brain into regions of interest (ROI) it is possible to use each ROI as a source to MKL (ROI-MKL). METHODS: We applied MKL to multimodal neuroimaging data in order to: 1) compare the diagnostic performance of ROI-MKL and whole-brain SVM in discriminating patients with AD from demographically matched healthy controls and 2) identify the most relevant brain regions to the classification. We used two atlases (AAL and Brodmann's) to parcelate the brain into ROIs and applied ROI-MKL to structural (T1) MRI, 18F-FDG-PET and regional cerebral blood flow SPECT (rCBF-SPECT) data acquired from the same subjects (20 patients with early AD and 18 controls). In ROI-MKL, each ROI received a weight (ROI-weight) that indicated the region's relevance to the classification. For each ROI, we also calculated whether there was a predominance of voxels indicating decreased or increased regional activity (for 18F-FDG-PET and rCBF-SPECT) or volume (for T1-MRI) in AD patients. RESULTS: Compared to whole-brain SVM, the ROI-MKL approach resulted in better accuracies (with either atlas) for classification using 18F-FDG-PET (92.5% accuracy for ROI-MKL versus 84% for whole-brain), but not when using rCBF-SPECT or T1-MRI. Although several cortical and subcortical regions contributed to discrimination, high ROI-weights and predominance of hypometabolism and atrophy were identified specially in medial parietal and temporo-limbic cortical regions. Also, the weight of discrimination due to a pattern of increased voxel-weight values in AD individuals was surprisingly high (ranging from approximately 20% to 40% depending on the imaging modality), located mainly in primary sensorimotor and visual cortices and subcortical nuclei. CONCLUSION: The MKL-ROI approach highlights the high discriminative weight of a subset of brain regions of known relevance to AD, the selection of which contributes to increased classification accuracy when applied to 18F-FDG-PET data. Moreover, the MKL-ROI approach demonstrates that brain regions typically spared in mild stages of AD also contribute substantially in the individual discrimination of AD patients from controls.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico por imagen , Mapeo Encefálico/métodos , Encéfalo/diagnóstico por imagen , Anciano , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/fisiopatología , Atlas como Asunto , Encéfalo/patología , Encéfalo/fisiopatología , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Tomografía de Emisión de Positrones/métodos , Curva ROC , Reproducibilidad de los Resultados , Máquina de Vectores de Soporte , Tomografía Computarizada de Emisión de Fotón Único/métodos
10.
Cardiovasc Intervent Radiol ; 39(2): 299-303, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26126580

RESUMEN

A giant cell tumor (GCT) is an intermediate grade, locally aggressive neoplasia. Despite advances in surgical and clinical treatments, cases located on the spine and pelvic bones remain a significant challenge. Failure of clinical treatment with denosumab and patient refusal of surgical procedures (hemipelvectomy) led to the use of cryoablation. We report the use of percutaneous CT-guided cryoablation as an alternative treatment, shown to be a minimally invasive, safe, and effective option for a GCT with extensive involvement of the pelvic bones and allowed structural and functional preservation of the involved bones.


Asunto(s)
Neoplasias Óseas/patología , Neoplasias Óseas/cirugía , Criocirugía/métodos , Tumores de Células Gigantes/patología , Tumores de Células Gigantes/cirugía , Huesos Pélvicos/patología , Radiografía Intervencional , Tomografía Computarizada por Rayos X , Biopsia , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad
11.
Psychiatry Res ; 234(2): 188-93, 2015 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-26459073

RESUMEN

Bipolar disorder (BD) is highly heritable. First-degree relatives of BD patient have an increased risk to develop the disease. We investigated abnormalities in gray matter (GM) volumes in healthy first-degree relatives of BD patients to identify possible brain structural endophenotypes for the disorder. 3D T1-weighted magnetic resonance images were obtained from 25 DSM-IV BD type I patients, 23 unaffected relatives, and 27 healthy controls (HC). A voxel-based morphometry protocol was used to compare differences in GM volumes between groups. BD patients presented reduced GM volumes bilaterally in the thalamus compared with HC. Relatives presented no global or regional GM differences compared with HC. Our negative results do not support the role of GM volume abnormalities as endophenotypes for BD. Thalamic volume abnormalities may be associated the pathophysiology of the disease.


Asunto(s)
Trastorno Bipolar/diagnóstico , Trastorno Bipolar/genética , Familia , Sustancia Gris/patología , Adulto , Encéfalo/patología , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Endofenotipos , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Adulto Joven
12.
Neuroophthalmology ; 39(6): 285-288, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27928371

RESUMEN

A 44-year-old man presented with severe right visual loss. The right fundus examination showed marked optic disc oedema associated with partial macular star. Serological blood tests for infectious agents were all negative. Serum aquaporin-4 antibody was negative but anti-MOG (myelin oligodendrocyte glycoprotein) was positive. Magnetic resonance revealed extensive lesion in right optic nerve. There was no visual improvement after intravenous therapy. Patient had no further attacks after follow-up. Optic disc oedema with macular star is found in several infectious and non-inflammatory disorders, but it has not been reported in optic neuritis (ON) associated with autoantibodies to myelin oligodendrocyte glycoprotein (anti-MOG).

13.
Arq Neuropsiquiatr ; 72(8): 625-32, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25098479

RESUMEN

Leukodystrophies are genetically determined white matter disorders. Even though leukodystrophies essentially affect children in early infancy and childhood, these disorders may affect adults. In adults, leukodystrophies may present a distinct clinical and imaging presentation other than those found in childhood. Clinical awareness of late-onset leukodystrophies should be increased as new therapies emerge. MRI is a useful tool to evaluate white matter disorders and some characteristics findings can help the diagnosis of leukodystrophies. This review article briefly describes the imaging characteristics of the most common adult leukodystrophies.


Asunto(s)
Enfermedades Desmielinizantes del Sistema Nervioso Central Hereditarias/diagnóstico , Imagen por Resonancia Magnética , Adulto , Enfermedades Desmielinizantes del Sistema Nervioso Central Hereditarias/clasificación , Humanos , Aumento de la Imagen , Masculino , Persona de Mediana Edad
14.
Arq. neuropsiquiatr ; 72(8): 625-632, 08/2014. graf
Artículo en Inglés | LILACS | ID: lil-718114

RESUMEN

Leukodystrophies are genetically determined white matter disorders. Even though leukodystrophies essentially affect children in early infancy and childhood, these disorders may affect adults. In adults, leukodystrophies may present a distinct clinical and imaging presentation other than those found in childhood. Clinical awareness of late-onset leukodystrophies should be increased as new therapies emerge. MRI is a useful tool to evaluate white matter disorders and some characteristics findings can help the diagnosis of leukodystrophies. This review article briefly describes the imaging characteristics of the most common adult leukodystrophies.


Leucodistrofias são doenças geneticamente determinadas. Apesar das leucodistrofias afetarem principalmente crianças lactentes e infantes, estas doenças podem acometer a faixa etária adulta. Nos adultos, as leucodistrofias podem ter uma apresentação clínica e de imagem distinta daquela da infância. Um aumento na suspeita clínica de leucodistrofias com início tardio deve ocorrer associado ao aparecimento de novas alternativas terapêuticas. Este artigo de revisão descreve sumariamente as características de imagem nas leucodistrofias no adulto.


Asunto(s)
Humanos , Masculino , Adulto , Persona de Mediana Edad , Imagen por Resonancia Magnética , Enfermedades Desmielinizantes del Sistema Nervioso Central Hereditarias/diagnóstico , Aumento de la Imagen , Enfermedades Desmielinizantes del Sistema Nervioso Central Hereditarias/clasificación
15.
Brain Dev ; 36(10): 899-906, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24485900

RESUMEN

INTRODUCTION: Neuroimaging studies demonstrate that not only the lesions of malformations of cortical development (MCD) but also the normal-appearing parenchyma (NAP) present metabolic impairments, as revealed with (1)H-MRS. We have previously detected biochemical disturbances in MCD lesions with phosphorus-31 magnetic resonance spectroscopy (31P-MRS). Our hypothesis is that pH abnormalities extend beyond the visible lesions. METHODS: Three-dimensional 31P-MRS at 3.0 T was performed in 37 patients with epilepsy and MCD, and in 31 matched-control subjects. The patients were assigned into three main MCD subgroups: cortical dysplasia (n=10); heterotopia (n=14); schizencephaly/polymicrogyria (n=13). Voxels (12.5 cm3) were selected in five homologous regions containing NAP: right putamen; left putamen; frontoparietal parasagittal cortex; right centrum semiovale; and left centrum semiovale. Robust methods of quantification were applied, and the intracellular pH was calculated with the chemical shifts of inorganic phosphate (Pi) relative to phosphocreatine (PCr). RESULTS: In comparison to controls and considering a Bonferroni adjusted p-value <0.01, MCD patients presented significant reduction in intracellular pH in the frontoparietal parasagittal cortex (6.985±0.022), right centrum semiovale (7.004±0.029), and left centrum semiovale (6.995±0.030), compared to controls (mean values±standard deviations of 7.087±0.048, 7.096±0.042, 7.088±0.045, respectively). Dunnet and Dunn tests demonstrated that the differences in pH values remained statistically significant in all MCD subgroups. No significant differences were found for the putamina. CONCLUSION: The present study demonstrates widespread acidosis in the NAP, and reinforces the idea that MCD visible lesions are only the tip of the iceberg.


Asunto(s)
Encéfalo/metabolismo , Epilepsia/complicaciones , Epilepsia/patología , Espectroscopía de Resonancia Magnética , Malformaciones del Desarrollo Cortical/complicaciones , Malformaciones del Desarrollo Cortical/patología , Adulto , Análisis de Varianza , Encéfalo/patología , Estudios de Casos y Controles , Femenino , Humanos , Concentración de Iones de Hidrógeno , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Fosfocreatina/metabolismo , Fósforo , Adulto Joven
18.
PLoS One ; 7(7): e39528, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22815709

RESUMEN

The aim of this study was to evaluate the effect of Gd-chelate on renal function, iron parameters and oxidative stress in rats with CRF and a possible protective effect of the antioxidant N-Acetylcysteine (NAC). Male Wistar rats were submitted to 5/6 nephrectomy (Nx) to induced CRF. An ionic-cyclic Gd (Gadoterate Meglumine) was administrated (1.5 mM/KgBW, intravenously) 21 days after Nx. Clearance studies were performed in 4 groups of anesthetized animals 48 hours following Gd- chelate administration: 1--Nx (n = 7); 2--Nx+NAC (n = 6); 3--Nx+Gd (n = 7); 4--Nx+NAC+Gd (4.8 g/L in drinking water), initiated 2 days before Gd-chelate administration and maintained during 4 days (n = 6). This group was compared with a control. We measured glomerular filtration rate, GFR (inulin clearance, ml/min/kg BW), proteinuria (mg/24 hs), serum iron (µg/dL); serum ferritin (ng/mL); transferrin saturation (%), TIBC (µg/dL) and TBARS (nmles/ml). Normal rats treated with the same dose of Gd-chelate presented similar GFR and proteinuria when compared with normal controls, indicating that at this dose Gd-chelate is not nephrotoxic to normal rats. Gd-chelate administration to Nx-rats results in a decrease of GFR and increased proteinuria associated with a decrease in TIBC, elevation of ferritin serum levels, transferrin oversaturation and plasmatic TBARS compared with Nx-rats. The prophylactic treatment with NAC reversed the decrease in GFR and the increase in proteinuria and all alterations in iron parameters and TBARS induced by Gd-chelate. NAC administration to Nx rat did not modify the inulin clearance and iron kinetics, indicating that the ameliorating effect of NAC was specific to Gd-chelate. These results suggest that NAC can prevent Gd-chelate nephrotoxicity in patients with chronic renal failure.


Asunto(s)
Acetilcisteína/farmacología , Quelantes/toxicidad , Gadolinio/química , Fallo Renal Crónico/metabolismo , Fallo Renal Crónico/fisiopatología , Riñón/efectos de los fármacos , Animales , Quelantes/química , Tasa de Filtración Glomerular , Inulina/farmacocinética , Riñón/metabolismo , Riñón/fisiopatología , Masculino , Ratas , Ratas Wistar , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo
20.
World J Biol Psychiatry ; 12(7): 539-48, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21486107

RESUMEN

OBJECTIVE: Little is known about the relevance of lesion in neural circuits reported to be associated with major depressive disorder. We investigated the association between lesion stroke size in the limbic-cortical-striatal-pallidal-thalamic (LCSPT) circuit and incidence of major depressive episode (MDE). METHODS: We enrolled 68 patients with first-ever ischemic stroke and no history of major depressive disorder. Neurological and psychiatric examinations were performed at three time-points. We diagnosed major depressive episode, following DSM-IV criteria. Lesion location and volume were determined with magnetic resonance imaging, using a semi-automated method based on the Brodmann Cytoarchitectonic Atlas. RESULTS: Twenty-one patients (31%) experienced major depressive episode. Larger lesions in the left cortical regions of the LCSPT circuit (3,760 vs. 660 mm3; P = 0.004) were associated with higher incidence of MDE. Secondary analyses revealed that major depressive episode was associated with larger lesions in areas of the medial prefrontal cortex including the ventral (BA24) and dorsal anterior cingulate cortex (BA32) and subgenual cortex (BA25); and also the subiculum (BA28/36) and amygdala (BA34). CONCLUSIONS: Our findings indicate that depression due to stroke is aetiologically related to the disruption of the left LCSPT circuit and support the relevance of the medial prefrontal cortex dysfunction in the pathophysiology of depression.


Asunto(s)
Trastorno Depresivo Mayor/etiología , Red Nerviosa/patología , Accidente Cerebrovascular/patología , Adulto , Anciano , Isquemia Encefálica/complicaciones , Isquemia Encefálica/patología , Isquemia Encefálica/fisiopatología , Trastorno Depresivo Mayor/diagnóstico , Trastorno Depresivo Mayor/fisiopatología , Femenino , Humanos , Incidencia , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Red Nerviosa/fisiopatología , Pruebas Neuropsicológicas , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Método Simple Ciego , Accidente Cerebrovascular/complicaciones , Factores de Tiempo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA