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1.
J Cent Nerv Syst Dis ; 15: 11795735231195775, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37600237

RESUMO

Background: Changes in brain connectivity occur in patients with multiple sclerosis (MS), even in patients under disease-modifying therapies. Using magnetic resonance imaging (MRI) to asses patients treated with disease-modifying therapies, such as natalizumab, can elucidate the mechanisms involved in clinical deterioration in MS. Objectives: To evaluate differences in resting-state functional connectivity among MS patients treated with natalizumab, MS patients not treated with natalizumab, and controls. Design: Single-center retrospective cross-sectional study. Methods: Twenty-three MS patients being treated with natalizumab were retrospectively compared with 23 MS patients who were naïve for natalizumab, and were using first-line medications (interferon-ß and/or glatiramer acetate), and 17 gender- and age-matched control subjects. The MS patient groups were also matched for time since diagnosis and hyperintense lesion volume on FLAIR. All participants underwent brain MRI using a 3 Tesla scanner. Independent component analysis and dual regression were used to identify resting-state functional connectivity using the FMRIB Software Library. Results: In comparison to controls, the MS patients treated with natalizumab presented decreased connectivity in the left orbitofrontal cortex, in the anterior cingulate and orbitofrontal cortex network. The patients not treated with natalizumab presented increased connectivity in the secondary visual, sensorimotor, and ventral attention networks in comparison to controls.Compared to patients treated with natalizumab, the patients not using natalizumab presented increased connectivity in the left Heschl's gyrus and in the right superior frontal gyrus in the ventral attention network. Conclusion: Differences in brain connectivity between MS patients not treated with natalizumab, healthy controls, and patients treated with natalizumab may be secondary to suboptimal neuronal compensation due to prior less efficient treatments, or due to a compensation in response to maladaptive plasticity.

2.
J Neuroimaging ; 32(4): 690-696, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35191129

RESUMO

BACKGROUND AND PURPOSE: The digiti quinti sign (DQS) consists of a wider angle between the fourth and fifth fingers (ANG) indicative of subtle hemiparesis that has been found interictally in hemiplegic migraine (HM), suggesting a permanent subtle motor dysfunction. The aim of this study was to find a possible cortical origin for the DQS using blood oxygen level dependent (BOLD) functional (f) MRI. METHODS: Eight HM patients and 13 controls entered the cross-sectional study. We examined hand dominance, performed handgrip tests with dynamometry, documented the DQS graphically in two consecutive sessions, and used BOLD-fMRI during a motor task specifically designed to measure the evoked activation in the motor cortex (M1). The brain activation at the symptomatic side was compared with the contralateral hemisphere and with both correspondent hemispheres in controls. RESULTS: Subjects had a normal neurological examination, except for DQS in all HM patients. The activation amplitude (beta values) and the cluster extension (mm3 ) of the activation area in M1 was smaller at the affected side. Besides, the cluster extension correlated negatively with the disease time span. The ANG was wider bilaterally in patients and the fMRI signals were reduced in the patient's group. CONCLUSION: The DQS, a relevant clinical finding in HM, indicates a disrupted cortical activation.


Assuntos
Imageamento por Ressonância Magnética , Enxaqueca com Aura , Estudos Transversais , Força da Mão , Hemiplegia , Humanos , Imageamento por Ressonância Magnética/métodos
3.
Radiol Artif Intell ; 3(4): e200184, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34350408

RESUMO

PURPOSE: To develop a deep learning model for detecting brain abnormalities on MR images. MATERIALS AND METHODS: In this retrospective study, a deep learning approach using T2-weighted fluid-attenuated inversion recovery images was developed to classify brain MRI findings as "likely normal" or "likely abnormal." A convolutional neural network model was trained on a large, heterogeneous dataset collected from two different continents and covering a broad panel of pathologic conditions, including neoplasms, hemorrhages, infarcts, and others. Three datasets were used. Dataset A consisted of 2839 patients, dataset B consisted of 6442 patients, and dataset C consisted of 1489 patients and was only used for testing. Datasets A and B were split into training, validation, and test sets. A total of three models were trained: model A (using only dataset A), model B (using only dataset B), and model A + B (using training datasets from A and B). All three models were tested on subsets from dataset A, dataset B, and dataset C separately. The evaluation was performed by using annotations based on the images, as well as labels based on the radiology reports. RESULTS: Model A trained on dataset A from one institution and tested on dataset C from another institution reached an F1 score of 0.72 (95% CI: 0.70, 0.74) and an area under the receiver operating characteristic curve of 0.78 (95% CI: 0.75, 0.80) when compared with findings from the radiology reports. CONCLUSION: The model shows relatively good performance for differentiating between likely normal and likely abnormal brain examination findings by using data from different institutions.Keywords: MR-Imaging, Head/Neck, Computer Applications-General (Informatics), Convolutional Neural Network (CNN), Deep Learning Algorithms, Machine Learning Algorithms© RSNA, 2021Supplemental material is available for this article.

4.
Radiol Bras ; 53(6): 359-365, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33304002

RESUMO

OBJECTIVE: We aimed to evaluate whether human immunodeficiency virus (HIV)-positive patients with and without clinically significant memory deficits and healthy control participants differ on in vivo hydrogen-1 magnetic resonance spectroscopy (H-MRS) in the posterior cingulate gyri. MATERIALS AND METHODS: In total, 21 HIV-positive patients with memory deficit (HIV+wMD) were compared with 15 HIV-positive patients without memory deficit (HIV+wOMD) and 22 sex-, age-, and education-matched control participants. Memory impairments were classified based on the participants' performance on the Rey Auditory Verbal Learning Test. Short echo time (30 ms), single-voxel H-MRS was performed using a 1.5-T magnetic resonance scanner. RESULTS: The HIV+wMD and HIV+wOMD groups had higher choline/creatine ratio in the posterior cingulate gyri than the control group. There were no significant metabolite ratio differences between the HIV+wMD and HIV+wOMD groups. CONCLUSION: HIV-positive patients with and without memory deficits had significantly higher choline/creatine ratios than controls in the posterior cingulate gyri, which may reflect cerebral inflammation, altered cell membrane metabolism, microgliosis, and/or astrocytosis.


OBJETIVO: Nós avaliamos se os pacientes HIV-positivos com e sem déficits de memória clinicamente significativos e controles saudáveis diferem na espectroscopia de prótons do giro do cíngulo posterior, por ressonância magnética (RM) cerebral. MATERIAIS E MÉTODOS: Vinte e um pacientes HIV-positivos com déficit de memória foram comparados com 15 pacientes HIV-positivos sem déficit de memória e 22 controles, pareados por sexo, idade e escolaridade. As deficiências de memória foram classificadas por meio do desempenho no Teste de Aprendizagem Auditivo-Verbal de Rey. A espectroscopia de prótons foi realizada com tempo de eco curto (30 ms), por voxel único, no giro do cíngulo posterior, utilizando aparelho de RM de 1,5 T. RESULTADOS: Os pacientes HIV-positivos com e sem déficit de memória apresentaram aumento da relação colina/creatina no giro do cíngulo posterior, comparados aos controles. Não houve diferenças significativas nas relações metabólicas no grupo HIV-positivo com déficit de memória, em relação ao grupo de pacientes HIV-positivo sem déficit. CONCLUSÃO: Pacientes HIV-positivos com e sem déficits de memória apresentaram relações colina/creatina significativamente aumentadas em relação aos controles, no giro do cíngulo posterior, o que pode refletir inflamação cerebral, alteração do metabolismo da membrana celular, microgliose e/ou astrocitose.

5.
Neuroradiol J ; 31(6): 587-595, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30091662

RESUMO

PURPOSE: Cognitive dysfunction is common in neuropsychiatric systemic lupus erythematosus (SLE). Memory is a commonly affected cognitive domain. Clinically, however, it is difficult to detect memory deficits. The objective of this study is to evaluate whether normal controls and SLE patients with and without memory deficit differ in terms of white-matter integrity. METHODS: Twenty SLE patients with memory deficit were compared to 47 SLE patients without memory deficit and 22 sex-, age-, and education-matched control individuals. Diffusion tensor imaging (DTI) was performed in a 1.5-Tesla scanner. For tract-based spatial statistics analysis, a white-matter skeleton was created. A permutation-based inference with 5000 permutations with a threshold of p < 0.05 was used to identify abnormalities in fractional anisotropy (FA). The mean diffusivity (MD), radial diffusivity (RD) and axial diffusivity (AD) were also projected onto the mean FA skeleton. RESULTS: Compared to controls, SLE patients with and without memory deficit had decreased FA in: bilateral anterior thalamic radiation, inferior fronto-occipital fasciculus, superior longitudinal fasciculus, uncinate fasciculus, corticospinal tract, genu, and body of the corpus callosum. SLE patients with and without memory deficit also presented increased MD and RD values compared to controls in these areas. Comparison between SLE patients with and without memory deficit did not present significant differences in DTI parameters. CONCLUSION: DTI can detect extensive abnormalities in the normal-appearing white matter of SLE patients with and without memory deficit, compared to controls. However, there was no difference, in terms of white-matter integrity, between the groups of SLE patients.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Lúpus Eritematoso Sistêmico/patologia , Transtornos da Memória/patologia , Substância Branca/diagnóstico por imagem , Adulto , Anisotropia , Mapeamento Encefálico , Estudos de Casos e Controles , Transtornos Cognitivos/diagnóstico por imagem , Transtornos Cognitivos/etiologia , Corpo Caloso/diagnóstico por imagem , Feminino , Humanos , Lúpus Eritematoso Sistêmico/diagnóstico por imagem , Masculino , Transtornos da Memória/diagnóstico por imagem , Pessoa de Meia-Idade , Fibras Nervosas/patologia , Testes Neuropsicológicos , Estudos Retrospectivos
6.
Neuroradiol J ; 31(4): 372-378, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29895218

RESUMO

Purpose Despite antiretroviral therapy, approximately half of individuals with human immunodeficiency virus (HIV) will develop HIV-associated neurocognitive disorder (HAND). Efficiency of brain networks is of great importance for cognitive functioning, since functional networks may reorganize or compensate to preserve normal cognition. This study aims to compare efficiency of the posterior cingulate cortex (PCC) between patients with and without HAND and controls. We hypothesize HAND negative (HAND-) patients will show higher PCC efficiency than HAND positive (HAND+) patients. Methods A total of 10 HAND + patients were compared with 9 HAND- patients and 17 gender-, age-, and education-matched controls. Resting-state functional MRI was acquired with a 3 Tesla scanner. Local efficiency, a measure of network functioning, was investigated for PCC. Network differences among HAND + , HAND- patients and controls were tested as well as correlations between network parameters and cognitive test performance in different domains. Results HAND- patients showed significantly increased PCC efficiency compared with healthy controls ( p = 0.015). No differences were observed between HAND + patients and either controls ( p = 0.327) or HAND- patients ( p = 0.152). In HAND- patients, PCC efficiency was positively related with cognitive performance in the attention/working memory domain ( p = 0.003). Conversely, in HAND + patients, PCC efficiency was negatively correlated with performance in the abstraction/executive domain ( p = 0.002). Conclusion HAND- patients showed a higher level of PCC efficiency compared with healthy subjects, and PCC efficiency was positively related to cognitive performance. These results support the functional reorganization hypothesis, that increased PCC efficiency is a compensation technique to maintain cognitive functioning.


Assuntos
Disfunção Cognitiva/etiologia , Disfunção Cognitiva/fisiopatologia , Giro do Cíngulo/fisiopatologia , Infecções por HIV/fisiopatologia , Infecções por HIV/psicologia , Análise de Variância , Mapeamento Encefálico , Cognição/fisiologia , Disfunção Cognitiva/diagnóstico por imagem , Estudos de Coortes , Estudos Transversais , Feminino , Giro do Cíngulo/diagnóstico por imagem , Infecções por HIV/complicações , Infecções por HIV/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Testes Neuropsicológicos , Descanso
7.
J Neuroradiol ; 45(4): 256-260, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29470996

RESUMO

OBJECTIVE: The aim of our study was to detect functional changes in default-mode network of neuromyelitis optica (NMO) patients using resting-state functional magnetic resonance images and the evaluation of subcortical gray-matter structures volumes. MATERIALS AND METHODS: NMO patients (n=28) and controls patients (n=19) were enrolled. We used the integrated registration and segmentation tool, part of FMRIB's Software Library (FSL) to segment subcortical structures including the thalamus, caudate nucleus, putamen, hippocampus and amygdalae. Resting-state functional magnetic resonance images were post-processed using the Multivariate Exploratory Linear Optimized Decomposition into Independent Components, also part of FSL. Average Z-values extracted from the default-mode network were compared between patients and controls using t-tests (P values <0.05 were considered statistically significant). RESULTS: There were areas of increased synchronization in the default-mode network of patients compared to controls, notably in the precuneus and right hippocampus (corrected P<0.01). The frontal area had decreased synchronization in patients compared to controls (corrected P<0.01). There were no observed differences between patients and controls in subcortical volumes or average Z-values values for default-mode network. CONCLUSION: The hyperactivity of certain default-mode network areas may reflect cortical compensation for subtle structural damage in NMO patients.


Assuntos
Encéfalo/fisiopatologia , Substância Cinzenta/fisiopatologia , Neuromielite Óptica/fisiopatologia , Adolescente , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Vias Neurais/fisiopatologia , Estudos Retrospectivos , Adulto Jovem
8.
Neuroradiol J ; 30(6): 535-545, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29068256

RESUMO

Purpose The objectives of this study were to determine if HIV-infected patients treated with highly active antiretroviral therapy (HAART), without dementia, suffer from longitudinal gray matter (GM) volume loss, changes in white matter (WM) integrity and deterioration in functional connectivity at rest, in an average interval of 30 months. Methods Clinically stable HIV-positive patients (on HAART, CD4 + T lymphocyte > 200 cells/µl, and viral loads <50 copies/µl) were recruited. None of them had HIV-associated dementia. Each patient underwent two scans, performed in a 1.5-T magnetic resonance imaging (MRI) scanner. FreeSurfer was used to perform cortical volumetric reconstruction and segmentation of GM structures. WM integrity was assessed using tract-based spatial statistics to post-process diffusion tensor imaging data, and FMRIB's Software Library tools were used to post-process resting-state functional magnetic resonance imaging (RS-fMRI). Results There were no significant differences in cortical thickness, deep GM volumes, or diffusivity parameters between the scans at the two time points. Five resting-state networks were identified in our patients. In the second MRI, HIV-positive patients presented increased areas of functional connectivity in visual pathways, frontoparietal and cerebellar networks, compared with the first MRI (considering p < 0.05). Conclusions RS-fMRI revealed potentially compensatory longitudinal alterations in the brains of HIV-positive patients, attempting to compensate for brain damage related to the infection.


Assuntos
Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , Infecções por HIV/patologia , Imageamento por Ressonância Magnética/métodos , Substância Branca/patologia , Adulto , Contagem de Linfócito CD4 , Imagem de Tensor de Difusão , Feminino , Substância Cinzenta/patologia , Humanos , Interpretação de Imagem Assistida por Computador , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Carga Viral
9.
Clin Endocrinol (Oxf) ; 82(5): 739-46, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25418156

RESUMO

OBJECTIVES: To determine the dopamine receptor subtype 2 (DR2) mRNA levels and protein expression and to evaluate the effect of adjuvant cabergoline therapy on tumour volume (TV) in patients with postoperative residual nonfunctioning pituitary adenoma (NFPA). METHODS: The mRNA expression was quantified by real-time RT-PCR (TaqMan(®)), and protein expression was evaluated by immunohistochemistry. Tumours were classified according to the percentage of immunostained cells for DR2 as scores 1 (<50% of stained cells) or 2 (≥50%). Cabergoline was started at least 6 months after surgery in nine patients with residual tumours (3 mg/week). The cabergoline effect was prospectively evaluated by magnetic resonance imaging using three-dimensional volume calculation. TV reduction >25% was considered significant. RESULTS: The DR2 mRNA expression was variable but was observed in 100% of the samples (N = 20). DR2 protein expression was also observed in all the tumours (N = 34). Twenty-nine tumours (85%) were classified as score 2. The median DR2 mRNA expression was higher in the tumours classified as score 2 compared with score 1 (P = 0·007). TV reduction with cabergoline therapy was observed in 67% of the patients (6/9). The median TV before and after 6 months of treatment was 1·90 cm(3) (0·61-8·74) and 1·69 cm(3) (0·36-4·20) [P = 0·02], respectively. CONCLUSION: In conclusion, DR2 is expressed in all adenomas and the majority of the patients in this study displayed tumour shrinkage on cabergoline (CAB) therapy. Thus, CAB might be useful in adjuvant therapy in NFPA patients with residual tumours after surgery.


Assuntos
Adenoma/tratamento farmacológico , Adenoma/metabolismo , Ergolinas/uso terapêutico , Neoplasias Hipofisárias/tratamento farmacológico , Neoplasias Hipofisárias/metabolismo , Receptores de Dopamina D2/metabolismo , Adulto , Idoso , Antineoplásicos/uso terapêutico , Cabergolina , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Antígeno Ki-67/metabolismo , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Hipófise/metabolismo , RNA Mensageiro/metabolismo , Resultado do Tratamento
10.
World J Radiol ; 6(6): 374-80, 2014 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-24976938

RESUMO

AIM: To evaluate the impact of computed b = 1400 s/mm(2) (C-b1400) vs measured b = 1400 s/mm(2) (M-b1400) diffusion-weighted images (DWI) on lesion detection rate, image quality and quality of lesion demarcation using a modern 3T-MR system based on a small-field-of-view sequence (sFOV). METHODS: Thirty patients (PSA: 9.5 ± 8.7 ng/mL; 68 ± 12 years) referred for magnetic resonance imaging (MRI) of the prostate were enrolled in this study. All measurements were performed on a 3T MR system. For DWI, a single-shot EPI diffusion sequence (b = 0, 100, 400, 800 s/mm²) was utilized. C-b1400 was calculated voxelwise from the ADC and diffusion images. Additionally, M-b1400 was acquired for evaluation and comparison. Lesion detection rate and maximum lesion diameters were obtained and compared. Image quality and quality of lesion demarcation were rated according to a 5-point Likert-type scale. Ratios of lesion-to-bladder as well as prostate-to-bladder signal intensity (SI) were calculated to estimate the signal-to-noise-ratio (SNR). RESULTS: Twenty-four lesions were detected on M-b1400 images and compared to C-b1400 images. C-b1400 detected three additional cancer suspicious lesions. Overall image quality was rated significantly better and SI ratios were significantly higher on C-b1400 (2.3 ± 0.8 vs 3.1 ± 1.0, P < 0.001; 5.6 ± 1.8 vs 2.8 ± 0.9, P < 0.001). Comparison of lesion size showed no significant differences between C- and M-b1400 (P = 0.22). CONCLUSION: Combination of a high b-value extrapolation and sFOV may contribute to increase diagnostic accuracy of DWI without an increase of acquisition time, which may be useful to guide targeted prostate biopsies and to improve quality of multiparametric MRI (mMRI) especially under economical aspects in a private practice setting.

11.
Alcohol Clin Exp Res ; 38(4): 1126-33, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24256621

RESUMO

BACKGROUND: Alcoholic subjects manifest important deficits in frontal executive function, yet maintain cognitive mental status within normal range. METHODS: This study searched for volumetric measurements of segmented brain structures obtained from magnetic resonance imaging (MRI) that would predict executive functions and cognitive mental status in alcoholic subjects. The frontal assessment battery (FAB) and the Mini-Mental State Examination (MMSE) were applied to alcoholic subjects who underwent MRI. Cortical and subcortical segmentation and corrections were performed using FreeSurfer. Multiple linear regressions analyses having volumetric measures of segmented brain structures as predictors for FAB or MMSE scores as dependent measures were conducted. Sixty alcoholic subjects, 52 males, mean age of 47.2 ± SD 10.4 years, with heavy use of alcohol (mean 284.4 ± SD 275.9 g of alcohol/d) over a long time (mean 32.4 ± SD 11.1 years), showed FAB 11.1 ± SD 3.2 and MMSE of 25.2 ± SD 4.1. RESULTS: Multiple regression analyses having left and right side of each segment as predictors showed that gray matter volumes of rostral middle frontal cortex and cerebellar cortex (p < 0.001), in which only the left side of these structures showed significant partial effects in the full model (p < 0.05), showed to predict FAB performance. They were even more predictive when considered together (p < 0.001), in which both left rostral middle frontal cortex (p < 0.05) and left cerebellar cortex (p < 0.01) predictors had significant partial effects in the full model. None of brain structures was predictive of MMSE performance. CONCLUSIONS: We have concluded that volumetric measurements of left rostral middle frontal and cerebellar cortices seem to be able to predict the frontal executive performance but not the cognitive mental status in alcoholic subjects.


Assuntos
Alcoolismo/diagnóstico , Córtex Cerebelar/patologia , Função Executiva/fisiologia , Lobo Frontal/patologia , Substância Cinzenta/patologia , Adulto , Idoso , Alcoolismo/psicologia , Escalas de Graduação Psiquiátrica Breve , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Valor Preditivo dos Testes , Adulto Jovem
12.
AJR Am J Roentgenol ; 202(1): W34-42, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24370163

RESUMO

OBJECTIVE: The purpose of this article is to discuss classic applications in diffusion-weighted imaging (DWI) in demyelinating disease and progression of DWI in the near future. CONCLUSION: DWI is an advanced technique used in the follow-up of demyelinating disease patients, focusing on the diagnosis of a new lesion before contrast enhancement. With technical advances, diffusion-tensor imaging; new postprocessing techniques, such as tract-based spatial statistics; new ways of calculating diffusion, such as kurtosis; and new applications for DWI and its spectrum are about to arise.


Assuntos
Doenças Desmielinizantes/diagnóstico , Imagem de Difusão por Ressonância Magnética/métodos , Meios de Contraste , Doenças Desmielinizantes/patologia , Diagnóstico Diferencial , Progressão da Doença , Humanos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos
13.
PLoS One ; 8(10): e77406, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24098585

RESUMO

INTRODUCTION: There are few data regarding ZAC1 expression in clinically non-functioning pituitary adenomas (NFPA). Because somatotropinomas and NFPA behave differently with respect to tumor shrinkage during somatostatin analogs (SA) therapy, we sought to compare the ZAC1 and somatostatin receptor (sstr) types 1, 2, 3 and 5 mRNA expression in these two pituitary adenoma subtypes and in normal human pituitaries. METHODS: ZAC1 and SSTR mRNA expression levels were evaluated using real-time RT-PCR (TaqMan) in 20 NFPA and compared with the expression levels in 23 somatotropinomas and five normal pituitaries. The NFPA invasiveness was evaluated using magnetic resonance imaging with Hardy's modified criteria. Ki-67 and p53 were evaluated using immunohistochemistry. RESULTS: A total of 20 patients with NFPA [6 males, median age 56 years (range: 30-78)], 23 with acromegaly [12 males, median age 43 years (range: 24-57)] and five normal pituitaries [4 males, median age 48 years (range: 36-54)] were included. Four of the patients (20%) had Hardy's grade 2 tumors; all of the others had Hardy's grade 3 tumors. The Ki-67 median expression was 2.35 (range: 0.2-9.23), and only four of the tumors (20%) were positive for p53. The ZAC1 mRNA expression was significantly lower in NFPA than in somatotropinomas and in normal pituitaries (p<0.001 for both), as well as the SSTR2 (p=0.001 and 0.01, respectively). The SSTR3 expression was higher in the NFPA than in the somatotropinomas and in the normal pituitaries (p=0.03 and 0.02, respectively). No correlation was found between the ZAC1 mRNA expression and the tumor invasiveness, Ki-67 and p53. CONCLUSION: ZAC1 and SSTR2 are underexpressed and SSTR3 is overexpressed in NFPA compared to those in somatotropinomas and in normal pituitaries, which might explain the lack of tumor shrinkage that is observed in response to commercially available SA therapy in patients with NFPA.


Assuntos
Adenoma/genética , Proteínas de Ciclo Celular/genética , Regulação Neoplásica da Expressão Gênica , Adenoma Hipofisário Secretor de Hormônio do Crescimento/genética , Neoplasias Hipofisárias/genética , Receptores de Somatostatina/genética , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética , Adenoma/tratamento farmacológico , Adenoma/metabolismo , Adenoma/patologia , Adulto , Idoso , Estudos de Casos e Controles , Proteínas de Ciclo Celular/metabolismo , Feminino , Adenoma Hipofisário Secretor de Hormônio do Crescimento/tratamento farmacológico , Adenoma Hipofisário Secretor de Hormônio do Crescimento/metabolismo , Adenoma Hipofisário Secretor de Hormônio do Crescimento/patologia , Humanos , Antígeno Ki-67/genética , Antígeno Ki-67/metabolismo , Masculino , Pessoa de Meia-Idade , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Hipófise/patologia , Neoplasias Hipofisárias/tratamento farmacológico , Neoplasias Hipofisárias/metabolismo , Neoplasias Hipofisárias/patologia , Receptores de Somatostatina/metabolismo , Somatostatina/análogos & derivados , Somatostatina/uso terapêutico , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/metabolismo
14.
Endocr Pract ; 19(6): e145-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23807517

RESUMO

OBJECTIVE: To describe a case of a pure silent somatotroph pituitary carcinoma. METHODS: We describe a 54-year-old female with a clinically nonfunctioning pituitary macroadenoma diagnosed 15 years earlier. RESULTS: The patient underwent transsphenoidal surgery and no visible tumor remnant was observed for 6 years. A magnetic resonance imaging (MRI) detected the recurrence of a 1.2 × 1.5 cm macroadenoma. The patient was submitted to conventional radiotherapy (4500 cGy), and the tumor volume remained stable for 7 years. Then, an MRI revealed a slight increase in tumor size, and 2 years later, a subsequent MRI detected a very large, invasive pituitary mass. The patient was resubmitted to transsphenoidal surgery, and the histopathological examination showed diffuse positivity for growth hormone (GH). The nadir GH level during an oral glucose tolerance test was 0.06 ng/mL, and the pre- and postoperative insulin like growth factor type I (IGF-I) levels were within the normal range. Abdominal, chest, brain, and spine MRI showed multiple small and hypervascular liver and bone lesions suggestive of metastases. Liver biopsy confirmed metastasis of GH-producing pituitary carcinoma. The patient has been treated with temozolomide and zoledronic acid for 7 months and with octreotide long-acting release (LAR) for 4 months. The primary tumor and metastases are stable. CONCLUSION: Despite being an extremely rare event, pituitary carcinoma may develop several years after the successful treatment of even a silent GH-producing pituitary adenoma, which suggests that close long-term follow-up is necessary.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Dacarbazina/análogos & derivados , Adenoma Hipofisário Secretor de Hormônio do Crescimento/tratamento farmacológico , Neoplasias Hipofisárias/tratamento farmacológico , Antineoplásicos Hormonais/uso terapêutico , Neoplasias Ósseas/secundário , Dacarbazina/uso terapêutico , Difosfonatos/uso terapêutico , Feminino , Adenoma Hipofisário Secretor de Hormônio do Crescimento/patologia , Hormônio do Crescimento Humano/sangue , Humanos , Imidazóis/uso terapêutico , Neoplasias Hepáticas/secundário , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Octreotida/uso terapêutico , Neoplasias Hipofisárias/patologia , Temozolomida , Ácido Zoledrônico
15.
Can J Neurol Sci ; 40(3): 284-91, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23603162

RESUMO

This systematic review described the criteria and main evaluations methods procedures used to classify neuropsychiatric systemic lupus erythematosus (NPSLE) patients. Also, within the evaluations methods, this review aimed to identify the main contributions of neuropsychological measurements in neuroimaging studies. A search was conducted in PubMed, EMBASE and SCOPUS databases with the terms related to neuropsychiatric syndromes, systemic lupus erythematosus, and neuroimaging techniques. Sixty-six abstracts were found; only 20 were completely analyzed and included. Results indicated that the 1999 American College of Rheumatology (ACR) criteria is the most used to classify NPSLE samples together with laboratorial, cognitive, neurological and psychiatric assessment procedures. However, the recommended ACR assessment procedures to classify NPSLE patients are being used incompletely, especially the neuropsychological batteries. Neuropsychological instruments and neuroimaging techniques have been used mostly to characterize NPSLE samples, instead of contributing to their classifications. The most described syndromes in neuroimaging studies have been seizure/cerebrovascular disease followed by cognitive dysfunctions as well as headache disorder.


Assuntos
Vasculite Associada ao Lúpus do Sistema Nervoso Central/classificação , Vasculite Associada ao Lúpus do Sistema Nervoso Central/diagnóstico , Neuroimagem , Eletroencefalografia , Humanos , Armazenamento e Recuperação da Informação/estatística & dados numéricos
16.
J Magn Reson Imaging ; 38(6): 1488-93, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23559497

RESUMO

PURPOSE: To evaluate the white matter integrity of the corona radiata, cingulate gyri, and corpus callosum in patients with human immunodeficiency virus (HIV) infection through diffusion tensor imaging (DTI). MATERIALS AND METHODS: Thirty-four patients with at least 5 years of HIV infection and 27 healthy controls underwent magnetic resonance imaging (MRI) in a 1.5 T scanner. A voxelwise-based technique was used to analyze the DTI data. RESULTS: We found that in the body of corpus callosum the fractional anisotropy (FA) was significantly reduced, whereas mean diffusivity (MD) and radial diffusivity (RD) were increased in HIV patients. Analyzing the corona radiata, axial diffusivity (AD) and MD were significantly increased in the left superior region, MD and RD were increased in the left posterior area, and, furthermore, MD was also increased in the right posterior region. No significant abnormalities were found on the cingulate gyri. The white matter damage, related to FA reduction, was associated with increased RD, indicating that demyelization might be the pathophysiological result of this damage. CONCLUSION: Since the DTI can detect abnormalities in the normal-appearing white matter, this technique may play a role as an early marker of HIV disease progression, including clinical manifestations such as cognitive impairment.


Assuntos
Corpo Caloso/patologia , Imagem de Tensor de Difusão/métodos , Giro do Cíngulo/patologia , Infecções por HIV/patologia , Imageamento Tridimensional/métodos , Cápsula Interna/patologia , Fibras Nervosas Mielinizadas/patologia , Adulto , Idoso , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Rev. bras. neurol ; 48(4): 31-44, out.-dez. 2012. tab, ilus
Artigo em Português | LILACS | ID: lil-666937

RESUMO

As demências rapidamente progressivas constituem um grupo heterogêneo de condições clínicas (neurodegenerativas, vasculares, infecciosas, imunomediadas, tóxicas, metabólicas, tumorais, psicogênicas) e cirúrgicas. Avaliação detalhada é imprescindível, devendo ser seguido protocolo extenso constituído por diversas etapas diagnósticas, que compreendem anamnese detalhada, exames clínico e neurológico, e avaliação complementar. É ressaltada a importância da neuroimagem (RM estrutural do cérebro), sendo apresentadas imagens ilustrativas características das principais condições.


Rapidly progressive dementias constitute a heterogeneous group of clinical (neurodegenerative, vascular, infectious, immunomediated, toxic, metabolic, tumoral, psychogenic) and surgical conditions. Detailed evaluation is essential, and an extensive protocol constituted by several diagnostic steps must be followed, which include detailed anamnesis, clinical and neurological examination, and complementary assessment. The importance of neuroimage (structural MRI of the brain) is highlighted, and illustrative images characteristic of the main conditions are presented.


Assuntos
Humanos , Pessoa de Meia-Idade , Idoso , Imageamento por Ressonância Magnética/métodos , Demência/classificação , Demência/diagnóstico , Neuroimagem , Anamnese , Exame Neurológico , Doenças Neurodegenerativas/diagnóstico , Técnicas de Diagnóstico Neurológico
19.
Dement. neuropsychol ; 6(3): 188-191, set. 2012. tab, ilus
Artigo em Inglês | LILACS | ID: lil-652326

RESUMO

Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) is a hereditary cerebral arteriopathy caused by mutations in the Notch-3 gene. The diagnosis is reached by skin biopsy revealing presence of granular osmiophílic material (GOM), and/or by genetic testing for Notch-3. We report a case of a 52-year oldman with recurrent transient ischemic attacks (TIA), migraine, in addition to progressive sensory, motor and cognitive impairment. He was submitted to a neuropsychological assessment with the CERAD (Consortium to Establish a Registry forAlzheimers Disease) battery along with other tests, as well as neuroimaging and genetic analysis for Notch-3, confirming the diagnosis. Executive function, memory, language and important apraxic changes were found. Imaging studies suggested greater involvement in the frontal lobes and deep areas of the brain.


Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) é uma arteriopatia cerebral hereditária causada por mutações no gene Notch-3. O diagnóstico é feito através de biópsia da pele onde se verifica presença de material osmiofílico granular (GOM) e/ou por teste genético para Notch-3. É relatado o caso de um homem de 52 anos, com ataques isquêmicos transitórios (AIT) recorrentes, enxaqueca e comprometimento sensitivo e motor, e cognitivo progressivo. Foi submetido à avaliação neuropsicológica através da bateria CERAD (Consortium to Establisha Registry for Alzheimers Disease) e outros testes, exames de neuroimagem e análise genética para Notch-3, que confirmou o diagnóstico. Foram encontradas alterações em função executiva, memória, linguagem e importante comprometimento apráxico. Exames de imagem sugerem um maior envolvimento dos lobos frontais e áreas profundas do cérebro.


Assuntos
Humanos , Cognição , CADASIL , Neuropsicologia
20.
J Clin Neurosci ; 19(7): 969-74, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22613491

RESUMO

Brain abnormalities in neuromyelitis optica (NMO) have been reported previously, but the pathophysiological mechanism and clinical relevance of these abnormalities are poorly understood. We assessed the prevalence and patterns of brain MRI abnormalities in a Brazilian cohort of patients with NMO. Conventional brain MRI and medical records from 24 Brazilian patients with NMO were retrospectively evaluated. Brain MRI were classified into four subgroups: normal, non-specific lesions, multiple sclerosis (MS)-like lesions, and typical lesions. Brain lesions were detected in 19 patients (79.2%). Fourteen patients (58.3%) had non-specific lesions, three (12.5%) had MS-like lesions, and two (8.3%) had typical lesions. Differences between these subgroups with respect to the Expanded Disability Status Scale (EDSS) scores (p=0.86) were not significant. This study demonstrates a high prevalence of brain abnormalities in Brazilian patients with NMO; however, we did not find a significant relationship between these abnormalities and EDSS scores.


Assuntos
Encéfalo/patologia , Imageamento por Ressonância Magnética , Neuromielite Óptica/diagnóstico , Adolescente , Adulto , Brasil/epidemiologia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuromielite Óptica/epidemiologia , Estudos Retrospectivos , Adulto Jovem
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