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1.
Childs Nerv Syst ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647660

RESUMO

PURPOSE: We studied a pediatric group of patients with sellar-suprasellar tumors, aiming to develop a convolutional deep learning algorithm for radiological assistance to classify them into their respective cohort. METHODS: T1w and T2w preoperative magnetic resonance images of 226 Chilean patients were collected at the Institute of Neurosurgery Dr. Alfonso Asenjo (INCA), which were divided into three classes: healthy control (68 subjects), craniopharyngioma (58 subjects) and differential sellar/suprasellar tumors (100 subjects). RESULTS: The PPV among classes was 0.828±0.039, and the NPV was 0.919±0.063. Also explainable artificial intelligence (XAI) was used, finding that structures that are relevant during diagnosis and radiological evaluation highly influence the decision-making process of the machine. CONCLUSION: This is the first experience of this kind of study in our institution, and it led to promising results on the task of radiological diagnostic support based on explainable artificial intelligence (AI) and deep learning models.

2.
J Alzheimers Dis ; 92(1): 153-169, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36710684

RESUMO

BACKGROUND: Although social cognition is compromised in patients with neurodegenerative disorders such as behavioral variant frontotemporal dementia (bvFTD) and Alzheimer's disease (AD), research on moral emotions and their neural correlates in these populations is scarce. No previous study has explored the utility of moral emotions, compared to and in combination with classical general cognitive state tools, to discriminate bvFTD from AD patients. OBJECTIVE: To examine self-conscious (guilt and embarrassment) and other-oriented (pity and indignation) moral emotions, their subjective experience, and their structural brain underpinnings in bvFTD (n = 31) and AD (n = 30) patients, compared to healthy controls (n = 37). We also explored the potential utility of moral emotions measures to discriminate bvFTD from AD. METHODS: We used a modified version of the Moral Sentiment Task measuring the participants' accuracy scores and their emotional subjective experiences. RESULTS: bvFTD patients exhibited greater impairments in self-conscious and other-oriented moral emotions as compared with AD patients and healthy controls. Moral emotions combined with general cognitive state tools emerged as useful measures to discriminate bvFTD from AD patients. In bvFTD patients, lower moral emotions scores were associated with lower gray matter volumes in caudate nucleus and inferior and middle temporal gyri. In AD, these scores were associated with lower gray matter volumes in superior and middle frontal gyri, middle temporal gyrus, inferior parietal lobule and supramarginal gyrus. CONCLUSION: These findings contribute to a better understanding of moral emotion deficits across neurodegenerative disorders, highlighting the potential benefits of integrating this domain into the clinical assessment.


Assuntos
Doença de Alzheimer , Demência Frontotemporal , Humanos , Testes Neuropsicológicos , Encéfalo , Emoções , Princípios Morais , Doença de Alzheimer/psicologia , Demência Frontotemporal/psicologia , Imageamento por Ressonância Magnética
3.
Neurol Genet ; 7(2): e559, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33977142

RESUMO

OBJECTIVE: Leukoencephalopathy with brainstem and spinal cord involvement and lactate elevation (LBSL) is regarded a relatively mild leukodystrophy, diagnosed by characteristic long tract abnormalities on MRI and biallelic variants in DARS2, encoding mitochondrial aspartyl-tRNA synthetase (mtAspRS). DARS2 variants in LBSL are almost invariably compound heterozygous; in 95% of cases, 1 is a leaky splice site variant in intron 2. A few severely affected patients, still fulfilling the MRI criteria, have been described. We noticed highly unusual MRI presentations in 15 cases diagnosed by WES. We examined these cases to determine whether they represent consistent novel LBSL phenotypes. METHODS: We reviewed clinical features, MRI abnormalities, and gene variants and investigated the variants' impact on mtAspRS structure and mitochondrial function. RESULTS: We found 2 MRI phenotypes: early severe cerebral hypoplasia/atrophy (9 patients, group 1) and white matter abnormalities without long tract involvement (6 patients, group 2). With antenatal onset, microcephaly, and arrested development, group 1 patients were most severely affected. DARS2 variants were severer than for classic LBSL and severer for group 1 than group 2. All missense variants hit mtAspRS regions involved in tRNAAsp binding, aspartyl-adenosine-5'-monophosphate binding, and/or homodimerization. Missense variants expressed in the yeast DARS2 ortholog showed severely affected mitochondrial function. CONCLUSIONS: DARS2 variants are associated with highly heterogeneous phenotypes. New MRI presentations are profound cerebral hypoplasia/atrophy and white matter abnormalities without long tract involvement. Our findings have implications for diagnosis and understanding disease mechanisms, pointing at dominant neuronal/axonal involvement in severe cases. In line with this conclusion, activation of biallelic DARS2 null alleles in conditional transgenic mice leads to massive neuronal apoptosis.

4.
Epilepsy Behav ; 102: 106684, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31778880

RESUMO

Focal cortical dysplasias (FCDs) are a frequent cause of epilepsy. It has been reported that up to 40% of them cannot be visualized with conventional magnetic resonance imaging (MRI). The main objective of this work was to evaluate by means of a retrospective descriptive observational study whether the automated brain segmentation is useful for detecting FCD. One hundred and fifty-five patients, who underwent surgery between the years 2009 and 2016, were reviewed. Twenty patients with FCD confirmed by histology and a preoperative segmentation study, with ages ranging from 3 to 43 years (14 men), were analyzed. Three expert neuroradiologists visually analyzed conventional and advanced MRI with automated segmentation. They were classified into positive and negative concerning visualization of FCD by consensus. Of the 20 patients evaluated with conventional MRI, 12 were positive for FCD. Of the negative studies for FCD with conventional MRI, 2 (25%) were positive when they were analyzed with automated segmentation. In 13 of the 20 patients (with positive segmentation for FCD), cortical thickening was observed in 5 (38.5%), while pseudothickening was observed in the rest of patients (8, 61.5%) in the anatomical region of the brain corresponding to the dysplasia. This work demonstrated that automated brain segmentation helps to increase detection of FCDs that are unable to be visualized in conventional MRI images.


Assuntos
Encéfalo/diagnóstico por imagem , Epilepsia/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Malformações do Desenvolvimento Cortical/diagnóstico por imagem , Adolescente , Adulto , Encéfalo/patologia , Encéfalo/cirurgia , Criança , Pré-Escolar , Epilepsia/patologia , Epilepsia/cirurgia , Feminino , Humanos , Imageamento por Ressonância Magnética/normas , Masculino , Malformações do Desenvolvimento Cortical/patologia , Malformações do Desenvolvimento Cortical/cirurgia , Estudos Retrospectivos , Adulto Jovem
5.
Eur J Paediatr Neurol ; 19(5): 497-503, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26008863

RESUMO

BACKGROUND: Pyruvate dehydrogenase (PDH) deficiency is a disorder of energy metabolism with variable clinical presentations, ranging from severe infantile lactic acidosis to milder chronic neurological disorders. The spectrum of clinical manifestations is continuously expanding. METHODS AND RESULTS: We report on a 19-year-old intelligent female with PDH deficiency caused by a Leu216Ser mutation in PDHA1. She presented with recurrent hemidystonic attacks, triggered by prolonged walking or running, as the unique clinical manifestation that manifested since childhood. Laboratory workup and neuroimages were initially normal but bilateral globus pallidum involvement appeared later on brain MRI. Dystonia completely remitted after high doses of thiamine, remaining free of symptoms after 3 years of follow up. We reviewed the literature for similar observations. CONCLUSIONS: Dystonia precipitated by exercise may be the only symptom of a PDH deficiency, and the hallmark of the disease as high serum lactate or bilateral striatal necrosis at neuroimaging may be absent. A high index of suspicion and follow up is necessary for diagnosis. The clinical presentation of this patient meets the criteria for a Paroxysmal Exercise induced Dystonia, leading us to add this entity as another potential etiology for this type of paroxysmal dyskinesia, which is besides a treatable condition that responds to thiamine supplementation.


Assuntos
Suplementos Nutricionais , Distúrbios Distônicos/etiologia , Doença da Deficiência do Complexo de Piruvato Desidrogenase/complicações , Doença da Deficiência do Complexo de Piruvato Desidrogenase/tratamento farmacológico , Tiamina/uso terapêutico , Encéfalo/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Doença da Deficiência do Complexo de Piruvato Desidrogenase/diagnóstico , Adulto Jovem
6.
JIMD Rep ; 12: 1-4, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23818179

RESUMO

INTRODUCTION: Propionic acidemia is a metabolic disease produced by a deficiency of the enzyme propionyl-CoA carboxylase. It can lead to coma, with severe neurologic encephalopathy or present later in life with vomiting, hypotonia, and seizures. An early diagnosis with adequate treatment helps to prevent the sequelae. Among the described complications is optic neuropathy, although not commonly reported, it is very disabling. OBJECTIVES: To describe two patients with propionic acidemia and optic neuropathy. PATIENTS AND METHODS: Patient 1: 16 years old, male, parents without consanguinity. He was diagnosed at 5 months of age because of hypotonia and seizures. Until the age of 9 years, he evolved satisfactorily; therefore, he stopped treatment. At 13 years, he presented bilateral optic neuropathy. Patient 2: 20 years, female, parents without consanguinity. She was diagnosed with PA at 11 months of age because of hypotonia and seizures. She evolved satisfactorily until the age of 9 years when she presented a metabolic decompensation followed by a bad metabolic control. At 18 years, she presented bilateral progressive optic neuropathy. RESULTS: Both patients have psychometric scores with borderline IQ 84-75 (WISC-R) beside optic neuropathy. They were evaluated by an ophthalmologist and also by neuroimaging (MRI of optic pathway). CONCLUSIONS: Pathophysiology of optic neuropathy is not completely understood. There is evidence that the damage is due to an accumulation of neurotoxic compounds secondary to the metabolic block increasing the oxidative stress. We suggest an annual ophthalmologic evaluation in the long-term follow-up of organic acidurias with visual loss, in order to detect this disabling sequela at an earlier stage.

7.
Horm Res Paediatr ; 79(4): 197-207, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23594793

RESUMO

BACKGROUND: Very low birth weight (VLBW) children have higher risk of neurologic disabilities and growth factors are essential for brain maturation. AIM: To assess whether there are differences in neurologic findings, psychometric parameters and microstructural brain morphology in 1-year-old VLBW infants versus term healthy controls and whether these differences are related to hormonal/growth changes. METHODS: Prospective anthropometry, prefeed venous blood sample [insulin, insulin-like growth factor-I (IGF-I), insulin-like growth factor-II (IGF-II), leptin, glucose], neurologic and imaging assessment, at age 1 year in 34 VLBW infants (12 SGA; 10 M) and 10 healthy term controls (5 M). RESULTS: IGF-I concentrations at 1 month of corrected age were 20% lower in SGA versus appropriate for gestational age VLBW (p < 0.02). Gray and white matter volume and fractional anisotropy in 15/27 regions were decreased (p < 0.001). Abnormal spectroscopy was observed in 4 zones in VLBW versus term controls (p < 0.001). Some of these changes were associated with different periods of first-year growth and IGF-I/IGF-II, leptin and HOMA-IR. CONCLUSIONS: VLBW infants show differences in brain volumes and microstructural brain morphology as compared to term controls, changes related to circulating growth factor and anthropometry changes in the first year. This apparent reorganization of the developing brain offers a unique opportunity to investigate the relationship between changes in cortical anatomy, cognitive and social impairments and periods of early growth.


Assuntos
Encéfalo/crescimento & desenvolvimento , Recém-Nascido de muito Baixo Peso/crescimento & desenvolvimento , Fator de Crescimento Insulin-Like I/metabolismo , Estatura , Peso Corporal , Feminino , Humanos , Lactente , Recém-Nascido Pequeno para a Idade Gestacional/sangue , Insulina/sangue , Fator de Crescimento Insulin-Like II/metabolismo , Leptina/sangue , Imageamento por Ressonância Magnética , Masculino , Estudos Prospectivos
8.
J Clin Endocrinol Metab ; 90(11): 6035-40, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16131574

RESUMO

CONTEXT: Isolated hypospadias may result from impaired testicular function or androgen end-organ defects or, alternatively, from hormone-independent abnormalities of morphogenetic events responsible for urethral seam. OBJECTIVE: The objective was to evaluate the relative prevalence of hormone-dependent etiologies in boys with isolated hypospadias. DESIGN, PATIENTS, AND MAIN OUTCOME MEASURES: We studied endocrine testicular capacity in 61 patients with isolated hypospadias and 28 with hypospadias associated with micropenis, cryptorchidism, or ambiguous genitalia. Serum anti-Müllerian hormone and inhibin B were used as Sertoli cell markers. A human chorionic gonadotropin test was performed to evaluate Leydig cell function. RESULTS: Testicular dysfunction was observed in 57.1% and androgen end-organ defects in 7.2% of patients with hypospadias associated with cryptorchidism, micropenis, or ambiguous genitalia. In the remaining 35.7%, the disorder was idiopathic. The presence of ambiguous genitalia predicted the existence of testicular or end-organ dysfunction with 81.8% specificity. Isolated hypospadias was associated in 14.8% of patients with testicular dysfunction and in 6.5% of cases with end-organ defects; in 78.7% of cases, the condition was idiopathic. The occurrence of isolated hypospadias ruled out the existence of testicular or end-organ disorders with 80.0% sensitivity. Altogether our data indicate that the risk for the existence of an underlying testicular or end-organ dysfunction is low in patients with isolated hypospadias (odds ratio, 0.13; 95% confidence interval, 0.05-0.36; P < 0.001). CONCLUSIONS: Boys with isolated hypospadias are more likely to have normal endocrine testicular and androgen end-organ functions, suggesting that transient disruption of morphogenetic events in early fetal life may be the predominant underlying cause.


Assuntos
Hipospadia/fisiopatologia , Células Intersticiais do Testículo/fisiologia , Células de Sertoli/fisiologia , Testículo/fisiopatologia , Hormônio Antimülleriano , Gonadotropina Coriônica/farmacologia , Di-Hidrotestosterona/sangue , Glicoproteínas/sangue , Humanos , Hipospadia/etiologia , Masculino , Risco , Hormônios Testiculares/sangue , Testosterona/sangue , Uretra/embriologia
9.
J Clin Endocrinol Metab ; 89(2): 957-64, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14764821

RESUMO

To determine whether some patients with idiopathic hypospadias have HSD3B2 mutations, we genotyped this locus in 90 patients with hypospadias (age, 6.0 +/- 0.4 yr) and 101 healthy fertile male controls. We measured basal plasma renin activity and performed an ACTH test for determination of 17-OH-pregnenolone, 17-OH-progesterone, cortisol, dehydroepiandrosterone sulfate, and androstenedione and an human chorionic gonadotropin test for determination of androstenedione, testosterone, and dihydrotestosterone. We did not observe a clear steroidogenic pattern suggestive of 3 beta-HSD deficiency in any patient. DNA was extracted from peripheral lymphocytes; and exons 1, 2, 3, and 4 were amplified by PCR and analyzed by denaturing gradient gel electrophoresis. An abnormal electrophoretic migration pattern of exon 4 was observed in five patients. Two patients had missense heterozygous mutations (S213T and S284R). In another three patients, we observed heterozygous nucleotide variants in exon 4 that did not produce a change in amino acids (A238, T259, T320). In vitro enzymatic activity was diminished by 40% and 32% in the S213T and S284R heterozygous mutations, respectively. One control exhibited a heterozygous mutation in exon 3 (V78I), which did not alter in vitro enzyme activity. In addition, we observed possible polymorphisms in intron 1 in four patients and one control. We conclude that subtle molecular abnormalities in the HSD3B2 gene may be observed in some patients with apparent idiopathic hypospadias but that this finding is uncommon.


Assuntos
3-Hidroxiesteroide Desidrogenases/genética , Hipospadia/genética , 3-Hidroxiesteroide Desidrogenases/metabolismo , Adolescente , Animais , Sequência de Bases/genética , Células COS , Estudos de Casos e Controles , Criança , Pré-Escolar , Chlorocebus aethiops , Humanos , Lactente , Recém-Nascido , Masculino , Dados de Sequência Molecular , Mutação/genética , Linhagem , Estudos Prospectivos
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