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1.
Am J Med Genet A ; 191(12): 2890-2897, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37654102

RESUMEN

Mitochondrial disorders can present with a wide range of clinical and biochemical phenotypes. Mitochondrial DNA variants may be influenced by factors such as degree of heteroplasmy and tissue distribution. We present a four-generation family in which 10 individuals carry a pathogenic mitochondrial variant (m.5537_5538insT, MT-TW gene) with differing levels of heteroplasmy and clinical features. This genetic variant has been documented in two prior reports, both in individuals with Leigh syndrome. In the current family, three individuals have severe mitochondrial symptoms including Leigh syndrome (patient 1, 100% in blood), MELAS (patient 2, 97% heteroplasmy in muscle), and MELAS-like syndrome (patient 3, 50% heteroplasmy in blood and 100% in urine). Two individuals have mild mitochondrial symptoms (patient 4, 50% in blood and 67% in urine and patient 5, 50% heteroplasmy in blood and 30% in urine). We observe that this variant is associated with multiple mitochondrial presentations and phenotypes, including MELAS syndrome for which this variant has not previously been reported. We also demonstrate that the level of heteroplasmy of the mitochondrial DNA variant correlates with the severity of clinical presentation; however, not with the specific mitochondrial syndrome.


Asunto(s)
Enfermedad de Leigh , Síndrome MELAS , Enfermedades Mitocondriales , Humanos , Síndrome MELAS/diagnóstico , Síndrome MELAS/genética , Síndrome MELAS/complicaciones , Enfermedad de Leigh/diagnóstico , Enfermedad de Leigh/genética , Enfermedad de Leigh/complicaciones , Mitocondrias/genética , ADN Mitocondrial/genética , Enfermedades Mitocondriales/diagnóstico , Enfermedades Mitocondriales/genética , Enfermedades Mitocondriales/complicaciones
2.
Am J Med Genet A ; 185(11): 3502-3506, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34405953

RESUMEN

Biallelic pathogenic variants in RNU4ATAC have been linked to microcephalic osteodysplastic primordial dwarfism type 1 (MOPD1). Although children with MOPD1 have been reported to show profound, life-limiting clinical decompensation at the time of a febrile illness, these episodes including magnetic resonance imaging (MRI) findings have not been well characterized. We present acute MRI brain findings for a 10-year-old girl with homozygous variants in RNU4ATAC (NR_023343.1) n.55G>A, who presented with two episodes of clinical decompensation associated with a febrile illness in early childhood. The pathogenic variants were identified by whole genome sequencing as RNU4ATAC is not captured in most exome products. Her MRI of the brain revealed symmetric, diffusion restriction of the deep gray nuclei that initially pointed to a mitochondrial disease or acute necrotizing encephalopathy. Her phenotype included microcephaly and profound cognitive impairment that can be seen with MOPD1. However, she did not demonstrate clinical or radiographic evidence of a spondyloepimetaphyseal dysplasia or "primordial dwarfism" that is characteristic of this disease. As such, the predominant neurological presentation of this child represents an atypical variant of RNU4ATAC-associated disease and should be a diagnostic consideration for geneticists and neurologists caring for children, particularly in the event of an acute clinical decline.


Asunto(s)
Enanismo/genética , Encefalitis/genética , Retardo del Crecimiento Fetal/genética , Microcefalia/genética , Osteocondrodisplasias/genética , ARN Nuclear Pequeño/genética , Encéfalo/anomalías , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Niño , Preescolar , Enanismo/diagnóstico por imagen , Enanismo/patología , Encefalitis/diagnóstico por imagen , Encefalitis/patología , Exoma/genética , Femenino , Retardo del Crecimiento Fetal/diagnóstico por imagen , Retardo del Crecimiento Fetal/patología , Predisposición Genética a la Enfermedad , Humanos , Lactante , Recién Nacido , Imagen por Resonancia Magnética , Masculino , Microcefalia/diagnóstico por imagen , Microcefalia/patología , Mutación/genética , Osteocondrodisplasias/diagnóstico por imagen , Osteocondrodisplasias/patología , Fenotipo , Secuenciación del Exoma , Secuenciación Completa del Genoma
3.
Can Assoc Radiol J ; 71(4): 505-513, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32054306

RESUMEN

Infantile hemangiomas are the most frequent vascular soft tissue lumps in the pediatric population. The clinical presentation and evolution of these lesions is characteristic, while the sonographic appearance is classic but not specific. This pictorial essay illustrates the different vascular soft tissue lumps on ultrasound that may mimic infantile hemangiomas. Awareness of these mimics is crucial to avoid misdiagnosis. Clinical and sonographic discriminators for each lesion are presented.


Asunto(s)
Hemangioma/diagnóstico por imagen , Neoplasias de los Tejidos Blandos/irrigación sanguínea , Neoplasias de los Tejidos Blandos/diagnóstico por imagen , Ultrasonografía/métodos , Niño , Diagnóstico Diferencial , Humanos
4.
Can Assoc Radiol J ; 71(2): 217-225, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32062992

RESUMEN

PURPOSE: The aim of our study was to compare whole-body diffusion-weighted MRI (WB-DWI-MRI) to fluoro-2-deoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) in the assessment of initial staging and treatment response in pediatric patients with Hodgkin lymphoma. MATERIALS AND METHODS: This prospective study comprised 11 children with Hodgkin lymphoma. Whole-body DWI-MRI and FDG-PET/CT were obtained at baseline and after 2 cycles of chemotherapy. Two radiologists measured the apparent diffusion coefficient (ADC) values of the sites of involvement agreed upon in consensus and 1 nuclear medicine physician assessed the PET/CT. Reliability of radiologists' ratings was assessed by intraclass correlation coefficients (ICC2,1). The sensitivity and positive predictive value (PPV) of DW-MRI relative to PET/CT were calculated for nodal and extranodal sites. The patients were staged according to both modalities. Association of treatment responses was assessed through the Pearson correlation between the ADC ratios and the change standardized uptake value (SUV) between baseline and follow-up. RESULTS: There was good agreement between the raters for nodal and extranodal ADC measurements. The sensitivity and PPV of DW-MRI relative to PET/CT of nodal disease was 0.651 and 1.0, respectively, at baseline, and 0.697 and 0.885 at follow-up. The sensitivity and PPV of extranodal disease were 0.545 and 0.6 at baseline, and 0.167 and 0.333 at follow-up. Diffusion-weighted MRI determined correct tumor stage in 8 of 11 examinations. There was poor correlation between the ADC ratios and the absolute change in SUV between baseline and follow-up (0.348). CONCLUSION: Our experience showed that WB-DWI-MRI is inferior to PET/CT for initial staging and assessment of treatment response of Hodgkin lymphoma in pediatric patients.


Asunto(s)
Imagen de Difusión por Resonancia Magnética , Enfermedad de Hodgkin/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones , Imagen de Cuerpo Entero/métodos , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Niño , Femenino , Fluorodesoxiglucosa F18 , Enfermedad de Hodgkin/tratamiento farmacológico , Enfermedad de Hodgkin/patología , Humanos , Ganglios Linfáticos/diagnóstico por imagen , Masculino , Estadificación de Neoplasias , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Estudios Prospectivos , Radiofármacos , Reproducibilidad de los Resultados
5.
Clin Genet ; 95(5): 601-606, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30790272

RESUMEN

The GTPBP2 gene encodes a guanosine triphosphate (GTP)-binding protein of unknown function. Biallelic loss-of-function variants in the GTPBP2 gene have been previously reported in association with a neuro-ectodermal clinical presentation in six individuals from four unrelated families. Here, we provide detailed descriptions of three additional individuals from two unrelated families in the context of the previous literature. Both families carry nonsense variants in GTPBP2: homozygous p.(Arg470*) and compound heterozygous p.(Arg432*)/p.(Arg131*). Key features of this clinically recognizable condition include prenatal onset microcephaly, tone abnormalities, and movement disorders, epilepsy, dysmorphic features, retinal dysfunction, ectodermal dysplasia, and brain iron accumulation. Our findings suggest that some aspects of the clinical presentation appear to be age-related; brain iron accumulation may appear only after childhood, and the ectodermal findings and peripheral neuropathy are most prominent in older individuals. In addition, we present prenatal and neonatal findings as well as the first Caucasian and black African families with GTPBP2 biallelic variants. The individuals described herein provide valuable additional phenotypic information about this rare, novel, and progressive neuroectodermal condition.


Asunto(s)
Ectodermo/patología , Proteínas de Unión al GTP/genética , Familia , Humanos , Síndrome , Secuenciación del Exoma
7.
Ecotoxicol Environ Saf ; 170: 293-299, 2019 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-30530181

RESUMEN

Di(2-ethylhexyl) phthalate (DEHP) is a widely used plasticizer, which is considered an endocrine disrupting pollutant. Growth kinetics and esterases activity by biochemical tests and polyacrylamide gel electrophoresis were characterized for Fusarium culmorum grown in DEHP-supplemented (1000 mg/L) medium as the only carbon source and in control medium with glucose. Intermediate compounds of biodegraded DEHP were identified by GC-MS. F. culmorum degraded 92% of DEHP within 36 h. DEHP was degraded to butanol, hexanal, catechol and acetic acid. It is suggested that the first two compounds would transform into butanediol and the last two would enter into the Krebs cycle and would be mineralized to CO2 and H2O. DEHP induced eight esterase isoforms, which were different to those constitutive isoforms produced in the control medium. It is suggested that five enzymes (25.7, 29.5, 31.8, 97.6 and 144.5 kDa) detected during the first 36 h be involved in the primary biodegradation of DEHP. The rest of the enzymes (45.9, 66.6 and 202.9 kDa) might be involved in the final steps for DEHP metabolism. F. culmorum has a promising practical application in the treatment of DEHP-contaminated environments because it can secrete specific esterase to breakdown high concentrations of DEHP in a short period of time. This research represents the first approach for the study of esterase involved in the DEHP degradation by fungi using this phthalate as the sole source of carbon and energy.


Asunto(s)
Dietilhexil Ftalato/análisis , Disruptores Endocrinos/análisis , Contaminantes Ambientales/análisis , Fusarium/crecimiento & desarrollo , Plastificantes/análisis , Biodegradación Ambiental , Esterasas/metabolismo , Fusarium/enzimología , Cinética
8.
Pediatr Radiol ; 48(13): 1833-1843, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29980859

RESUMEN

Pediatric brain tumors differ from those in adults by location, phenotype and genotype. In addition, they show dissimilar imaging characteristics before and after treatment. While adult brain tumor treatment effects are primarily assessed on MRI by measuring the contrast-enhancing components in addition to abnormalities on T2-weighted and fluid-attenuated inversion recovery images, these methods cannot be simply extrapolated to pediatric central nervous system tumors. A number of researchers have attempted to solve the problem of tumor assessment during treatment in pediatric neuro-oncology; specifically, the Response Assessment in Pediatric Neuro-Oncology (RAPNO) working group was recently established to deal with the distinct challenges in evaluating treatment-related changes on imaging, but no established criteria are available. In this article we review the current methods to evaluate brain tumor therapy and the numerous challenges that remain. In part 1, we examine the role of T2-weighted imaging and fluid-attenuated inversion recovery sequences, contrast enhancement, volumetrics and diffusion imaging techniques. We pay particular attention to several specific pediatric brain tumors, such as optic pathway glioma, diffuse midline glioma and medulloblastoma. Finally, we review the best means to assess leptomeningeal seeding.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/terapia , Imagen por Resonancia Magnética/métodos , Neuroimagen/métodos , Neoplasias Encefálicas/patología , Niño , Medios de Contraste , Diagnóstico Diferencial , Humanos , Fenotipo , Carga Tumoral
9.
Ecotoxicol Environ Saf ; 147: 494-499, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28915396

RESUMEN

Di(2-ethyl hexyl) phthalate (DEHP) is a plasticizer that interfere with endocrine systems in mammals. Growth parameters for Pleurotus ostreatus grown on media containing glucose and different concentrations of DEHP (0, 500 and 1000mg/L) were evaluated. The highest biomass production was observed in medium supplemented with 1000mg of DEHP/L. Half-life of DEHP biodegradation, biodegradation constant of DEHP, and percentage of removal efficiency (%E) were also determined. P. ostreatus degraded 100% of DEHP after 504h. %E was 99.3% and 98.4% for 500 and 1000mg of DEHP/L, respectively. Intermediate compounds of biodegraded DEHP were identified by GC-MS and a DEHP biodegradation pathway was proposed using quantum chemical investigation. DEHP might be metabolized through three pathways; a de-esterification pathway, an oxidation pathway and an oxidation-hydrolysis pathway, forming phthalic acid, acetic acid and butanediol, respectively. P. ostreatus degrades and uses (as carbon and energy source) high concentrations of DEHP.


Asunto(s)
Dietilhexil Ftalato/análisis , Disruptores Endocrinos/análisis , Plastificantes/análisis , Pleurotus/metabolismo , Animales , Biodegradación Ambiental , Biomasa , Biotransformación , Dietilhexil Ftalato/metabolismo , Disruptores Endocrinos/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Semivida , Plastificantes/metabolismo , Pleurotus/crecimiento & desarrollo
10.
Am J Med Genet B Neuropsychiatr Genet ; 177(1): 101-109, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29152901

RESUMEN

White matter lesions have been described in patients with PTEN hamartoma tumor syndrome (PHTS). How these lesions correlate with the neurocognitive features associated with PTEN mutations, such as autism spectrum disorder (ASD) or developmental delay, has not been well established. We report nine patients with PTEN mutations and white matter changes on brain magnetic resonance imaging (MRI), eight of whom were referred for reasons other than developmental delay or ASD. Their clinical presentations ranged from asymptomatic macrocephaly with normal development/intellect, to obsessive compulsive disorder, and debilitating neurological disease. To our knowledge, this report constitutes the first detailed description of PTEN-related white matter changes in adult patients and in children with normal development and intelligence. We present a detailed assessment of the neuropsychological phenotype of our patients and discuss the relationship between the wide array of neuropsychiatric features and observed white matter findings in the context of these individuals.


Asunto(s)
Síndrome de Hamartoma Múltiple/fisiopatología , Leucoencefalopatías/metabolismo , Fosfohidrolasa PTEN/metabolismo , Adolescente , Adulto , Trastorno del Espectro Autista/genética , Niño , Preescolar , Discapacidades del Desarrollo , Femenino , Síndrome de Hamartoma Múltiple/genética , Humanos , Inteligencia , Leucoencefalopatías/genética , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Fenotipo , Sustancia Blanca/patología
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