RESUMEN
Andersen-Tawil syndrome (ATS) is one of the periodic paralyses, a set of skeletal muscle disorders that cause transient weakness of the arms and legs lasting minutes to many hours. Distinguishing features of ATS include facial and limb dysmorphisms, cardiac arrhythmia, difficulties with executive function, and association with dominant mutations in the potassium channel, KCNJ2. In this review, we discuss the key features of ATS, diagnostic testing, pathophysiology and treatment of ATS, and compare them with other periodic paralyses.
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Síndrome de Andersen , Síndrome de Andersen/genética , Síndrome de Andersen/diagnóstico , Síndrome de Andersen/terapia , Síndrome de Andersen/fisiopatología , Humanos , Mutación/genética , Canales de Potasio de Rectificación Interna/genéticaRESUMEN
"Security by design" is the term for shifting cybersecurity considerations from a system's end users to its engineers. To reduce the end users' workload for addressing security during the systems operation phase, security decisions need to be made during engineering, and in a way that is traceable for third parties. However, engineers of cyber-physical systems (CPSs) or, more specifically, industrial control systems (ICSs) typically neither have the security expertise nor time for security engineering. The security-by-design decisions method presented in this work aims to enable them to identify, make, and substantiate security decisions autonomously. Core features of the method are a set of function-based diagrams as well as libraries of typical functions and their security parameters. The method, implemented as a software demonstrator, is validated in a case study with the specialist for safety-related automation solutions HIMA, and the results show that the method enables engineers to identify and make security decisions they may not have made (consciously) otherwise, and quickly and with little security expertise. The method is also well suited to make security-decision-making knowledge available to less experienced engineers. This means that with the security-by-design decisions method, more people can contribute to a CPS's security by design in less time.
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Seguridad Computacional , Programas Informáticos , Humanos , IngenieríaRESUMEN
BACKGROUND: INAD is an autosomal recessive neurogenetic disorder caused by biallelic pathogenic variants in PLA2G6. The downstream enzyme, iPLA2, plays a critical role in cell membrane homeostasis by helping to regulate levels of phospholipids. The clinical presentation occurs between 6 months and 3 years with global developmental regression, hypotonia, and progressive spastic tetraparesis. Progression is often rapid, resulting in severe spasticity, visual impairment, and cognitive decline, with many children not surviving past the first decade of life. To date, no accepted tool for assessing the severity of INAD exists; other commonly used scales (e.g. CHOP-INTEND, Modified Ashworth, Hammersmith Functional Motor Scale) do not accurately gauge the current severity of INAD, nor are they sensitive/specific enough to monitor disease progression. Finally, these other scales are not appropriate, because they do not address the combination of CNS, peripheral nerve, and visual pathology that occurs in children with INAD. METHODS: We have developed and validated a structured neurological examination for INAD (scored out of 80). The examination includes six main categories of pediatric developmental evaluation: 1) gross motor-and-truncal-stability skills, 2) fine motor skills, 3) bulbar function, 4) ocular function, 5) temporo-frontal function, and, 6) Functional evaluation of the autonomic nervous system. A cohort of patients diagnosed with INAD were followed prospectively to validate the score against disease severity and disease progression. RESULTS: We show significant correlation between the total neurological assessment score and months since symptom onset with a statistically significant (p = 6.7 × 10- 07) correlation between assessment score and disease onset. As hypothesized, the coefficient of months-since-symptom-onset is strongly negative, indicating a negative correlation between total score and months since symptom onset. CONCLUSION: We have developed and validated a novel neurological assessment score in INAD that demonstrates strong correlation with disease severity and disease progression.
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Distrofias Neuroaxonales , Niño , Humanos , Distrofias Neuroaxonales/diagnóstico , Distrofias Neuroaxonales/genética , Nervios PeriféricosRESUMEN
OBJECTIVE: The objective of this study was to identify the genetic cause for progressive peripheral nerve disease in a Venezuelan family. Despite the growing list of genes associated with Charcot-Marie-Tooth disease, many patients with axonal forms lack a genetic diagnosis. METHODS: A pedigree was constructed, based on family clinical data. Next-generation sequencing of mitochondrial DNA (mtDNA) was performed for 6 affected family members. Muscle biopsies from 4 family members were used for analysis of muscle histology and ultrastructure, mtDNA sequencing, and RNA quantification. Ultrastructural studies were performed on sensory nerve biopsies from 2 affected family members. RESULTS: Electrodiagnostic testing showed a motor and sensory axonal polyneuropathy. Pedigree analysis revealed inheritance only through the maternal line, consistent with mitochondrial transmission. Sequencing of mtDNA identified a mutation in the mitochondrial tRNAVal (mt-tRNAVal ) gene, m.1661A>G, present at nearly 100% heteroplasmy, which disrupts a Watson-Crick base pair in the T-stem-loop. Muscle biopsies showed chronic denervation/reinnervation changes, whereas biochemical analysis of electron transport chain (ETC) enzyme activities showed reduction in multiple ETC complexes. Northern blots from skeletal muscle total RNA showed severe reduction in abundance of mt-tRNAVal , and mildly increased mt-tRNAPhe , in subjects compared with unrelated age- and sex-matched controls. Nerve biopsies from 2 affected family members demonstrated ultrastructural mitochondrial abnormalities (hyperplasia, hypertrophy, and crystalline arrays) consistent with a mitochondrial neuropathy. CONCLUSION: We identify a previously unreported cause of Charcot-Marie-Tooth (CMT) disease, a mutation in the mt-tRNAVal , in a Venezuelan family. This work expands the list of CMT-associated genes from protein-coding genes to a mitochondrial tRNA gene. ANN NEUROL 2020;88:830-842.
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Enfermedad de Charcot-Marie-Tooth/genética , ARN Mitocondrial/genética , ARN de Transferencia/genética , Adolescente , Adulto , Anciano de 80 o más Años , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mutación , Linaje , Venezuela , Adulto JovenRESUMEN
BACKGROUND: Dyskinesia is a troublesome complication of long-term dopaminergic medications in Parkinson's disease (PD) patients. Many factors are reported to be associated with dyskinesia in PD. OBJECTIVE: To investigate the association between sleep quality and dyskinesia in patients with PD. METHODS: Four hundred twenty-five patients with PD were enrolled in this study. Demographic information was collected. Unified Parkinson's Disease Rating Scale (UPDRS) and Hoehn and Yahr (H-Y) stage scale were also performed. Epworth Sleepiness Scale (ESS) and Pittsburgh Sleep Quality Index (PSQI) were applied to evaluate daytime sleepiness and overall nighttime sleep quality, respectively, in PD patients. RESULTS: Patients with dyskinesia tended to have a longer duration of disease, higher daily levodopa-equivalent dose (LED), H-Y stage, UPDRS II and PSQI score, and a higher percentage of levodopa treatment than those without dyskinesia. After adjusting for age, sex, age at onset of PD, disease duration, UPDRS I, UPDRS II, UPDRS III, cigarette smoking, use of different antiparkinsonian drugs, phenotype, daily LED, and restless leg syndrome (RLS), PSQI score was still associated with dyskinesia, with corresponding ORs 1.111 (95% CI, 1.004-1.229) as a continuous variable, and 2.469 (95% CI, 1.051-5.800) as a categorical variable, respectively. Further analysis of PSQI components showed that subjective sleep quality and sleep latency were associated with dyskinesia in PD patients. CONCLUSIONS: Our data showed that poor nighttime sleep is positively associated with dyskinesia in PD patients. Attention to the management of nighttime sleep quality may be beneficial to dyskinesia in patients with PD.
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Discinesia Inducida por Medicamentos/complicaciones , Trastornos del Inicio y del Mantenimiento del Sueño/complicaciones , Trastornos del Sueño-Vigilia/complicaciones , Anciano , Antiparkinsonianos/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/tratamiento farmacológico , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Estadísticas no Paramétricas , Encuestas y CuestionariosRESUMEN
Although ribosomes are ubiquitous and essential for life, recent data indicate that monogenic causes of ribosomal dysfunction can confer a remarkable degree of specificity in terms of human disease phenotype. Box C/D small nucleolar RNAs (snoRNAs) are evolutionarily conserved non-protein-coding RNAs involved in ribosome biogenesis. Here we show that biallelic mutations in the gene SNORD118, encoding the box C/D snoRNA U8, cause the cerebral microangiopathy leukoencephalopathy with calcifications and cysts (LCC), presenting at any age from early childhood to late adulthood. These mutations affect U8 expression, processing and protein binding and thus implicate U8 as essential in cerebral vascular homeostasis.
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Enfermedades de los Pequeños Vasos Cerebrales/genética , Leucoencefalopatías/genética , Mutación , ARN Nucleolar Pequeño/genética , Adolescente , Adulto , Calcinosis/genética , Calcinosis/patología , Línea Celular , Enfermedades de los Pequeños Vasos Cerebrales/patología , Niño , Preescolar , Cromosomas Humanos Par 17 , Estudios de Cohortes , Quistes/genética , Quistes/patología , Exoma , Femenino , Ligamiento Genético , Genoma Humano , Humanos , Lactante , Leucoencefalopatías/patología , Masculino , Persona de Mediana Edad , Análisis de Secuencia de ADN , Adulto JovenRESUMEN
Congenital disorders of glycosylation (CDG) arise from pathogenic mutations in over 100 genes leading to impaired protein or lipid glycosylation. ALG1 encodes a ß1,4 mannosyltransferase that catalyzes the addition of the first of nine mannose moieties to form a dolichol-lipid linked oligosaccharide intermediate required for proper N-linked glycosylation. ALG1 mutations cause a rare autosomal recessive disorder termed ALG1-CDG. To date 13 mutations in 18 patients from 14 families have been described with varying degrees of clinical severity. We identified and characterized 39 previously unreported cases of ALG1-CDG from 32 families and add 26 new mutations. Pathogenicity of each mutation was confirmed based on its inability to rescue impaired growth or hypoglycosylation of a standard biomarker in an alg1-deficient yeast strain. Using this approach we could not establish a rank order comparison of biomarker glycosylation and patient phenotype, but we identified mutations with a lethal outcome in the first two years of life. The recently identified protein-linked xeno-tetrasaccharide biomarker, NeuAc-Gal-GlcNAc2 , was seen in all 27 patients tested. Our study triples the number of known patients and expands the molecular and clinical correlates of this disorder.
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Trastornos Congénitos de Glicosilación/genética , Manosiltransferasas/genética , Mutación , Polisacáridos/metabolismo , Biomarcadores/metabolismo , Trastornos Congénitos de Glicosilación/metabolismo , Femenino , Genes Letales , Glicosilación , Humanos , Masculino , Análisis de Secuencia de ADN , Análisis de SupervivenciaRESUMEN
OBJECTIVE: We determined the effect of perinatally acquired HIV on neurocognition in Myanmar children treated with antiretroviral therapy by comparison to demographically matched seronegative children. BACKGROUND: Myanmar has one of the highest HIV-1 prevalence rates in Southeast Asia. Studies from other resource-poor countries have shown that HIV-infected children differ in socioeconomic, nutritional and caregiver status compared to normal controls. Some vertically infected orphans in Myanmar reside separately from HIV-uninfected children in separate orphanages, thus the demographic variables of interest are naturally controlled. This study provides a unique evaluation of the neurocognitive effects of HIV in children, with control over key demographic variables. We hypothesized that HIV-infected orphans would perform significantly worse on cognitive indices compared with HIV-negative orphans. DESIGN/METHODS: A battery of cognitive tests sensitive to HIV-associated impairments in children was administered to 28 perinatally acquired HIV-positive children and 31 HIV-negative children from two orphanages in Myanmar; 21 children from each cohort underwent testing at baseline and again after 12 months. RESULTS: Baseline comparison of the two groups indicated that the HIV-infected children performed poorly across all tests, with significant group differences in executive function, visuospatial reasoning, fine motor dexterity, and visual motor integration. On subsequent testing, both cohorts of children showed improvements across multiple domains, with no significant effect of age at treatment initiation. CONCLUSIONS: Our results demonstrate a strong effect of HIV infection on specific neurocognitive deficits in vertically infected children. Understanding viral and host determinants and timing and choice of antiretroviral therapy on cognition will be critical to preventing cognitive impairment of children with HIV.