Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 96
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Brain ; 145(11): 3832-3842, 2022 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-36071595

RESUMEN

Prenatal exposure to the anti-seizure medication sodium valproate (VPA) is associated with an increased risk of adverse postnatal neurodevelopmental outcomes, including lowered intellectual ability, autism spectrum disorder and attention-deficit hyperactivity disorder. In this study, we aimed to clarify the molecular mechanisms underpinning the neurodevelopmental consequences of gestational VPA exposure using integrative genomics. We assessed the effect of gestational VPA on foetal brain gene expression using a validated rat model of valproate teratogenicity that mimics the human scenario of chronic oral valproate treatment during pregnancy at doses that are therapeutically relevant to the treatment of epilepsy. Two different rat strains were studied-inbred Genetic Absence Epilepsy Rats from Strasbourg, a model of genetic generalized epilepsy, and inbred non-epileptic control rats. Female rats were fed standard chow or VPA mixed in standard chow for 2 weeks prior to conception and then mated with same-strain males. In the VPA-exposed rats maternal oral treatment was continued throughout pregnancy. Foetuses were extracted via C-section on gestational Day 21 (1 day prior to birth) and foetal brains were snap-frozen and genome-wide gene expression data generated. We found that gestational VPA exposure via chronic maternal oral dosing was associated with substantial drug-induced differential gene expression in the pup brains, including dysregulated splicing, and observed that this occurred in the absence of evidence for significant neuronal gain or loss. The functional consequences of VPA-induced gene expression were explored using pathway analysis and integration with genetic risk data for psychiatric disease and behavioural traits. The set of genes downregulated by VPA in the pup brains were significantly enriched for pathways related to neurodevelopment and synaptic function and significantly enriched for heritability to human intelligence, schizophrenia and bipolar disorder. Our results provide a mechanistic link between chronic foetal VPA exposure and neurodevelopmental disability mediated by VPA-induced transcriptional dysregulation.


Asunto(s)
Trastorno del Espectro Autista , Epilepsia Tipo Ausencia , Efectos Tardíos de la Exposición Prenatal , Embarazo , Masculino , Femenino , Ratas , Humanos , Animales , Ácido Valproico/toxicidad , Ácido Valproico/uso terapéutico , Anticonvulsivantes/toxicidad , Anticonvulsivantes/uso terapéutico , Trastorno del Espectro Autista/tratamiento farmacológico , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Genómica
2.
Health Care Manag Sci ; 26(3): 477-500, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37199873

RESUMEN

During the COVID-19 pandemic, there has been considerable research on how regional and country-level forecasting can be used to anticipate required hospital resources. We add to and build on this work by focusing on ward-level forecasting and planning tools for hospital staff during the pandemic. We present an assessment, validation, and deployment of a working prototype forecasting tool used within a modified Traffic Control Bundling (TCB) protocol for resource planning during the pandemic. We compare statistical and machine learning forecasting methods and their accuracy at one of the largest hospitals (Vancouver General Hospital) in Canada against a medium-sized hospital (St. Paul's Hospital) in Vancouver, Canada through the first three waves of the COVID-19 pandemic in the province of British Columbia. Our results confirm that traditional statistical and machine learning (ML) forecasting methods can provide valuable ward-level forecasting to aid in decision-making for pandemic resource planning. Using point forecasts with upper 95% prediction intervals, such forecasting methods would have provided better accuracy in anticipating required beds on COVID-19 hospital units than ward-level capacity decisions made by hospital staff. We have integrated our methodology into a publicly available online tool that operationalizes ward-level forecasting to aid with capacity planning decisions. Importantly, hospital staff can use this tool to translate forecasts into better patient care, less burnout, and improved planning for all hospital resources during pandemics.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Pandemias , Hospitales , Predicción
3.
Acta Neuropathol ; 142(3): 449-474, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34309761

RESUMEN

Parkinson's disease (PD), Parkinson's disease with dementia (PDD) and dementia with Lewy bodies (DLB) are three clinically, genetically and neuropathologically overlapping neurodegenerative diseases collectively known as the Lewy body diseases (LBDs). A variety of molecular mechanisms have been implicated in PD pathogenesis, but the mechanisms underlying PDD and DLB remain largely unknown, a knowledge gap that presents an impediment to the discovery of disease-modifying therapies. Transcriptomic profiling can contribute to addressing this gap, but remains limited in the LBDs. Here, we applied paired bulk-tissue and single-nucleus RNA-sequencing to anterior cingulate cortex samples derived from 28 individuals, including healthy controls, PD, PDD and DLB cases (n = 7 per group), to transcriptomically profile the LBDs. Using this approach, we (i) found transcriptional alterations in multiple cell types across the LBDs; (ii) discovered evidence for widespread dysregulation of RNA splicing, particularly in PDD and DLB; (iii) identified potential splicing factors, with links to other dementia-related neurodegenerative diseases, coordinating this dysregulation; and (iv) identified transcriptomic commonalities and distinctions between the LBDs that inform understanding of the relationships between these three clinical disorders. Together, these findings have important implications for the design of RNA-targeted therapies for these diseases and highlight a potential molecular "window" of therapeutic opportunity between the initial onset of PD and subsequent development of Lewy body dementia.


Asunto(s)
Perfilación de la Expresión Génica/métodos , Enfermedad por Cuerpos de Lewy/genética , Enfermedad por Cuerpos de Lewy/patología , Patología Molecular/métodos , Anciano , Empalme Alternativo , Enfermedad de Alzheimer , Bancos de Muestras Biológicas , Núcleo Celular/genética , Núcleo Celular/ultraestructura , Giro del Cíngulo/patología , Humanos , Cuerpos de Lewy/patología , Microglía/patología , Microglía/ultraestructura , Miocitos del Músculo Liso/patología , Miocitos del Músculo Liso/ultraestructura , Enfermedad de Parkinson , ARN/genética , Transcriptoma
4.
Neurobiol Dis ; 134: 104664, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31678583

RESUMEN

Epilepsy is a complex network phenomenon that, as yet, cannot be prevented or cured. We recently proposed network-based approaches to prevent epileptogenesis. For proof of concept we combined two drugs (levetiracetam and topiramate) for which in silico analysis of drug-protein interaction networks indicated a synergistic effect on a large functional network of epilepsy-relevant proteins. Using the intrahippocampal kainate mouse model of temporal lobe epilepsy, the drug combination was administered during the latent period before onset of spontaneous recurrent seizures (SRS). When SRS were periodically recorded by video-EEG monitoring after termination of treatment, a significant decrease in incidence and frequency of SRS was determined, indicating antiepileptogenic efficacy. Such efficacy was not observed following single drug treatment. Furthermore, a combination of levetiracetam and phenobarbital, for which in silico analysis of drug-protein interaction networks did not indicate any significant drug-drug interaction, was not effective to modify development of epilepsy. Surprisingly, the promising antiepileptogenic effect of the levetiracetam/topiramate combination was obtained in the absence of any significant neuroprotective or anti-inflammatory effects as indicated by multimodal brain imaging and histopathology. High throughput RNA-sequencing (RNA-seq) of the ipsilateral hippocampus of mice treated with the levetiracetam/topiramate combination showed that several genes that have been linked previously to epileptogenesis, were significantly differentially expressed, providing interesting entry points for future mechanistic studies. Overall, we have discovered a novel combination treatment with promise for prevention of epilepsy.


Asunto(s)
Anticonvulsivantes/farmacología , Encéfalo/efectos de los fármacos , Quimioterapia Combinada/métodos , Epilepsia del Lóbulo Temporal , Mapeo de Interacción de Proteínas/métodos , Animales , Levetiracetam/farmacología , Masculino , Ratones , Prueba de Estudio Conceptual , Topiramato/farmacología , Transcriptoma/efectos de los fármacos
5.
Genome Res ; 27(3): 440-450, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28250018

RESUMEN

The recoding of genetic information through RNA editing contributes to proteomic diversity, but the extent and significance of RNA editing in disease is poorly understood. In particular, few studies have investigated the relationship between RNA editing and disease at a genome-wide level. Here, we developed a framework for the genome-wide detection of RNA sites that are differentially edited in disease. Using RNA-sequencing data from 100 hippocampi from mice with epilepsy (pilocarpine-temporal lobe epilepsy model) and 100 healthy control hippocampi, we identified 256 RNA sites (overlapping with 87 genes) that were significantly differentially edited between epileptic cases and controls. The degree of differential RNA editing in epileptic mice correlated with frequency of seizures, and the set of genes differentially RNA-edited between case and control mice were enriched for functional terms highly relevant to epilepsy, including "neuron projection" and "seizures." Genes with differential RNA editing were preferentially enriched for genes with a genetic association to epilepsy. Indeed, we found that they are significantly enriched for genes that harbor nonsynonymous de novo mutations in patients with epileptic encephalopathy and for common susceptibility variants associated with generalized epilepsy. These analyses reveal a functional convergence between genes that are differentially RNA-edited in acquired symptomatic epilepsy and those that contribute risk for genetic epilepsy. Taken together, our results suggest a potential role for RNA editing in the epileptic hippocampus in the occurrence and severity of epileptic seizures.


Asunto(s)
Epilepsia/genética , Edición de ARN , Animales , Estudio de Asociación del Genoma Completo , Hipocampo/metabolismo , Masculino , Ratones , Transcriptoma
6.
Epilepsia ; 61(4): 657-666, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32141622

RESUMEN

OBJECTIVE: Drug resistance is a major concern in the treatment of individuals with epilepsy. No genetic markers for resistance to individual antiseizure medication (ASM) have yet been identified. We aimed to identify the role of rare genetic variants in drug resistance for three common ASMs: levetiracetam (LEV), lamotrigine (LTG), and valproic acid (VPA). METHODS: A cohort of 1622 individuals of European descent with epilepsy was deeply phenotyped and underwent whole exome sequencing (WES), comprising 575 taking LEV, 826 LTG, and 782 VPA. We performed gene- and gene set-based collapsing analyses comparing responders and nonresponders to the three drugs to determine the burden of different categories of rare genetic variants. RESULTS: We observed a marginally significant enrichment of rare missense, truncating, and splice region variants in individuals who were resistant to VPA compared to VPA responders for genes involved in VPA pharmacokinetics. We also found a borderline significant enrichment of truncating and splice region variants in the synaptic vesicle glycoprotein (SV2) gene family in nonresponders compared to responders to LEV. We did not see any significant enrichment using a gene-based approach. SIGNIFICANCE: In our pharmacogenetic study, we identified a slightly increased burden of damaging variants in gene groups related to drug kinetics or targeting in individuals presenting with drug resistance to VPA or LEV. Such variants could thus determine a genetic contribution to drug resistance.


Asunto(s)
Anticonvulsivantes/uso terapéutico , Resistencia a Medicamentos/genética , Epilepsia/tratamiento farmacológico , Epilepsia/genética , Variantes Farmacogenómicas/genética , Estudios de Casos y Controles , Femenino , Genotipo , Humanos , Lamotrigina/uso terapéutico , Levetiracetam/uso terapéutico , Masculino , Ácido Valproico/uso terapéutico
7.
Nature ; 501(7466): 217-21, 2013 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-23934111

RESUMEN

Epileptic encephalopathies are a devastating group of severe childhood epilepsy disorders for which the cause is often unknown. Here we report a screen for de novo mutations in patients with two classical epileptic encephalopathies: infantile spasms (n = 149) and Lennox-Gastaut syndrome (n = 115). We sequenced the exomes of 264 probands, and their parents, and confirmed 329 de novo mutations. A likelihood analysis showed a significant excess of de novo mutations in the ∼4,000 genes that are the most intolerant to functional genetic variation in the human population (P = 2.9 × 10(-3)). Among these are GABRB3, with de novo mutations in four patients, and ALG13, with the same de novo mutation in two patients; both genes show clear statistical evidence of association with epileptic encephalopathy. Given the relevant site-specific mutation rates, the probabilities of these outcomes occurring by chance are P = 4.1 × 10(-10) and P = 7.8 × 10(-12), respectively. Other genes with de novo mutations in this cohort include CACNA1A, CHD2, FLNA, GABRA1, GRIN1, GRIN2B, HNRNPU, IQSEC2, MTOR and NEDD4L. Finally, we show that the de novo mutations observed are enriched in specific gene sets including genes regulated by the fragile X protein (P < 10(-8)), as has been reported previously for autism spectrum disorders.


Asunto(s)
Discapacidad Intelectual/genética , Mutación/genética , Espasmos Infantiles/genética , Trastornos Generalizados del Desarrollo Infantil , Estudios de Cohortes , Exoma/genética , Femenino , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/metabolismo , Predisposición Genética a la Enfermedad/genética , Humanos , Lactante , Discapacidad Intelectual/fisiopatología , Síndrome de Lennox-Gastaut , Masculino , Tasa de Mutación , N-Acetilglucosaminiltransferasas/genética , Probabilidad , Receptores de GABA-A/genética , Espasmos Infantiles/fisiopatología
8.
Brain ; 140(5): 1212-1219, 2017 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-28369215

RESUMEN

Magnetic resonance imaging has linked chronic voltage-gated potassium channel (VGKC) complex antibody-mediated limbic encephalitis with generalized hippocampal atrophy. However, autoantibodies bind to specific rodent hippocampal subfields. Here, human hippocampal subfield (subiculum, cornu ammonis 1-3, and dentate gyrus) targets of immunomodulation-treated LGI1 VGKC-complex antibody-mediated limbic encephalitis were investigated using in vivo ultra-high resolution (0.39 × 0.39 × 1.0 mm3) 7.0 T magnetic resonance imaging [n = 18 patients, 17 patients (94%) positive for LGI1 antibody and one patient negative for LGI1/CASPR2 but positive for VGKC-complex antibodies, mean age: 64.0 ± 2.55 years, median 4 years post-limbic encephalitis onset; n = 18 controls]. First, hippocampal subfield quantitative morphometry indicated significant volume loss confined to bilateral CA3 [F(1,34) = 16.87, P < 0.0001], despite hyperintense signal evident in 5 of 18 patients on presentation. Second, early and later intervention (<3 versus >3 months from symptom onset) were associated with CA3 atrophy. Third, whole-brain voxel-by-voxel morphometry revealed no significant grey matter loss. Fourth, CA3 subfield atrophy was associated with severe episodic but not semantic amnesia for postmorbid autobiographical events that was predicted by variability in CA3 volume. The results raise important questions about the links with histopathology, the impact of the observed focal atrophy on other CA3-mediated reconstructive and episodic mechanisms, and the role of potential antibody-mediated pathogenicity as part of the pathophysiology cascade in humans.


Asunto(s)
Región CA3 Hipocampal/patología , Encefalitis Límbica/patología , Canales de Potasio con Entrada de Voltaje/inmunología , Proteínas/inmunología , Adulto , Anciano , Amnesia/complicaciones , Amnesia/patología , Atrofia/complicaciones , Atrofia/patología , Autoanticuerpos/inmunología , Estudios de Casos y Controles , Femenino , Sustancia Gris/patología , Humanos , Péptidos y Proteínas de Señalización Intracelular , Encefalitis Límbica/complicaciones , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neuroimagen , Adulto Joven
9.
Curr Opin Neurol ; 30(2): 193-199, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28212175

RESUMEN

PURPOSE OF REVIEW: Epilepsy genetics is shifting from the academic pursuit of gene discovery to a clinical discipline based on molecular diagnosis and stratified medicine. We consider the latest developments in epilepsy genetics and review how gene discovery in epilepsy is influencing the clinical classification of epilepsy and informing new therapeutic approaches and drug discovery. RECENT FINDINGS: Recent studies highlighting the importance of mutation in GABA receptors, NMDA receptors, potassium channels, G-protein coupled receptors, mammalian target of rapamycin pathway and chromatin remodeling are discussed. Examples of precision medicine in epilepsy targeting gain-of-function mutations in KCNT1, GRIN2A, GRIN2D and SCN8A are presented. Potential reasons for the paucity of examples of precision medicine for loss-of-function mutations or in non-ion channel epilepsy genes are explored. We highlight how systems genetics and gene network analyses have suggested that pathways disrupted in epilepsy overlap with those of other neurodevelopmental traits including human cognition. We review how network-based computational approaches are now being applied to epilepsy drug discovery. SUMMARY: We are living in an unparalleled era of epilepsy gene discovery. Advances in clinical care from this progress are already materializing through improved clinical diagnosis and stratified medicine. The application of targeted drug repurposing based on single gene defects has shown promise for epilepsy arising from gain-of-function mutations in ion-channel subunit genes, but important barriers remain to translating these approaches to non-ion channel epilepsy genes and loss-of-function mutations. Gene network analysis offers opportunities to discover new pathways for epilepsy, to decipher epilepsy's relationship to other neurodevelopmental traits and to frame a new approach to epilepsy drug discovery.


Asunto(s)
Epilepsia/genética , Animales , Epilepsia/diagnóstico , Epilepsia/terapia , Estudios de Asociación Genética , Humanos , Mutación , Fenotipo , Canales de Potasio/genética
10.
Epilepsia ; 58(12): 2013-2024, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28960286

RESUMEN

The World Health Organization estimates that globally 2.4 million people are diagnosed with epilepsy each year. In nearly 30% of these cases, epilepsy cannot be properly controlled by antiepileptic drugs. More importantly, treatments to prevent or modify epileptogenesis do not exist. Therefore, novel therapies are urgently needed. In this respect, it is important to identify which patients will develop epilepsy and which individually tailored treatment is needed. However, currently, we have no tools to identify the patients at risk, and diagnosis of epileptogenesis remains as a major unmet medical need, which relates to lack of diagnostic biomarkers for epileptogenesis. As the epileptogenic process in humans is typically slow, the use of animal models is justified to speed up biomarker discovery. We aim to summarize recommendations for molecular biomarker research and propose a standardized procedure for biomarker discovery in rat models of epileptogenesis. The potential of many phylogenetically conserved circulating noncoding small RNAs, including microRNAs (miRNAs), as biomarkers has been explored in various brain diseases, including epilepsy. Recent studies show the feasibility of detecting miRNAs in blood in both experimental models and human epilepsy. However, the analysis of circulating miRNAs in rodent models is challenging, which relates both to the lack of standardized sampling protocols and to analysis of miRNAs. We will discuss the issues critical for preclinical plasma biomarker discovery, such as documentation, blood and brain tissue sampling and collection, plasma separation and storage, RNA extraction, quality control, and RNA detection. We propose a protocol for standardization of procedures for discovery of circulating miRNA biomarkers in rat models of epileptogenesis. Ultimately, we hope that the preclinical standardization will facilitate clinical biomarker discovery for epileptogenesis in man.


Asunto(s)
Biomarcadores/sangre , Epilepsia/sangre , MicroARNs/sangre , Ratas/fisiología , Animales , Biología Computacional , Modelos Animales de Enfermedad , Epilepsia/genética , Humanos , MicroARNs/genética , Estándares de Referencia
11.
Nucleic Acids Res ; 43(5): e33, 2015 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-25550428

RESUMEN

Methods to interpret personal genome sequences are increasingly required. Here, we report a novel framework (EvoTol) to identify disease-causing genes using patient sequence data from within protein coding-regions. EvoTol quantifies a gene's intolerance to mutation using evolutionary conservation of protein sequences and can incorporate tissue-specific gene expression data. We apply this framework to the analysis of whole-exome sequence data in epilepsy and congenital heart disease, and demonstrate EvoTol's ability to identify known disease-causing genes is unmatched by competing methods. Application of EvoTol to the human interactome revealed networks enriched for genes intolerant to protein sequence variation, informing novel polygenic contributions to human disease.


Asunto(s)
Biología Computacional/métodos , Evolución Molecular , Predisposición Genética a la Enfermedad/genética , Proteínas/genética , Secuencia de Aminoácidos/genética , Exoma/genética , Cardiopatías Congénitas/genética , Humanos , Mutación , Filogenia , Polimorfismo de Nucleótido Simple , Mapas de Interacción de Proteínas/genética , Proteínas/clasificación , Proteínas/metabolismo , Reproducibilidad de los Resultados , Análisis de Secuencia de ADN/métodos
12.
Hum Mol Genet ; 23(1): 247-58, 2014 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-23962720

RESUMEN

We present the analysis of a prospective multicentre study to investigate genetic effects on the prognosis of newly treated epilepsy. Patients with a new clinical diagnosis of epilepsy requiring medication were recruited and followed up prospectively. The clinical outcome was defined as freedom from seizures for a minimum of 12 months in accordance with the consensus statement from the International League Against Epilepsy (ILAE). Genetic effects on remission of seizures after starting treatment were analysed with and without adjustment for significant clinical prognostic factors, and the results from each cohort were combined using a fixed-effects meta-analysis. After quality control (QC), we analysed 889 newly treated epilepsy patients using 472 450 genotyped and 6.9 × 10(6) imputed single-nucleotide polymorphisms. Suggestive evidence for association (defined as Pmeta < 5.0 × 10(-7)) with remission of seizures after starting treatment was observed at three loci: 6p12.2 (rs492146, Pmeta = 2.1 × 10(-7), OR[G] = 0.57), 9p23 (rs72700966, Pmeta = 3.1 × 10(-7), OR[C] = 2.70) and 15q13.2 (rs143536437, Pmeta = 3.2 × 10(-7), OR[C] = 1.92). Genes of biological interest at these loci include PTPRD and ARHGAP11B (encoding functions implicated in neuronal development) and GSTA4 (a phase II biotransformation enzyme). Pathway analysis using two independent methods implicated a number of pathways in the prognosis of epilepsy, including KEGG categories 'calcium signaling pathway' and 'phosphatidylinositol signaling pathway'. Through a series of power curves, we conclude that it is unlikely any single common variant explains >4.4% of the variation in the outcome of newly treated epilepsy.


Asunto(s)
Epilepsia/diagnóstico , Epilepsia/genética , Estudio de Asociación del Genoma Completo , Adulto , Anticonvulsivantes/uso terapéutico , Señalización del Calcio/genética , Cromosomas Humanos Par 15 , Cromosomas Humanos Par 6 , Cromosomas Humanos Par 9 , Epilepsia/tratamiento farmacológico , Femenino , Predisposición Genética a la Enfermedad , Variación Genética , Humanos , Masculino , Persona de Mediana Edad , Fosfatidilinositoles/genética , Polimorfismo de Nucleótido Simple , Pronóstico , Estudios Prospectivos , Resultado del Tratamiento , Adulto Joven
13.
Epilepsy Behav ; 54: 117-27, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26708060

RESUMEN

Cognitive dysfunction is a common comorbidity in people with epilepsy, but its causes remain unclear. It may be related to the etiology of the disorder, the consequences of seizures, or the effects of antiepileptic drug treatment. Genetics may also play a contributory role. We investigated the influence of variants in the genes encoding neuron-restrictive silencer factor (NRSF) and brain-derived neurotrophic factor (BDNF), proteins previously associated with cognition and epilepsy, on cognitive function in people with newly diagnosed epilepsy. A total of 82 patients who had previously undergone detailed neuropsychological assessment were genotyped for single nucleotide polymorphisms (SNPs) across the NRSF and BDNF genes. Putatively functional SNPs were included in a genetic association analysis with specific cognitive domains, including memory, psychomotor speed, and information processing. Cross-sectional and longitudinal designs were used to explore genetic influences on baseline cognition at diagnosis and change from baseline over the first year since diagnosis, respectively. We found a statistically significant association between genotypic variation and memory function at both baseline (NRSF: rs1105434, rs2227902 and BDNF: rs1491850, rs2030324, rs11030094) and in our longitudinal analysis (NRSF: rs2227902 and BDNF: rs12273363). Psychomotor speed was also associated with genotype (NRSF rs3796529) in the longitudinal assessment. In line with our previous work on general cognitive function in the healthy aging population, we observed an additive interaction between risk alleles for the NRSF rs2227902 (G) and BDNF rs6265 (A) polymorphisms which was again consistent with a significantly greater decline in delayed recall over the first year since diagnosis. These findings support a role for the NRSF-BDNF pathway in the modulation of cognitive function in patients with newly diagnosed epilepsy.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/genética , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/genética , Epilepsia/diagnóstico , Epilepsia/genética , Polimorfismo de Nucleótido Simple/genética , Adolescente , Adulto , Anciano , Trastornos del Conocimiento/epidemiología , Estudios Transversales , Epilepsia/epidemiología , Femenino , Marcadores Genéticos/genética , Pruebas Genéticas/métodos , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Proteínas Represoras , Adulto Joven
14.
Am J Hum Genet ; 91(6): 1011-21, 2012 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-23217325

RESUMEN

Estimation of narrow-sense heritability, h(2), from genome-wide SNPs genotyped in unrelated individuals has recently attracted interest and offers several advantages over traditional pedigree-based methods. With the use of this approach, it has been estimated that over half the heritability of human height can be attributed to the ~300,000 SNPs on a genome-wide genotyping array. In comparison, only 5%-10% can be explained by SNPs reaching genome-wide significance. We investigated via simulation the validity of several key assumptions underpinning the mixed-model analysis used in SNP-based h(2) estimation. Although we found that the method is reasonably robust to violations of four key assumptions, it can be highly sensitive to uneven linkage disequilibrium (LD) between SNPs: contributions to h(2) are overestimated from causal variants in regions of high LD and are underestimated in regions of low LD. The overall direction of the bias can be up or down depending on the genetic architecture of the trait, but it can be substantial in realistic scenarios. We propose a modified kinship matrix in which SNPs are weighted according to local LD. We show that this correction greatly reduces the bias and increases the precision of h(2) estimates. We demonstrate the impact of our method on the first seven diseases studied by the Wellcome Trust Case Control Consortium. Our LD adjustment revises downward the h(2) estimate for immune-related diseases, as expected because of high LD in the major-histocompatibility region, but increases it for some nonimmune diseases. To calculate our revised kinship matrix, we developed LDAK, software for computing LD-adjusted kinships.


Asunto(s)
Estudio de Asociación del Genoma Completo , Modelos Genéticos , Herencia Multifactorial/genética , Polimorfismo de Nucleótido Simple , Algoritmos , Simulación por Computador , Genoma Humano , Genotipo , Humanos , Desequilibrio de Ligamiento , Linaje
15.
Brain ; 137(Pt 10): 2680-9, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25063994

RESUMEN

Epilepsy is a disease with substantial missing heritability; despite its high genetic component, genetic association studies have had limited success detecting common variants which influence susceptibility. In this paper, we reassess the role of common variants on epilepsy using extensions of heritability analysis. Our data set consists of 1258 UK patients with epilepsy, of which 958 have focal epilepsy, and 5129 population control subjects, with genotypes recorded for over 4 million common single nucleotide polymorphisms. Firstly, we show that on the liability scale, common variants collectively explain at least 26% (standard deviation 5%) of phenotypic variation for all epilepsy and 27% (standard deviation 5%) for focal epilepsy. Secondly we provide a new method for estimating the number of causal variants for complex traits; when applied to epilepsy, our most optimistic estimate suggests that at least 400 variants influence disease susceptibility, with potentially many thousands. Thirdly, we use bivariate analysis to assess how similar the genetic architecture of focal epilepsy is to that of non-focal epilepsy; we demonstrate both significant differences (P = 0.004) and significant similarities (P = 0.01) between the two subtypes, indicating that although the clinical definition of focal epilepsy does identify a genetically distinct epilepsy subtype, there is also scope to improve the classification of epilepsy by incorporating genotypic information. Lastly, we investigate the potential value in using genetic data to diagnose epilepsy following a single epileptic seizure; we find that a prediction model explaining 10% of phenotypic variation could have clinical utility for deciding which single-seizure individuals are likely to benefit from immediate anti-epileptic drug therapy.


Asunto(s)
Epilepsia/genética , Edad de Inicio , Algoritmos , Área Bajo la Curva , Pueblo Asiatico , Epilepsia/fisiopatología , Sitios Genéticos , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Genotipo , Técnicas de Genotipaje , Humanos , Modelos Estadísticos , Polimorfismo de Nucleótido Simple , Población , Carácter Cuantitativo Heredable , Curva ROC , Convulsiones/genética , Convulsiones/fisiopatología , Población Blanca
16.
N Engl J Med ; 364(12): 1134-43, 2011 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-21428769

RESUMEN

BACKGROUND: Carbamazepine causes various forms of hypersensitivity reactions, ranging from maculopapular exanthema to severe blistering reactions. The HLA-B*1502 allele has been shown to be strongly correlated with carbamazepine-induced Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS-TEN) in the Han Chinese and other Asian populations but not in European populations. METHODS: We performed a genomewide association study of samples obtained from 22 subjects with carbamazepine-induced hypersensitivity syndrome, 43 subjects with carbamazepine-induced maculopapular exanthema, and 3987 control subjects, all of European descent. We tested for an association between disease and HLA alleles through proxy single-nucleotide polymorphisms and imputation, confirming associations by high-resolution sequence-based HLA typing. We replicated the associations in samples from 145 subjects with carbamazepine-induced hypersensitivity reactions. RESULTS: The HLA-A*3101 allele, which has a prevalence of 2 to 5% in Northern European populations, was significantly associated with the hypersensitivity syndrome (P=3.5×10(-8)). An independent genomewide association study of samples from subjects with maculopapular exanthema also showed an association with the HLA-A*3101 allele (P=1.1×10(-6)). Follow-up genotyping confirmed the variant as a risk factor for the hypersensitivity syndrome (odds ratio, 12.41; 95% confidence interval [CI], 1.27 to 121.03), maculopapular exanthema (odds ratio, 8.33; 95% CI, 3.59 to 19.36), and SJS-TEN (odds ratio, 25.93; 95% CI, 4.93 to 116.18). CONCLUSIONS: The presence of the HLA-A*3101 allele was associated with carbamazepine-induced hypersensitivity reactions among subjects of Northern European ancestry. The presence of the allele increased the risk from 5.0% to 26.0%, whereas its absence reduced the risk from 5.0% to 3.8%. (Funded by the U.K. Department of Health and others.).


Asunto(s)
Anticonvulsivantes/efectos adversos , Carbamazepina/efectos adversos , Hipersensibilidad a las Drogas/genética , Antígenos HLA-A/genética , Población Blanca/genética , Anticonvulsivantes/uso terapéutico , Carbamazepina/uso terapéutico , Exantema/inducido químicamente , Exantema/genética , Estudio de Asociación del Genoma Completo , Genotipo , Prueba de Histocompatibilidad , Humanos , Polimorfismo de Nucleótido Simple , Síndrome de Stevens-Johnson/inducido químicamente , Síndrome de Stevens-Johnson/genética
17.
Brain ; 136(Pt 10): 3151-62, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24014519

RESUMEN

Voltage-gated potassium channel complex antibodies, particularly those directed against leucine-rich glioma inactivated 1, are associated with a common form of limbic encephalitis that presents with cognitive impairment and seizures. Faciobrachial dystonic seizures have recently been reported as immunotherapy-responsive, brief, frequent events that often predate the cognitive impairment associated with this limbic encephalitis. However, these observations were made from a retrospective study without serial cognitive assessments. Here, we undertook the first prospective study of faciobrachial dystonic seizures with serial assessments of seizure frequencies, cognition and antibodies in 10 cases identified over 20 months. We hypothesized that (i) faciobrachial dystonic seizures would show a differential response to anti-epileptic drugs and immunotherapy; and that (ii) effective treatment of faciobrachial dystonic seizures would accelerate recovery and prevent the development of cognitive impairment. The 10 cases expand both the known age at onset (28 to 92 years, median 68) and clinical features, with events of longer duration, simultaneously bilateral events, prominent automatisms, sensory aura, and post-ictal fear and speech arrest. Ictal epileptiform electroencephalographic changes were present in three cases. All 10 cases were positive for voltage-gated potassium channel-complex antibodies (346-4515 pM): nine showed specificity for leucine-rich glioma inactivated 1. Seven cases had normal clinical magnetic resonance imaging, and the cerebrospinal fluid examination was unremarkable in all seven tested. Faciobrachial dystonic seizures were controlled more effectively with immunotherapy than anti-epileptic drugs (P = 0.006). Strikingly, in the nine cases who remained anti-epileptic drug refractory for a median of 30 days (range 11-200), the addition of corticosteroids was associated with cessation of faciobrachial dystonic seizures within 1 week in three and within 2 months in six cases. Voltage-gated potassium channel-complex antibodies persisted in the four cases with relapses of faciobrachial dystonic seizures during corticosteroid withdrawal. Time to recovery of baseline function was positively correlated with time to immunotherapy (r = 0.74; P = 0.03) but not time to anti-epileptic drug administration (r = 0.55; P = 0.10). Of 10 cases, the eight cases who received anti-epileptic drugs (n = 3) or no treatment (n = 5) all developed cognitive impairment. By contrast, the two who did not develop cognitive impairment received immunotherapy to treat their faciobrachial dystonic seizures (P = 0.02). In eight cases without clinical magnetic resonance imaging evidence of hippocampal signal change, cross-sectional volumetric magnetic resonance imaging post-recovery, after accounting for age and head size, revealed cases (n = 8) had smaller brain volumes than healthy controls (n = 13) (P < 0.001). In conclusion, faciobrachial dystonic seizures can be prospectively identified as a form of epilepsy with an expanding phenotype. Immunotherapy is associated with excellent control of the frequently anti-epileptic drug refractory seizures, hastens time to recovery, and may prevent the subsequent development of cognitive impairment observed in this study.


Asunto(s)
Anticuerpos/uso terapéutico , Trastornos del Conocimiento/prevención & control , Convulsiones/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Electroencefalografía/métodos , Femenino , Humanos , Encefalitis Límbica/tratamiento farmacológico , Encefalitis Límbica/fisiopatología , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Fenotipo , Estudios Prospectivos , Convulsiones/inmunología , Convulsiones/fisiopatología , Resultado del Tratamiento
18.
Cureus ; 16(3): e57196, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38681441

RESUMEN

Background The consumption of recreational and medicinal cannabis in the United States continues to increase. Understanding the effects of cannabis in patients undergoing elective primary breast augmentation (EPBA) is of paramount importance with the expanding rates of reported cannabis consumption. Objectives This study aims to analyze the peri-operative impact of cannabis use in conjunction with EPBA in a single-surgeon practice in San Francisco, California. Methods A retrospective chart review was performed of 134 adult female patients undergoing EPBA from August 2018 to January 2022 within a single-surgeon practice plastic surgery office. Cannabis use was self-reported as current use or former use. Cohorts were grouped as cannabis users and cannabis non-users. Results Of the 134 patient charts identified for analysis, 58 (43.3%) reported cannabis use. Cannabis users were significantly younger than cannabis non-users (26.8 years versus 31.5 years, P<0.001). No significant differences were found between groups among intra-operative blood loss, post-operative complication rates, post-operative narcotic use, or intra-operative anesthetic requirements. The incidence of adverse events, including wound breakdown, skin necrosis, and capsular contracture requiring reoperation, did not differ significantly between cannabis users and cannabis non-user groups. Ninety-six percent of patients had their implants placed subpectorally, and all procedures were done using a Keller funnel. Eighty-three percent of patients had Sientra implants, and 96% of all implants were silicone gel implants. All procedures were done under general anesthesia. Patients were followed for up to two years. Discussion This review found no significant differences in peri-operative and post-operative outcomes between cannabis users and cannabis non-users.

19.
Am J Hum Genet ; 86(5): 707-18, 2010 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-20398883

RESUMEN

Deletions at 16p13.11 are associated with schizophrenia, mental retardation, and most recently idiopathic generalized epilepsy. To evaluate the role of 16p13.11 deletions, as well as other structural variation, in epilepsy disorders, we used genome-wide screens to identify copy number variation in 3812 patients with a diverse spectrum of epilepsy syndromes and in 1299 neurologically-normal controls. Large deletions (> 100 kb) at 16p13.11 were observed in 23 patients, whereas no control had a deletion greater than 16 kb. Patients, even those with identically sized 16p13.11 deletions, presented with highly variable epilepsy phenotypes. For a subset of patients with a 16p13.11 deletion, we show a consistent reduction of expression for included genes, suggesting that haploinsufficiency might contribute to pathogenicity. We also investigated another possible mechanism of pathogenicity by using hybridization-based capture and next-generation sequencing of the homologous chromosome for ten 16p13.11-deletion patients to look for unmasked recessive mutations. Follow-up genotyping of suggestive polymorphisms failed to identify any convincing recessive-acting mutations in the homologous interval corresponding to the deletion. The observation that two of the 16p13.11 deletions were larger than 2 Mb in size led us to screen for other large deletions. We found 12 additional genomic regions harboring deletions > 2 Mb in epilepsy patients, and none in controls. Additional evaluation is needed to characterize the role of these exceedingly large, non-locus-specific deletions in epilepsy. Collectively, these data implicate 16p13.11 and possibly other large deletions as risk factors for a wide range of epilepsy disorders, and they appear to point toward haploinsufficiency as a contributor to the pathogenicity of deletions.


Asunto(s)
Cromosomas Humanos Par 16 , Susceptibilidad a Enfermedades , Epilepsia/genética , Mutación , Eliminación de Secuencia , Humanos , Hibridación de Ácido Nucleico/genética , Síndrome
20.
Artículo en Inglés | MEDLINE | ID: mdl-37582616

RESUMEN

OBJECTIVES: Leucine-rich glioma-inactivated 1 (LGI1) encephalitis and IgG4-related disease (IgG4RD) have traditionally been regarded as 2 distinct disease entities. METHODS: We detail the presentation, investigations, and management of a patient who showed typical signs and symptoms of LGI1 encephalitis and also found to possess pancreatic changes and a serum profile in keeping with IgG4RD. RESULTS: Serum and CSF analyses at presentation showed a significant hyponatraemia (117 mmol/L), elevated IgG4 concentration (1.73 g/L), and the presence of LGI1 antibodies. MRI revealed symmetrical diffuse T2-weighted hyperintensity and mild swelling throughout both medial temporal lobes. CT of the chest, abdomen and pelvis revealed an edematous, bulky pancreas with loss of lobulation, typical for IgG4RD. A glucocorticoid weaning regimen was commenced, facilitated by 2 rituximab infusions, with the patient showing an effective treatment response. HLA testing confirmed the presence of HLA DRB1 and HLA DQB1 risk alleles. DISCUSSION: This case suggests that there may be shared mechanisms between LGI1 encephalitis and IgG4RD, supported by common risk HLA associations and treatment strategies/responses. To our knowledge, this represents the first instance that LGI1 encephalitis and IgG4RD have been reported in the same patient and emphasizes the continued development of our understanding of the wide range of IgG4-mediated conditions.


Asunto(s)
Encefalitis , Enfermedad Relacionada con Inmunoglobulina G4 , Humanos , Autoanticuerpos , Encefalitis/diagnóstico , Inmunoglobulina G , Enfermedad Relacionada con Inmunoglobulina G4/complicaciones , Enfermedad Relacionada con Inmunoglobulina G4/diagnóstico , Péptidos y Proteínas de Señalización Intracelular , Leucina
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA