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1.
Cell ; 163(3): 541-2, 2015 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-26496599

RESUMO

To investigate the fundamental question of how nervous systems encode, organize, and sequence behaviors, Kato et al. imaged neural activity with cellular resolution across the brain of the worm Caenorhabditis elegans. Locomotion behavior seems to be continuously represented by cyclical patterns of distributed neural activity that are present even in immobilized animals.


Assuntos
Caenorhabditis elegans/citologia , Caenorhabditis elegans/fisiologia , Animais
2.
Nature ; 579(7798): 256-259, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32132709

RESUMO

Most cortical synapses are local and excitatory. Local recurrent circuits could implement amplification, allowing pattern completion and other computations1-4. Cortical circuits contain subnetworks that consist of neurons with similar receptive fields and increased connectivity relative to the network average5,6. Cortical neurons that encode different types of information are spatially intermingled and distributed over large brain volumes5-7, and this complexity has hindered attempts to probe the function of these subnetworks by perturbing them individually8. Here we use computational modelling, optical recordings and manipulations to probe the function of recurrent coupling in layer 2/3 of the mouse vibrissal somatosensory cortex during active tactile discrimination. A neural circuit model of layer 2/3 revealed that recurrent excitation enhances sensory signals by amplification, but only for subnetworks with increased connectivity. Model networks with high amplification were sensitive to damage: loss of a few members of the subnetwork degraded stimulus encoding. We tested this prediction by mapping neuronal selectivity7 and photoablating9,10 neurons with specific selectivity. Ablation of a small proportion of layer 2/3 neurons (10-20, less than 5% of the total) representing touch markedly reduced responses in the spared touch representation, but not in other representations. Ablations most strongly affected neurons with stimulus responses that were similar to those of the ablated population, which is also consistent with network models. Recurrence among cortical neurons with similar selectivity therefore drives input-specific amplification during behaviour.


Assuntos
Modelos Neurológicos , Neurônios/fisiologia , Córtex Somatossensorial/fisiologia , Animais , Simulação por Computador , Camundongos , Tato/fisiologia
3.
J Biol Chem ; 300(1): 105565, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38103642

RESUMO

The biochemical SRX (super-relaxed) state of myosin has been defined as a low ATPase activity state. This state can conserve energy when the myosin is not recruited for muscle contraction. The SRX state has been correlated with a structurally defined ordered (versus disordered) state of muscle thick filaments. The two states may be linked via a common interacting head motif (IHM) where the two heads of heavy meromyosin (HMM), or myosin, fold back onto each other and form additional contacts with S2 and the thick filament. Experimental observations of the SRX, IHM, and the ordered form of thick filaments, however, do not always agree, and result in a series of unresolved paradoxes. To address these paradoxes, we have reexamined the biochemical measurements of the SRX state for porcine cardiac HMM. In our hands, the commonly employed mantATP displacement assay was unable to quantify the population of the SRX state with all data fitting very well by a single exponential. We further show that mavacamten inhibits the basal ATPases of both porcine ventricle HMM and S1 (Ki, 0.32 and 1.76 µM respectively) while dATP activates HMM cooperatively without any evidence of an SRX state. A combination of our experimental observations and theories suggests that the displacement of mantATP in purified proteins is not a reliable assay to quantify the SRX population. This means that while the structurally defined IHM and ordered thick filaments clearly exist, great care must be employed when using the mantATP displacement assay.


Assuntos
Trifosfato de Adenosina , Ensaios Enzimáticos , Miosina não Muscular Tipo IIA , Suínos , ortoaminobenzoatos , Animais , Adenosina Trifosfatases/antagonistas & inibidores , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/metabolismo , Motivos de Aminoácidos , Benzilaminas/farmacologia , Ensaios Enzimáticos/métodos , Ensaios Enzimáticos/normas , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/enzimologia , Ventrículos do Coração/metabolismo , Contração Miocárdica , Subfragmentos de Miosina/química , Subfragmentos de Miosina/metabolismo , Miosina não Muscular Tipo IIA/química , Miosina não Muscular Tipo IIA/metabolismo , ortoaminobenzoatos/metabolismo , Uracila/análogos & derivados , Uracila/farmacologia
4.
Circ Res ; 133(5): 430-443, 2023 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-37470183

RESUMO

BACKGROUND: Modulating myosin function is a novel therapeutic approach in patients with cardiomyopathy. Danicamtiv is a novel myosin activator with promising preclinical data that is currently in clinical trials. While it is known that danicamtiv increases force and cardiomyocyte contractility without affecting calcium levels, detailed mechanistic studies regarding its mode of action are lacking. METHODS: Permeabilized porcine cardiac tissue and myofibrils were used for X-ray diffraction and mechanical measurements. A mouse model of genetic dilated cardiomyopathy was used to evaluate the ability of danicamtiv to correct the contractile deficit. RESULTS: Danicamtiv increased force and calcium sensitivity via increasing the number of myosins in the ON state and slowing cross-bridge turnover. Our detailed analysis showed that inhibition of ADP release results in decreased cross-bridge turnover with cross bridges staying attached longer and prolonging myofibril relaxation. Danicamtiv corrected decreased calcium sensitivity in demembranated tissue, abnormal twitch magnitude and kinetics in intact cardiac tissue, and reduced ejection fraction in the whole organ. CONCLUSIONS: As demonstrated by the detailed studies of Danicamtiv, increasing myosin recruitment and altering cross-bridge cycling are 2 mechanisms to increase force and calcium sensitivity in cardiac muscle. Myosin activators such as Danicamtiv can treat the causative hypocontractile phenotype in genetic dilated cardiomyopathy.


Assuntos
Cardiomiopatia Dilatada , Camundongos , Animais , Suínos , Cardiomiopatia Dilatada/tratamento farmacológico , Cálcio/fisiologia , Miocárdio , Miosinas , Miócitos Cardíacos , Cardiotônicos
5.
Hum Mol Genet ; 31(14): 2307-2316, 2022 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-35137044

RESUMO

Hypothalamic hamartoma with gelastic seizures is a well-established cause of drug-resistant epilepsy in early life. The development of novel surgical techniques has permitted the genomic interrogation of hypothalamic hamartoma tissue. This has revealed causative mosaic variants within GLI3, OFD1 and other key regulators of the sonic-hedgehog pathway in a minority of cases. Sonic-hedgehog signalling proteins localize to the cellular organelle primary cilia. We therefore explored the hypothesis that cilia gene variants may underlie hitherto unsolved cases of sporadic hypothalamic hamartoma. We performed high-depth exome sequencing and chromosomal microarray on surgically resected hypothalamic hamartoma tissue and paired leukocyte-derived DNA from 27 patients. We searched for both germline and somatic variants under both dominant and bi-allelic genetic models. In hamartoma-derived DNA of seven patients we identified bi-allelic (one germline, one somatic) variants within one of four cilia genes-DYNC2I1, DYNC2H1, IFT140 or SMO. In eight patients, we identified single somatic variants in the previously established hypothalamic hamartoma disease genes GLI3 or OFD1. Overall, we established a plausible molecular cause for 15/27 (56%) patients. Here, we expand the genetic architecture beyond single variants within dominant disease genes that cause sporadic hypothalamic hamartoma to bi-allelic (one germline/one somatic) variants, implicate three novel cilia genes and reconceptualize the disorder as a ciliopathy.


Assuntos
Ciliopatias , Hamartoma , Doenças Hipotalâmicas , Ciliopatias/genética , Hamartoma/genética , Proteínas Hedgehog/metabolismo , Humanos , Doenças Hipotalâmicas/complicações , Doenças Hipotalâmicas/genética , Imageamento por Ressonância Magnética
6.
Am J Hum Genet ; 106(4): 559-569, 2020 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-32197075

RESUMO

Negative regulator of reactive oxygen species (NRROS) is a leucine-rich repeat-containing protein that uniquely associates with latent transforming growth factor beta-1 (TGF- ß1) and anchors it on the cell surface; this anchoring is required for activation of TGF-ß1 in macrophages and microglia. We report six individuals from four families with bi-allelic variants in NRROS. All affected individuals had neurodegenerative disease with refractory epilepsy, developmental regression, and reduced white matter volume with delayed myelination. The clinical course in affected individuals began with normal development or mild developmental delay, and the onset of seizures occurred within the first year of life, followed by developmental regression. Intracranial calcification was detected in three individuals. The phenotypic features in affected individuals are consistent with those observed in the Nrros knockout mouse, and they overlap with those seen in the human condition associated with TGF-ß1 deficiency. The disease-causing NRROS variants involve two significant functional NRROS domains. These variants result in aberrant NRROS proteins with impaired ability to anchor latent TGF-ß1 on the cell surface. Using confocal microscopy in HEK293T cells, we demonstrate that wild-type and mutant NRROS proteins co-localize with latent TGF-ß1 intracellularly. However, using flow cytometry, we show that our mutant NRROS proteins fail to anchor latent TGF-ß1 at the cell surface in comparison to wild-type NRROS. Moreover, wild-type NRROS rescues the defect of our disease-associated mutants in presenting latent TGF-ß1 to the cell surface. Taken together, our findings suggest that loss of NRROS function causes a severe childhood-onset neurodegenerative condition with features suggestive of a disordered response to inflammation.


Assuntos
Encefalopatias/genética , Calcinose/genética , Variação Genética/genética , Proteínas de Ligação a TGF-beta Latente/genética , Doenças Neurodegenerativas/genética , Fator de Crescimento Transformador beta1/genética , Alelos , Feminino , Células HEK293 , Humanos , Lactente , Macrófagos/patologia , Masculino , Microglia/patologia
7.
Am J Med Genet A ; 191(6): 1599-1606, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36896486

RESUMO

Mitochondrial respiratory chain disorders (MRC) are amongst the most common group of inborn errors of metabolism. MRC, of which complex I deficiency accounts for approximately a quarter, are very diverse, causing a wide range of clinical problems and can be difficult to diagnose. We report an illustrative MRC case whose diagnosis was elusive. Clinical signs included failure to thrive caused by recurrent vomiting, hypotonia and progressive loss of motor milestones. Initial brain imaging suggested Leigh syndrome but without expected diffusion restriction. Muscle respiratory chain enzymology was unremarkable. Whole-genome sequencing identified a maternally inherited NDUFV1 missense variant [NM_007103.4 (NDUFV1):c.1157G > A; p.(Arg386His)] and a paternally inherited synonymous variant [NM_007103.4 (NDUFV1):c.1080G > A; (p.Ser360=)]. RNA sequencing demonstrated aberrant splicing. This case emphasizes the diagnostic odyssey of a patient in whom a confirmed diagnosis was elusive because of atypical features and normal muscle respiratory chain enzyme (RCE) activities, along with a synonymous variant, which are often filtered out from genomic analyses. It also illustrates the following points: (1) complete resolution of magnetic resonance imaging changes may be part of the picture in mitochondrial disease; (2) analysis for synonymous variants is important for undiagnosed patients; and (3) RNA-seq is a powerful tool to demonstrate pathogenicity of putative splicing variants.


Assuntos
Imageamento por Ressonância Magnética , Músculos , Humanos , RNA-Seq , Sequenciamento Completo do Genoma , Encéfalo , Complexo I de Transporte de Elétrons/genética
8.
Endocr Pract ; 29(10): 811-821, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37236353

RESUMO

OBJECTIVE: The incidence of thyroid cancer has significantly increased in recent decades. Although most thyroid cancers are small and carry an excellent prognosis, a subset of patients present with advanced thyroid cancer, which is associated with increased rates of morbidity and mortality. The management of thyroid cancer requires a thoughtful individualized approach to optimize oncologic outcomes and minimize morbidity associated with treatment. Because endocrinologists usually play a key role in the initial diagnosis and evaluation of thyroid cancers, a thorough understanding of the critical components of the preoperative evaluation facilitates the development of a timely and comprehensive management plan. The following review outlines considerations in the preoperative evaluation of patients with thyroid cancer. METHODS: A clinical review based on current literature was generated by a multidisciplinary author panel. RESULTS: A review of considerations in the preoperative evaluation of thyroid cancer is provided. The topic areas include initial clinical evaluation, imaging modalities, cytologic evaluation, and the evolving role of mutational testing. Special considerations in the management of advanced thyroid cancer are discussed. CONCLUSION: Thorough and thoughtful preoperative evaluation is critical for formulating an appropriate treatment strategy in the management of thyroid cancer.


Assuntos
Neoplasias da Glândula Tireoide , Humanos , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/cirurgia , Prognóstico
9.
Ecol Lett ; 25(6): 1510-1520, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35546256

RESUMO

Forests are currently a substantial carbon sink globally. Many climate change mitigation strategies leverage forest preservation and expansion, but rely on forests storing carbon for decades to centuries. Yet climate-driven disturbances pose critical risks to the long-term stability of forest carbon. We quantify the climate drivers that influence wildfire and climate stress-driven tree mortality, including a separate insect-driven tree mortality, for the contiguous United States for current (1984-2018) and project these future disturbance risks over the 21st century. We find that current risks are widespread and projected to increase across different emissions scenarios by a factor of >4 for fire and >1.3 for climate-stress mortality. These forest disturbance risks highlight pervasive climate-sensitive disturbance impacts on US forests and raise questions about the risk management approach taken by forest carbon offset policies. Our results provide US-wide risk maps of key climate-sensitive disturbances for improving carbon cycle modeling, conservation and climate policy.


Assuntos
Incêndios , Florestas , Animais , Carbono , Mudança Climática , Insetos , Árvores , Estados Unidos
10.
Glob Chang Biol ; 28(4): 1433-1445, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34668621

RESUMO

Carbon offsets are widely used by individuals, corporations, and governments to mitigate their greenhouse gas emissions on the assumption that offsets reflect equivalent climate benefits achieved elsewhere. These climate-equivalence claims depend on offsets providing real and additional climate benefits beyond what would have happened, counterfactually, without the offsets project. Here, we evaluate the design of California's prominent forest carbon offsets program and demonstrate that its climate-equivalence claims fall far short on the basis of directly observable evidence. By design, California's program awards large volumes of offset credits to forest projects with carbon stocks that exceed regional averages. This paradigm allows for adverse selection, which could occur if project developers preferentially select forests that are ecologically distinct from unrepresentative regional averages. By digitizing and analyzing comprehensive offset project records alongside detailed forest inventory data, we provide direct evidence that comparing projects against coarse regional carbon averages has led to systematic over-crediting of 30.0 million tCO2 e (90% CI: 20.5-38.6 million tCO2 e) or 29.4% of the credits we analyzed (90% CI: 20.1%-37.8%). These excess credits are worth an estimated $410 million (90% CI: $280-$528 million) at recent market prices. Rather than improve forest management to store additional carbon, California's forest offsets program creates incentives to generate offset credits that do not reflect real climate benefits.


Assuntos
Carbono , Gases de Efeito Estufa , California , Conservação dos Recursos Naturais , Florestas , Humanos
11.
Epilepsia ; 63(4): 974-991, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35179230

RESUMO

OBJECTIVE: Epilepsy is common in patients with PIGN diseases due to biallelic variants; however, limited epilepsy phenotyping data have been reported. We describe the epileptology of PIGN encephalopathy. METHODS: We recruited patients with epilepsy due to biallelic PIGN variants and obtained clinical data regarding age at seizure onset/offset and semiology, development, medical history, examination, electroencephalogram, neuroimaging, and treatment. Seizure and epilepsy types were classified. RESULTS: Twenty six patients (13 female) from 26 families were identified, with mean age 7 years (range = 1 month to 21 years; three deceased). Abnormal development at seizure onset was present in 25 of 26. Developmental outcome was most frequently profound (14/26) or severe (11/26). Patients presented with focal motor (12/26), unknown onset motor (5/26), focal impaired awareness (1/26), absence (2/26), myoclonic (2/26), myoclonic-atonic (1/26), and generalized tonic-clonic (2/26) seizures. Twenty of 26 were classified as developmental and epileptic encephalopathy (DEE): 55% (11/20) focal DEE, 30% (6/20) generalized DEE, and 15% (3/20) combined DEE. Six had intellectual disability and epilepsy (ID+E): two generalized and four focal epilepsy. Mean age at seizure onset was 13 months (birth to 10 years), with a lower mean onset in DEE (7 months) compared with ID+E (33 months). Patients with DEE had drug-resistant epilepsy, compared to 4/6 ID+E patients, who were seizure-free. Hyperkinetic movement disorder occurred in 13 of 26 patients. Twenty-seven of 34 variants were novel. Variants were truncating (n = 7), intronic and predicted to affect splicing (n = 7), and missense or inframe indels (n = 20, of which 11 were predicted to affect splicing). Seven variants were recurrent, including p.Leu311Trp in 10 unrelated patients, nine with generalized seizures, accounting for nine of the 11 patients in this cohort with generalized seizures. SIGNIFICANCE: PIGN encephalopathy is a complex autosomal recessive disorder associated with a wide spectrum of epilepsy phenotypes, typically with substantial profound to severe developmental impairment.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia , Deficiência Intelectual , Eletroencefalografia , Epilepsia/diagnóstico por imagem , Epilepsia/genética , Feminino , Humanos , Deficiência Intelectual/diagnóstico por imagem , Deficiência Intelectual/genética , Fenótipo , Convulsões/genética
12.
Br J Clin Pharmacol ; 88(7): 3101-3113, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35261078

RESUMO

There is international interest for consensus advice for prescribers working in the field of drug resistant epilepsy intending to trial potential therapies that are nonregistered or off-label. Cannabinoids are one such therapy. In 2017, the New South Wales State Government (Australia) set up a cannabinoid prescribing guidance service for a wide variety of indications, based on known pharmacology together with the relevant new literature as it became available. Increasing interest in cannabis medicines use outside this State over the following 5 years together with a paucity of registration-standard clinical trials, lack of information around dosing issues, drug interactions and biological plausibility meant there remained a large unmet need for such advice. To address the unmet need in epilepsy, and until medicines were registered or regulator quality data were available, it was agreed to bring together a working group comprising paediatric and adult epilepsy specialists, clinical pharmacists., clinical pharmacologists and cannabis researchers from across Australia to develop interim consensus advice for prescribers. Although interim, this consensus advice addresses much of the current practice gap by providing an informed overview of the different cannabis medicines currently available for use in the treatment of epilepsy in paediatric and adult settings, with information on dose, drug interactions, toxicity, type of seizure and frequency of symptom relief. As such it supplements the limited evidence currently available from clinical trials with experience from front-line practice. It is expected that this consensus advice will be updated as new evidence emerges and will provide guidance for a subsequent Guideline.


Assuntos
Canabinoides , Cannabis , Epilepsia , Alucinógenos , Adulto , Analgésicos/uso terapêutico , Austrália , Canabinoides/farmacologia , Criança , Epilepsia/tratamento farmacológico , Humanos , Convulsões/tratamento farmacológico
13.
Nat Methods ; 15(12): 1117-1125, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30504888

RESUMO

Whole-brain imaging allows for comprehensive functional mapping of distributed neural pathways, but neuronal perturbation experiments are usually limited to targeting predefined regions or genetically identifiable cell types. To complement whole-brain measures of activity with brain-wide manipulations for testing causal interactions, we introduce a system that uses measured activity patterns to guide optical perturbations of any subset of neurons in the same fictively behaving larval zebrafish. First, a light-sheet microscope collects whole-brain data that are rapidly analyzed by a distributed computing system to generate functional brain maps. On the basis of these maps, the experimenter can then optically ablate neurons and image activity changes across the brain. We applied this method to characterize contributions of behaviorally tuned populations to the optomotor response. We extended the system to optogenetically stimulate arbitrary subsets of neurons during whole-brain imaging. These open-source methods enable delineating the contributions of neurons to brain-wide circuit dynamics and behavior in individual animals.


Assuntos
Comportamento Animal/fisiologia , Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Larva/fisiologia , Neurônios/fisiologia , Sistemas On-Line , Peixe-Zebra/fisiologia , Animais , Encéfalo/citologia , Vias Neurais , Neurônios/citologia , Natação
14.
Calcif Tissue Int ; 109(2): 139-146, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33829290

RESUMO

This study aimed to investigate the prevalence of fractures and non-fracture injuries, including associated risk factors, in children with epilepsy prescribed antiseizure medications (ASM). A controlled, cross-sectional study was conducted in a hospital outpatient setting, comparing children with epilepsy prescribed ASMs with their non-epileptic siblings. Information was collected by questionnaire included history of fractures, non-fracture injuries and epilepsy, comorbidities and ASM use. 261 participants completed the questionnaire, 133 children with epilepsy (aged 10.7 ± 3.5 years, mean ± SD) and 128 siblings (10.1 ± 3.7 years). There were 49 non-seizure-related fractures in 34 ASM patients while prescribed ASMs, compared with 21 lifetime fractures in 15 controls, giving a 2.7 (95% CI 1.3-5.3, p = 0.007) times greater fracture prevalence in children treated with ASMs compared to healthy siblings. The rates of non-fracture injuries were similar across groups, except that concussion was more common in children taking ASMs (9.0% vs 1.6%, p = 0.026). Duration of ASM use and generalized tonic-clonic seizures (GTCS) were independent predictors of fractures (OR 1.55; 95% CI 1.03-2.31, p = 0.03; OR 2.50; 95% CI 1.05-5.94, p = 0.04, respectively). Fewer than 20% of participants and/or their families were aware that ASM use was related to bone health. Children with epilepsy treated with ASMs had a higher fracture prevalence than their sibling controls. Duration of ASM treatment and GTCS were associated with fracture risk. Longitudinal prospective studies are required to further explore risk and the direct impact of epilepsy on bone health.


Assuntos
Epilepsia , Fraturas Ósseas , Anticonvulsivantes/efeitos adversos , Criança , Estudos Transversais , Epilepsia/complicações , Epilepsia/tratamento farmacológico , Epilepsia/epidemiologia , Fraturas Ósseas/tratamento farmacológico , Fraturas Ósseas/epidemiologia , Humanos , Estudos Prospectivos , Convulsões/tratamento farmacológico , Convulsões/epidemiologia
15.
Epilepsia ; 62(2): 358-370, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33475165

RESUMO

OBJECTIVE: To study the epilepsy syndromes among the severe epilepsies of infancy and assess their incidence, etiologies, and outcomes. METHODS: A population-based cohort study was undertaken of severe epilepsies with onset before age 18 months in Victoria, Australia. Two epileptologists reviewed clinical features, seizure videos, and electroencephalograms to diagnose International League Against Epilepsy epilepsy syndromes. Incidence, etiologies, and outcomes at age 2 years were determined. RESULTS: Seventy-three of 114 (64%) infants fulfilled diagnostic criteria for epilepsy syndromes at presentation, and 16 (14%) had "variants" of epilepsy syndromes in which there was one missing or different feature, or where all classical features had not yet emerged. West syndrome (WS) and "WS-like" epilepsy (infantile spasms without hypsarrhythmia or modified hypsarrhythmia) were the most common syndromes, with a combined incidence of 32.7/100 000 live births/year. The incidence of epilepsy of infancy with migrating focal seizures (EIMFS) was 4.5/100 000 and of early infantile epileptic encephalopathy (EIEE) was 3.6/100 000. Structural etiologies were common in "WS-like" epilepsy (100%), unifocal epilepsy (83%), and WS (39%), whereas single gene disorders predominated in EIMFS, EIEE, and Dravet syndrome. Eighteen (16%) infants died before age 2 years. Development was delayed or borderline in 85 of 96 (89%) survivors, being severe-profound in 40 of 96 (42%). All infants with EIEE or EIMFS had severe-profound delay or were deceased, but only 19 of 64 (30%) infants with WS, "WS-like," or "unifocal epilepsy" had severe-profound delay, and only two of 64 (3%) were deceased. SIGNIFICANCE: Three quarters of severe epilepsies of infancy could be assigned an epilepsy syndrome or "variant syndrome" at presentation. In this era of genomic testing and advanced brain imaging, diagnosing epilepsy syndromes at presentation remains clinically useful for guiding etiologic investigation, initial treatment, and prognostication.


Assuntos
Deficiências do Desenvolvimento/epidemiologia , Epilepsias Mioclônicas/epidemiologia , Espasmos Infantis/epidemiologia , Anticonvulsivantes/uso terapêutico , Pré-Escolar , Estudos de Coortes , Deficiências do Desenvolvimento/etiologia , Deficiências do Desenvolvimento/fisiopatologia , Progressão da Doença , Eletroencefalografia , Epilepsias Mioclônicas/tratamento farmacológico , Epilepsias Mioclônicas/etiologia , Epilepsias Mioclônicas/fisiopatologia , Síndromes Epilépticas/tratamento farmacológico , Síndromes Epilépticas/epidemiologia , Síndromes Epilépticas/etiologia , Síndromes Epilépticas/fisiopatologia , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Síndrome de Lennox-Gastaut/tratamento farmacológico , Síndrome de Lennox-Gastaut/epidemiologia , Síndrome de Lennox-Gastaut/etiologia , Síndrome de Lennox-Gastaut/fisiopatologia , Masculino , Malformações do Desenvolvimento Cortical/complicações , Malformações do Desenvolvimento Cortical/epidemiologia , Malformações do Desenvolvimento Cortical/cirurgia , Mortalidade , Índice de Gravidade de Doença , Espasmos Infantis/tratamento farmacológico , Espasmos Infantis/etiologia , Espasmos Infantis/fisiopatologia , Vitória/epidemiologia
16.
Br J Clin Pharmacol ; 87(2): 436-446, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32478863

RESUMO

AIMS: Severe behavioural problems (SBP) are a major contributor to morbidity in children with intellectual disability (ID). Medications used to treat SBP in ID are associated with a high risk of side effects. Cannabidiol has potential therapeutic effects in SBP. This pilot study aimed to investigate the feasibility of conducting a randomised placebo-controlled trial of cannabidiol to reduce SBP in children with ID. METHODS: This is a double-blind, placebo-controlled, two-armed, parallel-design, randomised controlled trial of cannabidiol in children aged 8-16 years with ID and SBP. Participants were randomised 1:1 to receive either 98% cannabidiol in oil (Tilray, Canada) or placebo orally for 8 weeks. The dose was up-titrated over 9 days to 20 mg/kg/day in two divided doses, with a maximum dose of 500 mg twice/day. The feasibility and acceptability of all study components were assessed. RESULTS: Eight children were randomised, and all completed the full study protocol. There were no serious adverse events or drop-outs. Protocol adherence for key study components was excellent: study visits 100%, medication adherence 100%, blood tests 92% and questionnaire completion 88%. Parents reported a high degree of acceptability with the study design. All parents reported they would recommend the study to other families with children with similar problems. There was an efficacy signal in favour of active drug. CONCLUSIONS: The findings suggest that the study protocol is feasible and acceptable to patients with ID and SBP and their families.


Assuntos
Canabidiol , Deficiência Intelectual , Comportamento Problema , Adolescente , Canadá , Criança , Método Duplo-Cego , Humanos , Deficiência Intelectual/tratamento farmacológico , Projetos Piloto
17.
Hum Mutat ; 41(1): 69-80, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31513310

RESUMO

Developmental and epileptic encephalopathies (DEE) refer to a heterogeneous group of devastating neurodevelopmental disorders. Variants in KCNB1 have been recently reported in patients with early-onset DEE. KCNB1 encodes the α subunit of the delayed rectifier voltage-dependent potassium channel Kv 2.1. We review the 37 previously reported patients carrying 29 distinct KCNB1 variants and significantly expand the mutational spectrum describing 18 novel variants from 27 unreported patients. Most variants occur de novo and mainly consist of missense variants located on the voltage sensor and the pore domain of Kv 2.1. We also report the first inherited variant (p.Arg583*). KCNB1-related encephalopathies encompass a wide spectrum of neurodevelopmental disorders with predominant language difficulties and behavioral impairment. Eighty-five percent of patients developed epilepsies with variable syndromes and prognosis. Truncating variants in the C-terminal domain are associated with a less-severe epileptic phenotype. Overall, this report provides an up-to-date review of the mutational and clinical spectrum of KCNB1, strengthening its place as a causal gene in DEEs and emphasizing the need for further functional studies to unravel the underlying mechanisms.


Assuntos
Epilepsia/diagnóstico , Epilepsia/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Variação Genética , Transtornos do Neurodesenvolvimento/diagnóstico , Transtornos do Neurodesenvolvimento/genética , Canais de Potássio Shab/genética , Alelos , Estudos de Associação Genética/métodos , Genótipo , Humanos , Fenótipo , Canais de Potássio Shab/química , Canais de Potássio Shab/metabolismo , Relação Estrutura-Atividade
18.
Epilepsia ; 61(11): 2461-2473, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32954514

RESUMO

OBJECTIVE: We aimed to delineate the phenotypic spectrum and long-term outcome of individuals with KCNB1 encephalopathy. METHODS: We collected genetic, clinical, electroencephalographic, and imaging data of individuals with KCNB1 pathogenic variants recruited through an international collaboration, with the support of the family association "KCNB1 France." Patients were classified as having developmental and epileptic encephalopathy (DEE) or developmental encephalopathy (DE). In addition, we reviewed published cases and provided the long-term outcome in patients older than 12 years from our series and from literature. RESULTS: Our series included 36 patients (21 males, median age = 10 years, range = 1.6 months-34 years). Twenty patients (56%) had DEE with infantile onset seizures (seizure onset = 10 months, range = 10 days-3.5 years), whereas 16 (33%) had DE with late onset epilepsy in 10 (seizure onset = 5 years, range = 18 months-25 years) and without epilepsy in six. Cognitive impairment was more severe in individuals with DEE compared to those with DE. Analysis of 73 individuals with KCNB1 pathogenic variants (36 from our series and 37 published individuals in nine reports) showed developmental delay in all with severe to profound intellectual disability in 67% (n = 41/61) and autistic features in 56% (n = 32/57). Long-term outcome in 22 individuals older than 12 years (14 in our series and eight published individuals) showed poor cognitive, psychiatric, and behavioral outcome. Epilepsy course was variable. Missense variants were associated with more frequent and more severe epilepsy compared to truncating variants. SIGNIFICANCE: Our study describes the phenotypic spectrum of KCNB1 encephalopathy, which varies from severe DEE to DE with or without epilepsy. Although cognitive impairment is worse in patients with DEE, long-term outcome is poor for most and missense variants are associated with more severe epilepsy outcome. Further understanding of disease mechanisms should facilitate the development of targeted therapies, much needed to improve the neurodevelopmental prognosis.


Assuntos
Encefalopatias/diagnóstico por imagem , Encefalopatias/genética , Epilepsia/diagnóstico por imagem , Epilepsia/genética , Variação Genética/genética , Canais de Potássio Shab/genética , Adolescente , Adulto , Encefalopatias/fisiopatologia , Criança , Pré-Escolar , Estudos de Coortes , Eletroencefalografia/tendências , Epilepsia/fisiopatologia , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
19.
Epilepsy Behav ; 106: 107005, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32199347

RESUMO

INTRODUCTION: Children with epilepsy report lower health-related quality of life (QOL) compared with healthy children and those with other chronic disorders. This study piloted the recently published Pediatric Quality of Life Inventory (PedsQL) Epilepsy Module (PedsQL-EM) in an ambulatory setting and studied epilepsy-related factors contributing to QOL in children with epilepsy. METHODS: Children with epilepsy aged 8-18 years who were ambulant and verbal were recruited from pediatric neurology clinics. Children and their caregivers completed age-appropriate versions of the PedsQL-EM (8-12 or 13-18 years) in the clinic waiting area. Treating neurologists completed medical questionnaires about their patients' epilepsy. RESULTS: We collected 151 parent-report and 127 self-report PedsQL-EMs. Administration time was 5-10 min with some children receiving assistance from the researcher. Mean age of children was 12.9+/-3.0, with 77 females (51%). Parents reported lower mean QOL scores across all subdomains compared with their children. Parents reported significantly lower QOL for children with earlier age at epilepsy onset, longer epilepsy duration, presence of seizures during the last month, more severe epilepsy, increased number of antiepileptic drugs (AEDs), and cognitive comorbidity. The same factors impacted on child self-reporting, but with more variability across subdomains. CONCLUSIONS: The PedsQL-EM is an epilepsy-specific measure of QOL that is quick and easy to administer and is sensitive to the clinical factors reported to impact on QOL in pediatric epilepsy.


Assuntos
Assistência Ambulatorial/normas , Epilepsia/psicologia , Pais/psicologia , Qualidade de Vida/psicologia , Autorrelato/normas , Inquéritos e Questionários/normas , Adolescente , Assistência Ambulatorial/métodos , Cuidadores/psicologia , Criança , Epilepsia/diagnóstico , Epilepsia/terapia , Feminino , Humanos , Masculino , Neurologistas/normas , Pediatras/normas
20.
J Paediatr Child Health ; 56(12): 1918-1923, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32965057

RESUMO

AIM: This paper describes the use of the single patient therapy plan (SPTP). The SPTP has been designed to assess the efficacy at an individual level of a commercially available cannabinoid product, cannabidiol, in reducing seizure frequency in paediatric patients with intractable epilepsy. METHODS: The SPTP is a randomised, double-blind, placebo-controlled N-of-1 trial designed to assess the efficacy of treatment in a neurology outpatient setting. The primary objective of the SPTP is to assess the efficacy of cannabidiol in reducing seizure frequency in each patient with intractable epilepsy, with change in seizure frequency being the primary outcome of interest. The analysis adopts a Bayesian approach, which provides results in the form of posterior probabilities that various levels of benefit (based on the primary outcome measure, seizure frequency) have been achieved under active treatment compared to placebo, accompanied by decision rules that provide thresholds for deciding whether treatment has been successful in the individual patient. The SPTP arrangement is most accurately considered part of clinical practice rather than research, since it is aimed at making clinical treatment decisions for individual patients and is not testing a hypothesis or collecting aggregate data. Therefore, Human Research Ethics Committee approval was considered not to be required, although it is recommended that hospital Clinical Ethics Committees provide ethical oversight. CONCLUSION: These SPTP resources are made available so that they may inform clinical practice in the treatment of severe epilepsy or adapted for use in other conditions.


Assuntos
Canabidiol , Epilepsia Resistente a Medicamentos , Anticonvulsivantes/uso terapêutico , Teorema de Bayes , Canabidiol/uso terapêutico , Criança , Método Duplo-Cego , Epilepsia Resistente a Medicamentos/tratamento farmacológico , Quimioterapia Combinada , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
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