Expedited epilepsy surgery prior to drug resistance in children: a frontier worth crossing?

Epilepsy surgery is an established safe and effective treatment for selected candidates with drug-resistant epilepsy. In this opinion piece, we outline the clinical and experimental evidence for selectively considering epilepsy surgery prior to drug resistance. Our rationale for expedited surgery is based on the observations that (i) a high proportion of patients with lesional epilepsies (e.g. focal cortical dysplasia, epilepsy-associated tumours) will progress to drug resistance; (ii) surgical treatment of these lesions, especially in non-eloquent areas of brain, is safe; and (iii) earlier surgery may be associated with better seizure outcomes. Potential benefits beyond seizure reduction or elimination include less exposure to antiseizure medications, which may lead to improved developmental trajectories in children and optimize long-term neurocognitive outcomes and quality of life. Further, there exists emerging experimental evidence that brain network dysfunction exists at the onset of epilepsy, where continuing dysfunctional activity could exacerbate network perturbations. This in turn could lead to expanded seizure foci and contribution to the comorbidities associated with epilepsy. Taken together, we rationalize that epilepsy surgery, in carefully selected cases, may be considered prior to drug resistance. Last, we outline the path forward, including the challenges associated with developing the evidence base and implementing this paradigm into clinical care.

Differential regulation of gene expression pathways with dexamethasone and ACTH after early life seizures.

Early-life seizures (ELS) are associated with persistent cognitive deficits such as ADHD and memory impairment. These co-morbidities have a dramatic negative impact on the quality of life of patients. Therapies that improve cognitive outcomes have enormous potential to improve patients' quality of life. Our previous work in a rat flurothyl-induction model showed that administration of adrenocorticotropic hormone (ACTH) at time of seizure induction led to improved learning and memory in the animals despite no effect on seizure latency or duration. Administration of dexamethasone (Dex), a corticosteroid, did not have the same positive effect on learning and memory and has even been shown to exacerbate injury in a rat model of temporal lobe epilepsy. We hypothesized that ACTH exerted positive effects on cognitive outcomes through beneficial changes to gene expression and proposed that administration of ACTH at seizure induction would return gene-expression in the brain towards the normal pattern of expression in the Control animals whereas Dex would not. Twenty-six Sprague-Dawley rats were randomized into vehicle- Control, and ACTH-, Dex-, and vehicle- ELS. Rat pups were subjected to 60 flurothyl seizures from P5 to P14. After seizure induction, brains were removed and the hippocampus and PFC were dissected, RNA was extracted and sequenced, and differential expression analysis was performed using generalized estimating equations. Differential expression analysis showed that ACTH pushes gene expression in the brain back to a more normal state of expression through enrichment of pathways involved in supporting homeostatic balance and down-regulating pathways that might contribute to excitotoxic cell-damage post-ELS.

Seizure outcome determinants in children after surgery for single unilateral lesions on magnetic resonance imaging: Role of preoperative ictal and interictal electroencephalography.

OBJECTIVE: To determine whether an ictal electroencephalographic (EEG) recording as part of presurgical evaluation of children with a demarcated single unilateral magnetic resonance imaging (MRI) lesion is indispensable for surgical decision-making, we investigated the relationship of interictal/ictal EEG and seizure semiology with seizure-free outcome. METHODS: Data were obtained retrospectively from consecutive patients (≤18 years old) undergoing epilepsy surgery with a single unilateral MRI lesion at our institution over a 6-year period. Video-telemetry EEG (VT-EEG) was classified as concordant or nonconcordant/noninformative in relation to the MRI lesion location. The odds of seizure-free outcome associated with nonconcordant versus concordant for semiology, interictal EEG, and ictal EEG were compared separately. Multivariate logistic regression was conducted to correct for confounding variables. RESULTS: After a median follow-up of 26 months (interquartile range = 17-37.5), 73 (69%) of 117 children enrolled were seizure-free. Histopathological diagnoses included low-grade epilepsy-associated tumors, n = 46 (39%); focal cortical dysplasia (FCD), n = 33 (28%); mesial temporal sclerosis (MTS), n = 23 (20%); polymicrogyria, n = 3 (3%); and nondiagnostic findings/gliosis, n = 12 (10%). The odds of seizure freedom were lower with a nonconcordant interictal EEG (odds ratio [OR] = .227, 95% confidence interval [CI] = .079-.646, p = .006) and nonconcordant ictal EEG (OR = .359, 95% CI = .15-.878, p = .035). In the multivariate logistic regression model, factors predicting lower odds for seizure-free outcome were developmental delay/intellectual disability and higher number of antiseizure medications tried, with a nonsignificant trend for "nonconcordant interictal EEG." In the combined subgroup of patients with FCD and tumors (n = 79), there was no significant relationship of VT-EEG factors and seizure outcomes, whereas in children with MTS and acquired lesions (n = 25), a nonconcordant EEG was associated with poorer seizure outcomes (p = .003). SIGNIFICANCE: An ictal EEG may not be mandatory for presurgical evaluation, particularly when a well-defined single unilateral MRI lesion has been identified and the interictal EEG is concordant.

Fine Spike Timing in Hippocampal-Prefrontal Ensembles Predicts Poor Encoding and Underlies Behavioral Performance in Healthy and Malformed Brains.

Spatial working memory (SWM) is a central cognitive process during which the hippocampus and prefrontal cortex (PFC) encode and maintain spatial information for subsequent decision-making. This occurs in the context of ongoing computations relating to spatial position, recall of long-term memory, attention, among many others. To establish how intermittently presented information is integrated with ongoing computations we recorded single units, simultaneously in hippocampus and PFC, in control rats and those with a brain malformation during performance of an SWM task. Neurons that encode intermittent task parameters are also well modulated in time and incorporated into a functional network across regions. Neurons from animals with cortical malformation are poorly modulated in time, less likely to encode task parameters, and less likely to be integrated into a functional network. Our results implicate a model in which ongoing oscillatory coordination among neurons in the hippocampal-PFC network describes a functional network that is poised to receive sensory inputs that are then integrated and multiplexed as working memory. The background temporal modulation is systematically altered in disease, but the relationship between these dynamics and behaviorally relevant firing is maintained, thereby providing potential targets for stimulation-based therapies.

Focal Dorsal Hippocampal Nav1.1 Knock Down Alters Place Cell Temporal Coordination and Spatial Behavior.

Alterations in the voltage-gated sodium channel Nav.1.1 are implicated in various neurological disorders, including epilepsy, Alzheimer's disease, and autism spectrum disorders. Previous studies suggest that the reduction of Nav1.1 expression leads to a decrease of fast spiking activity in inhibitory neurons. Because interneurons (INs) play a critical role in the temporal organization of neuronal discharge, we hypothesize that Nav1.1 dysfunction will negatively impact neuronal coordination in vivo. Using shRNA interference, we induced a focal Nav1.1 knock-down (KD) in the dorsal region of the right hippocampus of adult rats. Focal, unilateral Nav1.1 KD decreases the performance in a spatial novelty recognition task and the firing rate in INs, but not in pyramidal cells. It reduced theta/gamma coupling of hippocampal oscillations and induced a shift in pyramidal cell theta phase preference. Nav1.1 KD degraded spatial accuracy and temporal coding properties of place cells, such as theta phase precession and compression of ongoing sequences. Aken together, these data demonstrate that a deficit in Nav1.1 alters the temporal coordination of neuronal firing in CA1 and impairs behaviors that rely on the integrity of this network. They highlight the potential contribution of local inhibition in neuronal coordination and its impact on behavior in pathological conditions.

Subcortical nuclei volumes are associated with cognition in children post-convulsive status epilepticus: Results at nine years follow-up.

PURPOSE: The purpose of the present study was to investigate the relationship between subcortical nuclei volume and cognition in children with post-convulsive status epilepticus (CSE). METHODS: Structural T1-weighted magnetic resonance imaging (MRI) scans (Siemens Avanto, 1.5 T) and neuropsychological assessments (full-scale intelligence quotient (FSIQ) and Global Memory Scores (GMS)) were collected from subjects at a mean 8.5 years post-CSE (prolonged febrile seizures (PFS), n = 30; symptomatic/known, n = 28; and other, n = 12) and from age- and sex-matched healthy controls (HC). Subjects with CSE were stratified into those with lower cognitive ability (LCA) (CSE+, n = 22) and those without (CSE-, n = 48). Quantitative volumetric analysis using Functional MRI of the Brain Software Library (FSL) (Analysis Group, FMRIB, Oxford) provided segmented MRI brain volumes. Univariate analysis of covariance (ANCOVA) was performed to compare subcortical nuclei volumes across subgroups. Multivariable linear regression was performed for each subcortical structure and for total subcortical volume (SCV) to identify significant predictors of LCA (FSIQ <85) while adjusting for etiology, age, socioeconomic status, sex, CSE duration, and intracranial volume (ICV); Bonferroni correction was applied for the analysis of individual subcortical nuclei. RESULTS: Seventy subjects (11.8 ±â€¯3.4 standard deviation (SD) years; 34 males) and 72 controls (12.1 ±â€¯3.0SD years; 29 males) underwent analysis. Significantly smaller volumes of the left thalamus, left caudate, right caudate, and SCV were found in subjects with CSE+ compared with HC, after adjustment for intracranial, gray matter (GM), or cortical/cerebellar volume. When compared with subjects with CSE-, subjects with CSE+ also had smaller volumes of the left thalamus, left pallidum, right pallidum, and SCV. Individual subcortical nuclei were not associated, but SCV was associated with FSIQ (p = 0.005) and GMS (p = 0.014). Intracranial volume and etiology were similarly predictive. CONCLUSIONS: Nine years post-CSE, SCV is significantly lower in children who have LCA compared with those that do not. However, in this cohort, we are unable to determine whether the relationship is independent of ICV or etiology. Future, larger scale studies may help tease this out.

Current understanding of febrile seizures and their long-term outcomes.

In this paper we reframe febrile seizures, which are viewed as a symptom of an underlying brain disorder. The general observation is that a small cohort of children will develop febrile seizures (2-5% in the West), while the greater majority will not. This suggests that the brain that generates a seizure, in an often-mild febrile context, differs in some ways from the brain that does not. While the underlying brain disorder appears to have no significant adverse implication in the majority of children with febrile seizures, serious long-term outcomes (cognitive and neuropsychiatric) have been recently reported, including sudden death. These adverse events likely reflect the underlying intrinsic brain pathology, as yet undefined, of which febrile seizures are purely a manifestation and not the primary cause. A complex interaction between brain-genetics-epigenetics-early environment is likely at play. In view of this emerging data, it is time to review whether febrile seizures are a single entity, with a new and multidimensional approach needed to help with predicting outcome. WHAT THIS PAPER ADDS: A febrile seizure is due to a brain's aberrant response to high temperature. Problems in a small group of children are now being identified later in life. There is no clear correlation between duration or other characteristics of febrile seizures and subsequent mesial temporal sclerosis.

Protein S-acyl transferase 15 is involved in seed triacylglycerol catabolism during early seedling growth in Arabidopsis.

Seeds of Arabidopsis contain ~40% oil, which is primarily in the form of triacylglycerol and it is converted to sugar to support post-germination growth. We identified an Arabidopsis T-DNA knockout mutant that is sugar-dependent during early seedling establishment and determined that the ß-oxidation process involved in catabolising the free fatty acids released from the seed triacylglycerol is impaired. The mutant was confirmed to be transcriptional null for Protein Acyl Transferase 15, AtPAT15 (At5g04270), one of the 24 protein acyl transferases in Arabidopsis. Although it is the shortest, AtPAT15 contains the signature 'Asp-His-His-Cys cysteine-rich domain' that is essential for the enzyme activity of this family of proteins. The function of AtPAT15 was validated by the fact that it rescued the growth defect of the yeast protein acyl transferase mutant akr1 and it was also auto-acylated in vitro. Transient expression in Arabidopsis and tobacco localised AtPAT15 in the Golgi apparatus. Taken together, our data demonstrate that AtPAT15 is involved in ß-oxidation of triacylglycerol, revealing the importance of protein S-acylation in the breakdown of seed-storage lipids during early seedling growth of Arabidopsis.

Long-term outcomes after childhood convulsive status epilepticus.

PURPOSE OF REVIEW: It is widely accepted that childhood convulsive status epilepticus (CSE) has associated short-term and long-term mortality and morbidity. However, the role of CSE itself on subsequent adverse outcomes is still debated. In addition, whether prolonged seizures cause any long-term hippocampal injury and developmental or memory impairment is uncertain. In this review, we aim to provide an overview of long-term outcomes after childhood CSE, highlighting data from recent literature on this subject. RECENT FINDINGS: Long-term outcome after childhood CSE is favorable in previously normal children, with low incidence of epilepsy, motor and intellectual disability, behavioral impairment and need for special educational provision. Mesial temporal sclerosis is uncommon in children after prolonged febrile seizures. There is substantial morbidity after childhood CSE, but this is seen primarily in children with symptomatic causes and preexisting neurological abnormalities. Cause is the primary determinant of outcomes after childhood CSE and the additional effect of CSE characteristics such as seizure duration seems to be less than previously believed. SUMMARY: Childhood CSE is associated with substantial neurological, cognitive and behavioral morbidity. Early identification of these difficulties and appropriate intervention are likely to have a major positive impact on their quality of life.

Experiences and needs of parents of young children with active epilepsy: A population-based study.

The aim of the study was to gain a comprehensive understanding of the experiences and needs of parents of young children with epilepsy from a total population sample. The parents (mothers (n = 38), fathers (n = 9)) of 40/53 (75% of total population) young children (1-7 years; 23 males, 17 females) with 'active' epilepsy (had a seizure in the last year or taking Anti-epileptic drugs (AEDs)) were interviewed either in person or over the telephone using a semistructured interview schedule. The families were resident in the south of the UK. The interviews were audio-recorded, transcribed, and coded using thematic analysis. Thematic analysis revealed six main themes: diagnostic journey, parental perception of epilepsy management, awareness and impact of associated neurobehavioral difficulties, inconsistent availability of therapeutic and educational supports, impact on family functioning, and need for parental support. Parents reported often having difficulty accessing a professional knowledgeable about epilepsy. While parents were generally satisfied with the initial information they received about seizures and their management, they reported that the association between epilepsy and neurobehavioral issues was often not broached. These developmental/behavioral difficulties often had a bigger impact on child wellbeing and family functioning, but provision of therapeutic and educational supports for the difficulties was often very patchy. Parents noted that early onset epilepsy and associated neurobehavioral difficulties often have a very significant impact on family functioning including increased restrictions on family activities and increased financial burden. Parents would like informational and emotional support to extend beyond the time of epilepsy diagnosis. There is a clear need for comprehensive childhood epilepsy services to include provision for identification and management of child neurobehavioral needs and a focus on family-centered care.

Intelligence and memory outcomes within 10 years of childhood convulsive status epilepticus.

Long-term intelligence and memory outcomes of children post convulsive status epilepticus (CSE) have not been systematically investigated despite evidence of short-term impairments in CSE. The present study aimed to describe intelligence and memory outcomes in children within 10 years of CSE and identify potential risk factors for adverse outcomes. In this cohort study, children originally identified by the population-based North London Convulsive Status Epilepticus in Childhood Surveillance Study (NLSTEPSS) were prospectively recruited between July 2009 and February 2013 and invited for neuropsychological assessments and magnetic resonance imaging (MRI) scans. Full-scale intelligence quotients (FSIQs) were measured using the Wechsler Abbreviated Scales of Intelligence (WASI), and global memory scores (GMS) was assessed using the Children's Memory Scale (CMS). The cohort was analyzed as a whole and stratified into a prolonged febrile seizures (PFS) and non-PFS group. Their performance was compared with population norms and controls. Regression models were fitted to identify predictors of outcomes. With a mean of 8.9 years post-CSE, 28.5% of eligible participants were unable to undertake testing because of their severe neurodevelopmental deficits. Children with CSE who undertook formal testing (N = 94) were shown to have significantly lower FSIQ (p = 0.001) and GMS (p = 0.025) from controls; the PFS group (N = 34) had lower FSIQs (p = 0.022) but similar memory quotients (p = 0.88) with controls. Intracranial volume (ICV), developmental delay at baseline, and active epilepsy at follow-up were predictive of long-term outcomes in the non-PFS group. The relationship between ICV and outcomes was absent in the PFS group despite its presence in the control and non-PFS groups. Post-CSE, survivors reveal significant intelligence and memory impairments, but prognosis differs by CSE type; memory scores are uncompromised in the PFS group despite evidence of their lower FSIQ whereas both are compromised in the non-PFS group. Correlations between brain volumes and outcomes differ in the PFS, non-PFS, and control groups and require further investigation.

Global development and adaptive behaviour in children with early-onset epilepsy: a population-based case-control study.

AIM: There are limited population-based data on global development and adaptive behaviour in children with early-onset epilepsy. The aims of this study were: (1) to identify the prevalence of deficits in global development and adaptive behaviour experienced by children with early-onset epilepsy; (2) to identify factors associated with such deficits; and (3) to compare the relationship between measures of neurodevelopment in the group with epilepsy to a group without epilepsy who had other neurological or neurodevelopmental difficulties. METHOD: The Sussex Early Epilepsy and Neurobehaviour study is a prospective, community-based study involving children (1-7y) with epilepsy. We undertook comprehensive psychological assessment with participants, including measures of global development and adaptive behaviour. We compared the children with epilepsy with a sex, age, and developmentally-matched group of children without epilepsy who had neurodevelopmental or neurological difficulties using correlation matrices. RESULTS: Forty-eight children (91% of the eligible population) with epilepsy underwent assessment. Seventy-one per cent of children displayed delayed global development (<2SD) and 56% showed significant deficits (<2SD) in adaptive behaviour. Our analysis revealed that non-white ethnicity and use of polytherapy were independently associated with decreased scores on measures of global development and adaptive behaviour. The correlations between measures of developmental functioning were higher in children with epilepsy than in those without. INTERPRETATION: Children with early-onset epilepsy frequently have difficulties with global development and adaptive behaviour. The higher correlations between neurodevelopmental measures in children with epilepsy suggest that the profile in children with epilepsy is different. This may have significant implications for both neuropathology and interventions. WHAT THIS PAPER ADDS: Children with early-onset epilepsy are at significant risk of intellectual disability. Developmental impairment is associated with use of polytherapy but not with any seizure parameters. Developmental profiles in young children with epilepsy differ from other conditions.

WONOEP APPRAISAL: The many facets of epilepsy networks.

The brain is a complex system composed of networks of interacting elements, from genes to circuits, whose function (and dysfunction) is not derivable from the superposition of individual components. Epilepsy is frequently described as a network disease, but to date, there is no standardized framework within which network concepts applicable to all levels from genes to whole brain can be used to generate deeper insights into the pathogenesis of seizures or the associated morbidities. To address this shortcoming, the Neurobiology Commission of the International League Against Epilepsy dedicated a Workshop on Neurobiology of Epilepsy (XIV WONOEP 2017) with the aim of formalizing network concepts as they apply to epilepsy and to critically discuss whether and how such concepts could augment current research endeavors. Here, we review concepts and strategies derived by considering epilepsy as a disease of different network hierarchies that range from genes to clinical phenotypes. We propose that the concept of networks is important for understanding epilepsy and is critical for developing new study designs. These approaches could ultimately facilitate the development of novel diagnostic and therapeutic strategies.

Cognitive outcomes following epilepsy in infancy: A longitudinal community-based study.

OBJECTIVE: Onset of epilepsy before 2 years of age is associated with poor cognitive outcome; however, the natural course of the range of epilepsies that occur at this age is unknown. The aim of this prospective community-based study was to investigate the neuropsychological development of infants with newly diagnosed epilepsy longitudinally and to identify the clinical factors that predict long-term impairment. METHODS: Sixty-six infants <24 months of age were enrolled in the baseline phase of this study; 40 were seen again at 1-year follow-up and 40 at 3-year follow-up. Children underwent a neurological and neuropsychological assessment at each time point. RESULTS: More than 55% of children demonstrated impaired cognitive functioning at each assessment, with a similar percentage showing impaired memory and attention at 3-year follow-up. Cognitive scores obtained at each time point were correlated. More than 20 seizures/seizure clusters prior to assessment and an abnormal neurologic examination predicted poor cognitive functioning at baseline, whereas continuing seizures and baseline cognitive score predicted 3-year intelligence quotient (IQ)/cognitive score. SIGNIFICANCE: These findings demonstrate the following: (1) infants who are performing poorly at baseline continue to display impaired development at follow-up, (2) these children are delayed across a range of neuropsychological functions, and (3) a high number of seizures close to initial diagnosis and continuing seizures at follow-up independently predict cognitive impairment. These findings help to identify those infants with new-onset epilepsy who are most at risk for poor developmental outcome and suggest that multimodal interventions should be instituted early in the course of the disorder to improve outcomes.

Parenting stress and perceived stigma in mothers of young children with epilepsy: A case-control study.

The aim was to provide data on parenting stress and perceived stigma in mothers (n = 47) of young children with epilepsy, and to compare findings with those of mothers (n = 48) of developmental, age- and gender-matched children with nonepilepsy-related neurodisability (neurological and/or neurodevelopmental concerns). The mothers of young children (1-7 years) with epilepsy and mothers of children with neurodisability in a defined geographical area of the UK, completed the Parenting Stress Index-4th Edition (PSI-4) and a measure of perceived stigma. Factors associated with parenting stress and stigma were analyzed using linear regression. Thirty-eight percent of mothers of children with epilepsy scored in the at-risk range (>85th percentile) on the Total Stress score of the PSI-4 (Neurodisability 21%) (p = 0.06). Significantly more mothers of children with epilepsy scored in the at-risk range on the Parent-Child Dysfunctional Interaction subscale than mothers of children with neurodisability (Epilepsy 45% vs. Neurodisability 21%; p = 0.01), but not on the Parental Distress subscale (Epilepsy 32% vs. Neurodisability 23%; p = 0.33) or Difficult Child (Epilepsy 57% vs. Neurodisability 46%; p = 0.26) subscales. There was no statistically significant difference in perceived stigma between mothers in both groups (p = 0.51). Factors significantly associated with increased parenting stress in the group with epilepsy were child behavior difficulties (p < 0.001) and maternal sleep difficulties (p = 0.02). Lower child developmental level was the only factor independently associated with increased stigma in the group with epilepsy (p = 0.08). Mothers of young children with epilepsy report high levels of parenting stress and higher levels of difficulties with parent-child interaction compared with that of mothers of children with nonepilepsy-related neurodisability. Parenting stress and stigma in epilepsy were not associated with epilepsy factors. Efforts at reducing parenting stress and stigma should focus on interventions targeting child development and maternal sleep.

Symptoms of depression, anxiety, and stress in parents of young children with epilepsy: A case controlled population-based study.

The objective was to provide population-based data on depression, anxiety, and stress in parents of young children with epilepsy and to compare findings with those of parents of developmental-, age-, and gender-matched children with nonepilepsy-related neurodisability (neurological and/or neurodevelopmental concerns). The parents (mothers and fathers) of 47 (89% ascertainment) young children (1-7years) with epilepsy in a defined geographical area of the UK completed the Depression Anxiety Stress Scales - Short Form (DASS-21), a screening measure for depression, anxiety, and stress. The responses of parents of children with epilepsy were compared with parents of developmental-, age-, and gender-matched children with nonepilepsy-related neurodisability (n=48). Factors associated with parental symptoms were analyzed using regression. In the group with epilepsy, 47 mothers and 39 fathers completed the DASS-21. Seventy-two percent of mothers scored in the at-risk range on at least one DASS-21 subscale (Fathers 49%). Mothers of children with epilepsy were significantly more likely to score in the at risk range than fathers on depression (55% vs. 33%), anxiety (47% vs. 26%), and stress (55% vs. 31%) subscales (all p<0.05). Mothers of children with epilepsy were also significantly more likely to score in the at-risk range than mothers of children with neurodisability on measures of depression (p=0.005) and stress (p=0.03). There was not a significant difference between fathers in both groups on any measures. In the group with epilepsy, increased child emotional-behavioral difficulties were associated with increased DASS-21 scores on multivariable analysis (p=0.04). Mothers of young children with epilepsy are at high risk for mental health difficulties, and all should be screened for such difficulties. There is a need to explore what parent and/or child focused interventions might be useful to reduce the mental health difficulties reported by mothers of young children with epilepsy.

Long-term behavioural outcomes after paediatric convulsive status epilepticus: a population-based cohort study.

AIM: To describe behavioural and psychiatric outcomes of children within 10 years of convulsive status epilepticus (CSE). METHOD: Children originally identified by the population-based North London Convulsive Status Epilepticus in Childhood Surveillance Study were followed-up between July 2009 and February 2013. They were grouped into epilepsy- and non-epilepsy-related CSE, and compared with population norms and healthy controls using the Strengths and Difficulties Questionnaire; the Autism Spectrum Screening Questionnaire; and the Swanson, Nolan, and Pelham questionnaire. Children who scored above recommended clinical cut-offs on any scale were invited for a neuropsychiatric assessment. Regression models were fitted to identify clinically relevant covariates associated with behavioural outcomes. RESULTS: At a mean follow-up of 8.1 years post-CSE, 28% of enrolled children were found to have a psychiatric disorder. Children with epilepsy-related CSE scored higher than norms on all scales and children with non-epilepsy-related CSE scored higher than norms on the Strengths and Difficulties Questionnaire and the Autism Spectrum Screening Questionnaire. Presence of seizures at baseline and recurrence of CSE was associated with worse outcomes in the group with epilepsy. Intellectual abilities were associated with behavioural outcomes in all participants. INTERPRETATION: A large proportion of children manifest behavioural issues 8 years after CSE. The present data highlight the need for behavioural screening in children with neurodevelopmental impairments post-CSE. WHAT THIS PAPER ADDS: Eight years post convulsive status epilepticus (CSE), 37% of parents report behavioural issues. Of enrolled children, 28% were found to have a Diagnostic and Statistical Manual mental disorder. Intellectual abilities are strongly associated with behavioural outcomes in children post-CSE.

PCP-B class pollen coat proteins are key regulators of the hydration checkpoint in Arabidopsis thaliana pollen-stigma interactions.

The establishment of pollen-pistil compatibility is strictly regulated by factors derived from both male and female reproductive structures. Highly diverse small cysteine-rich proteins (CRPs) have been found to play multiple roles in plant reproduction, including the earliest stages of the pollen-stigma interaction. Secreted CRPs found in the pollen coat of members of the Brassicaceae, the pollen coat proteins (PCPs), are emerging as important signalling molecules that regulate the pollen-stigma interaction. Using a combination of protein characterization, expression and phylogenetic analyses we identified a novel class of Arabidopsis thaliana pollen-borne CRPs, the PCP-Bs (for pollen coat protein B-class) that are related to embryo surrounding factor (ESF1) developmental regulators. Single and multiple PCP-B mutant lines were utilized in bioassays to assess effects on pollen hydration, adhesion and pollen tube growth. Our results revealed that pollen hydration is severely impaired when multiple PCP-Bs are lost from the pollen coat. The hydration defect also resulted in reduced pollen adhesion and delayed pollen tube growth in all mutants studied. These results demonstrate that AtPCP-Bs are key regulators of the hydration 'checkpoint' in establishment of pollen-stigma compatibility. In addition, we propose that interspecies diversity of PCP-Bs may contribute to reproductive barriers in the Brassicaceae.

Protein S-Acyltransferase 14: A Specific Role for Palmitoylation in Leaf Senescence in Arabidopsis.

The Asp-His-His-Cys-Cys-rich domain-containing Protein S-Acyl Transferases (PATs) are multipass transmembrane proteins that catalyze S-acylation (commonly known as S-palmitoylation), the reversible posttranslational lipid modification of proteins. Palmitoylation enhances the hydrophobicity of proteins, contributes to their membrane association, and plays roles in protein trafficking and signaling. In Arabidopsis (Arabidopsis thaliana), there are at least 24 PATs; previous studies on two PATs established important roles in growth, development, and stress responses. In this study, we identified a, to our knowledge, novel PAT, AtPAT14, in Arabidopsis. Complementation studies in yeast (Saccharomyces cerevisiae) and Arabidopsis demonstrate that AtPAT14 possesses PAT enzyme activity. Disruption of AtPAT14 by T-DNA insertion resulted in an accelerated senescence phenotype. This coincided with increased transcript levels of some senescence-specific and pathogen-resistant marker genes. We show that early senescence of pat14 does not involve the signaling molecules jasmonic acid and abscisic acid, or autophagy, but associates with salicylic acid homeostasis and signaling. This strongly suggests that AtPAT14 plays a pivotal role in regulating senescence via salicylic acid pathways. Senescence is a complex process required for normal plant growth and development and requires the coordination of many genes and signaling pathways. However, precocious senescence results in loss of biomass and seed production. The negative regulation of leaf senescence by AtPAT14 in Arabidopsis highlights, to our knowledge for the first time, a specific role for palmitoylation in leaf senescence.

Hypomethylated pollen bypasses the interploidy hybridization barrier in Arabidopsis.

Plants of different ploidy levels are separated by a strong postzygotic hybridization barrier that is established in the endosperm. Deregulated parent-of-origin specific genes cause the response to interploidy hybridizations, revealing an epigenetic basis of this phenomenon. In this study, we present evidence that paternal hypomethylation can bypass the interploidy hybridization barrier by alleviating the requirement for the Polycomb Repressive Complex 2 (PRC2) in the endosperm. PRC2 epigenetically regulates gene expression by applying methylation marks on histone H3. Bypass of the barrier is mediated by suppressed expression of imprinted genes. We show that the hypomethylated pollen genome causes de novo CHG methylation directed to FIS-PRC2 target genes, suggesting that different epigenetic modifications can functionally substitute for each other. Our work presents a method for the generation of viable triploids, providing an impressive example of the potential of epigenome manipulations for plant breeding.