Phosphorylation of the axial element protein Hop1 by Mec1/Tel1 ensures meiotic interhomolog recombination.

An essential feature of meiosis is interhomolog recombination whereby a significant fraction of the programmed meiotic double-strand breaks (DSBs) is repaired using an intact homologous non-sister chromatid rather than a sister. Involvement of Mec1 and Tel1, the budding yeast homologs of the mammalian ATR and ATM kinases, in meiotic interhomlog bias has been implicated, but the mechanism remains elusive. Here, we demonstrate that Mec1 and Tel1 promote meiotic interhomolog recombination by targeting the axial element protein Hop1. Without Mec1/Tel1 phosphorylation of Hop1, meiotic DSBs are rapidly repaired via a Dmc1-independent intersister repair pathway, resulting in diminished interhomolog crossing-over leading to spore lethality. We find that Mec1/Tel1-mediated phosphorylation of Hop1 is required for activation of Mek1, a meiotic paralogue of the DNA-damage effector kinase, Rad53p/CHK2. Thus, Hop1 is a meiosis-specific adaptor protein of the Mec1/Tel1 signaling pathway that ensures interhomolog recombination by preventing Dmc1-independent repair of meiotic DSBs.

The underlying etiology of infantile spasms (West syndrome): Information from the International Collaborative Infantile Spasms Study (ICISS).

OBJECTIVE: To determine the underlying etiologies in a contemporary cohort of infants with infantile spasms and to examine response to treatment. METHODS: Identification of the underlying etiology and response to treatment in 377 infants enrolled in a clinical trial of the treatment of infantile spasms between 2007 and 2014 using a systematic review of history, examination, and investigations. They were classified using the pediatric adaptation of International Classification of Diseases, Tenth Revision (ICD-10). RESULTS: A total of 219 of 377 (58%) had a proven etiology, of whom 128 (58%) responded, 58 of 108 (54%) were allocated hormonal treatment, and 70 of 111 (63%) had combination therapy. Fourteen of 17 (82%, 95% confidence interval [CI] 59% to 94%) infants with stroke and infarct responded (compared to 114 of 202 for the rest of the proven etiology group (56%, 95% CI 48% to 62%, chi-square 4.3, P = .037): the better response remains when treatment allocation and lead time are taken into account (odds ratio 5.1, 95% CI 1.1 to 23.6, P = .037). Twenty of 37 (54%, 95% CI 38% to 70%) infants with Down syndrome had cessation of spasms compared to 108 of 182 (59%, 95% CI 52% to 66%, chi-square 0.35, P = .55) for the rest of the proven etiology group. The lack of a significant difference remains after taking treatment modality and lead-time into account (odds ratio 0.8, 95% CI 0.4 to 1.7, P = .62). In Down syndrome infants, treatment modality did not appear to affect response: 11 of 20 (55%) allocated hormonal therapy responded, compared to 9 of 17 (53%) allocated combination therapy. SIGNIFICANCE: This classification allows easy comparison with other classifications and with our earlier reports. Stroke and infarct have a better outcome than other etiologies, whereas Down syndrome might not respond to the addition of vigabatrin to hormonal treatment.

Outcome of seizures in the general population after 25†years: a prospective follow-up, observational cohort study.

OBJECTIVES: We investigated long-term (to 25 years) seizure prognosis and survival in people with newly diagnosed epilepsy in the community. We explored whether prognosis is different in those with epilepsy (>2 unprovoked seizures) and those with a single seizure at presentation. METHODS: This is a prospective observational cohort study of people with newly diagnosed seizures. We investigated seizure outcome and survival in people presenting with a single seizure and in those presenting with >2 seizures (epilepsy). RESULTS: 695 people (median follow-up 23.6 years) had unprovoked epileptic seizures. For seizure analysis we excluded 38 people with missing data leaving 657 (309 male, and 249 aged <18 years). Seizures recurred in 67%. The 354 people with epilepsy were only slightly more likely to have further seizure recurrence than the 302 people with a single seizure at presentation (HR 1.32, 95% CI 1.09 to 1.59). In 327 people with complete follow-up, 268 (82%, 95% CI 77% to 86%) were in terminal remission; (80%, (95% CI 73% to 85%) in those with epilepsy at presentation). Premature mortality was increased in people with epilepsy (standardised mortality ratio 1.67; 95% CI 1.40 to 1.99) and those with a single seizure at presentation (standardised mortality ratio 2.65; 95% CI 2.23 to 3.15). It is also high in those with early remission. CONCLUSIONS: People with epilepsy and with single seizures at presentation in the community generally have good prognosis for seizure control with prolonged follow-up. The risk of premature mortality is significantly increased in both groups.

Recombinogenic conditions influence partner choice in spontaneous mitotic recombination.

Mammalian common fragile sites are loci of frequent chromosome breakage and putative recombination hotspots. Here, we utilized Replication Slow Zones (RSZs), a budding yeast homolog of the mammalian common fragile sites, to examine recombination activities at these loci. We found that rates of URA3 inactivation of a hisG-URA3-hisG reporter at RSZ and non-RSZ loci were comparable under all conditions tested, including those that specifically promote chromosome breakage at RSZs (hydroxyurea [HU], mec1Δ sml1Δ, and high temperature), and those that suppress it (sml1Δ and rrm3Δ). These observations indicate that RSZs are not recombination hotspots and that chromosome fragility and recombination activity can be uncoupled. Results confirmed recombinogenic effects of HU, mec1Δ sml1Δ, and rrm3Δ and identified temperature as a regulator of mitotic recombination. We also found that these conditions altered the nature of recombination outcomes, leading to a significant increase in the frequency of URA3 inactivation via loss of heterozygosity (LOH), the type of genetic alteration involved in cancer development. Further analyses revealed that the increase was likely due to down regulation of intrachromatid and intersister (IC/IS) bias in mitotic recombination, and that RSZs exhibited greater sensitivity to HU dependent loss of IC/IS bias than non RSZ loci. These observations suggest that recombinogenic conditions contribute to genome rearrangements not only by increasing the overall recombination activity, but also by altering the nature of recombination outcomes by their effects on recombination partner choice. Similarly, fragile sites may contribute to cancer more frequently than non-fragile loci due their enhanced sensitivity to certain conditions that down-regulate the IC/IS bias rather than intrinsically higher rates of recombination.

Budding yeast ATM/ATR control meiotic double-strand break (DSB) levels by down-regulating Rec114, an essential component of the DSB-machinery.

An essential feature of meiosis is Spo11 catalysis of programmed DNA double strand breaks (DSBs). Evidence suggests that the number of DSBs generated per meiosis is genetically determined and that this ability to maintain a pre-determined DSB level, or "DSB homeostasis", might be a property of the meiotic program. Here, we present direct evidence that Rec114, an evolutionarily conserved essential component of the meiotic DSB-machinery, interacts with DSB hotspot DNA, and that Tel1 and Mec1, the budding yeast ATM and ATR, respectively, down-regulate Rec114 upon meiotic DSB formation through phosphorylation. Mimicking constitutive phosphorylation reduces the interaction between Rec114 and DSB hotspot DNA, resulting in a reduction and/or delay in DSB formation. Conversely, a non-phosphorylatable rec114 allele confers a genome-wide increase in both DSB levels and in the interaction between Rec114 and the DSB hotspot DNA. These observations strongly suggest that Tel1 and/or Mec1 phosphorylation of Rec114 following Spo11 catalysis down-regulates DSB formation by limiting the interaction between Rec114 and DSB hotspots. We also present evidence that Ndt80, a meiosis specific transcription factor, contributes to Rec114 degradation, consistent with its requirement for complete cessation of DSB formation. Loss of Rec114 foci from chromatin is associated with homolog synapsis but independent of Ndt80 or Tel1/Mec1 phosphorylation. Taken together, we present evidence for three independent ways of regulating Rec114 activity, which likely contribute to meiotic DSBs-homeostasis in maintaining genetically determined levels of breaks.

Topoisomerase II- and condensin-dependent breakage of MEC1ATR-sensitive fragile sites occurs independently of spindle tension, anaphase, or cytokinesis.

Fragile sites are loci of recurrent chromosome breakage in the genome. They are found in organisms ranging from bacteria to humans and are implicated in genome instability, evolution, and cancer. In budding yeast, inactivation of Mec1, a homolog of mammalian ATR, leads to chromosome breakage at fragile sites referred to as replication slow zones (RSZs). RSZs are proposed to be homologous to mammalian common fragile sites (CFSs) whose stability is regulated by ATR. Perturbation during S phase, leading to elevated levels of stalled replication forks, is necessary but not sufficient for chromosome breakage at RSZs or CFSs. To address the nature of additional event(s) required for the break formation, we examined involvement of the currently known or implicated mechanisms of endogenous chromosome breakage, including errors in replication fork restart, premature mitotic chromosome condensation, spindle tension, anaphase, and cytokinesis. Results revealed that chromosome breakage at RSZs is independent of the RAD52 epistasis group genes and of TOP3, SGS1, SRS2, MMS4, or MUS81, indicating that homologous recombination and other recombination-related processes associated with replication fork restart are unlikely to be involved. We also found spindle force, anaphase, or cytokinesis to be dispensable. RSZ breakage, however, required genes encoding condensin subunits (YCG1, YSC4) and topoisomerase II (TOP2). We propose that chromosome break formation at RSZs following Mec1 inactivation, a model for mammalian fragile site breakage, is mediated by internal chromosomal stress generated during mitotic chromosome condensation.

Regulation of fragile sites expression in budding yeast by MEC1, RRM3 and hydroxyurea.

Fragile sites are specific loci within the genome that exhibit increased tendencies for chromosome breakage. They are conserved among mammals and are also found in lower eukaryotes including yeast and fly. Many conditions, including mutations and exogenous factors, contribute to fragile site expression, but the nature of interaction among them remains elusive. Here, we investigated this by examining the combined effects of rrm3Δ, mec1 and hydroxyurea (HU), three conditions that induce fragile sites, on expression of the replication slow zone (RSZ), a type of fragile site in budding yeast. Contrary to the expectation that each factor would contribute to fragile site expression in an independent manner, we show that rrm3Δ and high concentrations of HU suppressed RSZ expression in mec1-4ts cells. Further analyses revealed that rrm3Δ suppression occurs via promotion of Sml1 degradation, whereas HU suppresses RSZ via a premature commitment to inviability. Taken together, these observations demonstrate that: (1) the yeast genome contains different types of fragile site with regard to regulation of their expression, and (2) each fragile-site-inducing condition does not act independently, but can elicit a cellular response(s) that can paradoxically prevent the expression of a specific type(s) of fragile sites.

An investigation into the relationship between vigabatrin, movement disorders, and brain magnetic resonance imaging abnormalities in children with infantile spasms.

AIM: We aimed to investigate the relationship between movement disorders, changes on brain magnetic resonance imaging (MRI), and vigabatrin therapy in children with infantile spasms. METHOD: Retrospective review and brain MRI analysis of children enrolled in the International Collaborative Infantile Spasms Study (ICISS) who developed a movement disorder on vigabatrin therapy. Comparisons were made with controls within ICISS who had no movement disorder. RESULTS: Ten of 124 infants had a movement disorder and in eight it had developed on vigabatrin therapy. Two had a movement disorder that resolved on dose-reduction of vigabatrin, one had improvement on withdrawing vigabatrin, two had resolution without any dose change, and in three it persisted despite vigabatrin withdrawal. The typical brain MRI changes associated with vigabatrin therapy were noted in two infants. Ten control infants were identified. Typical MRI changes noted with vigabatrin were noted in three controls. INTERPRETATION: It is possible that in two out of eight cases, vigabatrin was associated with the development of a movement disorder. In six out of eight cases a causal relationship was less plausible. The majority of infants treated with vigabatrin did not develop a movement disorder. MRI changes associated with vigabatrin do not appear to be specifically related to the movement disorder.

Prednisolone or tetracosactide depot for infantile epileptic spasms syndrome? A prospective analysis of data embedded within two randomised controlled trials.

OBJECTIVE: To report a prospectively planned analysis of two randomised controlled trials with embedded comparisons of prednisolone versus tetracosactide depot for the treatment of infantile epileptic spasms syndrome (IESS). METHODS: Individual patient data from patients randomly allocated to prednisolone or tetracosactide depot were analysed from two trials (UKISS, ICISS). The comparison was embedded within trials in which some patients also received vigabatrin but only patients receiving monotherapy with randomly allocated hormonal treatments are included in this analysis. The main outcome was cessation of spasms (Days 13-14 after randomisation). Lead time to treatment and underlying aetiology were taken into account. Cessation of spasms on Days 14-42 inclusive, electroclinical response (EEG Day 14), plus developmental and epilepsy outcomes (at 14 months in UKISS and 18 months in ICISS) are also reported. Minimum treatment was prednisolone 40 mg per day for two weeks or tetracosactide depot 0·5 mg IM on alternate days for two weeks, all followed by a reducing dose of prednisolone over two weeks. RESULTS: 126 infants were included in this study. On tetracosactide depot, 47 of 62 (76%) were free of spasms on Days 13-14 compared to 43 of 64 (67%) on prednisolone (difference 9%, 95% CI -7·2% to +25·2%, chi square 1·15, p = 0·28). For Day 14-42 cessation of spasms, on tetracosactide depot, 41 of 61 (67%) were free of spasms compared to 35 of 62 (56%) on prednisolone (difference 11%, 95% CI -6·4% to +28·4%, chi square 1·51, p = 0·22). There was no significant difference in mean VABS score between infants who received prednisolone compared with those who received tetracosactide depot (74·8 (SD 18·3) versus 78·0 (SD 20·2) t = -0·91 p = 0·36). The proportion with ongoing epilepsy at the time of developmental assessment was 20 of 61 (33%) in the tetracosactide group compared with 26 out of 63 (41%) in the prednisolone group (difference 8%, 95% CI -9·2% to +25·2%, Chi [2] 0·95, p = 0·33). SIGNIFICANCE: With hormone monotherapy, either prednisolone or tetracosactide depot may be recommended for infantile epileptic spasms syndrome.

The long-term risk of premature mortality in people with epilepsy.

People with epilepsy have an increased risk of premature death. The risk is highest soon after onset of seizures. We report the findings of a long-term follow-up population-based study of people with epilepsy with regards to premature mortality. The National General Practice Study of Epilepsy is a prospective study flagged at the National Health Service Information Centre in the UK. Over 1000 people with new onset seizures were followed from the mid 1980s until April 2009. Of these, 564 people were classified at 6 months as having definite epileptic seizures, 228 as having possible epileptic seizures and 220 as having febrile seizures. The remainder were excluded (n=104 because of an unknown prior diagnosis of epilepsy or neonatal seizures) or classified as not having epilepsy (n=79). At median follow-up of 22.8 years there had been 301 deaths in the cohort; 300 of these were in people with definite or possible seizures. Death certificates were obtained for all but three of those who died. The overall standardized mortality ratio for those with definite or possible epilepsy was 2.2 (95% confidence interval 1.97-2.47), and was higher in those with definite seizures (2.6). In those who were alive at 20 years follow-up, the standardized mortality ratio in the subsequent years remained significantly elevated (2.2, 95% confidence interval 1.6-3.2). Pneumonia (standardized mortality ratio 6.6, 95% confidence incidence 5.1, 8.4) was a common cause of death with a consistently elevated standardized mortality ratio throughout follow-up. The standardized mortality ratio for ischaemic heart disease was significantly elevated for the first time in the last 5 years of follow-up (3.3, 95% confidence interval 1.6-7.0). Few people died from epilepsy-related causes. The risk of premature death remains significantly elevated at 20-25 years after the index seizure despite most of the cohort being in terminal remission (defined as 5 years or more seizure-free, on or off anti-epileptic medication) at the last follow-up. Further studies are needed to explore the reasons for this long-term increase in premature mortality.

The effect of lead time to treatment and of age of onset on developmental outcome at 4 years in infantile spasms: evidence from the United Kingdom Infantile Spasms Study.

PURPOSE: Infantile spasms is a severe infantile seizure disorder. Several factors affect developmental outcome, especially the underlying etiology of the spasms. Treatment also affects outcome. Both age at onset of spasms and lead time to treatment (the time from onset of spasms to start of treatment) may be important. We investigated these factors. METHODS: Developmental assessment using Vineland Adaptive Behaviour Scales (VABS) at 4 years of age in infants enrolled in the United Kingdom Infantile Spasms Study. Date of or age at onset of spasms was obtained prospectively. Lead time to treatment was then categorized into five categories. The effects of lead time to treatment, age of onset of spasms, etiology, and treatment on developmental outcome were investigated using multiple linear regression. KEY FINDINGS: Age of onset ranged (77 infants) from <1 to 10 months (mean 5.2, standard deviation 2.1). Lead time to treatment was 7 days or less in 11, 8-14 days in 16, 15 days to 1 month in 8, 1-2 months in 15, >2 months in 21 and not known in 6. Each month of reduction in age at onset of spasms was associated with a 3.1 [95% confidence interval (CI) 0.64-5.5, p = 0.03] decrease, and each increase in category of lead time duration associated with a 3.9 (95% CI 7.3-0.4, p = 0.014) decrease in VABS, respectively. There was a significant interaction between treatment allocation and etiology with the benefit in VABS in those allocated steroid therapy being in children with no identified etiology (coefficient 29.9, p=0.004). SIGNIFICANCE: Both prompt diagnosis and prompt treatment of infantile spasms may help prevent subsequent developmental delay. Younger infants may be more at risk from the epileptic encephalopathy than older infants.

The underlying etiology of infantile spasms (West syndrome): information from the United Kingdom Infantile Spasms Study (UKISS) on contemporary causes and their classification.

PURPOSE: To examine the underlying etiology of infantile spasms from the United Kingdom Infantile Spasms Study (UKISS), using the pediatric adaptation of ICD 10. METHODS: Infants were enrolled in a randomized controlled trial or a parallel epidemiologic study. Etiological information included history, examination, and investigations. The infants were classified as proven etiology, if a neurologic disease was identified; as no identified etiology, if no neurologic disease was identified; and as not fully investigated, if a major piece of information was missing. Proven etiology was subclassified using the pediatric adaptation of ICD 10. The results were then examined to identify further methods of classification. RESULTS: Of 207 infants, 127 (61%) had proven etiology, 68 (33%) had no identified etiology, and 12 (6%) were not fully investigated. Etiologies were prenatal in 63, perinatal in 38, postnatal in 8, and 18 other. The most common etiologies were: hypoxic-ischemic encephalopathy (HIE) 21 (10%), chromosomal 16 (8%), malformations 16 (8%), stroke 16 (8%), tuberous sclerosis complex (TSC) 15 (7%), and periventricular leukomalacia or hemorrhage 11 (5%). The remaining 32 etiologies were all individually uncommon. Response to treatment is given for individual etiologies. DISCUSSION: Our method of classification allows the reporting of results by individual diseases, disease groups, or categories and is structured and clear. It avoids the use of poorly defined terms such as symptomatic and cryptogenic. It can adapt to new neurologic diseases, such as gene defects, and can be used for comparison of different groups of infants, thereby aiding meta-analysis.

Suicide in people with epilepsy: how great is the risk?

PURPOSE: Suicide is more common in populations with epilepsy, but estimates vary concerning the magnitude of the risk. We aimed to estimate the risk using meta-analysis. METHODS: A literature search identified 74 articles (76 cohorts of people with epilepsy) in whom the number of deaths by suicide in people with epilepsy and the number of person-years at risk could be estimated. Standardized mortality ratios (SMRs) with 95% confidence intervals (CIs) were calculated for each cohort, for groups of cohorts, and for the total population. RESULTS: The overall SMR was 3.3 (95% CI 2.8-3.7) based on 190 observed deaths by suicide compared with 58.4 expected. The SMR was significantly increased in people with incident or newly diagnosed epilepsy in the community (SMR 2.1), in populations with mixed prevalence and incidence cases (SMR 3.6), in those with prevalent epilepsy (SMR 4.8), in people in institutions (SMR 4.6), in people seen in tertiary care clinics (SMR 2.28), in people with temporal lobe epilepsy (SMR 6.6), in those following temporal lobe excision (SMR 13.9), and following other forms of epilepsy surgery (SMR 6.4). The SMR was significantly low overall in two community-based studies of people with epilepsy and developmental disability. DISCUSSION: We confirm that the risk of suicide is increased in most populations of people with epilepsy. Psychiatric comorbidity has been demonstrated to be a risk factor for suicide in the general population and in people with epilepsy, and such comorbidity should thus be identified and treated.

Essential Function of Mec1, the Budding Yeast ATM/ATR Checkpoint-Response Kinase, in Protein Homeostasis.

Unlike most checkpoint proteins, Mec1, an ATM/ATR kinase, is essential. We utilized mec1-4, a missense allele (E2130K) that confers diminished kinase activity, to interrogate the question. Unbiased screen for genetic interactors of mec1-4 identified numerous genes involved in proteostasis. mec1-4 confers sensitivity to heat, an amino acid analog, and Htt103Q, an aggregation-prone model peptide of Huntingtin. Oppositely, mec1-4 confers resistance to cycloheximide, a translation inhibitor. In response to heat, mec1-4 leads to widespread protein aggregation and cell death. Key components of the Mec1 signaling network, Rad53CHK1, Dun1, and Sml1, also impact survival in response to proteotoxic stress. Activation of autophagy or sml1Δ promotes aggregate resolution and rescues mec1-4 lethality. These findings show that proteostasis is a fundamental function of Mec1 and that Mec1 is likely to utilize its checkpoint response network to mediate resistance to proteotoxic stress, a role that may be conserved from yeast to mammalian cells.

Vigabatrin with hormonal treatment versus hormonal treatment alone (ICISS) for infantile spasms: 18-month outcomes of an open-label, randomised controlled trial.

BACKGROUND: Infantile spasms constitute a severe form of epileptic encephalopathy. In the International Collaborative Infantile Spasms Study (ICISS), we showed that combining vigabatrin with hormonal therapy was more effective than hormonal therapy alone at stopping spasms between days 14 and 42 of treatment. In this planned follow-up, we aimed to assess whether combination therapy was associated with improved developmental and epilepsy outcomes at 18 months of age. METHODS: In ICISS, a multicentre, open-label, randomised controlled trial, infants were enrolled from 102 hospitals (three in Australia, 11 in Germany, two in New Zealand, three in Switzerland, and 83 in the UK). Eligible infants had a clinical diagnosis of infantile spasms and a hypsarrhythmic (or similar) electroencephalogram (EEG) no more than 7 days before enrolment. Participants were randomly assigned (1:1) by a secure website to receive hormonal therapy with vigabatrin or hormonal therapy alone. If parents consented, there was an additional randomisation (1:1) of type of hormonal therapy used (prednisolone or tetracosactide depot). Block randomisation was stratified for hormonal treatment and risk of developmental impairment. Parents and clinicians were not masked to therapy, but investigators assessing epilepsy and developmental outcomes at 18 months were masked to treatment allocation. Minimum doses were oral prednisolone 10 mg four times a day or intramuscular tetracosactide depot 0·5 mg (40 IU) on alternate days with or without oral vigabatrin 100 mg/kg per day. The primary outcome at 18 months was development as assessed by the Vineland Adaptive Behaviour Scales (VABS) composite score. Secondary outcomes were the presence or absence of epileptic seizures or infantile spasms in the previous 28 days, as recorded by parents and carers, and the use of any anti-epileptic treatment (including ketogenic diet) in the previous 28 days. Analysis was by intention to treat. The trial is registered with the ISRCTN registry, number 54363174, and EudraCT, number 2006-000788-27. FINDINGS: Between March 7, 2007, and May 22, 2014, 766 infants were screened and, of those, 377 were randomly assigned to hormonal therapy with vigabatrin (n=186) or hormonal therapy alone (n=191). 362 infants were assessed for developmental and epilepsy outcomes at 18 months, 181 in each treatment group. Mean VABS scores did not differ significantly between the combination therapy group and the hormonal therapy alone group (73·9 [SE 1·3] vs 72·7 [1·4], difference -1·2 [95% CI -4·9 to 2·6], p=0·55). Presence of epilepsy at the assessment at age 18 months was similar in both treatment groups (54 [30·0%] of 180 infants who received combination therapy vs 52 [29·2%] of 178 who received hormonal therapy alone; difference 0·8% [95% CI -8·8 to 10·4], p=0·90). Presence of spasms was also similar in both treatment groups (27 [15·0%] of 180 infants on combination therapy vs 28 [15·7%] of 178 on hormonal therapy alone; difference 0·7% [95% CI -6·9 to 8·3], p=0·85). At the 18-month assessment, 158 (44·1%) of 358 infants were on some form of anti-epileptic treatment. Initial control of spasms between days 14 and 42 of treatment was associated with higher mean VABS scores at 18 months (79·1 [SE 1·2] vs 63·2 [1·1], difference 15·9 [95% CI 12·4 to 19·5], p<0·001) and with higher likelihood of absence of seizures at 18 months (in 39 [17·0%] of 229 infants who achieved spasm cessation vs 67 [51·9%] of 129 who did not; difference 34·9% [24·8 to 45·0], p<0·001). Increasing lead-time to treatment was associated with lower VABS scores (analysis of variance: F[4,354]=6·38, p<0·001) and worse epilepsy outcomes (p=0·023). INTERPRETATION: Combination therapy did not result in improved developmental or epilepsy outcomes at 18 months. However, early clinical response to treatment was associated with improved developmental and epilepsy outcomes at 18 months. Longer lead-time to treatment was associated with poorer outcomes. Rapid diagnosis and effective treatment of infantile spasms could therefore improve outcomes. FUNDING: The Castang Foundation, Bath Unit for Research in Paediatrics, National Institute of Health Research, the Royal United Hospitals Bath NHS Foundation Trust, BRONNER-BENDER Stiftung/Gernsbach, University Children's Hospital Zurich.

Safety and effectiveness of hormonal treatment versus hormonal treatment with vigabatrin for infantile spasms (ICISS): a randomised, multicentre, open-label trial.

BACKGROUND: Infantile spasms constitutes a severe infantile epilepsy syndrome that is difficult to treat and has a high morbidity. Hormonal therapies or vigabatrin are the most commonly used treatments. We aimed to assess whether combining the treatments would be more effective than hormonal therapy alone. METHODS: In this multicentre, open-label randomised trial, 102 hospitals (Australia [three], Germany [11], New Zealand [two], Switzerland [three], and the UK [83]) enrolled infants who had a clinical diagnosis of infantile spasms and a hypsarrhythmic (or similar) EEG no more than 7 days before enrolment. Participants were randomly assigned (1:1) by a secure website to receive hormonal therapy with vigabatrin or hormonal therapy alone. If parents consented, there was an additional randomisation (1:1) of type of hormonal therapy used (prednisolone or tetracosactide depot). Block randomisation was stratified for hormonal treatment and risk of developmental impairment. Parents and clinicians were not masked to therapy, but investigators assessing electro-clinical outcome were masked to treatment allocation. Minimum doses were prednisolone 10 mg four times a day or intramuscular tetracosactide depot 0·5 mg (40 IU) on alternate days with or without vigabatrin 100 mg/kg per day. The primary outcome was cessation of spasms, which was defined as no witnessed spasms on and between day 14 and day 42 from trial entry, as recorded by parents and carers in a seizure diary. Analysis was by intention to treat. The trial is registered with The International Standard Randomised Controlled Trial Number (ISRCTN), number 54363174, and the European Union Drug Regulating Authorities Clinical Trials (EUDRACT), number 2006-000788-27. FINDINGS: Between March 7, 2007, and May 22, 2014, 766 infants were screened and, of those, 377 were randomly assigned to hormonal therapy with vigabatrin (186) or hormonal therapy alone (191). All 377 infants were assessed for the primary outcome. Between days 14 and 42 inclusive no spasms were witnessed in 133 (72%) of 186 patients on hormonal therapy with vigabatrin compared with 108 (57%) of 191 patients on hormonal therapy alone (difference 15·0%, 95% CI 5·1-24·9, p=0·002). Serious adverse reactions necessitating hospitalisation occurred in 33 infants (16 on hormonal therapy alone and 17 on hormonal therapy with vigabatrin). The most common serious adverse reaction was infection occurring in five infants on hormonal therapy alone and four on hormonal therapy with vigabatrin. There were no deaths attributable to treatment. INTERPRETATION: Hormonal therapy with vigabatrin is significantly more effective at stopping infantile spasms than hormonal therapy alone. The 4 week period of spasm cessation required to achieve a primary clinical response to treatment suggests that the effect seen might be sustained, but this needs to be confirmed at the 18 month follow-up. FUNDING: The Castang Foundation, Bath Unit for Research in Paediatrics, National Institute of Health Research, the Royal United Hospitals Bath NHS Foundation Trust, the BRONNER-BENDUNG Stifung/Gernsbach, and University Children's Hospital Zurich.

Response to the editorial by Dr Geraghty.

This article is written in response to the linked editorial by Dr Geraghty about the adaptive Pacing, graded Activity and Cognitive behaviour therapy; a randomised Evaluation (PACE) trial, which we led, implemented and published. The PACE trial compared four treatments for people diagnosed with chronic fatigue syndrome. All participants in the trial received specialist medical care. The trial found that adding cognitive behaviour therapy or graded exercise therapy to specialist medical care was as safe as, and more effective than, adding adaptive pacing therapy or specialist medical care alone. Dr Geraghty has challenged these findings. In this article, we suggest that Dr Geraghty's views are based on misunderstandings and misrepresentations of the PACE trial; these are corrected.

The United Kingdom Infantile Spasms Study (UKISS) comparing hormone treatment with vigabatrin on developmental and epilepsy outcomes to age 14 months: a multicentre randomised trial.

BACKGROUND: Infantile spasms is a severe infantile seizure disorder that is difficult to treat and has a high morbidity. Absence of spasms on days 13 and 14 after randomisation is more common in infants allocated hormone treatments than in those allocated vigabatrin. We sought to assess whether early control of spasms is associated with improved developmental or epilepsy outcomes. METHODS: Infants enrolled in the United Kingdom Infantile Spasms Study (UKISS) were randomly assigned hormone treatment (n=55) or vigabatrin (n=52) and were followed up until clinical assessment at 12-14 months of age. We assessed neurodevelopment with the Vineland adaptive behaviour scales (VABS) at 14 months of age on an intention to treat basis. FINDINGS: Of 107 infants enrolled, five died and 101 survivors reached both follow-up assessments. Absence of spasms at final clinical assessment (hormone 41/55 [75%] vs vigabatrin 39/51 [76%]) was similar in each treatment group (difference 1.9%, 95% CI -18.3% to 14.4%; chi(2)=0.05; p=0.82). Mean VABS score did not differ significantly (hormone 78.6 [SD 16.8] vs vigabatrin 77.5 [SD 12.7]; difference 1.0, 95% CI -4.9 to 7.0; t(99)=0.35, p=0.73). In infants with no identified underlying aetiology, the mean VABS score was higher in those allocated hormone treatment than in those allocated vigabatrin (88.2 [17.3] vs 78.9 [14.3]; difference 9.3, 95% CI 1.2 to 17.3; t(95)=2.28, p=0.025). INTERPRETATION: Hormone treatment controls spasms better than does vigabatrin initially, but not at 12-14 months of age. Better initial control of spasms by hormone treatment in those with no identified underlying aetiology may lead to improved developmental outcome.

The United Kingdom Infantile Spasms Study comparing vigabatrin with prednisolone or tetracosactide at 14 days: a multicentre, randomised controlled trial.

BACKGROUND: Infantile spasms, which comprise a severe infantile seizure disorder, have a high morbidity and are difficult to treat. Hormonal treatments (adrenocorticotropic hormone and prednisolone) have been the main therapy for decades, although little evidence supports their use. Vigabatrin has been recorded to have a beneficial effect in this disorder. We aimed to compare the effects of vigabatrin with those of prednisolone and tetracosactide in the treatment of infantile spasms. METHODS: The United Kingdom Infantile Spasms Study assessed these treatments in a multicentre, randomised controlled trial in 150 hospitals in the UK. The primary outcome was cessation of spasms on days 13 and 14. Minimum doses were vigabatrin 100 mg/kg per day, oral prednisolone 40 mg per day, or intramuscular tetracosactide depot 0.5 mg (40 IU) on alternate days. Analysis was by intention to treat. FINDINGS: Of 208 infants screened and assessed, 107 were randomly assigned to vigabatrin (n=52) or hormonal treatments (prednisolone n=30, tetracosactide n=25). None was lost to follow-up. Proportions with no spasms on days 13 and 14 were: 40 (73%) of 55 infants assigned hormonal treatments (prednisolone 21/30 [70%], tetracosactide 19/25 [76%]) and 28 (54%) of 52 infants assigned vigabatrin (difference 19%, 95% CI 1%-36%, p=0.043). Two infants allocated tetracosactide and one allocated vigabatrin received prednisolone. Adverse events were reported in 30 (55%) of 55 infants on hormonal treatments and 28 (54%) of 52 infants on vigabatrin. No deaths were recorded. INTERPRETATION: Cessation of spasms was more likely in infants given hormonal treatments than those given vigabatrin. Adverse events were common with both treatments.

Expression of Ki67, PCNA and the chromosome replication licensing protein Mcm2 in glial cells of the ageing human hippocampus increases with the burden of Alzheimer-type pathology.

Cell-cycle mechanisms may be aberrantly reactivated in the ageing brain and associated with the development of pathology, including Alzheimer's disease. Activation of cell-cycle mechanisms in glia has, however, been little studied. Our aim was to determine whether expression of a marker for chromosomal replication licensing, Mcm2, occurs in glia of the ageing hippocampus, and to compare its expression to that of Ki67 and PCNA. Blocks of hippocampus were obtained from 19 elderly brains derived from the MRC-CFAS neuropathology cohort, which included a spectrum of Alzheimer-type pathology, semi-quantified using the Braak scoring system for neurofibrillary tangles. Mcm2, PCNA and Ki67 were detected immunohistochemically. Expression of Mcm2, Ki67 and PCNA was observed in glial cells and neurons, with a trend to increased expression in association with higher burdens of Alzheimer-type pathology. Mcm2 expression in glial cells showed a significant linear trend across Braak stages (P = 0.043). This study demonstrates that grey and white matter glial cells show expression of cell-cycle markers in the ageing brain and that re-licensing for chromosomal replication is a component of the mechanisms activated. A quantitative relationship to the burden of Alzheimer-type pathology suggests that cell-cycle re-entry in glial cells may be important in the pathogenesis of age-related neurodegeneration.