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1.
Eur J Paediatr Neurol ; 42: 110-116, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36621063

ABSTRACT

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.


Subject(s)
Epilepsy , Spasms, Infantile , Infant , Humans , Prednisolone/therapeutic use , Cosyntropin/therapeutic use , Anticonvulsants/therapeutic use , Spasms, Infantile/drug therapy , Vigabatrin/therapeutic use , Epilepsy/drug therapy , Syndrome , Spasm , Treatment Outcome , Randomized Controlled Trials as Topic
2.
Epilepsia ; 60(9): 1861-1869, 2019 09.
Article in English | MEDLINE | ID: mdl-31418851

ABSTRACT

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.


Subject(s)
Malformations of Cortical Development/complications , Spasms, Infantile/etiology , Stroke/complications , Anticonvulsants/therapeutic use , Female , Humans , Infant , Male , Malformations of Cortical Development/physiopathology , Prednisolone/therapeutic use , Spasms, Infantile/drug therapy , Spasms, Infantile/physiopathology , Stroke/physiopathology , Vigabatrin/therapeutic use
3.
Lancet Child Adolesc Health ; 2(10): 715-725, 2018 10.
Article in English | MEDLINE | ID: mdl-30236380

ABSTRACT

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.


Subject(s)
Cosyntropin/therapeutic use , Prednisolone/therapeutic use , Spasms, Infantile/drug therapy , Vigabatrin/therapeutic use , Cosyntropin/administration & dosage , Drug Administration Schedule , Drug Therapy, Combination , Electroencephalography , Female , Humans , Infant , Male , Prednisolone/administration & dosage , Spasms, Infantile/prevention & control , Vigabatrin/administration & dosage
4.
Dev Cell ; 46(4): 495-503.e2, 2018 08 20.
Article in English | MEDLINE | ID: mdl-30130531

ABSTRACT

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.


Subject(s)
Cell Cycle Proteins/metabolism , Intracellular Signaling Peptides and Proteins/metabolism , Protein Serine-Threonine Kinases/metabolism , Proteostasis/physiology , Saccharomyces cerevisiae Proteins/metabolism , Checkpoint Kinase 2/metabolism , DNA Damage/physiology , Intracellular Signaling Peptides and Proteins/genetics , Phosphorylation , Protein Serine-Threonine Kinases/genetics , Saccharomyces cerevisiae , Saccharomyces cerevisiae Proteins/genetics , Saccharomycetales
5.
J Health Psychol ; 22(9): 1113-1117, 2017 08.
Article in English | MEDLINE | ID: mdl-28805524

ABSTRACT

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.


Subject(s)
Dissent and Disputes , Fatigue Syndrome, Chronic/therapy , Randomized Controlled Trials as Topic , Cognitive Behavioral Therapy , Exercise Therapy , Fatigue Syndrome, Chronic/psychology , Humans , Treatment Outcome
6.
Lancet Neurol ; 16(1): 33-42, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27838190

ABSTRACT

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.


Subject(s)
Anticonvulsants/therapeutic use , Hormones/therapeutic use , Spasms, Infantile/drug therapy , Treatment Outcome , Vigabatrin/therapeutic use , Cosyntropin/therapeutic use , Drug Administration Schedule , Drug Therapy, Combination , Electroencephalography , Female , Follow-Up Studies , Humans , Infant , Male , Prednisolone/therapeutic use
8.
J Neurol Neurosurg Psychiatry ; 87(8): 843-50, 2016 Aug.
Article in English | MEDLINE | ID: mdl-26780937

ABSTRACT

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.


Subject(s)
Epilepsy/diagnosis , Epilepsy/mortality , Seizures/diagnosis , Seizures/mortality , Adolescent , Adult , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prognosis , Prospective Studies , Young Adult
10.
Lancet Psychiatry ; 2(12): 1067-74, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26521770

ABSTRACT

BACKGROUND: The PACE trial found that, when added to specialist medical care (SMC), cognitive behavioural therapy (CBT), or graded exercise therapy (GET) were superior to adaptive pacing therapy (APT) or SMC alone in improving fatigue and physical functioning in people with chronic fatigue syndrome 1 year after randomisation. In this pre-specified follow-up study, we aimed to assess additional treatments received after the trial and investigate long-term outcomes (at least 2 years after randomisation) within and between original treatment groups in those originally included in the PACE trial. METHODS: The PACE trial was a parallel-group randomised controlled trial of patients meeting Oxford criteria for chronic fatigue syndrome who were recruited from six secondary care clinics in the UK between March 18, 2005, and Nov 28, 2008. Participants were randomly allocated to receive SMC alone or plus APT, CBT, or GET. Primary outcomes (were fatigue measured with Chalder fatigue questionnaire score and physical functioning with short form-36 subscale score, assessed 1 year after randomisation. In this long-term follow-up, we sent postal questionnaires to assess treatment received after the trial and outcomes a minimum of 2 years after randomisation. We assessed long-term differences in outcomes within and between originally randomised groups. The PACE trial is registered at http://isrctn.org, number ISRCTN54285094. FINDINGS: Between May 8, 2008, and April 26, 2011, 481 (75%) participants from the PACE trial returned questionnaires. Median time from randomisation to return of long-term follow-up assessment was 31 months (IQR 30-32; range 24-53). 210 (44%) participants received additional treatment (mostly CBT or GET) after the trial; with participants originally assigned to SMC alone (73 [63%] of 115) or APT (60 [50%] of 119) more likely to seek treatment than those originally assigned to GET (41 [32%] of 127) or CBT (36 [31%] of 118; p<0·0001). Improvements in fatigue and physical functioning reported by participants originally assigned to CBT and GET were maintained (within-group comparison of fatigue and physical functioning, respectively, at long-term follow-up as compared with 1 year: CBT -2·2 [95% CI -3·7 to -0·6], 3·3 [0·02 to 6·7]; GET -1·3 [-2·7 to 0·1], 0·5 [-2·7 to 3·6]). Participants allocated to APT and to SMC alone in the trial improved over the follow-up period compared with 1 year (fatigue and physical functioning, respectively: APT -3·0 [-4·4 to -1·6], 8·5 [4·5 to 12·5]; SMC -3·9 [-5·3 to -2·6], 7·1 [4·0 to 10·3]). There was little evidence of differences in outcomes between the randomised treatment groups at long-term follow-up. INTERPRETATION: The beneficial effects of CBT and GET seen at 1 year were maintained at long-term follow-up a median of 2·5 years after randomisation. Outcomes with SMC alone or APT improved from the 1 year outcome and were similar to CBT and GET at long-term follow-up, but these data should be interpreted in the context of additional therapies having being given according to physician choice and patient preference after the 1 year trial final assessment. Future research should identify predictors of response to CBT and GET and also develop better treatments for those who respond to neither. FUNDING: UK Medical Research Council, Department of Health for England, Scottish Chief Scientist Office, Department for Work and Pensions, National Institute for Health Research (NIHR), NIHR Biomedical Research Centre for Mental Health at South London and Maudsley NHS Foundation Trust, King's College London.


Subject(s)
Fatigue Syndrome, Chronic/rehabilitation , Adult , Female , Follow-Up Studies , Humans , Male , Middle Aged , Rehabilitation/methods , Time Factors , Treatment Outcome
11.
PLoS One ; 10(7): e0134297, 2015.
Article in English | MEDLINE | ID: mdl-26225562

ABSTRACT

A hallmark of the conserved ATM/ATR signalling is its ability to mediate a wide range of functions utilizing only a limited number of adaptors and effector kinases. During meiosis, Tel1 and Mec1, the budding yeast ATM and ATR, respectively, rely on a meiotic adaptor protein Hop1, a 53BP1/Rad9 functional analog, and its associated kinase Mek1, a CHK2/Rad53-paralog, to mediate multiple functions: control of the formation and repair of programmed meiotic DNA double strand breaks, enforcement of inter-homolog bias, regulation of meiotic progression, and implementation of checkpoint responses. Here, we present evidence that the multi-functionality of the Tel1/Mec1-to-Hop1/Mek1 signalling depends on stepwise activation of Mek1 that is mediated by Tel1/Mec1 phosphorylation of two specific residues within Hop1: phosphorylation at the threonine 318 (T318) ensures the transient basal level Mek1 activation required for viable spore formation during unperturbed meiosis. Phosphorylation at the serine 298 (S298) promotes stable Hop1-Mek1 interaction on chromosomes following the initial phospho-T318 mediated Mek1 recruitment. In the absence of Dmc1, the phospho-S298 also promotes Mek1 hyper-activation necessary for implementing meiotic checkpoint arrest. Taking these observations together, we propose that the Hop1 phospho-T318 and phospho-S298 constitute key components of the Tel1/Mec1- based meiotic recombination surveillance (MRS) network and facilitate effective coupling of meiotic recombination and progression during both unperturbed and challenged meiosis.


Subject(s)
DNA-Binding Proteins/metabolism , Meiosis , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae/metabolism , DNA Repair , DNA-Binding Proteins/chemistry , Phosphorylation , Saccharomyces cerevisiae Proteins/chemistry , Serine/metabolism , Temperature
12.
Trials ; 16: 104, 2015 Mar 23.
Article in English | MEDLINE | ID: mdl-25872927

ABSTRACT

BACKGROUND: The move towards increased transparency around clinical trials is welcome. Much focus has been on under-reporting of trials and access to individual patient data to allow independent verification of findings. There are many other good reasons for data sharing from clinical trials. We describe some key issues in data sharing, including the challenges of open access to data. These include issues in consent and disclosure; risks in identification, including self-identification; risks in distorting data to prevent self-identification; and risks in analysis. These risks have led us to develop a controlled access policy, which safeguards the rights of patients entered in our trials, guards the intellectual property rights of the original researchers who designed the trial and collected the data, provides a barrier against unnecessary duplication, and ensures that researchers have the necessary resources and skills to analyse the data. METHODS: We briefly discuss the practicalities of our current approach to data sharing, including ensuring that data are discoverable and how to deal with old studies. We describe data sharing activities at the MRC Clinical Trials Unit. RESULTS: One hundred and three data sharing activities were logged from 2012 to 2014 from external and internal applicants. The motivations are varied, but none have been for replication of the primary results. CONCLUSIONS: For any request to share data, we note the important role of independent reviewers as well as reviewers who know the study well, and present some of the key questions that all reviewers should ask when deciding whether a request is reasonable. We consider the responsibilities of all parties. We highlight the potential for opportunity costs. Clinical trial data should be shared for reasonable requests but there are many practical issues that must be explicitly considered.


Subject(s)
Access to Information , Clinical Trials as Topic/methods , Databases, Factual , Information Dissemination , Research Design , Cooperative Behavior , Data Anonymization , Disclosure , Humans , Informed Consent , Policy Making
13.
PLoS Genet ; 9(11): e1003931, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24244194

ABSTRACT

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.


Subject(s)
Chromosome Fragile Sites/genetics , DNA Replication/genetics , Mitosis/genetics , Chromosome Breakage/drug effects , Chromosome Fragile Sites/drug effects , DNA Replication/drug effects , Hydroxyurea/pharmacology , Mutation , Recombination, Genetic/drug effects , Recombination, Genetic/genetics , Saccharomyces cerevisiae/genetics
14.
Trials ; 14: 386, 2013 Nov 13.
Article in English | MEDLINE | ID: mdl-24225069

ABSTRACT

BACKGROUND: The publication of protocols by medical journals is increasingly becoming an accepted means for promoting good quality research and maximising transparency. Recently, Finfer and Bellomo have suggested the publication of statistical analysis plans (SAPs).The aim of this paper is to make public and to report in detail the planned analyses that were approved by the Trial Steering Committee in May 2010 for the principal papers of the PACE (Pacing, graded Activity, and Cognitive behaviour therapy: a randomised Evaluation) trial, a treatment trial for chronic fatigue syndrome. It illustrates planned analyses of a complex intervention trial that allows for the impact of clustering by care providers, where multiple care-providers are present for each patient in some but not all arms of the trial. RESULTS: The trial design, objectives and data collection are reported. Considerations relating to blinding, samples, adherence to the protocol, stratification, centre and other clustering effects, missing data, multiplicity and compliance are described. Descriptive, interim and final analyses of the primary and secondary outcomes are then outlined. CONCLUSIONS: This SAP maximises transparency, providing a record of all planned analyses, and it may be a resource for those who are developing SAPs, acting as an illustrative example for teaching and methodological research. It is not the sum of the statistical analysis sections of the principal papers, being completed well before individual papers were drafted. TRIAL REGISTRATION: ISRCTN54285094 assigned 22 May 2003; First participant was randomised on 18 March 2005.


Subject(s)
Adaptation, Physiological , Cognitive Behavioral Therapy/methods , Exercise Therapy/methods , Fatigue Syndrome, Chronic/therapy , Combined Modality Therapy , Cost-Benefit Analysis , Data Collection , Humans , Outcome Assessment, Health Care , Research Design , Sample Size
15.
PLoS Genet ; 9(6): e1003545, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23825959

ABSTRACT

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.


Subject(s)
DNA Breaks, Double-Stranded , Intracellular Signaling Peptides and Proteins/genetics , Meiosis , Protein Serine-Threonine Kinases/genetics , Recombinases/genetics , Saccharomyces cerevisiae Proteins/genetics , Chromatin , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Down-Regulation , Endodeoxyribonucleases/genetics , Endodeoxyribonucleases/metabolism , Intracellular Signaling Peptides and Proteins/metabolism , Protein Serine-Threonine Kinases/metabolism , Recombinases/metabolism , Recombination, Genetic , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae Proteins/metabolism , Synaptonemal Complex/genetics , Transcription Factors/genetics , Transcription Factors/metabolism
16.
Dev Med Child Neurol ; 55(9): 862-7, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23789722

ABSTRACT

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.


Subject(s)
Anticonvulsants/adverse effects , Brain/pathology , Movement Disorders/etiology , Spasms, Infantile/complications , Spasms, Infantile/drug therapy , Vigabatrin/adverse effects , Anticonvulsants/administration & dosage , Basal Ganglia/pathology , Brain/drug effects , Brain Stem/pathology , Cerebellum/pathology , Female , Globus Pallidus/pathology , Humans , Infant , Magnetic Resonance Imaging , Male , Movement Disorders/pathology , Retrospective Studies , Spasms, Infantile/pathology , Vigabatrin/administration & dosage
17.
PLoS Genet ; 8(10): e1002978, 2012.
Article in English | MEDLINE | ID: mdl-23133392

ABSTRACT

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.


Subject(s)
Adenosine Triphosphatases/metabolism , Anaphase/physiology , Chromosome Breakage , Chromosome Fragile Sites , Cytokinesis/physiology , DNA Topoisomerases, Type II/metabolism , DNA-Binding Proteins/metabolism , Intracellular Signaling Peptides and Proteins/metabolism , Multiprotein Complexes/metabolism , Protein Serine-Threonine Kinases/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Spindle Apparatus , DNA Replication , Mitosis/physiology , Protein Binding , Saccharomycetales/genetics , Saccharomycetales/metabolism
18.
PLoS One ; 7(8): e40808, 2012.
Article in English | MEDLINE | ID: mdl-22870204

ABSTRACT

BACKGROUND: The PACE trial compared the effectiveness of adding adaptive pacing therapy (APT), cognitive behaviour therapy (CBT), or graded exercise therapy (GET), to specialist medical care (SMC) for patients with chronic fatigue syndrome. This paper reports the relative cost-effectiveness of these treatments in terms of quality adjusted life years (QALYs) and improvements in fatigue and physical function. METHODS: Resource use was measured and costs calculated. Healthcare and societal costs (healthcare plus lost production and unpaid informal care) were combined with QALYs gained, and changes in fatigue and disability; incremental cost-effectiveness ratios (ICERs) were computed. RESULTS: SMC patients had significantly lower healthcare costs than those receiving APT, CBT and GET. If society is willing to value a QALY at £30,000 there is a 62.7% likelihood that CBT is the most cost-effective therapy, a 26.8% likelihood that GET is most cost effective, 2.6% that APT is most cost-effective and 7.9% that SMC alone is most cost-effective. Compared to SMC alone, the incremental healthcare cost per QALY was £18,374 for CBT, £23,615 for GET and £55,235 for APT. From a societal perspective CBT has a 59.5% likelihood of being the most cost-effective, GET 34.8%, APT 0.2% and SMC alone 5.5%. CBT and GET dominated SMC, while APT had a cost per QALY of £127,047. ICERs using reductions in fatigue and disability as outcomes largely mirrored these findings. CONCLUSIONS: Comparing the four treatments using a health care perspective, CBT had the greatest probability of being the most cost-effective followed by GET. APT had a lower probability of being the most cost-effective option than SMC alone. The relative cost-effectiveness was even greater from a societal perspective as additional cost savings due to reduced need for informal care were likely.


Subject(s)
Cognitive Behavioral Therapy/economics , Exercise Therapy/economics , Fatigue Syndrome, Chronic/economics , Fatigue Syndrome, Chronic/therapy , Adult , Cognitive Behavioral Therapy/methods , Costs and Cost Analysis , Exercise Therapy/methods , Female , Humans , Male , Middle Aged , United Kingdom
19.
Epilepsia ; 52(7): 1359-64, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21668442

ABSTRACT

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.


Subject(s)
Child Development , Spasms, Infantile/diagnosis , Age of Onset , Anticonvulsants/therapeutic use , Child Development/drug effects , Child Development/physiology , Cosyntropin/therapeutic use , Early Diagnosis , Humans , Infant , Infant, Newborn , Linear Models , Prednisolone/therapeutic use , Prognosis , Spasms, Infantile/drug therapy , Spasms, Infantile/etiology , Spasms, Infantile/physiopathology , United Kingdom , Vigabatrin/therapeutic use
20.
Brain ; 134(Pt 2): 388-95, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21278406

ABSTRACT

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.


Subject(s)
Epilepsy/mortality , Risk Assessment/methods , Seizures, Febrile/mortality , Age Distribution , Cause of Death , Epilepsy/epidemiology , Female , Follow-Up Studies , Humans , Male , Mortality , Risk Factors , Seizures, Febrile/complications , Seizures, Febrile/epidemiology , United Kingdom/epidemiology
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