We review the development of several new approaches for extending the performance of Brillouin based slow light systems. In particular we describe the use of cavity effects to enhance the achievable delays, gain saturation to decouple the delay and associated signal gain, and the use of tailored pump beams to effect reshaping and retiming of periodic signals

Datta, Soumitra

Kennedy, Eilis

Kumar, Ajit

English

PubMed

Crossref

New Approaches to Extending the Performance of Brillouin Based Slow Light Systems

Tavistock and Portman E-Prints Online

  Tavistock and Portman E-Prints Online      JOURNAL ARTICLE   Original citation: Kennedy, Eilis and Kumar, Ajit and Datta, Soumitra (2007) Antipsychotic medication for childhood-onset schizophrenia. Schizophrenia Bulletin, 33 (5). pp. 1082-1083. ISSN 0586-7614   © 2007  Eilis Kennedy  This version available at: http://taviporttest.da.ulcc.ac.uk/  Available in Tavistock and Portman E-Prints Online: Oct 2009 The Trust has developed the Repository  so that users may access the clinical, academic  and research work of the Trust.   Copyright © and Moral Rights for the papers on this site are retained by the individual authors and/or other copyright owners. Users may download and/or print one copy of any article(s) in Tavistock and Portman E-Prints Online to facilitate their private study or for non-commercial research. You may not engage in further distribution of the material or use it for any profit-making activities or any commercial gain. You may freely distribute the URL (http://taviporttest.da.ulcc.ac.uk/) of  Tavistock and Portman E-Prints Online.  This document is the published version of ‘Antipsychotic medication for childhood-onset schizophrenia’.   It is freely available online.  You are encouraged to consult the remainder of this publication if you wish to cite from it.      Antipsychotic Medication for Childhood-Onset SchizophreniaEilis Kennedy1,2, Ajit Kumar3, and Soumitra S. Datta42Child andFamilyDepartment, TavistockClinic, 120Belsize Lane,LondonNW35BA,UK; 3Academic unit of Psychiatry, Leeds,UK;4Department of Child and Adolescent Psychiatry, RoyalManchester Children’s Hospital, Manchester, UKKey words: cochrane/childhood onset/schizophreniaChildhood-onset schizophrenia is defined as schizophre-nia with onset prior to the age of 13 years. Although it israre, those who suffer from schizophrenia at an early ageappear to have a clinically severe form of the illness witha poor long-term prognosis. Antipsychotic medication isone way of managing this rare but serious mental illness.A new Cochrane review examines antipsychotic medica-tion for childhood-onset schizophrenia.1ObjectiveTo determine the effects of antipsychotic medication inthe treatment of childhood-onset schizophrenia.Search StrategyWe searched the Cochrane Schizophrenia Group TrialsRegister (February 2007), inspected references of all iden-tified studies for further trials, and contacted relevantpharmaceutical companies and authors of trials for addi-tional information.Selection CriteriaWe included all randomized clinical trials involvingchildren and young people with a diagnosis of childhood-onset schizophrenia (ie, with a diagnosis of schizophre-nia before the age of 13) comparing any antipsychoticdrug with another antipsychotic or placebo.Data Collection and AnalysisStudies were reliably selected, quality assessed, and dataextracted. For homogenous dichotomous data, we calcu-lated random effects, relative risk (RR) and its 95% con-fidence interval (CI), and, where appropriate, numberneeded to treat on an intention-to-treat basis. For normalcontinuous data, we calculated the weighted meandifference (WMD).Main ResultsFrom a total of 2062 citations, 6 relevant trials were iden-tified. These studies were small (total N = 256 partici-pants) and short (all duration 12 weeks or less) andreported data for 3 comparisons (atypical vs. typical,atypical vs atypical, and typical vs. typical antipsychoticdrugs), only one of which (atypical vs. typical) was to sug-gest differences between treatment groups.A few results from one study favored the atypicalantipsychotic clozapine over haloperidol for treatingtreatment-resistant childhood-onset schizophrenia (n = 21,WMD children’s global assesment scale 17.00, CI 7.74–26.26; n = 21, WMD Bunney-Hamburg Psychosis RatingScale 3.60, CI 6.64 to 0.56). Participants on cloza-pine, however, were 3 times more likely to have drowsi-ness (1 randomized controlled trial [RCT], n = 21, RR 3.3,CI 1.2–8.9, number needed to harm 2, CI 2–17) and halfof the children receiving clozapine in this small shortstudy experienced neutropenia (1 RCT, n = 21, RR 12,CI 0.75–193; figure 1).Reviewers’ ConclusionsThere are few relevant trials and, presently, little conclu-sive evidence regarding the effects of antipsychotic med-ication for those with the rare but difficult problem ofvery early-onset schizophrenia. Some benefits were iden-tified in using the atypical antipsychotic clozapine com-pared with haloperidol, but the benefits were offset by anincreased risk of serious adverse effects.Implications for PracticeAs yet there are few data to support the use of one an-tipsychotic medication over another in the treatmentof schizophrenia with onset in childhood. The superiorityof atypical antipsychotic medications over typical anti-psychotic drugs is not reflected in studies using typicalmedications such as chlorpromazine as the comparatormedication, rather than haloperidol. Routine practicemay be best within the context of an evaluative trial.1To whom correspondence should be addressed; tel: 0207-435-7111, fax: 0207-447-3733, e-mail: EKennedy@tavi-port.nhs.uk.Schizophrenia Bulletin vol. 33 no. 5 pp. 1082–1083, 2007doi:10.1093/schbul/sbm080Advance Access publication on August 1, 2007 The Author 2007. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved.For permissions, please email: journals.permissions@oxfordjournals.org.1082Implications for ResearchFurther RCTs with larger samples and longer treatmentdurationareneededtoevaluatetheeffectivenessandsafetyofantipsychoticmedication in the treatmentof childhood-onsetschizophrenia.Therehasbeennosignificant increasein thenumber of trials in the last 3 decades possibly reflect-ing the challenges of undertaking research with this agegroup.Given the relative rarity of childhood-onset schizo-phrenia, future treatment studies will require multicentercollaboration and extensive case-finding efforts.AcknowledgmentsWe would like to thank the Cochrane SchizophreniaGroup for their help and support with this review.Disclosures: None.Reference1. Kennedy E, Kumar A, Datta SS. Antipsychotic medication forchildhood-onset schizophrenia. Cochrane Database Syst Rev;2007;Disc issue 3. Chichester, UK: John Wiley & sons.Fig. 1. Clozapine vs Haloperidol—Neutropenia.1083Antipsychotic Medication for Childhood-Onset Schizophrenia