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1.
JCI Insight ; 3(19)2018 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-30282826

RESUMO

BACKGROUND: Type 1 diabetes (T1D) results from loss of immune regulation, leading to the development of autoimmunity to pancreatic ß cells, involving autoreactive T effector cells (Teffs). Tregs, which prevent autoimmunity, require IL-2 for maintenance of immunosuppressive functions. Using a response-adaptive design, we aimed to determine the optimal regimen of aldesleukin (recombinant human IL-2) to physiologically enhance Tregs while limiting expansion of Teffs. METHODS: DILfrequency is a nonrandomized, open-label, response-adaptive study of participants, aged 18-70 years, with T1D. The initial learning phase allocated 12 participants to 6 different predefined regimens. Then, 3 cohorts of 8 participants were sequentially allocated dose frequencies, based on repeated interim analyses of all accumulated trial data. The coprimary endpoints were percentage change in Tregs and Teffs and CD25 (α subunit of the IL-2 receptor) expression by Tregs, from baseline to steady state. RESULTS: Thirty-eight participants were enrolled, with thirty-six completing treatment. The optimal regimen to maintain a steady-state increase in Tregs of 30% and CD25 expression of 25% without Teff expansion is 0.26 × 106 IU/m2 (95% CI -0.007 to 0.485) every 3 days. Tregs and CD25 were dose-frequency responsive, Teffs were not. The commonest adverse event was injection site reaction (464 of 694 events). CONCLUSIONS: Using a response-adaptive design, aldesleukin treatment can be optimized. Our methodology can generally be employed to immediately access proof of mechanism, thereby leading to more efficient and safe drug development. TRIAL REGISTRATION: International Standard Randomised Controlled Trial Number Register, ISRCTN40319192; ClinicalTrials.gov, NCT02265809. FUNDING: Sir Jules Thorn Trust, the Swiss National Science Foundation, Wellcome, JDRF, and NIHR Cambridge Biomedical Research Centre.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Interleucina-2/análogos & derivados , Linfócitos T Reguladores/efeitos dos fármacos , Adolescente , Adulto , Idoso , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/imunologia , Relação Dose-Resposta a Droga , Esquema de Medicação , Estudos de Viabilidade , Feminino , Humanos , Interleucina-2/administração & dosagem , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/administração & dosagem , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Resultado do Tratamento , Adulto Jovem
2.
BMJ Open ; 8(9): e022452, 2018 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-30224390

RESUMO

INTRODUCTION: Inflammation and dysregulated immune responses play a crucial role in atherosclerosis, underlying ischaemic heart disease (IHD) and acute coronary syndromes (ACSs). Immune responses are also major determinants of the postischaemic injury in myocardial infarction. Regulatory T cells (CD4+CD25+FOXP3+; Treg) induce immune tolerance and preserve immune homeostasis. Recent in vivo studies suggested that low-dose interleukin-2 (IL-2) can increase Treg cell numbers. Aldesleukin is a human recombinant form of IL-2 that has been used therapeutically in several autoimmune diseases. However, its safety and efficacy is unknown in the setting of coronary artery disease. METHOD AND ANALYSIS: Low-dose interleukin-2 in patients with stable ischaemic heart disease and acute coronary syndromes is a single-centre, first-in-class, dose-escalation, two-part clinical trial. Patients with stable IHD (part A) and ACS (part B) will be randomised to receive either IL-2 (aldesleukin; dose range 0.3-3×106 IU) or placebo once daily, given subcutaneously, for five consecutive days. Part A will have five dose levels with five patients in each group. Group 1 will receive a dose of 0.3×106 IU, while the dose for the remaining four groups will be determined on completion of the preceding group. Part B will have four dose levels with eight patients in each group. The dose of the first group will be based on part A. Doses for each of the subsequent three groups will similarly be determined after completion of the previous group. The primary endpoint is safety and tolerability of aldesleukin and to determine the dose that increases mean circulating Treg levels by at least 75%. ETHICS AND DISSEMINATION: The study received a favourable opinion by the Greater Manchester Central Research Ethics Committee, UK (17/NW/0012). The results of this study will be reported through peer-reviewed journals, conference presentations and an internal organisational report. TRIAL REGISTRATION NUMBER: NCT03113773; Pre-results.


Assuntos
Síndrome Coronariana Aguda/tratamento farmacológico , Fatores Imunológicos/efeitos adversos , Interleucina-2/análogos & derivados , Isquemia Miocárdica/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , Linfócitos T Reguladores/efeitos dos fármacos , Síndrome Coronariana Aguda/sangue , Proteína C-Reativa/metabolismo , Ensaios Clínicos Fase I como Assunto , Ensaios Clínicos Fase II como Assunto , Método Duplo-Cego , Humanos , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/sangue , Interleucina-2/administração & dosagem , Interleucina-2/efeitos adversos , Interleucina-2/sangue , Interleucina-6/sangue , Contagem de Linfócitos , Isquemia Miocárdica/sangue , Peptídeo Natriurético Encefálico/sangue , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/sangue , Troponina/sangue
3.
Sleep ; 41(7)2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29722893

RESUMO

Sleep is regulated by a homeostatic process which in the two-process model of human sleep regulation is represented by electroencephalogram slow-wave activity (SWA). Many studies of acute manipulation of wake duration have confirmed the precise homeostatic regulation of SWA in rodents and humans. However, some chronic sleep restriction studies in rodents show that the sleep homeostatic response, as indexed by SWA, is absent or diminishes suggesting adaptation occurs. Here, we investigate the response to 7 days of sleep restriction (6 hr time in bed) and extension (10 hr time in bed) as well as the response to subsequent total sleep deprivation in 35 healthy participants in a cross-over design. The homeostatic response was quantified by analyzing sleep structure and SWA measures. Sleep restriction resulted primarily in a reduction of rapid eye movement (REM) sleep. SWA and accumulated SWA (slow-wave energy, SWE) were not much affected by sleep extension/restriction. The SWA responses did not diminish significantly in the course of the intervention and did not deviate significantly from the predictions of the two-process model. The response to total sleep deprivation consisted of an increase in SWA and rise rate of SWA and SWE and did not differ between the two conditions. The data show that changes in sleep duration within an ecologically relevant range have a marked effect on REM sleep and that SWA responds in accordance with predictions based on a saturating exponential increase during wake and an exponential decline in sleep of homeostatic sleep pressure during both chronic sleep restriction and extension.


Assuntos
Adaptação Fisiológica/fisiologia , Ondas Encefálicas/fisiologia , Homeostase , Privação do Sono/fisiopatologia , Sono REM/fisiologia , Adulto , Estudos Cross-Over , Eletroencefalografia , Feminino , Voluntários Saudáveis , Humanos , Masculino , Polissonografia , Sono/fisiologia
4.
J Psychopharmacol ; 29(7): 764-76, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25922426

RESUMO

Current pharmacological treatments for insomnia include benzodiazepine and non-benzodiazepine hypnotics targeting γ-aminobutyric acid (GABA)A receptors, as well as agonists of the melatonin receptors MT1 and MT2. Melatonin, temazepam and zolpidem are thought to exert their effect through different mechanisms of action, but whether this leads to differential effects on electroencephalogram (EEG) power spectra during sleep in middle-aged people is currently not known. To establish whether the effects of prolonged-release melatonin (2 mg) on the nocturnal sleep EEG are different to those of temazepam (20 mg) and zolpidem (10 mg). Sixteen healthy men and women aged 55-64 years participated in a double-blind, placebo-controlled, four-way cross-over trial. Nocturnal sleep was assessed with polysomnography and spectral analysis of the EEG. The effects of single oral doses of prolonged-release melatonin, temazepam and zolpidem on EEG slow-wave activity (SWA, 0.75-4.5 Hz) and other frequencies during nocturnal non-rapid eye movement (NREM) sleep were compared. In an entire night analysis prolonged-release melatonin did not affect SWA, whereas temazepam and zolpidem significantly reduced SWA compared with placebo. Temazepam significantly reduced SWA compared with prolonged-release melatonin. Prolonged-release melatonin only reduced SWA during the first third of the night compared with placebo. These data show that the effects of prolonged-release melatonin on the nocturnal sleep EEG are minor and are different from those of temazepam and zolpidem; this is likely due to the different mechanisms of action of the medications.


Assuntos
Melatonina/farmacologia , Piridinas/farmacologia , Sono/efeitos dos fármacos , Temazepam/farmacologia , Estudos Cross-Over , Preparações de Ação Retardada , Método Duplo-Cego , Eletroencefalografia , Feminino , Moduladores GABAérgicos/administração & dosagem , Moduladores GABAérgicos/farmacologia , Humanos , Hipnóticos e Sedativos/administração & dosagem , Hipnóticos e Sedativos/farmacologia , Masculino , Melatonina/administração & dosagem , Pessoa de Meia-Idade , Polissonografia , Piridinas/administração & dosagem , Temazepam/administração & dosagem , Zolpidem
5.
IEEE Trans Neural Syst Rehabil Eng ; 23(1): 1-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24951703

RESUMO

A new supervised approach for decomposition of single channel signal mixtures is introduced in this paper. The performance of the traditional singular spectrum analysis algorithm is significantly improved by applying tensor decomposition instead of traditional singular value decomposition. As another contribution to this subspace analysis method, the inherent frequency diversity of the data has been effectively exploited to highlight the subspace of interest. As an important application, sleep electroencephalogram has been analyzed and the stages of sleep for the subjects in normal condition, with sleep restriction, and with sleep extension have been accurately estimated and compared with the results of sleep scoring by clinical experts.


Assuntos
Eletroencefalografia/estatística & dados numéricos , Sono/fisiologia , Adulto , Algoritmos , Automação , Simulação por Computador , Eletroencefalografia/métodos , Feminino , Humanos , Masculino , Processamento de Sinais Assistido por Computador
6.
PLoS One ; 7(9): e45987, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23029352

RESUMO

BACKGROUND: Cognitive performance deteriorates during extended wakefulness and circadian phase misalignment, and some individuals are more affected than others. Whether performance is affected similarly across cognitive domains, or whether cognitive processes involving Executive Functions are more sensitive to sleep and circadian misalignment than Alertness and Sustained Attention, is a matter of debate. METHODOLOGY/PRINCIPAL FINDINGS: We conducted a 2 × 12-day laboratory protocol to characterize the interaction of repeated partial and acute total sleep deprivation and circadian phase on performance across seven cognitive domains in 36 individuals (18 males; mean ± SD of age = 27.6 ± 4.0 years). The sample was stratified for the rs57875989 polymorphism in PER3, which confers cognitive susceptibility to total sleep deprivation. We observed a deterioration of performance during both repeated partial and acute total sleep deprivation. Furthermore, prior partial sleep deprivation led to poorer cognitive performance in a subsequent total sleep deprivation period, but its effect was modulated by circadian phase such that it was virtually absent in the evening wake maintenance zone, and most prominent during early morning hours. A significant effect of PER3 genotype was observed for Subjective Alertness during partial sleep deprivation and on n-back tasks with a high executive load when assessed in the morning hours during total sleep deprivation after partial sleep loss. Overall, however, Subjective Alertness and Sustained Attention were more affected by both partial and total sleep deprivation than other cognitive domains and tasks including n-back tasks of Working Memory, even when implemented with a high executive load. CONCLUSIONS/SIGNIFICANCE: Sleep loss has a primary effect on Sleepiness and Sustained Attention with much smaller effects on challenging Working Memory tasks. These findings have implications for understanding how sleep debt and circadian rhythmicity interact to determine waking performance across cognitive domains and individuals.


Assuntos
Ritmo Circadiano , Desempenho Psicomotor , Privação do Sono/complicações , Adulto , Cognição , Função Executiva , Feminino , Humanos , Masculino , Memória de Curto Prazo , Proteínas Circadianas Period/genética , Polimorfismo de Nucleotídeo Único , Privação do Sono/genética , Adulto Jovem
7.
J Psychopharmacol ; 26(8): 1047-57, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21940760

RESUMO

AMPA receptor modulation is a potential novel approach to enhance cognitive performance. CX717 is a positive allosteric modulator of the AMPA receptor that has shown efficacy in rodent and primate cognition models. CX717 (100 mg, 300 mg and 1000 mg) and placebo were studied in 16 healthy male volunteers (18-45 years) in a randomized, crossover study. Cognitive function, arousal and recovery sleep (by polysomnography) were assessed during the extended wakefulness protocol. Placebo condition was associated with significant decrements in cognition, particularly at the circadian nadir (between 03:00 and 05:00). Pre-specified primary and secondary analyses (general linear mixed modelling, GLMM) at each separate time point did not reveal consistent improvements in performance or objective alertness with any dose of CX717. Exploratory repeated measures analysis, a method used to take into account the influence of individual differences, demonstrated an improvement in attention-based task performance following the 1000 mg dose. Analysis of the recovery sleep showed that CX717 1000 mg significantly reduced stage 4 and slow-wave sleep (p ≤ 0.05) with evidence of reduced electroencephalogram (EEG) slow-wave and spindle activity. The study suggests that CX717 only at the 1000 mg dose may counteract effects of sleep deprivation on attention-based tasks and that it may interfere with subsequent recovery sleep.


Assuntos
Nível de Alerta/efeitos dos fármacos , Transtornos Cognitivos/tratamento farmacológico , Isoxazóis/uso terapêutico , Desempenho Psicomotor/efeitos dos fármacos , Privação do Sono/tratamento farmacológico , Sono/efeitos dos fármacos , Vigília/efeitos dos fármacos , Adolescente , Adulto , Regulação Alostérica/efeitos dos fármacos , Ondas Encefálicas/efeitos dos fármacos , Ondas Encefálicas/fisiologia , Transtornos Cognitivos/complicações , Transtornos Cognitivos/fisiopatologia , Estudos Cross-Over , Relação Dose-Resposta a Droga , Eletroencefalografia/efeitos dos fármacos , Eletroencefalografia/métodos , Eletroencefalografia/psicologia , Humanos , Isoxazóis/efeitos adversos , Masculino , Pessoa de Meia-Idade , Nootrópicos/efeitos adversos , Nootrópicos/uso terapêutico , Polissonografia/efeitos dos fármacos , Polissonografia/métodos , Desempenho Psicomotor/fisiologia , Receptores de AMPA/agonistas , Sono/fisiologia , Privação do Sono/complicações , Privação do Sono/fisiopatologia , Vigília/fisiologia
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