Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 56
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
BMC Psychiatry ; 24(1): 122, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355533

RESUMO

BACKGROUND: Clozapine is an antipsychotic drug with unique efficacy, and it is the only recommended treatment for treatment-resistant schizophrenia (TRS: failure to respond to at least two different antipsychotics). However, clozapine is also associated with a range of adverse effects which restrict its use, including blood dyscrasias, for which haematological monitoring is required. As treatment resistance is recognised earlier in the illness, the question of whether clozapine should be prescribed in children and young people is increasingly important. However, most research to date has been in older, chronic patients, and evidence regarding the efficacy and safety of clozapine in people under age 25 is lacking. The CLEAR (CLozapine in EARly psychosis) trial will assess whether clozapine is more effective than treatment as usual (TAU), at the level of clinical symptoms, patient rated outcomes, quality of life and cost-effectiveness in people below 25 years of age. Additionally, a nested biomarker study will investigate the mechanisms of action of clozapine compared to TAU. METHODS AND DESIGN: This is the protocol of a multi-centre, open label, blind-rated, randomised controlled effectiveness trial of clozapine vs TAU (any other oral antipsychotic monotherapy licenced in the British National Formulary) for 12 weeks in 260 children and young people with TRS (12-24 years old). AIM AND OBJECTIVES: The primary outcome is the change in blind-rated Positive and Negative Syndrome Scale scores at 12 weeks from baseline. Secondary outcomes include blind-rated Clinical Global Impression, patient-rated outcomes, quality of life, adverse effects, and treatment adherence. Patients will be followed up for 12 months and will be invited to give consent for longer term follow-up using clinical records and potential re-contact for further research. For mechanism of action, change in brain magnetic resonance imaging (MRI) biomarkers and peripheral inflammatory markers will be measured over 12 weeks. DISCUSSION: The CLEAR trial will contribute knowledge on clozapine effectiveness, safety and cost-effectiveness compared to standard antipsychotics in young people with TRS, and the results may guide future clinical treatment recommendation for early psychosis. TRIAL REGISTRATION: ISRCTN Number: 37176025, IRAS Number: 1004947. TRIAL STATUS: In set-up. Protocol version 4.0 01/08/23. Current up to date protocol available here: https://fundingawards.nihr.ac.uk/award/NIHR131175# /.


Assuntos
Antipsicóticos , Clozapina , Transtornos Psicóticos , Esquizofrenia , Criança , Humanos , Adolescente , Idoso , Adulto , Adulto Jovem , Antipsicóticos/efeitos adversos , Clozapina/efeitos adversos , Esquizofrenia Resistente ao Tratamento , Esquizofrenia/terapia , Qualidade de Vida , Transtornos Psicóticos/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
2.
J Radiol Prot ; 41(2)2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33271518

RESUMO

Ground robotic vehicles are often deployed to inspect areas where radioactive floor contamination is a prominent risk. However, the accuracy of detection could be adversely affected by enhanced radiation signal through self-contamination of the robot occurring over the course of the inspection. In this work, it was hypothesised that a six-legged robot could offer advantages over the more conventional ground robotic devices such as wheeled and tracked rovers. To investigate this, experimental contamination testing and computational Monte Carlo simulation techniques (GEANT4) were employed to understand how radioactive contamination pick-up on three different robotic vehicles would affect their detection accuracy. Two robotic vehicles were selected for comparison with the hexapod robot based on their type of locomotion; a wheeled rover and a tracked rover. With the aid of a non-toxic fluorescent tracer dust, the contamination received by the all three vehicles when traversing a contaminated area was initially compared through physical inspection using high definition cameras. The parametric results from these tests where used in the computational study carried out in GEANT4. A cadmium zinc telluride detector was simulated at heights ranging from 10 to 50 cm above each contaminated vehicle, as if it were mounted on a plinth. Assuming a uniform activity of 60 Bq cm-2on all contaminated surfaces, the results suggested that due to the hexapod's small ground-contacting surface area and geometry, radiation detection rates using an uncollimated detector are likely to be overestimated by between only 0.07%-0.12%, compared with 3.95%-8.43% and 1.75%-14.53% for the wheeled and tracked robot alternatives, respectively.


Assuntos
Procedimentos Cirúrgicos Robóticos , Robótica , Simulação por Computador , Método de Monte Carlo
3.
J Acoust Soc Am ; 146(6): 4926, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31893729

RESUMO

Acoustic pulse reflectometry is a method of non-destructive testing used for locating and characterising features and defects in gas-filled objects such as tubes, pipes, and ducts. A sound wave is emitted into the waveguide and travels in the axial direction until it is partially or fully reflected at changes in cross-section. The recorded reflection sequence is analysed to reveal time-of-flight, amplitude, and reflection shape. Analysis of reflection sequences is problematic due to the presence of multiple repeated echoes. The principal contribution is the introduction and demonstration of a method of actively suppressing unwanted echoes by modifying the signal emitted by the speaker in real-time. Unlike previous work, the proposed system accounts for inter-transducer attenuation and does not require re-calibration for each test object. The proposed real-time active absorbing termination is implemented using a programmable embedded controller and shown to function effectively. A quantitative evaluation of available wave separation techniques is provided using a known metric for quantifying the performance of absorbing terminations is introduced.

4.
Psychol Med ; 43(3): 591-602, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22703698

RESUMO

BACKGROUND: Psychotic disorders are highly heritable such that the unaffected relatives of patients may manifest characteristics, or endophenotypes, that are more closely related to risk genes than the overt clinical condition. Facial affect processing is dependent on a distributed cortico-limbic network that is disrupted in psychosis. This study assessed facial affect processing and related brain structure as a candidate endophenotype of first-episode psychosis (FEP). METHOD: Three samples comprising 30 FEP patients, 30 of their first-degree relatives and 31 unrelated healthy controls underwent assessment of facial affect processing and structural magnetic resonance imaging (sMRI) data. Multivariate analysis (partial least squares, PLS) was used to identify a grey matter (GM) system in which anatomical variation was associated with variation in facial affect processing speed. RESULTS: The groups did not differ in their accuracy of facial affect intensity rating but differed significantly in speed of response, with controls responding faster than relatives, who responded faster than patients. Within the control group, variation in speed of affect processing was significantly associated with variation of GM density in amygdala, lateral temporal cortex, frontal cortex and cerebellum. However, this association between cortico-limbic GM density and speed of facial affect processing was absent in patients and their relatives. CONCLUSIONS: Speed of facial affect processing presents as a candidate endophenotype of FEP. The normal association between speed of facial affect processing and cortico-limbic GM variation was disrupted in FEP patients and their relatives.


Assuntos
Encéfalo/patologia , Emoções/fisiologia , Expressão Facial , Transtornos Psicóticos/fisiopatologia , Tempo de Reação/fisiologia , Reconhecimento Psicológico/fisiologia , Adolescente , Adulto , Afeto , Análise de Variância , Encéfalo/fisiopatologia , Mapeamento Encefálico , Estudos de Casos e Controles , Endofenótipos , Feminino , Humanos , Análise dos Mínimos Quadrados , Imageamento por Ressonância Magnética/métodos , Masculino , Estimulação Luminosa , Transtornos Psicóticos/genética , Transtornos Psicóticos/patologia , Tempo de Reação/genética , Adulto Jovem
5.
Psychol Med ; 41(5): 949-58, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21205440

RESUMO

BACKGROUND: Early Intervention in Psychosis Services (EIS) for young people in England experiencing first-episode psychosis (FEP) were commissioned in 2002, based on an expected incidence of 15 cases per 100 000 person-years, as reported by schizophrenia epidemiology in highly urban settings. Unconfirmed reports from EIS thereafter have suggested higher than anticipated rates. The aim of this study was to compare the observed with the expected incidence and delineate the clinical epidemiology of FEP using epidemiologically complete data from the CAMEO EIS, over a 6-year period in Cambridgeshire, for a mixed rural-urban population. METHOD: A population-based study of FEP (ICD-10, F10-39) in people aged 17-35 years referred between 2002 and 2007; the denominator was estimated from mid-year census statistics. Sociodemographic variation was explored by Poisson regression. Crude and directly standardized rates (for age, sex and ethnicity) were compared with pre-EIS rates from two major epidemiological FEP studies conducted in urban English settings. RESULTS: A total of 285 cases met FEP diagnoses in CAMEO, yielding a crude incidence of 50 per 100 000 person-years [95% confidence interval (CI) 44.5-56.2]. Age- and sex-adjusted rates were raised for people from black ethnic groups compared with the white British [incidence rate ratio (IRR) 2.1, 95% CI 1.1-3.8]. Rates in our EIS were comparable with pre-EIS rates observed in more urban areas after age, sex and ethnicity standardization. CONCLUSIONS: Our findings suggest that the incidence observed in EIS is far higher than originally anticipated and is comparable to rates observed in more urban settings prior to the advent of EIS. Sociodemographic variation due to ethnicity and other factors extend beyond urban populations. Our results have implications for psychosis aetiology and service planning.


Assuntos
Planejamento em Saúde Comunitária , Serviços Comunitários de Saúde Mental/estatística & dados numéricos , Transtornos Psicóticos/epidemiologia , Adolescente , Adulto , Área Programática de Saúde , Diagnóstico Precoce , Inglaterra/epidemiologia , Feminino , Pesquisa sobre Serviços de Saúde , Humanos , Incidência , Masculino , Distribuição de Poisson , Análise de Regressão , População Rural , População Urbana
6.
Int J Ment Health Syst ; 15(1): 33, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33853658

RESUMO

BACKGROUND: Psychological safety-speaking up about ideas and concerns, free from interpersonal risk-are essential to the high-risk environment, such as healthcare settings. Psychologically safe working is particularly important in mental health where recovery-oriented approaches rely on collaborative efforts of interprofessional teams to make complex decisions. Much research focuses on antecedents and outcomes associated with psychological safety, but little focus on the practical steps for how to increase psychological safety across and at different levels of a healthcare organisation. AIMS: We explore how a mental health organisation creates an organisation-wide plan for building the foundations of mental health and how to enhance psychological safety. METHODS: This review encompasses strategies across psychological safety and organisational culture change to increase psychological safety at an individual, team and organisational level. We set out a comprehensive overview of the types of strategies and interventions for increasing the ethos of psychological safety and setting the foundations for delivering an organisation-wide programme on this topic. We also provide a list of key targeted areas in mental health that would maximally benefit from increasing psychological safety-both in clinical and non-clinical settings. CONCLUSIONS: Psychological safety is a crucial determinant of safe and effective patient care in mental health services. This paper provides the key steps and considerations, creating a large-scale programme in psychological safety with a focus on mental health and drawing from the current literature, providing concrete steps for how our current understanding of psychological safety into practice.

8.
Transl Psychiatry ; 5: e540, 2015 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-25826115

RESUMO

Psychotic disorders such as schizophrenia are biologically complex and carry huge population morbidity due to their prevalence, persistence and associated disability. Defined by features such as delusions and hallucinations, they involve cognitive dysfunction and neurotransmitter dysregulations that appear mostly to involve the dopaminergic and glutamatergic systems. A number of genetic and environmental factors are associated with these disorders but it has been difficult to identify the biological pathways underlying the principal symptoms. The endophenotype concept of stable, heritable traits that form a mechanistic link between genes and an overt expression of the disorder has potential to reduce the complexity of psychiatric phenotypes. In this study, we used a genetically sensitive design with individuals with a first episode of psychosis, their non-affected first-degree relatives and non-related healthy controls. Metabolomic analysis was combined with neurocognitive assessment to identify multilevel endophenotypic patterns: one concerned reaction times during the performance of cognitive and emotional tests that have previously been associated with the glutamate neurotransmission system, the other involved metabolites involved directly and indirectly in the co-activation of the N-methyl-D-aspartate receptor, a major receptor of the glutamate system. These cognitive and metabolic endophenotypes may comprise a single construct, such that genetically mediated dysfunction in the glutamate system may be responsible for delays in response to cognitive and emotional functions in psychotic disorders. This focus on glutamatergic neurotransmission should guide drug discovery and experimental medicine programmes in schizophrenia and related disorders.


Assuntos
Endofenótipos/sangue , Aminoácidos Excitatórios/sangue , Predisposição Genética para Doença/genética , Transtornos Psicóticos/sangue , Transtornos Psicóticos/genética , Transmissão Sináptica/genética , Adulto , Análise de Variância , Cromatografia Líquida , Feminino , Ácido Glutâmico/sangue , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Espectrometria de Massas , Metabolômica , Testes Neuropsicológicos , Análise de Componente Principal , Transtornos Psicóticos/fisiopatologia , Tempo de Reação , Receptores de N-Metil-D-Aspartato/sangue , Transmissão Sináptica/fisiologia , Adulto Jovem
9.
J Clin Pathol ; 28(2): 99-103, 1975 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1092719

RESUMO

The accuracy of point counting as a histometric technique depends very much on the number of points counted, and the number necessary varies greatly with both the level of accuracy required and the proportion the relevant tissue occupies in the section. It is shown that the number of "hits" is a more useful measure than the total number of points counted, and a simple rule derived for determining the number of hits necessary to achieve any necessary degree of accuracy. A method of progressive estimation of accuracy when attempting to measure the proportion of a tissue that is unevenly distributed is also described. The point-counting graticules commonly used, with 25 points, are inadequate with tissue proportions below 10%. A new graticule design, with 100 points optimally distributed, and usable as a 25-point array if required, is illustrated.


Assuntos
Técnicas Histológicas
10.
Psychiatry Res ; 100(1): 13-20, 2000 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-11090721

RESUMO

We used continuous whole brain functional magnetic resonance imaging (fMRI) with a 3-T magnet to map the cerebral activation associated with auditory hallucinations in four subjects with schizophrenia. The subjects experienced episodes of hallucination whilst in the scanner so that periods of hallucination could be compared with periods of rest in the same individuals. Group analysis demonstrated shared areas of activation in right and left superior temporal gyri, left inferior parietal cortex and left middle frontal gyrus. When the data were examined on an individual basis, the temporal cortex and prefrontal cortex areas were activated during episodes of hallucination in all four subjects. These findings support the theory that auditory hallucination reflects abnormal activation of normal auditory pathways.


Assuntos
Encéfalo/patologia , Dominância Cerebral , Alucinações/etiologia , Imageamento por Ressonância Magnética , Esquizofrenia/complicações , Esquizofrenia/patologia , Adulto , Vias Auditivas , Feminino , Alucinações/patologia , Humanos , Masculino , Modelos Neurológicos , Lobo Parietal/patologia , Córtex Pré-Frontal/patologia , Lobo Temporal/patologia
11.
Vet Rec ; 104(19): 431-3, 1979 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-382606

RESUMO

Data are presented on the size, Leydig cell content and seminiferous tubule dimensions of the normal bull testis. A method of estimating total tubule length, requiring only the measurement of testis volume and the number of tubule cross-sections in a unit area is described, and its applicability to the bull established. The average bull testis contains about 5.2 km of tubules.


Assuntos
Bovinos/anatomia & histologia , Células Intersticiais do Testículo/citologia , Túbulos Seminíferos/anatomia & histologia , Testículo/anatomia & histologia , Animais , Técnicas Histológicas , Masculino
12.
Vet Rec ; 104(22): 500-3, 1979 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-483539

RESUMO

A Friesian bull with bilateral testicular hypoplasia was diagnosed as having a pure 61XXY karyotype. The bull displayed normal sexual behaviour but was azoospermic. At 17 months, the animal's peripheral plasma androgen levels appeared to be lower than normal, and one testicle removed one month later showed small seminiferous tubules totally lacking in germ cells. The Leydig cell volume of this testis was well within the normal range but the tubule length was rather short. At 33 months of age an increase in peripheral plasma androgen levels was noted. In the remaining testis there had been both a considerable rise in Leydig cell volume and a fall in tubule length. These findings may be explained by the interaction of three factors; the effects of the abnormal karyotype, the increased maturity of the animal at 33 months and the reaction of the remaining testis to unilateral castration.


Assuntos
Doenças dos Bovinos/genética , Aberrações dos Cromossomos Sexuais , Testículo/patologia , Androgênios/sangue , Animais , Bovinos , Doenças dos Bovinos/patologia , Doenças dos Bovinos/fisiopatologia , Cariotipagem , Masculino
14.
J Clin Pathol ; 19(2): 203-4, 1966 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16811029
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa