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1.
Sensors (Basel) ; 23(12)2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37420687

RESUMO

Despite several existing techniques for distributed sensing (temperature and strain) using standard Single-Mode optical Fiber (SMF), compensating or decoupling both effects is mandatory for many applications. Currently, most decoupling techniques require special optical fibers and are difficult to implement with high-spatial-resolution distributed techniques, such as OFDR. Therefore, this work's objective is to study the feasibility of decoupling temperature and strain out of the readouts of a phase and polarization analyzer OFDR (ϕ-PA-OFDR) taken over an SMF. For this purpose, the readouts will be subjected to a study using several machine learning algorithms, among them Deep Neural Networks. The motivation that underlies this target is the current blockage in the widespread use of Fiber Optic Sensors in situations where both strain and temperature change, due to the coupled dependence of currently developed sensing methods. Instead of using other types of sensors or even other interrogation methods, the objective of this work is to analyze the available information in order to develop a sensing method capable of providing information about strain and temperature simultaneously.


Assuntos
Algoritmos , Redes Neurais de Computação , Estudos de Viabilidade , Temperatura , Tecnologia de Fibra Óptica
2.
Neuropsychopharmacology ; 48(5): 816-820, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36564531

RESUMO

In preclinical models of alcohol use disorder, the corticotropin-releasing factor (CRF) receptor is upregulated, particularly in the extended amygdala. This upregulation is thought to play a role in stress-induced relapse to drinking by a mechanism that is independent of the hypothalamic-pituitary-adrenal axis. As part of a double-blind, placebo-controlled clinical study with pexacerfont, a selective, orally available, and brain-penetrant CRF1 receptor antagonist which has anti-anxiety effects in preclinical studies, we examined the effect of pexacerfont on the neural response to a social stress task adapted to fMRI. Subjects were 39 individuals (4 women) with high trait anxiety and moderate to severe alcohol use disorder randomized to receive pexacerfont or placebo. The task involved feedback of videoclips of an individual performing the Trier Social Stress Test. Pexacerfont had no effect on the neural response to self-observation under stress. The neural response to viewing oneself under stress vs an unknown other under stress activated prefrontal brain regions including insula, inferior frontal gyrus as well as medial, superior frontal gyri. These regions of activation overlap with those found in studies using similar paradigms. Potential applications of this task to probe neurocircuitry that is disrupted in addiction is discussed.


Assuntos
Alcoolismo , Feminino , Humanos , Alcoolismo/diagnóstico por imagem , Alcoolismo/tratamento farmacológico , Hormônio Liberador da Corticotropina/metabolismo , Retroalimentação , Sistema Hipotálamo-Hipofisário/metabolismo , Sistema Hipófise-Suprarrenal/metabolismo , Testes Psicológicos , Receptores de Hormônio Liberador da Corticotropina , Masculino
3.
Cir. plást. ibero-latinoam ; 48(2): 159-170, abr. - jun. 2022. ilus, tab
Artigo em Espanhol | IBECS (Espanha) | ID: ibc-208939

RESUMO

Introducción y objetivo: Con la evolución de la experiencia en el uso de la toxina botulínica tipo A para tratamientos estéticos se necesitan guías actualizadas de buenas prácticas clínicas. El objetivo de este trabajo fue desarrollar recomendaciones actualizadas para buenas prácticas en el uso clínico diario, con el fin de optimizar el manejo del paciente estético y los resultados obtenidos con la toxina botulínica tipo A. Material y método: Un panel de 44 participantes con amplia experiencia en el uso de la toxina Abobotulinum se reunió para revisar y discutir la evidencia disponible y la práctica clínica en la aplicación estética de la toxina Abobotulinum A. Resultados: Los temas discutidos para la creación de este consenso incluyeron cuestiones directamente relacionadas con el uso y las propiedades de la toxina botulínica tipo A (Azzalure®) y temas generales relativos a la práctica clínica: precisión y campo de efecto de la toxina botulínica tipo A, duración del efecto, rapidez en el inicio de acción, protocolos de tratamiento, tratamientos combinados de toxina botulínica tipo A y ácido hialurónico para mayor satisfacción del paciente y armonía facial, recomendaciones post-tratamiento, diagnóstico y valoración previa del paciente para un efecto óptimo, edad en la que los pacientes comienzan a ser tratados con la toxina y su recomendación como tratamiento preventivo según las escalas de envejecimiento Glogau I o II, manejo de las expectativas del paciente y valoración de la satisfacción del mismo. Conclusiones: Este consenso ha recogido las opiniones, consejos y experiencia de médicos estéticos con amplia experiencia en el uso de la toxina botulínica tipo A para ayudar a los profesionales a conseguir los mejores resultados posibles en términos de eficacia y satisfacción del paciente. (AU)


Background and objective: With the evolution of the experience in the use of botulinum toxin type A for aesthetic treatments, updated guidelines of good clinical practices are needed. The objective of this work was to develop updated recommendations for good practices in daily clinical use, in order to optimize the mana- gement of the aesthetic patient and the results obtained with botulinum toxin type A. Methods: A panel of 44 participants with extensive experience in the use of Abobotulinum toxin met to review and discuss the available evidence and clinical practice in the aesthetic application of Abobotulinum toxin A. Results: The topics discussed for the creation of this consensus included questions directly related to the use and properties of botulinum toxin type A (Azzalure®) and general topics related to clinical practice: precision and field of effect of botulinum toxin type A, duration of effect, speed of onset of action, treatment protocols, combined treatments of botulinum toxin type A and hyaluronic acid for greater patient satisfaction and facial harmony, post-treatment recommendations, diagnosis and prior assessment of the patient for optimal effect, age at which patients begin to be treated with the toxin and its recommendation as a preventive treatment according to the Glogau I or II aging scales, management of patient expectations and assessment of patient satisfaction. Conclusions: This consensus has collected the opinions, advice and experience of aesthetic doctors with extensive experience in the use of botulinum toxin type A to help professionals achieve the best possible results in terms of efficacy and patient satisfaction. (AU)


Assuntos
Humanos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Envelhecimento , Cirurgia Plástica , Toxinas Botulínicas Tipo A , Face , Espanha , Portugal , Consenso
4.
Comput Methods Programs Biomed ; 82(1): 10-9, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16530880

RESUMO

A linear time invariant model is applied to functional fMRI blood flow data. Based on traditional time series analysis, this model assumes that the fMRI stochastic output sequence can be determined by a constant plus a linear filter (hemodynamic response function) of several fixed deterministic inputs and an error term assumed stationary with zero mean. The input function consists of multiple exponential distributed (time delay between images) visual stimuli consisting of negative and erotic images. No a priori assumptions are made about the hemodynamic response function that, in essence, is calculated at each spatial position from the data. The sampling rate for the experiment is 400 ms in order to allow for filtering out higher frequencies associated with the cardiac rate. Since the statistical analysis is carried out in the Fourier domain, temporal correlation problems associated with inference in the time domain are avoided. This formal model easily lends itself to further development based on previously developed statistical techniques.


Assuntos
Algoritmos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Adulto , Encéfalo , Humanos , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , Modelos Lineares , Imageamento por Ressonância Magnética/métodos , Masculino , Distribuição de Poisson , Estados Unidos
5.
Neuropsychopharmacology ; 40(5): 1053-63, 2015 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-25409596

RESUMO

Extensive preclinical data implicate corticotropin-releasing hormone (CRH), acting through its CRH1 receptor, in stress- and dependence-induced alcohol seeking. We evaluated pexacerfont, an orally available, brain penetrant CRH1 antagonist for its ability to suppress stress-induced alcohol craving and brain responses in treatment seeking alcohol-dependent patients in early abstinence. Fifty-four anxious alcohol-dependent participants were admitted to an inpatient unit at the NIH Clinical Center, completed withdrawal treatment, and were enrolled in a double-blind, randomized, placebo-controlled study with pexacerfont (300 mg/day for 7 days, followed by 100 mg/day for 23 days). After reaching steady state, participants were assessed for alcohol craving in response to stressful or alcohol-related cues, neuroendocrine responses to these stimuli, and functional magnetic resonance imaging (fMRI) responses to alcohol-related stimuli or stimuli with positive or negative emotional valence. A separate group of 10 patients received open-label pexacerfont following the same dosing regimen and had cerebrospinal fluid sampled to estimate central nervous system exposure. Pexacerfont treatment had no effect on alcohol craving, emotional responses, or anxiety. There was no effect of pexacerfont on neural responses to alcohol-related or affective stimuli. These results were obtained despite drug levels in cerebrospinal fluid (CSF) that predict close to 90% central CRH1 receptor occupancy. CRH1 antagonists have been grouped based on their receptor dissociation kinetics, with pexacerfont falling in a category characterized by fast dissociation. Our results may indicate that antagonists with slow offset are required for therapeutic efficacy. Alternatively, the extensive preclinical data on CRH1 antagonism as a mechanism to suppress alcohol seeking may not translate to humans.


Assuntos
Dissuasores de Álcool/administração & dosagem , Alcoolismo/tratamento farmacológico , Alcoolismo/fisiopatologia , Pirazóis/administração & dosagem , Triazinas/administração & dosagem , Adulto , Idoso , Dissuasores de Álcool/farmacocinética , Alcoolismo/psicologia , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Depressores do Sistema Nervoso Central , Fissura/efeitos dos fármacos , Sinais (Psicologia) , Método Duplo-Cego , Emoções/fisiologia , Etanol , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Pirazóis/farmacocinética , Receptores de Hormônio Liberador da Corticotropina/antagonistas & inibidores , Estresse Psicológico/tratamento farmacológico , Estresse Psicológico/fisiopatologia , Triazinas/farmacocinética , Percepção Visual/efeitos dos fármacos , Percepção Visual/fisiologia , Adulto Jovem
6.
Comput Math Methods Med ; 2013: 645043, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23840281

RESUMO

A linear time-invariant model based on statistical time series analysis in the Fourier domain for single subjects is further developed and applied to functional MRI (fMRI) blood-oxygen level-dependent (BOLD) multivariate data. This methodology was originally developed to analyze multiple stimulus input evoked response BOLD data. However, to analyze clinical data generated using a repeated measures experimental design, the model has been extended to handle multivariate time series data and demonstrated on control and alcoholic subjects taken from data previously analyzed in the temporal domain. Analysis of BOLD data is typically carried out in the time domain where the data has a high temporal correlation. These analyses generally employ parametric models of the hemodynamic response function (HRF) where prewhitening of the data is attempted using autoregressive (AR) models for the noise. However, this data can be analyzed in the Fourier domain. Here, assumptions made on the noise structure are less restrictive, and hypothesis tests can be constructed based on voxel-specific nonparametric estimates of the hemodynamic transfer function (HRF in the Fourier domain). This is especially important for experimental designs involving multiple states (either stimulus or drug induced) that may alter the form of the response function.


Assuntos
Encéfalo/fisiologia , Modelos Lineares , Imageamento por Ressonância Magnética/estatística & dados numéricos , Modelos Neurológicos , Alcoolismo/sangue , Alcoolismo/fisiopatologia , Biologia Computacional , Potenciais Evocados Visuais , Análise de Fourier , Hemodinâmica , Humanos , Interpretação de Imagem Assistida por Computador , Análise Multivariada , Oxigênio/sangue , Razão Sinal-Ruído , Estatísticas não Paramétricas
10.
ACM arq. catarin. med ; 22(1/2): 45-50, jan.-jun. 1993. ilus
Artigo em Português | LILACS | ID: lil-131523

RESUMO

A despeito do desenvolvimento e disponibilidade da imunoglobulina anti-RH desde 1968, a isoimunizacao materno fetal continua a ser um grave problema de saude, especialmente em comunidades que praticam uma obstetricia precaria. Se as normas de profilaxia fossem universalmente adotadas, a incidencia da doenca poderia ser reduzida em 85 a 90 por cento. O unico tratamento disponivel para as formas severas da doenca hemolitica do feto e recem-nascido continua a ser a transfusao de sangue compativel, RH negativo. No feto com comprometimento leve, a ex-sanguinio transfusao pode ser realizada apos o parto a termo, em um centro de tratamento terciario. Entretanto, um numero expressivo de fetos desenvolvem hidropsia durante a gestacao, antes que a maturidade pulmonar e a possibilidade de vida extra-uterina seja atingida. O desafio passa a ser, entao, a identificacao dos fetos de risco e o encaminhamento para centros capazes de fornecer o tratamento adequado, no caso, a transfusao intra-uterina. Neste relato apresentamos o primeiro caso em que uma ex-sanguinio transfusao intra-uterina atraves da cordocentese foi realizada com sucesso no estado de Santa Catarina.


Assuntos
Humanos , Masculino , Feminino , Gravidez , Recém-Nascido , Transfusão de Sangue Intrauterina , Isoimunização Rh/prevenção & controle , Grupos de Risco , Ultrassonografia Pré-Natal/estatística & dados numéricos
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