Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
J Clin Neurophysiol ; 40(6): 507-515, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36930208

RESUMO

SUMMARY: In this review, authors discuss epilepsy originating from posterior cingulate regions, a challenging entity to diagnose and most likely underrecognized. A systematic review of posterior middle and posterior cingulate epilepsy cases was conducted to present a summary of current knowledge about this localization-based type of epilepsy. The literature search identified 32 articles, for a total of 69 patients (34 with posterior middle cingulate epilepsy [pMCE] and 35 with posterior cingulate epilepsy [PCE]). Most patients were children and young adults with drug-resistant lesional epilepsy with high seizure burden. In both groups, most patients reported auras, mainly sensory, but various types were reported, including autonomic, behavioral, and cognitive manifestations. Most pMCE and PCE showed motor manifestations (mainly respectively asymmetric tonic posturing and automotor features). Impaired awareness during seizures was more frequently reported in PCE than in pMCE. As for ictal scalp EEG, epileptogenic abnormalities were poorly lateralized and did not localize the seizure onset zone. An ictal temporal involvement was only observed in PCE. Interictal EEG findings were nonspecific. As for other presurgical noninvasive investigations, data are limited, and no studies have adequately assessed their value. Partly explained by our inclusion criteria, most patients underwent a surgical procedure (either lesionectomy or resection of epileptogenic zone as defined by intracranial EEG study results), which overall yielded good outcomes.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia do Lobo Frontal , Criança , Adulto Jovem , Humanos , Epilepsia do Lobo Frontal/diagnóstico , Giro do Cíngulo , Convulsões/diagnóstico , Eletroencefalografia/métodos , Eletrocorticografia , Epilepsia Resistente a Medicamentos/diagnóstico , Epilepsia Resistente a Medicamentos/cirurgia
2.
Epileptic Disord ; 24(3): 561-566, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35770780

RESUMO

OBJECTIVE: Déjà-vu is a mental phenomenon commonly experienced during temporal lobe seizures and can be evoked by electrical stimulation of the temporal lobe. We analyzed reproducible déjà-vu experiences evoked by stimulating the insula in two patients with pharmacoresistant temporal lobe epilepsy. METHODS: We reviewed video-electroencephalography (EEG) recordings from extraoperative electrical cortical stimulation sessions. In addition, we performed the directed transfer function (DTF) effective connectivity measure of monopolar signals in Patient 1. To highlight elective changes due to each stimulation, we subtracted pre-stimulation DTF matrices from early poststimulation matrices. This analysis was performed for both non-inducing-déjàvu stimulation (control matrix) and déjà-vu-inducing stimulation (active matrix). Finally, the control matrix was subtracted from the active matrix. RESULTS: Comparison of effective connectivity during control stimulation versus déjà-vu-inducing stimulation revealed a reversal of connectivity levels in three main regions: the contralateral inferior insula (the ipsilateral insula could not be analyzed), bilateral mesiotemporal regions and the ipsilateral superior frontal gyrus. The drivers of evoked déjà-vu were the mesiotemporal regions (mainly ipsilateral) and the ipsilateral superior frontal gyrus. SIGNIFICANCE: Although our findings are possibly anecdotal, the insula may (in rare instances) remotely generate unexpected déjà-vu. If confirmed by further studies, this might change the assessment strategy for possible causes of anterior temporal lobectomy failure.


Assuntos
Déjà Vu , Epilepsia do Lobo Temporal , Estimulação Elétrica , Eletroencefalografia , Epilepsia do Lobo Temporal/terapia , Humanos , Lobo Temporal
3.
IEEE Trans Radiat Plasma Med Sci ; 6(4): 393-403, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35372739

RESUMO

The best crystal identification (CI) algorithms proposed so far for phoswich detectors are based on adaptive filtering and pulse shape discrimination (PSD). However, these techniques require free running analog to digital converters, which is no longer possible with the ever increasing pixelization of new detectors. We propose to explore the dual-threshold time-over-threshold (ToT) technique, used to measure events energy and time of occurence, as a more robust solution for crystal identification with broad energy windows in phoswich detectors. In this study, phoswich assemblies made of various combinations of LGSO and LYSO scintillators with decay times in the range 30 to 65 ns were investigated for the LabPET II detection front-end. The electronic readout is based on a 4 × 8 APD array where pixels are individually coupled to charge sensitive preamplifiers followed by first order CR-RC shapers with 75 ns peaking time. Crystal identification data were sorted out based on the measurements of likeliness between acquired signals and a time domain model of the analog front-end. Results demonstrate that crystal identification can be successfully performed using a dual-threshold ToT scheme with a discrimination accuracy of 99.1% for LGSO (30 ns)/LGSO (45 ns), 98.1% for LGSO (65 ns)/LYSO (40 ns) and 92.1% for LYSO (32 ns)/LYSO (47 ns), for an energy window of [350-650] keV. Moreover, the method shows a discrimination accuracy >97% for the two first pairs and ~90% for the last one when using a wide energy window of [250-650] keV.

4.
Epileptic Disord ; 24(3): 561-566, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37401785

RESUMO

OBJECTIVE: Déjà-vu is a mental phenomenon commonly experienced during temporal lobe seizures and can be evoked by electrical stimulation of the temporal lobe. We analyzed reproducible déjà-vu experiences evoked by stimulating the insula in two patients with pharmacoresistant temporal lobe epilepsy. METHODS: We reviewed video-electroencephalography (EEG) recordings from extraoperative electrical cortical stimulation sessions. In addition, we performed the directed transfer function (DTF) effective connectivity measure of monopolar signals in Patient 1. To highlight elective changes due to each stimulation, we subtracted pre-stimulation DTF matrices from early poststimulation matrices. This analysis was performed for both non-inducing-déjàvu stimulation (control matrix) and déjà-vu-inducing stimulation (active matrix). Finally, the control matrix was subtracted from the active matrix. RESULTS: Comparison of effective connectivity during control stimulation versus déjà-vu-inducing stimulation revealed a reversal of connectivity levels in three main regions: the contralateral inferior insula (the ipsilateral insula could not be analyzed), bilateral mesiotemporal regions and the ipsilateral superior frontal gyrus. The drivers of evoked déjà-vu were the mesiotemporal regions (mainly ipsilateral) and the ipsilateral superior frontal gyrus. SIGNIFICANCE: Although our findings are possibly anecdotal, the insula may (in rare instances) remotely generate unexpected déjà-vu. If confirmed by further studies, this might change the assessment strategy for possible causes of anterior temporal lobectomy failure.


Assuntos
Déjà Vu , Epilepsia do Lobo Temporal , Humanos , Lobo Temporal , Epilepsia do Lobo Temporal/terapia , Eletroencefalografia , Estimulação Elétrica
5.
Phys Med Biol ; 66(6): 065019, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33412542

RESUMO

The LabPET II is a new positron emission tomography technology platform designed to achieve submillimetric spatial resolution imaging using fully pixelated avalanche photodiodes-based detectors and highly integrated parallel front-end processing electronics. The detector was designed as a generic building block to develop devices for preclinical imaging of small to mid-sized animals and for clinical imaging of the human brain. The aim of this work is to assess the physical characteristics and imaging performance of the mouse version of LabPET II scanner following the NEMA NU4-2008 standard and using high resolution phantoms and in vivo imaging applications. A reconstructed spatial resolution of 0.78 mm (0.5 µ l) is measured close to the center of the radial field of view. With an energy window of 350 650 keV, the system absolute sensitivity is 1.2% and its maximum noise equivalent count rate reaches 61.1 kcps at 117 MBq. Submillimetric spatial resolution is achieved in a hot spot phantom and tiny bone structures were resolved with unprecedented contrast in the mouse. These results provide convincing evidence of the capabilities of the LabPET II technology for biomolecular imaging in preclinical research.


Assuntos
Imagens de Fantasmas , Tomografia por Emissão de Pósitrons/métodos , Animais , Encéfalo , Calibragem , Eletrônica , Desenho de Equipamento , Fluordesoxiglucose F18 , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Camundongos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Imagem Corporal Total/métodos
6.
J Nurs Care Qual ; 35(3): 270-275, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32433152

RESUMO

BACKGROUND: The use of chemical restraints (CRs) in health care facilities is a complex intervention that raises questions about its effectiveness and whether it is safe and patient oriented. PURPOSE: This review aims to gather nursing quality standards for the use of CR through an innovative method of knowledge synthesis, the realist review, to support the development of a quality evaluation tool. METHODS: A realist review method was chosen. RESULTS: An operational definition of chemical restraint is proposed, a concept seen as synonymous with the management of behavioral symptoms by pharmacological agents with sedative proprieties. Twenty-eight quality standards were identified and presented in a theoretical model. CONCLUSIONS: These quality standards will allow the evaluation of practices from a nursing perspective for the use of CR in health care settings.


Assuntos
Hipnóticos e Sedativos , Cuidados de Enfermagem/normas , Comportamento Problema/psicologia , Qualidade da Assistência à Saúde , Humanos , Hipnóticos e Sedativos/efeitos adversos , Hipnóticos e Sedativos/uso terapêutico
7.
Syst Rev ; 8(1): 305, 2019 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-31806051

RESUMO

BACKGROUND: Practitioner-level implementation interventions such as audit and feedback, communities of practice, and local opinion leaders have shown potential to change nurses' behaviour in clinical practice and improve patients' health. However, their effectiveness remains unclear. Moreover, we have a paucity of data regarding the use of theory in implementation studies with nurses, the causal processes-i.e. mechanisms of action-targeted by interventions to change nurses' behaviour in clinical practice, and the constituent components-i.e. behaviour change techniques-included in interventions. Thus, our objectives are threefold: (1) to examine the effectiveness of practitioner-level implementation interventions in changing nurses' behaviour in clinical practice; (2) to identify, in included studies, the type and degree of theory use, the mechanisms of action targeted by interventions and the behaviour change techniques constituting interventions and (3) to examine whether intervention effectiveness is associated with the use of theory or with specific mechanisms of action and behaviour change techniques. METHODS: We will conduct a systematic review based on the Cochrane Effective Practice and Organization of Care (EPOC) Group guidelines. We will search six databases (CINAHL, EMBASE, ERIC, PsycINFO, PubMed and Web of Science) with no time limitation for experimental and quasi-experimental studies that evaluated practitioner-level implementation interventions aiming to change nurses' behaviour in clinical practice. We will also hand-search reference lists of included studies. We will perform screening, full-text review, risk of bias assessment, and data extraction independently with the Covidence systematic review software. We will assess the quality of evidence using the GRADEpro software. We will code included studies independently for theory use (Theory Coding Scheme), mechanisms of action (coding guidelines from Michie) and behaviour change techniques (Behaviour Change Technique Taxonomy v1) with QSR International's NVivo qualitative data analysis software. Meta-analyses will be performed using the Review Manager (RevMan) software. Meta-regression analyses will be performed with IBM SPSS Statistics software. DISCUSSION: This review will inform knowledge users and researchers interested in designing, developing and evaluating implementation interventions to support nurses' behaviour change in clinical practice. Results will provide key insights regarding which causal processes-i.e. mechanisms of action-should be targeted by these interventions, and which constituent components-i.e. behaviour change techniques-should be included in these interventions to increase their effectiveness. SYSTEMATIC REVIEW REGISTRATION: The protocol has been registered at the International Prospective Register of Systematic Reviews (PROSPERO; registration number: CRD42019130446).


Assuntos
Comportamento , Metanálise como Assunto , Processo de Enfermagem , Enfermagem/normas , Projetos de Pesquisa , Revisões Sistemáticas como Assunto
8.
Am J Nurs ; 119(11): 32-40, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31651497

RESUMO

Gestational hypertension, preeclampsia, and peripartum cardiomyopathy are among the most common and often severe pregnancy-specific cardiovascular diseases (CVDs) and causes of complications in pregnancy. This clinical review provides nurses with an overview of pregnancy-specific CVDs, outlines their pathophysiology, and discusses risk factors and assessment. It describes management interventions according to timing: the antepartum, intrapartum, and postpartum phases are each addressed.


Assuntos
Cardiomiopatias/fisiopatologia , Hipertensão Induzida pela Gravidez/fisiopatologia , Pré-Eclâmpsia/fisiopatologia , Complicações Cardiovasculares na Gravidez , Feminino , Humanos , Gravidez , Complicações Cardiovasculares na Gravidez/fisiopatologia , Fatores de Risco
9.
Phys Med Biol ; 62(2): 669-683, 2017 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-28050968

RESUMO

Individually coupled scintillation detectors used in positron emission tomography (PET) imaging suffer from important signal losses due to the suboptimal light collection from crystals. As only a fraction of the light is generally extracted from long and thin scintillators, it is important to identify and understand the predominant causes of signal loss in order to eventually recover it. This simulation study investigates the multiple factors affecting the light transport in high-aspect ratio LYSO scintillators wrapped in specular reflectors through a full factorial design. By exploring various combinations of crystal geometry, readout conditions and wrapping conditions, it was found that an optimum light output can only be achieved through a careful selection of highly reflective material along with high-transmittance optical adhesive used to bond the reflector. Decreasing the adhesive thickness was also found to have a positive outcome in most explored configurations, however to a much lesser extent. Suboptimal reflectivity and adhesive transmittance also lead to an asymmetric light output distribution dependent on the depth of interaction of the radiation, potentially degrading energy resolution. By identifying the factors causing the most significant scintillation light losses through a factorial design, the most promising detector configurations have been identified in the quest for optimal light collection from scintillators.


Assuntos
Luz , Método de Monte Carlo , Tomografia por Emissão de Pósitrons/instrumentação , Contagem de Cintilação/instrumentação , Humanos , Tomografia por Emissão de Pósitrons/métodos , Contagem de Cintilação/métodos
11.
Phys Rev Lett ; 94(6): 066402, 2005 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-15783758

RESUMO

We establish an effective theory for heavy-fermion compounds close to a zero temperature antiferromagnetic (AFM) transition. Coming from the heavy Fermi liquid phase across to the AFM phase, the heavy electron fractionalizes into a light electron, a bosonic spinon, and a new excitation: a spinless fermionic field. Assuming this field acquires dynamics and dispersion when one integrates out the high energy degrees of freedom, we give a scenario for the volume of its Fermi surface through the phase diagram. We apply our theory to the special case of YbRh2(Si1-xGex)2 where we recover, within experimental resolution, several low temperature exponents for transport and thermodynamics.

12.
Phys Rev Lett ; 92(14): 147003, 2004 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-15089567

RESUMO

We study the stability of the quantum-critical point for itinerant ferromagnets commonly described by the Hertz-Millis-Moriya (HMM) theory. We argue that in D

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...