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1.
Phys Rev Lett ; 129(20): 201801, 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36461983

RESUMO

This Letter presents the results from the MiniBooNE experiment within a full "3+1" scenario where one sterile neutrino is introduced to the three-active-neutrino picture. In addition to electron-neutrino appearance at short baselines, this scenario also allows for disappearance of the muon-neutrino and electron-neutrino fluxes in the Booster Neutrino Beam, which is shared by the MicroBooNE experiment. We present the 3+1 fit to the MiniBooNE electron-(anti)neutrino and muon-(anti)neutrino data alone and in combination with MicroBooNE electron-neutrino data. The best-fit parameters of the combined fit with the exclusive charged-current quasielastic analysis (inclusive analysis) are Δm^{2}=0.209 eV^{2}(0.033 eV^{2}), |U_{e4}|^{2}=0.016(0.500), |U_{µ4}|^{2}=0.500(0.500), and sin^{2}(2θ_{µe})=0.0316(1.0). Comparing the no-oscillation scenario to the 3+1 model, the data prefer the 3+1 model with a Δχ^{2}/d.o.f.=24.7/3(17.3/3), a 4.3σ(3.4σ) preference assuming the asymptotic approximation given by Wilks's theorem.

2.
Phys Rev Lett ; 129(2): 021801, 2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35867467

RESUMO

We report the first results of a search for leptophobic dark matter (DM) from the Coherent-CAPTAIN-Mills (CCM) liquid argon (LAr) detector. An engineering run with 120 photomultiplier tubes (PMTs) and 17.9×10^{20} protons on target (POT) was performed in fall 2019 to study the characteristics of the CCM detector. The operation of this 10-ton detector was strictly light based with a threshold of 50 keV and used coherent elastic scattering off argon nuclei to detect DM. Despite only 1.5 months of accumulated luminosity, contaminated LAr, and nonoptimized shielding, CCM's first engineering run has already achieved sensitivity to previously unexplored parameter space of light dark matter models with a baryonic vector portal. With an expected background of 115 005 events, we observe 115 005+16.5 events which is compatible with background expectations. For a benchmark mediator-to-DM mass ratio of m_{V_{B}}/m_{χ}=2.1, DM masses within the range 9 MeV≲m_{χ}≲50 MeV are excluded at 90% C. L. in the leptophobic model after applying the Feldman-Cousins test statistic. CCM's upgraded run with 200 PMTs, filtered LAr, improved shielding, and 10 times more POT will be able to exclude the remaining thermal relic density parameter space of this model, as well as probe new parameter space of other leptophobic DM models.

3.
Phys Rev Lett ; 121(22): 221801, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30547637

RESUMO

The MiniBooNE experiment at Fermilab reports results from an analysis of ν_{e} appearance data from 12.84×10^{20} protons on target in neutrino mode, an increase of approximately a factor of 2 over previously reported results. A ν_{e} charged-current quasielastic event excess of 381.2±85.2 events (4.5σ) is observed in the energy range 200

4.
Phys Rev Lett ; 120(14): 141802, 2018 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-29694148

RESUMO

We report the first measurement of monoenergetic muon neutrino charged current interactions. MiniBooNE has isolated 236 MeV muon neutrino events originating from charged kaon decay at rest (K^{+}→µ^{+}ν_{µ}) at the NuMI beamline absorber. These signal ν_{µ}-carbon events are distinguished from primarily pion decay in flight ν_{µ} and ν[over ¯]_{µ} backgrounds produced at the target station and decay pipe using their arrival time and reconstructed muon energy. The significance of the signal observation is at the 3.9σ level. The muon kinetic energy, neutrino-nucleus energy transfer (ω=E_{ν}-E_{µ}), and total cross section for these events are extracted. This result is the first known-energy, weak-interaction-only probe of the nucleus to yield a measurement of ω using neutrinos, a quantity thus far only accessible through electron scattering.

5.
Phys Rev Lett ; 118(22): 221803, 2017 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-28621993

RESUMO

The MiniBooNE-DM Collaboration searched for vector-boson mediated production of dark matter using the Fermilab 8-GeV Booster proton beam in a dedicated run with 1.86×10^{20} protons delivered to a steel beam dump. The MiniBooNE detector, 490 m downstream, is sensitive to dark matter via elastic scattering with nucleons in the detector mineral oil. Analysis methods developed for previous MiniBooNE scattering results were employed, and several constraining data sets were simultaneously analyzed to minimize systematic errors from neutrino flux and interaction rates. No excess of events over background was observed, leading to a 90% confidence limit on the dark matter cross section parameter, Y=ε^{2}α_{D}(m_{χ}/m_{V})^{4}≲10^{-8}, for α_{D}=0.5 and for dark matter masses of 0.01

6.
Ann Oncol ; 27(5): 806-12, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26861603

RESUMO

BACKGROUND: Despite the effectiveness of adjuvant endocrine therapy in preventing breast cancer recurrence, breast cancer events continue at a high rate for at least 10 years after completion of therapy. PATIENTS AND METHODS: This randomised open label phase III trial recruited postmenopausal women from 29 Australian and New Zealand sites, with hormone receptor-positive early breast cancer, who had completed ≥4 years of endocrine therapy [aromatase inhibitor (AI), tamoxifen, ovarian suppression, or sequential combination] ≥1 year prior, to oral letrozole 2.5 mg daily for 5 years, or observation. Treatment allocation was by central computerised randomisation, stratified by institution, axillary node status and prior endocrine therapy. The primary outcome was invasive breast cancer events (new invasive primary, local, regional or distant recurrence, or contralateral breast cancer), analysed by intention to treat. The secondary outcomes were disease-free survival (DFS), overall survival, and safety. RESULTS: Between 16 May 2007 and 14 March 2012, 181 patients were randomised to letrozole and 179 to observation (median age 64.3 years). Endocrine therapy was completed at a median of 2.6 years before randomisation, and 47.5% had tumours of >2 cm and/or node positive. At 3.9 years median follow-up (interquartile range 3.1-4.8), 2 patients assigned letrozole (1.1%) and 17 patients assigned observation (9.5%) had experienced an invasive breast cancer event (difference 8.4%, 95% confidence interval 3.8% to 13.0%, log-rank test P = 0.0004). Twenty-four patients (13.4%) in the observation and 14 (7.7%) in the letrozole arm experienced a DFS event (log-rank P = 0.067). Adverse events linked to oestrogen depletion, but not serious adverse events, were more common with letrozole. CONCLUSION: These results should be considered exploratory, but lend weight to emerging data supporting longer duration endocrine therapy for hormone receptor-positive breast cancer, and offer insight into reintroduction of AI therapy. CLINICAL TRIALS NUMBER: Australian New Zealand Clinical Trials Registry (www.anzctr.org.au), ACTRN12607000137493.


Assuntos
Antineoplásicos Hormonais/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Nitrilas/administração & dosagem , Triazóis/administração & dosagem , Idoso , Inibidores da Aromatase/administração & dosagem , Austrália , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Letrozol , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Pós-Menopausa , Receptores de Estrogênio/genética , Receptores de Progesterona/genética , Tamoxifeno/administração & dosagem , Resultado do Tratamento
7.
Mol Phylogenet Evol ; 99: 168-181, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27026115

RESUMO

The African river frog genus Amietia is found near rivers and other lentic water sources throughout central, eastern, and southern Africa. Because the genus includes multiple morphologically conservative species, taxonomic studies of river frogs have been relatively limited. We sampled 79 individuals of Amietia from multiple localities in and near the Albertine Rift (AR) of Burundi, Democratic Republic of the Congo, and Uganda. We utilized single-gene (16S) and concatenated (12S, 16S, cyt b and RAG1) gene-tree analyses and coalescent species-tree analyses to construct phylogenetic trees. Two divergence dating approaches were used in BEAST, including secondary calibration points with 12S, 16S, cyt b and RAG1, and a molecular clock with the 12S, 16S, and cyt b genes. All analyses recovered Amietia as monophyletic with strong support, and revealed several well-supported cryptic lineages, which is consistent with other recent phylogeography studies of AR amphibians. Dating estimates were similar, and Amietia diversification is coincident with global cooling and aridification events in the Miocene and Pliocene, respectively. Our results suggest additional taxonomic work is needed to describe multiple new species of AR Amietia, some of which have limited geographic distributions that are likely to be of conservation concern.


Assuntos
Anuros/classificação , Evolução Biológica , Animais , Anuros/genética , Biodiversidade , Congo , Citocromos b/genética , Proteínas de Homeodomínio/genética , Filogenia , Filogeografia , RNA Ribossômico/genética , RNA Ribossômico 16S/genética , Rios
8.
Neuroimage ; 99: 461-76, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24830841

RESUMO

Scalp EEG recordings and the classification of interictal epileptiform discharges (IED) in patients with epilepsy provide valuable information about the epileptogenic network, particularly by defining the boundaries of the "irritative zone" (IZ), and hence are helpful during pre-surgical evaluation of patients with severe refractory epilepsies. The current detection and classification of epileptiform signals essentially rely on expert observers. This is a very time-consuming procedure, which also leads to inter-observer variability. Here, we propose a novel approach to automatically classify epileptic activity and show how this method provides critical and reliable information related to the IZ localization beyond the one provided by previous approaches. We applied Wave_clus, an automatic spike sorting algorithm, for the classification of IED visually identified from pre-surgical simultaneous Electroencephalogram-functional Magnetic Resonance Imagining (EEG-fMRI) recordings in 8 patients affected by refractory partial epilepsy candidate for surgery. For each patient, two fMRI analyses were performed: one based on the visual classification and one based on the algorithmic sorting. This novel approach successfully identified a total of 29 IED classes (compared to 26 for visual identification). The general concordance between methods was good, providing a full match of EEG patterns in 2 cases, additional EEG information in 2 other cases and, in general, covering EEG patterns of the same areas as expert classification in 7 of the 8 cases. Most notably, evaluation of the method with EEG-fMRI data analysis showed hemodynamic maps related to the majority of IED classes representing improved performance than the visual IED classification-based analysis (72% versus 50%). Furthermore, the IED-related BOLD changes revealed by using the algorithm were localized within the presumed IZ for a larger number of IED classes (9) in a greater number of patients than the expert classification (7 and 5, respectively). In contrast, in only one case presented the new algorithm resulted in fewer classes and activation areas. We propose that the use of automated spike sorting algorithms to classify IED provides an efficient tool for mapping IED-related fMRI changes and increases the EEG-fMRI clinical value for the pre-surgical assessment of patients with severe epilepsy.


Assuntos
Eletroencefalografia/classificação , Eletroencefalografia/métodos , Epilepsias Parciais/classificação , Imageamento por Ressonância Magnética/métodos , Adulto , Algoritmos , Resistência a Medicamentos , Epilepsias Parciais/patologia , Epilepsias Parciais/fisiopatologia , Epilepsia do Lobo Frontal/classificação , Epilepsia do Lobo Frontal/patologia , Epilepsia do Lobo Frontal/fisiopatologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Oxigênio/sangue , Lobo Parietal/patologia , Lobo Parietal/fisiopatologia , Projetos Piloto , Adulto Jovem
9.
Int J Pediatr Otorhinolaryngol ; 177: 111832, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38215661

RESUMO

BACKGROUND: One third of children require repeat ventilation tube insertion (VTI) for otitis media. Disease recurrence is associated with persistent middle ear bacterial biofilms. With demonstration that Dornase alfa (a DNase) disrupts middle ear effusion biofilms ex vivo, we identified potential for this as an anti-biofilm therapy to prevent repeat VTI. First, safety and tolerability needed to be measured. METHODS: This was a phase 1B double-blinded randomized control trial conducted in Western Australia. Children between 6 months and 5 years undergoing VTI for bilateral middle ear effusion were recruited between 2012 and 2014 and followed for two years. Children's ears were randomized to receive either Dornase alfa (1 mg/mL) or 0.9 % sodium chloride (placebo) at time of surgery. Children were followed up at 2 weeks post-VTI and at 3-monthly intervals for 2 years. Outcomes assessed were: 1) safety and tolerability, 2) otorrhoea frequency, 3) blocked or extruded ventilation tube (VT) frequency, 4) time to blockage or extrusion, 5) time to infection recurrence and/or need for repeat VTI. RESULTS: Sixty children (mean age 2.3 years) were enrolled with 87 % reaching study endpoint. Treatment did not change otorrhoea frequency. Hearing improved in all children following VTI, with no indication of ototoxicity. Dornase alfa had some effect on increasing time until VT extrusion (p = 0.099); and blockage and/or extrusion (p = 0.122). Frequency of recurrence and time until recurrence were similar. Fourteen children required repeat VTI within the follow-up period. CONCLUSION: A single application of Dornase alfa into the middle ear at time of VTI was safe, non-ototoxic, and well-tolerated. TRIAL REGISTRATION: ACTRN12623000504617.


Assuntos
Otopatias , Otite Média com Derrame , Otite Média , Criança , Humanos , Pré-Escolar , Otite Média com Derrame/cirurgia , Otite Média/tratamento farmacológico , Otite Média/cirurgia , Desoxirribonuclease I , Orelha Média , Otopatias/cirurgia , Ventilação da Orelha Média/efeitos adversos , Cloreto de Sódio , Proteínas Recombinantes
10.
Appl Opt ; 52(36): 8747-58, 2013 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-24513939

RESUMO

The increasing scale of cryogenic detector arrays for submillimeter and millimeter wavelength astrophysics has led to the need for large aperture, high index of refraction, low loss, cryogenic refracting optics. Silicon with n=3.4, low loss, and high thermal conductivity is a nearly optimal material for these purposes but requires an antireflection (AR) coating with broad bandwidth, low loss, low reflectance, and a matched coefficient of thermal expansion. We present an AR coating for curved silicon optics comprised of subwavelength features cut into the lens surface with a custom three-axis silicon dicing saw. These features constitute a metamaterial that behaves as a simple dielectric coating. We have fabricated silicon lenses as large as 33.4 cm in diameter with micromachined layers optimized for use between 125 and 165 GHz. Our design reduces average reflections to a few tenths of a percent for angles of incidence up to 30° with low cross polarization. We describe the design, tolerance, manufacture, and measurements of these coatings and present measurements of the optical properties of silicon at millimeter wavelengths at cryogenic and room temperatures. This coating and lens fabrication approach is applicable from centimeter to submillimeter wavelengths and can be used to fabricate coatings with greater than octave bandwidth.

11.
Trials ; 24(1): 202, 2023 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-36934272

RESUMO

BACKGROUND: The need for coronavirus 2019 (COVID-19) vaccination in different age groups and populations is a subject of great uncertainty and an ongoing global debate. Critical knowledge gaps regarding COVID-19 vaccination include the duration of protection offered by different priming and booster vaccination regimens in different populations, including homologous or heterologous schedules; how vaccination impacts key elements of the immune system; how this is modified by prior or subsequent exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and future variants; and how immune responses correlate with protection against infection and disease, including antibodies and effector and T cell central memory. METHODS: The Platform Trial In COVID-19 priming and BOOsting (PICOBOO) is a multi-site, multi-arm, Bayesian, adaptive, randomised controlled platform trial. PICOBOO will expeditiously generate and translate high-quality evidence of the immunogenicity, reactogenicity and cross-protection of different COVID-19 priming and booster vaccination strategies against SARS-CoV-2 and its variants/subvariants, specific to the Australian context. While the platform is designed to be vaccine agnostic, participants will be randomised to one of three vaccines at trial commencement, including Pfizer's Comirnaty, Moderna's Spikevax or Novavax's Nuvaxovid COVID-19 vaccine. The protocol structure specifying PICOBOO is modular and hierarchical. Here, we describe the Core Protocol, which outlines the trial processes applicable to all study participants included in the platform trial. DISCUSSION: PICOBOO is the first adaptive platform trial evaluating different COVID-19 priming and booster vaccination strategies in Australia, and one of the few established internationally, that is designed to generate high-quality evidence to inform immunisation practice and policy. The modular, hierarchical protocol structure is intended to standardise outcomes, endpoints, data collection and other study processes for nested substudies included in the trial platform and to minimise duplication. It is anticipated that this flexible trial structure will enable investigators to respond with agility to new research questions as they arise, such as the utility of new vaccines (such as bivalent, or SARS-CoV-2 variant-specific vaccines) as they become available for use. TRIAL REGISTRATION: Australian and New Zealand Clinical Trials Registry ACTRN12622000238774. Registered on 10 February 2022.


Assuntos
COVID-19 , Vacinas , Humanos , SARS-CoV-2 , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Teorema de Bayes , Austrália , Vacinação , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
Neuroimage ; 61(4): 1383-93, 2012 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-22450296

RESUMO

RATIONALE: To improve the sensitivity and specificity of simultaneous electroencephalography and functional magnetic resonance imaging (EEG-fMRI) it is prudent to devise modelling strategies explaining the residual variance. The purpose of this study is to investigate the potential value of including additional regressors for physiological activities, derived from video-EEG, in the modelling of haemodynamic patterns linked to interictal epileptiform discharges (IEDs) using simultaneously recorded video-EEG-fMRI. METHODS: Ten patients with IED (focal epilepsy: 6, idiopathic generalized epilepsy (IGE):4) were studied. BOLD-sensitive fMRI images were acquired on a 3T MRI scanner. 64-channel EEG was recorded using MR-compatible system. A custom made, dual-video-camera system synchronised with EEG was used to record video simultaneously. IEDs and physiological activities were identified and labelled on video-EEG using Brain Analyzer2. fMRI time-series data were pre-processed and analysed using SPM5 software. Two general linear models (GLM) were created; GLM1: IEDs were convolved with the canonical haemodynamic response function and its derivatives. Realignment parameters and pulse regressors were included in the design matrix as confounds, GLM2: GLM1 and additional regressors identified on video-EEG including: eye blinks, hand or foot movement, chewing and swallowing were also included in the design matrix. SPM [F] maps (p<0.05, corrected for family wise error and p<0.001, uncorrected) were generated for both models. We compared the resulting blood oxygen level dependent (BOLD) maps for cluster size, statistical significance and degree of concordance with the irritative zone. RESULTS: BOLD changes relating to physiological activities were generally seen in expected brain areas. In patients with focal epilepsy, the extent and Z-score of the IED-related global maximum BOLD clusters increased in 4/6 patients and additional IED-related BOLD clusters were observed in 3/6 patients for GLM2. Also, the degree of concordance of IED-related maps with irritative zone improved for one patient for GLM2 and was unchanged for the other cases. In patients with IGE, the size and statistical significance for global maximum and other BOLD clusters increased in 2/4 patients. We conclude that the inclusion of additional regressors, derived from video based information, in the design matrix explains a greater amount of variance and can reveal additional IED-related BOLD clusters which may be part of the epileptic networks.


Assuntos
Piscadela/fisiologia , Deglutição/fisiologia , Eletroencefalografia , Epilepsia/fisiopatologia , Imageamento por Ressonância Magnética , Modelos Neurológicos , Mapeamento Encefálico/métodos , Humanos , Interpretação de Imagem Assistida por Computador , Oxigênio/sangue , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador , Gravação em Vídeo
13.
Occup Med (Lond) ; 62(3): 220-2, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22394679

RESUMO

BACKGROUND: The advent of revalidation has created a need for occupational physicians to be provided with further advice on the preparation of their supporting information. A road show was delivered to the Society of Occupational Medicine (SOM) regional groups to meet the need. The objective of the road show was to improve delegates' confidence in the selection and development of supporting information for appraisal and revalidation by assembling a collection of tools. AIMS: To provide internal evaluation of the effectiveness of the road show. METHODS: The audience voting software Turning Point(®) was used to gather delegates' responses to various questions on their opinion and confidence self-rating. Data were then collated from all iterations. RESULTS: Eighty per cent of delegates became more confident in the selection and development of supporting information for appraisal and revalidation, with the improvement in rating scores being highly significant (P < 0.001). The importance of audit and the use of self-reflective were emphasized. CONCLUSIONS: Internal validation using Turning Point(®) was most useful. This was the first time that the SOM had used a road show format to deliver an educational topic. The road show format was successful, and other similar topics would benefit from a similar delivery.


Assuntos
Competência Clínica/normas , Educação Médica Continuada/normas , Educação/normas , Avaliação de Desempenho Profissional/métodos , Humanos , Auditoria Médica , Medicina do Trabalho , Garantia da Qualidade dos Cuidados de Saúde/métodos
14.
Neuroimage ; 49(4): 3219-29, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19948231

RESUMO

INTRODUCTION: EEG-correlated fMRI (EEG-fMRI) studies can reveal haemodynamic changes associated with Interictal Epileptic Discharges (IED). Methodological improvements are needed to increase sensitivity and specificity for localising the epileptogenic zone. We investigated whether the estimated EEG source activity improved models of the BOLD changes in EEG-fMRI data, compared to conventional << event-related >> designs based solely on the visual identification of IED. METHODS: Ten patients with pharmaco-resistant focal epilepsy underwent EEG-fMRI. EEG Source Imaging (ESI) was performed on intra-fMRI averaged IED to identify the irritative zone. The continuous activity of this estimated IED source (cESI) over the entire recording was used for fMRI analysis (cESI model). The maps of BOLD signal changes explained by cESI were compared to results of the conventional IED-related model. RESULTS: ESI was concordant with non-invasive data in 13/15 different types of IED. The cESI model explained significant additional BOLD variance in regions concordant with video-EEG, structural MRI or, when available, intracranial EEG in 10/15 IED. The cESI model allowed better detection of the BOLD cluster, concordant with intracranial EEG in 4/7 IED, compared to the IED model. In 4 IED types, cESI-related BOLD signal changes were diffuse with a pattern suggestive of contamination of the source signal by artefacts, notably incompletely corrected motion and pulse artefact. In one IED type, there was no significant BOLD change with either model. CONCLUSION: Continuous EEG source imaging can improve the modelling of BOLD changes related to interictal epileptic activity and this may enhance the localisation of the irritative zone.


Assuntos
Mapeamento Encefálico/métodos , Diagnóstico por Computador/métodos , Eletroencefalografia/métodos , Epilepsias Parciais/diagnóstico , Epilepsias Parciais/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/fisiopatologia , Adulto , Algoritmos , Relógios Biológicos , Simulação por Computador , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Neurológicos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
Neuroimage ; 53(1): 196-205, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20570736

RESUMO

BACKGROUND: Simultaneous EEG-fMRI can reveal haemodynamic changes associated with epileptic activity which may contribute to understanding seizure onset and propagation. METHODS: Nine of 83 patients with focal epilepsy undergoing pre-surgical evaluation had seizures during EEG-fMRI and analysed using three approaches, two based on the general linear model (GLM) and one using independent component analysis (ICA): The results were compared with intracranial EEG. RESULTS: The canonical GLM analysis revealed significant BOLD signal changes associated with seizures on EEG in 7/9 patients, concordant with the seizure onset zone in 4/7. The Fourier GLM analysis revealed changes in BOLD signal corresponding with the results of the canonical analysis in two patients. ICA revealed components spatially concordant with the seizure onset zone in all patients (8/9 confirmed by intracranial EEG). CONCLUSION: Ictal EEG-fMRI visualises plausible seizure related haemodynamic changes. The GLM approach to analysing EEG-fMRI data reveals localised BOLD changes concordant with the ictal onset zone when scalp EEG reflects seizure onset. ICA provides additional information when scalp EEG does not accurately reflect seizures and may give insight into ictal haemodynamics.


Assuntos
Circulação Cerebrovascular , Eletroencefalografia/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Consumo de Oxigênio , Oxigênio/sangue , Convulsões/fisiopatologia , Mapeamento Encefálico/métodos , Simulação por Computador , Humanos , Modelos Lineares , Modelos Neurológicos , Análise de Componente Principal , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Ann Surg Oncol ; 17(9): 2303-11, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20358300

RESUMO

BACKGROUND: Percutaneous biliary drainage (PBD) is used to relieve malignant bile duct obstruction (MBO) when endoscopic drainage is not feasible. Little is known about the effects of PBD on the quality of life (QoL) in patients with MBO. The aim of this study was to evaluate changes in QoL and pruritus after PBD and to explore the variables that impact these changes. MATERIALS AND METHODS: Eligible patients reported their QoL and pruritus before and after PBD using the Functional Assessment of Cancer Therapy-Hepatobiliary instrument (FACT-HS) and the Visual Analog Scale for Pruritus (VASP). Instruments were completed preprocedure and at 1 and 4 weeks following PBD. RESULTS: A total of 109 (60 male/49 female) patients enrolled; 102 (94%) had unresectable disease. PBD was technically successful (hepatic ducts cannulated at the conclusion of procedure) in all patients. There were 2 procedure-related deaths. All-cause mortality was 10% (N = 11) at 4 weeks and 28% (N = 31) at 8 weeks post-PBD with a median survival of 4.74 months. The mean FACT-HS scores declined significantly (P < .01) over time (101.3, 94.8, 94.7 at baseline, 1 week, 4 weeks, respectively). The VASP scores showed significant improvement at 1 week with continued improvement at 4 weeks (P < .01). CONCLUSIONS: PBD improves pruritus but not QoL in patients with MBO and advanced malignancy. There is high early mortality in this population.


Assuntos
Colestase/cirurgia , Drenagem , Cuidados Paliativos , Qualidade de Vida , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias dos Ductos Biliares/complicações , Neoplasias dos Ductos Biliares/patologia , Neoplasias dos Ductos Biliares/terapia , Colangiocarcinoma/complicações , Colangiocarcinoma/patologia , Colangiocarcinoma/terapia , Colestase/patologia , Neoplasias Colorretais/complicações , Neoplasias Colorretais/secundário , Neoplasias Colorretais/terapia , Feminino , Seguimentos , Neoplasias da Vesícula Biliar/complicações , Neoplasias da Vesícula Biliar/patologia , Neoplasias da Vesícula Biliar/terapia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/terapia , Estudos Prospectivos , Taxa de Sobrevida , Resultado do Tratamento , Adulto Jovem
17.
Int J Pediatr Otorhinolaryngol ; 130 Suppl 1: 109838, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31879085

RESUMO

OBJECTIVE: To perform a comprehensive review of the literature from July 2015 to June 2019 on the pathogenesis of otitis media. Bacteria, viruses and the role of the microbiome as well as the host response are discussed. Directions for future research are also suggested. DATA SOURCES: PubMed database of the National Library of Medicine. REVIEW METHODS: PubMed was searched for any papers pertaining to OM pathogenesis between July 2015 and June 2019. If in English, abstracts were assessed individually for their relevance and included in the report. Members of the panel drafted the report based on these searches and on new data presented at the 20th International Symposium on Recent Advances in Otitis Media. CONCLUSIONS: The main themes that arose in OM pathogenesis were around the need for symptomatic viral infections to develop disease. Different populations potentially having different mechanisms of pathogenesis. Novel bacterial otopathogens are emerging and need to be monitored. Animal models need to continue to be developed and used to understand disease pathogenesis. IMPLICATIONS FOR PRACTICE: The findings in the pathogenesis panel have several implications for both research and clinical practice. The most urgent areas appear to be to continue monitoring the emergence of novel otopathogens, and the need to develop prevention and preventative therapies that do not rely on antibiotics and protect against the development of the initial OM episode.


Assuntos
Infecções Bacterianas/complicações , Infecções Bacterianas/microbiologia , Microbiota , Otite Média/microbiologia , Viroses/complicações , Animais , Pesquisa Biomédica , Modelos Animais de Doenças , Orelha Média/microbiologia , Humanos , Otite Média/prevenção & controle , Otite Média/virologia
18.
Neuroimage ; 46(3): 834-43, 2009 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-19408351

RESUMO

Simultaneous EEG-fMRI acquisitions in patients with epilepsy often reveal distributed patterns of Blood Oxygen Level Dependant (BOLD) change correlated with epileptiform discharges. We investigated if electrical source imaging (ESI) performed on the interictal epileptiform discharges (IED) acquired during fMRI acquisition could be used to study the dynamics of the networks identified by the BOLD effect, thereby avoiding the limitations of combining results from separate recordings. Nine selected patients (13 IED types identified) with focal epilepsy underwent EEG-fMRI. Statistical analysis was performed using SPM5 to create BOLD maps. ESI was performed on the IED recorded during fMRI acquisition using a realistic head model (SMAC) and a distributed linear inverse solution (LAURA). ESI could not be performed in one case. In 10/12 remaining studies, ESI at IED onset (ESIo) was anatomically close to one BOLD cluster. Interestingly, ESIo was closest to the positive BOLD cluster with maximal statistical significance in only 4/12 cases and closest to negative BOLD responses in 4/12 cases. Very small BOLD clusters could also have clinical relevance in some cases. ESI at later time frame (ESIp) showed propagation to remote sources co-localised with other BOLD clusters in half of cases. In concordant cases, the distance between maxima of ESI and the closest EEG-fMRI cluster was less than 33 mm, in agreement with previous studies. We conclude that simultaneous ESI and EEG-fMRI analysis may be able to distinguish areas of BOLD response related to initiation of IED from propagation areas. This combination provides new opportunities for investigating epileptic networks.


Assuntos
Potenciais de Ação , Diagnóstico por Computador/métodos , Eletroencefalografia/métodos , Epilepsia/diagnóstico , Epilepsia/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/fisiopatologia , Adulto , Mapeamento Encefálico/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pediatria/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
19.
Sex Transm Infect ; 85(2): 139-44, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18927181

RESUMO

OBJECTIVE: To examine the acceptance of repeat population-based voluntary counselling and testing (VCT) for HIV in rural Malawi. METHODS: Behavioural and biomarker data were collected in 2004 and 2006 from approximately 3000 adult respondents. In 2004, oral swab specimens were collected and analysed using ELISA and confirmatory Western blot tests, while finger-prick rapid testing was done in 2006. We used cross-tabulations with chi(2) tests and significance tests of proportions to determine the statistical significance of differences in acceptance of VCT by year, individual characteristics and HIV risk. RESULTS: First, over 90% of respondents in each round accepted the HIV test, despite variations in testing protocols. Second, the percentage of individuals who obtained their test results significantly increased from 67% in 2004, when the results were provided in randomly selected locations several weeks after the specimens were collected, to 98% in 2006 when they were made available immediately within the home. Third, whereas there were significant variations in the sociodemographic and behavioural profiles of those who were successfully contacted for a second HIV test, this was not the case for those who accepted repeat VCT. This suggests that variations in the success of repeat testing might come from contacting the individuals rather than from accepting the test or knowing the results. CONCLUSIONS: Repeat HIV testing at home by trained healthcare workers from outside the local area, and with either saliva or blood, is almost universally acceptable in rural Malawi and, thus, likely to be acceptable in similar contexts.


Assuntos
Aconselhamento/estatística & dados numéricos , Infecções por HIV/diagnóstico , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Serviços de Saúde Rural/estatística & dados numéricos , Programas Voluntários/estatística & dados numéricos , Adolescente , Adulto , Feminino , Infecções por HIV/epidemiologia , Comportamentos Relacionados com a Saúde , Humanos , Malaui/epidemiologia , Masculino , Saúde da População Rural , Infecções Sexualmente Transmissíveis/epidemiologia , Adulto Jovem
20.
J R Army Med Corps ; 154(1): 26-30, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19090383

RESUMO

OBJECTIVES: Failure to keep medical appointments, commonly referred to as 'Did Not Attend' (DNA), is a frequent problem in both primary and secondary health care and leads to a waste of valuable resources. Although the reasons for DNA within the general population are well documented, little is known about this behaviour amongst people serving in the armed forces. In this paper we report the findings of a questionnaire-based study investigating the reasons why military personnel fail to keep hospital appointments. METHOD: A postal questionnaire asking questions about the reasons for not attending the appointment and how they perceived the condition for which treatment had been sought, were sent to 167 military patients known to have missed appointments in either a hospital outpatient department or regional rehabilitation unit. 162 controls, who attended appointments, were also sent a questionnaire asking them about factors leading to their appointment and how they perceived the condition that they attended the appointment for. Illness perception was measured using a previously validated Illness perception Questionnaire (IPQ-R). The controls were matched by rank, gender and corps. RESULTS: The overall response rate was 51.5%, with 46% response in the DNA group and 55% in the controls. A previous history of hospital DNA (though not DNA in primary care) and attempting to change the appointment date were associated with DNA (p = 0.01). Those who received a reminder about the appointment were less likely to DNA (p < or = 0.001). Although patients who perceived their condition to be less important were more likely to fail to attend their appointment (p = 0.01), illness perception as measured on the IPQ-R, was not associated with appointment attendance. The most frequent reasons cited for missed appointments were due to administrative problems, with many (38%) respondents being simply unaware that they had an appointment at all or believing that they had cancelled it (14%). Forgetting the appointment (8%) or mixing up the date (21%) were also cited by respondents as reasons for not attending. Only 11% of respondents gave reasons that were specific to a military population, most frequently being on exercise at the time of their appointment. Demographic differences such as age and gender, and practical factors such as appointment day, distance travelled, method of appointment notification, or type of hospital were not found to be associated with attendance. CONCLUSION: The most common reasons for not attending appointments were due to administrative error and an inability amongst patients to recall the correct date of the appointment. Whilst efforts to improve attendance through various reminder systems have been found to be effective in the short term at least, improvements in the efficiency of appointment administration is likely to generate a reduction in DNA and in turn will reduce the wastage of resources.


Assuntos
Agendamento de Consultas , Militares , Cooperação do Paciente , Centros de Reabilitação , Inquéritos e Questionários , Adulto , Estudos de Casos e Controles , Inglaterra , Feminino , Humanos , Masculino , Ambulatório Hospitalar , Encaminhamento e Consulta , Medicina Estatal , Adulto Jovem
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