Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 100
Filtrar
1.
AJNR Am J Neuroradiol ; 44(1): 26-32, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36521962

RESUMO

BACKGROUND AND PURPOSE: FLAIR vascular hyperintensities are thought to represent leptomeningeal collaterals in acute ischemic stroke. However, whether all-FLAIR vascular hyperintensities or FLAIR vascular hyperintensities-DWI mismatch, ie, FLAIR vascular hyperintensities beyond the DWI lesion, best reflects collaterals remains debated. We aimed to compare the value of FLAIR vascular hyperintensities-DWI mismatch versus all-FLAIR vascular hyperintensities for collateral assessment using PWI-derived collateral flow maps as a reference. MATERIALS AND METHODS: We retrospectively reviewed the registries of 6 large stroke centers and included all patients with acute stroke with anterior circulation large-vessel occlusion who underwent MR imaging with PWI before thrombectomy. Collateral status was graded from 1 to 4 on PWI-derived collateral flow maps and dichotomized into good (grades 3-4) and poor (grades 1-2). The extent of all-FLAIR vascular hyperintensities and FLAIR vascular hyperintensities-DWI mismatch was assessed on the 7 cortical ASPECTS regions, ranging from 0 (absence) to 7 (extensive), and associations with good collaterals were compared using receiver operating characteristic curves. RESULTS: Of the 209 included patients, 133 (64%) and 76 (36%) had good and poor collaterals, respectively. All-FLAIR vascular hyperintensity extent was similar between collateral groups (P = .76). Conversely, FLAIR vascular hyperintensities-DWI mismatch extent was significantly higher in patients with good compared with poor collaterals (P < .001). The area under the curve was 0.80 (95% CI, 0.74-0.87) for FLAIR vascular hyperintensities-DWI mismatch and 0.52 (95% CI, 0.44-0.60) for all-FLAIR vascular hyperintensities (P < .001 for the comparison), to predict good collaterals. Variables independently associated with good collaterals were smaller DWI lesion volume (P < .001) and larger FLAIR vascular hyperintensities-DWI mismatch (P = .02). CONCLUSIONS: In acute ischemic stroke with large-vessel occlusion, the extent of FLAIR vascular hyperintensities does not reliably reflect collateral status unless one accounts for DWI.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Estudos Retrospectivos , AVC Isquêmico/complicações , Acidente Vascular Cerebral/patologia , Imageamento por Ressonância Magnética , Trombectomia , Isquemia Encefálica/complicações , Imagem de Difusão por Ressonância Magnética/métodos
2.
Infect Dis Now ; 51(7): 622-626, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33870889

RESUMO

INTRODUCTION: Neisseria elongata (NE), a Gram-negative, rod-shaped organism, was previously thought to be non-pathogenic. However, in recent years it has become increasingly recognized as a rare cause of infective endocarditis. In this paper, we report a case of NE infective endocarditis and provide a review of the literature. OBJECTIVES: To describe a case of NE endocarditis, and to review the literature in search of any similar cases of this rare condition. CASE REPORT: Our patient is a 77-year-old, otherwise healthy female patient who was found to have mitral valve endocarditis with valve regurgitation. DISCUSSION: NE endocarditis is a rare condition that typically affects the left cardiac chambers and is associated with high risk of embolization. A literature review retrieved 35 other cases. CONCLUSIONS: Our report underlines the rarity of NE endocarditis, insofar as relatively few cases have been reported. The bacterium presents similarities with HACEK organisms and can potentially cause infective endocarditis.


Assuntos
Endocardite Bacteriana , Endocardite , Doenças das Valvas Cardíacas , Neisseria elongata , Idoso , Endocardite Bacteriana/diagnóstico , Feminino , Humanos
3.
Int J Cardiol ; 330: 259-265, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33592237

RESUMO

BACKGROUND: Friedreich's ataxia (FA) is a rare autosomal recessive mitochondrial disease most commonly due to a triplet repeat expansion guanine-adenine-adenine (GAA) in the FXN gene. Cardiac disease is the major cause of death, patients with reduced left ventricular ejection fraction (LVEF) having the worse prognosis. Longitudinal strain (LS) appeared to be a better predictor of outcome than LVEF in different diseases. We compared the prognostic value of LS measured from the 4 chambers view to LVEF. METHODS: From 2003 to 2017 consecutive patients with FA were included and LS analysis was retrospectively performed. RESULTS: We studied 140 patients, with a median age of 34 (26-41) years (Q1-Q3) with age at onset of 14 (11-19) years and GAA repeats on the shorter allele of 600 (467-783) pb. Mean LS was 19.9 ± 5.0% and LVEF 64 ± 8%. After a mean follow-up of 7.4 ± 3.9 years, 14 patients died. In univariate Cox analysis, all-cause mortality was associated with: LS (HR 0.83; 95%CI, 0.75-0.91, p = 0.0002), LVEF (HR 0.30; 95%CI, 0.19-0.49, p < 0.0001), GAA repeats on the shorter allele (HR 1.29; 95%CI, 1.10-1.51, p = 0.002), age at onset (HR 0.87; 95%CI, 0.77-0.98, p = 0.018), LVSystolic Diameter (HR 1.17; 95%CI, 1.09-1.26, p < 0.0001), LVMass index (HR 1.02; 95%CI, 1.00-1.04, p = 0.027), and LVDiastolic Diameter (HR1.12; 95%CI, 1.01-1.23, p = 0.028). In multivariate analysis, LVEF was the only independent predictor of mortality (HR 0.41; 95%CI, 0.23-0.74, p = 0.0029). CONCLUSION: In FA, LS was not an independent predictor of mortality, LVEF remained the only independent predictor in the present study.


Assuntos
Ataxia de Friedreich , Adulto , Ataxia de Friedreich/diagnóstico , Ataxia de Friedreich/genética , Humanos , Prognóstico , Estudos Retrospectivos , Volume Sistólico , Função Ventricular Esquerda
4.
Eur J Neurol ; 28(1): 124-131, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32896067

RESUMO

BACKGROUND AND PURPOSE: The number of clot retrieval attempts required to achieve complete reperfusion by mechanical thrombectomy impacts functional outcome in acute ischaemic stroke (AIS). Complete reperfusion [expanded Treatment In Cerebral Infarction (eTICI) score = 3] at first pass (FP), is associated with the highest rates of favorable outcome compared to complete reperfusion by multiple passes. The aim of the present study was to investigate the relationship between FP complete reperfusion and infarct growth (IG). METHODS: Anterior AIS patients with baseline and 24-h diffusion-weighted magnetic resonance imaging were included from two prospective registries. IG was measured by voxel-based segmentation of initial and 24-h diffusion-weighted imaging lesions. IG and favorable 3-month modified Rankin Scale (mRS) score (≤ 2) were compared between patients in whom complete reperfusion (eTICI 3) was achieved with a single pass (FP group) and those for whom multiple passes were required (MP group), after matching for confounding factors. Mediation analysis was performed to examine the association between FP and 3-month mRS score, with IG as mediating variable. RESULTS: A total of 200 patients were included, of whom 118 (28.9%) had FP complete reperfusion. In case-control analysis, the FP group had lower IG than the MP group [8.7 (5.4-12.9) ml vs. 15.2 (11-22.6) ml, respectively; P = 0.03). Favorable outcome was higher in the FP population compared to a matched MP population (70.9% vs. 53.2%, respectively; P = 0.04). FP compete reperfusion (eTICI 3) was independently associated with favorable outcome in multivariable regression analysis [odds ratio 1.86, 95% confidence interval (CI) 1.01-4.39; P = 0.04]. The effect of complete reperfusion at FP on functional outcome was explained by limited IG in mediation analysis [indirect effect: -0.32 (95% CI -0.47 to -0.09)]. CONCLUSION: Complete reperfusion at FP is independently associated with significant decrease in IG compared to complete reperfusion by multiple attempts, explaining better functional outcomes.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , Acidente Vascular Cerebral , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/cirurgia , Humanos , Infarto , Estudos Prospectivos , Reperfusão , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Trombectomia , Resultado do Tratamento
6.
AJNR Am J Neuroradiol ; 42(1): 42-48, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33184069

RESUMO

BACKGROUND AND PURPOSE: Collateral status and thrombus length have been independently associated with functional outcome in patients with acute ischemic stroke. It has been suggested that thrombus length would influence functional outcome via interaction with the collateral circulation. We investigated the individual and combined effects of thrombus length assessed by the clot burden score and collateral status assessed by a FLAIR vascular hyperintensity-ASPECTS rating system on functional outcome (mRS). MATERIALS AND METHODS: Patients with anterior circulation acute ischemic stroke due to large-vessel occlusion from the ASTER and THRACE trials treated with endovascular thrombectomy were pooled. The clot burden score and FLAIR vascular hyperintensity score were determined on MR imaging obtained before endovascular thrombectomy. Favorable outcome was defined as an mRS score of 0-2 at 90 days. Association of the clot burden score and the FLAIR vascular hyperintensity score with favorable outcome (individual effect and interaction) was examined using logistic regression models. RESULTS: Of the 326 patients treated by endovascular thrombectomy with both the clot burden score and FLAIR vascular hyperintensity assessment, favorable outcome was observed in 165 (51%). The rate of favorable outcome increased with clot burden score (smaller clots) and FLAIR vascular hyperintensity (better collaterals) values. The association between clot burden score and functional outcome was significantly modified by the FLAIR vascular hyperintensity score, and this association was stronger in patients with good collaterals, with an adjusted OR = 6.15 (95% CI, 1.03-36.81). CONCLUSIONS: The association between the clot burden score and functional outcome varied for different collateral scores. The FLAIR vascular hyperintensity score might be a valuable prognostic factor, especially when contrast-based vascular imaging is not available.


Assuntos
Circulação Colateral , AVC Isquêmico/patologia , AVC Isquêmico/cirurgia , Trombose/patologia , Resultado do Tratamento , Idoso , Idoso de 80 Anos ou mais , Procedimentos Endovasculares/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Trombectomia/métodos , Trombose/cirurgia
7.
Cancer Radiother ; 24(5): 453-462, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32278653

RESUMO

Neuroimaging and especially MRI has emerged as a necessary imaging modality to detect, measure, characterize and monitor brain tumours. Advanced MRI sequences such as perfusion MRI, diffusion MRI and spectroscopy as well as new post-processing techniques such as automatic segmentation of tumours and radiomics play a crucial role in characterization and follow up of brain tumours. The purpose of this review is to provide an overview on anatomical and functional MRI use for brain tumours boundaries determination and tumour characterization in the specific context of radiotherapy. The usefulness of anatomical and functional MRI on particular challenges posed by radiotherapy such as pseudo progression and pseudo esponse and new treatment strategies such as dose painting is also described.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundário , Meios de Contraste/administração & dosagem , Progressão da Doença , Glioblastoma/diagnóstico por imagem , Glioblastoma/radioterapia , Glioma/diagnóstico por imagem , Glioma/radioterapia , Humanos , Espectroscopia de Ressonância Magnética/métodos , Gradação de Tumores , Técnica de Subtração , Resultado do Tratamento
8.
BMC Med Inform Decis Mak ; 20(1): 30, 2020 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-32046699

RESUMO

BACKGROUND: Telemedicine is one of the healthcare sectors that has developed the most in recent years. Currently, telemedicine is mostly used for patients who have difficulty attending medical consultations because of where they live (teleconsultation) or for specialist referrals when no specialist of a given discipline is locally available (telexpertise). However, the use of specific equipment (with dedicated cameras, screens, and computers) and the need for institutional infrastructure made the deployment and use of these systems expensive and rigid. Although many telemedicine systems have been tested, most have not generally gone beyond local projects. Our hypothesis is that the use of smartphones will allow health care providers to overcome some of the limitations that we have exposed, thus allowing the generalization of telemedicine. MAIN BODY: This paper addresses the problem of telemedicine applications, the market of which is growing fast. Their development may completely transform the organization of healthcare systems, change the way patients are managed and revolutionize prevention. This new organization should facilitate the lives of both patients and doctors. In this paper, we examine why telemedicine has failed for years to take its rightful place in many European healthcare systems although there was a real need. By developing the example of France, this article analyses the reasons most commonly put forth: the administrative and legal difficulties, and the lack of funding. We argue that the real reason telemedicine struggled to find its place was because the technology was not close enough to the patient. CONCLUSION: Finally, we explain how the development of smartphones and their current ubiquitousness should allow the generalization of telemedicine in France and on a global scale.


Assuntos
Aplicativos Móveis , Smartphone , Telemedicina/tendências , Atenção à Saúde/tendências , França , Humanos , Consulta Remota
9.
J Colloid Interface Sci ; 564: 478-490, 2020 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-31972531

RESUMO

Recently we showed that membrane capacitive deionization (MCDI) can be used to capture CO2, but we found that the performance decreases with decreasing current density. In the present study, we investigate the effect of electrodes and ion exchange membranes by performing experiments with two membranes (CO2-MCDI), with one membrane (cation or anion exchange membrane), and without membranes (CO2-CDI). We find that the anion exchange membrane is essential to keep high CO2 absorption efficiencies ( [Formula: see text] /ncharge), while the absorption efficiency of the CO2-CDI cell was lower than expected (Λa≈0.5 for CO2-MCDI against Λa≈0.18 for CO2-CDI). Moreover, we theoretically investigate ion adsorption mechanisms in the electrodes by comparing experimental data of a CO2-CDI cell with theoretical results of the classic amphoteric-Donnan model developed for conventional CDI. By comparing the experimental results with the amph-D model, we find that the model overestimates the absorption efficiency in CO2-CDI experiments. To understand this discrepancy, we investigate the effects of other phenomena, i.e., (i) low ion concentration, (ii) passive CO2 absorption, and (iii) the effect of acid-base reactions on the chemical surface charge.

10.
J Neuroradiol ; 47(1): 5-12, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30954548

RESUMO

INTRODUCTION: The aim of this study was to assess the agreement between postmortem computed tomography (PMCT) and autopsy in detecting traumatic head injuries. MATERIALS AND METHODS: Consecutive cases of death that underwent both unenhanced PMCT and conventional autopsy were collected from our institution database during a period of 3 years and reviewed retrospectively. PMCT images were reviewed for the presence of fractures (cranial vault, skull base, facial bones and atlas/axis) and intracranial hemorrhage. Kappa values were calculated to determine the agreement between PMCT and autopsy reports. RESULTS: 73 cases were included, of which 44 (60%) had head trauma. Agreement between PMCT and autopsy was almost perfect (κ = 0.95) for fractures and substantial (κ = 0.75) for intracranial hemorrhage. PMCT was superior to autopsy in detecting facial bone and upper cervical spine fractures, and intraventricular hemorrhage. However, in some cases thin extra-axial blood collections were missed on PMCT. CONCLUSIONS: The agreement between PMCT and autopsy in detecting traumatic head injuries was good. Using a combination of both techniques increases the quality of postmortem evaluation because more lesions are detected.


Assuntos
Autopsia , Lesões Encefálicas Traumáticas/diagnóstico , Traumatismos Craniocerebrais/diagnóstico , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Lesões Encefálicas Traumáticas/patologia , Criança , Pré-Escolar , Traumatismos Craniocerebrais/patologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Neurorradiografia , Adulto Jovem
12.
Environ Sci Technol ; 52(16): 9478-9485, 2018 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-29993236

RESUMO

Capture of CO2, originating from both fossil fuels, such as coal combustion, and from renewables, such as biogas, appears to be one of the greatest technological challenges of this century. In this study, we show that membrane capacitive deionization (MCDI) can be used to capture CO2 as bicarbonate and carbonate ions produced from the reaction of CO2 with water. This novel approach allows capturing CO2 at room temperature and atmospheric pressure without the use of chemicals. In this process, the adsorption and desorption of bicarbonate ions from the deionized water solution drive the CO2(g) absorption-desorption from the gas phase. In this work, the effects of the current density and the CO2 partial pressure were studied. We found that between 55 and 75% of the electrical charge of the capacitive electrodes can be directly used to absorb CO2 gas. The energy requirement of such a system was found to be ≈40 kJ mol-1 at 15% CO2 and could be further improved by reducing the ohmic and non-ohmic energy losses of the MCDI cell.


Assuntos
Dióxido de Carbono , Purificação da Água , Adsorção , Eletrodos , Íons
14.
AJNR Am J Neuroradiol ; 39(1): 77-83, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29074634

RESUMO

BACKGROUND AND PURPOSE: In acute ischemic stroke, whether FLAIR vascular hyperintensities represent good or poor collaterals remains controversial. We hypothesized that extensive FLAIR vascular hyperintensities correspond to good collaterals, as indirectly assessed by the hypoperfusion intensity ratio. MATERIALS AND METHODS: We included 244 consecutive patients eligible for reperfusion therapy with MCA stroke and pretreatment MR imaging with both FLAIR and PWI. The FLAIR vascular hyperintensity score was based on ASPECTS, ranging from 0 (no FLAIR vascular hyperintensity) to 7 (FLAIR vascular hyperintensities abutting all ASPECTS cortical areas). The hypoperfusion intensity ratio was defined as the ratio of the time-to-maximum >10-second over time-to-maximum >6-second lesion volumes. The median hypoperfusion intensity ratio was used to dichotomize good (low hypoperfusion intensity ratio) versus poor (high hypoperfusion intensity ratio) collaterals. We then studied the association between FLAIR vascular hyperintensity extent and hypoperfusion intensity ratio. RESULTS: Hypoperfusion was present in all patients, with a median hypoperfusion intensity ratio of 0.35 (interquartile range, 0.19-0.48). The median FLAIR vascular hyperintensity score was 4 (interquartile range, 3-5). The FLAIR vascular hyperintensities were more extensive in patients with good collaterals (hypoperfusion intensity ratio ≤0.35) than with poor collaterals (hypoperfusion intensity ratio >0.35; P for Trend = .016). The FLAIR vascular hyperintensity score was independently associated with good collaterals (P for Trend = .002). CONCLUSIONS: In patients eligible for reperfusion therapy, FLAIR vascular hyperintensity extent was associated with good collaterals, as assessed by the pretreatment hypoperfusion intensity ratio. The ASPECTS assessment of FLAIR vascular hyperintensities could be used to rapidly identify patients more likely to benefit from reperfusion therapy.


Assuntos
Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Circulação Colateral , Imageamento por Ressonância Magnética/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reperfusão , Estudos Retrospectivos , Acidente Vascular Cerebral/terapia
15.
Vet Microbiol ; 207: 205-209, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28757025

RESUMO

An episode of acute equine respiratory infection was reported in western Algeria (Tiaret province) between February and March 2011, affecting a large population of horses. Nasal swabs (n=100) were taken from horses aged between 1 and 27 years, presenting with cough and mucopurulent nasal discharge. The prevalence of equine respiratory virus infections was examined using quantitative polymerase chain reaction (qPCR). One, or more, of four equine respiratory viruses were detected in the nasal swabs of 90 of 100 horses (90%) and the detection rate of equine herpesvirus type 1 (EHV-1), equine herpesvirus type 4 (EHV-4), equine herpesvirus type 2 (EHV-2) and equine herpesvirus type 5 (EHV-5) were 2%, 14%, 90% and 75%, respectively. Equine influenza virus and equine arteritis virus were not detected in any samples. Among the 90 infected horses, 70 were co-infected with EHV-2 and EHV-5 and 14 others were co-infected with EHV-4, EHV-2 and EHV-5. The present study shows a positivity rate of 97.3% for EHV-5 in young horses aged <3years; a finding which decreased with age. Viral load of EHV-5 was significantly higher in <3years whereas no effect of age was observed with EHV-2. The study shows that equine herpesviruses 1, 2, 4 and 5 are endemic in horse populations from Algeria as detected for the first time by qPCR.


Assuntos
Alphaherpesvirinae/isolamento & purificação , Gammaherpesvirinae/isolamento & purificação , Doenças dos Cavalos/virologia , Argélia/epidemiologia , Animais , Doenças dos Cavalos/epidemiologia , Cavalos
16.
Neurochirurgie ; 63(3): 129-134, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28506488

RESUMO

Surgical resection of gliomas involving eloquent brain areas must be maximal in order to improve patients' survival, and safe to prevent postoperative impairments. Therefore, the precise spatial relationship between the lesion and eloquent brain areas needs to be established. Functional magnetic resonance imaging and diffusion tensor imaging are robust methods with increasing indications in neurosurgery for past decade. The aim of this review article is not only to pinpoint the major limitations of these methods in order to avoid erroneous conclusions, but also to detail practical aspects associated with the main paradigms routinely used in functional magnetic resonance imaging, and to discuss recent validation of functional magnetic resonance imaging and diffusion tensor imaging results with direct electrical stimulation during awake surgery.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neuroimagem Funcional , Glioma/diagnóstico por imagem , Mapeamento Encefálico/métodos , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Imagem de Tensor de Difusão/métodos , Neuroimagem Funcional/métodos , Glioma/cirurgia , Humanos , Neuronavegação/métodos , Resultado do Tratamento
17.
J Neuroradiol ; 44(3): 192-197, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28237365

RESUMO

BACKGROUND AND PURPOSE: Triage imaging facilitates the timely recognition of acute stroke with prognostic implications. Improvement in MR acquisition speed is needed given the extreme time constraints before treatment. We compared an ultrafast Echo-Planar FLAIR sequence (EPI-FLAIR) and a conventional FLAIR sequence (cFLAIR) for their diagnostic performances and ability to estimate the age of infarction. MATERIAL AND METHODS: Between June and August 2014, 125 consecutive patients (age 69±18 years, 48% men) admitted for a suspicion of acute (≤48-hrs) stroke were explored by both FLAIR sequences at 1.5-Tesla. EPI-FLAIR (15-sec) and cFLAIR (2-min and 15-sec) were compared by two readers, blinded to clinical data. RESULTS: EPI-FLAIR was less prone to kinetic artefacts than cFLAIR (2-3% vs. 23-49% depending on the reader, P<0.001). Diagnostic concordance was excellent for both readers (к>0.9). Amongst 8 hemorrhages, one subarachnoid hemorrhage presenting as a sudden deficit was missed on EPI-FLAIR sequence. Amongst 60 infarctions, cFLAIR and EPI-FLAIR were concordant in 50 (83%), while signal changes were visible on cFLAIR only in the remaining 10 (17%) cases. Amongst the 43 patients with known onset time (n=17 within 4.5hrs), FLAIR-DWI mismatch identified<4.5-hrs infarction with the same sensitivity (65%) using cFLAIR and EPI-FLAIR, but the positive predictive value (PPV) was higher for cFLAIR than for EPI-FLAIR (73% vs. 50%, P=0.008). CONCLUSION: EPI-FLAIR allows a drastic reduction of acquisition time devoted to FLAIR sequence and minimizes motion artifacts. Compared with cFLAIR, it is however associated with increased risk of undiagnosed stroke mimics and lower PPV for identifying<4.5-hrs infarctions.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Imagem Ecoplanar/métodos , Aumento da Imagem/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Idoso , Artefatos , Diagnóstico Diferencial , Diagnóstico por Imagem , Feminino , Humanos , Masculino , Estudos Retrospectivos , Sensibilidade e Especificidade
18.
Equine Vet J ; 47(2): 207-11, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25763436

RESUMO

UNLABELLED: REASON FOR PERFORMING THIS STUDY: Equine influenza virus (EIV) is considered the most economically important equine respiratory pathogen worldwide. The H3N8 subtype, responsible for all outbreaks of equine influenza globally, evolves perpetually. Mutations in the genome of these viruses have the potential to modify their antigenic properties and recognition by pre-existing antibodies. OBJECTIVES: The aim of this study was to determine the genetic evolution of EIV strains in France and to compare it with the evolution of strains isolated globally. Analysis of the sequence data was performed to investigate any possible links between the outbreaks. STUDY DESIGN: Retrospective genetic analysis study of archived material. METHODS: Analyses were performed on the HA1 domain of haemagglutinin H3 of EIV isolated in a previous study carried out from November 2005 to October 2010. The nucleic acid sequence of 41 strains was analysed and translated. The French viruses were compared with 59 Clade 1 strains and 83 Clade 2 strains. Strains were aligned chronologically and on the basis of their geographical origin. RESULTS: The 16 Clade 1 strains are all derived from the outbreak that started in the Grosbois training yard in 2009. The virus genome appears to have been stable during the outbreak. The 25 Clade 2 strains were isolated over the 5-year period during which several mutations had emerged. Some strains incorporate a sporadic mutation, and others a mutation that may occur several times but does not persist. However, all strains are gradually moving towards definitive mutations. CONCLUSION: This study demonstrated that EIVs have evolved in France during this period in a similar manner to EIVs globally. The data lend support to the current World Animal Health Organisation recommendation that the vaccines contain a representative of both Clade 1 and Clade 2 of the Florida sublineage.


Assuntos
Evolução Biológica , Doenças dos Cavalos/virologia , Vírus da Influenza A Subtipo H3N8/genética , Infecções por Orthomyxoviridae/veterinária , Sequência de Aminoácidos , Animais , Surtos de Doenças/veterinária , França/epidemiologia , Regulação Viral da Expressão Gênica/fisiologia , Doenças dos Cavalos/epidemiologia , Cavalos , Vírus da Influenza A Subtipo H3N8/isolamento & purificação , Dados de Sequência Molecular , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/virologia , Estudos Retrospectivos , Proteínas Virais/genética , Proteínas Virais/metabolismo
19.
AJNR Am J Neuroradiol ; 36(2): 269-74, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25190202

RESUMO

BACKGROUND AND PURPOSE: In acute stroke with proximal artery occlusion, FLAIR vascular hyperintensities observed beyond the boundaries of the cortical lesion on DWI (newly defined "FLAIR vascular hyperintensity-DWI mismatch") may be a marker of tissue at risk of infarction. Our aim was to compare the occurrence of FLAIR vascular hyperintensity-DWI mismatch relative to that of perfusion-weighted imaging-DWI mismatch in patients with proximal MCA occlusion before IV thrombolysis. MATERIALS AND METHODS: In 141 consecutive patients with proximal MCA occlusion, 2 independent observers analyzed FLAIR images for the presence of FLAIR vascular hyperintensity-DWI mismatch before IV thrombolysis. PWI-DWI mismatch was defined as Volumehypoperfusion > 1.8 × VolumeDWI, with Volumehypoperfusion > 6 seconds on time to maximum value of the residue function maps in the 94 patients with available PWI. The presence of FLAIR vascular hyperintensity-DWI mismatch, PWI-DWI mismatch, and infarct growth on 24-hour follow-up DWI was compared. RESULTS: A FLAIR vascular hyperintensity-DWI mismatch was present in 102/141 (72%) patients, with an excellent interobserver reliability (κ = 0.91), and a PWI-DWI mismatch, in 61 of the 94 (65%) patients with available PWI. FLAIR vascular hyperintensity-DWI mismatch predicted PWI-DWI mismatch with a sensitivity of 92% (95% CI, 85%-99%) and a specificity of 64% (95% CI, 47%-80%). Patients with FLAIR vascular hyperintensity-DWI mismatch had smaller initial DWI lesion and larger infarct growth (P < .001) than patients without FLAIR vascular hyperintensity-DWI mismatch, even though their final infarcts remained smaller (P < .001). CONCLUSIONS: Albeit being moderately specific, probably due to inclusion of oligemic tissue, the FLAIR vascular hyperintensity-DWI mismatch identifies large PWI-DWI mismatch with high sensitivity.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Infarto da Artéria Cerebral Média/patologia , Acidente Vascular Cerebral/sangue , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Acidente Vascular Cerebral/patologia
20.
Transbound Emerg Dis ; 62(6): 623-31, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24472362

RESUMO

An outbreak of equine influenza (EI) was reported in Algeria between May and July, 2011. The outbreak started in Tiaret, in west province of Algeria, and spread to the other parts of the country affecting almost 900 horses in many provinces. The population studied was composed of 325 horses from different groups of age. Clinical sign expression was age dependent. Indeed, a morbidity rate of 14.9% was observed in horses under 15 months old and a rate of 4.95% in horses over 8 years old. Interestingly, the morbidity rate raised sharply to reach 100% in horses aged between 18 months and 7 years. The virus (H3N8) was detected in nasopharyngeal swabs (n = 11) from non-vaccinated horses using a qRT-PCR targeting a portion of the gene encoding the matrix protein (M). The virus isolates were identified as H3N8 by sequencing the haemagglutinin (HA) and neuraminidase (NA) genes and were named from A/equine/Tiaret/1/2011 to A/equine/Tiaret/10/2011. Alignment of HA1 amino acid sequence confirmed that viruses belong to Clade 2 of the Florida sublineage in the American lineage. Moreover, they are closely related to A/equine/Yokohama/aq13/2010, A/equine/Eyragues/1/2010, A/equine/Bokel/2011 and A/equine/Lichtenfeld/2012. Our data indicate that this strain was also circulating in the European horse population in 2010, 2011 and 2012.


Assuntos
Surtos de Doenças/veterinária , Doenças dos Cavalos/epidemiologia , Vírus da Influenza A Subtipo H3N8/genética , Infecções por Orthomyxoviridae/veterinária , Argélia/epidemiologia , Sequência de Aminoácidos , Animais , Hemaglutininas/genética , Doenças dos Cavalos/virologia , Cavalos , Vírus da Influenza A/genética , Dados de Sequência Molecular , Neuraminidase/genética , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/virologia , Filogenia , Proteínas da Matriz Viral/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...