19 research outputs found
Effects of systolic blood pressure on brain integrity in multiple sclerosis
Background: In MS patients, hypertension is associated with a delayed diagnosis and an increased risk of progression. Understanding the mechanisms of this association could potentially lead to improved prevention of disease progression. We aimed to establish whether high blood pressure contributes to white-matter injury and brain atrophy in MS. Methods: Cross-sectional study of 95 patients with RRMS. Estimates of fractional anisotropy, gray-matter volume and lesion load were obtained from 3T MRI. We used fractional anisotropy voxel-based statistics to establish the effect of blood pressure on white matter tracts. Additionally, we used voxel-based morphometry (VBM) to study the effect on gray matter integrity. Results: Only 29.5% had normal blood pressure levels, with 52.6% suffering from prehypertension and 17.9% with hypertension. Increasing systolic blood pressure was associated with damage to posterior white-matter tracts as well as greater levels of gray matter atrophy, in particular in the frontal cortex. Age-adjusted linear regression indicated that neither lesion volume (β = 0.002, 95%CI: 0.02-0.02; p = 0.85) or lesion number (β = -0.004, 95%CI: 0.03-0.02; p = 0.74) were associated with systolic blood pressure. Conclusions: Prehypertension and hypertension are frequent in MS. Increased blood pressure is related to white- and gray-matter integrity, both related to MS disability outcomes. These findings suggest attention to the control of blood pressure in MS patients.Fil: Dossi, Daiana. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; ArgentinaFil: Chaves, Hernán. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; ArgentinaFil: Heck, Evelyn Sabrina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; ArgentinaFil: Rodriguez Murua, Sofia. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ventrice, Fernando. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; ArgentinaFil: Bakshi, Rohit. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; ArgentinaFil: Quintana, Francisco Javier. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; ArgentinaFil: Correale, Jorge. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; ArgentinaFil: Farez, Mauricio Franco. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia. Instituto de Neurociencias - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Neurociencias; Argentin
Brain volumes quantification from MRI in healthy controls: Assessing correlation, agreement and robustness of a convolutional neural network-based software against FreeSurfer, CAT12 and FSL
Background and purpose: There are instances in which an estimate of the brain volume should be obtained from MRI in clinical practice. Our objective is to calculate cross-sectional robustness of a convolutional neural network (CNN) based software (Entelai Pic) for brain volume estimation and compare it to traditional software such as FreeSurfer, CAT12 and FSL in healthy controls (HC). Materials and Methods: Sixteen HC were scanned four times, two different days on two different MRI scanners (1.5 T and 3 T). Volumetric T1-weighted images were acquired and post-processed with FreeSurfer v6.0.0, Entelai Pic v2, CAT12 v12.5 and FSL v5.0.9. Whole-brain, grey matter (GM), white matter (WM) and cerebrospinal fluid (CSF) volumes were calculated. Correlation and agreement between methods was assessed using intraclass correlation coefficient (ICC) and Bland Altman plots. Robustness was assessed using the coefficient of variation (CV). Results: Whole-brain volume estimation had better correlation between FreeSurfer and Entelai Pic (ICC (95% CI) 0.96 (0.94−0.97)) than FreeSurfer and CAT12 (0.92 (0.88−0.96)) and FSL (0.87 (0.79−0.91)). WM, GM and CSF showed a similar trend. Compared to FreeSurfer, Entelai Pic provided similarly robust segmentations of brain volumes both on same-scanner (mean CV 1.07, range 0.20–3.13% vs. mean CV 1.05, range 0.21–3.20%, p = 0.86) and on different-scanner variables (mean CV 3.84, range 2.49–5.91% vs. mean CV 3.84, range 2.62–5.13%, p = 0.96). Mean post-processing times were 480, 5, 40 and 5 min for FreeSurfer, Entelai Pic, CAT12 and FSL respectively. Conclusion: Based on robustness and processing times, our CNN-based model is suitable for cross-sectional volumetry on clinical practice.Fil: Chaves, Hernan. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; ArgentinaFil: Dorr, Francisco. Entelai; ArgentinaFil: Costa, Martín Elías. Entelai; ArgentinaFil: Serra, María Mercedes. Entelai; Argentina. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; ArgentinaFil: Fernandez Slezak, Diego. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; Argentina. Entelai; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigación en Ciencias de la Computación. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigación en Ciencias de la Computación; ArgentinaFil: Farez, Mauricio Franco. Entelai; Argentina. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Sevlever, Gustavo. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; Argentina. Entelai; ArgentinaFil: Yañez, Paulina Celia. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; Argentina. Universidad de Buenos Aires; ArgentinaFil: Cejas, Claudia. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; Argentin
Lesiones medulares catastróficas en el rugby argentino. Impacto de las medidas implementadas y su reducción relativa en el tiempo
Introducción: Se entiende por lesión catastrófica a cualquier trauma grave que comprometa la cabeza, el cerebro, la columna vertebral o la médula espinal, que pone en riesgo la vida o puede dejar una discapacidad permanente o semipermanente. En la Argentina, la incidencia de lesionados en el ámbito del rugby es alta comparada con la de otros países. En los últimos años, se han implementado múltiples medidas de prevención y se han modificado normas con el objetivo de evitar las lesiones catastróficas.
Materiales y Métodos: Se analizaron datos obtenidos de una encuesta telefónica realizada en el marco de colaboración entre la Unión Argentina de Rugby y la Fundación para la Lucha de Enfermedades Neurológicas de la Infancia (Fleni). Se realizó un análisis descriptivo de los datos. Se recopilaron los cambios en las normativas del deporte, que pudieran tener impacto en las futuras lesiones.
Resultados: Se observa que el número de lesiones se mantiene estable año tras año. Al asociar este dato con un aumento sostenido de la cantidad de jugadores por año, impresiona haber una disminución relativa del riesgo de lesionarse.
Conclusiones: Las lesiones catastróficas generan un gran impacto en la calidad de vida del jugador y de su entorno. Deben considerarse inadmisibles y se deben incrementar los esfuerzos para lograr eliminar los riesgos de lesionarse. El esfuerzo de las entidades reguladoras impresiona tener un impacto positivo al haberse logrado una reducción relativa de las lesiones en relación con el aumento de jugadores año tras año
COVID-19 pneumonia accurately detected on chest radiographs with artificial intelligence
PurposeTo investigate the diagnostic performance of an Artificial Intelligence (AI) system for detection of COVID-19 in chest radiographs (CXR), and compare results to those of physicians working alone, or with AI support.Materials and methodsAn AI system was fine-tuned to discriminate confirmed COVID-19 pneumonia, from other viral and bacterial pneumonia and non-pneumonia patients and used to review 302 CXR images from adult patients retrospectively sourced from nine different databases. Fifty-four physicians blind to diagnosis, were invited to interpret images under identical conditions in a test set, and randomly assigned either to receive or not receive support from the AI system. Comparisons were then made between diagnostic performance of physicians working with and without AI support. AI system performance was evaluated using the area under the receiver operating characteristic (AUROC), and sensitivity and specificity of physician performance compared to that of the AI system.ResultsDiscrimination by the AI system of COVID-19 pneumonia showed an AUROC curve of 0.96 in the validation and 0.83 in the external test set, respectively. The AI system outperformed physicians in the AUROC overall (70% increase in sensitivity and 1% increase in specificity, p < 0.0001). When working with AI support, physicians increased their diagnostic sensitivity from 47% to 61% (p < 0.001), although specificity decreased from 79% to 75% (p = 0.007).ConclusionsOur results suggest interpreting chest radiographs (CXR) supported by AI, increases physician diagnostic sensitivity for COVID-19 detection. This approach involving a human-machine partnership may help expedite triaging efforts and improve resource allocation in the current crisis.Fil: Dorr, Francisco. Entelai; ArgentinaFil: Chaves, Hernán. Entelai; Argentina. Fundación P/la Lucha C/enferm. neurológicas Infancia. Instituto de Neurociencias. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Neurociencias; ArgentinaFil: Serra, María Mercedes. Entelai; Argentina. Fundación P/la Lucha C/enferm. neurológicas Infancia. Instituto de Neurociencias. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Neurociencias; ArgentinaFil: Ramirez, Andres. Entelai; ArgentinaFil: Costa, Martín Elías. Entelai; ArgentinaFil: Seia, Joaquín Oscar. Entelai; ArgentinaFil: Cejas, Claudia. Fundación P/la Lucha C/enferm. neurológicas Infancia. Instituto de Neurociencias. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Neurociencias; ArgentinaFil: Castro, Marcelo. Departamento de Diagnóstico por Imágenes, Clínica Indisa ; ChileFil: Eyheremendy, Eduardo. Hospital Alemán; ArgentinaFil: Fernández Slezak, Diego. Entelai; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigación en Ciencias de la Computación. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigación en Ciencias de la Computación; ArgentinaFil: Farez, Mauricio Franco. Entelai; Argentina. Fundación P/la Lucha C/enferm. neurológicas Infancia. Instituto de Neurociencias. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Neurociencias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
CONDUÇÃO E DOENÇA DE ALZHEIMER: UMA BATERIA DE TRIAGEM NEUROPSICOLÓGICA PARA IDOSOS
As life expectancy increases, there is a marked increase in the elderly population eager to continue driving. A large proportion of these elderly drive safely, however, patients with mild dementia are high-risk drivers.
Objective:
to identify the cognitive tests that best predict driving ability in subjects with mild dementia.
Methods:
28 drivers with mild dementia and 28 healthy elderly subjects underwent an extensive cognitive assessment (NACC Uniform Data Set Neuropsychological Battery), completed an adapted On Road Driving Test (ORDT) and a Driving Simulator assessment.
Results:
drivers with mild dementia made more mistakes on the ORDT and had slower responses in the simulator tasks. Cognitive tests correlated strongly with on road and simulator driving performance. Age, the Digit Symbol Modalities Test and Boston Naming Test scores were the variables that best predicted performance on the ORDT and were included in a logistic regression model.
Conclusion:
the strong correlation between driving performance and performance on specific cognitive tests supports the importance of cognitive assessment as a useful tool for deciding whether patients with mild dementia can drive safely. The algorithm including these three variables could be used as a screening tool for the detection of unsafe driving in elderly subjects with cognitive decline
Salt intake in multiple sclerosis: Friend or foe?
High sodium intake has been recently noted as a putative environmental factor linked to multiple sclerosis. In their JNNP publication, Nourbakhsh and colleagues1 report a multicentric study of patients with paediatric multiple sclerosis where no association was detected between sodium intake and time to relapse.Fil: Farez, Mauricio Franco. Instituto de Investigaciones Neurologicas Raul Carrera; Argentina. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
People with MS should consume a low-salt diet - YES
Fil: Farez, Mauricio Franco. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Correale, Jorge. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; Argentin
Does helminth activation of Toll-Like Receptors modulate immune response in Multiple Sclerosis patients?
Multiple sclerosis (MS) is an inflammatory autoimmune demyelinating disease affecting the Central Nervous System, in which Th1 and Th17 cells appear to recognize and react against certain myelin sheath components.Epidemiological evidence has accumulated indicating steady increase in autoimmune disease incidence in developed countries. Reduced infectious disease prevalence in particular has been proposed as the cause. In agreement with this hypothesis, we recently demonstrated significantly better clinical and radiological outcome in helminth-infected MS patients, compared to uninfected ones. Parasite-driven protection was associated with regulatory T cell induction and anti-inflammatory cytokine secretion, including increased TGF-β and IL-10 levels. Interestingly, surface expression of TLR2, on both B cells and dendritic cells (DC) was significantly higher in infected MS patients. Moreover, stimulation of myelin-specific T cell lines with a TLR2 agonist induced inhibition of T cell proliferation, suppression of IFN-γ, IL-12 and IL-17 secretion, as well as increase in IL-10 production, suggesting the functional responses observed correlate with TLR2 expression patterns. Furthermore, parasite antigens were able to induce TLR2 expression on both B cells and DCs. All functional effects mediated by TLR2 were abrogated when MyD88 gene expression was silenced; indicating helminth–mediated signaling induced changes in cytokine secretion in a MyD88-dependent manner.In addition, helminth antigens significantly enhanced co-stimulatory molecule expression, effects not mediated by MyD88. Parasite antigens acting on MyD88 induced significant ERK kinase phosphorylation in DC. Addition of the ERK inhibitor U0126 was associated with dose-dependent IL-10 inhibition and reciprocal enhancement in IL-12, both correlating with ERK inhibition. Finally, cytokine effects and changes observed in co-stimulatory DC molecules after helminth antigen exposure were lost when TLR2 was sil
Environmental factors influencing multiple sclerosis in Latin America
It is generally accepted that autoimmune diseases like multiple sclerosis (MS) arise from complex interactions between genetic susceptibility and environmental factors. Genetic variants confer predis- position to develop MS, but cannot be therapeutically modified. On the other hand, several studies have shown that different lifestyle and environmental factors influence disease development, as well as activity levels and progression. Unlike genetic risk factors, these can be modified, with potential for prevention, particularly in high-risk populations. Most studies identifying particular lifestyle and environmental factors have been carried out in Caucasian patients with MS. Little or no data is available on the behavior of these factors in Latin American populations. Ethnic and geographic differences between Latin America and other world regions suggest potential regional variations in MS, at least with respect to some of these factors. Furthermore, particular environmental characteristics observed more frequently in Latin America could explain regional differences in MS prevalence. Site-specific studies exploring influences of local environmental factors are warranted.Fil: Correale, Jorge. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; ArgentinaFil: Farez, Mauricio Franco. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; ArgentinaFil: Gaitán, María Inés. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; Argentin
Age may contribute to the increased frequency of axonal Guillain-Barré syndrome
Introduction: The frequency of axonal Guillain-Barré syndrome (GBS) varies among countries. Previous studies supporting the high frequency of axonal GBS in South America have been carried out with pediatric populations. We seek to determine the frequency of axonal GBS in both children and adults in South America. Methods: This is a retrospective cohort analysis of patients who were diagnosed with GBS between January 2006 and December 2013 in a neurological center in Buenos Aires, Argentina. Adults and children with a diagnosis of GBS were included and classified by applying Ho and colleagues' criteria1 for axonal GBS. Results: The study included 105 patients with GBS. Among 58 adults, only 5 individuals were classified as axonal GBS compared with 16 of 47 children. The frequency of axonal GBS was significantly higher in children than in adults (34% vs. 8.6%, P = 0.0001). Discussion: As shown in a cohort of South American patients, age may impact the frequency of axonal GBS.Fil: Hawkes, Maximiliano A.. Mayo Clinic; Estados UnidosFil: Wilken, Miguel. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; ArgentinaFil: Vázquez, Gabriel. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; ArgentinaFil: Farez, Mauricio Franco. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; Argentin