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1.
J Med Virol ; 95(5): e28786, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37212340

RESUMO

The aim of this study was to analyze whether the coronavirus disease 2019 (COVID-19) vaccine reduces mortality in patients with moderate or severe COVID-19 disease requiring oxygen therapy. A retrospective cohort study, with data from 148 hospitals in both Spain (111 hospitals) and Argentina (37 hospitals), was conducted. We evaluated hospitalized patients for COVID-19 older than 18 years with oxygen requirements. Vaccine protection against death was assessed through a multivariable logistic regression and propensity score matching. We also performed a subgroup analysis according to vaccine type. The adjusted model was used to determine the population attributable risk. Between January 2020 and May 2022, we evaluated 21,479 COVID-19 hospitalized patients with oxygen requirements. Of these, 338 (1.5%) patients received a single dose of the COVID-19 vaccine and 379 (1.8%) were fully vaccinated. In vaccinated patients, mortality was 20.9% (95% confidence interval [CI]: 17.9-24), compared to 19.5% (95% CI: 19-20) in unvaccinated patients, resulting in a crude odds ratio (OR) of 1.07 (95% CI: 0.89-1.29; p = 0.41). However, after considering the multiple comorbidities in the vaccinated group, the adjusted OR was 0.73 (95% CI: 0.56-0.95; p = 0.02) with a population attributable risk reduction of 4.3% (95% CI: 1-5). The higher risk reduction for mortality was with messenger RNA (mRNA) BNT162b2 (Pfizer) (OR 0.37; 95% CI: 0.23-0.59; p < 0.01), ChAdOx1 nCoV-19 (AstraZeneca) (OR 0.42; 95% CI: 0.20-0.86; p = 0.02), and mRNA-1273 (Moderna) (OR 0.68; 95% CI: 0.41-1.12; p = 0.13), and lower with Gam-COVID-Vac (Sputnik) (OR 0.93; 95% CI: 0.6-1.45; p = 0.76). COVID-19 vaccines significantly reduce the probability of death in patients suffering from a moderate or severe disease (oxygen therapy).


Assuntos
COVID-19 , Vacinas , Humanos , Vacinas contra COVID-19 , Oxigênio , ChAdOx1 nCoV-19 , Vacina BNT162 , Estudos de Coortes , Estudos Retrospectivos , COVID-19/prevenção & controle , RNA Mensageiro
2.
Rev. salud pública ; 21(5): e176765, sep.-oct. 2019. tab, graf
Artigo em Espanhol, Português | LILACS | ID: biblio-1099275

RESUMO

RESUMEN Objetivo Traducir y adaptar culturalmente el cuestionario Exercise Fear Avoidance Scale (EFAS) al español para su uso en adultos mayores chilenos. Materiales y Métodos Doble traducción directa con armonización de versiones, retro-traducción y análisis de la comprensibilidad mediante entrevistas cognitivas. En el proceso de entrevistas cognitivas participaron 20 adultos mayores con edades comprendidas entre 63 y 83 años. Resultados Todos los ítems fueron evaluados como claros y comprensibles. Mediante la técnica de parafraseo e indagación 3 ítems (de un total de 16) se tuvieron que adaptar para lograr una mejor comprensión. Dos de estas adaptaciones consistieron en reemplazar un concepto por uno más utilizado en el contexto chileno y otra modificación fue en relación con la redacción, puesto que su lectura resultaba compleja para esta población. Conclusiones Se obtuvo una versión en español del cuestionario EFAS, la cual demostró ser comprensible y adaptada para su uso en adultos mayores chilenos.(AU)


ABSTRACT Objective To translate and culturally adapt the Exercise Fear Avoidance Scale (EFAS) Into Spanish for Chilean older adults. Materials and Methods Double direct translation with harmonization, back translation and analysis of text comprehensibility through cognitive interviews. A sample of 20 older adults between the ages of 63 and 83 participated in the cognitive interview process. Results All items were assessed as clear and understandable. Using the paraphrasing and inquiry techniques, 3 items (out of 16) were adapted to achieve better understanding. Two of these adaptations consisted in replacing one concept with another, as the latter was more used in the Chilean context, and making a non-literal translation, since the literal one was too complex for the elderly to understand. Conclusions A Spanish version of the EFAS was obtained, which proved to be understandable and adapted for its use with Chilean older adults.(AU)


OBJETIVO Traduza e adapte culturalmente o questionário da Escala de Evitação do Medo do Exercício (EFAS) ao espanhol para uso em idosos chilenos. MATERIAIS E MÉTODOS Tradução direta dupla com harmonização de versões, retrotradução e análise de compreensibilidade por meio de entrevistas cognitivas. Vinte idosos entre 63 e 83 anos participaram do processo de entrevista cognitiva. RESULTADOS Todos os itens foram avaliados como claros e compreensíveis. Usando a paráfrase e a técnica de investigação, três itens (de um total de 16) tiveram que ser adaptados para alcançar uma melhor compreensão. Duas dessas adaptações consistiram em substituir um conceito por outro mais utilizado no contexto chileno e outra modificação em relação à redação, uma vez que sua leitura era complexa para essa população. CONCLUSÕES Foi obtida uma versão em espanhol do questionário EFAS, que se mostrou compreensível e adaptado para uso em idosos chilenos.(AU)


Assuntos
Humanos , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Exercício Físico , Medo/psicologia , Chile , Inquéritos e Questionários
3.
Rev Salud Publica (Bogota) ; 21(5): 479-484, 2019 09 01.
Artigo em Espanhol | MEDLINE | ID: mdl-36753197

RESUMO

OBJECTIVE: To translate and culturally adapt the Exercise Fear Avoidance Scale (EFAS) Into Spanish for Chilean older adults. MATERIALS AND METHODS: Double direct translation with harmonization, back translation and analysis of text comprehensibility through cognitive interviews. A sample of 20 older adults between the ages of 63 and 83 participated in the cognitive interview process. RESULTS: All items were assessed as clear and understandable. Using the paraphrasing and inquiry techniques, 3 items (out of 16) were adapted to achieve better understanding. Two of these adaptations consisted in replacing one concept with another, as the latter was more used in the Chilean context, and making a non-literal translation, since the literal one was too complex for the elderly to understand. CONCLUSIONS: A Spanish version of the EFAS was obtained, which proved to be understandable and adapted for its use with Chilean older adults.


OBJETIVO: Traducir y adaptar culturalmente el cuestionario Exercise Fear Avoidance Scale (EFAS) al español para su uso en adultos mayores chilenos. MATERIALES Y MÉTODOS: Doble traducción directa con armonización de versiones, retro-traducción y análisis de la comprensibilidad mediante entrevistas cognitivas. En el proceso de entrevistas cognitivas participaron 20 adultos mayores con edades comprendidas entre 63 y 83 años. RESULTADOS: Todos los ítems fueron evaluados como claros y comprensibles. Mediante la técnica de parafraseo e indagación 3 ítems (de un total de 16) se tuvieron que adaptar para lograr una mejor comprensión. Dos de estas adaptaciones consistieron en reemplazar un concepto por uno más utilizado en el contexto chileno y otra modificación fue en relación con la redacción, puesto que su lectura resultaba compleja para esta población. CONCLUSIONES: Se obtuvo una versión en español del cuestionario EFAS, la cual demostró ser comprensible y adaptada para su uso en adultos mayores chilenos.


Assuntos
Exercício Físico , Traduções , Humanos , Idoso , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Chile , Inquéritos e Questionários , Medo , Comparação Transcultural , Reprodutibilidade dos Testes
4.
Rev. esp. salud pública ; 89(6): 563-573, nov.-dic. 2015. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-146954

RESUMO

Fundamento. Dada la importancia de las tasas de mortalidad en cada grupo socioeconómico, como explicación de la variación en las desigualdades de mortalidad entre las poblaciones, el objetivo del presente estudio es evaluar si la variación regional en las desigualdades de mortalidad en España está relacionado con las tasas de mortalidad en diferentes grupos socioeconómicos. Métodos. El estudio incluyó a todas las personas de 30-74 años que vivían en España en 2001 y a las que se realizó un seguimiento para conocer su estado vital más de 7 años. En cada una de las 17 comunidades autónomas se han estimado las tasas de mortalidad en personas con bajo y con alto nivel educativo, así como dos medidas de desigualdad de la mortalidad de acuerdo a la educación: diferencia de tasas de mortalidad y razón de tasas de mortalidad. Se calculó el valor de la mediana de las desigualdades de mortalidad en las comunidades autónomas con las tasas de mortalidad más altas y bajas y en aquellas con las tasas de mortalidad intermedias. Y se estimó el coeficiente de correlación de Pearson para evaluar la relación entre las tasas de mortalidad y las medidas de desigualdad en mortalidad. Resultados. Los coeficientes de correlación de la tasa de mortalidad en personas con bajo nivel educativo con la diferencia de tasa de mortalidad y con la razón de tasas de mortalidad fueron 0,87 y 0,78 en mujeres y 0,81 y 0,73 en los hombres, respectivamente. Los coeficientes de correlación de la tasa de mortalidad en personas con alto nivel educativo con la diferencia de tasa de mortalidad y con la razón de tasas de mortalidad fueron -0,07 y -0,24 en mujeres y 0,10 y -0,06 en los hombres, respectivamente. Conclusión. Las comunidades autónomas con las tasas de mortalidad más bajas y más altas en las personas con bajo nivel educativo generalmente tienen las menores y las mayores desigualdades en mortalidad. La variación en la magnitud de las desigualdades en mortalidad de un lugar a otro puede ser explicada por la variación en la tasa de la mortalidad en las personas con bajo nivel educativo.No se observó relación entre la tasa de mortalidad en personas con alto nivel educativo y las desigualdades de la mortalidad. (AU)


Background. Given the importance of mortality rates in each socioeconomic group, as explanation for the variation in mortality inequalities across populations, the objective of the present study is to evaluate whether regional variation in mortality inequalities in Spain is related to the mortality rates in different socioeconomic groups. Methods. The study included all persons aged 30-74 years living in Spain in 2001 and followed up for mortality over 7 years. In each of the 17 autonomous communities of Spain mortality rates were estimated for those with low and high education, as well as two measures of mortality inequality according to education: mortality rate difference and mortality rate ratio. Median value of mortality inequalities was calculated for the regions with the highest and lowest mortality rates and for those with intermediate mortality rates. And the Pearson correlation coefficient was used to estimate the relation between mortality rates and the measures of mortality inequality. Results. The correlation coefficients between mortality rate in low education and mortality rate difference and mortality rate ratio were 0.87 and 0.78 in women and 0.81 and 0.73 in men, respectively. The correlation coefficients between mortality rate in high education and mortality rate difference and mortality rate ratio were -0.07 and -0.24 in women and 0.10 and -0.06 in men, respectively. Conclusion. Regions with the lowest and highest mortality rates in low education people generally had the lowest and highest inequalities in mortality. The variation in the magnitude of inequalities in mortality from one place to another can be explained by the variation in mortality in low education people. No relation was observed between mortality rate in high education and mortality inequality (AU)


Assuntos
Humanos , Mortalidade/tendências , Disparidades nos Níveis de Saúde , Escolaridade , Fatores Socioeconômicos , Estatísticas Vitais
5.
Rev Esp Salud Publica ; 89(3): 295-306, 2015.
Artigo em Espanhol | MEDLINE | ID: mdl-26388343

RESUMO

BACKGROUND: Due to the lack of evidence, the objective was to show the inequalities in mortality by educational level in Navarra and the contribution of the main causes of death to the magnitude of inequalities in mortality from all causes of death. METHODS: All citizens aged 25 years and older residing in Spain in 2001 were followed during 7 years to determine their vital status. Level of education was used as socioeconomic status indicator. It was estimated the age-adjusted total mortality rate and mortality rate from cause-specific mortality by educational level. Then it was calculated the relative difference (ratio) and the absolute difference in rates between the lowest and highest levels of education and the contribution of the main causes of death to the absolute difference. RESULTS: The rate ratio for all causes of death was 1.37 in men and 1.23 in women. The human immunodeficiency virus (HIV) (25.84) and unintentional injuries (3.78) are the causes of death with higher rate ratio in men and diabetes (4.92) and HIV (4.38) in women. Cardiovascular diseases were the leading causes of death that contribute most to the absolute difference in mortality: 26% in men and 48% women. CONCLUSIONS: The mortality rate in the Navarre population shows an inverse gradient with educational level, except in some cancer sites. Cardiovascular disease is the leading cause of death that contributes most to the absolute inequalities in mortality, while other causes of death that show significant relative inequalities, contribute little to the absolute inequalities.


Assuntos
Disparidades nos Níveis de Saúde , Mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Causas de Morte , Escolaridade , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Espanha/epidemiologia
6.
Rev. esp. salud pública ; 89(3): 295-306, mayo-jun. 2015. tab
Artigo em Espanhol | IBECS | ID: ibc-138587

RESUMO

Fundamentos: Dada la ausencia de evidencia científica, el objetivo fue mostrar las desigualdades en mortalidad según el nivel de estudios en Navarra y la contribución de las principales causas de defunción a la magnitud de desigualdades en la mortalidad por todas las causas de muerte. Métodos: Todos los ciudadanos de 25 años y mayores residentes en Navarra en 2001 fueron seguidos durante 7 años para conocer su estado vital. El indicador de posición socioeconómica utilizado fue el nivel de estudios. Se estimaron las tasas de mortalidad general y por causa de muerte ajustadas por edad según la educación. Posteriormente, se calcularon la diferencia relativa (razón) y la diferencia absoluta de tasas entre las categorías más baja y más alta de nivel de estudios y la contribución de las principales causas de muerte a la diferencia absoluta. Resultados: La razón de tasas por todas las causas de muerte fue 1,37 en hombres y 1,23 en mujeres. El virus de la inmunodeficiencia humana (VIH) (25,84) y los accidentes no intencionales (3,78) presentaron las razones de tasas más altas en los hombres y la diabetes mellitus (4,92) y el VIH (4,38) en las mujeres. Las enfermedades cardiovasculares constituyeron la causa de muerte que más contribuyó a la diferencia absoluta en mortalidad: 26% en hombres y 48% en mujeres. Conclusiones: La tasa de mortalidad en la población navarra muestra un gradiente inverso con el nivel educativo, a excepción de algunas localizaciones de cáncer. Las enfermedades cardiovasculares son la causa de muerte que más contribuye a las desigualdades absolutas en mortalidad, mientras que otras causas de muerte que muestran importantes desigualdades relativas contribuyen poco a las desigualdades absolutas (AU)


Background: Due to the lack of evidence, the objective was to show the inequalities in mortality by educational level in Navarra and the contribution of the main causes of death to the magnitude of inequalities in mortality from all causes of death. Methods: All citizens aged 25 years and older residing in Spain in 2001 were followed during 7 years to determine their vital status. Level of education was used as socioeconomic status indicator. It was estimated the age-adjusted total mortality rate and mortality rate from cause-specific mortality by educational level. Then it was calculated the relative difference (ratio) and the absolute difference in rates between the lowest and highest levels of education and the contribution of the main causes of death to the absolute difference. Results: The rate ratio for all causes of death was 1.37 in men and 1.23 in women. The human immunodeficiency virus (HIV) (25.84) and unintentional injuries (3.78) are the causes of death with higher rate ratio in men and diabetes (4.92) and HIV (4.38) in women. Cardiovascular diseases were the leading causes of death that contribute most to the absolute difference in mortality: 26% in men and 48% women. Conclusions: The mortality rate in the Navarre population shows an inverse gradient with educational level, except in some cancer sites. Cardiovascular disease is the leading cause of death that contributes most to the absolute inequalities in mortality, while other causes of death that show significant relative inequalities, contribute little to the absolute inequalities (AU)


Assuntos
Feminino , Humanos , Masculino , Disparidades nos Níveis de Saúde , Disparidades nos Níveis de Saúde , Causas de Morte/tendências , Mortalidade/tendências , Estudos Longitudinais , Mortalidade Prematura/tendências , Expectativa de Vida
7.
Rev Esp Salud Publica ; 89(6): 563-73, 2015.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26786304

RESUMO

BACKGROUND: Given the importance of mortality rates in each socioeconomic group, as explanation for the variation in mortality inequalities across populations, the objective of the present study is to evaluate whether regional variation in mortality inequalities in Spain is related to the mortality rates in different socioeconomic groups. METHODS: The study included all persons aged 30-74 years living in Spain in 2001 and followed up for mortality over 7 years. In each of the 17 autonomous communities of Spain mortality rates were estimated for those with low and high education, as well as two measures of mortality inequality according to education: mortality rate difference and mortality rate ratio. Median value of mortality inequalities was calculated for the regions with the highest and lowest mortality rates and for those with intermediate mortality rates. And the Pearson correlation coefficient was used to estimate the relation between mortality rates and the measures of mortality inequality. RESULTS: The correlation coefficients between mortality rate in low education and mortality rate difference and mortality rate ratio were 0.87 and 0.78 in women and 0.81 and 0.73 in men, respectively. The correlation coefficients between mortality rate in high education and mortality rate difference and mortality rate ratio were -0.07 and -0.24 in women and 0.10 and -0.06 in men, respectively. CONCLUSION: Regions with the lowest and highest mortality rates in low education people generally had the lowest and highest inequalities in mortality. The variation in the magnitude of inequalities in mortality from one place to another can be explained by the variation in mortality in low education people. No relation was observed between mortality rate in high education and mortality inequality.


Assuntos
Disparidades nos Níveis de Saúde , Mortalidade , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos , Espanha/epidemiologia
8.
Magn Reson Med ; 73(5): 1764-74, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24806049

RESUMO

PURPOSE: To develop a self-gated alternating repetition time balanced steady-state free precession (ATR-SSFP) pulse sequence for fat-suppressed cardiac cine imaging. METHODS: Cardiac gating is computed retrospectively using acquired magnetic resonance self-gating data, enabling cine imaging without the need for electrocardiogram (ECG) gating. Modification of the slice-select rephasing gradients of an ATR-SSFP sequence enables the acquisition of a one-dimensional self-gating readout during the unused short repetition time (TR). Self-gating readouts are acquired during every TR of segmented, breath-held cardiac scans. A template-matching algorithm is designed to compute cardiac trigger points from the self-gating signals, and these trigger points are used for retrospective cine reconstruction. The proposed approach is compared with ECG-gated ATR-SSFP and balanced steady-state free precession in 10 volunteers and five patients. RESULTS: The difference of ECG and self-gating trigger times has a variability of 13 ± 11 ms (mean ± SD). Qualitative reviewer scoring and ranking indicate no statistically significant differences (P > 0.05) between self-gated and ECG-gated ATR-SSFP images. Quantitative blood-myocardial border sharpness is not significantly different among self-gated ATR-SSFP ( 0.61±0.15 mm -1), ECG-gated ATR-SSFP ( 0.61±0.15 mm -1), or conventional ECG-gated balanced steady-state free precession cine MRI ( 0.59±0.15 mm -1). CONCLUSION: The proposed self-gated ATR-SSFP sequence enables fat-suppressed cardiac cine imaging at 1.5 T without the need for ECG gating and without decreasing the imaging efficiency of ATR-SSFP.


Assuntos
Técnicas de Imagem de Sincronização Cardíaca , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Imagem Cinética por Ressonância Magnética/métodos , Algoritmos , Feminino , Humanos , Masculino , Meglumina/análogos & derivados , Contração Miocárdica/fisiologia , Compostos Organometálicos , Valores de Referência , Sensibilidade e Especificidade
9.
Magn Reson Med ; 71(2): 797-806, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23460510

RESUMO

PURPOSE: Respiratory motion makes hepatic ablation using high intensity focused ultrasound (HIFO) challenging. Previous HIFU liver treatment had required apnea induced during general anesthesia. We describe and test a system that allows treatment of the liver in the presence of breathing motion. METHODS: Mapping a signal from an external respiratory bellow to treatment locations within the liver allows the ultrasound transducer to be steered in real time to the target location. Using a moving phantom, three metrics were used to compare static, steered, and unsteered sonications: the area of sonications once a temperature rise of 15°C was achieved, the energy deposition required to reach that temperature, and the average rate of temperature rise during the first 10 s of sonication. Steered HIFU in vivo ablations of the porcine liver were also performed and compared to breath-hold ablations. RESULTS: For the last phantom metric, all groups were found to be statistically significantly different (P ≤ 0.003). However, in the other two metrics, the static and unsteered sonications were not statistically different (P > 0.9999). Steered in vivo HIFU ablations were not statistically significantly different from ablations during breath-holding. CONCLUSIONS: A system for performing HIFU steering during ablation of the liver with breathing motion is presented and shown to achieve results equivalent to ablation performed with breath-holding.


Assuntos
Artefatos , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Fígado/cirurgia , Imageamento por Ressonância Magnética/métodos , Técnicas de Imagem de Sincronização Respiratória/métodos , Cirurgia Assistida por Computador/métodos , Animais , Desenho de Equipamento , Análise de Falha de Equipamento , Hepatectomia/instrumentação , Hepatectomia/métodos , Ablação por Ultrassom Focalizado de Alta Intensidade/instrumentação , Fígado/patologia , Imageamento por Ressonância Magnética/instrumentação , Imagens de Fantasmas , Mecânica Respiratória , Técnicas de Imagem de Sincronização Respiratória/instrumentação , Cirurgia Assistida por Computador/instrumentação , Suínos , Resultado do Tratamento
10.
Neurocase ; 20(3): 273-82, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23819463

RESUMO

Tactile vision has been approached from a variety of angles using different techniques. So far, a certain kind of object (and text) recognition has been shown, though seeing as such has not been achieved yet, and it remains unclear. Trough repetitive passive tactile stimulation perceptual processing is transferred from temporo-parietal to occipital areas, which affects object recognition. We report the results of passive tactile stimulation, as well as rTMS, applied to a 50 year old left handed blind male with over 97% loss of vision, who suffers from Peter's anomaly and microphthalmia. After 15 weeks of passive tactile stimulation, the subject showed increased activity in occipital areas associated with the development of visual-like perception which remained unchanged after three months without passive tactile stimulation. Inhibitory rTMS over the visual cortex led to noticeable reduction of spatial recognition performance and visual sensations in this subject. Stable changes in occipital cortical activity can be associated with subjective sensations of seeing. Once occipital activation has been achieved, it is necessary for spatial object recognition. Both facts highlight the implication of occipital areas in tactile vision and the cortical plasticity of passive tactile long-term stimulation in people with blindness.


Assuntos
Cegueira/fisiopatologia , Lobo Occipital/fisiopatologia , Reconhecimento Psicológico/fisiologia , Percepção do Tato/fisiologia , Percepção Visual/fisiologia , Eletroencefalografia , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Física , Estimulação Magnética Transcraniana
11.
Rev Neurol ; 56 Suppl 1: S163-9, 2013 Feb 22.
Artigo em Espanhol | MEDLINE | ID: mdl-23446719

RESUMO

Cortical reorganization after congenital blindness is not sufficiently known yet it does offer an optimum window of opportunity to study the effects of absolute sensorial deprivation. Cross-modality in people with blindness has been documented, but it may differ in congenital blindness and in early blindness. Vibrotactile passive stimulation of lines and letters generates different electroencephalographic patterns with different source localizations in two children with blindness, aged 9 and 10, respectively with congenital blindness and early blindness with some remnants of vision. Most of the brain electrical activity is centered in auditive areas in P50 and P100 in the case of the child with congenital blindness, while the other shows activity in multiple areas. Reaction times to letters are shorter than to lines of different orientation in both children.


Assuntos
Cegueira/congênito , Cegueira/fisiopatologia , Encéfalo/crescimento & desenvolvimento , Percepção Espacial/fisiologia , Tato/fisiologia , Criança , Feminino , Humanos , Masculino , Projetos Piloto
12.
Rev. neurol. (Ed. impr.) ; 56(supl.1): S163-S169, 22 feb., 2013. ilus, graf
Artigo em Espanhol | IBECS | ID: ibc-111696

RESUMO

La reorganización cortical subyacente a la ceguera congénita no se conoce suficientemente, pero esta última ofrece una ventana óptima para el estudio de los efectos de la deprivación sensorial absoluta. Se sabe también que existe cross-modality en el cerebro de los invidentes, pero ésta difiere en niños con ceguera congénita y aquellos otros con restos de visión. La estimulación vibrotáctil pasiva de líneas y letras genera patrones electroencefalográficos y de localización de fuentes distintos en dos niños de 9 y 10 años, respectivamente, con ceguera congénita y ceguera con restos de visión. En la niña con ceguera congénita, la mayor actividad eléctrica cortical se centra en áreas auditivas en P50 y P100, mientras que en el niño invidente con restos de visión, la actividad se distribuye en múltiples áreas. Los tiempos de reacción a las letras son menores que a las líneas de diferente orientación en ambos niños (AU)


Cortical reorganization after congenital blindness is not sufficiently known yet it does offer an optimum window of opportunity to study the effects of absolute sensorial deprivation. Cross-modality in people with blindness has been documented, but it may differ in congenital blindness and in early blindness. Vibrotactile passive stimulation of lines and letters generates different electroencephalographic patterns with different source localizations in two children with blindness, aged 9 and 10, respectively with congenital blindness and early blindness with some remnants of vision. Most of the brain electrical activity is centered in auditive areas in P50 and P100 in the case of the child with congenital blindness, while the other shows activity in multiple areas. Reaction times to letters are shorter than to lines of different orientation in both children (AU)


Assuntos
Humanos , Masculino , Feminino , Criança , Cegueira/fisiopatologia , Percepção Espacial/fisiologia , Processos Mentais , Córtex Cerebral/fisiologia , Córtex Somatossensorial/fisiologia , Distúrbios Somatossensoriais/diagnóstico
13.
Magn Reson Med ; 69(3): 839-44, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22556062

RESUMO

Three-dimensional cardiac magnetic resonance perfusion imaging is promising for the precise sizing of defects and for providing high perfusion contrast, but remains an experimental approach primarily due to the need for large-dimensional encoding, which, for traditional 3DFT imaging, requires either impractical acceleration factors or sacrifices in spatial resolution. We demonstrated the feasibility of rapid three-dimensional cardiac magnetic resonance perfusion imaging using a stack-of-spirals acquisition accelerated by non-Cartesian k-t SENSE, which enables entire myocardial coverage with an in-plane resolution of 2.4 mm. The optimal undersampling pattern was used to achieve the largest separation between true and aliased signals, which is a prerequisite for k-t SENSE reconstruction. Flip angle and saturation recovery time were chosen to ensure negligible magnetization variation during the transient data acquisition. We compared the proposed three-dimensional perfusion method with the standard 2DFT approach by consecutively acquiring both data during each R-R interval in cardiac patients. The mean and standard deviation of the correlation coefficients between time intensity curves of three-dimensional versus 2DFT were 0.94 and 0.06 across seven subjects. The linear correlation between the two sets of upslope values was significant (r = 0.78, P < 0.05).


Assuntos
Algoritmos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Angiografia por Ressonância Magnética/métodos , Imagem de Perfusão do Miocárdio/métodos , Humanos , Aumento da Imagem/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
Am J Emerg Med ; 30(9): 1943-9, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22795427

RESUMO

PURPOSES: Emergency physician-performed ultrasonography holds promise as a rapid and accurate method to diagnose multiple diseases in the emergency department (ED). Our objective was to assess the initial diagnostic accuracy (first 55 explorations) of emergency physician-performed ultrasonography for multiple categories of ultrasound use after a short training period. BASIC PROCEDURES: This was a prospective observational study conducted at an urban ED from June 2010 to March 2011 in patients with suspected cholecystitis, hydronephrosis, deep vein thrombosis, and different cardiovascular problems. Five physicians had a 10-hour training session before enrolling patients. The test characteristics of bedside ultrasonography were determined with the final radiologist/cardiologist interpretation. MAIN FINDINGS: A total of 275 ultrasonographic examinations were performed (78 abdominal explorations, 80 renal explorations, 76 2-point compression ultrasonographic examinations in patients with suspected deep vein thrombosis, and 41 echocardiograms in patients with different acute cardiovascular problems). Radiologists/cardiologists detected 28 cases of cholecystitis, 26 cases of deep vein thrombosis, 49 cases of hydronephrosis, and 15 cases of significant cardiovascular alterations. The overall diagnostic accuracy of ED ultrasonograms yielded a sensitivity, specificity, positive predictive value, and negative predictive value of 92.6% (95% confidence interval [CI], 90%-99%), 89% (95% CI, 84%-94%), 86.2 % (95% CI, 82%-93%), and 94.2% (95% CI, 92%-99%), respectively. Nineteen (6.9%) false-positive results and 6 false-negative results (2.1%) were obtained. PRINCIPAL CONCLUSIONS: Emergency physicians in our institution attained reasonably high initial accuracy in the performance of ultrasonography for a variety of clinical problems after a 10-hour training period.


Assuntos
Serviço Hospitalar de Emergência , Sistemas Automatizados de Assistência Junto ao Leito , Ultrassonografia , Idoso , Doenças Cardiovasculares/diagnóstico por imagem , Colecistite/diagnóstico por imagem , Serviço Hospitalar de Emergência/normas , Feminino , Humanos , Hidronefrose/diagnóstico por imagem , Masculino , Estudos Prospectivos , Trombose Venosa/diagnóstico por imagem
15.
Rev Neurol ; 54 Suppl 1: S137-45, 2012 Feb 29.
Artigo em Espanhol | MEDLINE | ID: mdl-22374766

RESUMO

INTRODUCTION: Several studies have enhanced differences and similarities in the processing of early and late acquired languages. Anatomic and functional differences have demonstrated how bilingualism exerts executive functions, dependent of the prefrontal cortex in the frontal lobe. AIM: To study the cortical differences, neurophysiologically measured in school-aged children, in the processing of known and unknown languages. SUBJECTS AND METHODS: We have measured the recognition processes of words in several languages, specifically Spanish, English, Portuguese and Mandarin Chinese, as well as their event-related potentials (ERP) correlates in 10 year-old children. RESULTS: The greater knowledge of a language (in our study, Spanish) associates shorter latencies in ERP and a greater activity in both early (N200) and late (N400) components of temporal regions, demonstrating both a direct relation between practice and speed of processing of the language and the consolidation of the linguistic information in the temporal lobe, while less familiar or unknown languages show longer latencies and a greater involvement of posterior brain areas, as well as a different lateralization probably due to a higher effort put on its integration, mostly in late processing stages of linguistic information, which ultimately reflects a clear effect of the neuroplasticity generated by practice, as more efficient and stable neural networks are created after being trained for a long time, in contrast with what occurs with those which have not been sufficiently stimulated. CONCLUSION: Mandarin Chinese's organization in the brain cortex shows bilateral with right dominant lateralization as well as longer ERP latencies.


Assuntos
Mapeamento Encefálico , Córtex Cerebral/fisiologia , Potenciais Evocados Auditivos/fisiologia , Função Executiva/fisiologia , Idioma , Multilinguismo , Criança , Dominância Cerebral , Eletroculografia , Feminino , Humanos , Masculino , Plasticidade Neuronal , Lobo Occipital/fisiologia , Lobo Parietal/fisiologia , Prática Psicológica , Tempo de Reação , Reconhecimento Psicológico/fisiologia , Lobo Temporal/fisiologia
16.
Magn Reson Med ; 68(6): 1876-85, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22457248

RESUMO

When evaluating the severity of valvular stenosis, the peak velocity of the blood flow is routinely used to estimate the transvalvular pressure gradient. One-dimensional Fourier velocity encoding effectively detects the peak velocity with an ungated time series of spatially resolved velocity spectra in real time. However, measurement accuracy can be degraded by the pulsatile and turbulent nature of stenotic flow and the existence of spatially varying off-resonance. In this work, we investigate the feasibility of improving the peak velocity detection capability of one-dimensional Fourier velocity encoding for stenotic flow using a novel echo-shifted interleaved readout combined with a variable-density circular k-space trajectory. The shorter echo and readout times of the echo-shifted interleaved acquisitions are designed to reduce sensitivity to off-resonance. Preliminary results from limited phantom and in vivo results also indicate that some artifacts from pulsatile flow appear to be suppressed when using this trajectory compared to conventional single-shot readouts, suggesting that peak velocity detection may be improved. The efficiency of the new trajectory improves the temporal and spatial resolutions. To realize the proposed readout, a novel multipoint-traversing algorithm is introduced for flexible and automated gradient-waveform design.


Assuntos
Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/fisiopatologia , Artefatos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Angiografia por Ressonância Magnética/métodos , Imagem de Perfusão do Miocárdio/métodos , Algoritmos , Velocidade do Fluxo Sanguíneo , Análise de Fourier , Humanos , Fluxo Pulsátil , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Rev. neurol. (Ed. impr.) ; 54(supl.1): s137-s145, 29 feb., 2012. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-99626

RESUMO

Introducción. Diversos estudios han resaltado las diferencias y similitudes en el procesamiento de las lenguas maternas y las aprendidas con posterioridad. Se han encontrado diferencias anatómicas y funcionales que indican cómo el bilingüismo permite ejercitar unas habilidades ejecutivas fundamentales en nuestra vida diaria y dependientes del lóbulo frontal. Objetivo. Estudiar las diferencias cerebrales, medidas neurofisiológicamente en niños en edad escolar, en el procesamiento de lenguas conocidas y no conocidas. Sujetos y métodos. Se realizaron mediciones de reconocimiento de palabras en varios idiomas, conocidos y no conocidos (específicamente español, inglés, portugués y chino mandarín), así como de sus correlatos en potenciales evocados, a niños de 10 años. Resultados. La lengua materna (en este caso el español) se asocia con latencias más cortas en los potenciales evocados y una mayor actividad tanto en componentes tempranos (N200) como en tardíos (N400) de áreas temporales, señalando una relación entre el grado de práctica y la velocidad de procesamiento del idioma, así como una consolidación de la información lingüística. En las lenguas menos conocidas existe una mayor latencia y una mayor implicación de estructuras cerebrales posteriores extratemporales y una diferente lateralización, probablemente debido a un mayor esfuerzo en su integración, sobre todo en el procesamiento tardío de la información lingüística, lo que, en su conjunto, refleja un claro efecto de la neuroplasticidad generada asociada a la práctica, ya que se crean unas redes neuronales más estables y eficientes tras ser entrenadas durante mucho tiempo, a diferencia de aquéllas que han sido poco estimuladas. Conclusión. Asimismo, se detecta, en la organización cerebral del mandarín, una mayor implicación bilateral de áreas posteriores temporoparietales con predomino derecho (AU)


Introduction. Several studies have enhanced differences and similarities in the processing of early and late acquired languages. Anatomic and functional differences have demonstrated how bilingualism exerts executive functions, dependent of the prefrontal cortex in the frontal lobe. Aim. To study the cortical differences, neurophysiologically measured in school-aged children, in the processing of known and unknown languages. Subjects and methods. We have measured the recognition processes of words in several languages, specifically Spanish, English, Portuguese and Mandarin Chinese, as well as their event-related potentials (ERP) correlates in 10 year-old children. Results. The greater knowledge of a language (in our study, Spanish) associates shorter latencies in ERP and a greater activity in both early (N200) and late (N400) components of temporal regions, demonstrating both a direct relation between practice and speed of processing of the language and the consolidation of the linguistic information in the temporal lobe, while less familiar or unknown languages show longer latencies and a greater involvement of posterior brain areas, as well as a different lateralization probably due to a higher effort put on its integration, mostly in late processing stages of linguistic information, which ultimately reflects a clear effect of the neuroplasticity generated by practice, as more efficient and stable neural networks are created after being trained for a long time, in contrast with what occurs with those which have not been sufficiently stimulated. Conclusion. Mandarin Chinese’s organization in the brain cortex shows bilateral with right dominant lateralization as well as longer ERP latencies (AU)


Assuntos
Humanos , Córtex Cerebral/fisiologia , Processos Mentais/fisiologia , Aprendizagem/fisiologia , Desenvolvimento da Linguagem , Multilinguismo , Potenciais Evocados
18.
IEEE Trans Med Imaging ; 31(2): 370-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21954200

RESUMO

Magnetic resonance imaging (MRI) pulse sequence consoles typically employ closed proprietary hardware, software, and interfaces, making difficult any adaptation for innovative experimental technology. Yet MRI systems research is trending to higher channel count receivers, transmitters, gradient/shims, and unique interfaces for interventional applications. Customized console designs are now feasible for researchers with modern electronic components, but high data rates, synchronization, scalability, and cost present important challenges. Implementing large multichannel MR systems with efficiency and flexibility requires a scalable modular architecture. With Medusa, we propose an open system architecture using the universal serial bus (USB) for scalability, combined with distributed processing and buffering to address the high data rates and strict synchronization required by multichannel MRI. Medusa uses a modular design concept based on digital synthesizer, receiver, and gradient blocks, in conjunction with fast programmable logic for sampling and synchronization. Medusa is a form of synthetic instrument, being reconfigurable for a variety of medical/scientific instrumentation needs. The Medusa distributed architecture, scalability, and data bandwidth limits are presented, and its flexibility is demonstrated in a variety of novel MRI applications.


Assuntos
Redes de Comunicação de Computadores/instrumentação , Interpretação de Imagem Assistida por Computador/instrumentação , Imageamento por Ressonância Magnética/instrumentação , Magnetismo/instrumentação , Processamento de Sinais Assistido por Computador/instrumentação , Software , Transdutores , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
19.
Med Phys ; 38(9): 5081-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21978053

RESUMO

PURPOSE: High intensity focused ultrasound (HIFU) in the abdomen can be sensitive to acoustic aberrations that can exist in the beam path of a single sonication. Having an accurate method to quickly visualize the transducer focus without damaging tissue could assist with executing the treatment plan accurately and predicting these changes and obstacles. By identifying these obstacles, MR acoustic radiation force imaging (MR-ARFI) provides a reliable method for visualizing the transducer focus quickly without damaging tissue and allows accurate execution of the treatment plan. METHODS: MR-ARFI was used to view the HIFU focus, using a gated spin echo flyback readout-segmented echo-planar imaging sequence. HIFU spots in a phantom and in the livers of five live pigs under general anesthesia were created with a 550 kHz extracorporeal phased array transducer initially localized with a phase-dithered MR-tracking sequence to locate microcoils embedded in the transducer. MR-ARFI spots were visualized, observing the change of focal displacement and ease of steering. Finally, MR-ARFI was implemented as the principle liver HIFU calibration system, and MR-ARFI measurements of the focal location relative to the thermal ablation location in breath-hold and breathing experiments were performed. RESULTS: Measuring focal displacement with MR-ARFI was achieved in the phantom and in vivo liver. In one in vivo experiment, where MR-ARFI images were acquired repeatedly at the same location with different powers, the displacement had a linear relationship with power [y = 0.04x + 0.83 µm (R(2) = 0.96)]. In another experiment, the displacement images depicted the electronic steering of the focus inside the liver. With the new calibration system, the target focal location before thermal ablation was successfully verified. The entire calibration protocol delivered 20.2 J of energy to the animal (compared to greater than 800 J for a test thermal ablation). ARFI displacement maps were compared with thermal ablations during seven breath-hold ablations. The error was 0.83 ± 0.38 mm in the S/I direction and 0.99 ± 0.45 mm in the L/R direction. For six spots in breathing ablations, the mean error in the nonrespiration direction was 1.02 ± 0.89 mm. CONCLUSIONS: MR-ARFI has the potential to improve free-breathing plan execution accuracy compared to current calibration and acoustic beam adjustment practices. Gating the acquisition allows for visualization of the focal spot over the course of respiratory motion, while also being insensitive to motion effects that can complicate a thermal test spot. That MR-ARFI measures a mechanical property at the focus also makes it insensitive to high perfusion, of particular importance to highly perfused organs such as the liver.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Suínos , Animais , Calibragem , Imagens de Fantasmas , Respiração , Termômetros
20.
PLoS One ; 6(8): e23264, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21853098

RESUMO

Over three months of intensive training with a tactile stimulation device, 18 blind and 10 blindfolded seeing subjects improved in their ability to identify geometric figures by touch. Seven blind subjects spontaneously reported 'visual qualia', the subjective sensation of seeing flashes of light congruent with tactile stimuli. In the latter subjects tactile stimulation evoked activation of occipital cortex on electroencephalography (EEG). None of the blind subjects who failed to experience visual qualia, despite identical tactile stimulation training, showed EEG recruitment of occipital cortex. None of the blindfolded seeing humans reported visual-like sensations during tactile stimulation. These findings support the notion that the conscious experience of seeing is linked to the activation of occipital brain regions in people with blindness. Moreover, the findings indicate that provision of visual information can be achieved through non-visual sensory modalities which may help to minimize the disability of blind individuals, affording them some degree of object recognition and navigation aid.


Assuntos
Cegueira/fisiopatologia , Lobo Occipital/fisiopatologia , Sensação/fisiologia , Visão Ocular/fisiologia , Adolescente , Adulto , Idoso , Comportamento/fisiologia , Eletrodos , Potenciais Evocados/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Reação/fisiologia , Análise de Regressão , Adulto Jovem
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