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1.
Gac Sanit ; 29 Suppl 1: 60-5, 2015 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-26342414

RESUMO

OBJECTIVE: To identify factors that people with a traumatic brain injury and their families perceived as helping to improve their quality of life. METHODS: Three focus groups and five interviews were conducted with a total of 37 participants: 14 persons with traumatic brain injury and 23 caregivers. A content analysis was conducted. The constant comparative method was applied. RESULTS: We detected five factors that improved the quality of life of persons with a traumatic brain and their families: 1) Informal support (family and friends); 2) formal support (counseling, employment, built and bureaucratic environment); 3) type of clinical characteristics; 4) social participation, and 5) social visibility. CONCLUSIONS: The needs expressed by our participants primarily focused on social and emotional factors. For persons with severe traumatic brain injury attempting to achieve the best possible community integration, a new semiology is required, not limited to medical care, but also involving social and psychological care tailored to the needs of each individual and family and their environment.


Assuntos
Acidentes de Trânsito/psicologia , Lesões Encefálicas Traumáticas/psicologia , Adulto , Idoso , Lesões Encefálicas Traumáticas/etiologia , Lesões Encefálicas Traumáticas/reabilitação , Transtornos da Comunicação/etiologia , Transtornos da Comunicação/psicologia , Transtornos da Comunicação/reabilitação , Emoções , Características da Família , Feminino , Grupos Focais , Humanos , Masculino , Transtornos Mentais/etiologia , Transtornos Mentais/psicologia , Transtornos Mentais/reabilitação , Pessoa de Meia-Idade , Distância Psicológica , Qualidade de Vida , Participação Social , Apoio Social
2.
Gac. sanit. (Barc., Ed. impr.) ; 29(supl.1): 60-65, sept. 2015. tab
Artigo em Espanhol | IBECS | ID: ibc-149766

RESUMO

Objetivo: Identificar los factores que las personas con traumatismo craneoencefálico (TCE) y sus familias perciben que contribuyen a mejorar su calidad de vida. Métodos: Se realizaron tres grupos focales y cinco entrevistas, con un total de 37 participantes: 14 personas con TCE y 23 familiares. Se realizó un análisis de contenido. Se aplicó el método de comparaciones constantes. Resultados: Tanto para las personas con TCE por accidente de tráfico como para sus familias se detectan cinco factores principales que mejoran su calidad de vida: 1) apoyo informal (familia y amigos); 2) apoyo formal (apoyo psicológico, inserción laboral, entorno construido y burocrático); 3) tipo de secuelas; 4) participación y 5) visibilización social. Conclusiones: Las necesidades expresadas por los participantes se centran sobre todo en aspectos sociales y emocionales. Para las personas con TCE y sus familias, que tratan de lograr la mejor integración posible en la comunidad, se requiere una nueva semiología, no sólo limitada a la atención médica sino también en materia de asistencia social y psicológica, que se adapte a las necesidades de cada familia y del contexto (AU)


Objective: To identify factors that people with a traumatic brain injury and their families perceived as helping to improve their quality of life. Methods: Three focus groups and five interviews were conducted with a total of 37 participants: 14 persons with traumatic brain injury and 23 caregivers. A content analysis was conducted. The constant comparative method was applied. Results: We detected five factors that improved the quality of life of persons with a traumatic brain and their families: 1) Informal support (family and friends); 2) formal support (counseling, employment, built and bureaucratic environment); 3) type of clinical characteristics; 4) social participation, and 5) social visibility. Conclusions: The needs expressed by our participants primarily focused on social and emotional factors. For persons with severe traumatic brain injury attempting to achieve the best possible community integration, a new semiology is required, not limited to medical care, but also involving social and psychological care tailored to the needs of each individual and family and their environment (AU)


Assuntos
Humanos , Acidentes de Trânsito/estatística & dados numéricos , Traumatismo Múltiplo/psicologia , Traumatismos Craniocerebrais/psicologia , Apoio Social , Impacto Psicossocial , Avaliação das Necessidades , Qualidade de Vida , Perfil de Impacto da Doença , Relações Familiares , 25783
3.
IEEE J Biomed Health Inform ; 19(1): 124-31, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25204001

RESUMO

Cognitive rehabilitation aims to remediate or alleviate the cognitive deficits appearing after an episode of acquired brain injury (ABI). The purpose of this work is to describe the telerehabilitation platform called Guttmann Neuropersonal Trainer (GNPT) which provides new strategies for cognitive rehabilitation, improving efficiency and access to treatments, and to increase knowledge generation from the process. A cognitive rehabilitation process has been modeled to design and develop the system, which allows neuropsychologists to configure and schedule rehabilitation sessions, consisting of set of personalized computerized cognitive exercises grounded on neuroscience and plasticity principles. It provides remote continuous monitoring of patient's performance, by an asynchronous communication strategy. An automatic knowledge extraction method has been used to implement a decision support system, improving treatment customization. GNPT has been implemented in 27 rehabilitation centers and in 83 patients' homes, facilitating the access to the treatment. In total, 1660 patients have been treated. Usability and cost analysis methodologies have been applied to measure the efficiency in real clinical environments. The usability evaluation reveals a system usability score higher than 70 for all target users. The cost efficiency study results show a relation of 1-20 compared to face-to-face rehabilitation. GNPT enables brain-damaged patients to continue and further extend rehabilitation beyond the hospital, improving the efficiency of the rehabilitation process. It allows customized therapeutic plans, providing information to further development of clinical practice guidelines.


Assuntos
Lesões Encefálicas/reabilitação , Transtornos Cognitivos/reabilitação , Terapia Cognitivo-Comportamental/métodos , Sistemas de Apoio a Decisões Clínicas/organização & administração , Assistência Centrada no Paciente/métodos , Telemedicina/métodos , Adolescente , Adulto , Lesões Encefálicas/diagnóstico , Lesões Encefálicas/economia , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/economia , Terapia Cognitivo-Comportamental/economia , Sistemas de Apoio a Decisões Clínicas/economia , Feminino , Custos de Cuidados de Saúde/estatística & dados numéricos , Humanos , Masculino , Assistência Centrada no Paciente/economia , Espanha , Telemedicina/economia , Terapia Assistida por Computador , Resultado do Tratamento , Interface Usuário-Computador , Adulto Jovem
4.
J Neurotrauma ; 30(23): 1991-4, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23822854

RESUMO

Signal-intensity contrast of T1-weighted magnetic resonance imaging scans has been associated with tissue integrity and reported as a sign of neurodegenerative changes in diseases such as Alzheimer's disease. After severe traumatic brain injury (TBI), progressive structural changes occur in white (WM) and gray matter (GM). In the current study, we assessed the signal-intensity contrast of GM and WM in patients with diffuse TBI in the chronic stage to (1) characterize the regional pattern of WM/GM changes in intensity contrast associated with traumatic axonal injury, (2) evaluate possible associations between this measure and diffusion tensor image (DTI)/fractional anisotropy (FA) for detecting WM damage, and (3) investigate the correlates of both measures with cognitive outcomes. Structural T1 scans were processed with FreeSurfer software to identify the boundary and calculate the WM/GM contrast maps. DTIs were processed with the FMRIB software library to obtain FA maps. The WM/GM contrast in TBI patients showed a pattern of reduction in almost all of the brain, except the visual and motor primary regions. Global FA values obtained from DTI correlated with the intensity contrast of all associative cerebral regions. WM/GM contrast correlated with memory functions, whereas FA global values correlated with tests measuring memory and mental processing speed. In conclusion, tissue-contrast intensity is a very sensitive measure for detecting structural brain damage in chronic, severe and diffuse TBI, but is less sensitive than FA for reflecting neuropsychological sequelae, such as impaired mental processing speed.


Assuntos
Lesões Encefálicas/patologia , Encéfalo/patologia , Adulto , Lesões Encefálicas/complicações , Lesões Encefálicas/psicologia , Doença Crônica , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/psicologia , Imagem de Tensor de Difusão , Feminino , Escala de Coma de Glasgow , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Testes Neuropsicológicos , Adulto Jovem
5.
JAMA Neurol ; 70(7): 845-51, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23689958

RESUMO

IMPORTANCE: The study of brain activity and connectivity at rest provides a unique opportunity for the investigation of the brain substrates of cognitive outcome after traumatic axonal injury. This knowledge may contribute to improve clinical management and rehabilitation programs. OBJECTIVE: To study functional magnetic resonance imaging abnormalities in signal amplitude and brain connectivity at rest and their relationship to cognitive outcome in patients with chronic and severe traumatic axonal injury. DESIGN: Observational study. SETTING: University of Barcelona and Hospital Clinic de Barcelona, Barcelona, and Institut Guttmann-Neurorehabilitation Hospital, Badalona, Spain. PARTICIPANTS: Twenty patients with traumatic brain injury (TBI) were studied, along with 17 matched healthy volunteers. INTERVENTIONS: Resting-state functional magnetic resonance imaging and diffusion tensor imaging data were acquired. After exploring group differences in amplitude of low-frequency fluctuations (ALFF), we studied functional connectivity within the default mode network (DMN) by means of independent component analysis, followed by a dual regression approach and seed-based connectivity analyses. Finally, we performed probabilistic tractography between the frontal and posterior nodes of the DMN. MAIN OUTCOMES AND MEASURES: Signal amplitude and functional connectivity during the resting state, tractography related to DMN, and the association between signal amplitudes and cognitive outcome. RESULTS: Patients had greater ALFF in frontal regions, which was correlated with cognitive performance. Within the DMN, patients showed increased connectivity in the frontal lobes. Seed-based connectivity analyses revealed augmented connectivity within surrounding areas of the frontal and left parietal nodes of the DMN. Fractional anisotropy of the cingulate tract was correlated with increased connectivity of the frontal node of the DMN in patients with TBI. CONCLUSIONS AND RELEVANCE: Increased ALFF is related to better cognitive performance in chronic TBI. The loss of structural connectivity produced by damage to the cingulum tract explained the compensatory increases in functional connectivity within the frontal node of the DMN.


Assuntos
Lesões Encefálicas/patologia , Córtex Cerebral/patologia , Imagem de Tensor de Difusão/métodos , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/patologia , Adulto , Anisotropia , Lesões Encefálicas/fisiopatologia , Córtex Cerebral/fisiopatologia , Lesão Axonal Difusa/patologia , Lesão Axonal Difusa/fisiopatologia , Imagem de Tensor de Difusão/instrumentação , Feminino , Lobo Frontal/patologia , Lobo Frontal/fisiopatologia , Giro do Cíngulo/patologia , Giro do Cíngulo/fisiopatologia , Humanos , Imageamento por Ressonância Magnética/instrumentação , Masculino , Rede Nervosa/fisiopatologia , Testes Neuropsicológicos , Lobo Parietal/patologia , Lobo Parietal/fisiopatologia , Adulto Jovem
6.
Cortex ; 49(3): 646-57, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22482692

RESUMO

We investigated structural brain damage in subjects who had suffered severe and diffuse traumatic brain injury (TBI), and examined its relationship with declarative memory impairment. Cortical thickness, diffusion tensor imaging (DTI), and volumetric and shape data of the hippocampus were assessed in a group of 26 adults with severe TBI in the chronic stage and 22 healthy matched controls. Declarative memory was evaluated by Rey's Auditory Verbal Learning Test (RAVLT). TBI patients performed significantly worse than controls on all RAVLT measures. The group comparison for cortical thickness and DTI revealed a pattern of widespread atrophy in TBI patients. In the TBI group DTI measures correlated with cortical thickness in the prefrontal and parietal regions, including the precuneus. Declarative memory correlated with both cortical thickness and DTI measures. However, although hippocampal volume was significantly decreased in TBI patients, no correlations were found. Multiple regression analysis of all the structural measures revealed that decreases in Fractional anisotropy (FA) and thinning of the left parietal region were the best predictors of memory impairment. In conclusion, cortical thickness reductions in the left hemisphere and a lack of white matter integrity are the main contributors to long-term impairment in declarative memory among patients suffering from severe and diffuse TBI. In this study the hippocampus did not make a significant contribution to memory dysfunctions, suggesting that damage to this structure is compensated for by other regions, with the definitive sequelae being mainly explained by alterations in cortico-subcortical connectivity.


Assuntos
Lesões Encefálicas/psicologia , Córtex Cerebral/patologia , Hipocampo/patologia , Transtornos da Memória/psicologia , Fibras Nervosas Mielinizadas/patologia , Adulto , Atrofia/complicações , Atrofia/patologia , Atrofia/fisiopatologia , Lesões Encefálicas/complicações , Lesões Encefálicas/patologia , Mapeamento Encefálico , Córtex Cerebral/fisiopatologia , Imagem de Tensor de Difusão , Feminino , Hipocampo/fisiopatologia , Humanos , Masculino , Memória/fisiologia , Transtornos da Memória/etiologia , Transtornos da Memória/patologia , Transtornos da Memória/fisiopatologia , Testes Neuropsicológicos , Tamanho do Órgão , Aprendizagem Verbal/fisiologia
7.
PLoS One ; 8(12): e83598, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24386232

RESUMO

Rehabilitation can improve cognitive deficits observed in patients with traumatic brain injury (TBI). However, despite rehabilitation, the ability of making a choice often remains impaired. Risk taking is a daily activity involving numerous cognitive processes subserved by a complex neural network. In this work we investigated risk taking using the Balloon Analogue Risk Task (BART) in patients with acute TBI and healthy controls. We hypothesized that individuals with TBI will take less risk at the BART as compared to healthy individuals. We also predicted that within the TBI group factors such as the number of days since the injury, severity of the injury, and sites of the lesion will play a role in risk taking as assessed with the BART. Main findings revealed that participants with TBI displayed abnormally cautious risk taking at the BART as compared to healthy subjects. Moreover, healthy individuals showed increased risk taking throughout the task which is in line with previous work. However, individuals with TBI did not show this increased risk taking during the task. We also investigated the influence of three patients' characteristics on their performance at the BART: Number of days post injury, Severity of the head injury, and Status of the frontal lobe. Results indicate that performance at the BART was influenced by the number of days post injury and the status of the frontal lobe, but not by the severity of the head injury. Reported findings are encouraging for risk taking seems to naturally improve with time postinjury. They support the need of conducting longitudinal prospective studies to ultimately identify impaired and intact cognitive skills that should be trained postinjury.


Assuntos
Lesões Encefálicas/reabilitação , Hospitalização , Assunção de Riscos , Adulto , Análise de Variância , Estudos de Casos e Controles , Comportamento de Escolha , Feminino , Lobo Frontal/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Índice de Gravidade de Doença , Fatores de Tempo , Adulto Jovem
8.
Eur J Pharmacol ; 659(2-3): 259-64, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21463624

RESUMO

Fructose 1,6 biphosphate (F1,6BP) exerts a protective effect in several in vitro models of induced injury and in isolated organs; however, few studies have been performed using in vivo hypothermia. Here we studied the effects of deep hypothermia (21ºC) and rewarming in anaesthetised rats after F1,6BP administration (2 g/kg body weight). Acid-base and oxidative stress parameters (plasma malondialdehyde and glutathione, and erythrocyte antioxidant enzymes) were evaluated. Erythrocyte and leukocyte numbers in blood and plasma nitric oxide were also measured 3 h after F1,6BP administration in normothermia animals. In the absence of F1,6BP metabolic acidosis developed after rewarming. Oxidative stress was also evident after rewarming, as shown by a decrease in thiol groups and in erythrocyte superoxide dismutase, catalase and GSH-peroxidase, which corresponded to an increase in AST in rewarmed animals. These effects were reverted in rats treated with F1,6BP. Blood samples of F1,6BP-treated animals showed a significant increase in plasma nitric oxide 3 h after administration, coinciding with a significant rise in leukocyte number. F1,6BP protection may be due to the decrease in oxidative stress and to the preservation of the antioxidant pool. In addition, we propose that the reduction in extracellular acidosis may be due to improved tissue perfusion during rewarming and that nitric oxide may play a central role.


Assuntos
Acidose/etiologia , Acidose/prevenção & controle , Frutosedifosfatos/administração & dosagem , Frutosedifosfatos/farmacologia , Hipotermia/complicações , Estresse Oxidativo/efeitos dos fármacos , Reaquecimento/efeitos adversos , Acidose/metabolismo , Acidose/fisiopatologia , Animais , Óxido Nítrico/biossíntese , Óxido Nítrico/metabolismo , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Vasodilatação/efeitos dos fármacos
9.
BMC Neurol ; 11: 24, 2011 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-21345223

RESUMO

BACKGROUND: Memory is one of the most impaired functions after traumatic brain injury (TBI). We used diffusion tensor imaging (DTI) to determine the structural basis of memory deficit. We correlated fractional anisotropy (FA) of the fasciculi connecting the main cerebral regions that are involved in declarative and working memory functions. METHODS: Fifteen patients with severe and diffuse TBI and sixteen healthy controls matched by age and years of education were scanned. The neuropsychological assessment included: Letter-number sequencing test (LNS), 2-back task, digit span (forwards and backwards) and the Rivermead profilet. DTI was analyzed by a tract-based spatial statics (TBSS) approach. RESULTS: Whole brain DTI analysis showed a global decrease in FA values that correlated with the 2-back d-prime index, but not with the Rivermead profile. ROI analysis revealed positive correlations between working memory performance assessed by 2-back d-prime and superior longitudinal fasciculi, corpus callosum, arcuate fasciculi and fornix. Declarative memory assessed by the Rivermead profile scores correlated with the fornix and the corpus callosum. CONCLUSIONS: Diffuse TBI is associated with a general decrease of white matter integrity. Nevertheless deficits in specific memory domains are related to different patterns of white matter damage.


Assuntos
Lesões Encefálicas/patologia , Lesões Encefálicas/psicologia , Imagem de Tensor de Difusão/métodos , Transtornos da Memória/patologia , Fibras Nervosas Mielinizadas/patologia , Vias Neurais/patologia , Adolescente , Adulto , Anisotropia , Lesões Encefálicas/complicações , Mapeamento Encefálico/métodos , Estudos Transversais , Feminino , Humanos , Masculino , Transtornos da Memória/complicações , Testes Neuropsicológicos
10.
J Womens Health (Larchmt) ; 19(6): 1073-7, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20469961

RESUMO

BACKGROUND: Chronic fatigue syndrome (CFS) is a disabling illness of unknown etiology that is characterized by fatigue associated with a reduced ability to work, lasting for more than 6 months, and accompanied by a specific set of symptoms. The diagnosis remains difficult because of the absence of laboratory tests and is, therefore, made largely on the basis of the symptoms reported by the patient. The aim of this study was to analyze differences in blood nitrate levels in CFS patients and a matched control group after a physical exercise test. METHODS: Forty-four consecutive female patients with CFS and 25 healthy women performed an exercise test using a cycle ergometer with monitoring of cardiopulmonary response. Blood samples were obtained for biochemical analyses of glucose, lactate, and nitrates at the beginning (under resting conditions) and after the maximal and supramaximal tests. RESULTS: Plasma nitrates differed between the groups, with higher values in the CFS group (F = 6.93, p = 0.003). Nitrate concentration increased in relation to workload and reached higher values in the CFS group, the maximum difference with respect to the control group being 295% (t = 4.88, p < 0.001). CONCLUSIONS: The main result of the present study is that nitric oxide (NO) metabolites (nitrates) showed a much higher increase after a maximal physical test in CFS patients than in a group of matched subjects. This combination (exercise plus NO response evaluation) may be useful in the assessment of CFS.


Assuntos
Exercício Físico/fisiologia , Síndrome de Fadiga Crônica/metabolismo , Óxido Nítrico/biossíntese , Análise de Variância , Estudos de Casos e Controles , Teste de Esforço , Síndrome de Fadiga Crônica/sangue , Feminino , Humanos , Óxido Nítrico/sangue
11.
Eur J Pharmacol ; 610(1-3): 128-33, 2009 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-19324037

RESUMO

Fructose 1,6-P2 (F1,6BP) protects rat liver against experimental hepatitis induced by galactosamine (GalN) by means of two parallel effects: prevention of inflammation, and reduction of hepatocyte sensitization to tumour necrosis factor-alpha (TNF-alpha). In a previous paper we reported the underlying mechanism involved in the prevention of inflammation. In the present study, we examined the intracellular mechanisms involved in the F1,6BP inhibition of the apoptosis induced by TNF-alpha in parenchyma cells of GalN-sensitized rat liver. We hypothesized that the increased nitric oxide (NO) production in livers of F1,6BP-treated rats mediates the antiapoptotic effect. This hypothesis was evaluated in cultured primary rat hepatocytes challenged by GalN plus tumour necrosis factor-alpha (GalN+TNF-alpha), to reproduce in vitro the injury associated with experimental hepatitis. Our results show a reduction in apoptosis concomitant with an increase in NO production and with a reduction in oxidative stress. In such conditions, guanylyl cyclase is activated and the increase in cGMP reduces the TNF-alpha-induced apoptosis in hepatocytes. These results provide new insights in the protective mechanism activated by F1,6BP and confirm its interest as a hepatoprotective agent.


Assuntos
Apoptose/efeitos dos fármacos , Frutosedifosfatos/farmacologia , Galactosamina/farmacologia , Hepatócitos/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia , Animais , Células Cultivadas , Meios de Cultura Livres de Soro , GMP Cíclico/análise , GMP Cíclico/biossíntese , Relação Dose-Resposta a Droga , Masculino , Óxido Nítrico/metabolismo , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
12.
Brain Inj ; 22(11): 882-90, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18850346

RESUMO

PRIMARY OBJECTIVE: To study cerebral response in a functional magnetic resonance imaging (fMRI) task of speech perception in a sample of patients in vegetative state (VS) and minimally conscious state (MCS) after traumatic brain injury. METHODS: Three patients in VS, four patients in MCS and 19 healthy volunteers were enrolled for the study. All subjects underwent an fMRI task of passive listening of narratives played forward and backward, alternated with periods of silence. This study analysed cerebral response to language and to complex sound processing in the healthy subjects' group and in each patient, using SPM5. RESULTS: One patient in VS and one in MCS showed cerebral responses to language and to complex sound very similar to those shown by the healthy volunteers. Two more patients, one in VS and one in MCS, showed significant responses to complex sound only. Finally, one patient in VS and one patient in MCS failed to show significant activation in response to either stimulus. CONCLUSIONS: Some patients in VS and MCS can preserve cerebral responses to language and auditory stimuli. fMRI may be useful to identify these responses, which may pass unnoticed in a bedside examination.


Assuntos
Lesões Encefálicas/psicologia , Estado de Consciência/fisiologia , Estado Vegetativo Persistente/fisiopatologia , Estimulação Acústica/métodos , Adolescente , Adulto , Percepção Auditiva/fisiologia , Conscientização , Lesões Encefálicas/complicações , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estado Vegetativo Persistente/diagnóstico , Percepção da Fala/fisiologia
13.
Neuroimage ; 43(3): 421-9, 2008 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-18771738

RESUMO

Traumatic brain injury (TBI) patients have working memory deficits and altered patterns of brain activation during this function. The evolution of the impairment has not been examined to date. This study investigated longitudinal changes in brain activation during a working memory task. Twelve patients with severe and diffuse TBI and ten healthy matched controls were fMRI scanned twice at a 6-month interval during an n-back task (0-, 2- and 3-back). All the TBI patients selected presented signs of diffuse axonal injury on CT but had no evidence of focal lesions on MRI clinical examination. Significant changes in brain activation over time were observed in patients, but not in controls. During the first examination, though both groups engaged bilateral fronto-parietal regions known to be involved in working memory, activation of the right superior frontal gyrus was low in the TBI group. However, the difference between TBI and controls had decreased significantly after 6 months. A factor analysis confirmed the greater increase in activation in the right superior frontal cortex in the TBI group than in healthy controls, leading to normalization of the brain activation pattern. In conclusion, this longitudinal study provides evidence of a progressive normalization of the working memory activation pattern after diffuse axonal injury in severe TBI, coinciding with an improvement in performance on this function.


Assuntos
Mapeamento Encefálico , Lesão Axonal Difusa/fisiopatologia , Imageamento por Ressonância Magnética , Transtornos da Memória/fisiopatologia , Adulto , Lesões Encefálicas/complicações , Lesões Encefálicas/fisiopatologia , Lesão Axonal Difusa/complicações , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Estudos Longitudinais , Masculino , Transtornos da Memória/etiologia , Memória de Curto Prazo/fisiologia , Testes Neuropsicológicos
14.
Eur J Pharmacol ; 590(1-3): 115-9, 2008 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-18602097

RESUMO

The release of reactive oxygen species has been described in hypothermic cells and tissues. Fructose 1,6-biphosphate (F1,6-BP) protects tissue stored at cold temperatures. We study the effect of F1,6-BP in vivo administration on anaesthetized rats exposed to cold stress (4 degrees C chamber for 30 min) and rewarming, to see if it alters cold-induced oxidative injury. Body temperatures show that the animals reached moderate hypothermia (26.80+/-0.62 degrees C) after 30 min of cold exposition. A decrease in mean arterial pressure was found. One group of animals was then rewarmed. Both hypothermia and rewarming increased the production of thiobarbituric acid-reactive substances, an index of lipid peroxidation, and reduced the antioxidant levels of plasmatic sulfhydryl groups, as well as decreasing the enzymatic activities of Cu,Zn-superoxide dismutase (Cu,Zn-SOD), catalase and GSH peroxidase in erythrocytes. Administration of F1,6-BP increased sulfhydryl groups and limited lipid peroxidation in plasma. It furthermore enhanced Cu,Zn-SOD and GSH peroxidase antioxidant activity in erythrocytes and preserved mean arterial pressure. Therefore, F1,6-BP has therapeutic potential based on its ability to reduce free-radical injury resulting from acute cold exposure and rewarming in vivo.


Assuntos
Frutosedifosfatos/farmacologia , Hipotermia/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Eritrócitos/enzimologia , Frutosedifosfatos/uso terapêutico , Hipotermia/tratamento farmacológico , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley , Compostos de Sulfidrila/análise
15.
Crit Care Med ; 34(3): 807-14, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16521276

RESUMO

OBJECTIVE: Fructose 1,6-bisphosphate (F1,6BP) protects organs against a wide range of challenges involving inflammation. We hypothesized that the primary action of F1,6BP is to prevent macrophage activation and cytokine release. Our aim was to determine the tissue and cellular targets for this bisphosphorylated sugar and to provide new insights into its mechanisms of action. DESIGN: Prospective, controlled laboratory study. SETTING: Animal resource facilities and research laboratory. SUBJECTS: Male Sprague-Dawley rats (200-250 g body weight). INTERVENTIONS: The protective action of F1,6BP was analyzed in galactosamine (GalN)-induced hepatitis in rats. The in vivo effects of F1,6BP were evaluated by changes in transaminase activities, blood endotoxins, and tumor necrosis factor (TNF)-alpha production in GalN-challenged rats. The targets of F1,6BP to reduce macrophage response to lipopolysaccharide (LPS) were determined by correlation between changes in TNF-alpha production and K+ fluxes through cell membrane in primary cultures of Kupffer cells. MEASUREMENTS AND MAIN RESULTS: The in vivo results indicate that F1,6BP treatment prevented GalN-induced injury in liver parenchymal cells. This protection was mainly associated with a reduction of the inflammatory response. F1,6BP prevention of GalN-induced endotoxemia correlated with preclusion of mast cell degranulation and histamine release that preceded the increased plasma endotoxins and liver production of TNF-alpha. In addition, F1,6BP treatment decreased sensitivity to LPS, which reduced the GalN-induced increase in TNF-alpha. The in vitro results show that F1,6BP inhibited Kupffer cell response and reduced TNF-alpha production by preventing LPS-induced K+ channel activation. CONCLUSIONS: The role of exogenous F1,6BP as a K+ channel modulator underlies its antihistaminic and anti-inflammatory action and increases its interest as a protective compound.


Assuntos
Frutosedifosfatos/farmacologia , Fatores Imunológicos/farmacologia , Falência Hepática Aguda/prevenção & controle , Ativação de Macrófagos/efeitos dos fármacos , Sepse/prevenção & controle , Análise de Variância , Animais , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Modelos Animais de Doenças , Galactosamina , Hepatócitos/efeitos dos fármacos , Liberação de Histamina/efeitos dos fármacos , Inflamação/prevenção & controle , Células de Kupffer/efeitos dos fármacos , Canais de Potássio/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/efeitos dos fármacos
16.
Eur J Pharmacol ; 517(3): 158-64, 2005 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-15987633

RESUMO

Inhibition of glycolysis at the phosphofructo-1-kinase step slows cell growth. For this reason, overexpression of fructose-2,6-bisphosphatase is a potential target for antineoplasic treatments. However, therapeutic objectives may be compromised by side effects of glycolysis restriction, including enhanced resistance to oxidants and tumor necrosis factor-alpha (TNF-alpha), as well as increased activity of the nuclear factor kappa B (NF-kappaB). In this study we evaluated aspirin as an adjuvant drug for glycolysis restriction by overexpression of fructose-2,6-bisphosphatase. The effect of aspirin on antioxidant defences and NF-kappaB activity were evaluated both in control cells and in fructose-2,6-bisphosphatase-overexpressing cells. Interestingly, aspirin-induced inhibition of NF-kappaB activity was greater in transfectants with restricted glycolysis than in control cells. Our results indicate that aspirin is a suitable complement to therapy based on glycolysis restriction to overcome resistance associated with increased NF-kappaB activity and oxidative stress.


Assuntos
Aspirina/farmacologia , Células Epiteliais/efeitos dos fármacos , Glicólise/fisiologia , NF-kappa B/metabolismo , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Apoptose/efeitos dos fármacos , Sítios de Ligação/genética , Western Blotting , Linhagem Celular , Relação Dose-Resposta a Droga , Células Epiteliais/metabolismo , Glutationa/metabolismo , Dissulfeto de Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Luciferases/genética , Luciferases/metabolismo , Pulmão/citologia , Fosfofrutoquinase-2/genética , Fosfofrutoquinase-2/metabolismo , Plasmídeos/genética , Ligação Proteica/efeitos dos fármacos , Ratos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Transfecção
17.
Free Radic Biol Med ; 36(12): 1555-65, 2004 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15182857

RESUMO

Transfection of genes that code for enzymes of energy metabolism provides alternative models to study the adaptive response to energy restriction induced by endogenous changes instead of by unfavorable environmental conditions. Overexpression of the glycolytic enzyme fructose-2,6-bisphosphatase reduced the content of fructose 2,6-bisphosphate, inducing energy limitation in the mink lung epithelial cell line Mv1Lu. This metabolic stress reduced the ATP available in transfected cells by 20%, which downregulated active ion transport and protein turnover. Ion homeostasis and cell function require concomitant reductions in cell membrane ion permeability and protein damage. Our results indicate that glutathione content linked these features of the adaptive response to the endogenously induced metabolic downregulation.


Assuntos
Glutationa/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Linhagem Celular , Membrana Celular/metabolismo , Regulação para Baixo , Inibidores Enzimáticos/farmacologia , Células Epiteliais/metabolismo , Radicais Livres , Glucose/metabolismo , Glicólise , Íons , Pulmão/citologia , Potenciais da Membrana , Vison , NADP/metabolismo , Ouabaína/farmacologia , Consumo de Oxigênio , Fosfofrutoquinase-2/metabolismo , Potássio/metabolismo , Canais de Potássio/metabolismo , Espécies Reativas de Oxigênio , Radioisótopos de Rubídio/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Transfecção
18.
Free Radic Biol Med ; 33(10): 1409-18, 2002 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-12419473

RESUMO

Glycolysis-depleted cells, obtained by stable transfection of fructose 2,6-bisphosphatase in mink lung epithelial cells (Mv1Lu), were less sensitive to serum withdrawal- and TNF-alpha-induced apoptosis than cells transfected with the empty vector pcDNA3 (control cells). We compared the differences in the redox status of the two transfectants and the changes produced by TNF-alpha treatment. The activities of the antioxidant enzymes catalase and glutathione peroxidase, as well as the content of reduced glutathione (GSH) and the activity of the nuclear transcription factor kappa B (NF-kappa B), were higher in pFBPase-2 clones than in control cells in all the conditions tested. TNF-alpha challenge sharpened the differences in glutathione peroxidase activity, GSH/GSSG ratios, and NF-kappa B activation between transfectants. These data indicate that glycolysis restriction at the PFK step protects cells against apoptotic stimuli by increasing the GSH content and NF-kappa B activity. This acquired feature may compromise antineoplastic treatments based on glycolytic depletion.


Assuntos
Antioxidantes/farmacologia , Células Epiteliais/metabolismo , Pulmão/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Apoptose , Linhagem Celular , Núcleo Celular/metabolismo , Separação Celular , Relação Dose-Resposta a Droga , Citometria de Fluxo , Glutamato-Cisteína Ligase/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glicólise , Luciferases/metabolismo , Vison , NF-kappa B/metabolismo , Oxirredução , Transfecção , beta-Galactosidase/metabolismo
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