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1.
Radiologia (Engl Ed) ; 66 Suppl 1: S57-S60, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38642962

RESUMEN

We present an uncommon case of a solitary fibrous tumor of the pleura with the appearance of an air-containing cystic mass. We discuss the differential diagnosis through the imaging findings, the hypothetical origins of the air component, and the possible relationship between the air component and the aggressivity of the tumor.


Asunto(s)
Quistes , Tumor Fibroso Solitario Pleural , Humanos , Tumor Fibroso Solitario Pleural/diagnóstico por imagen , Tumor Fibroso Solitario Pleural/patología , Diagnóstico Diferencial
3.
Carbohydr Polym ; 176: 117-126, 2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-28927589

RESUMEN

Nanocomposites comprising biodegradable carrageenan and glycerol (KCg) as the host polymer, with different contents of natural montmorillonite (MMT) as filler, were prepared by a solution casting process. Different techniques have been used to determine the interaction/behavior among the different components of the samples such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Transmission electron microscope (TEM) and, mainly, Dielectric relaxation spectroscopy (DRS). FTIR indicates hydrogen interaction between carrageenan matrix and silicate that is confirmed by the XRD data indicating some kind of carrageenan intercalation between the MMT layers. A rather homogenous distribution of MMT into KCg matrix were observed using transmission electron microscopy. The MMT effect on the molecular mobility at the glass transition was studied by dielectric relaxation spectroscopy. The MMT addition resulted in a slower relaxation and a wider distribution of the relaxation times. The fragility index, m, increased upon MMT incorporation, which may be attributed to a reduction in mobility chains, due to the MMT confinement of the KCg network. In addition, the apparent activation energy associated with the relaxation dynamics of the chains at Tg increased with the MMT content. The modified films developed in this paper could be used to prepare biodegradable and edible packaging films and films for biomedical applications with improved mechanical and good dielectric response.


Asunto(s)
Bentonita/química , Carragenina/química , Nanocompuestos/química , Simulación de Dinámica Molecular , Difracción de Rayos X
4.
Carbohydr Polym ; 157: 353-360, 2017 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-27987938

RESUMEN

Broadband Dielectric Relaxation Spectroscopy was performed to study the molecular dynamics of dried Bacterial Cellulose/Carboxymethyl Cellulose-Graphene Oxide (BC/CMC-GO) composites as a function of the concentration of CMC in the culture media. At low temperature the dielectric spectra are dominated by a dipolar process labelled as a ß-relaxation, whereas electrode polarization and the contribution of dc-conductivity dominate the spectra at high temperatures and low frequency. The CMC concentration affects the morphological structure of cellulose and subsequently alters its physical properties. X-ray diffractometry measurements show that increasing the concentration of CMC promotes a decrease of the Iα/Iß ratio. This structural change in BC, that involves a variation in inter- and intramolecular interactions (hydrogen-bonding interactions), affects steeply their molecular dynamics. So, an increase of CMC concentration produces a significantly decrease of the ß-relaxation strength and an increase of the dc-conductivity.


Asunto(s)
Carboximetilcelulosa de Sodio/química , Celulosa/química , Grafito/química , Simulación de Dinámica Molecular , Óxidos/química
5.
Sci Rep ; 6: 32107, 2016 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-27554448

RESUMEN

Hollow micro/nano structures form an important family of functional materials. We have used the thermal oxidation process combined with the passage of electric current during a structural phase transition to disclose a colossal mass diffusion transfer of Ti ions. This combination points to a new route for fabrication of hollow materials. A structural phase transition at high temperature prepares the stage by giving mobility to Ti ions and releasing vacancies to the system. The electric current then drives an inward delocalization of vacancies, condensing into voids, and finally turning into a big hollow. This strong physical phenomenon leading to a colossal mass transfer through ionic diffusion is suggested to be driven by a combination of phase transition and electrical current followed by chemical reaction. We show this phenomenon for Ti leading to TiO2 microtube formation, but we believe that it can be used to other metals undergoing structural phase transition at high temperatures.

6.
Cereb Cortex ; 26(7): 3205-18, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26209844

RESUMEN

Spinocerebellar ataxia 6 (SCA6), an autosomal dominant degenerative disease, is characterized by diplopia, gait ataxia, and incoordination due to severe progressive degeneration of Purkinje cells in the vestibulo- and spinocerebellum. Ocular motor deficits are common, including difficulty fixating on moving objects, nystagmus and disruption of smooth pursuit movements. In presymptomatic SCA6, there are alterations in saccades and smooth-pursuit movements. We sought to assess functional and structural changes in cerebellar connectivity associated with a visual task, hypothesizing that gradual changes would parallel disease progression. We acquired functional magnetic resonance imaging and diffusion tensor imaging data during a passive smooth-pursuit task in 14 SCA6 patients, representing a range of disease duration and severity, and performed a cross-sectional comparison of cerebellar networks compared with healthy controls. We identified a shift in activation from vermis in presymptomatic individuals to lateral cerebellum in moderate-to-severe cases. Concomitantly, effective connectivity between regions of cerebral cortex and cerebellum was at its highest in moderate cases, and disappeared in severe cases. Finally, we noted structural differences in the cerebral and cerebellar peduncles. These unique results, spanning both functional and structural domains, highlight widespread changes in SCA6 and compensatory mechanisms associated with cerebellar physiology that could be utilized in developing new therapies.


Asunto(s)
Cerebelo/diagnóstico por imagen , Cerebelo/fisiopatología , Ataxias Espinocerebelosas/diagnóstico por imagen , Ataxias Espinocerebelosas/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Mapeo Encefálico , Estudios Transversales , Imagen de Difusión Tensora , Progresión de la Enfermedad , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiopatología , Seguimiento Ocular Uniforme/fisiología , Índice de Severidad de la Enfermedad , Percepción Visual/fisiología , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/fisiopatología
7.
Sci Rep ; 5: 15128, 2015 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-26456527

RESUMEN

We report both coaxial core-shell structured microwires and ZnO microtubes with growth of nanosticks in the inner and nanowires on the outer surface as a novel hierarchical micro/nanoarchitecture. First, a core-shell structure is obtained-the core is formed by metallic Zn and the semiconducting shell is comprised by a thin oxide layer covered with a high density of nanowires. Such Zn/ZnO core-shell array showed magnetoresistance effect. It is suggested that magnetic moments in the nanostructured shell superimposes to the external magnetic field enhancing the MR effect. Second, microtubes decorated with nanowires on the external surface are obtained. In an intermediate stage, a hierarchical morphology comprised of discrete nanosticks in the inner surface of the microtube has been found. Hyperfine interaction measurements disclosed the presence of confined metallic Zn regions at the interface between linked ZnO grains forming a chain and a ZnO thicker layer. Surprisingly, the metallic clusters form highly textured thin flat regions oriented parallel to the surface of the microtube as revealed by the electrical field gradient direction. The driving force to grow the internal nanosticks has been ascribed to stress-induced migration of Zn ions due to compressive stress caused by the presence of these confined regions.

8.
Semergen ; 41(4): 199-205, 2015.
Artículo en Español | MEDLINE | ID: mdl-25016945

RESUMEN

INTRODUCTION: The economic situation has made it necessary to optimize resources by adjusting the pharmaceutical expenditure. Citicoline was (2011) the 10th drug by rank of billed amount. Its approved indications are stroke (acute and sub-acute) and head injury, but not cognitive decline associated with age, the presumed indication for most of its use. OBJECTIVES: To assess the conditions of use of citicoline in the Health Area of Tenerife, in order to detect deviations from the indications of use as stipulated in the prescribing information sheet and the pattern of prescription, with emphasis on the analysis of its use in dementia where currently it has no indication or evidence to support it. METHOD: Cross-sectional study of prescription-indication. A 680 patient sample, segmented by reference hospital (error±5%; CI: 0.95%; P=0.5) was taken from the 4036 patients with a prescription of citicoline billed during august-october 2011 (obtained from the prescription database program, Farmacanarias). RESULTS: We found that 123 patients (18.1%) had an appropriate indication. By including the prescription regimen, 28 patients (4.1%) had adequate indication and dose levels, and in only 2 patients (0.2%) an appropriate indication, dosage and duration were found. CONCLUSIONS: "The correct prescription-indication" of citicoline is inappropiate in almost all patients studied. Impact actions are needed in order to optimize prescription, improve patient safety by reducing potential interactions, and the occurrence of adverse effects, and improve efficiency by promoting savings.


Asunto(s)
Citidina Difosfato Colina/uso terapéutico , Prescripción Inadecuada/estadística & datos numéricos , Nootrópicos/uso terapéutico , Pautas de la Práctica en Medicina/estadística & datos numéricos , Anciano , Estudios Transversales , Citidina Difosfato Colina/administración & dosificación , Demencia/tratamiento farmacológico , Femenino , Humanos , Masculino , Nootrópicos/administración & dosificación , Pautas de la Práctica en Medicina/normas , Atención Primaria de Salud , España
9.
SEMERGEN, Soc. Esp. Med. Rural Gen. (Ed. impr.) ; 40(5): 247-253, jul.-ago. 2014.
Artículo en Español | IBECS | ID: ibc-125242

RESUMEN

Introducción. Aunque el tratamiento antihipertensivo puede reducir el riesgo de morbimortalidad cardiovascular, los estudios enfocados a evaluar la asociación entre fármacos antihipertensivos utilizados e incidencia de fibrilación auricular (FA) arrojan resultados dispares. Con este estudio se pretendía averiguar la posible relación entre fármaco antihipertensivo utilizado y aparición de FA. Material y métodos. Estudio de casos y controles. Casos: hipertensos con FA diagnosticada al menos un año después del inicio del tratamiento farmacológico para la hipertensión arterial. Controles: hipertensos sin FA con tratamiento antihipertensivo farmacológico durante al menos un año. Se emparejaron según sexo, edad y duración del tratamiento antihipertensivo al diagnóstico de la FA. Se estudiaron 136 casos y 132 controles. Variables: FA, fármacos antihipertensivos, control de la hipertensión arterial, tiempo de tratamiento con fármacos antihipertensivos, número de fármacos antihipertensivos. Análisis: se calcularon las OR brutas y ajustadas mediante regresión logística. Resultados. Globalmente los diuréticos estuvieron cerca de la significación estadística: OR 0,616 (IC 95% 0,365-1,040), como factor protector de aparición de FA. Los calcioantagonistas se comportaron como factor de protección de aparición de FA en el grupo de 75 años o mayores (OR 0,366; IC 95% 0,173-0,772). Conclusiones. Los calcioantagonistas en el grupo de 75 años o más se comportan como fármaco protector de la aparición de FA. Los diuréticos pudieran tener un papel protector de incidencia de FA en todos los hipertensos (AU)


Introduction. Although antihypertensive treatment can reduce the risk of cardiovascular morbimortality, studies aimed at evaluating the association between antihypertensive drug use and incidence of atrial fibrillation (AF) yield mixed results. This study aimed to determine the possible relationship between antihypertensive drug use and development of AF. Material and methods. Case control study. Cases: Hypertensive patients with AF diagnosed at least one year after the start of drug treatment for hypertension. Controls: Hypertensive patients without AF with pharmacological antihypertensive treatment for at least one year, matching by sex, age and duration of antihypertensive therapy at diagnosis of AF cases. The study included 136 cases and 132 controls. Variables: AF, antihypertensive drugs, control of hypertension, duration of treatment with antihypertensive drugs, number of antihypertensive drugs. Analysis: Crude OR were calculated, with logistic regression being used to calculate the adjusted odds ratios. Results. Overall, diuretics was close to statistical significance: OR 0.616 (95% CI 0.365 to 1.040), as a protective factor for development of AF. Calcium channel blockers behaved as a protective factor against development of AF at 75 years or older (OR 0.366; 95% CI 0.173 to 0.772), and within this age in women (OR 0.343; 95% CI 0.145-0.811). Conclusions. Calcium channel blockers in the group of 75 years or more, especially in women, worked statistically significant as a drug protecting against the appearance of AF. Diuretics may have a protective role in AF incidence in all hypertensive patients (AU)


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Fibrilación Atrial/inducido químicamente , Fibrilación Atrial/complicaciones , Fibrilación Atrial/diagnóstico , Antihipertensivos/administración & dosificación , Antihipertensivos/efectos adversos , Hipertensión/tratamiento farmacológico , Atención Primaria de Salud/métodos , Atención Primaria de Salud/tendencias , Atención Primaria de Salud , Estudios de Casos y Controles , Bloqueadores de los Canales de Calcio/uso terapéutico , Intervalos de Confianza , Modelos Logísticos , 28599
10.
Semergen ; 40(5): 247-53, 2014.
Artículo en Español | MEDLINE | ID: mdl-24485970

RESUMEN

INTRODUCTION: Although antihypertensive treatment can reduce the risk of cardiovascular morbimortality, studies aimed at evaluating the association between antihypertensive drug use and incidence of atrial fibrillation (AF) yield mixed results. This study aimed to determine the possible relationship between antihypertensive drug use and development of AF. MATERIAL AND METHODS: Case control study. CASES: Hypertensive patients with AF diagnosed at least one year after the start of drug treatment for hypertension. CONTROLS: Hypertensive patients without AF with pharmacological antihypertensive treatment for at least one year, matching by sex, age and duration of antihypertensive therapy at diagnosis of AF cases. The study included 136 cases and 132 controls. VARIABLES: AF, antihypertensive drugs, control of hypertension, duration of treatment with antihypertensive drugs, number of antihypertensive drugs. ANALYSIS: Crude OR were calculated, with logistic regression being used to calculate the adjusted odds ratios. RESULTS: Overall, diuretics was close to statistical significance: OR 0.616 (95% CI 0.365 to 1.040), as a protective factor for development of AF. Calcium channel blockers behaved as a protective factor against development of AF at 75 years or older (OR 0.366; 95% CI 0.173 to 0.772), and within this age in women (OR 0.343; 95% CI 0.145-0.811). CONCLUSIONS: Calcium channel blockers in the group of 75 years or more, especially in women, worked statistically significant as a drug protecting against the appearance of AF. Diuretics may have a protective role in AF incidence in all hypertensive patients.


Asunto(s)
Antihipertensivos/uso terapéutico , Fibrilación Atrial/prevención & control , Bloqueadores de los Canales de Calcio/uso terapéutico , Hipertensión/terapia , Factores de Edad , Anciano , Fibrilación Atrial/epidemiología , Estudios de Casos y Controles , Diuréticos/uso terapéutico , Femenino , Humanos , Incidencia , Modelos Logísticos , Masculino , Atención Primaria de Salud , Factores Sexuales
11.
Pharmacogenomics J ; 13(4): 362-8, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22688219

RESUMEN

High cholesterol levels are an established risk factor for cardiovascular disease (CVD), the world's leading cause of death. Inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A reductase (statins) are prescribed to lower serum cholesterol levels and reduce the risk of CVD. Despite the success of statins, many patients abandon treatment owing to neuromuscular adverse drug reactions (ADRs). Genome-wide association studies have identified the single-nucleotide polymorphism (SNP) rs4149056 in the SLCO1B1 gene as being associated with an increased risk for statin-induced ADRs. By studying slow-channel syndrome transgenic mouse models, we determined that statins trigger ADRs in mice expressing the mutant allele of the rs137852808 SNP in the nicotinic acetylcholine receptor (nAChR) α-subunit gene CHRNA1. Mice expressing this allele show a remarkable contamination of end-plates with caveolin-1 and develop early signs of neuromuscular degeneration upon statin treatment. This study demonstrates that genes coding for nAChR subunits may contain variants associated with statin-induced ADRs.


Asunto(s)
Aminoácidos/efectos adversos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Enfermedades Musculares/genética , Receptores Nicotínicos/genética , Alelos , Aminoácidos/administración & dosificación , Animales , Caveolina 1/genética , Caveolina 1/metabolismo , Colesterol/sangre , Regulación de la Expresión Génica , Estudio de Asociación del Genoma Completo , Humanos , Ratones , Ratones Transgénicos , Enfermedades Musculares/inducido químicamente , Polimorfismo de Nucleótido Simple
12.
Mol Psychiatry ; 18(5): 568-75, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-22710270

RESUMEN

The literature on GWAS (genome-wide association studies) data suggests that very large sample sizes (for example, 50,000 cases and 50,000 controls) may be required to detect significant associations of genomic regions for complex disorders such as Alzheimer's disease (AD). Because of the challenges of obtaining such large cohorts, we describe here a novel sequential strategy that combines pooling of DNA and bootstrapping (pbGWAS) in order to significantly increase the statistical power and exponentially reduce expenses. We applied this method to a very homogeneous sample of patients belonging to a unique and clinically well-characterized multigenerational pedigree with one of the most severe forms of early onset AD, carrying the PSEN1 p.Glu280Ala mutation (often referred to as E280A mutation), which originated as a consequence of a founder effect. In this cohort, we identified novel loci genome-wide significantly associated as modifiers of the age of onset of AD (CD44, rs187116, P=1.29 × 10⁻¹²; NPHP1, rs10173717, P=1.74 × 10⁻¹²; CADPS2, rs3757536, P=1.54 × 10⁻¹°; GREM2, rs12129547, P=1.69 × 10⁻¹³, among others) as well as other loci known to be associated with AD. Regions identified by pbGWAS were confirmed by subsequent individual genotyping. The pbGWAS methodology and the genes it targeted could provide important insights in determining the genetic causes of AD and other complex conditions.


Asunto(s)
Alanina/genética , Enfermedad de Alzheimer/genética , Predisposición Genética a la Enfermedad , Ácido Glutámico/genética , Presenilina-1/genética , Edad de Inicio , Enfermedad de Alzheimer/epidemiología , Estudios de Cohortes , Bases de Datos Factuales/estadística & datos numéricos , Femenino , Efecto Fundador , Frecuencia de los Genes , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Masculino , Mutación/genética , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo
13.
BMC Neurosci ; 13: 104, 2012 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-22920159

RESUMEN

BACKGROUND: The peri-adolescent period is a crucial developmental moment of transition from childhood to emergent adulthood. The present report analyses the differences in Power Spectrum (PS) of the Electroencephalogram (EEG) between late childhood (24 children between 8 and 13 years old) and young adulthood (24 young adults between 18 and 23 years old). RESULTS: The narrow band analysis of the Electroencephalogram was computed in the frequency range of 0-20 Hz. The analysis of mean and variance suggested that six frequency ranges presented a different rate of maturation at these ages, namely: low delta, delta-theta, low alpha, high alpha, low beta and high beta. For most of these bands the maturation seems to occur later in anterior sites than posterior sites. Correlational analysis showed a lower pattern of correlation between different frequencies in children than in young adults, suggesting a certain asynchrony in the maturation of different rhythms. The topographical analysis revealed similar topographies of the different rhythms in children and young adults. Principal Component Analysis (PCA) demonstrated the same internal structure for the Electroencephalogram of both age groups. Principal Component Analysis allowed to separate four subcomponents in the alpha range. All these subcomponents peaked at a lower frequency in children than in young adults. CONCLUSIONS: The present approaches complement and solve some of the incertitudes when the classical brain broad rhythm analysis is applied. Children have a higher absolute power than young adults for frequency ranges between 0-20 Hz, the correlation of Power Spectrum (PS) with age and the variance age comparison showed that there are six ranges of frequencies that can distinguish the level of EEG maturation in children and adults. The establishment of maturational order of different frequencies and its possible maturational interdependence would require a complete series including all the different ages.


Asunto(s)
Ondas Encefálicas/fisiología , Encéfalo/fisiología , Desarrollo Infantil/fisiología , Electroencefalografía , Análisis Multivariante , Adolescente , Factores de Edad , Mapeo Encefálico , Niño , Cognición/fisiología , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Análisis de Componente Principal , Análisis Espectral , Estadística como Asunto
14.
Neurosci Lett ; 504(3): 232-6, 2011 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-21964389

RESUMEN

Cerebellum astrocytomas are the most typical nervous system tumors in children. Several cognitive deficits have been previously described. These deficits are probably produced by cerebellar connection and gray matter damage. The present study examines attentional deficits in children operated on for cerebellum astrocytomas, using an attentional paradigm with theoretical and clinical bases: the Attentional Network Test (ANT). This test was designed considering the attentional network theory proposed by Posner, and its usefulness has been demonstrated in clinical settings. Children operated on for cerebellar astrocytoma showed a mild attentional deficit in the orientation network.


Asunto(s)
Astrocitoma/psicología , Atención/fisiología , Neoplasias Cerebelosas/psicología , Cerebelo/fisiopatología , Red Nerviosa/fisiopatología , Orientación/fisiología , Conducta Espacial/fisiología , Astrocitoma/complicaciones , Astrocitoma/fisiopatología , Astrocitoma/cirugía , Mapeo Encefálico , Neoplasias Cerebelosas/complicaciones , Neoplasias Cerebelosas/fisiopatología , Neoplasias Cerebelosas/cirugía , Niño , Señales (Psicología) , Femenino , Fijación Ocular/fisiología , Lóbulo Frontal/fisiopatología , Humanos , Discapacidades para el Aprendizaje/etiología , Discapacidades para el Aprendizaje/fisiopatología , Masculino , Pruebas Neuropsicológicas , Lóbulo Parietal/fisiopatología , Enmascaramiento Perceptual/fisiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/fisiopatología , Desempeño Psicomotor
15.
Neurology ; 77(11): 1055-60, 2011 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-21880993

RESUMEN

OBJECTIVE: To provide clinical data on a cohort of 6 patients with massive expansion (>200 CAG repeats) of spinocerebellar ataxia type 2 (SCA2) and investigate possible pathways of pathogenesis using bioinformatics analysis of ATXN2 networks. METHODS: We present data on 6 patients with massive expansion of SCA2 who presented in infancy with variable combinations of hypotonia, global developmental delay, infantile spasms, and retinitis pigmentosa. ATXN2 is known to interact with a network of synaptic proteins. To investigate pathways of pathogenesis, we performed bioinformatics analysis on ATXN2 combined with known genes associated with infantile spasms, retinitis pigmentosa, and synaptic function. RESULTS: All patients had a progressive encephalopathy with autonomic dysfunction, 4 had retinitis pigmentosa, and 3 had infantile spasms. The bioinformatics analysis led to several interesting findings. First, an interaction between ATXN2 and SYNJ1 may account for the development of retinitis pigmentosa. Second, dysfunction of postsynaptic vesicle endocytosis may be important in children with this progressive encephalopathy. Infantile spasms may be associated with interactions between ATXN2 and the postsynaptic structural proteins MAGI2 and SPTAN1. CONCLUSIONS: Severe phenotype in children with massive expansion of SCA2 may be due to a functional deficit in protein networks in the postsynapse, specifically involving vesicle endocytosis.


Asunto(s)
Enfermedades del Sistema Nervioso Autónomo/genética , Retinitis Pigmentosa/genética , Espasmos Infantiles/genética , Expansión de Repetición de Trinucleótido/genética , Ataxinas , Enfermedades del Sistema Nervioso Autónomo/diagnóstico , Enfermedades del Sistema Nervioso Autónomo/metabolismo , Preescolar , Resultado Fatal , Femenino , Humanos , Lactante , Masculino , Proteínas del Tejido Nervioso/deficiencia , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/fisiología , Fenotipo , Densidad Postsináptica/genética , Retinitis Pigmentosa/diagnóstico , Retinitis Pigmentosa/metabolismo , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Espasmos Infantiles/diagnóstico , Espasmos Infantiles/metabolismo
16.
Clin Otolaryngol ; 36(5): 482-8, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21838807

RESUMEN

OBJECTIVES: Suboptimal standards in tracheostomy care have been highlighted as a growing concern in view of the increasing demands for intensive care services. Our objective is to assess the impact of our model for tracheostomy care on patients with short-term tracheostomies (<4 months in situ) following their discharge from the intensive care unit. The model has three components: The St Mary's tracheostomy care bundle checklist, a dedicated tracheostomy multidisciplinary team and an educational programme. DESIGN: A 38-month prospective cohort study. SETTING: A London Teaching Hospital. PARTICIPANTS: A total of 102 patients with tracheostomy within the 19-month pre-intervention cohort and 95 patients in the 19-month post-intervention cohort. MAIN OUTCOME MEASURES: The number of clinical incidents, mean time taken for decannulation, mean total tracheostomy time and total number of days spent in the intensive care unit were assessed before and after the intervention. RESULTS: Time to decannulation following intensive care unit discharge decreased from 21 to 11 days, as did the mean total tracheostomy time, from 34 to 25 days (both statistically significant with a P < 0.0001 Mann-Whitney U-test). The number of critical incidents, which included all patients prior to exclusion, substantially declined following the introduction of intervention from 58 to 7 in the second year after intervention. CONCLUSIONS: A multidisciplinary care model significantly expedited the decannulation process and reduced the overall time that a tracheostomy was in situ. The intervention was associated with a reduction in clinical incidents and shorter intensive care unit admissions, which can be associated with significant monetary savings.


Asunto(s)
Grupo de Atención al Paciente/normas , Atención al Paciente/normas , Traqueostomía , APACHE , Femenino , Hospitales de Enseñanza , Humanos , Unidades de Cuidados Intensivos , Londres , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estadísticas no Paramétricas
17.
Int J Neurosci ; 118(1): 27-38, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18041604

RESUMEN

Event-related potentials (ERPs) and power spectral density (PSD) were registered during an auditory-oddball paradigm in 11 MS patients. These patients showed a decrease in the amplitude of P2 and N2 components and a delayed P3 latency compared to control subjects suggesting that the attentional orienting mechanism in the auditory modality is affected in MS. The PSD analysis showed that MS patients exhibited an increased power in beta and gamma bands. The combined analysis of frequency and time domain suggested diverse phenomena that occurred in the MS patient group related with the EEG background or the motivational status.


Asunto(s)
Discriminación en Psicología , Potenciales Evocados Auditivos , Esclerosis Múltiple Recurrente-Remitente/fisiopatología , Tiempo de Reacción , Localización de Sonidos , Estimulación Acústica , Adulto , Atención , Electroencefalografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Orientación , Espectrografía del Sonido
18.
J Biosci ; 33(5): 743-753, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19179762

RESUMEN

The relationship between stimulus intensity and the probability of detecting the presence of the stimulus is described by the psychometrical function.The probabilistic nature of this relationship is based on the stochastic behaviour of sensory neural channels and sensory networks involved in perceptual processing (Kiang 1968). This study tries to establish a continuum of variability across different levels of integration in the central nervous system. Once the opening and closing times of ionic channels was simulated, a threshold to the collective behaviour of voltage-gated ionic channels was imposed in order to generate the spike train of a single neuron. Afterwards,the trains of spikes of different neurons were added up,simulating the activity of a sensory nerve. By adding the activity due to the stimulus to the spontaneous neural behaviour,the psychometric function was simulated using a thresholding approach.The results can replicate the stochastic resonance phenomenon, but also open up the possibility that attentional phenomena can be mediated not only by increasing neural activity (bursting or oscillatory),but also by increasing noise at the neural level.


Asunto(s)
Simulación por Computador , Activación del Canal Iónico/fisiología , Modelos Biológicos , Red Nerviosa/fisiología , Neuronas/fisiología , Psicometría , Electrofisiología , Humanos
20.
Brain Res ; 1107(1): 151-60, 2006 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-16875680

RESUMEN

To test the hypothesis that there is a functional modulation of conventional EEG bands associated with preparatory attention, putative changes in the spontaneous brain rhythms and their associated cerebral sources were addressed. The goals of the present report were, first, to find the brain areas with maximal rhythmic activity before warning and imperative stimuli in a classic contingent negative variation (CNV) paradigm, and, second, to study the modulation of the EEG rhythms of these areas during the preparatory attention interval which precedes the S2 (imperative) stimulus. Trial by trial LORETA analysis found similar brain rhythm generators during both pre-S1 and pre-S2 intervals. Each theta, alpha and beta traditional EEG rhythm originates in several anatomically distinct brain structures. Preparatory attention is associated with a decrease in power in alpha (right and left occipital and temporal areas) and low-beta (left frontal, bilateral occipital and middle frontal areas) EEG bands. In these structures power changes associated with preparatory attention modulated either a dominant or a non-dominant oscillatory band, suggesting that non-dominant rhythms of a cerebral area have some functional relevance. Our results imply distributed regional sources for brain rhythms and support the view that during preparatory attention there is a modulation of the brain sources generating alpha and beta brain rhythms. Moreover, the proposed combined approach makes it possible to explore the definition of a given brain area not only anatomically, but also by the frequency content and the functional reactivity of the electrical rhythms that it generates.


Asunto(s)
Atención/fisiología , Mapeo Encefálico , Encéfalo/fisiología , Variación Contingente Negativa/fisiología , Adolescente , Adulto , Encéfalo/anatomía & histología , Electroencefalografía/métodos , Femenino , Humanos , Masculino , Estimulación Luminosa/métodos , Tiempo de Reacción/fisiología , Análisis Espectral/métodos
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