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1.
Radiologia (Engl Ed) ; 65(3): 269-284, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37268369

RESUMO

Magnetic resonance has become a first-line imaging modality in various clinical scenarios. The number of patients with different cardiovascular devices, including cardiac implantable electronic devices, has increased exponentially. Although there have been reports of risks associated with exposure to magnetic resonance in these patients, the clinical evidence now supports the safety of performing these studies under specific conditions and following recommendations to minimize possible risks. This document was written by the Working Group on Cardiac Magnetic Resonance Imaging and Cardiac Computed Tomography of the Spanish Society of Cardiology (SEC-GT CRMTC), the Heart Rhythm Association of the Spanish Society of Cardiology (SEC-Heart Rhythm Association), the Spanish Society of Medical Radiology (SERAM), and the Spanish Society of Cardiothoracic Imaging (SEICAT). The document reviews the clinical evidence available in this field and establishes a series of recommendations so that patients with cardiovascular devices can safely access this diagnostic tool.


Assuntos
Cardiologia , Cardiopatias , Humanos , Consenso , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética
2.
Radiología (Madr., Ed. impr.) ; 65(3): 269-284, May-Jun. 2023. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-221008

RESUMO

La resonancia magnética se ha convertido en técnica de imagen de primera línea en muchas situaciones clínicas. El número de pacientes portadores de dispositivos cardiovasculares, como los dispositivos cardiovasculares electrónicos implantables, ha crecido de modo exponencial. Aunque se han descrito complicaciones y efectos adversos cuando estos pacientes se someten a exploraciones de resonancia magnética, la evidencia clínica actual respalda la seguridad de realizar estos estudios cuando se cumplen unas normas y recomendaciones dirigidas a minimizar los posibles riesgos. El Grupo de Trabajo de Cardiorresonancia Magnética y Cardiotomografía Computarizadas de la Sociedad Española de Cardiología (SEC-GT CRMTC), la Asociación del Ritmo Cardiaco de la Sociedad Española de Cardiología (SEC-Asociación del Ritmo Cardiaco de la Sociedad Española de Cardiología), la Sociedad Española de Radiología Médica (SERAM) y la Sociedad Española de Imagen Cardiotorácica (SEICAT) han elaborado el presente documento, que revisa la evidencia disponible en este campo y establece las recomendaciones necesarias para que los pacientes portadores de dispositivos cardiovasculares electrónicos implantables y otros dispositivos puedan acceder con seguridad a este instrumento diagnóstico.(AU)


Magnetic resonance has become a first-line imaging modality in various clinical scenarios. The number of patients with different cardiovascular devices, including cardiac implantable electronic devices, has increased exponentially. Although there have been reports of risks associated with exposure to magnetic resonance in these patients, the clinical evidence now supports the safety of performing these studies under specific conditions and following recommendations to minimize possible risks. This document was written by the Working Group on Cardiac Magnetic Resonance Imaging and Cardiac Computed Tomography of the Spanish Society of Cardiology (SEC-GT CRMTC), the Heart Rhythm Association of the Spanish Society of Cardiology (SEC-Heart Rhythm Association), the Spanish Society of Medical Radiology (SERAM), and the Spanish Society of Cardiothoracic Imaging (SEICAT). The document reviews the clinical evidence available in this field and establishes a series of recommendations so that patients with cardiovascular devices can safely access this diagnostic tool.(AU)


Assuntos
Humanos , Masculino , Feminino , Espectroscopia de Ressonância Magnética , Técnicas de Diagnóstico Cardiovascular , Equipamentos e Provisões , Técnicas e Procedimentos Diagnósticos , Segurança do Paciente , Marca-Passo Artificial , Desfibriladores Implantáveis , Radiologia , Consenso
3.
J Cardiovasc Magn Reson ; 22(1): 62, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32878630

RESUMO

BACKGROUND: Intensive endurance exercise may induce a broad spectrum of right ventricular (RV) adaptation/remodelling patterns. Late gadolinium enhancement (LGE) has also been described in cardiovascular magnetic resonance (CMR) of some endurance athletes and its clinical meaning remains controversial. Our aim was to characterize the features of contrast CMR and the observed patterns of the LGE distribution in a cohort of highly trained endurance athletes. METHODS: Ninety-three highly trained endurance athletes (> 12 h training/week at least during the last 5 years; 36 ± 6 years old; 53% male) and 72 age and gender-matched controls underwent a resting contrast CMR. In a subgroup of 28 athletes, T1 mapping was also performed. RESULTS: High endurance training load was associated with larger bi-ventricular and bi-atrial sizes and a slight reduction of biventricular ejection fraction, as compared to controls in both genders (p < 0.05). Focal LGE was significantly more prevalent in athletes than in healthy subjects (37.6% vs 2.8%; p < 0.001), with a typical pattern in the RV insertion points. In T1 mapping, those athletes who had focal LGE had higher extracellular volume (ECV) at the remote myocardium than those without (27 ± 2.2% vs 25.2 ± 2.1%; p < 0.05). CONCLUSIONS: Highly trained endurance athletes showed a ten-fold increase in the prevalence of focal LGE as compared to control subjects, always confined to the hinge points. Additionally, those athletes with focal LGE demonstrated globally higher myocardial ECV values. This matrix remodelling and potential presence of myocardial fibrosis may be another feature of the athlete's heart, of which the clinical and prognostic significance remains to be determined.


Assuntos
Atletas , Cardiomegalia Induzida por Exercícios , Meios de Contraste/administração & dosagem , Coração/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética , Compostos Organometálicos/administração & dosagem , Resistência Física , Função Ventricular Direita , Remodelação Ventricular , Adaptação Fisiológica , Adulto , Estudos de Casos e Controles , Feminino , Fibrose , Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Valor Preditivo dos Testes , Volume Sistólico , Função Ventricular Esquerda , Adulto Jovem
4.
Eur J Appl Physiol ; 120(6): 1227-1235, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32130484

RESUMO

AIMS: Endurance athletes develop cardiac remodeling to cope with increased cardiac output during exercise. This remodeling is both anatomical and functional and shows large interindividual variability. In this study, we quantify local geometric ventricular remodeling related to long-standing endurance training and assess its relationship with cardiovascular performance during exercise. METHODS: We extracted 3D models of the biventricular shape from end-diastolic cine magnetic resonance images acquired from a cohort of 89 triathlon athletes and 77 healthy sedentary subjects. Additionally, the athletes underwent cardio-pulmonary exercise testing, together with an echocardiographic study at baseline and few minutes after maximal exercise. We used statistical shape analysis to identify regional bi-ventricular shape differences between athletes and non-athletes. RESULTS: The ventricular shape was significantly different between athletes and controls (p < 1e-6). The observed regional remodeling in the right heart was mainly a shift of the right ventricle (RV) volume distribution towards the right ventricular infundibulum, increasing the overall right ventricular volume. In the left heart, there was an increment of left ventricular mass and a dilation of the left ventricle. Within athletes, the amount of such remodeling was independently associated to higher peak oxygen pulse (p < 0.001) and weakly with greater post-exercise RV free wall longitudinal strain (p = 0.03). CONCLUSIONS: We were able to identify specific bi-ventricular regional remodeling induced by long-lasting endurance training. The amount of remodeling was associated with better cardiopulmonary performance during an exercise test.


Assuntos
Tolerância ao Exercício/fisiologia , Exercício Físico/fisiologia , Coração/diagnóstico por imagem , Resistência Física/fisiologia , Remodelação Ventricular/fisiologia , Adulto , Atletas , Ecocardiografia , Treino Aeróbico , Teste de Esforço , Feminino , Frequência Cardíaca/fisiologia , Humanos , Imagem Cinética por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Adulto Jovem
5.
J Phys Condens Matter ; 29(8): 085405, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28095369

RESUMO

The transition taking place between two metastable phases in 2-O-adamantane, namely the [Formula: see text] cubic, rotator phase and the lower temperature P21/c, Z = 4 substitutionally disordered crystal is studied by means of muon spin rotation and relaxation techniques. Measurements carried out under zero, weak transverse and longitudinal fields reveal a temperature dependence of the relaxation parameters strikingly similar to those exhibited by structural glass[Formula: see text]liquid transitions (Bermejo et al 2004 Phys. Rev. B 70 214202; Cabrillo et al 2003 Phys. Rev. B 67 184201). The observed behaviour manifests itself as a square root singularity in the relaxation rates pointing towards some critical temperature which for amorphous systems is located some tens of degrees above that shown as the characteristic transition temperature if studied by thermodynamic means. The implications of such findings in the context of current theoretical approaches concerning the canonical liquid-glass transition are discussed.

6.
Med. infant ; 23(2): 86-89, junio 2016. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-882145

RESUMO

La heminefrectomía puede constituir el tratamiento definitivo en el 85% de los pacientes con diagnóstico de doble sistema con uno de los mismos no funcionante. Actualmente el abordaje laparoscópico es de elección tanto por sus resultados estéticos como evolución postoperatoria. Materiales y métodos: se efectuó una revisión y análisis retrospectivo de todos los pacientes operados de heminefrectomía desde el año 2000 a 2014. Resultados: 44 pacientes fueron operados de forma convencional durante el período 2000-2010 y 30 de forma laparoscópica transperitoneal durante el período 2010-2014. La media de duración del procedimiento fue menor para el grupo convencional (89,6 vs 128 min, p = 0,000) mientras que la media de estadía hospitalaria fue menor para el grupo laparoscópico (4,2 vs 5,1, p = 0,19). La tasa de reoperación fue mayor en el grupo convencional (20,4% vs 6,7%, p = 0,18) y la principal causa fue por la presencia un muñón ureteral sintomático. En los controles por centellograma DMSA (en 19 pacientes del segundo grupo) no se objetivó la pérdida de función de la unidad remanente en ningún individuo. Conclusiones: La heminefrectomía es un procedimiento seguro con baja tasa de complicaciones cuya tendencia actual es realizar la cirugía de forma laparoscópica obteniendo resultados similares y menor tasa de complicaciones que en la forma convencional (AU)


Heminephrectomy may be the definitive treatment in 85% of patients diagnosed with a duplex kidney system of which one is not working. Currently, a laparoscopic approach is the treatment of choice because of both esthetic results and postoperative outcome. Material and methods: A retrospective analysis of all patients who underwent heminephrectomy between 2000 and 2014 was conducted. Results: 44 patients underwent conventional surgery in the period 2000-2010 and 30 underwent transperitoneal laparoscopy in the period 2010-2014. Mean duration of the procedure was less in the conventional group (89.6 vs 128 min, p = 0.000), while the mean hospital stay was less in the laparoscopic group (4.2 vs 5.1, p = 0.19). Reoperation rate was higher in the conventional group (20.4% vs 6.7%, p = 0.18) and the main cause was presence of a symptomatic ureteral stump. On DMSA whole body scan controls (in 19 patients in the second group) no loss of function of the remaining unit was observed in any of the patients. Conclusions: Heminephrectomy is a safe procedure with a low complication rate and a current trend to be performed using laparoscopy with similar results and a lower complication rate than in conventional surgery (AU)


Assuntos
Humanos , Lactente , Pré-Escolar , Criança , Adolescente , Rim/anormalidades , Rim/cirurgia , Laparoscopia/métodos , Nefrectomia/métodos , Resultado do Tratamento , Doenças Urológicas/congênito , Estudos Retrospectivos
7.
Med. infant ; 23(2): 96-100, junio 2016. tab, ilus
Artigo em Espanhol | LILACS | ID: biblio-882209

RESUMO

Reportar nuestra experiencia inicial de nefrolitotomía percutánea (NLPC) con láser Holmium para el tratamiento de litiasis renal en la población pediátrica. Material y métodos: Estudio retrospectivo descriptivo de pacientes menores de 16 años con litiasis renal que fueron tratados con nefrolitotomía percutánea en el servicio de Urología del Hospital Garrahan en el período comprendido entre agosto de 2013 y marzo de 2015. Resultados: 19 procedimientos en 16 pacientes con un número de 17 unidades renales (UR) con una edad media de 7 años y un rango de 2 a 15 (Tabla 2). Los tipos de litiasis tratadas fueron: litiasis coraliforme en 6 pacientes (37,5%), coraliforme incompleto en 3 pacientes (18,7%), litiasis piélicas mayores de 2 cm en 4 pacientes (25%), litiasis piélicas menores de 2 cm en 2 pacientes (12,5%) y múltiples mayores de 2 cm en 1 paciente (6,25%). Se realizó acceso único en 15 pacientes, en sólo uno se configuró un segundo acceso y se reingresó o se realizó cirugía en dos tiempos en 3 pacientes (todos con litiasis coraliforme completa). La tasa de litiasis residual total fue del 21,1 %, todas ellas en litiasis coraliformes completas. Las complicaciones se observaron en 3 casos (18,7%) y fueron clasificadas como tipo III B en dos pacientes y del tipo I en uno. En los dos primeros se requirió conversión a vía abierta y en el último paciente solo se dejó colocada nefrostomía por 7 días. La internación promedio fue de 2,8 días con un rango de 1 a 15 días. El seguimiento medio fue de 7 meses con un rango de 4 a 13 meses. Conclusiones: La nefrolitotomía percutánea en pediatría es un método con baja morbilidad, que requiere una curva de aprendizaje prolongada y es determinante contar con todo el material necesario para "liberar" al riñón de litiasis urinaria (AU)


The aim of the study was to report our initial experience with percutaneous nephrolithotomy (PCNL) with holmium laser for the treatment of kidney stones in children. Material and methods: A descriptive retrospective analysis was conducted in patients younger than 16 years with kidney stones treated with PCNL at the department of urology of Garrahan Hospital between August 2013 and March 2015. Results: 19 procedures were performed in 16 patients with a number of 17 renal units (RU) and a mean age of 7 years, ranging from 2 to 15 years (Table 2). Types of kidney stones were: Staghorn kidney stones 6 patients (37.5%), partial staghorn kidney stones in 3 patients (18.7%), renal pelvis kidney stones larger than 2 cm in 4 patients (25%), renal pelvis kidney stones smaller than 2 cm in 2 patients (12.5%), and multiple kidney stones larger than 2 cm in 1 patient (6.25%). A single tract was performed in 15 patients, a second tract in only one, and re-entry or a two-step surgery was performed in 3 patients (all with complete staghorn kidney stones). The rate of residual stones was 21.1 %, all of them were complete staghorn stones. Complications occurred in 3 cases (18.7%) and were classified as type III B in two patients and type I in one. In the first two patients conversion to open surgery was necessary and in the remaining patient the nephrostomy was left in place for 7 days. Mean hospital stay was 2.8 days with a range of 1 to 15 days. Mean follow-up time was 7 months with a range of 4 to 13 months. Conclusions: In children PCNL is a procedure with low morbidity requiring a long learning curve. Availability of all the necessary materials is essential to be able to "release" the kidney from the stones (AU)


Assuntos
Humanos , Pré-Escolar , Criança , Adolescente , Cálculos Renais , Lasers de Estado Sólido/uso terapêutico , Nefrolitíase/diagnóstico por imagem , Nefrolitíase/cirurgia , Nefrolitotomia Percutânea/métodos , Resultado do Tratamento , Estudos Retrospectivos
8.
Med. infant ; 23(2): 101-107, junio 2016. tab
Artigo em Espanhol | LILACS | ID: biblio-882251

RESUMO

Introducción: Onabotulinumtoxina es una alternativa terapéutica de segunda línea en pacientes sin respuesta a los anticolinérgicos. Objetivo: Evaluar los efectos de repetidas inyecciones de onabotulinumtoxina en vejigas neurogénicas refractarias al tratamiento clásico. Pacientes y métodos: Se evaluaron 82 pacientes menores de 18 años con vejiga neurogénica, en su mayoría por disrafia espinal. Todos fueron refractarios a oxibutinina oral. Si luego del tercer mes de la primer inyección en el detrusor se constataba mejoría clínica y/o urodinámica; se reinyectaban entre los 9 y 12 meses, nuevamente. De lo contrario, se indicaba cistoplastia de aumento. En algunos casos se utilizaron otros procedimientos endoscópicos - quirúrgicos accesorios. Resultados: Se reinyectaron con Onabotulinumtoxina, dos, tres, cuatro y cinco veces: 20 casos, 7, 4 y un caso, respectivamente. En el 51% promedio se logró continencia urinaria total (score cero-seco). En la primera y segunda inyección hubo incremento significativo en la media de capacidad cistométrica: de 254 a 331 ml (p: 0.007) y de 257 a 367 ml (p: 0.014); respectivamente. En algunos casos, luego de la primer inyección mejoró significativamente la compliance: de 6,9 a 11,4 ml/cmH2O (p: 0.05). La media de presión del detrusor al final del llenado disminuyó en promedio de 37 a 34,4 cmH2O. La sobreactividad del detrusor (n:22) se atenuó en el 54,4% luego de la primer inyección. No se registraron efectos adversos mayores con las reinyecciones. En 15 pacientes refractarios a OnabotulinumtoxinA se realizó ampliación vesical. Conclusión: Luego del tratamiento con onabotulinumtoxina, la continencia urinaria alcanzada fue del 50% promedio. La capacidad cistometrica se incrementó significativamente con las dos primeras inyecciones; aunque no se acompañó paralelamente de un importante descenso de presiones endovesicales. El uso de onabotulinumtoxina ha logrado suprimir o retrasar la clásica indicación de cistoplastia de aumento en niños refractarios a los anticolinérgicos (AU)


Introduction: OnabotulinumtoxinA is a second-line alternative therapy for patients who do not respond to anticholinergics. Aim: To evaluate the impact of repeated injections of OnabotulinumtoxinA in neurogenic bladders refractory to conventional treatment. Patients and methods: 82 patients younger than 18 years with a neurogenic bladder, in the majority due to spinal dysraphism, were evaluated. All were refractory to oral oxybutynin. If in the third month after the first injection in the detrusor clinical and/or urodynamic improvement was observed, between 9 and 12 months later a second injection was given. If not, augmentation cystoplasty was indicated. In some cases other endoscopic/surgical procedures were used. Results: Twenty, seven, four, and one case were reinjected with OnabotulinumtoxinA, two, three, four, and five times, respectively. In a mean of 51% of the patients total urinary continence was achieved (score zero - completely dry). On the first and second injection a significant increase of the maximum cystometric capacity was observed: from 254 to 331 ml (p: 0.007) and from 257 to 367 ml (p: 0.014), respectively. In some cases, after the first injection compliance improved significantly: from 6.9 to 11.4 ml/cmH2O (p: 0.05). Mean end filling detrusor pressure diminished from 37 to 34.4 cmH2O. Detrusor overactivity (n: 22) attenuated in 54.4% after the first injection. No major adverse effects were recorded after the reinjections. In 15 patients that were refractory to OnabotulinumtoxinA augmentation cystoplasty was performed. Conclusion: After OnabotulinumtoxinA treatment, 50% urinary continence was achieved. Cystometric capacity increased significantly after the first two injections; however, it was not associated with an important decrease of intravesical pressure. The use of OnabotulinumtoxinA may avoid or delay the classical indication of augmentation cystoplasty in anticholinergicrefractory children (AU)


Assuntos
Humanos , Lactente , Pré-Escolar , Criança , Adolescente , Toxinas Botulínicas Tipo A/uso terapêutico , Bexiga Urinaria Neurogênica/diagnóstico , Bexiga Urinaria Neurogênica/tratamento farmacológico , Incontinência Urinária/diagnóstico , Incontinência Urinária/tratamento farmacológico , Administração Intravesical , Estudos Prospectivos , Retratamento
9.
Med. infant ; 23(2): 117-120, junio 2016. tab, ilus
Artigo em Espanhol | LILACS | ID: biblio-882272

RESUMO

Antecedentes y Objetivos: La práctica de la colocación de stent en la anastomosis ureteral en trasplante es controvertido. Los beneficios del stent incluyen: descompresión continua del uréter con menor tensión anastomótica y alineamiento ureteral que protege de la obstrucción. Las desventajas: infección urinaria, obstrucción a largo plazo de la unión ureterovesical, hematuria por erosión mucosa y el retiro del mismo bajo sedación por vía endoscópica. Es nuestro objetivo investigar la incidencia de complicaciones con la utilización de stent ureteral vs. tutor ureteral en el trasplante renal pediátrico. Material y Métodos: Valoración retrospectiva de pacientes trasplantados renales en nuestra institución con técnica de Lich-Gregoir en el implante ureteral en el período febrero 2008 a marzo 2014. Dos grupos de pacientes para investigar complicaciones: aquellos con tutor ureteral por período de 5 dias vs. los pacientes en los que se utilizó catéter doble jota (stent) por período de 30 días. Se identificaron los pacientes con uropatía y nefropatía como causa de insuficiencia renal crónica terminal (IRCT) y se asociaron a las complicaciones que fueron divididas en no infecciosas (urológicas) y en infecciosas (infección urinaria). Resultados: Se evaluaron 183 pacientes. En el grupo con tutor ureteral (n=68) se presentaron complicaciones urológicas en 8 pacientes (11.76%), 2 urópatas y 6 nefrópatas y las complicaciones infecciosas se observaron en 15 pacientes (22.06%). En el grupo stent (n=115) se presentaron complicaciones urológicas en 3 casos (2,61%), 2 urópatas y un nefrópata y las complicaciones infecciosas se observaron en 43 pacientes (37.39%). Conclusiones: La asociación de la técnica de Lich Gregoir con stent mejora la morbilidad evitando complicaciones no infecciosas, pero aumenta la incidencia de complicaciones infecciosas independiente del origen de la causa de la IRCT (AU)


Background and aims: Stent placement in ureteral anastomosis is controversial. Benefits of the stent include: continuous decompression of the ureter with less anastomotic tension and ureteral alignment with better protection from ureteral narrowing. Disadvantages: urinary infection, long-term stricture of the vesicoureteral junction, hematuria due to mucosal erosion and its endoscopic removal under sedation. Our aim was to assess the incidence of complications of the use of a ureteral stent vs. ureteral splint in pediatric kidney transplantation. Material and methods: Retrospective assessment of kidney transplant patients in whom the Lich-Gregoir technique was used for ureteral implantation between February 2008 and March 2014. Two groups of patients were selected to assess complications: Patients with a ureteral splint for 5 days vs. patients in whom a double J catheter (stent) was used for 30 days. Patients with uropathy and nephropathy due to end-stage chronic renal failure (ESRD) were identified and associated complications were divided into non-infectious (urological) and infectious (urinary infection) complications. Results: 183 patients were evaluated. In the ureteral splint group (n=68), urological complications were observed in 8 patients (11.76%), 2 uropathic and 6 nephropathic, and infectious complications were observed in 15 patients (22.06%). In the stent group (n=115), urological complications were observed in 3 cases (2.61%), 2 uropathic and 1 nephropathic, and infectious complications were seen in 43 patients (37.39%). Conclusions: The association of the Lich Gregoir technique with stent placement improves morbidity avoiding non-infectious complications, but increases the incidence of infectious complications regardless of the cause of ESRD (AU)


Assuntos
Humanos , Criança , Adolescente , Anastomose Cirúrgica , Transplante de Rim , Complicações Pós-Operatórias , Reimplante , Stents/efeitos adversos , Ureter/cirurgia , Cateteres Urinários , Estudos Retrospectivos
10.
Brain Imaging Behav ; 10(3): 660-8, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26239997

RESUMO

The objective of this study was to investigate the relationship between cardiorespiratory (CR) fitness and the brain's white matter tract integrity using diffusion tensor imaging (DTI) in the Alzheimer's disease (AD) population. We recruited older adults in the early stages of AD (n = 37; CDR = 0.5 and 1) and collected cross-sectional fitness and diffusion imaging data. We examined the association between CR fitness (peak oxygen consumption [VO2peak]) and fractional anisotropy (FA) in AD-related white matter tracts using two processing methodologies: a tract-of-interest approach and tract-based spatial statistic (TBSS). Subsequent diffusivity metrics (radial diffusivity [RD], mean diffusivity [MD], and axial diffusivity [A × D]) were also correlated with VO2peak. The tract-of-interest approach showed that higher VO2peak was associated with preserved white matter integrity as measured by increased FA in the right inferior fronto-occipital fasciculus (p = 0.035, r = 0.36). We did not find a significant correlation using TBSS, though there was a trend for a positive association between white matter integrity and higher VO2peak measures (p < 0.01 uncorrected). Our findings indicate that higher CR fitness levels in early AD participants may be related to preserved white matter integrity. However to draw stronger conclusions, further study on the relationship between fitness and white matter deterioration in AD is necessary.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/fisiopatologia , Aptidão Cardiorrespiratória , Substância Branca/diagnóstico por imagem , Idoso , Estudos Transversais , Imagem de Tensor de Difusão , Teste de Esforço , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Comportamento Sedentário
13.
J Colloid Interface Sci ; 436: 132-7, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25268816

RESUMO

In this work we report on the permittivity of suspensions of elongated goethite particles in silicone oils of different viscosities. In spite of the low conductivity of the systems, the electrode polarization is significant. To correct this phenomenon, the procedure chosen is the one called logarithmic derivative of the real part of the permittivity, and it proves to efficiently reduce the effect of electrodes to the extent that the spectra of pure liquids are flat in the accessible frequency range (20 Hz-1 MHz). In our suspensions, we observe the presence of a dielectric relaxation for frequencies in the range 4-40 kHz. In principle, such relaxations might be ascribed to the Maxwell-Wagner (MW) polarization. However, it is found that both the characteristic frequency and the relaxation amplitude of the suspensions increase with volume fraction, something unexpected for an MW relaxation. Such discrepancy can be explained by considering the Frenkel-Trukhan model, which reproduces the Maxwell-Wagner results in conditions of thin electrical double layers (which it is not our case). An excellent agreement is found between our data and the model predictions, using only the particle surface charge as a parameter.

14.
Neuroscience ; 270: 139-47, 2014 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-24735819

RESUMO

The goal of this study was to compare insulin resistance in aging and aging-related neurodegenerative diseases, and to determine the relationship between insulin resistance and gray matter volume (GMV) in each cohort using an unbiased, voxel-based approach. Insulin resistance was estimated in apparently healthy elderly control (HC, n=21) and neurodegenerative disease (Alzheimer's disease (AD), n=20; Parkinson's disease (PD), n=22) groups using Homeostasis Model Assessment of Insulin Resistance 2 (HOMA2) and intravenous glucose tolerance test (IVGTT). HOMA2 and GMV were assessed within groups through General Linear Model multiple regression. We found that HOMA2 was increased in both AD and PD compared to the HC group (HC vs. AD, p=0.002, HC vs. PD, p=0.003), although only AD subjects exhibited increased fasting glucose (p=0.005). Furthermore, our voxel-based morphometry analysis revealed that HOMA2 was related to GMV in all cohorts in a region-specific manner (p<0.001, uncorrected). Significant relationships were observed in the medial prefrontal cortex (HC), medial temporal regions (AD), and parietal regions (PD). Finally, the directionality of the relationship between HOMA2 and GMV was disease-specific. Both HC and AD subjects exhibited negative relationships between HOMA2 and brain volume (increased HOMA2 associated with decreased brain volume), while a positive relationship was observed in PD. This cross-sectional study suggests that insulin resistance is increased in neurodegenerative disease, and that individuals with AD appear to have more severe metabolic dysfunction than individuals with PD or PD dementia.


Assuntos
Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Substância Cinzenta/patologia , Resistência à Insulina/fisiologia , Doença de Parkinson/patologia , Doença de Parkinson/fisiopatologia , Idoso , Doença de Alzheimer/tratamento farmacológico , Encéfalo/patologia , Estudos Transversais , Jejum/fisiologia , Feminino , Teste de Tolerância a Glucose , Humanos , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Atividade Motora/fisiologia , Testes Neuropsicológicos , Tamanho do Órgão , Doença de Parkinson/tratamento farmacológico
15.
Emergencias (St. Vicenç dels Horts) ; 22(2): 101-108, abr. 2010. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-97069

RESUMO

Objetivo: Analizar, en pacientes con dolor torácico de bajo riesgo, las aportaciones de la coronariografía por tomografía computarizada multidetector (TCMD) en el diagnóstico de síndrome coronario agudo (SCA). Método: Subestudio piloto descriptivo y retrospectivo de un estudio prospectivo que comparaba la rentabilidad diagnóstica de la ecografía de estrés con la angiografía por TCMD. Se realizó en una unidad de dolor torácico (UDT) que atiende a pacientes con dolor torácico no traumático. Se incluyeron, en 2008, pacientes sin coronariopatía conocida y con al menos 2 factores de riesgo coronario y dolor torácico con estudio habitual (historia clínica, electrocardiogramas, troponinas seriadas y ergometría) negativo para SCA. Se registraron datos clínicos, epidemiológicos y se les realizó una coronariografía por TCMD y, si era patológica, un cateterismo. Resultados: De los 502 pacientes con posible SCA atendidos durante la disponibilidad de la prueba, 54 (10,7%) cumplían criterios para la TCMD. La TCMD mostró coronarias normales en 35 (64,8%); en 3 (5,5%), no interpretables por artefactos; y en 16(29,6%) la TCMD fue patológica. En estos últimos, se practicaron 15 cateterismos, de los que 10 fueron patológicos. Así, la TCMD permitió el diagnóstico de SCA en un 2,0% adicional de los pacientes incluidos inicialmente en el grupo de posible SCA y el18,5% de los 54 pacientes finalmente incluidos. Conclusiones: La TCMD cardiaca aumentó el rendimiento diagnóstico de un protocolo estándar (historia clínica, electrocardiogramas y troponinas seriadas y ergometría) en los pacientes con dolor torácico (AU)


Objective: To analyze the diagnostic contribution of coronary multidetector computed tomography (CMCT) in low-riskchest pain patients. Methods: Retrospective, descriptive substudy as part of a prospective study of the diagnostic yield of stress echocardiography in comparison with CMCT angiography. The setting was a non-traumatic chest pain unit. Patients with chest pain but without diagnosed coronary artery disease and fewer than 2 coronary risk factors in 2008 were included if the information usually gathered to diagnose acute coronary syndrome (ACS) (ie, medical history, electrocardiogram, troponin series, and ergometry) was negative. Clinical and patient data were recorded and CMCT was performed; if abnormalities were detected, heart catheterism was undertaken. Results: Of the 502 patients suspected of having ACS while CMCT was available to the department, 54 (10.7%) met the criteria for performing the procedure. CMCT demonstrated normal coronary arteries in 35 (64.8%). In 3 (5.5%) the findings could not be interpreted due to artifacts and in 16 (29.6%), abnormalities were detected. Catheterization was performed in 15 of the 16 patients; the test was positive in 10. CMCT led to a diagnosis of ACS in an additional 2% of the group of patients in whom the diagnosis was initially suspected and in 18.5% of the 54 patients included in the CMCT study (AU)


Assuntos
Humanos , Tomografia Computadorizada por Raios X , Serviços Médicos de Emergência/métodos , Síndrome Coronariana Aguda/diagnóstico , Fatores de Risco , Dor no Peito/etiologia , Programas de Rastreamento/estatística & dados numéricos , Estudos Retrospectivos , Angiografia Coronária/métodos , Troponina/análise , Cateterismo Cardíaco
16.
Transplant Proc ; 40(9): 2943-5, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19010154

RESUMO

We conducted a retrospective study to evaluate the response to recombinant hepatitis B vaccine after 4 intramuscular doses (40 microg) administered at 0, 1, 2, and 6 months in 157 cirrhotic patients who were liver transplant candidates. Seventeen nonresponders were revaccinated with the same schedule. We studied the association between the following variables and the vaccine response: age, gender, etiology of cirrhosis, diabetes, severity of liver disease (Child-Pugh class and Model for End-Stage Liver Disease [MELD] score), and the number of administered doses. The response rates were: 1 dose, 40% (2/5); 2 doses, 0% (0/7); 3 doses, 32.7% (16/49); and 4 doses, 31.3% (30/96) of patients. The median hepatitis B surface antibody (anti-HBs) titer was 45 mU/mL (range, 11-620 mU/mL). The response rate to revaccination was 41.2% (median anti-HBs titer, 88 mU/mL; range, 18-190 mU/mL). Diabetics showed a lower response rate than nondiabetic patients (17.2% vs 35.3%; P = .046). No association was observed between the response rate to vaccine and the other variables. In conclusion, the response rate to hepatitis B vaccine reached a little more than 30% in cirrhotic patients who received 3 or 4 doses. No higher response rate was observed among patients who received 4 doses. Diabetes was associated with a lower response rate. Anti-HBs seroconversion rates were not associated with the other variables. Revaccination may significantly increase the response rate to hepatitis B vaccine in cirrhotic patients, and may be considered in nonresponders after the third dose. Early vaccination against HBV should be considered in such patients.


Assuntos
Vacinas contra Hepatite B/uso terapêutico , Hepatite B/imunologia , Cirrose Hepática/cirurgia , Transplante de Fígado/imunologia , Complicações do Diabetes/imunologia , Complicações do Diabetes/virologia , Relação Dose-Resposta a Droga , Feminino , Anticorpos Anti-Hepatite B/sangue , Vacinas contra Hepatite B/administração & dosagem , Humanos , Esquemas de Imunização , Cirrose Hepática/imunologia , Cirrose Hepática/patologia , Masculino , Estudos Retrospectivos
17.
Ann Dermatol Venereol ; 135(3): 209-12, 2008 Mar.
Artigo em Francês | MEDLINE | ID: mdl-18374853

RESUMO

BACKGROUND: The immunomodulatory effect of extracorporeal photochemotherapy (photopheresis) coupled with its efficacy in lymphocytic skin diseases provides a rationale for its use for erosive lichen planus. We report two cases of chronic oral erosive and corticoresistant lichen planus successfully treated with photopheresis. PATIENTS AND METHODS: Case 1. A 61-years-old man had erosive oral lichen planus for four years. Oral steroids were contra-indicated due to iatrogenic pancreatitis. After nine photopheresis sessions, subjective improvement occurred and the oral lesions were stabilized. Case 2. A 17-years-old woman presented corticodependent oral and genital erosive lichen planus and cutaneous lesions. After seven sessions of photopheresis, the patient was able to eat again and the pain decreased. After 20 sessions, the cutaneous lichen planus disappeared and complete remission of the mucous lesions was obtained without corticotherapy. DISCUSSION: These two cases, together with 23 other cases reported elsewhere, strongly suggested the value of photopheresis in the treatment of erosive lichen planus. However, relapses after treatment withdrawal appear extremely frequent.


Assuntos
Corticosteroides , Líquen Plano Bucal/tratamento farmacológico , Adolescente , Contraindicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/efeitos dos fármacos , Mucosa Bucal/patologia , Pancreatite/complicações , Fotoferese
18.
Phys Rev Lett ; 98(22): 229601; discussion 229602, 2007 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-17677886
19.
Radiologia ; 49(4): 227-35, 2007.
Artigo em Espanhol | MEDLINE | ID: mdl-17594881

RESUMO

Arrhythmia or altered heart rhythms can present with or without underlying heart disease. Most cardiopathies give rise to arrhythmias; however, arrhythmias can also be caused in previously healthy hearts by other conditions such as metabolic disorders, electrolyte imbalances, and drug use or abuse. The clinical presentation can range from asymptomatic cases discovered incidentally on routine examination to sudden death as the only clinical sign. In cases with clinical suspicion of arrhythmia, Holter and electrophysiological studies should be performed. If the condition is confirmed, associated cardiopathy must be ruled out. Echocardiography should be the first imaging test to be performed. Multidetector computed tomography (CT) and magnetic resonance imaging (MRI) have been applied to the field of cardiology more recently and are gradually acquiring specific roles with precise indications. In the study of arrhythmias, MRI is indicated in two particular areas: auricular fibrillation and arrhythmogenic right ventricular dysplasia.


Assuntos
Fibrilação Atrial/diagnóstico , Imageamento por Ressonância Magnética , Displasia Arritmogênica Ventricular Direita/diagnóstico , Humanos , Radiologia
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