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1.
Crit Rev Food Sci Nutr ; 62(3): 656-669, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33021382

RESUMEN

The burden of malnutrition in Africa calls for deeper exploration of underutilized species which are rich in nutrients and have the potential to reduce food and nutrition insecurity. The common staple crops are not able to meet daily requirements for both macro- and micro-nutrients. In order to lessen this burden; protein, calorie and micronutrient deficiencies must be properly addressed for optimal growth and development to be attained. African indigenous underutilized vegetables can play a significant role in the food security of vulnerable groups like under-five children and women in both urban and rural settings. The potential of grain amaranth in meeting the nutrition needs of humans has remained a subject of interest in scientific research. Amaranth is considered one of the most commonly produced and consumed indigenous vegetables on the African continent with high nutritional potentials but yet to be fully exploited. This review therefore aims at discussing the current knowledge of the inherent potentials of grain amaranths, its current application in the food industry and proposes a framework for actions and partnerships required to scale up and improve amaranth value chain.


Asunto(s)
Amaranthus , Desnutrición , Niño , Grano Comestible , Humanos , Desnutrición/prevención & control , Estado Nutricional , Verduras
2.
Dermatol Online J ; 26(5)2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32621699

RESUMEN

We present an adult woman with subcutaneous nodules without any signs or symptoms of rheumatoid arthritis. These nodules are believed to be pseudorheumatoid nodules, which are considered a deep form of granuloma annulare. This case is unique because these are typically found in children and have rarely been reported in adults. These nodules are typically asymptomatic and do not require treatment. However, attempts have been made to treat them with intralesional corticosteroids, cryotherapy, or excision. Owing to the fact that this is considered a deep form of granuloma annulare, they are sometimes treated similarly with a combination of monthly rifampin, ofloxacin, and minocycline.


Asunto(s)
Granuloma Anular/patología , Adulto , Diagnóstico Diferencial , Femenino , Granuloma Anular/diagnóstico , Humanos , Nódulo Reumatoide/diagnóstico , Piel/patología
3.
J Hum Nutr Diet ; 33(2): 241-251, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31680361

RESUMEN

BACKGROUND: In developing countries such as Nepal, many children aged below 3 years do not grow at a sufficiently high rate and are vulnerable to micronutrient deficiencies (e.g. vitamin A). Challenges to child nutrition can result from poverty, unhealthy traditional practices, inadequate caring and feeding practices. The present study aimed to assess the feeding practices of pre-school children and their associated factors. METHODS: A cross-sectional study was carried out in pre-schools located in Kathmandu district between February and March 2018. Three levels in terms of price range (lower, medium and higher level) of pre-schools were selected to reach the mothers of children aged ≤3 years. A structured questionnaire was administered to 145 mothers. Descriptive analyses were conducted to observe the characteristics of the population. Multinomial logistic regression analyses were performed to identify the association for the factors of mothers' perception of their current feeding practices. RESULTS: We found that dal-bhat/jaulo was a common complementary food irrespective of socio-economic background. Interestingly, mothers who had received a higher education were significantly less likely to change their feeding practices (odds ratio = 0.118, confidence interval = 0.01-0.94). The mothers that fed a higher quantity porridge to their children showed a high willingness to change the feeding practices. CONCLUSIONS: Poor feeding practices are still an important public health problem in Nepal and were observed to be associated with low socio-economic status, unawareness and a lack of knowledge towards dietary diversity combined with strong beliefs related to social forces and cultures.


Asunto(s)
Trastornos de la Nutrición del Niño/epidemiología , Dieta Saludable/estadística & datos numéricos , Conducta Alimentaria/psicología , Madres/estadística & datos numéricos , Pobreza/estadística & datos numéricos , Trastornos de la Nutrición del Niño/etiología , Preescolar , Estudios Transversales , Encuestas sobre Dietas , Dieta Saludable/psicología , Escolaridad , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Modelos Logísticos , Masculino , Madres/psicología , Nepal/epidemiología , Oportunidad Relativa , Pobreza/psicología , Clase Social , Encuestas y Cuestionarios
4.
Animal ; 11(1): 131-139, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27353419

RESUMEN

Machine vision-based monitoring of pig lying behaviour is a fast and non-intrusive approach that could be used to improve animal health and welfare. Four pens with 22 pigs in each were selected at a commercial pig farm and monitored for 15 days using top view cameras. Three thermal categories were selected relative to room setpoint temperature. An image processing technique based on Delaunay triangulation (DT) was utilized. Different lying patterns (close, normal and far) were defined regarding the perimeter of each DT triangle and the percentages of each lying pattern were obtained in each thermal category. A method using a multilayer perceptron (MLP) neural network, to automatically classify group lying behaviour of pigs into three thermal categories, was developed and tested for its feasibility. The DT features (mean value of perimeters, maximum and minimum length of sides of triangles) were calculated as inputs for the MLP classifier. The network was trained, validated and tested and the results revealed that MLP could classify lying features into the three thermal categories with high overall accuracy (95.6%). The technique indicates that a combination of image processing, MLP classification and mathematical modelling can be used as a precise method for quantifying pig lying behaviour in welfare investigations.


Asunto(s)
Conducta Animal/fisiología , Procesamiento de Imagen Asistido por Computador/métodos , Actividad Motora/fisiología , Porcinos/fisiología , Grabación en Video/métodos , Animales
5.
Water Sci Technol ; 58(4): 781-7, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18776612

RESUMEN

Much research has asserted that high shear forces are necessary for the formation of aerobic granular sludge in Sequencing Batch Reactors (SBRs). In order to distinguish the role of shear and dissolved oxygen on granule formation, two separate experiments were conducted with three bench-scale SBRs. In the first experiment, an SBR was operated with five sequentially decreasing superficial upflow gas velocities ranging from 1.2 to 0.4 cm s(-1). When less than 1 cm s(-1) shear was applied to the reactor, aerobic granules disintegrated into flocs, with corresponding increases in SVI and effluent suspended solids. However, the dissolved oxygen also decreased from 8 mg L(-1) to 5 mg L(-1), affecting the Feast/Famine regime in the SBR and the substrate removal kinetics. A second experiment operated two SBRs with an identical shear force of 1.2 cm s(-1), but two dissolved oxygen concentrations. Even when supplied a high shear force, aerobic granules could not form at a dissolved oxygen less than 5 mg L(-1), with a Static Fill. These results indicate that the substrate removal kinetics and dissolved oxygen are more significant to granule formation than shear force.


Asunto(s)
Reactores Biológicos/microbiología , Oxígeno/metabolismo , Aguas del Alcantarillado/microbiología , Aerobiosis , Biodegradación Ambiental , Cinética , Aguas del Alcantarillado/química
6.
Br J Clin Pharmacol ; 62(6): 666-72, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17040470

RESUMEN

AIM: To evaluate a context-learning pharmacotherapy programme for approximately 750 2nd, 3rd and 4th year preclinical medical students with respect to mastering cognitive pharmacotherapeutic skills, i.e. choosing a (drug) treatment and determining patient information. METHODS: The context-learning pharmacotherapy programme consists of weekly organized role play sessions in the form of consulting hours. Fourth year students sit for a therapeutic Objective Structured Clinical Examination (OSCE) in the form of consulting hours at the outpatient clinic. Sixty-one 2nd, 74 3rd and 49 4th year medical students who attended the role play sessions and the OSCE were randomly selected. Their performances were assessed by clinical examiners and clinical experts and compared with a reference group of 6th year graduated students. Additionally, the scores of a questionnaire on study load and appreciation were collected. RESULTS: The level of the pharmacotherapeutic skills of the 4th year students who followed the pharmacotherapy context-learning programme was not far below that of 6th year graduates who had finished their clinical clerkships, but had not followed the pharmacotherapy programme. The time spent on the programme was about 1% of the total study load per year. The students appreciated the role play sessions and OSCE by around 80% and 99% of the maximum possible scores. CONCLUSIONS: Preclinical pharmacotherapy context learning has a modest but positive effect on learning cognitive pharmacotherapeutic skills, i.e. choosing a drug treatment and determining patient information. This effect has been obtained with role play sessions, a suboptimal form of context learning, with a minimal study load and a high appreciation by students.


Asunto(s)
Educación Médica/métodos , Farmacología/educación , Adulto , Competencia Clínica , Humanos , Solución de Problemas , Evaluación de Programas y Proyectos de Salud , Estudiantes de Medicina/psicología
7.
Biochimie ; 88(6): 645-50, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16460863

RESUMEN

BACKGROUND: Under conditions of iron overload non-transferrin-bound iron (NTBI) occurs in the circulation and is mainly cleared by the liver. Beside iron, gallium and aluminum enhance accumulation of NTBI. We try to characterize the mechanism and metal-mediated regulation of NTBI uptake using cultivated primary rat hepatocytes. METHODS: Hepatocytes from rat liver were incubated with 0.1 mg/ml transferrin (as control), with ferric ammonium citrate or other di- and trivalent metal salts and the uptake of (55)Fe-labeled Fe-diethylene triammine pentaacetate was measured. RESULTS: Uptake rates for iron increased from 0.3 to 2.1 pmol/mg protein per min in cells preincubated for 5 hours with 300 microM ferric ammonium citrate, to 1.7 pmol/mg protein per min with gallium and to 1.2 pmol/mg protein per min with aluminum. Maximal stimulation was obtained with 300 microM iron and 600 microM gallium. Preincubation with divalent metals was ineffective. NTBI uptake was specific for iron, partly inhibited by gallium citrate, diferric transferrin and completely inhibited by apotransferrin in control and gallium-treated cells. In iron-loaded cells, inhibition of NTBI uptake by diferric transferrin completely disappeared within 2 hours. CONCLUSIONS: These experiments show that hepatocytes do respond to the presence of trivalent metals by an increased transport capacity to sequester these ions. The metals seem to have at least partly different mechanisms of transport stimulation.


Asunto(s)
Citratos/farmacología , Galio/farmacología , Hepatocitos/efectos de los fármacos , Hierro/metabolismo , Animales , Transporte Biológico/efectos de los fármacos , Cationes/química , Compuestos Férricos/farmacología , Hepatocitos/metabolismo , Hígado/citología , Hígado/efectos de los fármacos , Masculino , Compuestos de Amonio Cuaternario/farmacología , Ratas , Ratas Sprague-Dawley , Especificidad por Sustrato
8.
Eur J Clin Invest ; 35(11): 711-7, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16269021

RESUMEN

BACKGROUND: Friedreich's ataxia (FRDA) is a neurodegenerative disorder caused by decreased expression of the protein frataxin, recently described to be an iron chaperone for the assembly of iron-sulphur clusters in the mitochondria, causing iron accumulation in mitochondria, oxidative stress and cell damage. Searching for compounds that could possibly influence frataxin expression, we found that the cytokine recombinant human erythropoietin (rhuEPO) significantly increases frataxin expression by a still unknown mechanism. MATERIALS AND METHODS: Isolated lymphocytes from FRDA patients, isolated human cardiac cells (fibroblasts and myocytes) from patients undergoing heart transplantation and P19 mouse cells (neuronal typ), were incubated with different concentrations of rhuEPO, and immunoblot was carried out for the detection of frataxin. RESULTS: We show for the first time that the cytokine recombinant human erythropoietin (rhuEPO) can, additionally to its reported neuro- and cardioprotective properties, increase frataxin expression in vitro. We show that rhuEPO significantly increases frataxin expression in primary lymphocytes from patients with Friedreich's ataxia. Further we show that rhuEPO can also increase frataxin expression in many other cell types; among them the most affected cell types in FRDA such as neurones and cardiac cells. CONCLUSIONS: Our results provide a scientific basis for further studies examining the effectiveness of this agent for the treatment of FRDA patients.


Asunto(s)
Eritropoyetina/uso terapéutico , Ataxia de Friedreich/tratamiento farmacológico , Proteínas de Unión a Hierro/análisis , Línea Celular , Células Cultivadas , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Humanos , Linfocitos/efectos de los fármacos , Linfocitos/metabolismo , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Proteínas Recombinantes , Frataxina
9.
Eur Heart J ; 23(11): 886-91, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12042010

RESUMEN

AIMS: To compare the precursor of atrial and brain natriuretic peptide (N-ANP, N-BNP), brain natriuretic peptide (BNP), big endothelin-1, the 6-min walk test and the Minnesota Living with Heart Failure Questionnaire (LHFQ) with regard to short-term outcome in an ambulatory heart failure population. METHODS AND RESULTS: Ninety-six individuals (left ventricular ejection fraction of 26+/-10%) were included in the study. Within 1 day blood samples of N-ANP, N-BNP, BNP and big endothelin-1 were obtained, and the 6-min walk test and LHFQ were measured. The predictive power of these variables - including renin-angiotensin system antagonist therapy - in respect of 1-year event-free survival were calculated with a Cox regression analysis. All investigated variables had the power to predict outcome in a univariate analysis. Multivariate analysis revealed that N-ANP (chi-square=58 P<0.0001), BNP (chi-square=8 P<0.01), the LHFQ (chi-square=6 P<0.02) and the renin-angiotensin system antagonist (chi-square=4 P<0.05), are independent predictors. CONCLUSION: We conclude that, in an open clinical cohort of patients with large differences in the progression of the disease, N-ANP, BNP and LHFQ are the most reliable predictors of worsening heart failure in the short term. However, the dosage of the ACE inhibitor influenced short-term survival in this population.


Asunto(s)
Insuficiencia Cardíaca/epidemiología , Actividades Cotidianas , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Factor Natriurético Atrial/metabolismo , Estudios de Cohortes , Endotelina-1 , Endotelinas/metabolismo , Femenino , Insuficiencia Cardíaca/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Péptido Natriurético Encefálico/metabolismo , Valor Predictivo de las Pruebas , Pronóstico , Modelos de Riesgos Proporcionales , Precursores de Proteínas/metabolismo , Encuestas y Cuestionarios , Caminata
11.
Int J Cardiovasc Imaging ; 17(4): 279-86, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11599867

RESUMEN

The goal of this research was to develop an automated algorithm for tracking the borders of the left ventricle (LV) in a cine-MRI gradient-echo temporal data set. The algorithm was validated on four patient populations: healthy volunteers and patients with dilated cardiomyopathy (DCM), left ventricular hypertrophy (LVH), or left ventricular aneurysm (LVA). A full tomographic set (approximately 11 slices/case) of short-axis images through systole was obtained for each patient. Initial endocardial and epicardial contours for the end-diastolic (ED) and end-systolic (ES) frames were manually traced on the computer by an experienced radiologist. The ED tracings were used as the starting point for the algorithm. The borders were tracked through each phase of the temporal data set, until the ES frame was reached (approximately 7 phases/slice). Peak gradients along equally spaced chords calculated perpendicular to a centerline determined midway between the endocardial and epicardial borders were used for border detection. This approach was tested by comparing the LV epicardial and endocardial volumes calculated at ES to those based on the manual tracings. The results of the algorithm compared favorably with both the endocardial (r2 = 0.72 - 0.98) and epicardial (r2 = 0.96 - 0.99) volumes of the tracer.


Asunto(s)
Algoritmos , Procesamiento Automatizado de Datos , Corazón/diagnóstico por imagen , Imagen por Resonancia Magnética , Humanos , Radiografía , Análisis de Regresión , Volumen Sistólico/fisiología , Función Ventricular Izquierda/fisiología
12.
J Am Coll Cardiol ; 38(2): 436-42, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11499735

RESUMEN

OBJECTIVES: The study assessed the relative predictive potency of neurohumoral factors in patients with advanced left ventricular (LV) dysfunction during neurohumoral blocking therapy. BACKGROUND: The course of heart failure is characterized by progressive LV deterioration associated with an increase in cardiac (natriuretic peptides) and predominantly extracardiac (norepinephrine, big endothelin [big ET]) hormone plasma levels. METHODS: Plasma hormones were measured at baseline and months 3, 6, 12 and 24 in 91 patients with heart failure (left ventricular ejection fraction [LVEF] <25%) receiving 40 mg enalapril/day and double-blind atenolol (50 to 100 mg/day) or placebo. After the double-blind study phase, patients were followed up to four years. Stepwise multivariate regression analyses were performed with 10 variables (age, etiology, LVEF, symptom class, atenolol/placebo, norepinephrine, big ET, log aminoterminal atrial natriuretic peptide, log aminoterminal B-type natriuretic peptide [N-BNP] and log B-type natriuretic peptide [BNP]). During the study, the last values prior to patient death were used, and in survivors the last hormone level, New York Heart Association class and LVEF at month 24 were used. RESULTS: Thirty-one patients died from a cardiovascular cause during follow-up. At baseline, log BNP plasma level (x2 = 13.9, p = 0.0002), treatment allocation (x2 = 9.5, p = 0.002) and LVEF (x2 = 5.6, p = 0.017) were independently related to mortality. During the study, log BNP plasma level (x2 = 21.3, p = 0.0001) remained the strongest predictive marker, with LVEF (x2 = 11.2, p = 0.0008) log N-BNP plasma level (x2 = 8.9, p = 0.0027) and treatment allocation (x2 = 6.4, p = 0.0109) providing additional independent information. CONCLUSIONS: In patients with advanced LV dysfunction receiving high-dose angiotensin-converting enzyme inhibitors and beta-blocker therapy BNP and N-BNP plasma levels are both independently related to mortality. This observation highlights the importance of these hormones and implies that they will likely emerge as a very useful blood test for detection of the progression of heart failure, even in the face of neurohumoral blocking therapy.


Asunto(s)
Antagonistas Adrenérgicos beta/uso terapéutico , Atenolol/uso terapéutico , Hormonas/sangre , Disfunción Ventricular Izquierda/tratamiento farmacológico , Disfunción Ventricular Izquierda/mortalidad , Factor Natriurético Atrial/sangre , Biomarcadores/sangre , Método Doble Ciego , Endotelina-1 , Endotelinas/sangre , Femenino , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Norepinefrina/sangre , Placebos , Pronóstico , Modelos de Riesgos Proporcionales , Precursores de Proteínas/sangre , Distribución Aleatoria , Factores de Riesgo , Tasa de Supervivencia , Resultado del Tratamiento , Disfunción Ventricular Izquierda/sangre
14.
Am J Phys Med Rehabil ; 80(3): 206-14; quiz 215-6, 224, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11237275

RESUMEN

OBJECTIVE: To determine the impact of an 8-wk neuromuscular stimulation program of thigh muscles on strength and cross-sectional area in patients with refractory heart failure listed for transplantation. DESIGN: Forty-two patients with a stable disease course were assigned randomly to a stimulation group (SG) or a control group (CG). The stimulation protocol consisted of biphasic symmetric impulses with a frequency of 50 Hz and an on/off regime of 2/6 sec. RESULTS: Primary outcome measures were isometric and isokinetic thigh muscle strength and muscle cross-sectional area. Our results showed an increase of muscle strength by mean 22.7 for knee extensor and by 35.4 for knee flexor muscles. The CG remained unchanged or decreased by -8.4 in extensor strength. Cross-sectional area increased in the SG by 15.5 and in the CG by 1.7. CONCLUSIONS: Activities of daily living as well as quality of life increased in the SG but not in the CG. Subscales of the SF-36 increased significantly in the SG, especially concerning physical functioning by +7.5 (1.3-30.0), emotional role by +33.3 (0-66.6), and social functioning by +18.8 (0-46.9), all P < 0.05. Neither a change nor a decrease was observed in the CG. Neuromuscular electrical stimulation of thigh muscles in patients with refractory heart failure is effective in increasing muscle strength and bulk and positively affects the perception of quality of life and activities of daily living.


Asunto(s)
Terapia por Estimulación Eléctrica/métodos , Insuficiencia Cardíaca/complicaciones , Debilidad Muscular/etiología , Debilidad Muscular/rehabilitación , Atrofia Muscular/etiología , Atrofia Muscular/rehabilitación , Muslo , Actividades Cotidianas , Enfermedad Crónica , Emociones , Tolerancia al Ejercicio , Femenino , Trasplante de Corazón , Humanos , Contracción Isométrica , Contracción Isotónica , Masculino , Persona de Mediana Edad , Debilidad Muscular/diagnóstico , Debilidad Muscular/fisiopatología , Debilidad Muscular/psicología , Atrofia Muscular/diagnóstico , Atrofia Muscular/fisiopatología , Atrofia Muscular/psicología , Calidad de Vida , Método Simple Ciego , Conducta Social , Resultado del Tratamiento , Listas de Espera
15.
Cardiovasc Res ; 49(2): 308-18, 2001 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-11164841

RESUMEN

OBJECTIVE: To quantify regional three-dimensional (3D) motion and myocardial strain using magnetic resonance (MR) tissue tagging in patients with non-ischemic dilated cardiomyopathy (DCM). METHODS: MR grid tagged images were obtained in multiple short- and long-axis planes in thirteen DCM patients. Regional 3D displacements and strains were calculated with the aid of a finite element model. Five of the patients were also imaged after LV volume reduction by partial left ventriculectomy (PLV), combined with mitral and tricuspid valve repair. RESULTS: DCM patients showed consistent, marked regional heterogeneity. Systolic lengthening occurred in the septum in both circumferential (%S(C) -5+/-7%) and longitudinal (%S(L) -2+/-5%) shortening components (negative values indicating lengthening). In contrast, the lateral wall showed relatively normal systolic shortening (%S(C) 12+/-6% and %S(L) 6+/-5%, P<0.001 lateral vs. septal walls). A geometric estimate of regional stress was correlated with shortening on a regional basis, but could not account for the differences in shortening between regions. In the five patients imaged post-PLV, septal function recovered (%S(C) 9+/-5%,%S(L) 6+/-5%, P<0.02 pre vs. post) with normalization of wall stress, whereas lateral wall shortening was reduced (%S(C) 7+/-6%,%S(L) 3+/-3%, P<0.02 pre vs. post) around the site of surgical resection. CONCLUSIONS: A consistent pattern of regional heterogeneity of myocardial strain was seen in all patients. Reduced function may be related to increased wall stress, since recovery of septal function is possible after PLV. However, simple geometric stress determinants are not sufficient to explain the functional heterogeneity observed.


Asunto(s)
Cardiomiopatía Dilatada/fisiopatología , Simulación por Computador , Corazón/fisiopatología , Procesamiento de Imagen Asistido por Computador , Modelos Cardiovasculares , Adulto , Anciano , Análisis de Varianza , Cardiomiopatía Dilatada/cirugía , Femenino , Enfermedades de las Válvulas Cardíacas/cirugía , Ventrículos Cardíacos/cirugía , Humanos , Imagen por Resonancia Cinemagnética , Masculino , Persona de Mediana Edad , Estrés Mecánico , Función Ventricular
16.
Eur J Heart Fail ; 2(4): 407-12, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11113718

RESUMEN

BACKGROUND: The survival benefit of beta-blocker treatment in patients with heart failure has been established in recent trials. Yet, the impact of beta-blockers added on high dose angiotensin converting enzyme inhibitors has not been reported. AIMS: To investigate the effect of atenolol, a hydrophilic, selective beta1-adrenergic antagonist, added on enalapril 40 mg/day in patients with advanced left ventricular dysfunction in a double-blind placebo-controlled trial. METHODS: One hundred and nineteen patients with class II or III heart failure, left ventricular ejection fraction < or = 25% and treatment with 40 mg enalapril daily were given an initial challenge dose of atenolol 12. 5 mg. One hundred patients (54 with idiopathic, 28 with ischemic, 18 with other dilated cardiomyopathy) tolerated challenge and were randomized to atenolol (maintenance dose 89+/-11 mg/day, range 50-100 mg/day) or placebo. The primary endpoint was combined worsening heart failure or death within 2 years, the secondary endpoint was hospitalization for cardiac events. RESULTS: After 395+/-266 days interim analysis revealed a significant difference between the atenolol and placebo group (log rank P<0.01) and the trial was concluded. Twenty-seven patients had developed worsening heart failure (8 in the atenolol group vs. 19 in the placebo group) and 13 patients had died (5 in the atenolol vs. 8 in the placebo group). Overall there were 23 hospitalizations for cardiac events (6 in the atenolol group vs. 21 in the placebo group, P=0.07); 17 hospitalizations were due to worsening heart failure (5 in the atenolol group, 12 in the placebo-group, P=0.05) and 10 due to arrhythmias (1 in the atenolol group vs. 9 in the placebo group, P<0.01) CONCLUSIONS: The data suggest that in patients with advanced left ventricular dysfunction, beta-blockers can provide substantial benefits supplementary to that already achieved with high dose enalapril treatment.


Asunto(s)
Antagonistas Adrenérgicos beta/uso terapéutico , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Atenolol/uso terapéutico , Enalapril/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Inhibidores de la Enzima Convertidora de Angiotensina/administración & dosificación , Progresión de la Enfermedad , Método Doble Ciego , Enalapril/administración & dosificación , Femenino , Insuficiencia Cardíaca/mortalidad , Hospitalización/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Selección de Paciente
17.
IEEE Trans Biomed Eng ; 47(11): 1476-86, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11077741

RESUMEN

Leakage of electric current through cardiac structures surrounding the ventricle is a primary source of error during ventricular volume measurements using a conductance catheter. This error can be represented as a leakage volume, VL. VL is generally estimated by a saline-bolus method, and is assumed constant throughout the cardiac cycle. However, dynamic changes in ventricular volume and cardiac wall thickness could change VL. To estimate VL, a dynamic finite element model of the heart was developed based on MR images. Conductance measurements were simulated using a modeled conductance catheter, and true VL was calculated. VL varied from 22.7 ml (end-systole) to 26.4 ml (end-diastole) in the left ventricle and from 19.9 ml (end-systole) to 26.9 ml (end-diastole) in the right ventricle. The saline-bolus method underestimated VL in both the left (VL = 19.4 ml) and the right (VL = 4.1 ml) ventricular volume measurements. VL increased linearly with the ratio of blood to tissue resistivity, and changed minimally with catheter position. These results indicate that VL has to be estimated dynamically throughout the cardiac cycle to obtain accurate cardiac volume measurements. The results also show that the saline bolus method does not estimate current leakage accurately, especially in the right ventricular volume measurement.


Asunto(s)
Corazón/anatomía & histología , Corazón/fisiología , Modelos Cardiovasculares , Ingeniería Biomédica , Simulación por Computador , Conductividad Eléctrica , Electrofisiología , Ventrículos Cardíacos/anatomía & histología , Humanos , Modelos Anatómicos , Función Ventricular
18.
J Heart Lung Transplant ; 19(10): 939-45, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11044687

RESUMEN

BACKGROUND: Selection of patients for urgent heart transplantation who have end-stage heart failure requires objective criteria to distinguish between subjects who may deteriorate clinically and those who can be stabilized. This population appears to differ in terms of right ventricular function, and right ventricular changes in loading may provide prognostic information. To investigate predictive parameters of patients admitted for urgent heart transplantation, we prospectively studied the mechanical performance of the right ventricle during acute afterload reduction. PATIENTS AND METHODS: We studied 68 heart failure patients hospitalized for bridge-to-transplant. The patients underwent right heart catherization at baseline and during prostaglandin E1 infusion. We stratified patients according to clinical outcome: Group A comprised patients who could be weaned from bridging therapy or who were electively transplanted after at least 90 days, and Group B comprised patients who died or who remained unstable and required transplant under urgent conditions. RESULTS: Right ventricular hemodynamics at baseline were comparable in both groups. However, during maximal vasodilatation, with prostaglandin E1 infusion, the right ventricular end-diastolic volume index (EDVI) was significantly reduced in Group A, (-23 ml/m(2) (p < 0.01) vs +12 ml/m(2) (p = n.s. DeltaEDVI in Group B. Reduction of EDVI by less than 10% during prostaglandin E1 infusion has a sensitivity of 89% and a specificity of 70% for clinical deterioration. CONCLUSIONS: The response of right ventricular volumes to prostaglandin E1 may predict the outcome of patients with severe congestive heart failure listed for urgent heart transplantation.


Asunto(s)
Alprostadil/uso terapéutico , Insuficiencia Cardíaca/fisiopatología , Vasodilatadores/uso terapéutico , Función Ventricular Derecha , Anciano , Femenino , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/cirugía , Hemodinámica/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Selección de Paciente , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos
19.
Scand J Rehabil Med ; 31(4): 223-8, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10599899

RESUMEN

The aim of this study was to evaluate the impact of a three-month exercise program on the perception of quality of life in patients with severe chronic heart failure. In a randomized controlled setting, 27 patients with a left ventricular ejection fraction of 18.1 +/- 8.0% were entered into the study. The training group performed aerobic exercises for three hours/week while the control group continued their usual activities of daily living. Quality of life was measured using the German version of the MOS SF-36. Two patients required a change in their drug regimen and were therefore withdrawn from the study. Twenty-five patients completed the study. In the exercise group the perception of quality of life improved significantly in the domains of vitality (p = 0.0001), physical role fulfillment (p = 0.001), physical (p = 0.02) and social (p = 0.0002) functioning. Exercise was effective in increasing peak oxygen uptake and exercise time (p < 0.01). Only weak correlations were registered between parameters of physical performance and quality of life domains. The results of the study indicate that aerobic exercise can improve the perception of quality of life in patients with severe chronic heart failure.


Asunto(s)
Terapia por Ejercicio/métodos , Insuficiencia Cardíaca/psicología , Insuficiencia Cardíaca/rehabilitación , Calidad de Vida , Enfermedad Crónica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Psicometría , Estadísticas no Paramétricas , Encuestas y Cuestionarios , Factores de Tiempo , Resultado del Tratamiento
20.
Arch Phys Med Rehabil ; 80(7): 746-50, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10414756

RESUMEN

OBJECTIVE: To evaluate whether a specific program of moderate-intensity step aerobics training may be sufficient to improve the exercise tolerance of patients with severe chronic heart failure. PATIENTS: Twenty-six patients (22 men, 4 women; mean +/- SD age, 54 +/- 9yrs) with a history of severe chronic heart failure (left ventricular ejection fraction of 18% +/- 8%). STUDY DESIGN: Prospective, randomized, controlled trial. Patients were randomized into exercise and control groups. All patients underwent a clinical examination and a ramp pattern cycle exercise test before and after the observation period. The exercise group underwent a moderate-intensity (50% of peak oxygen uptake) 12-week training program, progressing to 100 minutes per week of step aerobics and 50 minutes per week of cycling. The control group did not perform a training program. MAIN OUTCOME MEASURES: Peak oxygen uptake, peak workload, percent of predicted power ability. RESULTS: Significant increases in peak oxygen uptake (15 +/- 3.4 to 18.5 +/- 2.9mL/kg/min; p = .001), peak workload (77 +/- 26 to 99 +/- 31 watts; p = .000), and percent of predicted power ability (43% +/- 10% to 56% +/- 13%; p = .000) were observed in the exercise group. No significant changes in baseline parameters occurred in the control group. There were no critical changes in heart rate or blood pressure in either group. CONCLUSION: Moderate-intensity step aerobics training significantly increases peak oxygen uptake and peak workloads in patients with severe chronic heart failure.


Asunto(s)
Terapia por Ejercicio/métodos , Insuficiencia Cardíaca/rehabilitación , Anciano , Enfermedad Crónica , Prueba de Esfuerzo , Tolerancia al Ejercicio , Femenino , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/metabolismo , Insuficiencia Cardíaca/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Consumo de Oxígeno , Evaluación de Programas y Proyectos de Salud , Estudios Prospectivos , Método Simple Ciego , Volumen Sistólico
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