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OBJECTIVE: To determine whether serum B-type natriuretic peptide measured at rest and peak exercise and DeltaBNP contribute to the predictive value and diagnostic accuracy of exercise test in the diagnosis of myocardial ischemia. BACKGROUND: Ventricular myocytes release BNP in response to increased wall stress that occurs in acute ischemia. During exercise testing, transient myocardial ischemia could also cause acute myocardial stress and changes in circulating BNP. METHODS: BNP was measured before and immediately after exercise testing with radionuclide imaging in 203 consecutive subjects referred for chest pain evaluation. Tested subjects were classified as ischemic and non-ischemic based on exercise results, and no ischemia, mild-moderate, and severe ischemia according to perfusion scan results. A logistic regression model, constructed of an ROC and an AUC (area under the curve), was used. RESULTS: Ischemic ECG changes (> or =1 mm, horizontal S-T shift) were detected in the treadmill exercise test in 127 subjects (62.6%), and 76 (37.4%) had neither ST segment shift nor chest pain. Baseline BNP was higher in the ischemic group compared to the non-ischemic group (p=0.044); peak BNP was also higher in the ischemic group (p=0.025), as was DeltaBNP (p=0.0126). Of these 127 subjects, 106 (52% of all) had abnormal perfusion scan results. In the ischemic group, the median baseline, peak exercise BNP, and DeltaBNP values from baseline to peak were higher than in the non-ischemic group. In the severe ischemic group these variables were approximately three-fold higher than in the mild-moderate ischemic group (p<0.0001 for baseline; p<0.0001 for peak; and p<0.0001 for DeltaBNP). Rest, peak exercise, and DeltaBNP values were significantly higher in patients with previous myocardial infarction (p<0.001) and in patients treated with beta blockers; peak exercise BNP was higher in hypertensives and diabetics (p<0.05). The ROC convergence model showed that the AUC for peak-exercise BNP was best able to discriminate and predict severe ischemia and no ischemia, while DeltaBNP from rest to peak exercise discriminated best between mild-moderate and severe ischemia. CONCLUSIONS: Peak exercise BNP and DeltaBNP improved the sensitivity, specificity, positive likelihood ratio, predictive value, and diagnostic accuracy of severe ischemia detection during an exercise test. The contribution of BNP determination during exercise was, however, less impressive than previously reported by others.
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Isquemia Miocárdica/sangre , Isquemia Miocárdica/diagnóstico por imagen , Péptido Natriurético Encefálico/sangre , Tomografía Computarizada de Emisión de Fotón Único , Anciano , Biomarcadores/sangre , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Esfuerzo Físico , Valor Predictivo de las Pruebas , Radiofármacos , Reproducibilidad de los Resultados , Descanso , Sensibilidad y Especificidad , Tecnecio Tc 99m SestamibiAsunto(s)
Pediatría , Rehabilitación , Animales , Niño , Desarrollo Infantil , Humanos , Recuperación de la FunciónRESUMEN
We use an unconditionally stable numerical scheme to implement a fast version of the geodesic active contour model. The proposed scheme is useful for object segmentation in images, like tracking moving objects in a sequence of images. The method is based on the Weickert-Romeney-Viergever (additive operator splitting) AOS scheme. It is applied at small regions, motivated by the Adalsteinsson-Sethian level set narrow band approach, and uses Sethian's (1996) fast marching method for re-initialization. Experimental results demonstrate the power of the new method for tracking in color movies.
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This project has been concerned with the comparison of children born as a result of fresh embryo transfer (IVF) with children conceived and born via the natural process. The former included children who were the single outcome of the birth (singletons) and children who were the result of a multiple birth (e.g. twins, triplets). A computer database was established into which was put 23 items of data on each child, making a total of 12,788 items overall. There were 278 "normally conceived" children (controls), 150 IVF Singletons, and 128 children from multiple births. The results show interesting differences in the gestational age at birth, the birth weight, the mode of delivery and the degrees of birth abnormalities and malformations.
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Transferencia de Embrión , Fertilización In Vitro , Cómputos Matemáticos , Resultado del Embarazo , Embarazo Múltiple , Peso al Nacer , Anomalías Congénitas/epidemiología , Bases de Datos Factuales , Transferencia de Embrión/estadística & datos numéricos , Femenino , Fertilización In Vitro/estadística & datos numéricos , Edad Gestacional , Humanos , Recién Nacido , Embarazo , Embarazo Múltiple/estadística & datos numéricosRESUMEN
We formulate and address the problem of planning a pushing manipulation by a mobile robot which tries to rearrange several movable objects in its work space. We present an algorithm which, when given a set of goal configurations, plans a pushing path to the "cheapest" goal or announces that no such path exists. Our method provides detailed manipulation plans, including any intermediate motion of the pusher while changing contact configuration with the pushed movables. Given a pushing problem, a pushing path is found using a two-phase procedure: a context sensitive back propagation of a cost function which maps the configuration space, and a gradient descent phase which builds the pushing path. Both phases are based on a dynamic neighborhood filter which constrains each step to consider only admissible neighboring configurations. This admissibility mechanism provides a primary tool for expressing the special characteristics of the pushing manipulation. It also allows for a full integration of any geometrical constraints imposed by the pushing robot, the pushed movables and the environment. We prove optimality and completeness of our algorithm and give some experimental results in different scenarios.
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AIMS: To compare the outcome in in vitro fertilisation (IVF) children (after fresh embryo transfer) from multiple and singleton births with one another, and with normally conceived control children. METHODS: A cohort of 278 children (150 singletons, 100 twins, 24 triplets and four quadruplets), conceived by IVF after three fresh embryos had been transferred, born between October 1984 and December 1991, and 278 normally conceived control children (all singletons), were followed up for four years after birth. They were assessed for neonatal conditions, minor congenital anomalies, major congenital malformations, cerebral palsy and other disabilities. Control children, all born at term, were matched for age, sex and social class. RESULTS: The ratio of male:female births was 1.03. Forty six per cent of IVF children were from multiple births; 34.9% were from preterm deliveries; and 43.2% weighed less than 2500 g at birth. The IVF singletons were on average born one week earlier than the controls, weighed 400 g less, and had a threefold greater chance of being born by caesarean section. The higher percentage of preterm deliveries was largely due to multiple births and they contributed to neonatal conditions in 45.0% of all IVF children. The types of congenital abnormalities varied: 3.6% of IVF children and 2.5% of controls had minor congenital anomalies, and 2.5% of IVF children and none of the controls had major congenital malformations. The numbers of each specific type of congenital abnormality were small and were not significantly related to multiple births. IVF children (2.1%) and 0.4% of the controls had mild/moderate disabilities. They were all from multiple births, including two children with cerebral palsy who were triplets. CONCLUSIONS: The outcome of IVF treatment leading to multiple births is less satisfactory than that in singletons because of neonatal conditions associated with preterm delivery and disabilities in later childhood. A reduction of multiple pregnancies by limiting the transfer of embryos to two instead of three remains a high priority.
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Transferencia de Embrión , Fertilización In Vitro , Resultado del Embarazo , Parálisis Cerebral , Cesárea , Estudios de Cohortes , Anomalías Congénitas , Femenino , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Recien Nacido Prematuro , Masculino , Embarazo , Estudios Prospectivos , Razón de Masculinidad , Trillizos , GemelosRESUMEN
To test in vivo the effect of previously observed inhibition of collagen type I transcription by the plant alkaloid Halofuginone, deep flexor tendons of 12 chickens were severed and sutured, and Halofuginone was applied topically at the site of surgery. Intact tendons, and severed but untreated tendons served as controls. The effect of the treatment was assessed by histological, biochemical, and biomechanical examinations of the operated and intact tendons three weeks after surgery. The results indicated an almost complete absence of fibrous peritendinous adhesions in the histologic sections of the Halofuginone treated tendons. There was a statistically significant decrease in collagen contents of and in both force and energy required to pull out the Halofuginone treated tendons from their sheath, relative to the untreated controls. Halofuginone had no effect on the cellularity of the healing tissue. We conclude that Halofuginone is a potent inhibitor of fibrous peritendinous adhesions with potentially important clinical applications.
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Colágeno/metabolismo , Inhibidores de la Síntesis de la Proteína/uso terapéutico , Quinazolinas/uso terapéutico , Traumatismos de los Tendones/tratamiento farmacológico , Adherencias Tisulares/prevención & control , Animales , Pollos , Regulación de la Expresión Génica , Hidroxiprolina/metabolismo , Inflamación/tratamiento farmacológico , Piperidinas , Quinazolinonas , Estadísticas no Paramétricas , Traumatismos de los Tendones/patología , Traumatismos de los Tendones/cirugía , Adherencias Tisulares/patologíaRESUMEN
A novel monoclonal antibody (BAT) to the B-lymphoblastoid cell line activates murine lymphocytes and exhibits a striking antitumor activity in mice. In order to evaluate the potential use of this antibody against human cancer, we have investigated its immuno-stimulatory properties on human peripheral blood lymphocytes (PBL). Our findings demonstrate that BAT mAb induces proliferation and cytotoxicity in human PBL against natural-killer-cell-sensitive and natural-killer-cell-resistant tumor cell lines. Interleukin-2 at a low concentration synergizes with BAT mAb in eliciting these effects. BAT mAb binds to human peripheral T cells as revealed by a double-labelling technique using anti-CD3 and BAT mAb. The molecular mass of the antigen recognized by BAT mAb was 48-50 kDa under reducing and non-reducing conditions. This study provides a basis for future experiments to evaluate the use of BAT mAb in the immunotherapy of cancer.
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Anticuerpos Monoclonales/metabolismo , Anticuerpos Monoclonales/farmacología , Antígenos de Neoplasias/inmunología , Antígenos de Neoplasias/metabolismo , Linfocitos B/inmunología , Inmunoterapia , Activación de Linfocitos/efectos de los fármacos , Activación de Linfocitos/inmunología , Neoplasias Experimentales/inmunología , Neoplasias Experimentales/terapia , Adyuvantes Inmunológicos/metabolismo , Adyuvantes Inmunológicos/farmacología , Animales , Anticuerpos Monoclonales/uso terapéutico , Citotoxicidad Inmunológica , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/inmunología , Ratones , Ratones Endogámicos BALB C , Peso Molecular , Neoplasias Experimentales/sangre , Unión Proteica , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Linfocitos T/metabolismo , Timidina/metabolismo , Distribución Tisular , TritioRESUMEN
Seventeen of 55 children and adolescents with Gaucher's disease presented with upper limb pain. Seven had nonspecific pain, 11 had bone crisis, and 2 had arthritis symptoms in the proximal interphalangeal joints. X-ray films of both hands showed osteopenia and thinning of the cortex in half of the patients.
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Brazo/diagnóstico por imagen , Enfermedades Óseas/etiología , Enfermedad de Gaucher/complicaciones , Mano/diagnóstico por imagen , Adolescente , Adulto , Enfermedades Óseas/diagnóstico por imagen , Niño , Femenino , Humanos , Masculino , RadiografíaRESUMEN
The long term neurodevelopmental outcome was assessed in 23 survivors born with congenital diaphragmatic hernia who had been managed by an elective delay in surgical repair after a period of stabilisation. This cohort was treated in one neonatal surgical unit between 1983 and 1989 by a single team of surgeons and anaesthetists. All children underwent comprehensive neurological, developmental, and anthropometric assessment at a mean age of 56 (range 18-94) months. Two children (9%) had major disability (one with hemiplegia and one with a lower limb monoplegia) and two further children had minor disabilities (one had partial sightedness and squint, the other squint only). The mean developmental quotient (DQ) for the group was 108 (SD 10.8) and none had developmental delay (defined as DQ < 70). Infants who had spent more time in hospital, or had had a longer duration of ventilation, tended to have lower weights and lower occipitofrontal circumference centiles in later childhood. Preoperative stabilisation and delayed surgery for congenital diaphragmatic hernia is not associated with an impaired neurodevelopmental outcome.
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Discapacidades del Desarrollo/etiología , Hernia Diafragmática/cirugía , Niño , Preescolar , Hernias Diafragmáticas Congénitas , Humanos , Lactante , Discapacidad Intelectual/etiología , Tiempo de Internación , Pronóstico , Estudios Retrospectivos , Factores de TiempoRESUMEN
In order to evaluate the risk of acute cholecystitis in diabetic patients, we analyzed 2,700 consecutive cholecystectomies, 566 of which were performed in the presence of acute cholecystitis. Of these patients 123 had diabetes mellitus (DM) and 433 had no diabetes (ND). The aim of this study was to establish the comparative risks in the two groups. We found that diabetics are more likely to be operated on in the acute stage of their disease (22% vs. 12%). The DM group had a higher rate of septic bile, gangrenous changes and perforations of the gallbladder wall. The morbidity rate was higher in the DM group (21% vs. 9%), and mortality was slightly higher in the DM group. The degree of additional operative risk does not in our view justify recommending cholecystectomy in diabetic patients with asymptomatic gallstones. Early surgery however, is highly recommended in diabetics with symptomatic gallstones and acute cholecystitis.
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Colecistectomía , Colecistitis/cirugía , Complicaciones de la Diabetes , Enfermedad Aguda , Anciano , Colecistectomía/efectos adversos , Colecistectomía/mortalidad , Colecistitis/complicaciones , Femenino , Humanos , Masculino , RiesgoRESUMEN
The timing of cholecystectomy in acute cholecystitis is still controversial. A marked change toward early surgery has been noted in the past decade. In a retrospective study of 197 patients we evaluated the results of cholecystectomy in 117 who underwent elective cholecystectomy, and in 80 operated on during the acute phase of cholecystitis. The diagnosis of acute cholecystitis was by isotope scan (HIDA) or ultrasound. There was no case of misdiagnosis. 3 patients died postoperatively: 2 in the early operation group (1 had emergency cholecystectomy) and 1 in the elective group. Postoperative complications were more frequent in the early surgery group (p = 0.06). The highest morbidity was in early cholecystectomy in those older than 60 years who had cardiovascular disease (p less than 0.0002). Hernia in the scar was a unique complication of the early operation. According to most studies reviewed, early operation eliminates the need for emergency operation when conservative treatment fails, without increasing morbidity or mortality. Therefore, early operation during the acute phase of cholecystectomy is advised. For patients older than 60 years who have cardiovascular disease, we recommend delaying surgery until the acute inflammation subsides. The waiting period before surgery should be as short as possible in order to reduce the risk of recurrent cholecystitis and its complications.
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Colecistectomía , Colecistitis/cirugía , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Colecistitis/diagnóstico , Urgencias Médicas , Humanos , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , Factores de TiempoRESUMEN
Hemosuccus pancreaticus is a rare condition where bleeding occurs through the pancreatic duct, usually due to a pseudoaneurysm of the splenic artery. We describe a patient with spontaneous rupture of the splenic artery that caused hemosuccus pancreaticus and later massive hemoperitoneum. The pathological process had lasted at least 10 days before the diagnosis was established. The patient underwent an emergency operation during which splenectomy and distal pancreatectomy were successfully performed.
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Hemoperitoneo/etiología , Hemorragia/etiología , Enfermedades Pancreáticas/etiología , Arteria Esplénica , Humanos , Masculino , Persona de Mediana Edad , Rotura Espontánea , Enfermedades Vasculares/complicaciones , Enfermedades Vasculares/diagnósticoRESUMEN
The problem of long waiting list of patients for varicose vein surgery may be eased by bilateral operation when both limbs are involved and not in two separate operations as is the practice in many surgical centers. We found that patients undergoing unilateral high ligation and stripping did not differ from patients who had bilateral limb operation in terms of complications, morbidity and length of hospitalization. Most of our patients were released after one day of hospitalization. Therefore, we recommend bilateral operation when there is an indication, rather than two unilateral operations.
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Vena Safena/cirugía , Várices/cirugía , Femenino , Estudios de Seguimiento , Humanos , Tiempo de Internación , Ligadura , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Insuficiencia Venosa/cirugíaRESUMEN
In 232 newborn babies of less than 32 weeks' gestational age ultrasound brain scans were carried out shortly after birth, daily for the first week of life, and at least twice weekly thereafter. Periventricular echogenicity associated with or progressing to periventricular leukomalacia (ischaemic brain lesions) was present in nine babies within two hours of birth (early onset); 30 other babies subsequently developed similar lesions (late onset). Babies with early onset lesions were more likely to have a history of intrauterine growth retardation and to have recurrent apnoea in the first few hours after birth. By contrast, late onset lesions were associated with hyaline membrane disease. In later childhood four of six survivors with early onset periventricular leukomalacia, and seven of 14 survivors with late onset periventricular leukomalacia, had various disabilities including spastic diplegia, impaired vision, squints, sensorineural hearing loss, and developmental delay. In a third of the children with disabilities ischaemic brain lesions were noted within two hours of birth, raising the possibility that some of this damage had taken place before or during birth.
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Isquemia Encefálica/diagnóstico , Encéfalo/patología , Enfermedades del Prematuro/diagnóstico , Isquemia Encefálica/complicaciones , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/patología , Preescolar , Discapacidades del Desarrollo/etiología , Femenino , Retardo del Crecimiento Fetal/complicaciones , Humanos , Enfermedad de la Membrana Hialina/complicaciones , Recién Nacido , Enfermedades del Prematuro/diagnóstico por imagen , Enfermedades del Prematuro/patología , Leucomalacia Periventricular/complicaciones , Leucomalacia Periventricular/diagnóstico , Leucomalacia Periventricular/diagnóstico por imagen , Leucomalacia Periventricular/patología , Complicaciones del Trabajo de Parto , Embarazo , UltrasonografíaRESUMEN
Six infants with congenital myotonic dystrophy survived after neonatal intensive care. In later childhood they were assessed by the Griffiths Mental Development Scales: five children were functioning in the mildly handicapped to borderline range of development (DQ 64.0 to 79.0) and the remaining child was severely delayed in development (DQ 33.0). The five children with higher DQ values had a history of ventilatory support of 30 days or less after birth. By contrast, the remaining child with the lowest DQ value had been ventilated for 43 days. This study provides further evidence that prolonged ventilation after birth has prognostic significance in identifying severely affected cases with congenital myotonic dystrophy.
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Discapacidades del Desarrollo/etiología , Distrofia Miotónica/congénito , Preescolar , Humanos , Lactante , Respiración Artificial/efectos adversosRESUMEN
This paper deals specifically with the complex psychological sequelae and management of severe burns in children and adolescents. The impact on the families of these patients must not be ignored. Early psychological intervention may prevent later psychological problems.
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Conducta del Adolescente , Quemaduras/psicología , Conducta Infantil , Adaptación Psicológica , Adolescente , Adulto , Quemaduras/rehabilitación , Quemaduras/terapia , Selección de Profesión , Niño , Femenino , Humanos , Relaciones Interpersonales , Masculino , Padres/psicología , Apoyo SocialRESUMEN
This study has shown that a multidisciplinary group approach to counselling parents of burned children will decrease parental anxiety, and that medical, psychological and social problems will feature primarily in group discussions.
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Quemaduras/psicología , Consejo/métodos , Padres/psicología , Adulto , Niño , Femenino , Humanos , MasculinoRESUMEN
An analysis of the problems that are referred by general practitioners to a clinical child psychologist working in the community is presented. To illustrate some of the principles of assessment and management an example from each of three main categories--behaviour problems, emotional disturbances, and disorders of function--is given.