RESUMEN
BACKGROUND: : To expand minimally invasive beating-heart surgery, we have developed a miniature 2-footed crawling robot (HeartLander) that navigates on the epicardium. This paradigm obviates mechanical stabilization and lung deflation, and avoids the access limitations of current approaches. We tested the locomotion of the device on a beating porcine heart accessed through a closed-chest subxiphoid approach. METHODS: : HeartLander consists of 2 modules that are connected by an extensible midsection. It adheres to the epicardium using suction pads. Locomotion and turning are accomplished by moving the 2 modules in an alternating fashion using wires that run through the midsection between them. After a preliminary test with a plastic beating-heart model, we performed a porcine study in vivo. The device was inserted into the pericardial space through a subxiphoid incision, while the test was observed using a left thoracoscopy. The blood pressure and electrocardiogram were monitored, and vacuum pressure and driving forces on the wires were recorded. RESULTS: : HeartLander traveled across the anterior and lateral surfaces of the beating heart without restriction, including locomotion forward, backward, and turning. The vacuum pressure was kept below 450 mm Hg at all times. The average maximum force during elongation was 1.86 ± 0.97 N, and during retraction was 1.24 ± 0.33 N. No adverse hemodynamic or electrophysiologic events were noted during the trial. No epicardial damage was found on the excised heart after the porcine trial. CONCLUSIONS: : The current HeartLander prototype demonstrated safe and successful locomotion on a beating porcine heart through a closed-chest subxiphoid approach.
RESUMEN
A total of 211 selected paediatricians were invited to participate in a national survey designed to evaluate the age of attainment of developmental milestones in children aged 0-5 years. Following a pilot study and a cascade training design, 61.1% of the paediatricians successfully completed the data collection on 139 developmental items. In the pilot study, there were more missing (not performed) items in children over one year of age, thus confirming the impression that paediatricians are more familiar with evaluating development in infants. However, in the age range 1-5 years, there were significantly fewer missing items in the gross motor area than in the other areas. Following a training programme and data editing and cleaning, a final sample of 3573 healthy, normal children was obtained. The impact of the training process was significant, in the sense that 3.5% of the items in children older than one year were not performed by the paediatricians before training, but this percentage was reduced to 1.9% after training (P < 0.01). The sample formed 0.11% of the national population less than 6 years of age and included a sex ratio of 1.01 compared with a national ratio of 1.02. There were no significant differences in the geographical distribution of the sample in comparison with that of the national population. The social composition, assessed by maternal education level, was biased towards a better education level than the national population. Mean Z-scores for height and weight were not significantly different from zero, when calculated on the basis of the national growth standards. In addition to successfully obtaining a representative sample for the analysis of the age of attainment of developmental milestones in Argentinian children, the survey also accomplished an educational objective in the training of paediatricians in developmental paediatrics.
Asunto(s)
Desarrollo Infantil , Bases de Datos Factuales/normas , Encuestas Epidemiológicas , Pediatría , Proyectos de Investigación/normas , Argentina , Preescolar , Estudios Transversales , Femenino , Humanos , Lactante , Recién Nacido , Estudios Longitudinales , Masculino , Proyectos Piloto , Evaluación de Programas y Proyectos de Salud , Valores de Referencia , Reproducibilidad de los Resultados , MuestreoRESUMEN
PIP: Sub-Saharan Africa (SSA) has the greatest population growth rates, the highest levels of infant and child mortality, and the poorest economies in the world. The physical quality of life index for developed countries is 80, yet for 33 SSA countries it ranges from 20.5-66. Routine monitoring of growth and nutritional status of children demonstrates their health status. The proportion of low birth weight infants is high in SSA with most countries having levels 10-20% . Further even though average birth weight consistently rose during the 1980s in SSA, the range of smallest to largest mean birth weights is lower than the medians for developed counties. Moreover 40% of 5 year olds are mild or moderately malnourished as evidenced by growth retardation and some biochemical changes, yet they exhibit or clinical signs and symptoms. Besides diarrhea often exacerbates malnutrition. Through childhood and adolescence, growth patterns (particularly among the rural Turkana pastoralists) steadily deviate from the 50th centile of US norms. Thus almost 50% of early adolescents in rural areas are below the 5th centile. Studies have found that pastoralist children tend to begin being slightly above the 5th centile of US norms and gradually fall below it. Further peak growth velocities among SSA children are low, but postpeak velocities are higher than equal velocities for children in developed countries. Thus adult heights are only between the 5th-50th centiles. Throughout childhood and adolescence, US Blacks have higher absolute levels of subcutaneous fat than children in SSA. Yet the main centralized patterning of fat in SSA children basically equals that of US Blacks, but invariably less marginal than in Whites. In conclusion, adverse socioeconomic conditions in SSA result in low levels of health at all growth phases thereby confounding their genetic potential.^ieng
Asunto(s)
Adolescente , Adulto , Negro o Afroamericano , Estatura , Peso Corporal , Fenómenos Fisiológicos Nutricionales Infantiles , Protección a la Infancia , Niño , Comparación Transcultural , Diarrea , Suplementos Dietéticos , Crecimiento , Recién Nacido de Bajo Peso , Lactante , Mortalidad , Fenómenos Fisiológicos de la Nutrición , Clase Social , Migrantes , Población Blanca , África , África del Sur del Sahara , África Austral , Factores de Edad , Américas , Biología , Peso al Nacer , Población Negra , América Central , Desarrollo Infantil , Cultura , Atención a la Salud , Demografía , Países Desarrollados , Países en Desarrollo , Enfermedad , Economía , Emigración e Inmigración , Etnicidad , Guatemala , Salud , Planificación en Salud , Servicios de Salud , América Latina , América del Norte , Fisiología , Población , Características de la Población , Dinámica Poblacional , Atención Primaria de Salud , Investigación , Factores Socioeconómicos , Sudáfrica , Estados UnidosRESUMEN
One hundred sixteen patients who had had kwashiorkor between the ages of 5 months and 4 4/12 years and 89 controls were the subjects of a 15-year follow-up study of their growth and development. We report the findings of a longitudinal analysis of 53 (30 females) of the ex-patients and 30 (15 females) of the controls, selected because at the end of 15 years of study they conformed to the criteria of adult secondary sexual characteristics, height velocity less than 2 cm/yr, and completeness of data. Nonlinear curve-fitting techniques were applied to the height and weight data for these subjects using the Preece-Baines model 1 growth function to determine the timing and magnitude of adolescent growth spurts and the associated biologic changes. Both ex-patients and controls grew below the 25th percentile of British longitudinal standards, but the male ex-patients were heavier, and perhaps taller, than the controls for most of their childhood and adolescence. Velocity curves indicated that the ex-patients had higher pre-adolescent peak increments than the controls and a generally longer growth spurt of reduced magnitude. Two possible explanations are discussed: Garrow and Pike's theory that children with kwashiorkor have a genetic potential for greater physical growth, and a socioeconomic crisis occurring within a family affects the youngest child, who subsequently requires a longer time to recover than do siblings within an improving socioeconomic situation.