RESUMEN
The measurement of hepatic iron overload is of particular interest in cases of hereditary hemochromatosis or in patients subject to periodic blood transfusion. The measurement of plasma ferritin provides an indirect estimate but the usefulness of this method is limited by many common clinical conditions (inflammation, infection, etc). Liver biopsy provides the most quantitative direct measurement of iron content in the liver but the risk of the procedure limits its acceptability. This work studies the feasibility of a magnetic induction (MI) low-cost system to measure liver iron overload. The excitation magnetic field (B0, frequency: 28 kHz) was produced by a coil, the perturbation produced by the object (deltaB) was detected using a planar gradiometer. We measured ten patients and seven volunteers in supine and prone positions. Each subject was moved in a plane parallel to the gradiometer several times to estimate measurement repeatability. The real and imaginary parts of deltaB/B0 were measured. Plastic tanks filled with water, saline and ferric solutions were measured for calibration purposes. We used a finite element model to evaluate the experimental results. To estimate the iron content we used the ratio between the maximum values for real and imaginary parts of deltaB/B0 and the area formed by the Nyquist plot divided by the maximum imaginary part. Measurements in humans showed that the contribution of the permittivity is stronger than the contribution of the permeability produced by iron stores in the liver. Defined iron estimators show a limited correlation with expected iron content in patients (R < or = 0.56). A more precise control of geometry and position of the subjects and measurements at multiple frequencies would improve the method.
Asunto(s)
Hemocromatosis/diagnóstico , Hígado , Magnetismo/instrumentación , Simulación por Computador , Humanos , Modelos Teóricos , Proyectos PilotoRESUMEN
The purpose of the present study was to determine if the administration of a biosynthetic human growth hormone (bGH) was able to enhance the efficacy of total parenteral nutrition (PN). Patients (n = 38) who had undergone major gastrointestinal surgery were randomly divided in two groups. Group I (n = 20) treated only with PN and Group II (n = 18) treated as in Group I plus bGH (4 UI/daily). Our study shows that the administration of bGH produces a significant increase in serum levels of growth hormone and Somatomedin-C. It also caused a positive nitrogen balance from the first 24 hours on (p less than 0.01). In Group II on day 12 after operation a statistically significant increase in transferrin (p less than 0.05), albumin (p less than 0.01) and total proteins (p less than 0.02) was observed. Our study suggest that the administration of bGH produces, perhaps through Somatomedin-C as mediator, an increase in protein synthesis.
Asunto(s)
Enfermedades Gastrointestinales/metabolismo , Hormona del Crecimiento/farmacología , Nutrición Parenteral Total , Cuidados Posoperatorios/métodos , Adulto , Anciano , Femenino , Enfermedades Gastrointestinales/cirugía , Humanos , Masculino , Persona de Mediana EdadRESUMEN
In the present retrospective study we examine the complications arising from simple goiter operations based on the analysis of 2,035 cases. The mortality rate is extremely low (0.3%). The most typical intraoperative complications - such as unilateral vocal cord paralysis (1.6%) and permanent parathyroprival hypocalcemia (0.4%) were observed to occur much more frequently in cases of subtotal thyroidectomy than in those of partial resection. - As a result of the introduction of synthetic reabsorbent sewing materials, healing problems have been drastically reduced (0.4%). Hypothyreosis and goiter recurrence can be avoided in cases of subtotal thyroidectomy by life-long and individually adjusted administration of thyroid hormones (rate of incidence in our study 3.1%). - In our view a subtotal thyroidectomy is indicate in cases where malignity is suspected (one or more cold nodules).