The RNA/DNA and protein/DNA ratios were evaluated to determine the physiological condition of the smooth dogfish shark (Mustelus canis) in its natural habitat. The samples were collected from animals captured by the Venezuelan trawling fleet operating between the north coast of Sucre State and Margarita Island. Proteins (Bradford method) and nucleic acids (fluorometric method) were quantified from muscle tissue samples. Instantaneous growth was estimated from the RNA/DNA and protein/DNA relationships. A decrease in the RNA/DNA ratio was observed in relation to body length in both sexes. In the case of the protein/DNA ratio, the distribution values do not show any tendency relative to body length or sex. The results show that the RNA/DNA ratio can be used to analyze the instantaneous growth and population health of sharks.

Se realizó una evaluación preliminar de los índices ARN/ADN y proteína/ADN para determinar la condición fisiológica de juveniles del tiburón viuda virma Mustelus canis en su hábitat natural. Las muestras fueron obtenidas de una embarcación de la flota de arrastre venezolana que realizó sus operaciones en la región nororiental de Venezuela, entre la costa norte del estado Sucre y la Isla de Margarita. Las proteínas y ácidos nucleicos fueron cuantificadas en tejido muscular mediante el método de Bradford y el método fluorimétrico, respectivamente. El crecimiento instantáneo se estimó mediante las relaciones ARN/ADN y proteína/ADN. Se encontró una tendencia en la disminución del índice ARN/ADN con respecto a la talla en ambos sexos. Con relación al índice proteína/ADN, no se observó en la distribución de los valores un patrón o comportamiento definido según la talla y sexo. Los resultados muestran que el índice de ARN/ADN puede ser utilizado para evaluar el crecimiento instantáneo y la salud de las poblaciones de tiburones.

Rounded atelectasis (RA) is a benign and unusual form of subpleural lung collapse that has been described mostly in asbestos-exposed workers. This form of atelectasis manifests as a lung nodule and can be confused with bronchogenic carcinoma upon conventional radiologic examination. The objective of the present study was to evaluate the variation in contrast uptake in computed tomography for the identification of asbestos-related RA in Brazil. Between January 1998 and December 2000, high-resolution computed tomography (HRCT) was performed in 1658 asbestos-exposed workers. The diagnosis was made in nine patients based on a history of prior asbestos exposure, the presence of characteristic (HRCT) findings and lesions unchanged in size over 2 years or more. In three of them the diagnosis was confirmed during surgery. The dynamic contrast enhancement study was modified to evaluate nodules and pulmonary masses. All nine patients with RA received iodide contrast according to weight. The average enhancement after iodide contrast was infused, reported as Hounsfield units (HU), increased from 62.5 ± 9.7 to 125.4 ± 20.7 (P < 0.05), with a mean enhancement of 62.5 ± 19.7 (range 40 to 89) and with a uniform dense opacification. In conclusion, in this study all patients with RA showed contrast enhancement with uniform dense opacification. The main clinical implication of this finding is that this procedure does not permit differentiation between RA and malignant pulmonary neoplasm.

The Horne-Östberg questionnaire partly covers some factors that may be important determinants of peak time and characterize patterns of behavior. We conducted a study for the evaluation of self-reported behavioral states (hunger sensation, availability for study, physical exercise, solving daily problems, and time preferences) as expressions of underlying cyclic activity. Three hundred and eighteen community subjects without history of medical, psychiatric, or sleep disorders were evaluated in a cross-sectional design. A self-report about daily highest level of activity was used to categorize individuals into morning, evening, and indifferently active. Time-related behavioral states were evaluated with 23 visual analog questions. The responses to most analogic questions were significantly different between morning and evening active subjects. Logistic regression analysis identified a group of behaviors more strongly associated with the self-reported activity pattern (common wake up time, highest subjective fatigue, as well as wake up, bedtime, exercise and study preferences). These findings suggested that the patterns of activity presented by normal adults were related to specific common behavioral characteristics that may contribute to peak time.