RESUMEN
Organochlorine (OC) pesticide concentrations in blood plasma samples from 88 juvenile white sturgeon collected from the lower Columbia River were measured and compared to plasma sex steroid and OC tissue levels previously measured in corresponding fish. Significant squared correlation coefficients between summation operator DDT concentrations in sturgeon plasma and gonads and livers were 0.37 and 0.32, respectively. Significant negative correlations between plasma testosterone concentration and plasma Sigma DDT concentration in male fish (r(2)=0.26), plasma 17beta estradiol concentration and plasma Sigma DDT concentration in female fish (r(2)=0.38) and condition factor and plasma Sigma DDT concentration in all fish were found (r(2)=0.17). These results suggest that blood plasma may be a suitable nondestructive method for monitoring adult sturgeon population for persistent OC contaminants.
Asunto(s)
Monitoreo del Ambiente/métodos , Peces/sangre , Hidrocarburos Clorados/sangre , Plaguicidas/sangre , Ríos/química , Contaminantes Químicos del Agua/sangre , Animales , Femenino , Hormonas Esteroides Gonadales/sangre , Masculino , OregonAsunto(s)
Asiático , Negro o Afroamericano , Conducta Alimentaria/etnología , Hispánicos o Latinos , Población Blanca , Adolescente , Adulto , Población Negra , Niño , Productos Lácteos , Femenino , Frutas , Humanos , Intolerancia a la Lactosa , Masculino , Massachusetts , Encuestas Nutricionales , Encuestas y Cuestionarios , Verduras , Vietnam/etnologíaRESUMEN
We describe and validate a new minimally invasive method for continuous measurement of tracheal diameter in anesthetized dogs. The method is based on measuring displacement of water into and out of a modified endotracheal tube cuff placed in the trachea. The system was calibrated to allow tracheal diameter to be calculated from known cuff volume. The resolution of the method in measuring changes in tracheal diameter is 0.1 mm over a range of approximately 10-25 mm. The apparatus was tested in five dogs by observing the response of the trachea to four stimuli previously shown to alter tracheal tone: stimulation of nasal mucosa, hyperinflation of the lungs, induction of hypocapnea, and infusion of atropine. The observed changes in tracheal diameter were generally consistent with those of previous studies. The direction and extent of changes in tracheal diameter in response to the test conditions were confirmed by fluoroscopy. We conclude that continuous measurement of volume changes in the cuff reflects corresponding changes in tracheal diameter.
