RESUMEN
Gentamicin (4%) was injected intratympanically into the middle ear of guinea pigs and the effects on the brainstem evaluated 28 days later by immunohistochemistry with an antibody against glial fibrillary acidic protein to detect astrocytes, and by cytochrome oxidase staining to detect metabolic activity. Astrocytes were observed in the cochlear nucleus indicating the possible presence of anterograde degeneration. Deficiencies in the intensity of cytochrome oxidase staining up to the level of the superior olivary complex indicated the presence of abnormal metabolic activity. Both of these observations support the conclusion that a single intratympanic injection of gentamicin may lead to neuronal degeneration along the central auditory pathway.
Asunto(s)
Vías Auditivas/efectos de los fármacos , Tronco Encefálico/efectos de los fármacos , Gentamicinas/toxicidad , Degeneración Nerviosa/fisiopatología , Animales , Astrocitos/química , Tronco Encefálico/patología , Oído Medio/efectos de los fármacos , Proteína Ácida Fibrilar de la Glía/análisis , Cobayas , Inmunohistoquímica , Inyecciones , MasculinoRESUMEN
Clinical and morphologic observations are described in four patients who had severe aortic regurgitation from severe systemic hypertension unassociated with aortic dissection; each patient underwent aortic valve replacement. Although aortic regurgitation of minimal or mild degree is well recognized to occur in patients with systemic hypertension, severe degrees of aortic regurgitation are rare in such patients; aortic valve replacement in such patients has not previously been reported. Why these four patient had such severe aortic regurgitation was not determined. Although systemic hypertension is rarely a cause, it nevertheless must be added to the list of causes of severe pure aortic regurgitation.
Asunto(s)
Insuficiencia de la Válvula Aórtica/cirugía , Válvula Aórtica/cirugía , Prótesis Valvulares Cardíacas , Hipertensión/complicaciones , Adulto , Anciano , Válvula Aórtica/diagnóstico por imagen , Insuficiencia de la Válvula Aórtica/diagnóstico por imagen , Insuficiencia de la Válvula Aórtica/etiología , Diástole , Ecocardiografía , Femenino , Insuficiencia Cardíaca/etiología , Insuficiencia Cardíaca/patología , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/patología , Humanos , Masculino , Persona de Mediana Edad , Válvula Mitral/patología , Pulso Arterial , Radiografía , SístoleRESUMEN
A patient is described with clinical features of massive pulmonary embolism and a normal pulmonary angiogram. At necropsy, a large thrombus obstructed right ventricular outflow. A right atrial or right ventricular angiogram is suggested in patients suspected of having pulmonary embolism when a pulmonary angiogram shows the pulmonary trunk and main right and left pulmonary arteries to be normal.