Intratympanic injection of sodium arsanilate (atoxyl) solution results in postural changes consistent with changes described for labyrinthectomized rats.

Intratympanic injections of sodium arsanilate (atoxyl) have been shown to produce vestibular dysfunction in the rat. Unilateral and bilateral dysfunction can be distinguished by changes in the animals' postures. These changes are consistent with changes described for unilateral or bilateral labyrinthectomized rats. The intratympanic injection technique offers a simple yet effective alternative to labyrinthectomy.

Behavioral and physiological effects of chronic 2,450-MHz microwave irradiation of the rat at 0.5 mW/cm2.

Adult male Long-Evans rats were intermittently exposed to 2450 MHz CW microwaves at an average power density of 0.5 mW/cm2 for 90 days. The resulting SAR was 0.14 W/kg (range 0.11 to 0.18 W/kg). The animals were exposed 7 h/day, 7 days/wk, for a total of 630 h in a monopole-above-ground radiation chamber while housed in Plexiglas holding cages. Daily measures of body mass and food and water intake indicated no statistically significant effects of microwave exposure. Monthly assessment of reactivity to electric footshock, levels of cholinesterase and sulfhydryl groups in blood, and 17-ketosteroids in urine revealed no reliable differences between 14 sham-exposed and 14 microwave-exposed rats. After the 90 days of exposure, seven rats, randomly chosen from each group, were assessed for open-field behavior, shuttlebox performance, and schedule-controlled (IRT schedule) lever pressing for food pellets. Statistically significant differences between microwave-exposed and sham-exposed rats were observed in shuttlebox performances and lever pressing. Post mortem measures of mass of several organs and microscopic examination of adrenal tissue revealed no differences between the two groups of animals.

Persistent transitional circulation. Roentgenographic findings in thirteen infants.

Chest roentgenograms in 13 infants and angiocardiograms in 11 infants with persistent transitional circulation (PCT) syndrome were reviewed. Chest radiographs typically revealed congestive heart failure with pulmonary venous congestion, cardiomegaly, hepatomegaly, and pleural effusions. Angiocardiography demonstrated a right-to-left shunt through the ductus arteriosus, ventricular dilatation, poor myocardial function, and ventricular emptying. Cardiopulmonary abnormalities resolved over a period of 2-6 days in survivors. PTC syndrome as seen at the authors' institution has been an important and relatively common cause of congestive heart failure and cyanosis in the newborn. The incidence of congestive failure was higher than in other reported series.