Postradiation pleomorphic malignant fibrous histiocytoma of the breast

A case of primary malignant fibrous histiocytoma (MFH) of the breast occurring two years after surgical excision and radiation therapy for a carcinoma of the left breast is reported. Fine needle aspiration was positive for malignant cells, consistent with a pleomorphic sarcoma. Cytologic examination revealed giant cells with marked pleomorphism. Some cells showed single large nuclei with cytoplasmic vacuoles while others revealed multinucleation with foamy cytoplasm, phagocytosed erythrocytes and cellular debris. These findings are considered useful in the cytologic diagnosis of the pleomorphic variant of MFH.     

Correlation of isonicotinic acid hydrazide infiltration across the blood-brain barrier to postnatal development in rats.

Changes in the isonicotinic acid hydrazide (INH) concentration in rat blood and brain were studied in correlation to postnatal development in groups of animals aged 21 and 42 days and 3 months. In the first part of the experiments, INH was administered intravenously to all the age groups in a dose of 100 mg/kg. In the second part, the dose was related to extracellular fluid volume, so that the 3-week-old rats were given 154 mg/kg, the 6-week-old animals 129 mg/kg and the 3-month-old animals 100 mg/kg. After a dose of 100 mg/kg, INH levels in the blood of 21-day-old rats were significantly lower than in 42-day-old and adult animals. The brain INH levels did not differ significantly. On relating the dose to the amount of extracellular fluid, there were no significant differences in the blood INH levels, but the levels in the brain of 21- and 42-day-old rats were significantly higher than in 3-month-old animals. Blood volume related to body weight and brain weight did not differ in the various age groups. The authors conclude that the blood-brain barrier for isonicotinic acid hydrazide alters in rats during postnatal development. In young animals (21- and 42-day-old), more INH infiltrates into the CNS than in adult animals.     

Effects of inhaled nicotine on instrumental learning of blood pressure responses.

The present study investigated the effects of biofeedback of arterial blood pressure on cortical, peripheral, and psychological measures and the dependence of these effects on nicotine. Four groups of subjects, nonsmokers, and habitual smokers who smoked cigarettes during the experimental sessions containing 0.3, 0.8, or 1.5 mg nicotine, respectively, participated in a feedback paradigm in which continuous feedback of mean blood pressure was provided for intervals of 8 s each. While tonic blood pressure did not differ between the groups, the ability to modulate blood pressure (under feedback conditions) was restricted in smokers as compared to nonsmoking subjects; increasing nicotine dosage was accompanied by poorer performance. Independently of habitual smoking and nicotine doses, heart rate increased during feedback and under conditions of blood pressure increase. In smokers, activity in the alpha band was reduced in a dose-dependent manner. Slow cortical potentials (SCPs) during the feedback interval varied with self-induced blood pressure changes in nonsmokers (blood pressure increase was accompanied by reduced surface-negative potential shifts and vice versa), while SCP variations during feedback conditions were small in smokers, more so under the influence of 0.3 and 0.8-mg nicotine, less so under 1.5 mg. Verbal reports suggest that awareness of performance strategies may not be a necessary variable for performance on the blood pressure regulation task.