Sternal metastases and associated pathological fractures

A review of 839 necropsies revealed 415 cases of malignant neoplasm, 63 of which were found to have evidence of metastatic spread to the sternum. Nineteen of these metastases resulted in pathological sternal fractures. Fine detail radiography proved a quick and accurate technique for detecting these lesions post mortem. The characteristics of pathological sternal fractures were compared with traumatic sternal fractures with respect to deformity and healing. Pathological fractures of the sternum demonstrate a tendency to greater deformity and slower healing than traumatic sternal fractures.     

Testosterone affects food intake and body weight of weanling male rats

The effects of testosterone propionate (TP) on food intake and body weight were investigated using castrated prepubertal male rats. Regardless of dose (1 mg, 0.2 mg or 0.1 mg), daily injections of TP increased body weight gain and food intake during the prepubertal period (from 22 to 40 days to age). Considering previous results, the present observations suggest that in the male rat sensitivity to the effects of gonadal hormones on feeding develops earlier than in females.     

Two T cell epitopes from the M5 protein of viable Streptococcus pyogenes engage different pathways of bacterial antigen processing in mouse macrophages

We studied the mechanisms of MHC class II-restricted bacterial Ag processing of the surface fibrillar M5 protein from viable Streptococcus pyogenes in murine macrophages. Two previously defined T cell epitopes were studied using T cell hybridomas specific for 308-319/Ad, associated with the cell wall on the surface of streptococci, and 17-31/Ed, located at the protruding amino terminus of M5. Studies with metabolic inhibitors showed that slow (1 h) processing of M5 308-319 occurred in late endosomes and was dependent on newly synthesized MHC class II molecules and microtubules and on communications between early and late endosomes, consistent with engagement of the classical MHC class II processing pathway. In contrast, fast (15 min) bacterial Ag processing of 17-31 occurred in early endosomes independently of newly synthesized MHC class II molecules and microtubules and of trafficking between early and late endosomes, consistent with the recycling MHC class II processing pathway. Finally, bacterial Ag processing of the epitopes exhibited differential sensitivity to blocking with anti-MHC class II Abs. Thus, two T cell epitopes of a single protective Ag from the surface of whole bacteria are routed to distinct MHC class II processing pathways.     

Influence of obstructive jaundice on jejunal absorption of glucose, electrolytes, and vitamin A in rats

Jejunal absorption of glucose, electrolytes, and vitamin A was investigated in rats. A Tyrode solution containing glucose, sodium, and potassium in concentrations two and four times higher than usual was infused through the jejunal loops of jaundiced and control rats during 40 min. The glucose values in the influx and effluent were not different during the experiment time. However, the concentrations of sodium and potassium of the effluent decreased with concentrations twice normal. The osmotic pressure of the effluent was directly related to the electrolytic concentration. When the perfusate fluid was four times higher, the differences between sham and jaundiced groups remained unchanged. The osmotic pressure means of the jaundiced group decreased during the experimental time. The absorption of vitamin A increased during the 40-min experiment time in the control rats. On the other hand, vitamin A concentration in the perfused lumen of the jaundiced group did not change over the time. These data indicate that obstructive jaundice has little influence on glucose and electrolytes absorption, while vitamin A is impaired by this condition.