Transition between solar keratosis and basal cell carcinoma.

Transition from solar keratosis (SK) to squamous cell carcinoma (SCC) is well known and vastly documented. The possible relation between SK and basal cell carcinoma (BCC) is rarely mentioned in the dermatopathological literature. In order to identify the characteristics of the relation between SK and BCC, 40 slides of the head and neck regions in which both SK and BCC had been diagnosed, were retrieved from a collection in the Institute of Pathology of Beilinson Medical Center, seen between 1984 and 1994. Gradual and continuous transition between SK and BCC was found in 15 (37.5%) of these 40 slides. In order to estimate the prevalence of this phenomenon, 73 additional slides, which had been diagnosed as BCC of the head and neck, were re-examined. Atypia of the spinous layer, as an initial marker for the development of SK, was sought in each slide. Revision revealed spinous layer atypia in 26 (35.6%) slides, in addition to the previously diagnosed BCC. In seven (9.6%) the transition between atypical spinous cells and BCC was gradual and continuous. A gradual and continuous transition between SK and BCC can be explained by the presence of pluripotent stem cells in the epidermis. Stem cells, following malignant transformation, may differentiate in different directions, resulting in both SK and BCC.

Effects of some hypolipidemic drugs on biochemical values and on hepatic peroxisomal enzymes of normolipemic rat.

Effects of vitamin B2-butyrate, nicomol, ML-236B, KF 1492 and pantethine, which are hypolipidemic drugs, on biochemical values and on hepatic peroxisomal enzymes of normolipemic rat. 1) Vitamin B2-butyrate (100 mg/kg) and nicomol (lg/Kg) increased carnitine acetyltransferase and D-amino acid oxidase activities, respectively, while these drugs had no influence on body weight, liver weight, serum and liver triglyceride, and serum and liver cholesterol levels. 2) ML-236B (300 mg/kg) had no influence on biochemical values and on activities of peroxisomal enzymes containing catalase. 3) KF 1492 (300 mg/kg) had no influence on the biochemical values, but an increase in the activities of fatty acyl-CoA oxidizing system (FAOS) and carnitine acetyltransferase (CAT) participating hepatic lipid metabolism was observed. 4) Pantethine (lg/kg) had no influence on the biochemical values, except a little decrease in the growth rate. However, increase by about 10% in the activities of urate oxidase and D-amino acid oxidase was observed. Catalase activity was decreased to 60% of control level. From these results, it is concluded that, in contrast to clofibrate, vitamin B2-butyrate, nicomol, ML-236B, KF 1492 and pantethine have little influence on the lipid metabolism of normolipemic animal and on the hepatic peroxisomal enzymes, indicating that the action mechanism of these drugs may be different from that of clofibrate and that the participation of hepatic peroxisomes in hypolipidemic activities of these drugs may be little if any.