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Mohs paste is an external preparation containing zinc hydrochloride and zinc oxide starch as the main ingredient, and it is used for the palliative treatment of patients with surgically untreatable malignant tumors. However, it has problems, such as changes in hardness and viscoelasticity with time and liquefaction by exudate. To overcome these problems, we modified the formulation of Mohs paste by excluding starch, which is the cause of physical changes, and investigated the base. In the modified Mohs paste using the macrogol ointment for the base, no marked change with time was noted in the hardness, malleability, or elongation property, and the water-absorbing properties were equivalent to those of Mohs paste immediately after preparation. The hardness did not decrease even after absorbing water. The drug release rate increased 1.5 times with the modified Mohs paste. Based on these findings, the risk of liquefaction-associated damage of the surrounding skin decreased on using the modified Mohs paste, and preparing in advance became possible. These results suggest that the modified Mohs paste using the macrogol ointment for the base exhibits an equivalent effect for control of exudate and a high effect for tissue fixation.

We observed previously that polychlorinated biphenyl (PCB) could be classified to two groups, 3-methylcholanthrene (MC)-type and phenobarbital (PB)-type, in term of inducibility of the hepatic enzymes. MC-type PCBs such as 3,4,3',4'-tetrachlorobiphenyl (TCB), 3,4,5,3',4'-pentachlorobiphenyl (PenCB) and 3,4,5,3',4',5'-hexachlorobiphenyl (HexCB) exhibited high acute toxicity in parallel with their induction ability of microsomal benzo[a]pyrene 3-hydroxylase and cytosolic DT-diaphorase. On the contrary, PB-type PCBs such as 2,5,2',5'-TCB and 2,4,5,2',4',5'-HexCB which induce microsomal benzphetamine N-demethylase and NADPH-cytochrome P-450 reductase activities showed virtually no or very low toxicity. In the present study, we examined effects of 2,5,2',5'-TCB and its major metabolite 3-hydroxy-2,5,2',5'-TCB on body weight gain, organ weights and activities of hepatic enzymes in rats and assessed acute toxicity of these compounds. As the results, in both 2,5,2',5'-TCB and 3-hydroxy-2,5,2',5'-TCB groups, the body weights were increased during the experiment, but the rate of growth was significantly suppressed after 3 days. Significant hypertrophy of the liver and decrease of total liver lipid content were observed in 2,5,2',5'-TCB group, but the atrophy of spleen and thymus was not affected in both groups. On the other hand, in 2,5,2',5'-TCB group, benzo[a]pyrene 3-hydroxylase and benzphetamine N-demethylase activities were increased to 2. 4-fold and 1.5-fold, respectively, but were not increased in 3-hydroxy-2,5,2',5'-TCB group. After injection of 2,5,2',5'-TCB, 45% of the dose was excreted as 3-hydroxy-2,5,2',5'-TCB in feces for 5 days.(ABSTRACT TRUNCATED AT 250 WORDS)