Inflammatory pseudotumor of the liver: appearance on MRI.

Inflammatory pseudotumor of the liver is a rare entity; fewer than 50 cases have been reported in the world literature. Its appearance on both computerized tomography (CT) and ultrasound have been previously described. To our knowledge, this is the first report of its appearance on magnetic resonance imaging (MRI). The lesion demonstrated increased signal intensity on T-1 and T-2 spin-echo and inversion recovery (STIR) sequences in relationship to normal liver. The signal characteristics, however, were nonspecific and diagnosis required biopsy confirmation. There was spontaneous resolution with conservative management, and this was documented on follow-up CT and MRI.

Radiologic case study. Intraspinal lumbar synovial cyst.

In conclusion, intraspinal lumbar synovial cysts are uncommon causes of sciatic pain. Intraspinal synovial cysts are associated with degenerative arthritis of the lumbar spine. The radiographic findings on myelography are non-specific, but CT and MRI are helpful in establishing the diagnosis and in differentiating synovial cysts from other extradural lesions.

Effect of acute and repeated chlordimeform treatment on rat hepatic microsomal drug metabolizing enzymes.

The effect of chlordimeform treatment on the hepatic microsomal drug metabolizing enzymes was examined in male and female rats following either acute or repeated treatment. After acute administration of chlordimeform (100 mg/kg, ip one hr prior to sacrifice) differential effects were observed in various parameters of the hepatic microsomal mixed function oxidase system with significant decreases in ethylmorphine metabolism, cytochrome P-450 content, NADPH cytochrome c reductase, and in the spectral binding of hexobarbital and aniline while no changes were found in the metabolism of aniline or p-nitroanisole. Durations of zoxazolamine-induced paralysis and pentobarbital-induced hypnosis were increased significantly after acute chlordimeform administration. Following repeated administration of chlordimeform (75 mg/kg ip for four days) to adult male rats, a decrease was observed in zoxazolamine-induced paralysis time while pentobarbital-induced hypnosis was not altered. Metabolism studies using isolated hepatic microsomal fractions showed a decrease rate of biotransformation of ethylmorphine and aniline while the activity of p-nitroanisole O-demethylase was not changed. No differences were found in cytochrome P-450 levels whereas microsomal spectral binding of hexobarbital was reduced while that of aniline was not affected. Following acute or repeated administration of chlordimeform to adult female rats, decreases in the hepatic microsomal metabolism of aniline, but not ethylmorphine or p-nitroanisole, were observed. Addition of chlordimeform to microsomal suspensions yielded a Type I spectral binding curve.

Effect of acute and repeated chlordimeform treatment on rat hepatic microsomal drug metabolizing enzymes.

The effect of chlordimeform (CDM) treatment on the hepatic microsomal drug metabolizing enzymes was examined in male and female rats following either acute or repeated treatment. After acute administration of chlordimeform (100 mg/kg, i.p., 1 hour before killing) differential effects were observed in various parameters of the hepatic microsomal mixed function oxidase system with significant decreases in ethylmorphine metabolism, cytochrome P-450 content, NADPH cytochrome c reductase, and in the spectral binding of hexobarbital and aniline while no changes were found in the metabolism of aniline or p-nitroanisole. Durations of zoxazolamine-induced paralysis and pentobarbital-induced hypnosis were increased significantly after acute CDM administration. Following repeated administration of CDM (75 mg/kg, i.p., for 4 days) to adult male rats, a decrease was observed in zoxazolamine-induced paralysis time while pentobarbital-induced hypnosis was not altered. Metabolism studies using isolated hepatic microsomal fractions showed a decreased rate of biotransformation of ethylmorphine and aniline while the activity of p-nitroanisole O-demethylase was not changed. No differences were found in cytochrome P-450 levels whereas microsomal spectral binding of hexobarbital was reduced while that of aniline was not affected. Following acute or repeated administration of CDM to adult female rats, decreases in the hepatic microsomal metabolism of aniline, but not ethylmorphine or p-nitroanisole, were observed. Addition of CDM to microsomal suspensions yielded a Type I binding curve.