The frequency and degree of periportal high intensity (PHI) on T2-weighted images in 28 patients (32 MR studies) with acute viral hepatitis were analyzed with regard to the various levels of serum glutamic-oxaloacetic transaminase (SGOT) and clinical phases. Periportal high intensity was found in 16 of 32 MR studies (50%) and no definite PHI was found in 7 studies (22%). Periportal high intensity appeared when the SGOT level was greater than 500 IU or when the phase of the disease was early. Follow-up studies revealed that PHI decreased during clinical recovery. We conclude that the degree of PHI on T2-weighted images reflects the severity of the disease in acute viral hepatitis.

Acute Disease↗

PubMedDate not supplied

Immunohistochemical detection of cytokeratin 18 and its neo-epitope in Warthin's tumor (adenolymphoma) of the parotid glands.

An immunohistochemical method using a monoclonal antibody M30 (MAb M30), which reacts with the product released by cleavage of cytokeratin 18 (CK18) by activated caspase, was used to investigate the presence and extent of apoptosis in 36 cases of Warthin's tumor (WT) of the parotid glands. The distribution of CK18 in WT was also determined and compared with that of the product detected by MAb M30. In WT, CK18 was observed mainly in the tumor cells of duct-like structures, but not in the cells of lymphatic tissues. Positive MAb M30 reaction products were found in luminal contents, duct-like structures and the cytoplasm of some macrophages in lymphatic areas near the duct-like structures in WT. These findings indicated that apoptotic cells are phagocytosed and eliminated as waste by macrophages. It is suggested that a mechanism which regulates the balance of proliferative activity and apoptosis may be closely linked to the growth of WT.

Adenolymphoma↗

PubMedDate not supplied

A septum-like structure of the gallbladder in acute viral hepatitis: CT demonstration.

We present two patients with a septum-like structure of the gallbladder on CT. The patients were hospitalized with acute viral hepatitis. CT performed within a week from the onset of symptoms demonstrated a high density linear structure in the gallbladder mimicking a septum. This structure seemed to be produced by a marked thickening of the gallbladder wall. It disappeared during the clinical recovery.

Acute Disease↗

PubMedDate not supplied

6-Fluoro-2-methylspiro(chroman-4,4'-imidazolidine)-2',5'-dione and related compounds as inducers of monooxygenase in rat liver microsomes.

The relationship between the structure of spirohydantoin derivatives and their inducing effects on hepatic monooxygenase system was studied. At the dose of 1 mumol/kg (0.3 mg/kg), 6-fluoro-2-methylspiro(chroman-4,4'-imidazolidine)-2',5'-dione (M79175) was found to exhibit an inducing effect on benzphetamine N-demethylase. On the contrary, the inducing effect of Sorbinil, in which the 2-methyl group on the chroman ring of M79175 was replaced by hydrogen atom, on benzphetamine N-demethylase was 100 times less than that of M79175. The substitution of the methyl group of M79175 with the dimethyl group did not affect the inducing effect, whereas the substitution with the hexyl group resulted in the loss of the inducing effect on drug oxidation activities tested at a dose of 10 mg/kg. Furthermore, cyclohexane spiro-2,6-chloro-1'-(3-dimethylaminopropyl)spiro(chroman-4,4'-imidazolid ine)-2' , 5'-dione (M79193) had an inducing effect on total cytochrome P-450 content, but had no inducing effect on benzphetamine N-demethylase. In addition, M79175 was found to induce cytochrome P-450 which is immunochemically related to one of the major forms of phenobarbital-inducible cytochrome P-450 (P-450(PB-1], but not cytochrome P-450 which is immunochemically related to the major form of 3-methylcholanthrene-inducible cytochrome P-450 (P-450(MC-1]. On the other hand, M79193 was found to induce neither P-450(PB-1) nor P-450(MC-1).

Animals↗

PubMedDate not supplied

Cytochrome P450 isozymes involved in propranolol metabolism in human liver microsomes. The role of CYP2D6 as ring-hydroxylase and CYP1A2 as N-desisopropylase.

Oxidative metabolic pathways of propranolol consist of naphthalene ring-hydroxylations (at the 4-, 5-, and 7-positions) and side-chain N-desisopropylation in mammals. We characterized cytochrome P450 isozymes responsible for propranolol metabolism, especially N-desisopropylation and 5-hydroxylation, in human liver microsomes. 4-Hydroxy, 5-hydroxy-, and N-desisopropylpropranolol were detected as primary metabolites, whereas 7-hydroxypropranolol was in trace amounts. Good correlations were obtained for activities of propranolol 4- and 5-hydroxylases with immunochemically determined CYP2D6 content, whereas correlations of these activities with CYP1A2, CYP2C, or CYP3A4 content were relatively low. The activities also correlated highly with debrisoquine 4-hydroxylase, compared with other metabolic activities such as phenacetin O-deethylase, hexobarbital 3'-hydroxylase, and testosterone 6 beta-hydroxylase, which are typical reactions for CYP1A2, CYP2C, and CYP3A4, respectively. Propranolol N-desisopropylase activity in the samples highly correlated with CYP1A2 content and phenacetin O-deethylase activity, but not with the other P450 isozyme contents or metabolic activities. Quinidine, a specific inhibitor of CYP2D6, inhibited propranolol 4- and 5-hydroxylase activities selectively and in a concentration-dependent manner. alpha-Naphthoflavone, a potent inhibitor of CYP1A2, inhibited all of the propranolol oxidation activities, and the IC50 value for N-desisopropylase activity was much smaller than the values for ring-hydroxylase activities. Antibody directed to CYP2D inhibited propranolol 4- and 5-hydroxylase activities by 70% at an antibody/microsomal protein ratio of 1.0. Anti-CYP2C9 antibody did not inhibit any activity determined. These results indicate that propranolol 5-hydroxylation, as well as 4-hydroxylation, is mainly catalyzed by CYP2D6 in human liver microsomes.(ABSTRACT TRUNCATED AT 250 WORDS)

Benzoflavones↗