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Biomedical subjects

H Takikawa

Publications and source records attributed to H Takikawa.

At least 37 records · Page 2Linked to original sources
PubMed1999

Recent status of primary sclerosing cholangitis in Japan.

Patients with primary sclerosing cholangitis (PSC) in Japan have two peaks in age distribution, one in their twenties and the other in their fifties and sixties. PSC patients in Japan have different characteristics from those in other countries: there is a higher incidence of eosinophilia (27%) and positivity for anti-nuclear antibody (30%), less frequent complication with inflammatory bowel diseases (IBD; 21%), and more frequent complication with chronic pancreatitis (15%). In younger patients in Japan (those aged less than 40 years), the incidence of positivity for anti-nuclear antibody was lower (20% vs 38% P < 0.05), complication with IBD was more frequent (39% vs 9% P < 0.01), complication with chronic pancreatitis was less frequent (4% vs 22% P < 0.01), and damage to both the intra- and extrahepatic bile ducts was more frequent (89% vs 56% P < 0.01) than in older patients (those aged 40 years or more). These findings suggest that younger PSC patients in Japan have characteristics similar to those of patients in other countries, and that in Japan older PSC patients have a different pathogenesis from that of younger patients.

Adult↗
PubMed1999

Epstein-Barr virus infection resembling autoimmune hepatitis with lactate dehydrogenase and alkaline phosphatase anomaly.

A 73-year-old man had fever, lymphadenopathy, granulocytopenia, thrombocytopenia, ascites, pleural effusion, liver injury, and an allergic-like skin rash. Autoantibodies, such as anti-nuclear antibody, were shown, and there were lactate dehydrogenase and alkaline phosphatase anomalies and platelet-associated IgG. His liver injury resembled that in autoimmune hepatitis. He was diagnosed with Epstein-Barr virus (EBV) infection associated with autoimmunization because of his clinical course, fluctuation of anti EBV antibodies and positive EBV genome in circulating lymphocytes and serum. This case suggests a close relationship between EBV infection and autoimmunization or autoimmune-like hepatitis.

Aged↗
PubMed1999

Effect of organic anions and bile acid conjugates on biliary excretion of taurine-conjugated bile acid sulfates in the rat.

Biliary organic anion excretion is mediated by an ATP-dependent primary active transporter, canalicular multispecific organic anion transporter/multidrug resistance protein 2. On the other hand, a multiplicity of canalicular organic anion transporter/multidrug resistance protein 2 has been suggested. Therefore, to examine the effect of hydrophobicity on the substrate specificity of canalicular multispecific organic anion transporter/multidrug resistance protein 2, we examined the effect of organic anions and bile acid conjugates on biliary excretion of three taurine-conjugated bile acid sulfates with different hydrophobicity, taurolithocholate-3-sulfate, taurochenodeoxycholate3-sulfate, and taurocholate-3-sulfate in rats. Biliary excretions of these bile acid conjugates were delayed in Eisai hyperbilirubinemic rats. Biliary excretion of these bile acid conjugates was inhibited by sulfobromophthalein, whereas biliary excretion and taurocholate-3-sulfate was not inhibited by phenolphthalein glucuronide. Taurolithocholate-3-sulfate and ursodeoxycholate-3-glucuronide decreased biliary excretion of taurochenodeoxycholate-3-sulfate and taurocholate-3-sulfate, but ursodeoxycholate-3,7-disulfate did not affect biliary excretion of taurochenodeoxycholate-3-sulfate and taurocholate-3-sulfate. These findings indicate that very hydrophilic organic anions are not good substrates of canalicular multispecific organic anion transporter/multidrug resistance protein 2.

Animals↗
PubMed1999

Enzymatic resolution of (+/-)-gamma-cyclohomogeraniol and conversion of its (S)-isomer to (S)-gamma-coronal, the ambergris odorant.

Enzymatic acetylation of (+/-)-gamma-cyclohomogeraniol[2-(2',2'-dimethyl-6'-methylenecyc lohexyl)ethanol] with vinyl acetate in the presence of lipase AK yielded the acetate of its (R)-isomer, leaving its (S)-isomer intact. The (S)-isomer was chemically converted to (S)-gamma-coronal[2-methylene-4-(2',2'-dimethyl-6'-methylenecyclohexy l)butanal], the ambergris odorant.

Acyclic Monoterpenes↗
PubMed1999

Effects of organic anions and vinblastine on biliary excretion of erythromycin in rats.

Since little is known about the mechanism of biliary excretion of cationic drugs, biliary excretion of erythromycin was studied in rats. Infusion of sulfobromophthalein and taurocholate significantly decreased biliary erythromycin excretion, whereas infusion of dibromosulfophthalein, cefpiramide, ursodeoxycholate-3-O-glucuronide and taurolithocholate-3-sulfate had no effect on biliary excretion of erythromycin. Vinblastine significantly inhibited biliary erythromycin excretion. Phenothiazine treatment significantly increased biliary erythromycin excretion. However, erythromycin infusion did not affect biliary vinblastine excretion. These findings indicate a multiplicity of biliary excretory pathways for organic cations; at least one additonal pathway may exist for organic cations apart from P-glycoprotein.

Animals↗
PubMed1998

Effects of organic anions and bile acid conjugates on biliary excretion of pravastatin in the rat.

PURPOSE: Biliary organic anion excretion is mediated by an ATP-dependent primary active transporter, a so-called canalicular multispecific organic anion transporter (cMOAT). As there appear to be many canalicular organic anion transports, we examined the effects of various organic anions and bile acid conjugates on the biliary excretion of pravastatin in rats. METHODS: [14C]pravastatin was intravenously injected into rats with bile drainage in the presence and absence of the continuous infusion of organic anions and bile acids, and radioactivity of its biliary excretion was studied. RESULTS: Biliary excretion of [14C]pravastatin was markedly inhibited by sulfobromophthalein-glutathione, taurolithocholate-3-sulfate, ursodeoxycholate-3, 7-sulfate, and ursodeoxycholate-3-O-glucuronide. In contrast, dibromosulfophthalein only slightly inhibited biliary pravastatin excretion, and cefpiramide did not affect biliary pravastatin excretion. CONCLUSIONS: These findings further support the multiplicity of canalicular organic anion transport, and pravastatin is considered to be excreted through a canalicular transporter which is absent in EHBR in addition to through cMOAT.

Animals↗
PubMed1998

Enhanced biliary excretion of lithocholate-3-sulfate by ursodeoxycholate-3,7-disulfate infusion in Eisai hyperbilirubinemic rat (EHBR).

Biliary excretion of lithocholate-3-sulfate and ursodeoxycholate 3,7-disulfate is markedly impaired in EHBR. In the present study, the effects of ursodeoxycholate 3,7-disulfate infusion on lithocholate-3-sulfate excretion were studied in EHBR and Sprague-Dawley rats. Although in control rats, ursodeoxycholate 3,7-disulfate infusion had no effect on biliary lithocholate-3-sulfate excretion, in EHBR it enhanced biliary lithocholate-3-sulfate excretion. Although ursodeoxycholate 3,7-disulfate dose-dependently inhibited lithocholate-3-sulfate binding by rat serum albumin and rat liver cytosol, it did not affect the serum clearance of lithocholate-3-sulfate in EHBR in vivo. These findings indicate that in EHBR, in which the major ATP-dependent organic anion transporter is impaired, the excretory pathway for ursodeoxycholate 3,7-disulfate may interact to that for lithocholate-3-sulfate.

Animals↗
PubMed1998

Changes in biliary excretory mechanisms in rats with ethinyloestradiol-induced cholestasis.

Several excretory pathways for cholephilic compounds have been known. To examine the changes in excretory pathways in cholestasis induced by ethinyloestradiol, various bile acids, organic anions and organic cations were intravenously administered to ethinyloestradiol-treated rats and their biliary excretion was studied. Biliary excretion of taurocholate was slightly delayed, but its excretory maximum was markedly decreased. Biliary excretion of lithocholate-3-O-glucuronide, leukotriene C4, sulphobromophthalein and pravastatin was markedly impaired to a similar extent. Biliary excretion of vinblastine, a P-glycoprotein substrate, was increased, suggesting increased expression of P-glycoprotein. In contrast, biliary excretion of erythromycin, a cationic antibiotic, was markedly impaired. In conclusion, ethinyloestradiol treatment altered the biliary excretion of organic compounds, which may partly be related to changes of the canalicular transporters.

Animals↗
PubMed1998

Effects of colchicine and phenothiazine on biliary excretion of organic anions in rats.

Vesicular transport inhibitors have been reported to inhibit biliary excretion of some organic anions, suggesting that vesicular transport has a role in intracellular transport of these compounds. However, these inhibitors are substrates for P-glycoprotein. To examine whether P-glycoprotein has a role in canalicular transport of organic anions in addition to the canalicular multispecific organic anion transporter, we studied the effect of colchicine, a vesicular transport inhibitor, and phenothiazine to increase P-glycoprotein expression on biliary excretion of various organic anions in rats. Colchicine treatment slightly but significantly inhibited biliary excretion of indocyanine green, dinitrophenyl-glutathione and pravastatin, and had no effect on biliary excretion of sulphobromophthalein and dibromosulphophthalein. Phenothiazine treatment did not affect biliary excretion of indocyanine green and pravastatin, but it increased biliary sulphobromophthalein-glutathione excretion. In conclusion, the present findings suggest that P-glycoprotein plays an additive role on biliary excretion of some organic anions in addition to the canalicular multispecific organic anion transporter.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1997

Primary sclerosing cholangitis in Japan--analysis of 192 cases.

Primary sclerosing cholangitis is very rare in Japan. The aim of the present study was to identify the characteristics of such patients in Japan. A questionnaire was sent to the members of the Japanese Society of Gastroenterology and responses for 192 cases were analyzed. There was male predominancy (61%), and two peaks in the age distribution at diagnosis (20-30 years and 50-70 years). Bile duct damage was mainly intra + extrahepatic (69%) versus intrahepatic (17%) or extrahepatic (14%). The incidences of eosinophilia and positivity for anti-nuclear antibody were 27% and 30%, respectively. The incidence of associated inflammatory bowel disease was 21% (38 ulcerative colitis and 2 Crohn's disease). Chronic pancreatitis, gallstones, and biliary cancers occurred in 15%, 12%, and 4%, respectively, of the 192 patients. Patients less than 40 years of age had a higher incidence than the patients 40 years old or more of damage intra + extrahepatic bile ducts (89% vs 56%) and of associated ulcerative colitis (36% vs 9%), whereas the incidence of chronic pancreatitis was lower in patients aged less than 40 years (4%). The characteristics of patients with primary sclerosing cholangitis in Japan differ from those in other countries in regard to age distribution and the incidence of complications, and at least two different groups of patients seem to exist in terms of the degree of bile duct damage and the incidence of complications.

Adult↗
PubMed1997

Effects of organic anions and bile acid conjugates on biliary excretion of LTC4 in the rat.

Biliary organic anion excretion is mediated by an ATP-dependent primary active transporter, so-called canalicular multispecific organic anion transporter (cMOAT). On the other hand, a multiplicity of canalicular organic anion transport has been suggested. Therefore, to examine the substrate specificity of cMOAT using inhibition of excretion of [3H] LTC4-derived radioactive products in the bile as a marker, we examined the effects of various organic anions and bile acid conjugates on the biliary excretion of LTC4 in rats. Biliary excretion of the metabolites of [3H] LTC4, which was injected via the femoral vein, was markedly inhibited by sulfobromophthalein-glutathione, taurolithocholate-3-sulfate, and ursodeoxycholate-3-O-glucuronide. In contrast, dibromosulfophthalein and cefpiramide slightly inhibited, and pravastatin, taurocholate, and 3,7-sul-UDC did not affect biliary LTC4 excretion. Furthermore, vinblastine and phenothiazine, a P-glycoprotein substrate and inducer, did not affect biliary LTC4 excretion. Among various organic anions and bile acid conjugates, LTC4, sulfobromophthalein-glutathione, taurolithocholate-3-sulfate, and ursodeoxycholate-3-O-glucuronide may be good substrates for cMOAT.

Animals↗
PubMed1997

Effect of tauro-alpha-muricholate and tauro-beta-muricholate on oestradiol-17 beta-glucuronide-induced cholestasis in rats.

The effect of tauro-beta-muricholate (beta MC-tau) and tauro-alpha-muricholate (alpha MC-tau) on oestradiol-17 beta-glucuronide (E217G)-induced cholestasis was compared with that of tauroursodeoxycholate (UDC-tau) in rats. Like UDC-tau, alpha MC-tau and beta MC-tau infused at the rate of 0.2 mumol/min per 100 g bodyweight (BW) completely inhibited the cholestasis induced by E217G infused at the rate of 0.06 mumol/min per 100 g BW for 20 min. These findings indicate that beta MC-tau and alpha MC-tau are useful in protecting against various types of experimental cholestasis, as well as against bile acid-induced cholestasis.

Animals↗
PubMed1997

Absorption of unconjugated bile acids and tauroursodeoxycholate in the rat intestine.

The absorption of ursodeoxycholate and its tauro-conjugate by the jejunum and the terminal ileum of rat intestine was compared with that of other unconjugated bile acids and taurocholate. In the ligated jejunum, the efficacy of absorption of unconjugated bile acids was in the following order: ursodeoxycholate = deoxycholate > chenodeoxycholate = cholate > lithocholate. This order cannot be explained by the theory that the passive diffusion of bile acids is faster the less hydroxyl bonds in the molecule. These findings on the unconjugated bile acids in the ligated jejunum were further confirmed by perfusion experiments. In the ligated terminal ileum, ursodeoxycholate, cholate and deoxycholate were absorbed as fast as taurocholate or tauroursodeoxycholate, whereas absorption of chenodeoxycholate was significantly slower. The Na+-dependency of the absorption of ursodeoxycholate and cholate in the terminal ileum was confirmed by perfusion studies. In conclusion, intestinal absorption of ursodeoxycholate was efficient in both the jejunum and ileum and these results may contribute to the high availability of ursodeoxycholate in various hepatobiliary diseases.

Animals↗
PubMed1997

Effect of taurolithocholate-3-sulphate on biliary excretion of sulphobromophthalein and dibromosulphophthalein in the Eisai hyperbilirubinaemic rat.

We previously reported that biliary lithocholate-3-sulphate excretion was inhibited by dibromosulphophthalein, not by sulphobromophthalein in Eisai hyperbilirubinaemic rats (EHBR); instead its excretion was inhibited by both organic anions in control rats. In the present study, the effect of taurolithocholate-3-sulphate on the excretion of sulphobromophthalein and dibromosulphophthalein was studied in EHBR and control Sprague-Dawley rats. Taurolithocholate-3-sulfate infusion inhibited biliary excretion of sulphobromophthalein and dibromosulphophthalein in both EHBR and control rats. These findings indicate that in control rats biliary excretion of taurolithocholate-3-sulphate is mediated by a carrier common for both organic anions, and that in EHBR, in which the canalicular multispecific organic anion transporter is impaired, the excretory pathway for taurolithocholate-3-sulphate is also partly identical to that for both organic anions.

Animals↗