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Bile Acid Concentration (bile + acid_concentration)
Selected AbstractsSerum Bile Acids Concentrations in Healthy and Clinically III Neonatal FoalsJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 3 2007Michelle Henry Barton Background:Reference ranges for serum bile acids (SBA) concentration are well established in healthy adult horses. Increased values are indicative of hepatic disease. Hypotheses: SBA concentrations are significantly greater in the neonatal period compared with mature horses, and illness in the neonatal period will further increase SBA. Animals:Ten healthy mature horses, 12 healthy foals, and 31 clinically ill foals. Methods:Prospective cross-sectional study. Blood samples were obtained once from the mature horses, from healthy foals immediately after birth, at 2 days, and at 1, 2, 3, 4, and 6 weeks of age; and from ill foals less than 1 month of age at the time of admission to the Veterinary Teaching Hospital. SBA concentrations were determined enzymatically and by radioimmunoassay. Total and direct bilirubin and triglyceride concentrations were measured, as well as sorbitol dehydrogenase (SDH) and ,-glutamyltransferase (GGT) activities. Results:There was a significant negative correlation between age and SBA concentration. Compared with mature horses, SBA concentrations were significantly greater in healthy foals at each collection time over the first 6 weeks of life. Radioimmunoassay values were lower than enzymatic SBA values, with increasing bias as the mean difference between values increased. When comparing age-matched values between healthy and ill foals, there were no significant differences in SBA. None of the ill foals had a primary diagnosis of hepatic disease. There was no significant correlation between the SBA concentration and the bilirubin or triglyceride concentrations or the GGT activity. There was a significant direct correlation between increased SBA and serum SDH activity in healthy foals only. Conclusion and Clinical Importance: SBA concentrations in foals are significantly higher in the early neonatal period, underscoring the importance of using age-matched references when evaluating clinical pathology values during the neonatal period. [source] Reflux and pH: ,alkaline' components are not neutralized by gastric pH variationsDISEASES OF THE ESOPHAGUS, Issue 1 2000P. Bechi The ability of the ,alkaline' components of reflux to cause harm in vivo is still open to debate, although these components have been shown in vitro to be capable of damaging the mucosa. The precipitation of bile acids and lysolecithin that occurs at low pH values is the main reason for questioning in vivo mucosal damage. This study was undertaken to determine the composition of gastric aspirates at different original pH values and the degree of solubility of the alkaline components when pH modifications are artificially induced. The samples for chemical analysis were collected from indwelling nasogastric tubes after surgical procedures that did not involve the upper gastrointestinal tract. Bile acid and lysolecithin concentrations were assessed by means of dedicated methods. Thirty-five samples were available for bile acid evaluation and 27 for lysolecithin evaluation. Bile acid and lysolecithin assessments were repeated after pH adjustment at 2, 3.5, 5.5 and 7. For easier assessment of the results, three ranges of the original pH were selected (pH,<,2, 2 , pH < 5, pH , 5). For each pH range, results were pooled together and compared with those in the other pH ranges. Bile acid concentrations were 113 ± 48, 339 ± 90 and 900 ± 303 (mean ± s.e.m. ,mol/L), respectively, in the three groups selected on account of the different original pH values. Differences were significant (p < 0.001). Both taurine- and glycine-conjugated bile acids were represented even at pH < 2. No major differences were observed in bile acid concentration with the artificially induced pH variations. Lysolecithin concentrations were 5.99 ± 3.27, 30.80 ± 8.43 and 108.37 ± 22.17 (mean ± SEM ,g/ml), respectively, in the three groups selected on account of the different original pH ranges. Differences were significant (p < 0.001). No significant differences in lysolecithin concentration were detected with the artificially induced pH variations. In conclusion, both bile acids and lysolecithin are naturally represented in the gastric environment even at very low pH values, although their concentrations decrease on lowering of the naturally occurring pH. Given the concentration variability of bile acids and lysolecithin, further studies are needed to assess the minimal concentration capable of mucosal damage in vivo. [source] Drug metabolic activity of cultured hepatocytes can synchronize with bile acid concentration in the mediumCELL BIOCHEMISTRY AND FUNCTION, Issue 1 2002Nobuhiro Sugihara Abstract The regulation of drug metabolic activity of cultured hepatocytes can be applied to the evaluation of pharmacokinetics, analysis of drug delivery and the bioartificial liver system. It is very difficult to maintain the drug metabolic activity mediated by cytochrome P-450 (CYP) 3A. Recently we found that the CYP3A aminopyrine N-demethylase (AMND) activity of hepatocytes cultured on collagen surface oscillated with culture time. This phenomenon was related to the concentration of bile acid in the culture medium. CYP3A, multidrug resistant gene 2 (MDR2) and heat shock protein 84 (HSP84) mRNA appeared in a manner corresponding to this oscillation. When a large quantity of bile acid was taken up into hepatocytes from the medium, low AMND activity was observed, and these proteins did not appear. When bile acid was secreted and the bile acid concentration inside the hepatocytes was low, high AMND activity was obtained, and these proteins appeared. In order to clarify the mechanism of oscillation between AMND activity and bile acid, 8,,M glycocholic acid was added to the culture medium 15,h before the measurement. No oscillation in AMND activity was observed in the presence of 8,,M glycocholic acid. Bile acid controls the AMND activity in the transcription of hepatocytes. Copyright © 2001 John Wiley & Sons, Ltd. [source] Elevated plasma bile acid concentrations in two sisters with tyrosinaemia type IJOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 1 2000JO Sass Abstract: A 21-month-old girl suffering from tyrosinaemia type I and undergoing treatment with 2-(2-nitro-4-trifluoromethylbenzoyl)-1,3-cyclohexanedione (NTBC) presented with pruritus which rapidly ceased with administration of high doses of ursodeoxycholic acid. Determination of plasma bile acids revealed clearly elevated levels both in samples taken before and after the onset of NTBC therapy, thus indicating, that the increase was not related to the administration of this drug. This result is corroborated by data from the first patient's newborn sister, diagnosed with the same disease, who showed elevated plasma bile acid concentrations in all samples examined, except for the cord plasma. This is the first report on altered bile acid concentrations in tyrosinaemia type I, and underlines the need for thorough investigation of bile acid metabolism in this disease. [source] Enhanced bioavailability of a new thiazolidine derivative FPFS-410, an antidiabetic and lipid-lowering drug, after oral administration of its hydroxypropyl-,-cyclodextrin complex to bile duct-cannulated ratsJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 8 2006Takumi Hara Abstract The effect of bile acids on bioavailability of FPFS-410 (2-(N -Cyanoimino)-5-{(E)-4-styrylbenzylidene}-4-oxothiazolidine) after oral administration of the drug and its 2-hydroxypropyl-,-cyclodextrin (HP-,-CyD) complex was investigated. The complexation with HP-,-CyD increased the oral bioavailability of FPFS-410 in normal rats in a HP-,-CyD concentration-dependent manner, compared with that of drug alone. In bile duct-cannulated rats, bile acid concentrations in pylic serum and biliary were decreased to 18% and 14% of sham-operated rats, respectively. After oral administration of the HP-,-CyD complex, the plasma levels of FPFS-410 were lower in bile duct-cannulated rats than in sham-operated rats up to 1 h, however, this order reversed from 2 to 12 h. The plasma levels of M1, a dominant metabolite of FPFS-410 in rats, significantly decreased until 2 h after administration of the complex in bile duct-cannulated rats, compared with in sham-operated rats. Bioconversion of FPFS-410 to M1 and CYP3A2 expression in the liver was markedly lowered by bile duct-cannulation. Bile duct-cannulation did not, however, affect the serum levels of estradiol. These results suggest that bile acids have a pivotal role for bioavailability of FPFS-410 after oral administration of the FPFS-410 complex with HP-,-CyD through CYP3A2 activity in liver of rats. © 2006 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 95: 1771,1782, 2006 [source] | ||||||||||