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Bile acids are produced by the liver and released into the small intestine in response to a meal; they aid in the efficient absorption of dietary fat and cholesterol. The bile acids are reabsorbed at a more distal point in the intestine, after they have accomplished their function, and return to the liver via the bloodstream where they await reentry into the cycle. The release and reabsorption of bile acids are part of a tightly controlled feedback cycle in which the rate of bile acid biosynthesis is regulated by both the demand for these compounds by the digestive tract and the rate at which they return to the liver. Ursodeoxycholic acid, a derivative of the major bile acids (and itself a minor constituent of bile) has been used in the treatment of a variety of disorders, including gall stones, primary biliary cirrhosis, and sclerosing cholangitis. The extent to which beneficial effects of ursodeoxycholic acid treatment may be related to its influence on intestinal absorption of bile acids is not known. To further investigate this issue, a newly available tracer technique involving monitoring the absorption of radioactively labelled selenium homocholic acid taurine (an easily measurable analog of naturally occurring bile acids) was used to quantify the effects of ursodeoxycholic acid on bile acid absorption. The radiolabelled acid was given orally, and bile acid absorption inferred from the rate of disappearance of radioactivity over a seven-day period. This was done before and after three weeks of treatment with ursodeoxycholic acid. Following treatment, there was a significant decrease in intestinal absorption of bile acids and blood cholesterol levels; blood levels of ursodeoxycholic acid increased. These results suggest that the beneficial effects of ursodeoxycholic acid treatment result, at least in part, from its suppressive actions on the absorption of bile acids. (Consumer Summary produced by Reliance Medical Information, Inc.)

Background: AI (Avian influenza) refers to a large group of different influenza viruses that primarily affect birds. On rare occasions, these bird viruses can infect other species, including pigs and humans. The vast majority of avian influenza viruses do not infect humans. Objective: To assess knowledge, attitude and practices related to AI among poultry workers. Methodology: A descriptive cross sectional study was designed to conduct in Bangladesh with a pretested modified questionnaire by face to face interview. Result: Current study revealed that nearly one third of the respondents were belonged to age group 26-30 years (39.17%) with the mean age 32.18±6.65 years. Majority of the respondents were male (70%). Nearly two thirds (80%) were owners of poultry farms. Half of them (49.67%) got information regarding AI by electronic media. Nearly one third of the study respondents (34.17%) replied that hand washing after poultry care and less than one third of the respondents (31.67%) said by using PPE (Personal Protective Equipment) during poultry care can prevent AI. Most of the participant said that they informed Rapid Response Team (RRT) for management of sick or dead poultry. More than half of the respondents (57.5) were using PPE. Association found between Socio-demographic variable (Age) and Knowledge on preventing avian influenza among the respondents where p-value=0.001. Conclusion: Knowledge and practices about AI disease among the poultry workers was moderate, but their attitudes were positive. Therefore, designing and implementing health educational programs and ensure proper training for poultry workers about AI to improve preventive practices should have the priority to eliminate the disease. [ABSTRACT FROM AUTHOR]

A mouse model of insulin resistance and its associated dyslipidemia was generated by crossing mice expressing human apolipoprotein B (apoB) with mice lacking only brown adipose tissue (BATless). On a high fat diet, male apoB/BATless mice became obese, hypercholesterolemic, hypertriglyceridemic, and hyperinsulinemic compared with control apoB mice. Fast performance liquid chromatography revealed increased triglyceride concentrations in intermediate density lipoprotein/low density lipoprotein (LDL) and reduced high density lipoprotein cholesterol concentrations. Inhibition of lipolysis by the drug, tetrahydrolipostatin, demonstrated that very low density lipoprotein-sized particles were initially secreted. Metabolic studies employing Triton WR-1339 and either [(3)H]glycerol or [(3)H]palmitate showed that the hypertriglyceridemia in apoB/BATless mice was due to the increased synthesis and secretion of triglyceride. Furthermore, lipoprotein lipase and hepatic lipase activities were not defective. ApoB was also secreted at increased rates in the apoB/BATless mice. Similar levels of apoB mRNA in apoB and apoB/BATless mice indicated that apoB secretion was regulated post-transcriptionally. LDL receptor mRNA was increased in the apoB/BATless mice, indicating that the observed increase in apoB-lipoprotein secretion was not due to their decreased reuptake. Finally, mRNA levels of the large subunit of microsomal triglyceride transfer protein, a required component for very low density protein assembly, were not different between apoB and apoB/BATless mice. This rodent model should prove useful in exploring mechanisms underlying the regulation of apoB secretion in the context of insulin resistance.

Cyclosporine (CsA) and tacrolimus (FK506) have recently been reported to inhibit canalicular transport of bile acids in vitro and thereby possibly induce cholestasis. A relative reduction of chenodeoxycholic acid (CDCA) has been observed after liver transplantation when CsA is used as immunosuppressant. We tested the hypothesis that CsA induces cholestasis and reduces CDCA secretion as compared with treatment with monoclonal antibodies (OKT3), and that CsA differs from FK506 with regard to its effects on biliary lipid secretion. Bile flow, biliary lipid secretion rates, and biliary bile acid composition were determined during the first 10 days after transplantation in 29 liver transplant recipients. Two prospective randomized studies were performed that compared CsA and OKT3 and compared CsA- and FK506-based regimens. In study 1, bile acid output averaged 0.75+/-0.15 micromol/min in the CsA I group and 0.54+/-0.11 micromol/min in the OKT3 group on postoperative day 1. Bile flow and bile acid output then increased, and there was no significant difference between the two groups. The relative proportion of CDCA decreased to the same extent in both groups. In study 2, mean bile acid outputs on postoperative day 1 were 0.57+/-0.26 micromol/min and 0.55+/-0.15 micromol/min in the CsA 2 and FK506 groups, respectively. The following increase in bile acid secretion was significantly larger in the FK506 group. After transplantation, the relative proportion of CDCA decreased with time in both groups, but the reduction was more rapid in the FK506 group. In conclusion, CsA did not inhibit bile secretion during short-term treatment after liver transplantation. Compared with patients given CsA-based treatment, patients with FK506-based treatment recovered bile secretion more rapidly.

Bile acid malabsorption is often due to a disease or partial resection of the terminal ileum and more rarely a genetic defect in the distal ileum. It is often associated with diarrhoea with or without steatorrhoea, and it may be complicated by gallstone disease and hyperoxaluria. Bile acid malabsorption is rather easily diagnosed using the selenohomocholic acid taurine test. Patients with bile acid induced diarrhoea should be recommended a low-fat diet. Cholestyramine may be recommended in moderate bile acid diarrhoea. In patients with more severe bile acid malabsorption, cholylsarcosine may be used as a replacement therapy.

Biliary lipid metabolism was studied after 10 liver transplantations with continuous drainage of bile. Within 3 wk after transplantation, the new liver produced bile with concentrations of biliary lipids in agreement with those reported for T-tube bile in cholecystectolized nontransplanted subjects. Although changes in biliary lipid composition occurred swiftly in response to various forms of disturbed liver function, they did not provide substantially more information than did standard serum tests or simple measurements of bile flow in most patients. Secretion rates of phospholipids and cholesterol were found to be completely bile acid dependent. For each micromole of bile acids, 0.22 and 0.08 mumol of phospholipids and cholesterol were secreted, respectively. When bile flow was related to bile acid output, a linear relationship was found (r = 0.89), with a positive intercept indicating a bile acid-independent bile flow of approximately 44 microliters/min. Analysis of individual bile acids showed almost exclusively primary bile acids. The relative proportion of chenodeoxycholic acid was more prominent during the first days after transplantation. Different explanations for this are discussed.