A method for isolation and quantification of fecal bile acids is described which allows sterol balance studies to be made in man or in small laboratory animals without requiring the use of radioisotopes in vivo. Bile acids are purified by column and thin-layer chromatography, converted to the trimethylsilyl ethers of their methyl esters, and quantified by GLC with detection by hydrogen flame io...

Faecal bile acids and neutral sterols of cholesterol origin were decreased in patients with chronic liver disease, while urinary bile acids were constantly, but never greatly, increased. Thus, production of cholesterol and its conversion to bile acids was decreased in these patients. Faecal fat was only slightly increased, even in cases with a very low bile salt output, but it was negatively co...

UNLABELLED Bile acids are considered as extremely toxic at the high concentrations reached during bile duct obstruction, but each acid displays variable cytotoxic properties. This study investigates how biliary obstruction and restoration of bile flow interferes with urinary and circulating levels of 17 common bile acids. Bile acids (conjugated and unconjugated) were quantified by liquid chroma...

The metabolism of bile acids in 30 pregnant women was evaluated by analyzing the urinary composition of bile acids during late gestation (weeks 30-41) and again in these women and their newborn infants during the first week after delivery. The levels of individual bile acids were determined by gas chromatography-mass spectrometry after solvolysis and hydrolysis of bile acid conjugates. The mean...

The structure of the bile acid molecule is described and correlated with physiochemical properties of bile acids such as solubility, ionization, and micelle formation. Recent measurements of the critical micellar concentration (CMC) of a large number of bile acids indicate that the CMC is influenced by both side chain and nuclear structure. Bile acids with hydroxy substituents on both sides of ...

Whereas cholesterol accounts for more than 90-95% of the sterols in bile, bile acids and their salts are the most important solutes; they are essential in the management of cholesterol levels and themselves help determine the extent of bile flow. Bile acids are synthesized from cholesterol in the liver. There are three groups. Primary bile acids, in humans mainly cholic and chenodeoxycholic aci...

Bile acids have been demonstrated, through the use of animal models and clinical association studies, to play a role in neoplastic development in Barrett's metaplasia. How specific bile acids promote neoplasia is as yet unknown, as are the exact identities of the important bile acid subtypes. The combination of bile subtype with appropriate pH is critical, as pH alters bile acid activity enormo...

Postoperative serum bile acids in a patient with hepatectomy were determined by gasliquid chromatography. The results showed that two high peaks of serum bile acid levels were found respectively on the 2nd and 7th postoperative day, although serum bile acid levels returned to normal after the 15th postoperative day. The high peaks were considered to be due to the escape of necrotic hepatic intr...

Duodenal bile acids have been estimated in three age groups in infancy from birth to 7 months, and age-related changes have been shown. The lowest concentrations of duodenal bile acids occurred in the youngest infants, and increasing concentrations were found with increasing age. Taurine conjugated bile acids predominated in early infancy, while in older infants bile acids were mainly conjugate...

B ile is a complex mixture of organic and inorganic molecules that is stored in the gallbladder and released into the proximal small intestine when a meal is eaten. Bile is both an excretory secretion, to eliminate cholesterol, bilirubin, and waste products, and a digestive secretion, to promote lipid absorption. The dominant organic constituents of bile are conjugated bile acids (also termed b...