Bacteria and gallstone nucleation

This preliminary study reports for the first time that there might be a possible association between bacteria and the aetiology of some cholesterol calculi. The gall-bladder biles from 225 cholecystectomy patients underwent bacteriological and microscopic study. Cholesterol calculi from 13 patients (10.2%) were observed to be associated with gall-bladder bile profusely infected with at least one bacterial species that was shown to possess beta-glucuronidase activity, an enzyme that is thought to promote calcium bilirubinate precipitation in bile. Concomitantly, the associated gall-bladder bile was 'high' in calcium bilirubinate precipitation and the precipitate was also detected in the centre of the gallstones. Moreover, in approximately half of these patients (six of 13), the cholesterol gallstones' nuclear areas also contained calcium palmitate, which is also thought to be due to bacterial activity. The results also support the hypothesis that bacteria with active beta-glucuronidase (for example, Escherichia coli) can significantly influence the aetiology of brown pigment gallstones. In contrast, bacteria were observed to have no role in black pigment gallstone formation, as their associated gall-bladder biles were always observed to be sterile.

Synthesis of 5 beta-cholestane-3 alpha,6 beta,7 alpha,25,26-pentol and identification of a novel bile alcohol, alpha-trichechol, present in the West Indian manatee bile

In order to confirm the structure of alpha-trichechol, the major bile alcohol of the West Indian manatee, chemical synthesis of 5 beta-cholestane-3 alpha,6 beta,7 alpha,25,26-pentol was carried out. The chain of 3 alpha-hydroxy-5 beta-chol-6-en-24-oic acid was elongated by an Arndt-Eistert reaction to form 3 alpha-hydroxy-26,27-dinor-5 beta-cholest-6-en-25-oic acid. The unsaturated C25 bile acid was converted into 3 alpha,6 beta,7 alpha-trihydroxy-25-homo-5 beta-cholan-25-oic acid by 1,2-glycol formation of the delta 6-double bond. The acetylated derivative of the trihydroxy C25 bile acid was then converted into 3 alpha,6 beta,7 alpha,26-tetraacetoxy-27-nor-5 beta-cholestan-25-one by successive treatment with thionyl chloride, diazomethane, and acetic acid. A Grignard reaction of the 25-oxo compound with methylmagnesium iodide afforded the desired bile alcohol, 5 beta-cholestane-3 alpha,6 beta,7 alpha,25,26-pentol. By direct comparison with the synthetic pentahydroxy bile alcohol, the structure of the naturally occurring alpha-trichechol was determined to be 5 beta-cholestane-3 alpha,6 beta,7 alpha,25,26-pentol.

Quasielastic light scattering evidence for vesicular secretion of biliary lipids

We employed quasielastic light scattering, negative-stain, and freeze-fracture electron microscopy to study the time-dependent physicochemical behavior of biliary lipids in fresh rat bile. Three to five minutes after bile collection, the earliest light scattering measurements and electron microscopy revealed unilamellar vesicles (mean hydrodynamic radius, Rh = 430-740 A) coexisting with mixed micelles (Rh = 20-120 A) in all biles. Both percent biliary vesicles (1 to greater than 70%) and micellar sizes varied inversely with bile salt concentration (range 1.6-72 mM) both during endogenous pool drainage and sodium taurocholate infusion. With bile salt concentrations in the vicinity of or below the estimated critical micellar concentration, biliary vesicle concentrations remained constant or increased slightly with passage of time. However, with micellar bile salt concentrations, complete conversion of vesicles to micelles occurred at rates that were directly proportional to bile salt concentration. Back-extrapolation of weighted Rh averages of micelles plus vesicles as functions of time gave sizes of approximately 470 A at 1 min, suggesting the predominance of homogeneously sized unilamellar vesicles at the earliest stages of bile formation. After micellization of lipids, mixed protein aggregates of vesicle size were demonstrated in all biles. These experiments elucidate the dynamic coexistence of lipid vesicles and mixed micelles in cholesterol unsaturated biles and demonstrate that vesicle-to-micelle interconversions of biliary lipid aggregates are normal physiological phenomena within the biliary tree.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacterial chemotactic oligopeptides and the intestinal mucosal barrier

Intestinal absorption and enterohepatic circulation of N-formyl-methionyl-leucyl-125I-tyrosine, a bioactive synthetic analog of the bacterial chemotactic peptide N-formyl-methionyl-leucyl-phenylalanine has been investigated in the rat. In ileum and proximal and distal colon, dithiothreitol, which increases mucosal permeability, increased peptide absorption and biliary recovery fourfold, 70-fold, and 20-fold over control values, respectively. When dithiothreitol was combined with d-l-benzyl succinate, a potent inhibitor of intestinal carboxypeptidase, absorption and biliary recovery from ileal loops increased markedly to 40-fold over control, whereas there was no further increase in absorption from colon loops. There was a strong correlation between biliary N-formyl-methionyl-leucyl-125I-tyrosine recovery and intestinal absorption of 51Cr-ethylenediaminetetraacetate, a marker of passive mucosal permeability (r = 0.97). We conclude that in the ileum both enzymic degradation and restricted mucosal permeability contribute to the intestinal barrier to luminal bacterial formyl oligopeptides. In the colon, however, enzymic mechanisms are less active and restricted mucosal permeability is the major factor. Abnormalities of the intestinal mucosal barrier to proinflammatory bacterial peptides could play a role in inflammatory disorders of the gut.

[Research on the fundamental factors and conditions of gallstone formation]

The authors applied scanning electron microscope with synchronization of EDAX to detect the ultrastructure of gallbladder mucosa, metallic elements and their oxides, to observe the bacteria of the core of the gallstone; applied cholecystokinin to observe the effects of abnormal gallbladder contraction on stone formation; applied biochemical, immunological criteria to determine the association between liver and gallbladder diseases and gallstone; applied scanning electron microscope to compare the analysis of mechanical structure of gallstone. According to the results of research, the authors conclude: (1) The basic condition of the formation of the gallstone was the disturbance of physiological reaction of "integration" and "homeostasis" of liver-biliary system. (2) The essential factor of the formation of gallstone was the infection of liver-biliary system. (3) The formation of the gallstone structure was caused by changed physical and chemical mechanics of bile. (4) The synchronization treatment of liver-biliary was the principle of preventing and treating gallstone.

Determination of Arduan and its desacetyl metabolites in biological fluids

The authors elaborated a method for the determination of Arduan and its desacetyl metabolites in biological fluids. The method is based on the use of labelled Arduan and on the determination of radioactivity of the parent drug and metabolites separated by ion-pair TLC in the development system of chloroform-dichloromethane-methanol 6 : 2 : 2 (v/v) 3% NaI (w/v).

[Cancer of the colon and cholelithiasis: bile bacteria, composition of the stones and the bile]

Our recent studies have shown a significant association between lithiasic biliary disease and colorectal cancer. This could be due to the existence of risk factors common to both disease or to a cause-effect correlation between them. This latter hypothesis is supported by the observation in gallstone patients of the increase of biliary and fecal concentrations in secondary biliary acids. These could have co-carcinogenic effect on the colon. With a view to singling out further elements which might help us to understand more clearly the possible cause-effect correlation between cholelithiasis and colon cancer, we examined 12 patients affected by both diseases. In these, we evaluated the composition of the gallbladder stones, by means of spectrophotometry and diffractometry. Bile samples were taken from the gallbladder and used to examine the lipidic composition and the cholesterol saturation index according to Carey. In addition bacteriological examinations were carried out. The results were compared with those of 10 patients with cholelithiasis but not cancer, 10 with cancer but not cholelithiasis and 10 with neither. Analysis of the results did not reveal significant differences in gallstone and bile composition between colon cancer patients with concomitant gallstones and control groups. However, in cancer patients with gallstones a higher incidence of bile bacteria (35.7%) was observed than in the other groups. Bile bacteria were observed more frequently in right colon cancer patients who had pigment stones in 75% of the cases. The results seem to evidence peculiarities in patients with a cancer of right colon.(ABSTRACT TRUNCATED AT 250 WORDS)

Polarized light microscopic examination of human bile in the diagnosis of microlithiasis of the gallbladder

Of the 20 cases with biliary colics who had normal OCG and ultrasound, 11 (55%) showed microlithiasis in the form of cholesterol monohydrate crystals and/or calcium bilirubinate granules on polarized light microscopy of the duodenal bile. Microlithiasis was noted in gallbladder bile of all (100%) the cases with proven gallstones but in none of the duodenal bile samples from healthy subjects. This study suggests that polarized microscopy may be a useful method to detect microlithiasis in patients with repeated biliary colics who have normal OCG and ultrasound examination.

High-performance liquid chromatographic determination of ibuprofen, its metabolites and enantiomers in biological fluids

An isocratic high-performance liquid chromatographic method to determine racemic ibuprofen (assay I) and its major metabolites (assay II) in biological fluids (plasma, urine, bile) using a conventional reversed-phase column is described. A third assay using beta-cyclodextrin as stationary phase (Cyclobond I) for the separation of the ibuprofen enantiomers is also described. A wavelength of 220 nm was used to monitor the substances. The sensitivity of the method was 0.1 microgram/ml for all three assays. The method was demonstrated to be suitable for stereoselective pharmacokinetic studies of ibuprofen in humans and animals.

[Drug cholelitholysis and the nucleation time]

Nucleation time (time elapsed until first appearance of cholesterol crystals in incubated bile fluid) and the lithogenic index were measured on 25 patients (aged 45.1 +/- 16.8 years; Broca index 106.7 +/- 4.2%) with radiolucent gallstones, before receiving daily 500 mg chenodeoxycholic acid and ursodeoxycholic acid orally. The nucleation time in the group of nine patients in whom complete lysis was achieved was 4.7 +/- 0.8 days, compared with 15.0 +/- 2.2 days in those with only incomplete lysis (P less than 0.001). There was no statistically significant difference between the two groups as to age, Broca index, lithogenic index and biochemical values. Thus the determination of nucleation time can contribute to distinguishing between responders and nonresponders to oral treatment for dissolving gallstones and may improve the success rate of the method.

[Chemico-experimental data on the principal bile constituents in patients with obstructive jaundice]

Bile samples from patients suffering from cholestasis were tested. Cholesterol, phospholipids, and bile acids (cholic, lithocholic, deoxycholic, chenodeoxycholic) were measured and the methods for the gas-chromatographic determination of cholesterol and major bile acids as well as for the colorimetric determination of phosphorus in phospholipids of human bile are described in extenso. Bile samplings were first carried out on the day the drainage tube was positioned and were repeated every 5 days for four times. Between the first and the last sampling, 1250 mg of phosphatidylcholine was intravenously administered to each patient daily. The aim of the experiment was to evaluate the possible variations in the bile constituents occurring over the specified time.

Biliary bile acids in cholelithiasis and colon cancer

The role of biliary deoxycholate as an endogenous colon carcinogen and the possible association between cholelithiasis and/or cholecystectomy and the subsequent development of large bowel cancer is unclear. This paper describes biliary bile acids analysis performed on 13 patients undergoing cholecystectomy for gall stones, 10 patients undergoing colonic resection for colon cancer, and eight control patients. For all 31 patients the total bile acids concentration was highly variable (8.3 mg/ml-106.5 mg/ml). The median ratio of primary to secondary bile acids was 2.7:1. The biliary bile acid ratios were similar in both control patients (3.7:1) and those with colon cancer (3.1:1), whereas patients with gall stones had significantly higher secondary bile acid levels in their biliary bile (ratio 1.9:1, p = less than 0.05). This result indicates that raised biliary deoxycholate concentrations are not present in patients with colon cancer and are therefore unlikely to be a major predisposing factor in the aetiology of this disease. It is unlikely that cholelithiasis and/or cholecystectomy predispose to the subsequent development of colon tumours.

Glutathione measurement by high-performance liquid chromatography separation and fluorometric detection of the glutathione-orthophthalaldehyde adduct

Glutathione reacts with orthophthalaldehyde to form a stable, highly fluorescent tricyclic derivative which is easily separated and quantitated by high-performance liquid chromatography. Separation of the glutathione adduct is achieved by isocratic elution over a reverse-phase column with 7.5% methanol/92.5% 0.15 M sodium acetate, pH 7.00. The adduct is detected fluorometrically and quantitated by integration of peak area. Detection of 0.1 to 200 pmol glutathione produces a linear response and the recovery of reduced and oxidized glutathione from rat liver homogenate, bile, and plasma is quantitative. The chemical identity of the adduct was confirmed by mass spectrometry.

Pigment vs. cholesterol microlithiasis: comparison of clinical features, bacteriology, stone and gallbladder composition

We compared 16 cases of pigment microlithiasis with 12 cases of cholesterol microlithiasis. In each case we made a spectrophotometric and diffractometric analysis of the composition of the stones, also analysing bile bacteriology, bile lipid composition and cholesterol saturation indices. The two groups were comparable as regards sex, age, symptoms and clinical features. Pigment microcalculi were often asymptomatic (41.7%), but more often associated with bile bacteria (43.7%) or acute pancreatitis (25%). The results were such as to permit us to view cholesterol microlithiasis and pigment microlithiasis as having different pathogenetic and clinical aspects, and thus as being different diseases.

Identification of 3 alpha,4 beta,7 alpha-trihydroxy-5 beta-cholanoic acid in human bile: reflection of a new pathway in bile acid metabolism in humans

The chemical synthesis, nuclear magnetic resonance, and mass spectrometric characteristics of the first C-4 hydroxylated bile acid analogues are described. The data definitively confirm, for the first time, the identity of 3 alpha,4 beta,7 alpha-trihydroxy-5 beta-cholanoic acid in human fetal gallbladder bile. In addition, 3 alpha,4 beta,7 alpha-12 alpha-tetrahydroxy-5 beta-cholanoic was identified in the feces from healthy newborn infants many days after birth, indicating a hepatic origin for C-4 hydroxylation of bile acids. To our knowledge bile acids hydroxylated at the C-4 position of the steroid nucleus have never been previously recognized in any mammalian species. The finding of this novel bile acid which accounts for 5-15% of the total biliary bile acids in early gestation indicates that C-4 hydroxylation is a unique and important metabolic pathway in early human development.

Changes in the concentration and composition of biliary and serum bile acids in the young domestic fowl

1. Concentrations of biliary and serum bile acids, their molecular compositions and serum cholesterol concentrations were determined in chicks at 2, 3, 4 and 6 weeks of age. 2. The concentration of biliary bile acid was maximal at 3 to 4 weeks, decreasing by 6 weeks of age. 3. The serum concentration of bile acid was maximal at three weeks of age. 4. Serum total cholesterol increased from two weeks and was maximal at 6 weeks of age. 5. Chenodeoxycholic acid was the predominant biliary unconjugated bile acid. 6. Tauro-chenodeoxycholic acid and tauro-cholic acid were the dominant molecular species of biliary and serum conjugated bile acid.

[Cholate-forming function of the liver in patients with chronic alcoholism]

The level of bile acids was studied in the bile and feces in 119 patients with chronic alcoholism using thin-layer chromatography. The cholate-forming function of the liver was found to increase in patients with short alcohol anamnesis in chronic alcoholism. With advance of the alcohol anamnesis the number of patients with reduced cholate-forming function of the liver increased.

Metabolism of 2-amino-3-methylimidazo[4,5-f]quinoline in the male rat

The metabolism of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) was studied in the male rat using the radiochemical labels 14C and 3H at positions 2 and 5 of the molecule, respectively. Adult male Fischer 344 rats were administered [2-14C]IQ or [5-3H]IQ by oral gavage at dose levels of 20 or 40 mg/kg body weight. Rats were also given [2-14C]IQ in the diet at a dose level of 300 ppm for 2 days and after administration of unlabelled IQ (300 ppm) in the diet for approximately 6.5 wk for an additional 2 days. In the initial 48 hr following oral administration of 20 or 40 mg [2-14C]IQ/kg body weight, about 40-50% radioactivity was recovered in the urine, and about 30-38% radioactivity was recovered in the faeces. In the initial 72 hr following consumption of [2-14C]IQ (300 ppm) in the diet about 26% radioactivity was recovered in the urine and about 61% radioactivity was recovered in the faeces. Following cannulation of the bile ducts, rats administered a single dose of [2-14C]IQ (40 mg/kg body weight) by oral gavage excreted about 15% of the administered dose in the bile over a period of 2 days. Urine from rats given [2-14C]IQ contained three main polar metabolites that included a glucuronide, a sulphate ester and IQ sulphamate, and a number of less polar metabolites that included IQ, 2-acetylamino-3-methylimidazo[4,5-f]quinoline, 2-aminoimidazo[4,5-f]quinoline and 2-amino-3,6-dihydro-3-methyl-7H-imidazo[4,5-f]quinoline-7-one (7-OH-IQ). Administration of [2-14C]IQ by oral gavage or in the diet gave the same metabolites, but in different amounts. In the faeces of rats given [2-14C] by oral gavage, IQ-sulphamate was the major metabolite in the polar fraction. Non-polar metabolites similar to those found in the urine were also present, but in different amounts. A major, non-polar faecal metabolite, 7-OH-IQ was probably formed as a result of the activity of the intestinal bacterial flora. In rats given a single gavage dose of [2-14C]IQ, excretion of metabolites was higher in the urine and lower in the faeces compared with that in animals fed [2-14C]IQ in the diet. One polar metabolite present in the urine, IQ-sulphamate (39%), was found at considerably higher levels in rats dosed orally with IQ compared with those fed IQ (less than 6%). Thus, IQ is extensively metabolized to give a number of polar and non-polar metabolites, the amounts of which depend, in part, on the mode of dosing.

Cholelithiasis in hamsters: effects of cholic acid and calcium on gallstone formation

Dietary cholic acid (0.1%) and/or calcium (2.6% as calcium carbonate) were added to a semipurified diet containing cholesterol and ethynyl estradiol to determine whether the incidence of pigment and/or cholesterol gallstones would be changed. Male golden Syrian hamsters were fed the experimental diets for 96 days (Group 1, control; Group 3, cholic acid plus calcium) or only an average of 60 days (Group 2, 0.1% cholic acid). Animals in Group 2 became ill (weight loss, low food intake, diarrhea) possibly due to cholic acid (or deoxycholic acid) toxicity. Cholesterol gallstones and crystals were absent in all experimental groups. The incidence of pigment gallstones was: control, Group 1, 12/16; 0.1% cholic acid, Group 2, 3/13; and 0.1% cholic acid plus calcium, Group 3, 11/22. Cholic acid with or without calcium produced an elevation of both liver and plasma cholesterol: Group 2, 80.1 mg/g and 501 mg/dl; Group 3, 103.7 mg/g and 475 mg/dl vs Group 1, 65 mg/g and 209 mg/dl, respectively. The lithogenic indices of the bile were lower in Groups 2 and 3 compared to Group 1, controls, 0.45 and 0.58 vs 1.16, respectively. The extent of the portal tract pathology could not be correlated with the presence or absence of pigment gallstones or with the levels of lithocholic acid in the hamster bile. In summary, when semipurified diets were supplemented with ethynyl estradiol and cholic acid, with and without calcium supplementation, no cholesterol gallstones formed and the incidence of pigment gallstones was not altered.

Automated pre-column high-performance liquid chromatographic method for the investigation of adibendan metabolism

An automated pre-column high-performance liquid chromatographic method has been developed for the isolation of adibendan and metabolites from biological fluids and for their simultaneous quantitative assay. High sensitivities were obtained by the use of a multiple-injection device allowing solid-phase extraction from several successive sample injections with enrichment of metabolite traces on the pre-column. Two metabolites in dog urine were identified as N-oxypyridine (M1) and 2-hydroxypyridine (M2) derivatives of adibendan, while the structure of M3 is still unknown. M1 and M2 are also metabolites in rats, rabbits and humans, and contribute to cardiovascular efficacy. The metabolic profiles were determined in plasma, urine and bile, as a function of dose, route of administration and sex, using radioactivity and ultraviolet detection of the eluates.

Enhancement of tetrathiomolybdate-induced copper excretion in bile of sheep by the alpha 2-agonistic action of xylazine

The effect of intravenous doses of cortisol and xylazine on the quantity of copper excreted in response to 100 and 200 mg doses of tetrathiomolybdate (TTM) was studied in seven sheep. Cortisol alone produced a non-significant 1.4-fold increase and had no enhancing action on the response to TTM. Xylazine produced a significant 2.25-fold increase, doubled the quantity of copper excreted in response to both doses of TTM and reduced bile flow by approximately 35 per cent. The alpha 2 antagonist, idazoxan, prevented both the latter effects showing that they were due to xylazine's alpha 2-agonistic action. It is suggested that the combination of an alpha 2-agonist with the intravenous injection of TTM in the treatment of acute copper toxicity in sheep could reduced by 50 per cent the amount of molybdenum needed.

[Disruption of the electrolyte and microelement composition of gastric juice and bile in patients with chronic diseases of the hepatobiliary system]

A study is presented of 403 patients with chronic diseases of the stomach and biliary tract. It was established that these patients showed disorders of the electrolytic and micro-element composition of the gastric juice and bile depending on the functional state of the stomach and liver.