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The aim was to study the pharmacokinetic equivalence of the local anaesthetic ropivacaine and its stable isotope analogue [2H3]-ropivacaine. Ropivacaine (40.0–53.0 mg) and [2H3]-ropivacaine (41.9–52.4 mg) were given simultaneously to eight healthy subjects as a single i.v. infusion. Blood and urine samples were collected and the concentrations of ropivacaine and [2H3]-ropivacaine were determined by gas chromatography–mass spectrometry (GC–MS) combined with an isotope dilution technique. The between-days accuracy was about 100% for both compounds and the between-days precisions were 3–13% and 5–11% for ropivacaine and [2H3]-ropivacaine, respectively. The plasma concentrations at the end of the infusion were similar for both forms (about 1 mg l−1), as were clearance (about 475 ml min−1), volume of distribution at steady state (about 54 l) and terminal half-life (about 1.8 h). The 95% confidence intervals for the ratios (ropivacaine/[2H3]-ropivacaine) of the individual parameters were in the range 0.90–1.10. It was concluded that ropivacaine and [2H3]-ropivacaine are pharmacokinetically equivalent.

We have compared the incidence of CNS symptoms and changes in echocardiography and electrophysiology during i.v. infusions of ropivacaine, bupivacaine and placebo. Acute tolerance of i.v. infusion of 10 mg min-1 was studied in a crossover, randomized, double-blind study in 12 volunteers previously acquainted with the CNS effects of lignocaine. The maximum tolerated dose for CNS symptoms was higher after ropivacaine in nine of 12 subjects and higher after bupivacaine in three subjects. The 95% confidence limits for the difference in mean dose between ropivacaine and bupivacaine were -30 and 7 mg. The maximum tolerated unbound arterial plasma concentration was twice as high after ropivacaine (P0.001). Muscular twitching occurred more frequently after bupivacaine (P0.05). The time to disappearance of all symptoms was shorter after ropivacaine (P0.05). A threshold for CNS toxicity was apparent at a mean free plasma concentration of approximately 0.6 mg litre-1 for ropivacaine and 0.3 mg litre-1 for bupivacaine. Bupivacaine increased QRS width during sinus rhythm compared with placebo (P0.001) and ropivacaine (P0.01). Bupivacaine reduced both left ventricular systolic and diastolic function compared with placebo (P0.05 and P0.01, respectively), while ropivacaine reduced only systolic function (P0.01).

Background The aim was to characterize ropivacaine and 2′,6′-pipecoloxylidide (PPX) pharmacokinetics and factors affecting them in paediatric anaesthesia. Methods Population pharmacokinetics of ropivacaine and its active metabolite PPX were estimated after single and continuous ropivacaine blocks in 192 patients aged 0–12 yr from six pooled published studies. Unbound and total ropivacaine and PPX plasma concentration and PPX urinary excretion data were used for non-linear mixed-effects modelling by NONMEM. Covariates included age, body weight, gender, ethnic origin, ASA, site and method of administration, and total dose. Results One-compartment first-order pharmacokinetic models incorporating linear binding of ropivacaine and PPX to α1-acid glycoprotein were used. After accounting for the effect of body weight, clearance of unbound ropivacaine and PPX reached 41% and 89% of their mature values, respectively, at the age of 6 months. Ropivacaine half-life decreased with age from 13 h in the newborn to 3 h beyond 1 yr. PPX half-life differed from 19 h in the newborn to 8–11 h between 1 and 12 months to 17 h after 1 yr. Simulations indicate that for a single caudal block, the recommended dose could be increased by a factor of 2.9 (0–1 month group) and 6.3 (1–12 yr group) before the unbound plasma concentrations would cross the threshold for systemic toxicity. Corresponding factors for continuous epidural infusion are 1.8 and 4.9. Conclusions Ropivacaine and PPX unbound clearance depends on body weight and age. The results support approved dose recommendations of ropivacaine for the paediatric population.

Specialised gastrointestinal absorption of amoxicillin has been suggested in man and has been demonstrated in animals. In order to study the rate and extent of amoxicillin absorption, six healthy subjects were given 500 mg IV and two oral doses (500 mg and 3 g as a suspension). Absorption kinetics was analysed by compartmental modelling, noncompartmental methods and by calculation of absorption rates using deconvolution. Dose-dependency of the extent of amoxicillin absorption was observed, with a lower than expected mean maximum plasma concentration (49%), and fraction of the dose absorbed (39%) after the 3 g dose calculated from the 500 mg dose, assuming kinetic linearity. Zero-order kinetics of absorption was apparent in some subjects after the 500 mg dose, both from model fitting and absorption rate profile. However, no pattern consistent with pure first-order or zero-order absorption was observed after both oral doses in any individual. The dose-dependency of amoxicillin absorption was confirmed by a trend to an increased time of absorption for the high dose. The results show the variable nature and nonlinearity of the gastrointestinal absorption of amoxicillin and indicate the involvement of a number of factors, in addition to simple diffusion.

A proposal is made for a system of nomenclature of the more common unconjugated and conjugated bile acids. Acceptable trivial names for bile acids are tabulated, and guidelines are proposed for using these existing trivial names as roots to create acceptable semi-systematic names for other bile acids, as well as for new natural bile acids that will be discovered in the future. The term alpha-hyocholic is recommended to replace hyocholic, and beta-hyocholic to replace omega-muricholic. The term murideoxycholic acid is recommended for 3 alpha,6 beta-dihydroxy-5 beta-cholan-24-oic acid. Proposals are also made for bile acids with epimeric hydroxy groups, for unsaturated bile acids, and for bile acids with oxo- and/or hydroxy-oxo- substituents on the nucleus and/or on the side chain. For conjugated bile acids, the term "aminoacyl amidates" is recommended to replace "amidates" for bile acids conjugated in N-acyl linkage with amino acids. Nomenclature for other types of conjugates (sulfates, glucuronides, glucosides) is included as well as abbreviations. It is recommended that the historic tradition of naming a newly discovered bile acid after the species from which it was isolated be abandoned, and that in the future such a bile acid should be named using the principles contained in this paper.

Our previous method for analysis of organochlorine contaminants in human milk was modified and adapted to analysis of non-ortho coplanar polychlorinated biphenyls (PCBs). The total levels of PCBs and the concentrations of certain congeners were determined in human milk sampled in 1972 – 1989. The levels of the congeners decreased during the time period studied in accordance with previous investigations of total PCBs. Among the non-ortho coplanar PCBs the most toxic congener, 3,3′,4,4′,5-pentachlorobiphenyl (IUPAC No. 126), was the most abundant. This compound was present at levels about 50 times higher than those of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and it may therefore be considered a more harmful contaminant in human milk than TCDD.

The efficacy of ropivacaine 100 mg (5 mg ml(-1)), 150 mg (7.5 mg ml(-1)) and 200 mg (10 mg ml(-1)) and bupivacaine 100 mg (5 mg ml(-1)) given by intra-articular injection into the knee after the end of surgery was studied in 72 ASA I-II patients scheduled for elective knee arthroscopy under general anaesthesia in a randomized, double-blind study. Kapake (paracetamol 1 g and codeine 60 mg) was given as a supplementary analgesic. Pain scores were assessed 1-4 h after surgery and a verbal rating scale of overall pain severity was assessed on second postoperative day. Ropivacaine or bupivacaine concentrations were determined in peripheral venous plasma up to 3 h after injection in eight patients in each group. Verbal rating pain scores were lower with ropivacaine 150 mg compared with bupivacaine 100 mg (P

Collision-induced dissociation (CID) mass spectra were recorded on underivatized, hydroxylated lipoxygenase products, including S(S)-, 12(S)- and 15(S)-hydroxyeicosatetraenoic adds (HETE), leukotriene (LT) B4, LTB5, the LTB4 metabolites 20-OH-LTB4, 20-COOH-LTB4 and 10,11-dihydro-LTB4, the LTB4 isomers 6-trans-LTB4, 6-trans,12-epi-LTB4 and S(S),12(S)-dihydroxyeicosatetraenoic acid (diHETE) as well as S(S),6(R)-diHETE, 14(S), 15(R)-diHETE and lipoxin (LX) A4 and B4. Pseudomolecular [M-H]- parent ions were generated by electrospray ionization. The ions were accelerated to 4 keV, selected by the double focusing sectors Of 2 hybrid tandem mass spectrometer, decelerated to 400 eV and focused into a collision cell containing xenon. The resulting fragment ions were mass analysed by an orthogonal time-of-flight analyser. The CID spectra obtained were structurally informative allowing isomer differentiation.

A total of 100 nonobese and normolipidemic subjects (29 control subjects, 49 patients with cholesterol stones [CSs], and 22 patients with brown pigment stones) were studied to elucidate the pathogenetic contributions of deoxycholate (DC) to supersaturated bile formation with special reference to de novo syntheses of cholesterol and bile acids in the liver. A higher proportion of DC was observed in gallbladder bile from patients with CSs (CSs; 21.7 +/- 1.4%, mean +/- SEM, vs. control subjects; 10.2 +/- 0.9%). Cholesterol saturation in bile was elevated parallel to the increase of DC (r = .48; P = .0002), irrespective of the existence of stones. In a comparison between the 52 subjects with increased DC in bile (10% of biliary bile acids) and the 20 subjects without the increase (10%), the molar percentage of cholesterol in bile was significantly higher in the former (9.4 +/- 0.5%) than in the latter (6.7 +/- 0.4%) (P.001). Consistent with the decrease in steady-state level of low-density lipoprotein (LDL) receptor-messenger RNA (mRNA), the catalytic activity and mRNA level of microsomal hepatic 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, the rate-limiting enzyme for de novo cholesterol synthesis, were significantly lower in the former (2.9 +/- 0.3 pmol/min/mg protein) than in the latter (5.1 +/- 0.6) (P.0001). Biliary molar percentage of bile acids was significantly lower in the former (69.8 +/- 1.1%) than in the latter (75.2 +/- 1.5%) (P.01). However, contrary to expectations, the catalytic activity and mRNA level of cholesterol 7 alpha-hydroxylase, the rate-limiting enzyme for bile acid synthesis, were significantly higher in the former (5.8 +/- 0.4 pmol/min/mg protein) than in the latter (3.7 +/- 0.6) (P.01). The magnitude of the impaired gallbladder emptying (control subjects; 78.4 +/- 4% vs. CSs; 58 +/- 3%; P.0005) together with the prolonged small intestinal transit (control subjects; 126 +/- 9 minutes vs. CSs; 198 +/- 9 minutes; P.01) correlated significantly with the increased percentage of DC in bile. It is concluded that in cholesterol gallstone disease an increase of DC in bile, linked to an impaired gallbladder emptying together with a prolonged small intestinal transit, may play a significant role in downregulating de novo cholesterol synthesis but not bile acid synthesis in the liver.(ABSTRACT TRUNCATED AT 400 WORDS)

27-hydroxycholesterol is shown to be 7 alpha-hydroxylated by microsomal preparations of rat brain. The apparent Km was about 2 microM and Vmax about 15 pmol/min x mg protein. The reaction might modulate biological functions of 27-hydroxycholesterol, such as its suppressive effect on the activity of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, and supports the possibility of bile acid formation in the brain.

Fast atom bombardment mass spectrometry was used as a detection method in a study of the extraction of urinary bile acids with octadecylsilane-bonded silica. The procedure commonly used in many laboratories was found to result in significant losses of sulfated taurine-conjugated bile acids. Losses of other double conjugates and of bile acid and bile alcohol glucuronides were also seen. The losses were avoided by addition of an equal volume of 0.5 M triethylamine sulfate to the urine before passing it through the sorbent bed. Quantitative elution was then achieved with methanol. Batch variations were observed with sorbents from two different manufacturers.

In order to establish the position of conjugation of bile acids with glucose or N-acetylglucosamine, glucosides of chenodeoxycholic and hyodeoxycholic acids and of 13C-labeled cholic, lithocholic, chenodeoxycholic, hyodeoxycholic, and ursodeoxycholic acids, and N-acetylglucosaminides of ursodeoxycholic, isoursodeoxycholic, 3-dehydro-ursodeoxycholic, and ursodeoxycholylglycine were synthesized in vitro. The conjugates were purified by anion-exchange chromatography and reversed-phase HLPC and were analyzed by gas chromatography-mass spectrometry. The glucosides of chenodeoxycholic and hyodeoxycholic acids were also analyzed after periodate and chronic acid oxidation. All conjugates were analyzed by fast atom bombardment mass spectrometry with collision-induced dissociation. Glucose conjugation was shown to occur at C-3 in all bile acid glucosides studied. In contrast, the selective N-acetylglucosaminidation of 7 beta-hydroxy bile acids was shown to occur at the 7 beta-position.

A RIA procedure for measuring progesterone (PROG), 5 alpha-pregnane-3,20-dione (5 alpha-DH PROG), and 3 alpha-hydroxy-5 alpha-pregnan-20-one (3 alpha,5 alpha-TH PROG) has been developed and validated by GLC/mass spectrometry. Measurements were made in intact and adrenalectomized (ADX) male rats, in cyclic, pregnant, spayed, and spayed-ADX females, and in both males and spayed females injected with PROG. The predominant contribution of the ovary to the concentrations of 3 alpha,5 alpha-TH PROG in plasma and brain, was indicated by its larger levels in females, in particular during pregnancy, and by its presence in ovarian tissue and disappearance after ovariectomy. An additional adrenal origin in both males and females was shown. Neither PROG nor 5 alpha-DH PROG disappeared from brain, contrary to plasma, after combined adrenalectomy and gonadectomy, thus suggesting that PROG might be synthetized de novo in brain. However, the concentrations of 3 alpha,5 alpha-TH PROG in plasma and brain of female rats were positively correlated with the concentrations of PROG in plasma, indicating that plasma PROG was the major precursor of 3 alpha,5 alpha-TH PROG. The direct formation of 3 alpha,5 alpha-TH PROG from PROG in brain was strongly suggested by the increased 3 alpha,5 alpha-TH PROG/PROG ratios in brain vs. plasma, when measured in control females, and after injection of PROG to both males and OVX females. It was previously reported that 3 alpha,5 alpha-TH PROG is a sedative/anxiolytic steroid, as a result of its binding to gamma-aminobutyric acid (GABA)A receptors and allosteric potentiation of GABAcergic neurotransmission. Its concentrations in brain reach indeed the neuroactive range in cyclic and pregnant females, and are compatible with a physiological role of this neurosteroid.

Using a novel combination of analytical chemical and molecular biological techniques, lipophilic components of human plasma separated according to their physico-chemical properties were screened for their ability to activate the rat peroxisome proliferator-activated receptor (rPPAR). Activation of an rPPAR/glucocorticoid receptor chimera stably expressed in CHO cells by fractions in the initial screening guided further subfractionation. Characterization of an active subfraction by gas chromatography alone and in combination with mass spectrometry (GC-MS), indicated the presence of free fatty acids. Individual active components in this mixture were isolated by a final fractionation using high performance liquid chromatography (HPLC). GC-MS analyses of HPLC fractions able to activate the chimeric receptor identified palmitic acid, oleic acid, linoleic acid, and arachidonic acid as endogenous activators of rPPAR. No other activators were identified. This approach is able to specifically extract and identify endogenous activators of PPAR from a complex biological extract and as such may be valuable in the identification of activators of other orphan receptors in the steroid hormone receptor superfamily.

In a search for enzymes involved in the formation of bile acids from 27-hydroxycholesterol in humans, the metabolism of this and other side-chain oxygenated steroids was studied in human liver microsomes and mitochondria. The microsomal fraction contained enzyme(s) catalyzing 7 alpha-hydroxylation of 27-hydroxycholesterol and 3 beta-hydroxy-5-cholestenoic acid, whereas the 7 alpha-hydroxylation of cholesterol and 3 beta-hydroxy-5-cholenoic acid was low. Only small amounts of 7 beta-hydroxylated products were formed. Purification and subfractionation of microsomal protein yielded a fraction of cytochrome P-450, which required NADPH and NADPH-cytochrome P-450 reductase and catalyzed 7 alpha-hydroxylation of the side-chain oxygenated 3 beta-hydroxy-delta 5-C27-steroids but was inactive toward cholesterol. Added cholesterol did not inhibit the observed enzymatic activity. The results provide evidence that this enzyme is different from cholesterol 7 alpha-hydroxylase. The mitochondrial fraction contained enzyme(s) that catalyzed an isocitrate-dependent 7 alpha-hydroxylation of 3 beta-hydroxy-5-cholestenoic acid. The activity was much lower with 27-hydroxycholesterol. The mitochondrial fraction also catalyzed the oxidation of the 27-hydroxy group and contained a 3 beta-hydroxy-delta 5-steroid dehydrogenase active on 7 alpha-hydroxylated C27-steroids. The metabolic end product of the reactions catalyzed by these enzymes was 7 alpha-hydroxy-3-oxo-4-cholestenoic acid. A considerable fraction of the 7 alpha-hydroxy-delta 5 intermediates was also converted to the corresponding 7 beta-hydroxysteroids, probably by way of the 7-oxosteroids, suggesting the presence of an epimerizing enzyme in the mitochondrial fraction.

Hydrophobic peptides were isolated from the phospholipid fraction of human bile, plasma and spleen by exclusion chromatography in organic solvents. From plasma, the activation peptide of C1 protease inhibitor was recovered, from spleen the activation peptide of alpha 1-antitrypsin, and from bile, both these peptides, as well as a fragment generated by proteolytic cleavage of alpha 1-antitrypsin six residues N-terminal of the P1-P1' peptide bond. Cleavages in this region inactivate antiproteases but have previously not been reported to occur in vivo. These peptides in human bile may reflect physiological actions in regulation of antiproteolytic activity or bile secretion processes, and/or be of importance for the physicochemical state of cholesterol, phospholipids and bile acids in bile.

Amoxicillin was given as single doses of 375, 700, 1500, 3000 and 6000 mg an oral suspension to four volunteers with an ileostomy and with no active intestinal disease after an overnight fast. The excretion of amoxicillin and its penicilloic acid was followed in samples taken from the ileostomy and in urine produced over 6 h. Beta-lactamase activity was measured in ileal fluid and none was found. The percentage of the dose recovered from the ileostomy increased successively from 8% at the lowest dose to 77% at the highest dose. A complementary excretion pattern of amoxicillin was found in the urine, amounting to 70% recovery at the lowest dose to 23% at the highest dose. The results confirm the dose-dependence of the absorption of amoxicillin, which could at least in part be due to specialised absorption of this drug in humans.

Duodenal bile, urine, plasma, and feces from a child with hepatic 3 beta-hydroxy-delta 5-C27-steroid dehydrogenase deficiency were analyzed by fast atom bombardment mass spectrometry and gas chromatography-mass spectrometry to investigate the formation and excretion of abnormal bile acids and bile alcohols. The biliary bile salts consisted of glycocholic acid (25%) and of sulfated and glycine conjugated di- and trihydroxycholenoic acids (55%), two C27 bile acids, and eleven sulfated bile alcohols (mainly tetrols, 20%), all having 3 beta,7 alpha-dihydroxy-delta 5 or 3 beta,7 alpha,12 alpha-trihydroxy-delta 5 ring structures. In plasma, sulfated cholenoic acids constituted 65% and unconjugated 3 beta,7 alpha-dihydroxy-5-cholestenoic acid 25% of the total level, 71 micrograms/ml. The urinary excretion of the former was 30.4 mg/day and that of unsaturated bile alcohol sulfates, mainly pentols, 7 mg/day. The predominant bile acid in feces was an unconjugated epimer of 3 beta,7 alpha,12 alpha-trihydroxy-5-cholenoic acid, and small amounts of cholic acid were present. The minimum total excretion was 11.3 mg/day. Treatment with chenodeoxycholic acid resulted in marked clinical improvement and normalized liver function tests. Further studies are needed to define the mechanism of action. Plasma bile acids decreased to 1.6 micrograms/ml and urinary excretion to 3.4 mg/day. Chenodeoxycholic and ursodeoxycholic acids became predominant in all samples. The fecal excretion of unsaturated cholenoic acid sulfates increased to 40 mg/day compared to 89 mg/day of saturated bile acids. The results provide further support for a defective hepatic 3 beta-hydroxy-delta 5-C27-steroid dehydrogenase deficiency, and indicate that the 3 beta-hydroxy-delta 5 bile acids are formed via 7 alpha-hydroxycholesterol. The formation of glycocholic acid may be due to an incomplete enzyme defect or to transformation of the 3 beta-hydroxy-delta 5 structure by bacterial and hepatic enzymes during an enterohepatic circulation.

Eubacterium species V.P.I. 12708 has inducible bile acid 7-dehydroxylase activity that can use either 7 alpha or 7 beta bile acids as substrates. Cell extracts prepared from bacteria grown in the presence of cholic acid catalyzed the rapid conversion of free bile acids into a highly polar bile acid metabolite (HPBA). This conjugation activity co-eluted with bile acid 7-dehydroxylase activity on high performance gel filtration chromatography (GFC). The HPBA was purified by a combination of high performance GFC and reverse-phase high performance liquid chromatography (HPLC). The intact HPBA eluted earlier from reverse-phase HPLC than deoxycholyl-CoA and had a Mr of 1102 by Bio-Gel P-2 (GFC). The HPBA had an absorption peak at 255 nm and was sensitive to treatment with phosphodiesterase I or nucleotide pyrophosphatase. The HPBA has a free phosphate as shown by an increase in elution volume on reverse-phase HPLC following treatment with alkaline phosphatase. Treatment of the purified HPBA with nucleotide pyrophosphate plus alkaline phosphatase yielded adenosine, whereas, treatment with nucleotide pyrophosphatase alone generated 5',3'-ADP. A bile acid metabolite was also generated by nucleotide pyrophosphatase treatment. The bile acid metabolite had different chromatographic properties (HPLC and TLC) than the corresponding free bile acid. Gas liquid chromatography-mass spectrometry showed the bile acid metabolite to be 12 alpha-hydroxy-3-oxo-4-cholenoic acid. We hypothesize that the HPBA is an intermediate in 7-dehydroxylation and consists of this compound linked at the C-24 with an anhydride bond to the beta phosphate (5') of ADP-3'-phosphate. These results suggest a novel mechanism of bile acid 7 alpha/7 beta-dehydroxylation in Eubacterium sp. V.P.I. 12708.

Unconjugated steroids of low and medium polarity can be essentially quantitatively extracted from aqueous solutions by rapid filtration through a small column of Lipidex 1000. Forty ml of urine can be extracted by a 4 ml column bed at a flow rate of 5 ml/ min. Less polar steroids (progesterone, testosterone) can be extracted directly, whereas 5% pentylamine has to be added to the aqueous solution to give a quantitative extraction of cortisol. The same method can be used for extraction of steroids in plasma. It is suggested that this method may be generally applicable to the extraction from biological fluids of compounds with a polarity similar to or lower than that of steroids.

The bile acid composition in duodenal bile was analysed in 22 diet-treated and 11 insulin-treated middle-aged patients with diabetes mellitus and in 20 normoglycaemic controls. In 10 subjects with diabetes mellitus the bile acid profile in urine was also investigated. In the non-insulin-dependent diabetic patients the percentage of cholic acid was reduced and that of deoxycholic acid increased. As a highly significant finding there was a three-fold increase of the percentage of 12-ketolithocholic acid in duodenal bile in non-insulin-dependent diabetics, whereas the bile acid composition in insulin-dependent diabetics was similar to that in a control group. The percentage of 12-ketolithocholic acid in duodenal bile was positively correlated to the percentage in urine. In nine of the subjects studied, 12-ketolithocholic acid was the major individual bile acid in urine. It constituted 36.3 +/- 4.4% of the bile acids analysed and the excretion was 6.1 +/- 2.3 mumol 24 h-1. Together with 3 alpha, 12 beta-dihydroxy-5 beta-cholanoic acid it was predominantly present in the glycine conjugate fraction, whereas in bile its conjugation was similar to that of the other bile acids. The results may reflect an increased formation of secondary bile acids from cholic acid combined with a metabolic disturbance in non-insulin-dependent diabetics affecting the oxidoreduction of bile acids at C-12.

The metabolism of 14C-labeled chenodeoxycholic, cholic, and deoxycholic acids was studied in patients with intrahepatic cholestasis. Radioactively labeled metabolites were isolated from urine and were identified by gas-liquid chromatography-mass spectrometry. About 5% of the radioactivity was recovered in urine after administration of labeled chenodeoxycholic acid to a patient with mild intrahepatic cholestasis. In urine collected 0-24 hr after the injection, 20% of the radioactivity appeared in the combined glycine and taurine conjugate fractions, and the predominant metabolite in these fractions was identified as hyocholic acid. Eighty percent of the activity was eluted in the sulfate fraction presumably representing mainly sulfated chenodeoxycholic acid conjugates. Twenty percent of the radioactivity was recovered in urine following administration of labeled cholic acid to a patient with biliary cirrhosis and severe cholestasis. In urine collected on the fifth day, half of this radioactivity appeared in the glycine and taurine conjugate fractions, and 10% of this activity was present as tetrahydroxycholanoates. The major metabolites in this fraction were 3 alpha, 6 alpha, 7 alpha, 12 alpha-tetrahydroxy-5 beta- and 1 xi, 3 alpha, 7 alpha, 12 alpha-tetrahydroxy-5 beta-cholanoic acids. The former compound constituted about 50% of the tetrahydroxycholanoates. Three additional minor tetrahydroxy bile acids were present, one of which was tentatively identified as 6 beta-hydroxycholic acid. About 5% of the radioactivity appeared in urine after oral administration of labeled deoxycholic acid to a patient with mild intrahepatic cholestasis. Twenty-two percent of the activity appeared in the glycine and taurine conjugate fractions isolated from urine collected on the second day after the administration. About 75% of this activity was associated with trihydroxycholanoates. The main metabolite was 1 beta-hydroxydeoxycholic acid with small amounts of, tentatively, 6 alpha-hydroxydeoxycholic acid.

In an open multicentre study of bacampicillin (Penglobe®), a new orally well absorbed prodrug of ampicillin, 516 patients with acute exacerbations of chronic bronchitis or pneumonia were treated by a group of Belgian pneumologists or internists. Bacampicillin was given in a dosage regimen of 400 mg or 800 mg three times daily. In patients with acute exacerbations of chronic bronchitis the clinical success rate was high, over 95% in both groups. A n improvement in the sputum purulence score was seen in 93% of the patients with an initially purulent sputum and 69% had a normal mucoid sputum at follow-up. The clinical success rate in patients with pneumonia was also similar in both dosage groups with success rates over 96%. The total number of patients with adverse reactions was not more than 5·4%, of which the majority were considered mild or moderate. Each type of side-effect occurred in a frequency of 1·2% or less. There were no differences between the two dosage regimens as regards the frequency of side-effects which indicates a remarkably good tolerance of bacampicillin also with the higher dosage.

Antibody responses to the penicilloyl moiety were recorded in patients treated intramuscularly with ámpicillin for respiratory infections. For practical reasons this was performed at two clinics. At each clinic, two commercially available ampicillin preparations were used in a single-blind, randomised study. One of the preparations at each clinic was of high-grade purity and the other was slightly contaminated, according to a radioimmunoassay. There was the same heterogeneity in the patient material between the two clinics. The results showed a slight but significant (p < 0.001) increase in IgM penicilloyl antibodies in the group of patients treated with the pure penicillin but not in those treated with the contaminated penicillin. When the patients in the two studies were analysed jointly, the increase in IgM antibodies was significantly greater (p < 0.05) in the group treated with pure penicillin than in that treated with impure penicillin. The difference in antibody formation between the patient groups treated with pure or contamined ampicillin at each clinic was not significant, however. An immunological activity of the impurities suppressing; the IgM antibody response is suggested.

Antibody responses to penicilloyl were recorded in infants and children treated for about 1 week with intravenous ampicillin. In this single-blind, randomized study two commercially available preparations were compared, one of high-grade purity (less than 0.1 microgram antigen per gram) and the other slightly contaminated with high molecular weight proteinaceous material (1.5 microgram antigen per gram) according to a radioimmunoassay. The results showed no significant increase in the antibody titers in any of the patient groups. The immunogenic properties of high molecular weight proteinaceous impurities isolated from phenoxymethyl penicillin during manufacture were tested in rabbits given daily subcutaneous injections with 0.1-10 micrograms of the antigen over 10 day periods. When the 10-day period was repeated, the rabbits injected with more than 2 micrograms of antigen responded with both IgM/IgG and IgE antibodies. The clinical as well as the animal study indicates that antigen impurities in the preparations of the order of 2 micrograms per gram or less do not elicit a significant antibody response. However, the study in rabbits demonstrates that high molecular weight impurities can induce penicillin allergy if present in about 10-fold higher quantities than those usually found in the commercial penicillin preparations of today.

Bile acids in bile from male and female rats with cannulated bile ducts have been analyzed by repetitive scanning gas–liquid chromatography–mass spectrometry after initial fractionation of conjugate classes on diethylaminohydroxypropyl Sephadex LH-20. Sex differences were observed in the amounts and types of bile acids in the sulfate fraction. The proportion of total bile acids excreted as sulfates was higher in female (0.9–1.3%) than in male (0.1–0.2%) rats. Most of the sulfated bile acids had a 5α configuration, allochenodeoxycholic acid being the major compound in bile from female rats. This bile acid was also present in the nonsulfate fraction but could not be found in bile from male rats. The results indicate that gas–liquid chromatography–mass spectrometry has to be used to provide sufficient specificity in the bile acid analyses. Thus, compounds from the sulfate fraction having the retention times of cholic and chenodeoxycholic acid derivatives were found to be due to derivatives of the 3β,5α-isomers of these bile acids.

The effects of ethynylestradiol on endogenous bile acids, their capacity to conjugate and excrete intravenously infused cholic acid, the concentrations of biliary cholesterol and lecithin, and the individual molecular species of phosphatidylcholine have been determined in male and female Sprague–Dawley rats. Endogenous biliary bile acids were analyzed by gas–liquid chromatography–mass spectrometry. Eleven bile acids were identified and several minor bile acids, primarily muricholates, could not be completely characterized. After 5 days of treatment with ethynylestradiol (1 mg/kg per day), the percentage of cholic acid decreased and the percentage of 6β-hydroxylated bile acids, including several monounsaturated species, increased. Ethynylestradiol caused a decrease in bile acid-independent bile flow. Intravenous infusion of cholic acid at a high concentration caused cholestasis in control animals but, after ethynylestradiol treatment, cholestasis developed during the infusion of a much lower concentration of cholate, indicating a lowered threshhold for bile acid-induced cholestasis. In the treated rats, there was a slight increase in excretion of unconjugated endogenous bile acids, and a striking impairment of conjugation of intravenously administered cholic acid. One of the few sex-related differences observed was an increased concentration of biliary phospholipids in untreated male rats. Both phospholipid and cholesterol concentrations in the bile were higher in the treated animals. The molar percentage of cholesterol was always 1–2%, but it was slightly higher in treated animals, especially males. Ethynylestradiol treatment also affected biliary phospholipid by causing a marked increase of phosphatidylcholine species containing palmitic and oleic acid residues and a decrease of species containing stearic and linoleic acid residues. There was no increase in biliary excretion of long chain polyunsaturated species, which might have indicated damage to membranes, in response to ethynylestradiol either alone or with cholic acid infusion. Some of these ethynylestradiol-induced changes in biliary bile acid and lipid excretion are probably peculiar to the rat, but others, such as the increase in molar percentage of cholesterol and cholestasis, may be relevant to disorders in man, especially cholesterol gallstones and idiopathic cholestasis of pregnancy.

The aim of the study was to evaluate two essentially different methods of assessing differences in children's taste preferences with regard to five different paediatric penicillin formulations. The study was performed with a parallel group design comparing five groups. A taste evaluation was recorded in 103 children with upper respiratory tract infections after a single therapeutic test dose. First the patient's own spontaneous verbal judgement was recorded then a judgement was arrived at using a hedonic scale of facial expressions. Both judgements were passed immediately and also 3-4 minutes after the test dose. In the children who were 6 years of age or younger, a better discrimination of taste differences between formulations was achieved by using the patients' own spontaneous verbal judgements instead of the facial hedonic method. Both methods seem appropriate in older children, but the hedonic scale is preferable since its use implies a more standardised procedure.

Summary. The intestinal absorption of cholanic acid-24-14C in rats has been studied. In the normal rat about 70 per cent of an administered amount is absorbed. In the rats with lymph fistulas 3–7 per cent of the activity was found in the lymph. The amount of cholanic acid absorbed in rats having both a bile duct and a lymph duct fistula was less than in normal rats. About 10 per cent of the absorbed activity was flounce in the lymph, 90 per cent was excreted in the bile. Factors governing the route of transport after intestinal absorption of fatty acids have been discussed.

Tritium-labelled cholic acid was given to four rats and radioactive bile acids in the portal blood were analyzed with reversed phase partition chromatography after two days. One tenth to two tenths per cent of the radioactivity mixed with the bile acid pool was present in one ml of portal blood. About 15 per cent of the radioactive portal bile acids were unconjugated, approximately 50 per cent of which was deoxycholic acid as judged by its chromatographic behaviour. These figures have been used for rough calculations of the extent of enterohepatic circulation and cecal absorption of cholic acid and its metabolites, and for the estimation of the daily conversion of cholic acid into deoxycholie acid by intestinal microorganisms.

This is a report of a 28-year-old woman with cholestasis occurring in the first month of gestation in four consecutive pregnancies. During the interval between the third and fourth pregnancy as well as during and after the fourth one the patient was regularly examined with regard to her liver function. Intensive itching and markedly elevated serum bile acids were the predominant symptom and laboratory finding during the fourth pregnancy. Both decreased during cholestyramine treatment. The bromsulphalein retention was quite normal six months after the third pregnancy but is still elevated two and a half years after the last one.