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Acyl glucuronides (AGs) are common, chemically reactive metabolites of acidic xenobiotics. Concerns about the potential of this class of conjugate to cause toxicity in man require efficient methods for the determination of reactivity, and this is commonly done by measuring transacylation kinetics. High-performance liquid chromatography-mass spectrometry (HPLC-MS) and nuclear magnetic resonance (NMR) spectroscopy were applied to the kinetic analysis of AG isomerization and hydrolysis for the 1-beta-O-AGs of ibufenac, (R)- and (S)-ibuprofen, and an alpha,alpha-dimethylated ibuprofen analogue. Each AG was incubated in either aqueous buffer at pH 7.4 or human plasma at 37 degrees C. Aliquots of these samples, taken throughout the reaction time course, were analysed by HPLC-MS and (1)H-NMR spectroscopy and the results compared. For identification of the AGs incubated in pH 7.4 buffer and for analysis of kinetic rates, (1)H-NMR spectroscopy generally gave the most complete set of data, but for human plasma the use of (1)H-NMR spectroscopy was impractical and HPLC-MS was more suitable. HPLC-MS was more sensitive than (1)H-NMR spectroscopy, but the lack of suitable stable-isotope labelled internal standards, together with differences in response between glucuronides and aglycones, made quantification problematic. Using HPLC-MS a specific 1-beta-O-AG-related ion at m/z 193 (the glucuronate fragment) was noted enabling selective determination of these isomers. In buffer, transacylation reactions predominated, with relatively little hydrolysis to the free aglycone observed. In human plasma incubations the observed rates of reaction were much faster than for buffer, and hydrolysis to the free aglycone was the major route. These results illustrate the strengths and weaknesses of each analytical approach for this class of analyte.

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The aim of this study was to compare the safety, tolerance, and diagnostic efficacy of iomeprol 350 mg I ml-1, iohexol 350 mg I ml-1, and iopamidol 370 mg I ml-1 in 90 adult patients undergoing intravenous urography. Radiographs obtained 5, 10 and 15 min after contrast injection were blindly graded for quality on a four point scale as: 0, non-diagnostic; 1, diagnostic but of limited quality; 2, diagnostic and of good quality; 3, fully diagnostic and of very good quality. The sum of these scores indicated the overall diagnostic quality (0-4, non-diagnostic; 4-8, diagnostic; 9-12, good or excellent). Contrast tolerability was evaluated by discomfort (heat or pain) associated with injection of the test compounds, and patients were monitored and questioned for adverse experiences. The quality of the individual radiographs was assessed as diagnostic and good or fully diagnostic and very good in most cases, with no significant differences between the three study groups, and overall scores were predominantly good or excellent (p = 0.55). All adverse reactions were transient and non-serious, and most of them were reported as mild in intensity. There were no significant differences between the three groups for heat sensation (p = 0.29). Pain at the injection site was reported only in the iohexol group (p = 0.104). It is concluded that iomeprol 350 mg I ml-1 is at least as safe and effective as iohexol 350 mg I ml-1 or iopamidol 370 mg I ml-1 when used for intravenous urography.

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1. Casodex, a non-steroidal antiandrogen, is a racemic mixture of R-Casodex, the pharmacologically active (-)-enantiomer, and S-Casodex, the inactive (+)-enantiomer. Single oral doses of pseudo-racemic 14C-Casodex (10 mg/kg), prepared from mixtures of either 14C-labelled R-Casodex and unlabelled S-Casodex, or 14C-S-Casodex and unlabelled R-Casodex, were administered to the intact and bile duct-cannulated male rat. 2. Neither enantiomer underwent stereochemical inversion, but the pharmacokinetics of Casodex showed marked enantioselectivity. 3. After dosing R-labelled Casodex, plasma concentrations of R-Casodex increased slowly to reach a peak of 3.50 +/- 0.05 micrograms/ml (mean +/- SEM) at 12 h and, thereafter, declined monoexponentially with an elimination half-life of 24 h. Plasma concentrations of S-Casodex rose rapidly to reach a much lower peak of 0.97 +/- 0.06 microgram/ml at 3 h and, thereafter, declined rapidly, although there were insufficient data to determine the half-life. R-Casodex had a much higher AUC0-24 (66 micrograms.h/ml) than S-Casodex (12 micrograms.h/ml). Plasma drug concentrations measured using an achiral assay were in very good agreement with the sum of the enantiomer concentrations throughout the profile. R-Casodex comprised 94% of the total plasma radioactivity at 12 h, decreasing to 75% at 120 h. 4. Plasma concentration data generated after administration of S-Casodex were similar to those observed after dosing R-labelled Casodex. S-Casodex comprised about 74% of the total plasma radioactivity at 6 h and only 41% at 24 h. 5. The urine of intact animals contained 36 +/- 2 and 48 +/- 3% of the dose respectively up to 48 and 120 h after dosing with R-labelled Casodex, and 33 +/- 4 and 34 +/- 4% respectively after dosing with S-labelled Casodex. The urine and bile of the cannulated rat contained 43 +/- 2 and 21 +/- 2% of the dose respectively up to 48 h after dosing with R-labelled Casodex and 37 (n = 2) and 50% respectively after dosing with S-labelled Casodex. 6. After dosing with R- or S-labelled Casodex, the urinary radioactivity consisted of the carboxylic acid metabolite formed by hydrolytic cleavage at the amide, whereas biliary radioactivity consisted of hydroxy-Casodex and Casodex, mainly conjugated with glucuronic acid. The clearance of R-Casodex by each of these pathways of metabolism was less than that of S-Casodex, with direct glucuronidation and hydroxylation showing greater enantioselectivity than hydrolysis.

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The aim of this double-blind, parallel group study was to compare the safety, tolerance and diagnostic efficacy of iomeprol 350 mgI/ml and iopromide 370 mgI/ml in 100 adult patients undergoing intravenous excretory urography. Fifty patients were randomised to receive 50 ml iomeprol 350 mgI/ml and 50 to receive 50 ml iopromide 370 mgI/ml. Intravenous administration of the contrast agents was always completed in 30 seconds. Images were obtained immediately after and 5, 10 and 15 min after completion of contrast medium injection. Nephrogram and pyelogram opacification quality was blindly graded according to a four point scale as follows: 0, nondiagnostic; 1, diagnostic but of limited quality; 2, diagnostic and of good quality; 3, fully diagnostic and of very good quality'. At the end of each individual patient study, the overall diagnostic quality of the procedure was reported as the sum of the scores attributed to each quality of nephrogram and pyelogram opacification quality on different images (0-4, nondiagnostic procedure; 4-8, diagnostic procedure; 9-12, excellent or good procedure). The tolerability of the test compounds was evaluated in terms of discomfort (heat and pain) associated with the injection of the test compounds. All patients were continuously monitored for adverse experiences for 1 h after completion of the urographic procedure. Reporting of untoward reactions was both spontaneous and elicited. The quality of the radiographs was judged as excellent or good in most cases, without significant differences between the two study groups. The distribution of scores of overall diagnostic quality of procedures was similar for the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)

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A 30-year-old man presented with a 7-month history of chronic partial priapism and sexual dysfunction following blunt perineal trauma. Duplex penile ultrasound confirmed high flow priapism and color flow Doppler ultrasound diagnosed an arteriovenous fistula within the left corpus cavernosum. This lesion was corrected via corporeal exploration and ligation of the artery feeding the fistula. The use of color flow Doppler ultrasound to diagnose this unusual condition obviated the need for angiographic studies. This rare condition of posttraumatic priapism may be diagnosed by noninvasive means. The pathophysiology, diagnosis and treatment of posttraumatic priapism and review of the literature are discussed.

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Untreated, progressive bilateral ureteric obstruction, or unilateral ureteric obstruction in patients with a solitary functioning kidney, will ultimately lead to uraemia, renal failure and death. This paper describes 34 successful percutaneous antegrade ureteric stent placements from 37 attempts, performed on 25 selected patients with a history of malignant disease, in whom retrograde ureteric stenting was impossible or difficult.

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1. Casodex, a non-steroidal antiandrogen, was eliminated primarily in faeces by rat, mouse, rabbit and dog. Rat, mouse and rabbit eliminated 20-30% of a single oral dose (8-25 mg/kg) in urine; only 3-4% was excreted in urine by dog (2.5 mg/kg). Oral absorption was about 80% in rat, mouse, rabbit and dog. 2. Most of the dose was recovered in 48 h from rat, mouse and rabbit. In rat, < 1% of the dose was exhaled as 14CO2 and < 1% remained in the carcass after 7 days. Recovery from dog was incomplete in 4 days but consistent with the long plasma elimination half-life of 7-7.5 days. Casodex was eliminated from rat plasma with a half-life of 17-21 h. 3. Examination of urine indicated extensive metabolism of Casodex and showed a marked species difference. In rat, mouse and dog, Casodex was cleaved at the amide to yield a carboxylic acid and an aromatic amine which subsequently underwent ring hydroxylation with sulphate conjugation. In rabbit, the major urinary metabolite was Casodex glucuronide, conjugated on the tertiary hydroxyl. 4. The major component in faeces of all species was unchanged Casodex; some hydroxy-Casodex was also observed in rat faeces. Analysis of rat and dog bile indicated that Casodex and hydroxy-Casodex were eliminated in bile primarily as glucuronide conjugates.

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To assess its reliability as a marker of cardiomegaly in elderly patients, we compared a clinical assessment of heart size with that calculated from chest radiography. In 100 hospitalized subjects of median age 78 years, the apex beat was palpable in only 35% and its palpability declined with increasing age. Even when palpable, the apex beat had low specificity (74%) and sensitivity (69%) as a marker of cardiomegaly and its positive predictive value (69%) and negative predictive value (74%) were poor. The clinical assessment of heart size in elderly hospitalized patients should be interpreted with caution.

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1. Following intravenous administration of 14C-tert-butyl-D-serine to rats, radioactivity was eliminated rapidly via the kidneys. 2. One metabolite was detected in urine and was identified as the N-acetyl derivative of tert-butyl-serine. 3. Elimination was more rapid in female than male rats.

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