European uroradiological training

Approved by the membership at the Third General Assembly of the European Society of Uroradiology in Florence, Italy, 11 September 1994     

Influence of Fatty Acids on the Binding of Warfarin and Phenprocoumon to Human Serum Albumin with Relation to Anticoagulant Therapy

Warfarin and phenprocoumon binding to human serum albumin was studied by equilibrium dialysis. The first stoichiometric binding constant was 1.89 × 10⁵ M^?1 for warfarin and 2.40 × 10⁵ M^?1 for phenprocoumon. The affinity of warfarin was markedly increased on addition of up to 3 mol mol^?1 albumin of palmitic, stearic, oleic or linoleic acids with energetic couplings for co-binding of one molecule of each of the fatty acids and one molecule of warfarin of 0.9, 1.1, 0.7 and 0.6 kJ mol^?1, respectively. The affinity of phenprocoumon was only increased slightly on addition of palmitate with an energetic coupling of 0.3 kJ mol^?1. Six consecutive serum samples were obtained from each of 14 patients undergoing surgery. The serum affinity of the drugs varied considerably corresponding to free drug concentrations between 0.7 and 2.7% for warfarin and between 0.8 and 4.9% for phenprocoumon. The affinity of warfarin but not of phenprocoumon was correlated to the increasing plasma fatty acid concentration. Anticoagulant therapy with phenprocoumon may thus be less sensitive than warfarin to changes in the fatty acid concentration of plasma.     

Significance of Serum S100 Release After Coronary Artery Bypass Grafting

Background. S100 protein has been suggested to be a serum marker for cerebral complications after cardiac operation and extracorporeal circulation. The aim of this study was to characterize the S100 release pattern after extracorporeal circulation in 515 consecutive patients undergoing coronary artery bypass grafting.

Methods. Clinical variables and outcome were prospectively registered. The cerebral outcome was determined by clinical examination. S100 was measured at the end of extracorporeal circulation, and after 5, 15, and 48 hours.

Results. After operation, 13 patients had stroke, 12 had delayed awakening, and 17 had encephalopathy. Early S100 release, immediately after extracorporeal circulation, was associated with age and perfusion time, but not with cerebral outcome. However, S100 release after 5 to 48 hours was associated with cerebral complications and risk factors for such outcome. Patients with stroke had higher S100 levels after 15 to 48 hours. A subset of patients with renal failure had overall higher S100 levels at 5 hours.

Conclusions. Early and late S100 release indicate different mechanisms for release and emphasizes the potential power of this new biochemical marker for cerebral damage.     

Can differences in medical drug compliance between European countries be explained by social factors: analyses based on data from the European Social Survey, round 2

Background  

Non-compliance with medication is a major health problem. Cultural differences may explain different compliance patterns. The size of the compliance burden and the impact of socio-demographic and socio-economic status within and across countries in Europe have, however, never been analysed in one survey. The aim of this study was to analyse 1) medical drug compliance in different European countries with respect to socio-demographic and socio-economic factors, and to examine 2) whether cross-national differences could be explained by these factors.     

Lymphocyte subsets in the cerebrospinal fluid in active multiple sclerosis

We studied the relative number of lymphocyte subsets in the cerebrospinal fluid (CSF) of patients with active multiple sclerosis. The cells were double-labeled with monoclonal antibodies and were studied using a fluorescence-activated cell analyzer. The number of Leu2+Leu15+ cells and Leu3+Leu18+ cells was markedly reduced in the CSF but not in the peripheral blood of the patients. The number of Leu3+Leu18+ cells was reduced also in the CSF of control patients (patients with other inflammatory or infectious neurological diseases).     

Diversity in rat tissue accumulation of vitamin B12 supports a distinct role for the kidney in vitamin B12 homeostasis.

BACKGROUND: Vitamin B(12) in plasma is complexed to the carrier proteins transcobalamin (TC) and haptocorrin. The TC-B(12) complex is filtered in the glomeruli and reabsorbed in the renal tubules by receptor-mediated endocytosis, providing a route for a significant renal accumulation of vitamin B(12). The present study investigates the role of the rodent kidney in B(12) homeostasis by examining the distribution of vitamin B(12) in rats during vitamin B(12) depletion or B(12) load, and compares kidney accumulation with the vitamin distribution in other tissues including brain, liver, testes, intestine, spleen and plasma. METHODS: Fifteen rats were fed on a diet containing different concentrations of B(12) supplemented with s.c. injections of B(12). Twenty four hours prior to sacrifice, all animals were injected with [(57)Co]B(12). The vitamin contents of kidneys, liver, spleen, brain, testis, intestine, skeletal muscle, serum and urine were analysed. Both total tissue vitamin B(12) accumulation and [(57)Co]B(12) were determined to compare steady-state B(12) and the distribution of an acutely injected dose. In the kidney, free and protein-bound B(12) was determined by gel filtration. RESULTS: The rat kidneys accumulated more B(12) during normal and loaded conditions than any other tissue. A 110-fold increase in vitamin content was observed from the deficient to the loaded conditions in the kidney compared with a 3.5-fold increase in the liver. In contrast to all other organs, significantly smaller amounts of acutely injected B(12) accumulated in the kidneys in the vitamin-deprived state compared with both the normal and the vitamin-loaded condition. CONCLUSIONS: The present study suggests a significant role for the rodent kidney in vitamin B(12) metabolism. We propose a model for rat tissue uptake consistent with the presence of two different TC-B(12) receptors and renal uptake following filtration of TC-B(12) in the glomeruli. The presented model allows for the reduced renal uptake and accumulation in vitamin-deprived conditions, thus reserving the vitamin for other tissues, including nerve tissue and bone marrow, which are more sensitive to vitamin B(12) deficiency.