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In nine chronic haemodialysis patients, treated alternately with acetate and bicarbonate, the main critical factors in oxygen supply to the tissues were evaluated: Hb values, blood gas parameters, red cell 2-3 diphosphoglycerate (2-3 DPG), phosphataemia and P50 in vivo. Predialytic P50 was higher than in normal controls. During dialysis, arterial pO2 and pCO2 significantly decreased in acetate dialysis, whereas they were stable in bicarbonate dialysis. Rising alkalinisation was accompanied, both in acetate dialysis and in bicarbonate dialysis, by reduction of P50, while 2-3 DPG did not change. The acute increase in Hb-O2 affinity adversely affected peripheral oxygen release. In acetate dialysis this mechanism might magnify the effects of dialysis-induced hypoxaemia, affecting the clinical tolerance.

A comparison between two ICP-MS methods and HPLC with electrochemical detection (ED) for the determination of iodine is described. The first ICP-MS method involves 10-fold dilution with water using Rh as internal standard and the calibration graph was obtained with a synthetic urine. In the second ICP-MS method the sample preparation provided a 5-fold dilution with water using In as internal standard and adding nitric acid and the calibration graph was obtained by making additions to a pool of human urine samples. In the HPLC method, the urine was previously purified from organic substances through an SPE C18 column and the final portion was collected. The chromatographic column used was a C18 reversed-phase column and a silver working electrode was used versus a Pd/Pt reference electrode for ED. The calibration graph was obtained with a synthetic urine. The results show that the two ICP-MS methods are comparable in terms of analytical parameters such as precision and limit of detection. Good agreement between both ICP-MS procedures and HPLC–ED was also obtained, although the limit of detection was higher in HPLC–ED and the linear dynamic range was wider in both ICP-MS methods.

Oxidation of optically active esters of o-(methylthio)benzoic acid with achiral peroxy-acids (perbenzoic and 2,4,6-trimethylperbenzoic acids) yields mixtures of the corresponding diastereomeric sulphoxides, enriched in one of the components. Hydrolysis affords optically active o-methylsulphinylbenzoic acid. The absolute chirality of the latter depends on the chirality of the inducing alcohol. The optical yields are noticeably higher with the bulkier trimethylperbenzoic acid. The asymmetric induction is interpreted in terms of eclipsing effects of small, medium, and large groups. A correlation model, based on those conformations of the diastereomeric transition states which present the largest difference of steric compression, is suggested.