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Urine and plasma samples from 39 patients who underwent renal transplantation were analyzed by proton nuclear magnetic resonance (NMR) spectroscopy. The most relevant resonances for evaluating renal function after transplantation were those arising from citrate, trimethylamine-N-oxide (TMAO), alanine, and lactate when compared to creatinine. A resonance at 3.7 ppm was related to cyclosporine toxicity when associated with elevated levels of TMAO. The respective variations in these metabolites in urine could contribute to prognosis and diagnosis of renal function impairment related to cyclosporine toxicity or overdosage, or to rejection. Thus, NMR spectroscopy should improve the follow-up and management of renal transplantation patients.

Comparison of 1α-hydroxycholecalciferol and 25-hydroxycholecalciferol in the treatment of renal osteodystrophy: Greater effect of 25-hydroxycholecalciferol on bone mineralization. A comparison was made of the biochemical and osseous effects of 1α-OH vitamin D 3 and 25-OH vitamin D 3 in uremic men on chronic hemodialysis. Two groups of patients dialyzed in the same center were matched for their plasma concentrations of calcium (P Ca ), phosphate (P PO 4 ), immunoreactive parathyroid hormone (P iPTH ), 25-OH vitamin D (P 25–OH–D ), their serum alkaline phosphatase (Alk. Pase), and their degree of osteomalacia as assessed on bone histomorphometry. The first group received 1α-OH-D 3 for 2 to 9 months at a mean daily dosage of 1 to 2 µg, and the second group received 25-OH-D 3 for 1 to 6 months at a mean daily dosage of 50 to 100 µg. The 1α:-OH-D 3 therapy was more effective than the 25-OH-D 3 therapy was in increasing the P Ca × P PO 4 product, in decreasing the serum Alk. Pase and the percent of osteoblastic surface (OB). On the other hand, 25-OH-D 3 therapy initially increased bone formation and was more effective than was the 1α-OH-D 3 in increasing the mineralization front (MF). In one patient, in which the MF did not increase after 9 months of 1α-OH-D 3 , it increased from 34.0 to 44.6% after addition of 25-OH-D 3 . Increased serum calcium occurred earlier with 1α-OH-D 3 than it did with 25-OH-D 3 (2 vs. 8 weeks), and reversal of hypercalcemia was more rapid after withholding treatment with 1α-OH-D 3 than it was with 25-OH-D 3 (1 vs. 4 weeks). It is concluded that (1) large dosages of 25-OH-D 3 , rather than "physiologic" dosages of 1α-OH-D 3 , induce more effectively bone mineralization in spite of a smaller increase of the P Ca × P PO 4 product and may be therefore a better treatment for a renal osteomalacia; (2) the more rapid reversal of hypercalcemia induced by 1α-OH-D 3 , however, makes the use of this latter less hazardous than that of 25-OH-D 3 . Comparison du 1α-hydroxycholecalciferol et du 25-hydroxycholecalciferol dans le traitement de l'osteodystrophie renale: Efficacite superieure de 25-hydroxycholecalciferol sur la mineralisation de l'os. On a compare les effets osseux et biochimiques de la 1α-OH-vitamine D 3 et de la 1α-25-OH vitamine D 3 sur deux groupes de malades uremiques en hemodialyse chronique. Les deux groupes etaient dialyses dans le meme centre et etaient comparables au depart en ce qui concerne leurs concentrations plasmatiques de calcium (P Ca ), de phosphore (P PO 4 ) d'hormone parathyroidienne immunoreactive (P iPTH ), de 25-OH vitamine D (P 25–OH–D ,) leurs phosphatases alcalines seriques et leur degre d'osteomalacie appreciee par histomorphometrie. Le premier groupe a recu de la 1α-OH-D 3 pendant 2 to 9 mois a la dose journaliere moyenne de 1 a 2 µg et le second groupe a recu de la 25-OH-D 3 pendant 1 a 6 mois a la dose journaliere moyenne de 50 a 100 µg. La 1α-OH-D 3 a ete plus efficace que la 25-OH-D 3 dans l'augmentation du produit phosphocalcique, la diminution des phosphatases alcalines et de la surface osteoblastique. A l'oppose 1a 25-OH-D 3 entraina une augmentation initiale de la formation osseuse et a ete plus efficace que la 1α-OH-D 3 dans l'augmentation du front de mineralisation (FM). Chez un malade, le FM qui n'avait pas augmente apres 9 mois de 1α-OH-D 3 , s'accrut de 34,0% a 44,6% apres addition de 25-OH-D 3 . L'augmentation de la calcemie est survenue plus rapidement avec la 1α-OH-D 3 qu'avec la 25-OH-D3 (2 semaines contre 8 semaines) et la correction de l'hypercalcemie a ete plus rapide apres l'arret de la 1α-OH-D 3 qu'apres arret de la 25-OH-D 3 (1 semaine contre 4 semaines). En conclusion (1) de fortes doses de 25-OH-D 3 sont plus efficaces que des doses "physiologiques" de 1α-OH-D 3 pour augmenter la mineralisation osseuse en depit d'une moindre augmentation du produit phosphocalcique et pourraient ainsi representer un meilleur traitement de l'osteomalacie renale; (2) la correction plus rapide de l'hypercalcemie induite par la 1α-OH-D 3 rend cependant l'usage de cette derniere moins dangereux que celui de la 25-OH-D 3 .