Experience with tacrolimus in children with steroid-resistant nephrotic syndrome

Children with steroid-resistant nephrotic syndrome (SRNS) are at risk of developing renal failure. We report here the results of a single-center retrospective observational study of the remission rate in pediatric patients with SNRS receiving tacrolimus. Serial renal biopsies from children on tacrolimus therapy were evaluated for tubulointerstitial fibrosis and transforming growth factor-β immunostaining. Of the 16 children with SRNS, 15 went into complete remission after a median of 120 days of therapy. Nine children were able to stop steroids, while the others were on tapering doses. Forty-seven percent had relapses, most of which were steroid-responsive. Serial renal biopsies were obtained from seven children after a median treatment duration of 24 months; two of these children had increased tubulointerstitial fibrosis and four showed increased transforming growth factor-β tissue staining. Children with worsening histological findings were younger. There was no significant association between tacrolimus exposure and biopsy changes, although the average trough level was higher in those children with worsening histological findings. In conclusion, tacrolimus may be a safe and effective alternative agent for inducing remission in children with SRNS. However, caution needs to be taken when prescribing this agent due to its narrow therapeutic index. Serial renal biopsies are necessary to check for subclinical nephrotoxicity, especially in younger children and those with higher trough levels

Thermodynamic study of orthorhombic Tx and tetragonal T′ lanthanum cuprate, La2CuO4

The enthalpies of transition among the Tx, T′, and T–La2CuO4 phases are obtained from a combination of differential scanning calorimetry, high temperature oxide melt solution calorimetry, and transposed temperature drop calorimetry. The enthalpy of transformation of Tx to T is 2.32±0.07 kJ/mol and the corresponding entropy of transition is 4.38±0.13 J/(mol K). The T′ modification, with an average of 1.40 kJ/mol, is less stable in enthalpy than Tx but at 0.96 kJ/mol, more stable in enthalpy than T. Although we cannot rule out a small stability field at temperatures near the Tx–T transition at 530 K, T′ is most likely metastable at all temperatures