3 siblings – 2 brothers aged 18 and 13 years, and 1 sister, aged 11 years – with adolescent or late-onset cystinosis presented with massive proteinuria. At the time their glomerular filtration rate was normal or only modestly diminished. Though glomerular injury was evident, renal tubular functional abnormalities were also present. Renal biopsy revealed histopathologic features typical of the nephropathic form of cystinosis with the Fanconi syndrome: polykaryocytosis, varying degrees of glomerular sclerosis, thickening and reduplication of basement membrane, fused foot processes, dilated tubules with altered epithelial cell features, and interstitial fibrosis. Fine granular deposits of C₃ and IgM are irregularly distributed in the glomeruli, findings which have not been described in cystinosis. These deposits are possibly immune complexes being deposited in the glomeruli unrelated to the cystine-storage disease or they may represent a localized activation of the complement system induced by the glomerular injury of cystinosis.

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SummaryKnowledge of elemental distribution and concentration within plant tissues is crucial in the understanding of almost every process that occurs within plants. However, analytical limitations have hindered the microscopic determination of changes over time in the location and concentration of nutrients and contaminants in living plant tissues.We developed a novel method using synchrotron-based micro X-ray fluorescence (μ-XRF) that allows for laterally-resolved, multi-element, kinetic analyses of plant leaf tissues in vivo. To test the utility of this approach, we examined changes in the accumulation of Mn in unifoliate leaves of 7-d-old cowpea (Vigna unguiculata) plants grown for 48 h at 0.2 and 30 μM Mn in solution.Repeated μ-XRF scanning did not damage leaf tissues demonstrating the validity of the method. Exposure to 30 μM Mn for 48 h increased the initial number of small spots of localized high Mn and their concentration rose from 40 to 670 mg Mn kg-1 fresh mass. Extension of the two-dimensional μ-XRF scans to a three-dimensional geometry provided further assessment of Mn localization and concentration.This method shows the value of synchrotron-based μ-XRF analyses for time-resolved in vivo analysis of elemental dynamics in plant sciences.