Down syndrome (DS) is a genetic disorder resulting from trisomy 21 that causes cognitive impairment, low muscle tone and craniofacial alterations. Morphometric studies of the craniofacial and appendicular skeleton in individuals with DS suggest that bone development and homeostasis are affected by trisomy. The Ts65Dn mouse model has three copies of approximately half the genes found on human chromosome 21 and exhibits craniofacial skeletal and size differences similar to those observed in humans with DS. We hypothesized that Ts65Dn and euploid mice have distinct differences in bone development and homeostasis influencing both the craniofacial and appendicular skeletal phenotypes. Quantitative assessment of structural and mechanical properties of the femur in Ts65Dn and control mice at 6 and 16 weeks of age revealed significant deficiencies in trabecular and cortical bone architecture, bone mineral density, bone formation, and bone strength in trisomic bone. Furthermore, bone mineral density and dynamic dentin formation rate of the skull and incisor, respectively, were also reduced in Ts65Dn mice, demonstrating that trisomy significantly affects both the craniofacial and appendicular skeleton.

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Background Uromodulin is a protein made only by the kidney and released in urine, circulating in polymerizing and nonpolymerizing forms. This protein's multiple functions include inhibition of stone formation in the urine. The physiological determinants of uromodulin production are incompletely understood. Methods We investigated changes in uromodulin levels and key factors governing its production and release in urine and serum. We performed an experiment to determine whether water loading, a common intervention to prevent stone formation, will alter the rate of uromodulin production. During a 2-day period, 17 stone forming participants and 14 control participants were subjected to water loading (day 1) and normal fluid intake (day 2). Uromodulin levels were measured on timed hourly collections in urine and plasma during the period of the study. Results Water loading increased urinary uromodulin secretion (33±4 versus 10±4 μg/min at baseline, P < 0.0001) in stone formers and control participants. Despite high urine volumes, most participants maintained relatively stable urinary uromodulin concentrations. Native Western blots for polymerizing and nonpolymerizing uromodulin suggest that polymerizing uromodulin was the predominant form at higher urinary flow volumes. Urine flow rates and sodium excretion were significant correlates of urinary uromodulin production. Water loading did not affect serum uromodulin levels, which were also not associated with urinary uromodulin. Conclusions Water loading increases the secretion of polymerizing urinary uromodulin. This increased secretion reduces the variability of urinary uromodulin concentrations despite high urine volumes. Serum uromodulin levels were not affected by this treatment.

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Chronic kidney disease guidelines and disease modifying therapy have seen a dramatic shift in the last 5 years. The SGLT2 inhibitor class of medications has been catapulted from hyperglycemia management medications, to cardiovascular and kidney disease improvement therapies. Multiple trials looking at dedicated cardiovascular and kidney endpoints have resulted in favorable results. This review will target empagliflozin and the exciting journey that it has taken along this path. Empagliflozin has been studied for hyperglycemia, cardiovascular, and kidney hard outcome endpoints. Both patients with diabetes and without have been rigorously studied and shown surprising results. The major implications for patients on empagliflozin will be shown. Future studies and directions are highly anticipated to add to the growing knowledge of the SGLT2 inhibitor class, as well as discover possibilities for new disease states to benefit from empagliflozin.

<b><i>Introduction:</i></b> Calcification on native kidney biopsy specimens is often noted by pathologists, but the consequence is unknown. <b><i>Methods:</i></b> We searched the pathology reports in the Biopsy Biobank Cohort of Indiana for native biopsy specimens with calcification. <b><i>Results:</i></b> Of the 4,364 specimens, 416 (9.8%) had calcification. We compared clinical and histopathology findings in those with calcification (<i>n</i> = 429) compared to those without calcification (<i>n</i> = 3,936). Patients with calcification were older, had more comorbidities, lower estimated glomerular filtration rates (eGFR), were more likely to have hyaline arteriosclerosis, interstitial fibrosis/tubular atrophy, and a primary pathologic diagnosis of acute tubular injury or acute tubular necrosis when compared to patients without calcification. Patients with calcium oxalate deposition alone, compared to calcium phosphate or mixed calcifications, had fewer comorbidities but were more likely to have a history of gastric bypass surgery or malabsorption and take vitamin D. In patients with two or more years of follow-up, multivariate analyses showed the presence of calcification (HR 0.59, 0.38–0.92, <i>p</i> = 0.02) and higher eGFR (HR 0.76, 0.73–0.79, <i>p</i> &#x3c; 0.001), was associated with decreased likelihood of progressing to end-stage renal disease. The presence of calcification was also associated with a reduced slope/decline in eGFR compared to known biopsy and clinical risk factors for decline in kidney function. We hypothesized this was due to more recoverable acute kidney injury (AKI) and found more severe acute kidney injury network stage in patients with kidney calcification but also greater improvement over time. <b><i>Discussion/Conclusion:</i></b> In summary, we demonstrated that calcification on kidney biopsy specimens was associated with a better prognosis than those without calcification due to the association with recoverable AKI.