Urinary extracellular vesicle-associated MCP-1 and NGAL derived from specific nephron segments differ between calcium oxalate stone formers and controls.

Randall's plaque (RP; subepithelial calcification) appears to be an important precursor of kidney stone disease. However, RP cannot be noninvasively detected. The present study investigated candidate biomarkers associated with extracellular vesicles (EVs) in the urine of calcium stone formers (CSFs) with low (<5% papillary surface area) and high (≥5% papillary surface area) percentages of RP and a group of nonstone formers.

Heritability of dietary traits that contribute to nephrolithiasis in a cohort of adult sibships.

Background: Kidney stones and their risk factors aggregate in families, yet few studies have estimated the heritability of known risk factors.

Objective: Estimate the heritability of dietary risk factors for kidney stones.

Methods: Dietary intakes were assessed using the Viocare Food Frequency Questionnaire in sibships enrolled in the Rochester, MN cohort of the Genetic Epidemiology Network of Arteriopathy.

Distinguishing characteristics of idiopathic calcium oxalate kidney stone formers with low amounts of Randall's plaque.

Background: Overgrowth of calcium oxalate on Randall's plaque is a mechanism of stone formation among idiopathic calcium oxalate stone-formers (ICSFs). It is less clear how stones form when there is little or no plaque.

Design, Setting, Participants, & Measurements: Participants were a consecutive cohort of ICSFs who underwent percutaneous nephroscopic papillary mapping in the kidney or kidneys containing symptomatic stones and a papillary tip biopsy from a representative calyx during a stone removal procedure between 2009 and 2013.

Sulfate but not thiosulfate reduces calculated and measured urinary ionized calcium and supersaturation: implications for the treatment of calcium renal stones.

Background: Urinary sulfate (SO4(2-)) and thiosulfate (S2O3(2-)) can potentially bind with calcium and decrease kidney stone risk. We modeled the effects of these species on the concentration of ionized calcium (iCa) and on supersaturation (SS) of calcium oxalate (CaOx) and calcium phosphate (CaP), and measured their in vitro effects on iCa and the upper limit of stability (ULM) of these salts.

Methods: Urine data from 4 different types of stone patients were obtained from the Mayo Nephrology Clinic (Model 1).

Heritability of urinary traits that contribute to nephrolithiasis.

Background And Objectives: Kidney stones and their risk factors aggregate in families, yet few studies have systematically estimated heritabilities and genetic correlations of the numerous urinary traits associated with risk of kidney stones.

Design, Setting, Participants, & Measurements: Twenty-four-hour urine samples were collected from the Genetic Epidemiology Network of Arteriopathy cohort of families in Rochester, Minnesota, to measure urinary determinants of supersaturation. Diet was assessed using the Viocare food frequency questionnaire.

Key role of alkaline phosphatase in the development of human-derived nanoparticles in vitro.

Alkaline phosphatase (ALP) is an enzyme critical for physiological and pathological biomineralization. Experiments were designed to determine whether ALP participates in the formation of calcifying nanometer sized particles (NPs) in vitro. Filtered homogenates of human calcified carotid artery, aorta and kidney stones were inoculated into cell culture medium containing 10% fetal bovine serum in the absence or presence of inhibitors of ALP or pyrophosphate.