Overcoming the effects of matrix interference in the measurement of urine protein analytes.

Using multiplex bead assays to measure urine proteins has a great potential for biomarker discovery, but substances in urine (the matrix) can interfere with assay measurements. By comparing the recovery of urine spiked with known quantities of several common analytes, this study demonstrated that the urine matrix variably interfered with the accurate measurement of low abundance proteins. Dilution of the urine permitted a more accurate measure of these proteins, equivalent to the standard dilution technique when the diluted analytes were above the limits of detection of the assay.

Insulin's actions on plasma free fatty acids are normal in patients with stage 2 to 3 chronic kidney disease.

Resistance to insulin's action to suppress plasma nonesterified fatty acids (NEFA) is implicated in the hypertension and hyperlipidemia characterizing the metabolic syndrome. It is unknown whether insulin resistance to NEFA suppression is linked to hypertension and dyslipidemia in patients with mild chronic kidney disease (CKD). Eight patients with nonnephrotic, nondiabetic stage 2 to 3 CKD (I(125)-iothalamate clearances of 56 +/- 6 mL/min) and 7 hypertensive (HT) and 8 normotensive (NT) subjects with normal kidney function matched for age, gender, race, and percent body fat were studied.

Mechanism of lipid enhancement of alpha1-adrenoceptor pressor sensitivity in hypertension.

Objective And Design: Plasma lipids enhance alpha1-adrenoceptor pressor sensitivity, impair baroreflex function, and correlate with increased blood pressure. This clinical study was designed to determine whether the enhanced alpha1-pressor sensitivity induced by acute hyperlipidemia is primarily mediated by increased vascular alpha1 responsiveness, reduced baroreflex sensitivity (BRS) or both.

Method: Regional alpha1-adrenoceptor vasoreactivity was measured using a graded brachial artery infusion of the alpha1 agonist, phenylephrine, in seven subjects with stage 1 hypertension.

Prediction of urinary protein markers in lupus nephritis.

Background: Lupus nephritis is divided into six classes and scored according to activity and chronicity indices based on histologic findings. Treatment differs based on the pathologic findings. Renal biopsy is currently the only way to accurately predict class and activity and chronicity indices.

Glomerular filtration rate can be accurately predicted using lean mass measured by dual-energy X-ray absorptiometry.

Background: Accurate assessment of renal function is important in the management of patients with kidney disease yet is often difficult to obtain. Formulae, designed for clinical use, have been developed to predict glomerular filtration rate (GFR) utilizing serum creatinine (Scr). Additional parameters are included in these formulae to account for variations in Scr due to differences in total body lean mass in kg (LM).