BACKGROUND Reverse iontophoresis uses a small current to extract molecules and ions through the skin. The aim of the study was to determine whether reverse iontophoresis of urea can be used (i) to diagnose and monitor non-invasively chronic kidney disease (CKD), and (ii) to track urea levels closely during a hemodialysis session. METHODS A current of 0.8mA was applied for 2h in 10 healthy vol...

Urea clearance was determined on 25 healthy male medical students at Surabaja, Indonesia. The age of the subjects varied from 20 to 25 years, the average being 23 years. The subjects reported to the laboratory at 8 a.m., when they voided urine and then rapidly drank 500 m!. of iced water. At 9 a.m. they passed urine which was collected and measured, and 5 m!. of blood was withdrawn by vcnepuncl...

When compared to intermittent dialysis, the theoretical advantages of continuous dialysis may be less important than its practical disadvantage: the inability to accurately quantify dialysis. With intermittent dialysis the change in blood urea nitrogen over the course of the treatment allows the ratio of K (urea clearance) to V (volume of distribution of urea or total body water) to be determin...

It has been observed experimentally that early distal tubular urea flow exceeds urea delivery by the proximal convoluted tubule to the pars recta and loop of Henle. Moreover, the fractional excretion of urea in the urine may exceed values compatible with the reabsorption known to occur in the proximal convoluted tubule in the cortex. A likely explanation for these observations is that urea may ...

Automated and manual direct methods for the determination of urea in blood or serum are described. These methods determine urea by the colored product formed when urea, in relatively weak acid solution, reacts with diacetyl monoxime in the presence of thiosemicarbazide and ferric ion. Results are compared with those obtained by urease conversion of urea to ammonia and measurement of the ammonia...

Measurement of blood flow rate (Qa) is used to monitor arteriovenous fistulas and grafts that are used for hemodialysis blood access. Most Qa measurements use indicator dilution techniques to measure the recirculation that is induced by the reversal of hemodialysis blood lines. R plus the dialysis circuit flow (Qb) allows the calculation of Qa. The principle of needle reversal also can be used ...

The objective of this review is to describe recent research findings related to the use of milk or blood urea nitrogen to identify inefficiencies in protein nutrition and estimate nitrogen excretion. A mathematical model was developed to integrate milk urea nitrogen (MUN) and milk composition to predict urinary and fecal excretion, intake, and utilization efficiency for nitrogen in lactating da...

Hypertonic solutions play an important role in the treatment of tissue edema. Following the induction of experimental vasogenic brain edema by occlusion of the common carotid arteries in eight rabbits, the effect of hypertonic lactated Ringer's solution (subjects), vs. isotonic lactated Ringer's solution (control), was studied on blood pressure, electrolyte (sodium, potassium, and calcium) ...

BACKGROUND AND PURPOSE (13)C-urea may be a suitable marker to assess the in vivo fate of colon-targeted dosage forms given by mouth. We postulated that release in the colon (urease-rich segment) of (13)C-urea from colon-targeted capsules would lead to fermentation of (13)C-urea by bacterial ureases into (13)CO(2). Subsequent absorption into the blood and circulation would lead to detectable (13...