Urea rebound refers to an early postdialysis phenomenon in which urea returns to the systemic circulation, raising the blood level to a near plateau over a period of 0.5 to 1 hour [1]. The urea involved is believed to have come from either the intracellular compartment by means of diffusion resulting from the dialysis-induced concentration gradient [2,3], or tissues poorly perfused as a result ...

Fifty-eight crossbred yearling heifers (BW = 383 ± 25 kg) were utilized in a completely randomized 2 x 2 factorial arrangement of treatments designed to evaluate the effects of finishing diets containing dried distiller's grains supplemented with degradable intake protein on feedlot performance and carcass characteristics. Dietary treatments contained 10 or 20% dried distiller's grains (DDG) re...

The measurement of blood urea nitrogen (BUN) as serum or plasma urea is one of the most frequently ordered laboratory tests for evaluating renal functions. Conventional analysis of reactions of urea with diacetyl monoxime or urease with the Berthelot reaction [1] is rapidly giving way to the totally enzymatic reactions that are more convenient to perform and more easily adapted to modern instru...

Urea kinetic modeling measures the delivered dose of hemodialysis and is used to monitor dialysis adequacy. Obtaining samples for adequacy calculations is a challenge for home hemodialysis (HHD) patients. Ideally, the urea reduction ratio (URR) should be measured at a typical dialysis session; therefore, for HHD patients test specimens should be drawn at home and transferred to a clinical labor...

We developed a new urea sensor for the on-line monitoring of hemodialysis adequacy. The biosensor consisted of an immobilized urease cartridge placed between magnetoinductive conductivity cells. The biosensor output was taken as the conductivity difference between these cells. The device was placed on the ultrafiltrate line of a paired filtration dialysis system. The amount of urease present in...

Previous research indicates that high blood urea nitrogen (BUN) concentrations are associated with decreased fertility in lactating dairy cows.This experiment was done to evaluate the effects of equine chorionic gonadotropin (eCG) administration (with or without eCG) on fertility of lactating dairy cows with different levels of BUN subjected to fixed-time artificial insemination (FTAI).Ovulatio...

Sir, Dehydrated patients usually present with elevated blood urea nitrogen (BUN) concentrations, reflecting a low urine flow rate and increased renal reabsorption of urea. This increased renal reabsorption of urea is thought to owe at least in part to the action of antidiuretic hormone (ADH). A 44-year-old Japanese man with mental retardation was admitted because of the recent onset of polyposi...

Eight Angus heifer calves (234 kg) were assigned to either a high (HP; 126 g N/d) or low (LP; 66.5 g N/d) protein intake. Calves received 4.8 kg DM/d consisting of 30% cottonseed hulls and 70% corn-soybean meal in equal portions at 4-h intervals. Single doses of 14C- and 15N-urea and 15N-ammonium sulfate were injected into the blood urea-N (BUN) and ruminal NH3-N (RAN) pools, respectively, to m...

In vitro, 7 days of high blood urea nitrogen (BUN) inhibits endothelial L-arginine transport and nitric oxide synthase (NOS) activity. The present study investigates whether 7 days of high BUN in vivo influences renal hemodynamics, blood pressure (BP), and/or the nitric oxide (NO) system. Normal rats were fed low-nitrate food containing 30% urea for 7 days, which increased BUN (15 +/- 1 to 69 +...