The cyclotron-produced radionuclide, 13N, was used to label ammonia and to study its metabolism in a group of 5 normal subjects and 17 patients with liver disease, including 5 with portacaval shunts and 11 with encephalopathy. Arterial ammonia levels were 52-264 micron. The rate of ammonia clearance from the vascular compartment (metabolism) was a linear function of its arterial concentration: ...

Hyperammonemia has been reported to be associated with patients who receive valproic acid (VPA) therapy. This study aimed to determine the risk factors for hyperammonemia in patients with epilepsy treated with VPA. One hundred and fifty-eight adult patients with epilepsy aged older than 17 years who received VPA therapy were enrolled into this study. Blood samples were taken during the interict...

BACKGROUND AND AIM Helicobacter pylori (H. pylori) bacteria convert urea to ammonia, which has been implicated in causation of hepatic encephalopathy in patients with liver cirrhosis. The role of H. pylori infection in causation of minimal hepatic encephalopathy (MHE) has not been well studied. We looked at the relationship of H. pylori infection with MHE and hyperammonemia in patients with liv...

Lethal infections by Staphylococcus aureus and Klebsiella pneumoniae were compared for kidney-related effects in mice. K. pneumoniae caused uremia and an increase in blood ammonia that could reach 2.5 times normal. These events did not occur in mice inoculated with S. aureus. Use of germfree animals indicated that most of the increase in ammonia arose from the gut, presumably due to greater ava...

Laboratory studies have been made to evaluate two methods for removing ammonia from blood:-1 The twin-coil artificial kidney was found to produce significant reductions in the ammonia content of outdated human banked blood. After one passage through the coil, levels of up to 9 mug. of ammonia nitrogen per millilitre were reduced to normal, and this effect was maintained when up to 5 litres were...

Since the ammonia undergoes a 3-electron change, 1 mole is equal to 3 equivalents of the generated titrant. Recently we (lescril)ed an improved cud-point (letection for this system and applied it to titration of as little as 1.4 g. ammonia (2). This method has been extended to titration of ammonia formed by the action of urease on urea in blood and urine. In urine samples, ammonia may be titrat...

According to the usually accepted concept, the urea removed from the blood by the kidneys is excreted in two forms, chiefly as urea itself, but partly as ammonia. That the ammonia of the urine is formed in the kidneys was demonstrated by Nash and Benedict (1921), in work which has been confirmed by other authors (cf. Peters and Van Slyke, I, p. 373). Evidence from animal experiments in v4vo has...

Ammonium salts have been shown to have significantly different toxicities (LD,0's) when administered intravenously under controlled conditions (1). This differential toxicity appeared to be related to the change in blood pH induced by each salt. The normal blood pH (7.4) is close enough to the pKbh of ammonia,2 approximately 8.90 at 370 C. (2), so that any change in blood pH would significantly...

Protein-free filtrates of blood treated with trichioracetic acid were divided into two or three parts. The ammonia concentration of one of these was determined immediately by the ninhydrin method described by Nathan and Rodkey (1). The others were kept frozen for periods of 1-8 days and then thawed and analyzed. The blood ammonia concentrations calculated from these filtrate values were compare...

In 1925 Luck, Thacker and Marrack reported elevated blood ammonia levels in epileptic patients after grand mal seizures.1' Although they suspected that muscular exercise might be responsible for this rise, they apparently excluded this possibility by their inability to produce increased venous ammonia levels by vigorous muscular exercise. Several years later Parnas and his co-workers noted that...