l-Glutamate uptake, thiourea uptake, and methylammonium uptake and the intracellular ammonium concentration were measured in wild-type and mutant cells of Aspergillus nidulans held in various concentrations of ammonium and urea. The levels of l-glutamate uptake, thiourea uptake, nitrate reductase, and hypoxanthine dehydrogenase activity are determined by the extracellular ammonium concentration...

animal models for h.pylori infection have been developed to clarify the pathogenesis, testing new therapies and developing vaccines against human h.pylori infection. although rats have been used extensively for gastric ulceration and acid secretion studies, the animal is not normally infected with h.pylori.several chemicals such as ethanol and ammonium hydroxide can induce gastric erosion and i...

Ammonium and nitrate are the prevalent nitrogen sources for growth and development of higher plants. 15N-uptake studies demonstrated that ammonium is preferred up to 20-fold over nitrate by Arabidopsis plants. To study the regulation and complex kinetics of ammonium uptake, we isolated two new ammonium transporter (AMT) genes and showed that they functionally complemented an ammonium uptake-def...

T WO levels of ammonium chloride or of ammonium sulfate were added to the rations of commercial feeder cattle. The rations were made isonitrogenous, essentially isocaloric and to contain the same level of calcium, phosphorus and salt. Total gains were essentially the same for all lots, varying only 15.6 lb (7.1 kg) over a 112 day feeding period. Feed conversion was increased only on the ration ...

in this study the effect of nitrogen form and different oxygen levels on growth and development and macronutrients concentrations in lettuce plants was investigated. this investigation showed that sole ammonium application caused fresh and dry weight reduction of shoot and root in lettuce plant. but different oxygen levels had no effect on them. nitrogen concentration of shoot was higher in amm...

Voltage-clamp studies on intact and internally perfused squid giant axons demonstrate that ammonium can substitute partially for either sodium or potassium. Ammonium carries the early transient current with 0.3 times the permeability of sodium and it carries the delayed current with 0.3 times the potassium permeability. The conductance changes observed in voltage clamp show approximately the sa...

One of the challenges to be confronted during landfill operations is to handle the landfill leachate with high ammonium content. Current biological ammonium removal processes either are complicated and hard to manage, or require major investments. Low cost and low maintenance onsite systems for the treatment of landfill leachate with high ammonium content are in urgent need, especially for land...

Increased ammonium (NH(4)(+)/NH(3)) in the brain is a significant factor in the pathophysiology of hepatic encephalopathy, which involves altered glutamatergic neurotransmission. In glial cell cultures and brain slices, glutamate uptake either decreases or increases following acute ammonium exposure but the factors responsible for the opposing effects are unknown. Excitatory amino acid transpor...