Ammonia in mainstream smoke is present in both the particulate and vapor phases. The presence of ammonia in the cigarette filler material and smoke is of significance because of the potential role ammonia could have in raising the "smoke pH." An increased smoke pH could shift a fraction of total nicotine to free-base nicotine, which is reportedly more rapidly absorbed by the smoker. Methods mea...

The estimation of ammonia in the blood is a difficult matter not. only because ammonia is present in very minute quantities, but also because it is rapidly split off from some labile components of shed blood. The removal of the ammonia by means of an air current is subject to a source of error in as much as the amount of ammonia recovered may vary with the rapid&y of the aeration and the temper...

Nitrosomonas europaea, an obligate ammonia-oxidizing bacterium, lost an increasing amount of ammonia oxidation activity upon exposure to increasing concentrations of nitrite, the primary product of ammonia-oxidizing metabolism. The loss of activity was specific to the ammonia monooxygenase (AMO) enzyme, as confirmed by a decreased rate of NH4+-dependent O2 consumption, some loss of active AMO m...

The conventional method for synthesizing ammonia is a power-hungry process that requires high operating temperatures (400–500 °C) in addition to elevated pressures (150–300 bar). reaction normally catalyzed by magnetite-based particles, and occurs between single mole of nitrogen three moles hydrogen form two ammonia. original Haber–Bosch was developed patented 1916 Fritz Haber Carl Bosch. Since...

The intermediate role of hydroxylamine in nitrate assimilation has been suggested by observations that different organisms form ammonia from hydroxylamine in vivo, and that hydroxylamine occurs in nutrient media and cells. In further support are recent investigations describing enzymatic preparations which catalyze the reduction of hydroxylamine to ammonia. Taniguchi et al. (J. Biochem. (Japan)...

Recent experimental evidence from rainbow trout suggests that gill ammonia transport may be mediated in part via Rhesus (Rh) glycoproteins. In this study we analyzed the transport properties of trout Rh proteins (Rhag, Rhbg1, Rhbg2, Rhcg1, Rhcg2, Rh30-like) expressed in Xenopus oocytes, using the radiolabeled ammonia analogue [(14)C]methylamine, and the scanning ion electrode technique (SIET). ...

Renal nitrogen metabolism primarily involves urea and ammonia metabolism, and is essential to normal health. Urea is the largest circulating pool of nitrogen, excluding nitrogen in circulating proteins, and its production changes in parallel to the degradation of dietary and endogenous proteins. In addition to serving as a way to excrete nitrogen, urea transport, mediated through specific urea ...

The ability to emit and receive signals over long distances is one of the characteristic attributes of multicellular organisms. Such communication can be mediated in different manners (by chemical compounds, light waves, acoustic waves etc.) and usually is reflected in the behaviour of the communicating organisms. Recently, we reported that individual yeast colonies, organised multicellular str...

background and aims: considering difficulties in usual laboratory methods in detection of viral infections, improved dna-based diagnostic techniques are more reliable. loop mediated isothermal amplification method (lamp) is a nucleic acid amplification method that amplifies dna using six primers which has been developed to diagnose viruses as a rapid and high efficiency test. in this study, the...

Ammonia is implicated as a neurotoxin in brain metabolic disorders associated with hyperammonemia. Acute ammonia toxicity can be mediated by an excitotoxic mechanism, oxidative stress and nitric oxide (NO) production. Astrocytes interact with neurons, providing metabolic support and protecting against oxidative stress and excitotoxicity. Astrocytes also convert excess ammonia and glutamate into...