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PubMed1999

Exertional myalgia syndrome associated with diminished serum ammonia elevation in ischemic exercise testing.

A 36-year-old man with chronic severe exertional myalgias had a normal serum lactate elevation and diminished serum ammonia elevation on an ischemic forearm exercise test (IFET). The IFET is commonly performed in the evaluation of patients with complaints of exertional myalgias, cramps, and rhabdomyolysis. The finding of a normal serum lactate elevation and a diminished serum ammonia elevation after ischemic exercise is usually considered indicative of myoadenylate deaminase deficiency. However, myoadenylate deaminase activity was normal in this man's muscle biopsy specimen. This case suggests that a diminished serum ammonia elevation in the IFET is not always indicative of myoadenylate deaminase deficiency, a disorder of ammonia production. A diminished serum ammonia elevation in the IFET could also reflect an impairment of net ammonia efflux from muscle into blood.

AMP Deaminase↗

PubMed1999

Effect of aerial ammonia on porcine infection of the respiratory tract with toxigenic Pasteurella multocida.

The objective of the experimental study was to examine whether aerial ammonia alone could predispose the respiratory system of pigs to infection with toxigenic Pasteurella multocida type A. Two groups of 5 pigs each were continuously exposed to 50 ppm ammonia and less than 5 ppm ammonia, respectively, for a 59-day period (from 37 kg to 90 kg bodyweight) followed by necropsy. In an aerosol chamber all pigs were exposed to an aerosol of toxigenic P. multocida type A (mean bacterial concentration in the aerosol-exposure chamber: 10(5) colony forming units/m3; exposure period: 25 min) at day 10, 21, 35 and 49 after the onset of ammonia exposure. During the experiment none of the pigs showed clinical signs of pneumonia nor did they develop visible distortion of the snout. None of the pigs had gross lesions in the lungs at necropsy and toxigenic P. multocida was not detected by culture from the lungs from any of the pigs. The chance of recovering toxigenic P. multocida from nasal swabs (collected during experiment) was 2-4 times greater in the test group compared to the control group. The average daily weight gain was lower for the ammonia exposed pigs compared to the control group. In conclusion the results from this study suggest that ammonia in concentrations of 50 ppm is unlikely to predispose growing pigs to pulmonary infection with toxigenic P. multocida.

Aerosols↗

PubMedDate not supplied

Anhydrous ammonia burns: case presentation and literature review.

Anhydrous ammonia, a caustic compound commonly used in industry, can cause severe burns, even with brief contact. As with other alkali burns, early irrigation to remove the ammonia from burned areas is crucial to limit tissue damage. Two cases of identical exposure to industrial strength ammonia are presented. Each patient was exposed to ammonia liquid and vapors simultaneously when a tank containing this compound exploded. One patient showered at the scene immediately after exposure, whereas the other deferred irrigation until he arrived at the hospital. The first patient suffered minor burns with a 2-day, uncomplicated hospital stay. The second patient suffered 14% total body surface area burns and a significant inhalation injury. He required intubation, mechanical ventilation, and skin grafting during his 13-day hospitalization. Although much is written about the management of chemical burns, few articles address ammonia burns. Aggressive initial management significantly reduces morbidity of ammonia burns.

Adult↗

PubMedDate not supplied

Determination of volatile bases in seafood using the ammonia ion selective electrode: collaborative study.

Nine collaborating laboratories tested a combination of 23 seafood samples for volatile bases using an ammonia ion selective electrode. Results were reported as mg NH3/100 g fish, but the method reflected levels of both ammonia and trimethylamine, which permeated the ammonia membrane. The 23 samples were broken down into 8 blind duplicate pairs, 2 Youden matched pairs, and 3 single samples covering fresh to spoiled product ranging from 8 to 82 mg NH3/100 g. Seven species were evaluated: Atlantic cod, squid, Atlantic halibut, gray sole, monkfish, dogfish, and Atlantic mackerel. The ammonia electrode assay was performed on an aqueous homogenate consisting of 95 mL distilled water and 5.0 g sample tissue. Alkaline ion strength adjusting solution (2 mL) was added to the homogenate to liberate ammonia that was sensed by the ion specific electrode and measured on a precalibrated portable meter. Repeatability standard deviations (RSDr) ranged from 4.2 to 17%; reproducibility standard deviations (RSDR) ranged from 8.8 to 21%. A standard ammonium chloride solution was provided to all laboratories to spike 3 different samples at 10 mg NH3/100 g. Recoveries of added ammonia as ammonium chloride for fresh, borderline, and spoiled samples were 88.6, 107, and 128%, respectively.

Ammonia↗

PubMed2001

Comparison of odour emissions from animal housing systems with low ammonia emission.

Nuisance from livestock facilities is an increasing problem in densely populated areas like The Netherlands. It is in the interest of both farmers and society that housing systems and management methods are developed to minimise the emission of odour. An odour research programme has been completed in The Netherlands to investigate odour emission from both conventional housing systems and systems designed for low ammonia emission. The aim of this paper is to compare within each animal category the odour emission of a number of swine housing systems and poultry housing systems. Emission measurements including 17 housing systems were carried out at 24 livestock facilities. Results showed that investigated systems with low ammonia emission for fattening pigs and sows were significantly (p<0.025) lower than conventional systems, being 50%, or more, lower. For laying hens and broilers, housing systems with low ammonia emission showed odour emissions that in most cases only differed slightly from conventional systems. Correlations between ammonia and odour concentration (within facilities) did not show a consistent pattern. It is concluded that methods for restriction of emitting (slurry) surface in pig husbandry may reduce both ammonia and odour emission. In poultry housings the effects of methods for ammonia reduction that involve drying of fresh manure or litter cannot be directly extrapolated to odour emision.

Air Pollutants↗

PubMed2001

Use of Ulva lactuca to identify ammonia toxicity in marine and estuarine sediments.

Toxicity identification evaluation (TIE) methods are being developed for use with whole sediments. Although a phase I TIE method has been developed to characterize ammonia toxicity in aqueous samples using the marine macroalga Ulva lactuca, the relationship between amphipod and mysid mortality and uptake by U. lactuca of bedded sediment ammonia had not been explored. Additionally, it was not known how interactions in whole sediments between metal and organic contaminants with U. lactuca and ammonia would affect TIE interpretation. The current study showed that ammonia toxicity to amphipods and mysids was reduced significantly in marine sediments in the presence of U. lactuca. The alga slightly affected metal concentrations but did not alter the concentration of organic contaminants in either overlying or interstitial waters. Conversely, ammonia uptake by U. lactuca was not affected by the presence of metal or organic contaminants in the sediments. When used with other TIE manipulations, U. lactuca can be utilized in a whole-sediment, phase I TIE to remove toxicity due to ammonia.

Ammonia↗

PubMed2002

Real-time monitoring of ammonia-oxidizing activity in a nitrifying biofilm by amoA mRNA analysis.

Ammonia monooxygenase encoding mRNA (amoA mRNA) transcription in the wastewater treatment process was investigated using reverse transcription PCR (RT-PCR) as the model indicating specific function and activity in nitrifying processes. The dynamic response of amoA mRNA transcription and ammonia-oxidizing activity to the change of environmental conditions such as pH and concentration of ammonia was examined to determine the inductive factor and the inhibitor for amoA mRNA expression. Furthermore, we semiquantitatively investigated the response of amoA mRNA transcription to the pH fluctuation in a continuous fed nitrifying reactor. As a result, amoA mRNA oriented analysis enabled real-time assay of ammonia-oxidizing activity within 2 h as a response time. In contrast, rRNA and amoA encoding DNA were constantly detected at almost the same amount throughout the experiment. mRNA transcription was regulated by the many environmental conditions: ammonia seems to be one of the strong inducers for transcription of amoA mRNA, whereas low pH seems to be a strong inhibitor. These factors simultaneously affected the mRNA transcription and enzymatic activity leading to the complex phenomena of ammonia-oxidizing activity and amoA mRNA transcription in the continuous feeding reactors.

Ammonia↗

PubMed2003

Nitrification of high strength ammonia wastewater and nitrite accumulation characteristics.

Biological nitrogen removal via the nitrite pathway in wastewater treatment is very important in saving the cost of aeration and as an electron donor for denitrification. Wastewater nitrification and nitrite accumulation were carried out in a biofilm airlift reactor with autotrophic nitrifying biofilm. The biofilm reactor showed almost complete nitrification and most of the oxidized ammonium was present as nitrite at the ammonium load of 1.5 to 3.5 kg N/m3 x d. Nitrite accumulation was stably achieved by the selective inhibition of nitrite oxidizers with free ammonia and dissolved oxygen limitation. Stable 100% conversion to nitrite could also be achieved even under the absence of free ammonia inhibition on nitrite oxidizers. Batch ammonium oxidation and nitrite oxidation with nitrite accumulating nitrifying biofilm showed that nitrite oxidation was completely inhibited when free ammonia is higher than 0.2 mg N/L. However, nitrite oxidation activity was recovered as soon as the free ammonia concentration was below the threshold level when dissolved oxygen concentration was not the limiting factor. Fluorescence in situ hybridization analysis of cryosectioned nitrite accumulating nitrifying biofilm showed that the beta-subclass of Proteobacteria, where ammonia oxidizers belong, was distributed outside the biofilm whereas the alpha-subclass of Proteobacteria, where nitrite oxidizers belong, was found mainly in the inner part of the biofilm. It is likely that dissolved oxygen deficiency or limitation in the inner part of the nitrifying biofilm, where nitrite oxidizers exist, is responsible for the complete shut down of the nitrite oxidizers activity under the absence of free ammonia inhibition.

Ammonia↗

PubMed2003

[Detection of myocardial lesion in patients with acute ammonia poisoning].

OBJECTIVE: To find a better index for detecting myocardial lesion in patients with acute ammonia poisoning. METHODS: Cardiac troponin T (cTnT), creatine kinase (CK), creatine kinase-MB isoenzyme (CK-MB), and electrocardiogram (ECG) were determined and compared in patients with acute ammonia poisoning and healthy controls. RESULTS: In severe ammonia poisoning patients, the levels of cTnT [(1.285 +/- 2.650) micro g/L], CK [(257.636 +/- 362.719) IU/L], CK-MB [(20.909 +/- 19.770) IU/L] were significantly higher than those in healthy control [(0.035 +/- 0.014) micro g/L, (82.050 +/- 36.302) IU/L, (8.350 +/- 2.455) IU/L respectively, P < 0.05]. The levels of cTnT, CK and CK-MB in mild ammonia poisoning patients [(0.039 +/- 0.016) micro g/L, (78.200 +/- 28.401) IU/L and (8.467 +/- 2.669) IU/L respectively], and moderate ammonia poisoning patients [(0.054 +/- 0.043) micro g/L, (99.786 +/- 71.941) IU/L and (9.429 +/- 3.857) IU/L were not significantly different from those of healthy controls (P > 0.05)]. cTnT positive detection rate (68.2%) was significantly higher than CK (36.4%), CK-MB (31.2%) and ECG (31.2%) (P < 0.05). CONCLUSION: cTnT is a better index to detect myocardial lesion in severe ammonia poisoning.

Acute Disease↗

PubMed1992

The influence of pCO2 on the rate of ammonia formation in blood.

The influence of the sample pCO2 on the rate of ammonia formation was studied with gas equilibrated blood samples, using different gas mixtures for the equilibration. The rate of increase in plasma ammonia concentration at a mean pCO2 of 62 mm Hg = 8.2 kPa (mean pH = 7.282) was significantly lower than at 36 mm Hg = 4.8 kPa (pH = 7.438). In CO2-depleted blood (pH > 8) ammonia formation was strongly accelerated. This was reversible by readjusting the pH to 7.4 by addition of Tris-HCl solution. In stoppered containers with or without enclosed atmospheric air, a decrease of blood pCO2 or an increase of pH values was not observed during storage over 15 minutes at 0 or 20 degrees C. Although this study confirms that the pCO2 (or rather the pH) is an important analytical influence quantity in the determination of plasma ammonia, strictly anaerobic processing of the blood samples is not necessary; the usual technique of transporting and preprocessing blood samples in partially filled and stoppered containers appears to be adequate. Mainly due to the deamination of intracellular AMP (1), the ammonia1) concentration in blood increases continuously after sampling. Rates of increase in plasma ammonia concentration have recently been investigated thoroughly with blood samples from healthy probands to define the maximum delay between sampling and separation of the blood cells that can be tolerated if the in vivo existing plasma ammonia concentration has to be measured (2). Strictly speaking, the guidelines for handling the blood samples (2) apply to blood stored under anaerobic conditions.(ABSTRACT TRUNCATED AT 250 WORDS)

Ammonia↗

PubMed2004

Lethal effects of elevated pH and ammonia on juveniles of neotropical fish Colosoma macropomum (Pisces, Caracidae).

Ammonia is the main nitrogenous waste material excreted by gills, then is oxided first to nitrite and then to nitrate. The proportion of ionized-un-ionized ammonia depends on pH and temperature, when this variables increase in a solution containing ammonia the equation goes to left, so the proportion of NH3 increases and the solution becomes more toxic. The purpose of this study was to investigate the acute lethal effects of elevated pH and ammonia on tambaqui juveniles. With a constant ammonia concentration of 5.0 mg/l NH3, there was no mortality a pH of 6.0 (control) and 7.0; but was of 10-20% a pH of 8.0 and 100% at 9.0. The lethal effects of elevated pH and un-ionized ammonia should be recognized as a potential factor contributing to the variable success of tambaqui production ponds, but this species is highly resistant in comparison with other freshwater fish.

Age Factors↗

PubMed2005

Dynamic 13N-ammonia PET: a new imaging method to diagnose hypopituitarism.

UNLABELLED: We have developed a new imaging method to evaluate the blood perfusion and ammonia metabolism of the pituitary gland, and we preliminarily assessed its role in the diagnosis of hypopituitarism. METHODS: Six female healthy volunteers (age range, 20-46 y) and 6 female patients (age range, 23-42 y) were enrolled in this study. Dynamic (13)N-NH(3) PET was performed. Time-activity curves for the pituitary gland and internal carotid artery were generated by setting regions of interest on the transverse planes of the pituitary gland. The standardized uptake value of the pituitary gland, the radioactive ratio of pituitary to thalamus (P/T), and the first-pass uptake rate of ammonia in the pituitary gland were calculated. RESULTS: (13)N-Ammonia was extracted rapidly by pituitary tissue in the first 120 s after injection and trapped in pituitary tissue in the healthy volunteers. Three to 20 min after injection, the pituitary gland was clearly seen in the healthy volunteers, and the mean (+/-SD) size of the pituitary gland on (13)N-ammonia PET images was (1.09 +/- 0.17 cm) x (1.08 +/- 0.14 cm) x (1.12 +/- 0.09 cm). However, in patients with hypopituitarism, the first-pass uptake rate of ammonia in the pituitary gland was significantly lower than that in healthy volunteers (0.35 +/- 0.10 vs. 0.75 +/- 0.07). On images of patients, the pituitary gland was absent or could not clearly be found, was small or malformed, and showed significantly lower uptake of (13)N-NH(3) than in healthy volunteers (standardized uptake value, 1.15 +/- 0.34 vs. 3.74 +/- 1.44; P/T, 0.65 +/- 0.23 vs. 1.24 +/- 0.34). CONCLUSION: Dynamic (13)N-ammonia PET can provide information on blood perfusion and metabolism of the pituitary gland and is useful in early monitoring of damage to the pituitary gland and in diagnosing hypopituitarism.

Adult↗

PubMed2004

[Direct fluorophotometric and flow-injection fluorophotometric methods for the determination of trace ammonia].

Direct fluorophotometric and flow-injection fluorophotometric methods for trace ammonia measurement involving the fluorescent reaction of ammonia with o-phthaldlaldehyde (OPA) and 2-mercaptoethanol (ME) producing derivant of iso-indol in alkaline solution are described. Triton X-100 was added to improve the stability of the system. The maximum excitation wavelength is 415 nm, while the maximum emission wavelength is 486 nm. With direct fliuorophotometric method, the calibration curve's regression equation is deltaI = 22.286 + 785.71c(NH3) (microg x mL(-1)) (r = 0. 9995) in the range of ammonia concentration from 0.2 to 1.0 microg x mL(-1), and deltaI = -27.429 + 2 371.4c(NH3) microg x mL(-1)) (r = 0.9965) in the range of ammonia concentration from 0.02 to 0.10 microg x mL(-1). With flow-injection fluorophotometric method, the calibration curve's regression equation is deltaI = 1188c(NH3) (microg x mL(-1)) (r = 0. 9998) in the range of ammonia concentration of ammonia 0-0.7 microg x mL(-1). The mechanism of reaction was also briefly discussed.

Ammonia↗

PubMed2004

[Mitigation effect of several controlled-release N fertilizers on ammonia volatilization and related affecting factors].

By using static absorption and soil column leaching methods, this paper studied the behaviors of several controlled-release N fertilizers in soil under laboratory conditions. The results showed that under the application rate of 450 mg x kg(-1), total ammonia volatilization from three controlled-release fertilizers decreased by 49.7%, 28.0% and 71.2%, respectively, in comparing with common urea. When the application rate was 600 mg x kg(-1), total ammonia volatilization decreased by 34.6%, 12.3%, 69.9%, respectively. Controlled-release fertilizers could markedly reduce total ammonia volatilization from soil and decrease environment pollution via fertilization. The results also indicated that total ammonia volatilization correlated significantly with soil urease activity, pH value and N leaching rate. The correlation coefficient between total ammonia volatilization and accumulated N leaching rate was 0.9533, and that between total ammonia volatilization and soil urease activity and pH value was 0.9533 and 0.9908, respectively.

Ammonia↗

PubMedDate not supplied

[Adaptation of Biomerieux enzymatic UV ammonia on Konelab analysers].

INTRODUCTION: Circulating ammonia in normal patients is relatively low, despite the fact that ammonia is continually produced from endogenous amino acid metabolism. The physiopathological interest of plasmatic ammonia determination lies primarily in its relationships to hepatic insufficiency (cirrhotic or neoplasic), or the diagnosis and the forecast of the Reye's syndrome. OBJECTS: This study describes an evaluation of plasmatic ammonia determination by the UV end point enzymatic method using GLDH on KONELAB(TM) analyzers. METHODS: The glutamate dehydrogenase (GLDH : EC.1.4.1.3) catalyses the reducing amination of alpha-cetoglutarate in the presence of NH(4)(+) and of NADPH, H(+) to form glutamate and NADP(+). The reduction of NADPH,H(+)'s concentration, directly proportional to ammonia rates, is evaluated at 340 nm. All the conditions were met to optimize the method, while covering a satisfying field of measurement. RESULTS AND COMMENTS: The evaluation of the modified method showed a good precision (repeatability: CV < 4 %; interserial reproducibility: CV from 2.01 to 2.93 %; Intraserial reproducibility: CV equal to 0.67%) and a very good accuracy. The field of measurement extends from 27 to 250 micromol/L, with a limit of detection (L(D)) lowered to 0.325 micromol/L. CONCLUSION: The adapted technique is simple, fast, inexpensive and especially automatizable. It is in addition reliable and chiefly more sensitive, adapting particularly to the determination of plasmatic ammonia in urgency as in routine within our laboratory.

Ammonia↗

PubMed2006

[Study of the fluorescent response for optical ammonia sensing film].

The characters of optical sensing films for ammonia were investigated based on a fluorescent indicator aminofluorescein (AF) immobilization. An organically modified silicates (ORMOSILSs) obtained by copolymerizing various proportions of methyltrimethoxysilane (Me-TriMOS) and tetramethoxysilane (TMOS) was applied. Compared with the fluorescent responses of fluorescein and fluorescein carboxylicate, the fluorescent intensity enhancement of AF for ammonia was found to be caused by the reaction of ammonia with the NH2 group on AF. The reaction may cause the reduction of the intermolecular self-quenching of AF, resulting in a fluorescence enhancement of sensing film in NH3 solution. Furthermore, the properties and the ammonia-sensing behavior of the film were investigated. The results presented here emphasized the significance of ormosil as a matrix for dissolved ammonia sensing. The detection limit for ammonia in water was 0.3 microg x mL(-1).

Ammonia↗

PubMed1975

[Role of adenine mono- and dinucleotides in ammonia formation in brain tissue].

The investigations carried out have shown that not only AMP but ADP also undergoes direct deamination in both soluble and mitochondrial fractions of rat brain tissue. Deamination of AMP is stimulated by the addition of ATP and the activity of one of the isoenzymes of AMP-aminohydrolase is markedly enhanced by both yeast and brain hexokinase. Activation by hexokinase is mainly due to its SH groups, through which hexokinase reacts with AMP-aminohydrolase, forming, probably, a protein-protein complex in which AMP aminohydrolase activity is considerably increased. Hexokinase does not affect the deamination of ADP and NAD. Further experiments are needed to find out whether the activation of AMP-aminohydrolase is accomplished by hexokinase itself or by an other protein contaminating it. Deamination of NAD, in contrast to AMP and ADP, takes place only in mitochondria and does not occur in the soluble fraction. In mitochondria besides deamination, AMP and ADP undergo intensive dephosphorylation, while the deamination of NAD is not accompanied by an increase of phosphate, i. e. mitochondria lack enzymes which breakdown NAD to mono nucleotides. Our data indicate that the formation of deamino -NAD from NAD and reamination of deamino-NAD by aspartate to NAD by the formation of intermediary NAD-succinate is of greater importance. The formation of the latter and that of deamino-NAD from NAD as well as the presence of preformed deamino-NAD in mitochondria have been demonstrated by Movsessian. The occurrence of these processes in mitochondria and their role in the formation of ammonia from amino acids is of importance in as much as oxaloacetate formation and its conversion to aspartate, which is necessary for the reamination of deamino-NAD, are localized in mitochondria. The main source of the amino nitrogen of aspartate is known to be glutamate, which incorporates the amino nitrogen of most amino acids. alpha-Keto-glutarate, which is necessary for the synthesis of glutamate, is also formed in mitochondria are the most favourable site for the formation of ammonia from amino acids with the participation of pyridine nucleotides. Of the purine mono and dinucleotides studied deamino-NAD is most effective in the formation of ammonia from amino acids in mitochondria since in contrast to purine mono nucleotides, deamino-NAD and NAD are not dephosphorylated in mitochondria. According to some authors the reamination of IMP by aspartate is of importance in the formation of ammonia from amino acids in brain tissue. In our studies, however, IMP was not effective in the formation of ammonia from aspartate in mitochondrial fractions. IDP was found to be more effective. IMP and IDP may probably participate in the formation of ammonia in the soluble fraction, where nucleotidase activity is considerably low.

AMP Deaminase↗

PubMed1991

The ammonia tolerance test in horses.

Clinically normal horses (n = 8) with ages ranging from 5 to 8 years, were starved for 12 h and their plasma ammonia concentrations were measured. The mean fasting plasma ammonia concentration was 17.8 +/- 3.8 mumol l-1. After dosing ammonium chloride at a dose rate of 0.02 g kg-1, there was a significant increase in plasma ammonia concentration, with a maximum rise after 20 min (P less than 0.05). To investigate the influence of temperature on plasma ammonia concentrations of stored samples, 8 plasma samples were stored at -20 degrees C and 4 degrees C respectively. The plasma ammonia concentrations were measured after 6, 12 and 24 h in each of the stored samples. Plasma ammonia concentrations increased significantly after 12 and 24 h when stored at 4 degrees C (P less than 0.05). When plasma was stored at -20 degrees C there was no significant increase from baseline concentrations during 24h (P greater than 0.05).

Ammonia↗