Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 19 de 19
Filter
Add more filters










Publication year range
1.
Data Brief ; 48: 109110, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37122925

ABSTRACT

This work presents constitutive equations and a dataset of a thermal model for the prediction of temperature fields and heating rates during the application of localized laser treatments to a Fe-C-Ni alloy. The model considers transient material properties and the coupling between temperature and microstructure, with emphasis on the phase dependence of the thermal parameters and the hysteresis in the phase change. The model can predict temperature fields that are in agreement with the experimental microstructures at the laser-affected zones. This model can be applied to other materials exhibiting solid-state transformations upon the application of laser treatments.

2.
Eur J Clin Invest ; 33(7): 589-94, 2003 Jul.
Article in English | MEDLINE | ID: mdl-12814396

ABSTRACT

BACKGROUND: It is unclear whether cortisol production and the 11betaHSD-mediated cortisol to cortisone interconversion are different between type 1 diabetic patients and healthy subjects. MATERIALS AND METHODS: Fourteen male, nonobese, normotensive type 1 diabetic patients without severe complications (HbA1c < 8.5%) were studied twice during a daily sodium intake of 50 and 200 mmol, and were then compared with 14 individually matched healthy subjects. Cortisol production was assessed by the sum of urinary cortisol metabolite excretion. Urinary ratios of (tetrahydrocortisol + allo-tetrahydrocortisol)/tetrahydro-cortisone [(THF + allo-THF)/THE] and of free cortisol/free cortisone [UFF/UFE] were determined as parameters of 11betaHSD activity. RESULTS: Sum of urinary cortisol metabolite excretion during low- and high-salt diet was 7.4 +/- 2.5 vs. 7.7 +/- 2.3 nmol min-1 m-2 (NS) in diabetic patients and 9.7 +/- 2.1 vs. 11.2 +/- 4.1 nmol min-1 m-2 (NS) in healthy subjects, respectively (P < 0.05 vs. healthy subjects at both diets). The allo-THF excretion and allo-THF/THF ratios were lower in the diabetic than in the healthy males during both diets (P < 0.05). Urinary (THF + alloTHF)/THE and UFF/UFE were similar in both groups and remained unchanged after salt loading. CONCLUSIONS: The sum of urinary cortisol metabolite excretion as a measure of cortisol production is lower in nonobese, normotensive type 1 diabetic males with adequate glycaemic control and without severe complications, irrespective of sodium intake. We suggest that this is at least in part as result of diminished 5alpha reductase activity, resulting in a decreased cortisol metabolic clearance. In type 1 diabetic and in healthy males, the 11betaHSD setpoint is not affected by physiological variations in sodium intake.


Subject(s)
Blood Glucose/metabolism , Diabetes Mellitus, Type 1/metabolism , Hydrocortisone/metabolism , Hydroxysteroid Dehydrogenases/metabolism , 11-beta-Hydroxysteroid Dehydrogenases , Adult , Body Mass Index , Diabetes Mellitus, Type 1/urine , Dose-Response Relationship, Drug , Humans , Hydrocortisone/urine , Hydroxysteroid Dehydrogenases/urine , Male , Sodium Chloride, Dietary/administration & dosage
3.
Eur J Biochem ; 268(14): 3890-7, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11453981

ABSTRACT

Phylogenetic analyses of secretory ribonucleases or RNases 1 have shown that gene duplication events, giving rise to three paralogous genes (pancreatic, seminal and brain RNase), occurred during the evolution of ancestral ruminants. A higher number of paralogous sequences are present in chevrotain (Tragulus javanicus), the earliest diverged taxon within the ruminants. Two pancreatic RNase sequences were identified, one encoding the pancreatic enzyme, the other encoding a pseudogene. The identity of the pancreatic enzyme was confirmed by isolation of the protein and N-terminal sequence analysis. It is the most acidic pancreatic ribonuclease identified so far. Formation of the mature enzyme requires cleavage by signal peptidase of a peptide bond between two glutamic acid residues. The seminal-type RNase gene shows features of a pseudogene, like orthologous genes in other ruminants investigated with the exception of the bovine species. The brain-type RNase gene of chevrotain is expressed in brain tissue. A hybrid gene with a pancreatic-type N-terminal and a brain-type C-terminal sequence has been identified but nothing is known about its expression. Phylogenetic analysis of RNase 1 sequences of six ruminant, three other artiodactyl and two whale species support previous findings that two gene duplications occurred in a ruminant ancestor. Three distinct groups of pancreatic, seminal-type and brain-type RNases have been identified and within each group the chevrotain sequence it the first to diverge. In taxa with duplications of the RNase gene (ruminants and camels) the gene evolved at twice as fast than in taxa in which only one gene could be demonstrated; in ruminants there was an approximately fourfold increase directly after the duplications and then a slowing in evolutionary rate.


Subject(s)
Ribonucleases/genetics , Ribonucleases/metabolism , Ruminants/genetics , Animals , Artiodactyla/genetics , Base Sequence , Brain/enzymology , Evolution, Molecular , Male , Molecular Sequence Data , Pancreas/enzymology , Phylogeny , Ribonuclease, Pancreatic/genetics , Ribonuclease, Pancreatic/metabolism , Ribonucleases/classification , Semen/enzymology , Sequence Homology, Nucleic Acid
4.
Biochim Biophys Acta ; 1547(1): 95-103, 2001 May 05.
Article in English | MEDLINE | ID: mdl-11343795

ABSTRACT

Molecular evolutionary analyses of mammalian ribonucleases have shown that gene duplication events giving rise to three paralogous genes occurred in ruminant ancestors. One of these genes encodes a ribonuclease identified in bovine brain. A peculiar feature of this enzyme and orthologous sequences in other ruminants are C-terminal extensions consisting of 17-27 amino acid residues. Evidence was obtained by Western blot analysis for the presence of brain-type ribonucleases in brain tissue not only of ox, but also of sheep, roe deer and chevrotain (Tragulus javanicus), a member of the earliest diverged taxon of the ruminants. The C-terminal extension of brain-type ribonuclease from giraffe deviates much in sequence from orthologues in other ruminants, due to a change of reading frame. However, the gene encodes a functional enzyme, which could be expressed in heterologous systems. The messenger RNA of bovine brain ribonuclease is not only expressed at a high level in brain tissue but also in lactating mammary gland. The enzyme was isolated and identified from this latter tissue, but was not present in bovine milk, although pancreatic ribonucleases A and B could be isolated from both sources. This suggests different ways of secretion of the two enzyme types, possibly related to structural differences. The sequence of the brain-type RNase from chevrotain suggests that the C-terminal extensions of ruminant brain-type ribonucleases originate from deletions in the ancestral DNA (including a region with stop codons), followed by insertion of a 5-8-fold repeated hexanucleotide sequence, coding for a proline-rich polypeptide.


Subject(s)
Brain/enzymology , Ribonucleases/metabolism , Ruminants/metabolism , Amino Acid Sequence , Animals , Base Sequence , Cattle , Deer , Electrophoresis, Polyacrylamide Gel , Escherichia coli/metabolism , Evolution, Molecular , Female , Gene Duplication , Genetic Vectors , Male , Mammary Glands, Animal/enzymology , Molecular Sequence Data , RNA, Messenger/metabolism , Ribonucleases/genetics , Ribonucleases/isolation & purification , Sequence Homology , Sheep
5.
J Mol Evol ; 48(3): 360-8, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10093226

ABSTRACT

Mammalian secretory ribonucleases (RNases 1) form a family of extensively studied homologous proteins that were already used for phylogenetic analyses at the protein sequence level previously. In this paper we report the determination of six ribonuclease gene sequences of Artiodactyla and two of Cetacea. These sequences have been used with ruminant homologues in phylogenetic analyses that supported a group including hippopotamus and toothed whales, a group of ruminant pancreatic and brain-type ribonucleases, and a group of tylopod sequences containing the Arabian camel pancreatic ribonuclease gene and Arabian and Bactrian camel and alpaca RNase 1 genes of unknown function. In all analyses the pig was the first diverging artiodactyl. This DNA-based tree is compatible to published trees derived from a number of other genes. The differences to those trees obtained with ribonuclease protein sequences can be explained by the influence of convergence of pancreatic RNases from hippopotamus, camel, and ruminants and by taking into account the information from third codon positions in the DNA-based analyses. The evolution of sequence features of ribonucleases such as the distribution of positively charged amino acids and of potential glycosylation sites is described with regard to increased double-stranded RNA cleavage that is observed in several cetacean and artiodactyl RNases which may have no role in ruminant or ruminant-like digestion.


Subject(s)
Artiodactyla/genetics , Cetacea/genetics , Phylogeny , Ribonuclease, Pancreatic/genetics , Amino Acid Sequence , Animals , Base Sequence , DNA Primers , Molecular Sequence Data , Sequence Homology, Amino Acid , Sequence Homology, Nucleic Acid
6.
Gene ; 212(2): 259-68, 1998 Jun 08.
Article in English | MEDLINE | ID: mdl-9611269

ABSTRACT

Mammalian pancreatic ribonucleases (RNase) form a family of extensively studied homologous proteins. Phylogenetic analyses, based on the primary structures of these enzymes, indicated that the presence of three homologous enzymes (pancreatic, seminal and brain ribonucleases) in the bovine species is due to gene duplication events, which occurred during the evolution of ancestral ruminants. In this paper the sequences are reported of the coding regions of the orthologues of the three bovine secretory ribonucleases in hog deer and roe deer, two deer species belonging to two different subfamilies of the family Cervidae. The sequences of the 3' untranslated regions of the three different secretory RNase genes of these two deer species and giraffe are also presented. Comparison of these and previously determined sequences of ruminant ribonucleases showed that the brain-type enzymes of giraffe and these deer species exhibit variations in their C-terminal extensions. The seminal-type genes of giraffe, hog deer and roe deer show all the features of pseudogenes. Phylogenetic analyses, based on the complete coding regions and parts of the 3' untranslated regions of the three different secretory ribonuclease genes of ox, sheep, giraffe and the two deer species, show that pancreatic, seminal- and brain-type RNases form three separate groups.


Subject(s)
Artiodactyla/genetics , Deer/genetics , Genes , Pseudogenes , Ribonuclease, Pancreatic/genetics , Amino Acid Sequence , Animals , Base Sequence , Brain/enzymology , Cattle , Endoribonucleases/genetics , Molecular Sequence Data , Phylogeny , Sequence Alignment , Sequence Homology, Amino Acid , Sequence Homology, Nucleic Acid , Sheep
7.
J Intern Med ; 239(2): 157-64, 1996 Feb.
Article in English | MEDLINE | ID: mdl-8568484

ABSTRACT

OBJECTIVE: To evaluate the natural course of indolent mastocytosis in adults. DESIGN: A retrospective long-term follow-up study. SETTING: The Department of Endocrinology of a University Hospital. PATIENTS: Sixteen adult patients with a diagnosis of indolent mastocytosis and sufficient biochemical data for statistical analysis. One patient had paediatric-onset cutaneous mastocytosis, whilst the others had adult-onset systemic mastocytosis. Ages at the end of follow-up ranged from 23 to 79, median 50 years. Follow-up periods per patient lasted from 13 to 135 months, median 90 months. MEASUREMENTS: Urinary excretions of the histamine metabolites N tau-methylhistamine (MH) and N tau-methylimidazoleacetic acid (MIMA), and signs and symptoms of the disease. RESULTS: The excretion of MH but not MIMA increased in four patients (ages 37, 45, 61 and 65 years) and decreased in two patients (ages 26 and 48 years), including the only patient with paediatric-onset cutaneous mastocytosis. The excretion of MIMA but not MH increased in none and decreased in one patients (age 51 years). The excretions of both MH and MIMA increased in one patient (age 23 years) and decreased in two patients (ages 65 and 79 years). The excretion of MH and MIMA can be considered to have been stable in one patient (age 49 years). In the five remaining patients, observation periods were rather short. A definite judgement on the course of their disease could not be given. In the two patients in whom the excretion of both MH and MIMA decreased, the enlarged spleen decreased in size, whilst in the other patients, signs and symptoms did not change. There were no accompanying myeloproliferative disorders in any patient. No special treatment aiming at a reduction in mast cell load has been given. Rates of change over the whole follow-up period ranged from -8.4 to +25.1% per year. CONCLUSION: The natural course of indolent adult-onset mastocytosis is not always progressive. Our data show that the activity of adult-onset indolent mastocytosis, as measured by urinary excretion of MH and MIMA and clinical signs and symptoms, can substantially decline, especially in older patients.


Subject(s)
Imidazoles/urine , Mastocytosis/urine , Methylhistamines/urine , Adult , Aged , Bone Marrow Diseases/urine , Female , Follow-Up Studies , Humans , Liver Diseases/urine , Male , Middle Aged , Retrospective Studies , Splenic Diseases/urine
8.
J Mol Evol ; 41(3): 277-83, 1995 Sep.
Article in English | MEDLINE | ID: mdl-7563113

ABSTRACT

The history of the abundant repeat elements in the bovine genome has been studied by comparative hybridization and PCR. The Bov-A and Bov-B SINE elements both emerged just after the divergence of the Camelidae and the true ruminants. A 31-bp subrepeat motif in satellites of the Bovidae species cattle, sheep, and goat is also present in Cervidae (deer) and apparently predates the Bovidae. However, the other components of the bovine satellites were amplified after the divergence of the cattle and the Caprinae (sheep and goat). A 23-bp motif, which as subrepeat of two major satellites occupies 5% of the cattle genome, emerged only after the split of the water buffalo and other cattle species. During the evolution of the Bovidae the satellite repeat units were shaped by recombination events involving subrepeats, other satellite components, and SINE elements. Differences in restriction sites of homologous satellites indicate a continuing rapid horizontal spread of new sequence variants.


Subject(s)
Cattle/genetics , DNA/genetics , Phylogeny , Repetitive Sequences, Nucleic Acid , Animals , Base Sequence , Buffaloes/genetics , Consensus Sequence , Deer/genetics , Goats/genetics , Molecular Sequence Data , Recombination, Genetic , Sequence Homology, Nucleic Acid , Sheep/genetics , Species Specificity
9.
Protein Expr Purif ; 6(4): 472-80, 1995 Aug.
Article in English | MEDLINE | ID: mdl-8527933

ABSTRACT

Bovine pancreatic ribonuclease (RNase A) is a member of a homologous group of extensively studied proteins. It is a small, basic protein, containing 124 amino acid residues and four stabilizing disulfide bridges. Ribonuclease A catalyzes the hydrolysis of the phosphodiester bonds in ribonucleic acids. Since this degradation of RNA interferes with normal cell functions, the signal peptide of alkaline phosphatase (phoA, Escherichia coli) was cloned onto the gene coding for RNase A, directing the protein to the periplasm. Several expression systems have been evaluated which use T7, trc, or PR promoters to transcribe the RNase A gene. Also, variation in host strains was tested to optimize the protein yield. It was found that the PR system gave better expression than the two other systems. E. coli strain BL21 was shown to be the strain in which export to the periplasm was most effective and recombinant RNase A could be isolated from the periplasmic fraction of these cells. The system provides a stable yield of active recombinant bovine pancreatic RNase of about 45-50 mg/liter of cell culture.


Subject(s)
Escherichia coli/genetics , Ribonuclease, Pancreatic/genetics , Amino Acid Sequence , Animals , Base Sequence , Cattle , Chromatography, Ion Exchange , Gene Expression , Genetic Vectors , Molecular Sequence Data , Pancreas/enzymology , Plasmids/genetics , Recombinant Fusion Proteins/biosynthesis , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/isolation & purification , Ribonuclease, Pancreatic/biosynthesis , Ribonuclease, Pancreatic/isolation & purification
10.
J Mol Evol ; 37(1): 29-35, 1993 Jul.
Article in English | MEDLINE | ID: mdl-8360916

ABSTRACT

Mammalian pancreatic ribonucleases form a family of homologous proteins that has been extensively investigated. The primary structures of these enzymes were used to derive phylogenetic trees. These analyses indicate that the presence of three strictly homologous enzymes in the bovine species (the pancreatic, seminal, and cerebral ribonucleases) is due to gene duplication events which occurred during the evolution of ancestral ruminants. In this paper we present evidence that confirms this finding and that suggests an overall structural conservation of the putative ribonuclease genes in ruminant species. We could also demonstrate that the sequences related to ox ribonuclease coding regions present in genomic DNA of the giraffe species are the orthologues of the bovine genes encoding the three ribonucleases mentioned above.


Subject(s)
Cattle/genetics , DNA , Mammals/genetics , Ribonuclease, Pancreatic/genetics , Amino Acid Sequence , Animals , Base Sequence , Cloning, Molecular , Conserved Sequence , Molecular Sequence Data , Multigene Family , Species Specificity
12.
Clin Chim Acta ; 159(3): 229-37, 1986 Sep 30.
Article in English | MEDLINE | ID: mdl-3769211

ABSTRACT

A capillary gas chromatographic method with mass spectrometric detection for the determination of pipecolic acid in urine and plasma (or serum) has been developed. Using a quantification based on stable isotope dilution mass fragmentography the concentration of pipecolic acid was determined in urines of 34 healthy children and 8 patients with Zellweger's syndrome. The urinary pipecolic acid excretion of healthy infants decreases with age. Its concentration in urines of patients with Zellweger's syndrome was not consistently elevated. Normal values for pipecolic acid in plasma were established for 19 healthy children. Pipecolic acid concentrations in 47 urine samples (range 0.02-228.3 mmol/mol of creatinine) and 6 serum samples of Zellweger patients after oral loading with DL-pipecolic acid (range 65-1334 mumol/l) were found to correlate satisfactorily with the results obtained by an amino acid analyzer method. The major advantage of the presented method over the amino acid analyzer method concerns its greater sensitivity and its much shorter analysis time.


Subject(s)
Gas Chromatography-Mass Spectrometry/methods , Pipecolic Acids/urine , Abnormalities, Multiple/blood , Abnormalities, Multiple/urine , Adolescent , Child , Child, Preschool , Deuterium , Humans , Infant , Pipecolic Acids/blood , Reference Values , Syndrome
13.
Agents Actions ; 18(1-2): 269-72, 1986 Apr.
Article in English | MEDLINE | ID: mdl-3728212

ABSTRACT

Both short-term and long-term effects of the beta-sympathomimetic drugs isoprenaline and terbutaline on the urinary excretion of histamine and its two main metabolites were evaluated in patients with systemic mastocytosis. In a short-term study isoprenaline and terbutaline were given intravenously during five hours to three and two patients, respectively. Compared with placebo infusion Nt-methylhistamine excretion fell during terbutaline administration, whereas during isoprenaline no changes were observed. In a long-term study three patients received a treatment with orally administered terbutaline for 24 days. In one patient a slight reduction of the excretion of the histamine metabolites was found. In another patient the excretion of histamine and its metabolites decreased especially during the eight days observation period after the end of the treatment. In this study we saw occasionally large and rapid changes occurring simultaneously in all three urinary parameters of histamine release. In conclusion, terbutaline can reduce histamine release in systemic mastocytosis. However, because of the small symptomatic and biochemical effects found in our patients, the clinical significance of beta-sympathomimetic drug treatment in this disease has yet to be established.


Subject(s)
Histamine/urine , Isoproterenol/pharmacology , Terbutaline/pharmacology , Urticaria Pigmentosa/metabolism , Adult , Aged , Female , Histamine/metabolism , Humans , Male , Middle Aged
14.
Agents Actions ; 16(3-4): 76-9, 1985 Apr.
Article in English | MEDLINE | ID: mdl-2409780

ABSTRACT

N tau-methylhistamine concentrations in plasma and urine were determined using a newly developed simultaneous determination for histamine and N tau-methylhistamine, based on isotope dilution mass fragmentography. Three groups of patients were investigated: patients receiving intravenously-administered iodamide for excretory urography, patients receiving a wasp-sting challenge, and patients treated with an intravenously-administered muscle relaxant. In all patients showing a distinct systemic anaphylactic or anaphylactoid reaction histamine and N tau-methylhistamine concentrations were found to be elevated. From the results of this study it can be concluded that N tau-methylhistamine in plasma and urine is a good parameter for histamine release, and that the determination of this histamine metabolite are less hampered by possible artefacts (due to basophil disrupture, a very short half-life time or bacterial production) than determinations of histamine itself.


Subject(s)
Anaphylaxis/metabolism , Body Fluids/analysis , Histamine Release , Methylhistamines/analysis , Female , Histamine/analysis , Humans , Male , Methylhistamines/blood , Methylhistamines/urine
15.
Agents Actions ; 15(3-4): 189-94, 1984 Oct.
Article in English | MEDLINE | ID: mdl-6524519

ABSTRACT

Urinary excretions of histamine, N tau-methylhistamine and N tau-methylimidazoleacetic acid have been determined in 10 normal subjects on 3 different diets, containing a very low protein, a low protein and a high protein amount. Foodstuffs which could contain histamine were excluded. The mean excretion of N tau-methylhistamine on the second day of each diet amounted to 0.861 mumol/24 h, 1.051 mumol/24 h and 1.378 mumol/24 h, respectively. The excretions of histamine and N tau-methylimidazoleacetic acid were not affected. In 6 normal persons on a protein low diet, the excretions of histamine, N tau-methylhistamine and N tau-methylimidazoleacetic acid have been determined for 10 days. On the fifth day, to 3 persons 200 mumol of histamine was given orally, the other 3 persons received a high protein diet. The persons receiving histamine showed a strongly enhanced excretion of N tau-methylimidazoleacetic acid, corresponding to 36.1% of the administered histamine, whereas the urinary excretions of histamine and N tau-methylhistamine were only slightly elevated. On the high protein diet, only the excretion of N tau-methylhistamine was slightly elevated. The urinary excretions of histamine in the female subjects sometimes showed unexpectedly high values. Most probably, this phenomenon is attributable to bacterial histamine production in the urogenital tract.


Subject(s)
Diet , Histamine/urine , Acetates/urine , Adult , Dietary Proteins/administration & dosage , Female , Humans , Imidazoles/urine , Male , Methylhistamines/urine , Middle Aged , Urea/urine
16.
Anal Biochem ; 139(2): 474-81, 1984 Jun.
Article in English | MEDLINE | ID: mdl-6383120

ABSTRACT

A new method for the determination of histamine by stable isotope dilution mass fragmentography is described. The method is specific, sensitive, and accurate, resulting in a within-day coefficient of variation of 4.1% and a day-to-day variation of 7.9%. It was shown that the first blood sample after a venipuncture can contain an artificially elevated plasma histamine concentration. Platelets contain about 7 pmol histamine/10(9) cells. Serum histamine was elevated about four times in comparison with plasma histamine. This phenomenon was mainly ascribed to degranulation of basophilic leukocytes by complement activation during blood clotting. Normal values for plasma histamine were (n = 25) 2.07 +/- 0.75 nmol/liter (mean +/- 1 SD), which is one of the lowest values reported up to now.


Subject(s)
Histamine/blood , Adult , Blood Specimen Collection , Chromatography, Gel , Complement C3/analysis , Complement C4/analysis , Gas Chromatography-Mass Spectrometry , Humans , Indicator Dilution Techniques , Middle Aged , Reference Values , Solvents , Urticaria Pigmentosa/blood
17.
Biomed Mass Spectrom ; 10(8): 480-4, 1983 Aug.
Article in English | MEDLINE | ID: mdl-6616024

ABSTRACT

A determination of histamine in urine by selected ion monitoring, using (15N2)histamine as internal standard, is described. Three different ionization methods were used, chemical ionization with ammonia as reactant gas offering the highest sensitivity (detection limit 40 fmol of histamine on column). The 24 h urinary excretions of 10 normal adults ranged from 142-1100 nmol (mean 321 nmol). Patients with an anaphylactoid reaction and patients with mastocytosis showed above normal values.


Subject(s)
Histamine/urine , Gas Chromatography-Mass Spectrometry/methods , Humans , Mass Spectrometry/methods
18.
J Chromatogr ; 275(2): 261-9, 1983 Jul 08.
Article in English | MEDLINE | ID: mdl-6352721

ABSTRACT

The determination of N tau-methylhistamine in urine, using gas chromatography with nitrogen-phosphorus detection and the homologue N tau-ethylhistamine as internal standard, is described. A comparison between the present method and a previously described stable isotope dilution mass fragmentographic method resulted in a regression line of Y = 0.023 + 0.944X mumol/l with a correlation coefficient of 0.996. The 24-h excretions of 35 normal adults on a free diet ranged from 0.4 to 1.8 mumol. Patients with mastocytosis, chronic myelocytic leukemia, anaphylactic reactions and a patient after bronchial provocation showed above normal values.


Subject(s)
Histamine/metabolism , Methylhistamines/urine , Anaphylaxis/urine , Chromatography, Gas , Gas Chromatography-Mass Spectrometry , Humans , Indicator Dilution Techniques , Leukemia, Myeloid/urine , Urticaria Pigmentosa/urine
19.
Clin Chim Acta ; 121(3): 379-87, 1982 Jun 03.
Article in English | MEDLINE | ID: mdl-6955073

ABSTRACT

N tau-Methylimidazoleacetic acid, the quantitatively most important metabolite of histamine, was isolated from urine by ion exchange chromatography. After esterification with 2-propanol and extraction, N tao-methylimidazoleacetic acid was analyzed by capillary gas chromatography with nitrogen-phosphorus detection, using N tao-ethylimidazoleacetic acid as internal standard. The synthesis of this internal standard is described. In contrast to the methods hitherto described, this method is appropriate for use in clinical chemical laboratories. Normal 24-h excretion ranged from 8.3 to 18.5 mumol (n = 20). Five patients with mastocytosis, a patient with chronic myelocytic leukemia and a patient after an anaphylactoid reaction on acetylsalicylic acid showed highly elevated values.


Subject(s)
Chromatography, Gas/methods , Imidazoles/urine , 1-Propanol , Adult , Anaphylaxis/urine , Chromatography, Ion Exchange , Esterification , Histamine/metabolism , Humans , Hydrogen-Ion Concentration , Leukemia, Myeloid/urine , Nitrogen/analysis , Phosphorus/analysis , Urticaria Pigmentosa/urine
SELECTION OF CITATIONS
SEARCH DETAIL
...