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T Biegański

Publications and source records attributed to T Biegański.

At least 19 recordsLinked to original sources
PubMed2001

[Clinical application of proton magnetic resonance spectroscopy for differential diagnosis of pediatric posterior fossa tumors].

We report here on a correlation between proton magnetic resonance spectroscopy (MRS) spectra obtained in children with posterior fossa tumors and tumor histology and grading. Twenty-six children (age 1-16) were investigated before surgery by using single-voxel proton MRS. All examination were performed on a 1.5 T MR scanner by using single-voxel (8 cm3) with PRESS sequence (TR 1600 ms, TE 270 ms, NEX 256). Spectra of N-acetylaspartate (NAA), choline containing compounds (Cho), creatine and phosphocreatine (Cr) and lactate (Lac) were evaluated. Absolute concentrations of the metabolites were measured and their ratios were calculated. Correlation between these and tumor histology and grading were then determined. Concentration of Cho and Lac, and Cho/NAA ratio were the major statistically significant parameters for discrimination between benign (WHO grade I and II) and malignant tumors (WHO grade III and IV), in particular between pilocytic astrocytomas and medulloblastomas. Discrimination between individual histological types within malignant and benign tumor groups was not possible. Proton MRS of pediatric posterior fossa tumors seems to be helpful in prediction of tumor grading and histology. Specific character of the examination requires establishing of the individual standards for every MR scanner.

Adolescent↗
PubMed1999

Ebb and flow rickets in a premature infant: the Afghan turban sign.

The pattern of alternating dense and lucent bands, with straight outer edges, at the youngest metaphysis of long bones, the "Afghan turban" sign, occurs when incompletely treated rickets has recurred and been retreated. Recognition of this, and other, rickets patterns allows the radiologist to influence treatment, as described in a very low birth weight infant.

Clavicle↗
PubMed1996

[Alpha-mannosidosis in two siblings].

A rare metabolic disease, alpha-mannosidosis, is described in two siblings. Psychomotoric deficiency, deafness, coarse face and radiological changes in the skeletal system indicated an inherited lysosomal storage disease.

Bone Diseases↗
PubMed1987

Causal relationship between a tumour growth and the changes in histamine metabolism in tissues of sarcoma-bearing rat.

The relationship between malignancy and histamine metabolism in the liver and the small intestine has been examined in sarcoma-bearing Wistar rats two weeks after subcutaneous implantation of a transplantable methylcholanthrene sarcoma Sa1828 and on the 3, 7 and 14th days after tumour extirpation. Two weeks after tumour implantation, the histamine level was increased by 100% and 50% in the liver and the small intestine, respectively. On the 3rd day after extirpation of the tumour the level of histamine had returned to the control values and remained unchanged during the next 10 days. Neither of the histamine catabolizing enzymes, diamine oxidase with a putrescine as a substrate or histamine methyltransferase were influenced by the existing tumour or by its extirpation except on the 14th day where a high increase in diamine oxidase activity was found. Some changes in the distribution of histamine metabolites suggest an involvement of an oxidative pathway of histamine catabolism as well as the aldehyde catabolizing enzymes in tumour development.

Amine Oxidase (Copper-Containing)↗
PubMed1984

N-methyl-N-formylhydrazine: a toxic and mutagenic inhibitor of the intestinal diamine oxidase.

N-methyl-N-formylhydrazine is the first active intermediate of the poison gyromitrin of the mushroom: false morel. This compound is a non-competitive inhibitor of human intestinal diamine oxidase (ID50 = 1.6 X 10(-5) mol/l). This concentration corresponds to less than 5 g of wet weight of mushroom/l. The diamine oxidases from 5 other sources are inhibited in a similar manner. Semicarbazide and aminoguanidine are 10-respectively 1000-fold more potent inhibitors of the human intestinal diamine oxidase. An involvement of the diamine oxidase inhibitory property of N-methyl-N-formylhydrazine in toxic and mutagenic effects of the substance is considered.

Amine Oxidase (Copper-Containing)↗
PubMed1983

Distribution and properties of human intestinal diamine oxidase and its relevance for the histamine catabolism.

High activities of diamine oxidase (EC 1.4.3.6) were measured in the intestinal tract of human subjects and of several mammalian species. The enzyme was localized in the mucosa and was distributed primarily in the cytoplasm; the only exception being the guinea-pig where it was located in the particulate fraction. Despite its instability the enzyme from human colonic mucosa was purified 80-fold. During the purification a soluble monoamine oxidase (EC 1.4.3.4) was separated from diamine oxidase. The pH optima of diamine oxidase for putrescine and histamine were 6.6-7.0 and 6.4-6.6, respectively. Short-chain aliphatic diamines were deaminated with the highest reaction velocity, but histamine and N tau-methylhistamine were also excellent substrates. The Km for putrescine was 8.3 x 10(-5) M, for histamine 1.9 x 10(-5) M and for N tau-methylhistamine 9.7 x 10(-5) M. Typical substrates of monoamine oxidase were not deaminated by the enzyme. Aminoguanidine strongly inhibited human intestinal diamine oxidase (IC50 = 1.1 x 10(-8) M). Because of its properties the intestinal diamine oxidase is considered to play a protective role against histamine in diseases such as ischaemic bowel syndrome, mesenteric infarction and ulcerative colitis.

Adult↗
PubMed1983

Diamine oxidase in the hen.

In adult hens diamine oxidase (histaminase) activity was found in gastrointestinal tract (with the highest value in ileum), liver and spleen. Intestinal diamine oxidase is predominantly a particle-bound enzyme. In the intestine oxidation of putrescine leads to delta 1-pyrroline formation, in liver both delta 1-pyrroline and gamma-aminobutyric acid are formed. The inhibitor properties of hen intestinal and rat intestinal diamine oxidases are very similar and differ from pea seedling diamine oxidase. The natural dipeptides carnosine and anserine are relatively potent inhibitors of hen intestinal diamine oxidase.

Amine Oxidase (Copper-Containing)↗
PubMed1982

Inhibition of plant and mammalian diamine oxidase by substrate analogues.

Imidazoles, aliphatic substrate analogues and the natural dipeptides, carnosine and anserine, were investigated as inhibitors of diamine oxidase from the pig kidney, human pregnancy plasma and pea seedlings. Imidazole, methylimidazoles, N-acetylimidazole, histamine and N tau-methylhistamine are relatively potent inhibitors of mammalian diamine oxidase showing no influence on plant enzymes. Anserine and carnosine are inhibitors of pig kidney and pea seedling enzymes. Ki values are 2 microM and 10 microM respectively. Investigated natural derivatives of putrescine and cadaverine have no influence on diamine oxidase of different origin. In conclusion, we present some evidence to suggest that mammalian diamine oxidase, despite a high reaction rate with putrescine, is better adapted to histamine oxidation, whereas for plant enzymes the diamines are preferred substrates.

Amine Oxidase (Copper-Containing)↗
PubMed1982

Diamine oxidase activity and imidazoleacetic acid formation in the foetal and maternal guinea pig liver.

Diamine oxidase activity and imidazoleacetic acid formation in the foetal and maternal guinea pig liver during gestation were examined. DAO activity and IMAA formation in the foetal liver increased continuously, while maternal enzyme activity and ImAA formation in the second half of pregnancy simultaneously decreased. The roles of GABA and ImAA are discussed.

Amine Oxidase (Copper-Containing)↗
PubMed1982

Inhibition of plant and mammalian diamine oxidases by hydrazine and guanidine compounds.

1. Pig kidney and pea seedling diamine oxidases have similar sensitivity to methylhydrazine and phenylhydrazine as inhibitors. 2. Inhibition of pig kidney and pea seedling enzymes by hydrazine and guanidine compounds is time dependent. To reveal full inhibitory potency, methylhydrazine and aminoguanidine need longer preincubation with plant diamine oxidase as compared with mammalian diamine oxidase. 3. Impromidine, a known H2 histamine receptor agonist with guanidine and imidazole structures, and aminoguanidine have higher inhibitory activity towards pig kidney enzyme in comparison with the pea seedling one. 4. Impromidine inhibits pig kidney diamine oxidase in a noncompetitive manner. The Ki value is 6.6 muM. 5. The 24 hr dialysis of rat intestinal diamine oxidase preincubated with phenylhydrazine or impromidine only partially recovered the enzymic activities. 6. Impromidine inhibits mouse intestinal diamine oxidase in vivo.

Amine Oxidase (Copper-Containing)↗
PubMed1982

Gamma-aminobutyric acid (GABA) formation from putrescine in guinea-pig liver during ontogenesis.

1. The changes in hepatic diamine oxidase (DAO) activity of the foetal and maternal origin and their relations to GABA formation during pregnancy in guinea-pigs are described. 2. Foetal DAO activity continuously increased while the maternal enzyme from the 45th day of gestation onwards decreased. 3. Conversion of putrescine to GABA via oxidative deamination has been detected in the earliest studied day i.e. the 34th.

Amine Oxidase (Copper-Containing)↗
PubMed1980

Human intestinal diamine oxidase: substrate specificity and comparative inhibitor study.

For an 80-fold purified preparation of human intestinal diamine oxidase the optimum conditions of incubation, the substrate and the inhibitor specificity were tested. Putrescine was the most favoured substrate but N tau-methylhistamine and 2-methylhistamine were metabolized at optimum conditions with nearly the same velocity. Histamine reached about 50% of the reaction velocity of putrescine. Aminoguanidine and semicarbazide inhibited the human intestinal enzyme like a classical diamine oxidase. However, a distinct inhibition of human intestinal and pea seedling diamine oxidase was observed in presence of beta-aminopropionitrile (weak inhibition of the human enzyme, strong inhibition of pea seedling diamine oxidase) and burimamide (strong inhibition of human intestinal enzyme, nearly no influence on pea seedling diamine oxidase). It is proposed to differentiate on the basis of functional considerations diamine oxidases with more histamine detoxicating activities from those being more involved in regulating polyamine levels in growing tissues.

Amine Oxidase (Copper-Containing)↗
PubMed1980

The influence of carcinoma growth on diamine oxidase activity in human gastrointestinal tract.

The distribution of diamine oxidase (DAO) activity was studied in patients having no carcinoma disease. Besides in gut DAO occurred in high activity only in kidney and mesenteric lymph nodes. In patients with adenocarcinoma of the large bowel or of the stomach the enzymic activity was reduced in the tumour tissue itself as compared with the adjacent mucosa in which part the highest activities were observed. In stomach it seemed most important that the enzymic activity was enhanced in the whole mucosa, also in a 10 cm distance from tumour where no histological alterations were found. This fact should be checked for significance in early tumour diagnosis.

Adenocarcinoma↗
PubMed1980

The importance of human intestinal diamine oxidase in the oxidation of histamine and/or putrescine.

Histamine, naturally methylated histamine and putrescine are good substrates for human intestinal diamine oxidase, N-Methyl-N-formylhydrazine, the constituent of the mashroom poison-gyromitrin is an inhibitor of human intestinal diamine oxidase. Burimamide inhibits more effectively mammalian intestinal diamine oxidases than pea seedling diamine oxidase, beta-aminopropionitrile is a better inhibitor of pea seedling enzyme than mammalian diamine oxidases. This inhibitory differences might be related to preference in histamine or putrescine oxidizing activity of these enzymes.

Amine Oxidase (Copper-Containing)↗
PubMed1980

Oxidative deamination of 14C putrescine in mouse tissues in vivo.

Oxidative deamination of 14C putrescine was examined in vivo in mice. Exogenous putrescine is catabolized rapidly; 2.5 min after i.v. putrescine infection, its main oxidative metabolites, namely GABA and an unidentified compound were detected in all tissues tested; inhibition of DAO activity by aminoguanidine strongly suppressed formation of both products.

Amine Oxidase (Copper-Containing)↗