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L Raimondi

Publications and source records attributed to L Raimondi.

At least 55 records · Page 3Linked to original sources
PubMed1992

Further studies on semicarbazide-sensitive amine oxidase activities (SSAO) of white adipose tissue.

1. White adipose tissue (WAT) from mice, rabbits, pigs and human subjects was investigated for the characterization of the tissue-bound semicarbazide-sensitive benzylamine oxidase activities (SSAO) present in each species. 2. Enzymes from mice, rabbits and pigs shared similar biochemical characteristics: they exerted histaminase activity, oxidized methylamine and acetylputrescine and were completely blocked by carbonyl reagents and by 3,5-ethoxy-4-aminomethylpyridyne (B24), in a dose-dependent fashion. 3. SSAO activity from human WAT had a lower affinity for benzylamine compared with enzymes in the other species and did not show any histaminase activity. 4. These results show that SSAO from human tissues might have different properties from SSAO of other species.

Adipose Tissue↗
PubMed1989

Amino acid sequence of mouse nidogen, a multidomain basement membrane protein with binding activity for laminin, collagen IV and cells.

The whole amino acid sequence of nidogen was deduced from cDNA clones isolated from expression libraries and confirmed to approximately 50% by Edman degradation of peptides. The protein consists of some 1217 amino acid residues and a 28-residue signal peptide. The data support a previously proposed dumb-bell model of nidogen by demonstrating a large N-terminal globular domain (641 residues), five EGF-like repeats constituting the rod-like domain (248 residues) and a smaller C-terminal globule (328 residues). Two more EGF-like repeats interrupt the N-terminal and terminate the C-terminal sequences. Weak sequence homologies (25%) were detected between some regions of nidogen, the LDL receptor, thyroglobulin and the EGF precursor. Nidogen contains two consensus sequences for tyrosine sulfation and for asparagine beta-hydroxylation, two N-linked carbohydrate acceptor sites and, within one of the EGF-like repeats an Arg-Gly-Asp sequence. The latter was shown to be functional in cell attachment to nidogen. Binding sites for laminin and collagen IV are present on the C-terminal globule but not yet precisely localized.

Amino Acid Sequence↗
PubMed1989

Effect of pyridoxamine on semicarbazide-sensitive amine oxidase activity of rabbit lung and heart.

Rabbit lung and heart show clorgyline-resistant benzylamine oxidase activity which is sensitive to semicarbazide (SSAO) and alpha-amino-guanidine. This SSAO activity is inhibited by pyridoxamine with an IC50 of 6.3 x -6 M for lung and of 1.1 x 10(-5) M for heart, the inhibition being non-competitive and only partially reversed by dialysis at 4 degrees C. Semicarbazide, alpha-aminoguanidine and pyridoxamine show a similar time-dependent type of inhibition of rabbit lung and heart SSAO.

Amine Oxidase (Copper-Containing)↗
PubMed1988

Lysosomal enzymes in experimental allergic encephalomyelitis: time course and evidence of the source.

The lysosomal enzymes acid proteinase and beta-glucuronidase, were assayed in spinal cords of rats during the course of experimental allergic encephalomyelitis (EAE). Histological and histochemical examination was carried out versus controls, in selected areas of the same cords biochemically assayed, to look at the distribution of the lysosomal enzyme acid phosphatase. The biochemical assay showed a significant increase of the enzyme activities during the disease and the increase was significantly correlated with the intensity of the disease. The distribution in the nervous tissue of the increase in acid phosphatase activity observed in animals with EAE, suggests that endogenous nervous cells may contribute to the lysosomal enzyme increase in EAE.

Animals↗
PubMed1988

Aspartame and the rat brain monoaminergic system.

A high dose of aspartame (APM) was administered to rats to study possible effects on brain monoaminergic systems. APM and its metabolite phenylalanine (Phe) were given orally at doses of 1000 and 500 mg/kg, respectively. Significant increases were seen in brain Phe and tyrosine (Tyr) levels. Two different approaches were used to study monoaminergic systems: whole tissue measurements by HPLC-ED and in vivo voltammetry in freely moving rats. Dopamine, serotonin and their metabolites were taken as indexes of neuronal activity. In spite of the high dose used, no modification was found in monoamines or their metabolites in striatum, hippocampus and nucleus accumbens.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1988

On the presence of a clorgyline resistant benzylamine oxidase activity in mouse kidney.

In the crude homogenates of three different strains (C3H, Swiss, C57b) of mouse kidney the exposure to a millimolar concentration of clorgyline reveals a benzylamine oxidative deaminating activity that is due to a clorgyline resistant amine oxidase (CRAO). In the three strains this CRAO activity shows a low sensitivity to semicarbazide and to alpha- amiguanidine. In the C3H mouse kidney the glycoprotein nature of the CRAO was established from affinity chromatography with immobilized concanavalin A. Studies of this activity in the C3H mouse kidney revealed the presence of a reversible inhibitor which is precipitated by ammonium sulphate between 35-55% of saturation. The presence of this inhibitor precludes accurate measurement of the CRAO distribution in the different subcellular fractions. The enzyme purified by affinity chromatography, is semicarbazide insensitive. This is the first observation of the presence of a CRAO-semicarbazide insensitive activity in a tissue. The fact that "original homogenate" and the subcellular fractions show some sensitivity to semicarbazide also indicates that a semicarbazide-sensitive amine oxidase (SSAO) is present in the C3H mouse kidney.

Amine Oxidase (Copper-Containing)↗
PubMed1986

Guanabenz as inhibitor of copper-containing amine oxidases.

The effects of guanabenz on some copper containing amine oxidases are described. Guanabenz 'in vitro' inhibits pig plasma benzylamine oxidase with a IC50 M 5.1 +/- 0.8 X 10(-6) M. It also inhibits pig kidney diamine oxidase and rat liver mitochondrial monoamine oxidase at higher concentrations. The significance of this property of guanabenz is discussed.

Amine Oxidase (Copper-Containing)↗
PubMed1986

Pharmacological activity of FPP028 (2-phenylpyrazolo-4-ethyl-4,7-dihydro [1,5a]pyrimidin-7-one) a new non-steroid anti-inflammatory agent.

The activity of 2-phenylpyrazolo-4-ethyl-4,7-dihydro [1,5a]pyrimidin-7-one (FPP028), a non-acidic, analgesic, antipyretic, and anti-inflammatory compound, was investigated in a number of pharmacological tests performed in rats. The anti-inflammatory properties of FPP028 were evaluated through the carrageenan induced paw edema and the cotton pellet induced granuloma and compared with the activity of indomethacin, phenylbutazone, and isoxicam; as a result, the activity of FPP028 was shown to be similar to that of the latter compounds. To assess the analgesic properties of FPP028 in comparison with indomethacin and phenylbutazone, the Randall and Sellitto and the mouse-writhing tests were used; in both tests, FPP028 demonstrated a significant analgesic activity. FPP028 was shown to possess antipyretic properties in the test of yeast-induced pyrexia. The gastro-erosive activity of phenylbutazone and FPP028 was studied in restraint-stressed rats; in such test the ulcerogenic activity of phenylbutazone appeared to be dose-related; conversely, FPP028 demonstrated a gastro-protective effect since the number of gastric lesions induced either by stress or phenylbutazone treatment was decreased bu FPP028. Our data show that FPP028 is endowed with most of the pharmacological properties of the classic antiinflammatory drugs. Further studies are however needed to more fully elucidate its mechanism of action because our in-vivo data indicate that FPP028 is not an inhibitor of prostaglandin biosynthesis.

Adrenalectomy↗
PubMed1985

Reaction of pig plasma benzylamine oxidase with beta-aminopropionitrile.

Beta-aminopropionitrile (BAPN) is an inhibitor of pig plasma benzylamine oxidase. BAPN is oxidized by benzylamine oxidase. Inhibition develops in a time-dependent fashion upon incubation of BAPN with the enzyme in the absence of substrate. The product of oxidation of BAPN by benzylamine oxidase, cyanacetaldehyde, was identified and prepared by synthesis. It is an irreversible inhibitor of the enzyme.

Aminopropionitrile↗
PubMed1985

Pyridoxamine as inhibitor of the blood plasma benzylamine oxidase and other copper-containing amine oxidases.

Pyridoxamine inhibits rabbit and pig plasma benzylamine oxidase (BAO), the diamine oxidase of pig kidney and the lysyloxidase of pig aorta in-vitro. In-vivo in the rabbit, the inhibitory activity of pyridoxamine on plasma BAO is antagonized by an increase in the level of this enzyme that is dependent on an increase in rate of synthesis, there being no variation in the degradation rate constant.

Animals↗
PubMed1985

Monoamine and diamine oxidative deamination in the longitudinal smooth muscle of guinea pig ileum.

The longitudinal smooth muscle of guinea pig ileum contains three different types of oxidative deaminating enzymes: monoamine oxidase types A and B, diamine oxidase and a soluble clorgyline-deprenyl-resistant benzylamine oxidase. These enzymes have different subcellular locations. The longitudinal smooth muscle of guinea pig ileum oxidatively deaminates beta-phenylethylamine at a much higher rate than benzylamine. beta-Phenylethylamine is a good substrate for monoamine oxidase type B but also for the soluble clorgyline-deprenyl-resistant benzylamine oxidase. On the other hand, benzylamine is oxidised by mitochondrial monoamine oxidase, by the clorgyline-deprenyl-resistant enzyme and by diamine oxidase.

Animals↗
PubMed1983

N-Formylmethionyl-leucyl-phenylalanine: Different releasing effects on human neutrophils and rat mast cells.

N-Formylmethionyl-leucyl-phenylalanine (FMLP) is a synthetic chemotactic peptide which induced beta-glucuronidase and lysozyme release from human neutrophils treated with cytochalasin B. FMLP-releasing effects were rapid and dose dependent. Unlike other secretagogues of neutrophils (e.g., zymosan and immune complexes), FMLP secretory activity was not modulated by acetylcholine, which by itself did not release lysosomal enzymes from human neutrophils. Isolated rat mast cells did not respond to FMLP, which has been demonstrated to release histamine from human neutrophils. Two markers of rat mast cell secretory granules, histamine and beta-glucuronidase, were assayed, but the results were negative for both. In the same experimental conditions, 48/80 released histamine and the enzyme: the ratio of the net percentage release of beta-glucuronidase to the net percentage release of histamine was congruent 0.4.

Acetylcholine↗