[Beta-D-mannosidase].

Among the lysosomal hydrolytic enzymes, and especially the exoglycosidases which carry out the degradation of the glycan moieties of glycoconjugates, the beta-D-mannosidase (beta-MAN) was the least investigated, up to the discovery of the inherited deficiency, in 1979-1980 for the caprine disease, and in 1986 for the human one. The beta-mannosidosis is characterized by mental retardation in children and by severe osteoarticular damage in kids. In both cases occurs the storage of oligosaccharides which are later excreted in urine: beta-mannosyl (1-4)-N-acetyl-beta-glucosaminyl (1-4)-N-acetylglucosamine, and beta-mannosyl (1-4)-N-acetylglucosamine in caprine disease, but only the last disaccharide in human patients.

Patterns of alpha-L-fucosidase in acute myeloid leukemia cells. Comparison with promyelocytic HL-60 cell line.

Changes were observed in alpha-L-fucosidase forms in cells from acute myelocytic leukemias (AML). Total alpha-L-fucosidase activity was not significantly different for normal granulocytes and leukemic cells, but enzymic profiles obtained by chromatofocusing are quite different. In granulocyte profile, two main peaks are present (B and more acidic A) which were eluted at pH 5.

Relationship between smoking status and serum lipids in a hyperlipidemic population and analysis of possible confounding factors.

The aim of our study was to estimate the potential relationship between smoking behavior and other coronary heart disease risk factors in 250 hyperlipidemic patients. We present data obtained through self-reporting of the number of cigarettes smoked per day, measurements of three tobacco markers, and data on dietary habits and lipid variables. We measured cotinine (by HPLC) and thiocyanate and used a recent colorimetric assay for the indirect evaluation of the nicotine metabolites in a single urine specimen.

Mammalian beta-D-mannosidase and beta-mannosidosis.

Lysosomal beta-D-mannosidase is the last exoglycosidase involved in the sequential degradation of the N-glycosylproteins glycans. Research on this enzyme was restricted before the discovery of its hereditary deficiency, first in goat (1981) and later in man (1986). We describe the biochemical aspects of these beta-mannosidosis and the properties of the beta-mannosidases of mammalian origin.

[Alpha-L-fucosidase of normal and pathological blood cells].

The glycosidases, enzymes which participate in the degradation of glycoproteins and glycolipids inside the lysosomes are themselves glycoproteins and, for one enzyme, several forms may be isolated in tissues and in biological fluids, corresponding to variations in the composition or the structure of their glycanic moiety. We have previously studied the different forms of alpha-L-fucosidase in human serum, kidney and urine. Some modifications of the glycanic fraction of glycoproteins have been described in various forms of tumoral cells; therefore, we have attempted to verify if the alpha-L-fucosidase of blood cells might be a useful marker in the diagnosis of leukemias, using the enzymic pattern obtained by chromatographic or electrofocusing methods.

Microheterogeneity of alpha 1-acid glycoprotein: variation during the menstrual cycle in healthy women, and profile in women receiving estrogen-progestogen treatment.

The concentration of alpha 1-acid glycoprotein (AGP) was measured in sera from 23 women, 14 pregnant women, 10 women receiving estrogen-progestogen treatment and 12 men. All sera were further subjected to crossed affino-immunoelectrophoresis with addition of conA in the first dimension and alpha-methylglucopyranoside in the second dimension. The distribution of AGP into three microheterogeneity forms, which were the result of this analysis, was estimated by measuring the area under the precipitation curve.

Alpha-L-fucosidase isoenzyme pattern in hairy cell leukaemia.

alpha-L-Fucosidase isoenzymes pattern in hairy cell leukaemia (HCL) is characterized by the disappearance of the more acidic form when compared to normal lymphocytes. Our data seem to indicate that this profile could not be related to the T or B phenotype because in normal lymphocytes (mainly T), MO cells possessing T markers, as well as lymphocytes from chronic lymphoid leukaemia (CLL) known to exhibit normal-like B phenotypes two alpha-L-fucosidase forms are identified and especially the more acidic one.

Human urinary and renal alpha-L-fucosidases. A comparative study.

1. Enzymatic forms of alpha-L-fucosidase from human renal tissue and urine were investigated. 2.

On some glycosidases (beta-D-mannosidase, alpha-L-fucosidase, N-acetyl-beta-D-glucosaminidase) of human seminal plasma.

The glycosidase activities (beta-D-mannosidase, alpha-L-fucosidase and N-acetyl-beta-D-glucosaminidase) have been compared in whole and split ejaculate samples from men whose couple suffers from infertility. The site of secretion of enzymatic activities is either prostatic or epididymal. The three enzymatic activities have possibly different origin and should constitute new biochemical markers of male genital tract.

Alpha-L-fucosidase activity in normal human lymphocytes.

After DEAE-Trisacryl chromatography two forms of alpha-L-fucosidase have been characterized in normal human lymphocytes. These enzymatic forms were different with respect to their optimum pH, kinetic properties and isoelectric behaviour. After neuraminidase treatment two forms are still observed with a neutral shift in pI values.

Sodium butyrate-induced structural and functional modifications in proteins of cultured rabbit articular chondrocytes.

The effects of sodium butyrate (NaB), a potent growth inhibitory agent, on actin distribution, alkaline phosphatase (AP) activity and protein content were studied in rabbit articular chondrocytes in monolayer culture. When growth of randomly proliferating cells was arrested with NaB, actin stress fibers appeared; at the same time, vimentin-containing intermediate filaments and tubulin-containing microtubules were dispersed. Concomitantly, membrane AP activity and protein content were increased.

[Urinary excretion of N-acetyl-beta-D-glucosaminidase (NAG) and its isoenzyme B as a marker of the nephrotoxicity of gentamicin: re-test from an animal model].

A high level of NAG urinary excretion with marked isoenzyme B excretion are commonly considered as an indicator of aminoglycoside nephrotoxicity. The urinary excretion of NAG following gentamicin treatment was studied in rabbit. The rabbits received gentamicin at equivalent therapeutic (5 and 20 mg/kg/j) or toxic (50 mg/kg/j) doses during four days.

Partial characterization of intracellular and secreted glycosidases from rabbit articular chondrocytes in culture.

N-Acetyl-beta-hexosaminidase, beta-galactosidase and beta-glucuronidase activities were shown to be present in cultured rabbit articular chondrocytes. Secretion of enzyme activity seems to preferentially result in the accumulation of N-acetyl-beta-hexosaminidase. Three days after seeding, the amount of N-acetyl-beta-hexosaminidase activity found in the medium accounts for about 140% of the total N-acetyl-beta-hexosaminidase activity after complete disruption of the cell pellet.

[Quantification of proteinuria by measurement of the protein/creatinine ratio].

Accurate quantification of urinary protein excretion is difficult due to problems in 24-hour urine collection. We have evaluated the value of the protein/creatinine ratio in one single urine sample. There was an excellent correlation between this ratio and the protein content of a 24-hour urine collection [Pu (g/24 h) = 11.

beta-D-mannosidase in human polymorphonuclear leukocytes and lymphocytes: a comparative study.

All lymphocytes and polymorphonuclear leukocytes (PMNL) beta-D-mannosidase activities are adsorbed on DEAE-Trisacryl column at pH 7.0. Only one form is eluted with a 0.

beta-Mannosidase in human serum and urine. A comparative study.

All serum and urine beta-mannosidase activities are adsorbed on a DEAE-Trisacryl column at pH 6. Only one form is eluted with a NaCl linear gradient. The two enzymes, isolated from either serum or urine exhibit similar properties.

Decreased serum beta-D-mannosidase activity in diabetic patients, in comparison with other glycosidases.

A study of four lysosomal glycosidases' activities was carried out on sera from 64 diabetic patients, which revealed important variations in comparison with the activities observed in sera of control subjects. Depending on the type of diabetes mellitus (I, insulin-dependent, or II, non-insulin-dependent), three activities were more or less increased: alpha-L-fucosidase, alpha-D-mannosidase, and N-acetyl-beta-D-glucosaminidase, in agreement with previously published results. Against that, the beta-D-mannosidase activity shows a highly significant decrease in sera from either diabetic type.

Early monitoring of human renal transplantations by N-acetyl-beta-D-glucosaminidase isoenzyme activities in urines.

Monitoring of variations in N-acetyl-beta-D-glucosaminidase (NAG) urinary activity, following renal transplantation, has been proposed for the early diagnosis of rejection episodes. In this study, the measurement of urinary NAG-B activity was conducted as a complement to total NAG (A + B) measurement, which is normally used alone. Selective measurement of NAG-B activity is carried out after fixation of NAG-A on ion exchanger in test tubes.

Inhibition of A and B N-acetyl-beta-D-glucosaminidase urinary isoenzymes by urea.

A urinary fraction which inhibits the activity of N-acetyl-beta-D-glucosaminidase (NAG) has been isolated and identified as being urea. Usually present in high concentration, urea appears to be the only urinary component responsible for the frequently observed urinary NAG inhibition. The inhibition of the two urinary NAG isoenzymes A and B is competitive with respective Ki values of about 70 mmol/l and 60 mmol/l.