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M Lemonnier

Publications and source records attributed to M Lemonnier.

At least 37 records · Page 2Linked to original sources
PubMed1985

Use of chemical ionization in gas chromatographic/mass spectrometric screening of human urine for disaccharides containing inositol.

Gas chromatography/mass spectrometry (GC/MS) in the positive chemical ionization (CI) mode was used to screen normal urine for inositol-containing disaccharides in the form of permethylated derivatives, after borodeuteride reduction of the reducing saccharides. Ammonia was the reactant gas. The results revealed the existence of deoxyhexosyl-inositol and hexosyl-inositol disaccharides, and of a new compound, N-acetylhexosaminyl-inositol disaccharide. Up to four isomers of deoxyhexosyl-inositol could be present in the same sample even though only one of them has so far been fully characterized in man. As regards the hexosyl-inositols, one to three isomers were present in the same sample and probably corresponded to the three isomers of galactosyl-inositol recently described in man. N-Acetylhexosaminyl-inositol (identified elsewhere by us as N-acetylgalactosaminyl-alpha (1-1)-myo-inositol) was seen in only a few samples. No relationship can be found between the excretion of all these inositol-containing disaccharides on the one hand, ABO(H) blood group and 'Secretor' status (Se or sese) of the donors on the other. The gas chromatographic CI mass spectrometric technique used here with various ammonia pressures can be applied to the screening of other biological fluids or tissues for inositol glycosides.

Disaccharides↗
PubMed1984

Isolation and characterization of 1-O-alpha-2-acetamido-2-deoxy-D-galactopyranosyl-myo-inositol from pregnancy urine.

A new neutral glycoside of myo-inositol was isolated from the pregnancy urine of a single donor. Its structure was investigated by 1H-NMR spectroscopy and mass spectroscopy. It was identified as 1-O-alpha-2-acetamido-2-deoxy-D-galactopyranosyl-myo-inositol. No such structure or sequence has previously been reported in either myo-inositol or glucose glycosides.

Disaccharides↗
PubMed1984

The structure of sialyl-glycopeptides of the O-glycosidic type, isolated from sialidosis (mucolipidosis I) urine.

Sialyl-glycopeptides containing an O-glycosidically linked tetrasaccharide chain were obtained from the urine of a patient suffering from mucolipidosis I. Isolation of these compounds was achieved by gel filtration, ion-exchange chromatography and preparative paper chromatography. Their structures were determined by a combination of carbohydrate and amino acid analysis, dansylation, periodate oxidation, methylation studies, enzymatic hydrolysis and 1H-NMR spectroscopy, to be as follows: (formula; see text) wherein R = peptide linked through -Thr-, -Ser-Thr- or -Thr-Ser-. The finding of these glycopeptides in urine shows that mucolipidosis I is characterized by a general "glycoprotein-specific" sialidase deficiency. The possibility of the existence of a human endo-alpha-N-acetylgalactosaminidase is discussed.

Amino Acids↗
PubMed1979

[Fucosidosis and blood group substances in the urine].

Glycopeptide and oligosaccharide fractions obtained from fucosidosis urine contains more Lea activity (4-8 fold) than control urine. Both fucosidosis fractions also contained Leb and H activities, no A activity in contrast to the salivary and erythrocyte phenotypes (A, Le a+ b-). The amount of Leb activity is lower in both fractions (1) and (2) than that of Leb control children (4-16 fold decrease). Blood group A activity was not detected at any concentration used (less than or equal to 50 fold-concentrated urine) whereas A activity was found in (A, Le a- b+) control urine. On the contrary, both fucosidosis fractions contained H activity, whereas A (Le a- b+) control children fractions had none (less than or equal to 50-fold concentrated urine). H and Leb activity might originate from Lea precursor apart from the "non-secretory" type of the patient.

Blood Group Antigens↗
PubMed1978

[Excretion of sialoglycopeptides in mucolipidosis I].

Mucolipidosis I involves a tremendous increase of the urinary excretion of sialoglycopeptides and sialyloligosaccharides. This enhancement is due to the excretion of O- and N-glycosidic peptides and oligosaccharides, which normal urine is devoid of as shown by the chemical composition and electrophoresis or thin-layer analysis. This finding is in agreement with the recent finding of an alpha-neuraminidase deficiency for this disease.

Child↗
PubMed1978

[Structural characteristics of the blood group N determinant, tested with anti-N lectin from Vicia graminea].

Crude extracts of Vicia graminea seeds agglutinate human N erythrocytes as anti-N immunsera. The anti-N lectin is purified after precipitations with ammonium sulphate of crude extracts, DE52 Whatman chromatography and sephadex G150 gel filtration. Its homogeneity is demonstrated by physical and immunological methods. The structure determinant for the Vicia graminea anti-N activity was investigated: --with the major glycoprotein of N erythrocytes. --with glycoconjugates isolated from urine of normal human N-blood group as urinary glycoconjugates are probably related to the membrane glycoprotein catabolism. Purification and characterization of glycoconjugates are undertaken by gel filtration and non-exchange chromatography. This purification is checked by hemagglutination-inhibition test with V. graminea lectin. Biochemical characterization of active glycoconjugates gives way to the carbohydrate determinant recognized by anti-N antisera and Vicia graminea lectin.

Blood Group Antigens↗
PubMed1978

[Mucolipidosis type I. Sialidosis due to alpha-2-6-neuraminidase deficiency with neurological symptoms].

A case close to mucolipidosis I was observed and the description of this mucolipidosis has to be revised since there were initially some confusions with mannosidosis. Three types of abnormalities appear to be important in its distinction from the other types of oligosaccharidoses: presence on the fundus of a cherry-red spot; in the bone marrow, reticulo-histiocytic cells, whose central nucleus is surrounded by multiple optically empty droplets; very elective overload of the Kupffer cells. 3a neurological syndrome with cerebellar ataxia appears in the evolution. However, it is not present in our patient nor the electroencephalogram changes. This latter point does not authorize the definite identification of our case with Spranger and Wiedemann description of mucolipidosis I especially as the neuraminidase deficiencies are certainly heterogenous.

Child, Preschool↗
PubMed1978

Sialic acid-containing glycoconjugates in human lactation urine.

The excretion rate of neutral hexoses, fucose and sialic acid of oligosaccharide and glycopeptide fraction has been determined in lactation urine. Thin layer chromatography has been used to investigate the excretion pattern of oligosaccharides, specially sialyl-oligosaccharides, during the course of lactation and after weaning. Lactation urine contains sialyloligosaccharides which are not present in normal urine and their presence has been studied up to the 3rd week after weaning. These results indicate a mammary origin for most of these compounds and confirm the hypothesis of previous research.

Female↗
PubMed1976

Molecular forms of Electrophorus acetylcholinesterase. Molecular weight and composition.

Molecular weights for the series of six Electrophorus acetylcholinesterase forms have been determined either by the sedimentation-diffusion equilibrium method or, particularly in the case of the very scarce G' and G inches forms, from their Stokes radius and sedimentation coefficient values. Both methods are in excellent agreement. The results provide good evidence for the model previously proposed, G inches, G' and G containing one, two and four subunits, whereas A, C and D possess, in addition to respectively one, two and three tetrameric sets of such subunits, a structural element, the tail. Although the amino acid composition of 'tailed' and globular forms did not reveal any significant feature of this element, its mass, about 100 000 daltons, could be deduced from a comparison of molecular weights for the two classes of acetylcholinesterase forms. This value is in close agreement with electron microscopic data. The tail is thought to consist of three 30 000-dalton strands.

Acetylcholinesterase↗