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Biomedical subjects

P Roussel

Publications and source records attributed to P Roussel.

At least 145 records · Page 8Linked to original sources
PubMed1983

Contact glass for use with high power lasers--geometrical and optical aspects. Solution for the angle of the anterior chamber.

A new mirror contact glass for irradiation of pathological structures within the angle of the anterior chamber with high power lasers is described. The new contact glass is distinguished by its optimized optical characteristics. Due to its spherical front surface, tipping movements, as necessary in inspection and aiming manoeuvres, have no significant influence on the focus diameter. That the imaging quality is independent of the contact glass manipulations is seen as essential for laser surgical tasks with high power lasers, since changes in the focus diameter critically affect the power density at the focus and thus the intensity of the microsurgical effects. The increased spatial reliability of the laser-induced microexplosion is thought to be a further merit of the new contact glass.

Anterior Chamber↗
PubMed1983

Bonnet monkey cervical mucus glycoproteins. Study of the minor glycoprotein components of periovulatory phase mucus.

Two glycoproteins present in small quantities, in addition to a main glycoprotein, were isolated from the periovulatory phase mucus. The glycoproteins, obtained in minute amounts, showed distinct variations in the relative proportions of sugar residues. The results of analytical as well as chemical studies suggest the existence of two distinct molecular species differing in structure. The main component of the minor glycoproteins, Fraction A, Characterized by Smith degradation and by subsequent methylation and inhibition of hemagglutination, bears similarities to the periovulatory phase main glycoprotein. The other component, Fraction B, characterized by Smith degradation followed by inhibition of hemagglutination, shows structural resemblance to the premenstrual phase glycoprotein.

Amino Acids↗
PubMed1982

Identification of calcium palmitate in gallstones by infra-red spectroscopy.

Crystallographic studies have shown that calcium palmitate was the fourth most frequent crystalline constituent of gallstones, but it has never been detected using an infra-red technique. This report demonstrates that IR spectroscopy represents an accurate and easy method for detection of this compound in gallstones. First, palmitic acid has been unequivocally identified from gallstones after chloroformic extraction in an acidic medium, on the basis of 1H NMR and mass spectra. Secondly, the characteristic bonds of pure calcium palmitate have been well established (2920, 2850, 1575, 1540, 1470, 1430, 1412, 1110, 710 cm-1) enabling the identification of this compound isolated or in association with other components of calculi.

Bilirubin↗
PubMed1982

Primary-structure determination of fourteen neutral oligosaccharides derived from bronchial-mucus glycoproteins of patients suffering from cystic fibrosis, employing 500-MHz 1H-NMR spectroscopy.

The structure of carbohydrate units of bronchial-mucus glycoproteins obtained from cystic fibrosis patients was investigated by 500-MHz 1H-NMR spectroscopy and methylation analysis. To that purpose, the mucin was subjected to alkaline borohydride degradation. Neutral oligosaccharide-alditols, ranging in size from disaccharides to pentasaccharides, were isolated. Eight compounds could be purified to homogeneity; furthermore, three fractions were obtained consisting mainly of two components. For all 14 compounds the primary structure could be elucidated. 500-MHz 1H-NMR spectroscopy was found to be effective in detecting heterogeneity and to be invaluable for the determination of structures in mixtures of oligosaccharide-alditols. The structures can be divided into two groups depending on the core disaccharide. One group contains Gal(beta 1 leads to 3)GalNAc-ol as common structural element, the other GlcNAc(beta 1 leads to 3)GalNAc-ol. Both disaccharides were identified as such; the other compounds can be conceived as extensions thereof. The most complex representatives of the two groups are: (formula; see text) The italicized structural elements, comprising the SSEA-1 determinant and the type-1 blood-group-H determinant, are novel sequences in oligosaccharide chains of mucin-type glycoproteins.

Chemical Phenomena↗
PubMed1982

Use of lectins for detection of glycoconjugates in the glandular cells of the human bronchial mucosa.

Paraffin-embedded human bronchial biopsies, obtained in macroscopically healthy areas, were examined using nine peroxidase-bound lectins. These were either isolated or purified by affinity column chromatography (Ulex europeus, Triticum vulgare, Glycine max, and Arachis hypogatea lectins) or commercial preparations (Lotus tetragonolobus, Canavalia ensiformis, Helix pomatia, Phaseolus vulgaris, and Lens culinaris lectins) and conjugated to peroxidase (except for concanavalin A). These labeled lectins were used as specific molecular probes to localize differences in carbohydrate-containing components present in the different types of glandular cells of human bronchial mucosa. The choice of fixative was crucial and tests used for this study have shown that Carnoy's solution seems to be the most appropriate solution to preserve mucous glycoproteins in situ. Comparison of the affinity of several lectins for human bronchial glycoproteins and for bronchial mucosa demonstrates the predominance of serum-type glycoproteins in serous cells of the submucosal glands and mucin-type glycoproteins in mucous cells of the submucosal glands and in goblet cells of the bronchial epithelium. Furthermore the data obtained with some lectins, such as Helix pomatia agglutinin, suggest that there are some differences in the mucins synthesized by goblet cells and by mucous cells.

Bronchi↗
PubMed1981

Comparative action of reducing agents on fibrillar human bronchial mucus under dissociating and non-dissociating conditions.

Gel=like or fibrillar human bronchial mucus was reduced with mercaptoethanol under dissociating and non-dissociating conditions. Bronchial mucus was solubilized in both conditions; but reduction in phosphate buffer induced more extensive depolymerization of mucus glycoproteins than obtained under reduction in guanidine. Moreover, mucins prepared by reduction in non-dissociating conditions contained less amino acid and more carbohydrate. These data strongly suggest that reduction under non-dissociating conditions does not act only on disulfide bridges but also induces the activation of a mucolytic enzymatic system. They also would explain some of the discrepancies observed in the molecular weight determination and chemical composition of human bronchial mucus glycoproteins purified after reduction of gel-like mucus under different conditions.

Bronchi↗
PubMed1981

[Effect of trypsin on the cell surface : influence on the lysosomal exocytosis of alveolar macrophages of the guinea pig].

Secretion of the main lysosomal hydrolase, N-acetyl-beta-D-glucosaminidase of Guinea Pig alveolar macrophages was studied in vitro; without stimulus of phagocytosis or pinocytosis, glycosidase secretion was increased by trypsin. Enzymatic activity secreted under trypsinisation was heterogeneous as compared to the enzymatic activity secreted by control cells: under incubation with Concanavalin A (Con A), glycosidase activity secreted by trypsinised cells decreased by 30%, whereas Concanavalin A did not alter enzymatic activity secreted by control cells.

Acetylglucosaminidase↗
PubMed1981

Clinical studies on the efficiency of high power laser radiation upon some structures of the anterior segment of the eye. First experiences of the treatment of some pathological conditions of the anterior segment of the human eye by means of a Q-switched laser system.

A series of pathological conditions such as pupillary block glaucoma, angle block glaucoma, acoria, pupillary membranes and goniosynechias of various origins have been treated successfully by means of pulses emitted from a Nd:YAG Q-switched laser above optical breakdown threshold. Since linear absorption is not required, non-pigmented or entirely transparent structures are easily dissected by this method. We have also opened the supraciliary and suprachoroidal space in a series of cases of wide angle glaucomas. In all cases however, the clefts closed by secondary wound reactions. This method may be applied to extracapsular cataract surgery for opening the anterior capsule before lens extraction and to the hydrophthalmic eye.

Cataract Extraction↗
PubMed1980

Oligosaccharides of human bronchial glycoproteins. Neutral di- and trisaccharides isolated from a patient suffering from chronic bronchitis.

Human bronchial glycoproteins from a patient suffering from chronic bronchitis were subjected to alkaline borohydride degradation and a heterogeneous mixture of reduced oligosaccharides and glycopeptides was obtained. The shortest neutral oligosaccharides were subsequently fractionated by DAX4 anion exchange chromatography into 12 fractions. Five major oligosaccharides were purified by preparative paper chromatography. Their structures were determined by using periodic oxidation, methylation analysis, gas liquid chromatography-mass spectrometry, and enzymatic degradation. Two oligosaccharides and three trisaccharides were characterized as galactose (Gal) beta 1 leads to 3 N-acetylgalactosaminitol (GalNActitol), N-acetylglucosamine (GlcNAc) beta 1 leads to 3 GalNActitol, Gal 1 leads to 4 GlcNAc 1 leads to 3 GalNActitol, GlcNAc 1 leads to 3 Gal 1 leads to 3 GalNActitol and fucose alpha 1 leads to 2 Gal beta 1 leads to 3 GalNActitol.

Bronchi↗
PubMed1980

[Bronchial secretions: biochemical study. Physiopathological aspects].

Among the chief constituents of bronchial secretions, serum or mucus proteins and mucins are the parameters enabling definition of the functional state of the tracheo-bronchial mucosa. The use of bronchial detergents in normal subjects or subjects with moderate secretions leads to the study of physiological sputum or to definition of the evolution of chronic bronchitis. Results of immunoglobulins G and A dosages, values of IgA 7S/IgA 11S and of IgA/serum albumin ratio are reported. In the same way, the equilibrium of secretion of mucins estimated by the percentage of the different classes of mucins separated according to their acidity degree is an evaluation element of the evolution degree of chronic bronchitis. The studies of correlation between rheological properties and chemical structure of bronchial secretions are reported. They postulate an original concept on the use of mucolytics.

Bronchi↗