Marie-Claude Bomsel-Demontoy

Publications of Marie-Claude Bomsel-Demontoy

• Influence of molt on plasma protein electrophoretic patterns in bar-headed geese (anser indicus).

  Authors: Yannick Roman, Marie-Claude Bomsel-Demontoy, Julie Levrier, Dorothée Ordonneau, Daniel Chaste-Duvernoy, Michel Saint Jalme

  Journal of wildlife diseases. 08/2009; 45(3):661-71.

  Plasma protein electrophoresis is recognized as a reliable diagnostic tool in avian medicine; however, the influence of circannual phenomena such as molt on protein electrophoregrams is poorlyPlasma protein electrophoresis is recognized as a reliable diagnostic tool in avian medicine; however, the influence of circannual phenomena such as molt on protein electrophoregrams is poorly documented. The molt is a period of heavy hormonal and metabolic change in birds. The purpose of this study was to investigate the effects of molt on total protein concentration and electrophoresis patterns in birds. Blood samples were taken from 19 Bar-headed Geese (Anser indicus) from mid-May to mid-August, at 15-day intervals. At the same time, molting stage of each bird was recorded. Total protein concentrations were measured and plasma agarose gel electrophoresis was performed on these samples. The Bar-headed Goose was chosen as a model, because they molt over a very short period. The total protein concentration and albumin, alpha-2, beta, and gamma fractions were at their minimum values during molt, whereas the prealbumin and alpha-1 fractions rose to their maximum levels. This study provides baseline information relevant to changes occurring in avian proteinograms throughout the molt. The increase in prealbumin and alpha-1 fractions may be related to an increase in plasma thyroid hormones during molt. The decrease observed in albumin, alpha-2, beta, and gamma fractions may be related to protein and energy shifts toward feather growth, as well as to an expansion of the circulatory system located around the feather follicles with secondary dilutional effects on protein fractions. From a clinical point of view, the observed changes associated with molting were less significant than initially expected, and would not likely results in incorrect diagnoses based on interpretation of the protein electrophoretic patterns.

• Identification of apolipoprotein A-I in the alpha-globulin fraction of avian plasma.

  Authors: Yannick Roman, Bertrand Bed'hom, Alain Guillot, Julie Levrier, Daniel Chaste-Duvernoy, Marie-Claude Bomsel-Demontoy, Michel Saint Jalme

  Veterinary clinical pathology / American Society for Veterinary Clinical Pathology. 04/2009;

  Background: Plasma protein electrophoresis is frequently used in birds as a tool for the diagnosis and monitoring of disease. Identification of proteins in individual peaks can help improve ourBackground: Plasma protein electrophoresis is frequently used in birds as a tool for the diagnosis and monitoring of disease. Identification of proteins in individual peaks can help improve our understanding of changes in protein concentration in physiologic and pathologic conditions. Objective: The aim of this study was to verify the presence and identity the protein(s) in the prominent alpha-globulin peak of orange-winged parrots (Amazona amazonica), black kites (Milvus migrans), and rock pigeons (Columba livia). Methods: Heparinized plasma samples were obtained from 12 birds of each species. Agarose gel electrophoresis and total protein concentration were determined using standard techniques. One plasma sample from each species was then electrophoresed using high-resolution agarose gels to isolate the alpha-globulin band. Gel strips were digested in trypsin and peptides were extracted and analyzed using liquid chromatography with tandem mass spectrometry. De novo sequencing was used to identify the protein based on homology scoring against a protein database. Results: Electrophoresis verified the presence of a single prominent alpha-globulin peak, usually in the alpha(1)-region, that had a median concentration of 9.4 g/L (range, 2.1-11.7 g/L, 21.6% of total protein) in parrots, 12.2 g/L (10.4-13.2 g/L, 35.9%) in kites, and 10.7 g/L (9.0-11.5 g/L, 40.0%) in pigeons. Mass spectrometry and sequencing analysis unequivocally identified the protein as a mature circulating form of apolipoprotein A-I (apo A-I) in all 3 species. Conclusions: Apo A-I accounts for the prominent alpha-globulin peak and comprises a major proportion of total protein concentration in diverse avian species. As a high-density lipoprotein and negative acute phase protein with a pivotal role in cholesterol homeostasis, further study is warranted to determine the significance of changes in apo A-I concentration in avian electrophoretograms.

• EFFECT OF HEMOLYSIS ON PLASMA PROTEIN LEVELS AND PLASMA ELECTROPHORESIS IN BIRDS.

  Authors: Yannick Roman, Marie-Claude Bomsel-Demontoy, Julie Levrier, Daniel Chaste-Duvernoy, Michel Saint Jalme

  Journal of wildlife diseases. 02/2009; 45(1):73-80.

  Protein electrophoresis is recognized as a reliable diagnostic tool for birds even though results are seldom pathognomonic. Unfortunately, this technique is underused in avian medicine because manyProtein electrophoresis is recognized as a reliable diagnostic tool for birds even though results are seldom pathognomonic. Unfortunately, this technique is underused in avian medicine because many factors interfere with electrophoresis patterns; hemolysis is one of these factors and is often associated with improper specimen handling. In human laboratory medicine, hemolysis is a known interference factor that can lead to erroneous results. Published data on the influence of hemolysis on protein electrophoresis in birds is currently restricted to a single study in Psittacidae. The aim of this study was to further investigate this effect and to analyze potential interspecific differences. Blood samples were drawn from 28 Black Kites (Milvus migrans) and 19 Bar-headed Geese (Anser indicus) and separated into two aliquots. One aliquot was dipped into liquid nitrogen for 5 sec in order to cause freeze-thawing hemolysis before centrifugation. Total plasma protein concentration, plasma hemoglobin concentration, and plasma protein electrophoresis patterns were determined for both hemolyzed and nonhemolyzed samples. In both species, hemolysis resulted in falsely elevated total plasma protein concentration. In Bar-headed Geese, hemolysis caused a rise in the gamma fraction. In Black Kites, this rise involved not only the gamma fraction but also the beta fraction, stressing the potential for species-related differences. In both species, the effects of hemolysis mimicked a chronic inflammatory condition with resulting antigenic stimulation.