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Registros recuperados: 27 | |
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Robledo, Jaf; Boulo, Viviane; Mialhe, Eric; Despres, Béatrice; Figueras, Antonio. |
Digestive glands of mussels Mytilus edulis from Brittany, France, infected with Marteilia sp. (Ascetospora) were used to purify the parasite. A modification of a previously used purification protocol increased purification efficiency, permitting sporangial primordia and sporangia of Marteilia sp. to be obtained. Mouse (Balb/c) monoclonal antibodies were generated against this parasite. From the fusion, 26 monoclonal antibodies against Marteilia sp. were obtained. Antibodies from 6 clones reacted only with Marteilia sp. cells and not with normal host tissues. Four of these antibodies (1/1-3, 3/1-1, 4/1-1 and 6/2-3) reacted with the sporangia wall and two with the spore cytoplasm (9/1-1 and 12/5-1). Antibodies cross-reacted with Marteilia refringens from... |
Tipo: Text |
Palavras-chave: Marteilia sp.; Mytilus edulis; Monoclonal antibodies. |
Ano: 1994 |
URL: http://archimer.ifremer.fr/doc/00196/30730/29404.pdf |
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Le Gall, G; Bachere, Evelyne; Mialhe, Eric. |
During a study of Rickettsiales-like organisms (RLO) in Pecten maximus gill, histological observation of free RLO in hemoclymph led us to consider interactions between the pathogen and the hemocytes. Firstly, the production of oxygen radicals by hemocytes was established using a luminol-enhanced chemiluminescence method with zymosan axs stimulant. The effects of serveral inhibitors of oxidative metabolism were investigated. The internalization of RLO into hemocytes was demonstrated by electron microscopy but was not related to chemiluminescent activity. The possible involvement of RLO acid phosphatase as the inhibitor of respiratory burst was assessed. |
Tipo: Text |
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Ano: 1991 |
URL: http://archimer.ifremer.fr/doc/1991/publication-2759.pdf |
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Boulo, Viviane; Hervio, Dominique; Morvan, Annie; Bachere, Evelyne; Mialhe, Eric. |
The chief importance of hemocytes as immune effectors in molluscs has led to develop researches for in vitro culture. The chemiluminescence technique has been used to estimate the phagocytosis capacity of Crassostrea gigas hemocytes according to different culture media and times. Sea water was used as a basic medium. Additives, such as antibiotics or glucose and buffers, such as Tris or Hepes, were tested as weIl as artificial sea water. Hemocyte chemiluminescence activities were recorded at t=o in relation to the medium composition. The highest values were observed when hemocytes were kept in sea water without any modification. Whichever medium, chemiluminescence activity was substantially decreased when hemocytes were previously kept in vitro for a few... |
Tipo: Text |
Palavras-chave: Crassotrea gigas; Oyster; Bonamia ostreae; Pathogens; Molluscs; Hemocytes. |
Ano: 1991 |
URL: http://archimer.ifremer.fr/doc/1991/acte-4115.PDF |
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Le Gall, G; Mialhe, Eric. |
Significant mortalities have been observed in populations of Saint-Jacques scallops Pecten maximus, in association with numerous intrace1lular colonies of Rickettsiales-like organisms (RLO) in the gi1ls. Isolation of the procaryotes from infected tissues and their subsequent purification were achieved by a specific protocol based on differential and isopycnic centrifugations on sucrose and renografin density gradients. The purity and integrity of purified procaryotes were verified by electron microscopy. Specific polyclonal antibodies were prepared for serological characterization. Fifteen major constituent proteins were electrophoretically identified, their molecular weights ranging between 148 and 16 kD. Ten enzyme activities were biochemica1ly... |
Tipo: Text |
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Ano: 1992 |
URL: http://archimer.ifremer.fr/doc/1992/publication-2769.pdf |
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Mialhe, Eric; Boulo, Viviane; Elston, Ralph; Hill, Barry; Hine, Michel; Montes, Jaime; Mont, Jaime; Banning, Paul Van; Grizel, Henri. |
Murine moncolonal and polyclonal antibodies to antigesn of Bonamia ostreae were assessed for serological comparaison of parasites associated with different geographical originns of flat oyster, Ostrea edulis, and with Tiostrea lutaria. All Bonamia isolates from O. edulis reacted similary with polyclonal and monoclonal antibodies. The parasite associed with Tiostrea lutaria which lacks reactivity with 20 B 2 MAB must be considered as a serologically distinct from of B. ostreae |
Tipo: Text |
Palavras-chave: Serological comparison; Polyclonal and monoclonal antibodies; Tiostrea lutaria; Ostrea edulis; Bonamia; Comparaison sérologique; Anticorps polyclonaux et monoclonaux; Tiostrea lutaria; Ostrea edulis; Bonamia. |
Ano: 1988 |
URL: http://archimer.ifremer.fr/doc/1988/publication-3101.pdf |
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Grizel, Henri; Mialhe, Eric; Chagot, Dominique; Boulo, Viviane; Bachere, Evelyne. |
Research on bonamiasis, an epizootic disease of the edible oyster Ostrea edu/is caused by the protozoan Bonamia ostreae, is discussed in relation to oyster fanning, research technology, epizootiology, and management. Morphological and infectious characteristics of the parasite are described. Recent progress in isolation and purification of the parasite have permitted investigations into host defense mechanisms, parasite infectivity, and the development of a mol1usc-pathogen mode!. |
Tipo: Text |
Palavras-chave: Epizootic disease; Pathology; Protozoan; Bonamia ostreae; Oysters. |
Ano: 1988 |
URL: http://archimer.ifremer.fr/doc/1988/publication-3120.pdf |
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Bachere, Evelyne; Hervio, Dominique; Mialhe, Eric. |
Microbicidal phagocytic function and oxidative metabolism of the hemocytes of 2 oyster species, Ostrea edulis and Crassostrea gigas, were investigated using a luminol-enhanced chemiluminescence (technique. First, experimental parameters adapted to marine bivalve hemocytes were established on hemolymph pools of C. gigas in order to obtain qualitatively and quantitatively homogeneous samples and so to perform statistically comparable assays. The use of Modified Alsever Solution (allowed hemocytes to be kept non-aggregated and in a non-stimulated state until starting the assays. A number of aliquots of 2 X 10(5) hemocytes with an MAS final concentration of 3.5 % showed high chemiluminescent response after stimulation by zymosan particles A particle:hemocyte... |
Tipo: Text |
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Ano: 1991 |
URL: http://archimer.ifremer.fr/doc/1991/publication-2761.pdf |
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Mortensen, Stein Hàkon; Bachere, Evelyne; Le Gall, Ghislaine; Mialhe, Eric. |
Infectious pancreatic necrosis virus (IPNV), serotype N1 isolated from scallops Pecten maxjmus in Norway, was propagated and used in both inoculation and bath challenge experiments with scallops in vivo. Although virus titers measured in scallop tissues decreased, depuration of virus was not complete during the experimental periods. TPNV was still detectable 11 mo after injection. The highest virus titer was found in the hepatopancreas, but virus was also detectable in other tissues, as well as in the hemolymph. After a bath challenge, uptake of IPNV was shown. Virus was present in hepatopancreas, gonad, kidney, mantle, gill, rectum and in the hemolymph 1 d after the uptake. The titer was highest in the hepatopancreas where virus was detectable at the end... |
Tipo: Text |
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Ano: 1992 |
URL: http://archimer.ifremer.fr/doc/1992/publication-2767.pdf |
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Cochennec, Nathalie; Hervio, Dominique; Panatier, B; Boulo, Viviane; Mialhe, Eric; Rogier, H; Grizel, Henri; Paolucci, F. |
Currently recognition of molluscan diseases relies heavily upon light microscopic examination of stained histological sections of molluscan tissues Such histopathological methods are time consuming and relatively inefficient In the study of ongoing epizootics Alternatively, more effluent investigative tools are needed to accelerate disease recognition and quantification Such methods are needed to prevent control and eradicate molluscan diseases This paper reports the development of a direct sandwich enzyme-lmmunosorbent assay (ELISA) for the ascetosporan intrahemocytic parasite Bonamiao ostreae of the flat oyster Ostrea edulis. Bonamiasis is a commercially important epizootic disease of oysters A Bonamia-specific monoclonal antibody is employed in the... |
Tipo: Text |
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Ano: 1992 |
URL: http://archimer.ifremer.fr/doc/1992/publication-2765.pdf |
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Kellner-cousin, Kristell; Le Gall, G; Despres, Béatrice; Kaghad, M; Legoux, P; Shire, D; Mialhe, Eric. |
Genomic DNA fragments of a rickettsia-like organism (RLO) of Saint-Jacques scallop, Pecten maximus, were extracted from purified RLO and cloned. A DNA sequence of 1500 bp taken from one of the sequenced clones was coupled to horseradish peroxidase and the resulting probe was assayed for the diagnosis of RLO by nucleic acid hybridization. The specificity of the probe for RLO DNA was established from its lack of hybridization with scallop DNA. The sensitivity limit of the probe detected by enhanced chemiluminescence was determined to be around 500 ng of total RLO nucleic acids, equivalent to about 2.5 X 106 copies of RLO DNA. A pair of polymerase chain reaction (PCR) primers were synthesized that amplified a 1300 bp segment of the 1500 bp RLO fragment. After... |
Tipo: Text |
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Ano: 1993 |
URL: http://archimer.ifremer.fr/doc/1993/publication-2771.pdf |
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Le Gall, G; Mialhe, Eric; Chagot, D; Grizel, Henri. |
Rickettsia-like microorganisms were described in gill endothelial cells during mass mortalities of Saint-Jacques scallops Pecten maximus in Saint-Brieuc Bay (North Brittany, France) during winter 1985-86. In order to evaluate the epizootiological significance of rickettsiosis of scallops, an analytical and descriptive epizootiological study was undertaken. The study included the geographic distribution, incidence and severity of the disease for several northern European and French scallop populations. Since the center of French scallop production is in Saint-Brieuc Bay, epizootiological investigations were concentrated in this area. Dissemination appeared to be by horizontal transmission. The pathogenic significance of the rickettsia-like organism in... |
Tipo: Text |
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Ano: 1991 |
URL: http://archimer.ifremer.fr/doc/1991/publication-2758.pdf |
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Hervio, Dominique; Chagot, Dominique; Godin, Pierre; Grizel, Henri; Mialhe, Eric. |
Acid phosphatase activity was cytochemically detected at the ultrastructural level in the protozoan Bonamia ostreae, an intrahemocytic parasite of the flat oyster Ostrea edulis. Lead nitrate was used as capture agent for phosphate liberated during the hydrolysis of the subtrate (cytidine 5' monophosphate). Lead phosphate precipiation, indicative of enzyme activity, was located in membrane-bound organelles corresponding to the cytoplasmic inclusions known as "dense bodies". Acid phosphatase activity level and sodium L-tartrate inhibition were measured spectrophotometrically from a purified parasite suspension. The possible involvement of this enzyme in intracellular survival of B. ostrea is discussed. |
Tipo: Text |
Palavras-chave: Acid phosphate activity; Ostrea edulis; Bonamia ostreae. |
Ano: 1991 |
URL: http://archimer.ifremer.fr/doc/1991/publication-2755.pdf |
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Registros recuperados: 27 | |
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