|
|
|
| Registros recuperados: 36 | |
|
|
| GUIMARÃES,JENNIFER; MARQUES,EDMILSON J.; WANDERLEY-TEIXEIRA,VALÉRIA; ALBUQUERQUE,AURISTELA C. DE; PASSOS,ELIANA M. DOS; SILVA,CÍNTHIA C.M.; TEIXEIRA,ÁLVARO A.C.. |
| This work aimed to evaluate the effects of Metarhizium anisopliae on Diatraea flavipennella and investigate their immune response. Was observed the effect of M. anisopliae against larvae of D. flavipennella sprayed at concentrations of 103, 104, 105 conidia / mL, in which showed differences relative the larval period, extending up to 72.0 days in treatment and 25.0 days in the control. The results for hemocytes revealed that the most frequent cells when sprayed at the concentrations of 103, 105, 107 conidia / mL were the prohemocytes, spherulocytes, plasmatocytes and granulocytes in relation to adipohemocytes and oenocytoids. The level of nitric oxide was different between the control and the concentration 107 spores / mL (24), while the activity of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Entomopathogen; Hemocytes; Histochemistry; Nitric oxide; Phenoloxidases; Sugarcane borer. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652014000401973 |
| |
|
|
| PASSOS,ELIANA M. DOS; WANDERLEY-TEIXEIRA,VALÉRIA; MARQUES,EDMILSON J.; TEIXEIRA,ÁLVARO A.C.; BRAYNER,FÁBIO A.. |
| The present research aimed to elucidate which aspects of immune responses in Diatraea flavipennella are suppressed by the parasitoid Cotesia flavipes, thus, ensuring parasitism success. We investigated the presence of apoptosis in fat body cells through the TUNEL technique. According to the results, reduced levels of nitric oxide and phenoloxidase activity were observed in larvae parasitized for three days, and reduced total number of hemocytes, after three and seven days. An increase in plasmatocytes and decrease in spherulocytes numbers were observed in the differential count on the third day of parasitism. The number of melanized microspheres in parasitized larvae was low and indicated less intense melanization. The ultrastructural analysis confirmed... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Encapsulation; Hemocytes; Humoral response; Parasitoid; Sugarcane Moth Borer (Diatraea saccharalis). |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652014000402013 |
| |
|
| |
|
|
| Falleiros,Ângela Maria Ferreira; Bombonato,Maria Terezinha Siqueira; Gregório,Elisa Aparecida. |
| Six circulating hemocytes cell types from Diatraea saccharalis (Fabricius) (Lepidoptera: Pyralidae) larvae were identified by transmission and scanning electron microscope: prohemocytes (PR), plasmatocytes (PL) granulocytes (GR), spherulocytes (SP), oenocytoids (OE) and vermicytes (VE). The PR was the smallest cell type with a large nucleus, a cytoplasm with few organelles and a homogenous smooth surface. The PL was polymorphic and abundant, with a cytoplasm rich in organelles and a cellular surface with several cytoplasmic projections. The GR was abundant, showing two types of membrane-bounded granules (dense and structutered), glycogen, lipid droplets and a surface with philopodial projections. The SP was a large cell, with a cytoplasm full of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Insect; Lepidoptera; Hemocytes; Ultrastructural Morphology; Differential Hemocyte Count; Morphometry. |
| Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132003000200021 |
| |
|
|
| Bouilly, Karine; Gagnaire, Beatrice; Bonnard, Marc; Thomas-guyon, Helene; Renault, Tristan; Miramand, Pierre; Lapegue, Sylvie. |
| Pacific oysters, Crassostrea gigas, are commonly reared in estuaries where they are exposed to anthropogenic pollution. Much research has been made on the toxicity of cadmium to aquatic organisms because the compound recurrently contaminates their environment. Our study examined the influence of cadmium on aneuploidy level (lowered chromosome number in a percentage of somatic cells) and hemocyte parameters in C. gigas at different stages of life. Adults and juveniles were exposed to two different concentrations of cadmium. The first concentration applied was equivalent to a peak value found in Marennes-Oleron bay (Charente-Maritime, France; 50 ng L-1) and the second was 10 times higher (500 ng L-1). Exposure to 50 ng L-1 cadmium caused a significant... |
| Tipo: Text |
Palavras-chave: Phenoloxidase; Flow cytometry; Hemocytes; Aneuploidy; Crassostrea gigas; Cadmium. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-1687.pdf |
| |
|
|
| Gagnaire, Beatrice; Thomas Guyon, H; Burgeot, Thierry; Renault, Tristan. |
| The shellfish industry is an important economic activity in France, occurring mostly in estuarine zones subject to pollution due to anthropogenic activities. The harmful effects of pollutants on species inhabiting these estuarine zones are not well known. Among marine species, bivalve mollusks---particularly Pacific oyster, Crassostrea gigas-may serve a model of interest. The species is sedentary and filter-feeding, which favors bioaccumulation of pollutants in their tissues. Oysters may be suitable for studies on disturbance by pollutants of physiological activities, among which defense mechanisms are poorly documented in bivalves. In this study, effects of pollutants on hemocyte functions were monitored in Pacific oyster, C. gigas. Hemocytes were exposed... |
| Tipo: Text |
Palavras-chave: Toxicity; Pesticides; PCBs; PAHs; Crassostrea gigas; Pacific oyster; Hemocytes; Flow cytometry; Cellular activities. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-1695.pdf |
| |
|
| |
|
| |
|
|
| Gagnaire, Beatrice; Duchemin, M; Auffret, Mathieu; Thomas-guyon, Helene; Renault, Tristan. |
| Parameters of hemocyte populations have been considered as relevant indicators of bivalve health and are currently used in immunotoxicological studies. Hemocytes in hemolymph can be collected by puncturing either the pericardial cavity or the adductor muscle sinus with a syringe. Flow cytometry is a methodological approach that is increasingly being used in laboratories for the study of hemocyte parameters in aquatic invertebrates. However, various protocols for hemocyte processing in laboratories equipped with different types of cytometers have been published. In this context, two flow cytometers ( EPICS XL4 (R), Beckman Coulter and FacsCalibur (R), Becton Dickinson) and two sites of hemocyte collection ( pericardial cavity and adductor muscle sinus) were... |
| Tipo: Text |
Palavras-chave: Crassostrea gigas; Phagocytosis; Hemocytes; Flow cytometry. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-3898.pdf |
| |
|
|
| Gagnaire, Beatrice; Soletchnik, Patrick; Faury, Nicole; Kerdudou, Nolwenn; Le Moine, Olivier; Renault, Tristan. |
| Internal defence mechanisms of bivalves include the hemocytes which assume several functions. Relationships exist between environmental factors, physiological state of oysters, defence system and pathogens. Hatchery oysters are more and more produced and reared in the field. The characteristics and particularly the defence system of these animals are poorly documented. In this context, two field trials were carried out from May to September 2002 and from April to July 2003 in order to monitor hemocyte parameters of diploid oysters from natural beds and hatchery-produced diploid oysters using flow cytometry. Several hemocyte parameters (cell mortality, granulocyte percentage, phagocytosis, esterase and peroxidase activities) were monitored. For both oyster... |
| Tipo: Text |
Palavras-chave: Hatchery; Natural beds; Diploids; Flow cytometry; Peroxidase activity; Esterase activity; Phagocytosis; Hemocytes; Crassostrea gigas; Pacific oyster. |
| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-3119.pdf |
| |
|
| |
|
|
| Trinkler, Nolwenn; Bardeau, Jean-francois; Marin, Frederic; Labonne, Maylis; Jolivet, Aurelie; Crassous, Philippe; Paillard, Christine. |
| The mineral phase of shell repair in the Manila clam Venerupis philippinarum affected by brown ring disease (BRD) was characterised at various scales and at various stages of shell repair by confocal Raman microspectrometry and scanning electron microscopy. Spherulitic and quadrangular aragonite microstructures associated with polyene pigments were clearly observed. Von Kossa staining showed that at the beginning of shell repair, hemocytes are filled with insoluble calcium carbonate salts in all fluids and then are transported toward the extrapallial fluids and the repair sites. Our analyses suggest that after a Vibrio tapetis attack and BRD deposit some clams rapidly cover the deposit, resulting in a modification in the microstructure, which could be... |
| Tipo: Text |
Palavras-chave: Aragonite; Hemocytes; Shell microstructure; Calcium carbonate; Biomineralization; Mollusc; Raman microspectrometry; Scanning electron microscopy. |
| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00029/14065/11301.pdf |
| |
|
|
| Tirape, Ana; Bacque, Coralie; Brizard, Raphael; Vandenbulcke, Franck; Boulo, Viviane. |
| The work presented here reports the expression of immune-related genes during ontogenesis in the oyster Crassostrea gigar. Expression patterns of 18 selected genes showed that RNAs detected in oocytes and 2-4 cell embryos are of maternal origin and that gene transcription starts early after fertilization. The expression patterns of 4 genes (Cg-timp, Cg-tal, Cg-EcSOD and Drac3) suggested that hemocytes appear in the gastrula-trochophore stages. The localization of Cg-tal expression suggested that hematopoietic cells were derived from vessels and/or artery endothelia cells. Moreover, a bacterial challenge affected the level of expression of genes. Indeed, a change in expression levels was observed for Cg-LBP/BPI, Cg-timp, Drac3 and Cg-MyD88 genes in larval... |
| Tipo: Text |
Palavras-chave: Rel/NF kappa B pathway; Cell proliferation; Hematopoiesis; Mollusk immunity; Hemocytes; Bivalve mollusk. |
| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2612.pdf |
| |
|
| |
|
| |
|
|
| Picot, Sandy; Morga, Benjamin; Faury, Nicole; Chollet, Bruno; Dégremont, Lionel; Travers, Marie-agnes; Renault, Tristan; Arzul, Isabelle. |
| Macroautophagy is a mechanism that is involved in various cellular processes, including cellular homeostasis and innate immunity. This pathway has been described in organisms ranging in complexity from yeasts to mammals, and recent results indicate that it occurs in the mantle of the Pacific oyster, Crassostrea gigas. However, the autophagy pathway has never been explored in the hemocytes of C. gigas, which are the main effectors of its immune system and thus play a key role in the defence of the Pacific oyster against pathogens. To investigate autophagy in oyster hemocytes, tools currently used to monitor this mechanism in mammals, including flow cytometry, fluorescent microscopy and transmission electron microscopy, were adapted and applied to the... |
| Tipo: Text |
Palavras-chave: Autophagosome; Autophagy; Crassostrea gigas; Flow cytometry; Fluorescence microscopy; Hemocytes; Transmission electron microscopy. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00487/59905/63087.pdf |
| |
|
|
| Delaporte, Maryse; Chu, Fu-lin; Langdon, Chris; Moal, Jeanne; Lambert, Christophe; Samain, Jean-francois; Soudant, Philippe. |
| The aim of this study was to assess the effect of dietary eicosapentaenoic acid (20:5n-3) on hemocyte parameters such as hemocyte concentration, phagocytosis, and non-stimulated reactive oxygen species (ROS) production in Pacific oysters Crassostrea gigas, as well on proximate biochemical and fatty acid compositions. One-year-old oysters (C. gigas) were fed T-Isochrysis aff. galbana(T-Iso), which is low in 20:5n-3, either alone or with supplements of a lipid emulsion rich in 20:5n-3 at 1%, 10% or 50% (dry weight of the algal ration) for up to 7 weeks. Changes in gill fatty acid composition demonstrated that the lipid emulsion was well ingested by oysters during the dietary conditioning. Biochemical analysis indicated that oysters fed supplements of 50%... |
| Tipo: Text |
Palavras-chave: Polyunsaturated fatty acids; Immunology; Hemocytes; Eicosapentaenoic acid 20 : 5n 3; Crassostrea gigas; Bivalves. |
| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2604.pdf |
| |
|
|
| Rahmani, Alexandra; Delavat, François; Lambert, Christophe; Le Goic, Nelly; Dabas, Eric; Paillard, Christine; Pichereau, Vianney. |
| Vibrio tapetis is a Gram-negative bacterium that causes infections of mollusk bivalves and fish. The Brown Ring Disease (BRD) is an infection caused by V. tapetis that primarily affects the Manila clam Ruditapes philippinarum. Recent studies have shown that a type IV secretion system (T4SS) gene cluster is exclusively found in strains of V. tapetis pathogenic to clams. However, whether the T4SS is implicated or not during the infection process remains unknown. The aim of this study was to create and characterize a V. tapetis T4SS null mutant, obtained by a near-complete deletion of the virB4 gene, in order to determine the role of T4SS in the development of BRD. This study demonstrated that the T4SS is neither responsible for the loss of hemocyte adhesion... |
| Tipo: Text |
Palavras-chave: Brown Ring Disease; Vibrio tapetis; Ruditapes philippinarum; Hemocytes; Type four secretion system; Rounding phenotype; Colonization; Mutagenesis. |
| Ano: 2021 |
URL: https://archimer.ifremer.fr/doc/00692/80383/83507.pdf |
| |
|
| |
|
|
| Labreuche, Yannick; Le Roux, Frederique; Henry, Joel; Zatylny, Celine; Huvet, Arnaud; Lambert, Christophe; Soudant, Philippe; Mazel, Didier; Nicolas, Jean-louis. |
| Extracellular products (ECPs) of the pathogenic Vibrio aestuarianus 01/32 were previously reported to display lethality in Crassostrea gigas oysters and to cause morphological changes and immunosuppression in oyster hemocytes. To identify the source of this toxicity, biochemical and genetic approaches were developed. ECP protease activity and lethality were shown to be significantly reduced following incubation with metal chelators, suggesting the involvement of a zinc metalloprotease. An open reading frame of 1836 bp encoding a 611-aa metalloprotease (designated yam) was identified. The deduced protein sequence showed high homology to other Vibrio metalloproteases reported to be involved in pathogenicity. To further confirm the role of this enzyme in ECP... |
| Tipo: Text |
Palavras-chave: Vibrio aestuarianus; Metalloprotease; Crassostrea gigas; Oyster; Hemocytes; Extracellular products. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00015/12649/9588.pdf |
| |
| Registros recuperados: 36 | |
|
|
|
