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Timothy P Yoshino - One of the best experts on this subject based on the ideXlab platform.
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proteomic analysis of biomphalaria glabrata hemocytes during in vitro encapsulation of schistosoma mansoni Sporocysts
Frontiers in Immunology, 2018Co-Authors: Nathalie Dinguirard, Marilia Gabriela Dos Santos Cavalcanti, Xiaojun Wu, Utibe Bickhamwright, Grzegorz Sabat, Timothy P YoshinoAbstract:Circulating hemocytes of the snail Biomphalaria glabrata, a major intermediate host for the blood fluke Schistosoma mansoni, represent the primary immune effector cells comprising the host’s internal defense system. Within hours of miracidial entry into resistant B. glabrata strains, hemocytes infiltrate around developing Sporocysts forming multi-layered cellular capsules that results in larval death, typically within 24-48 hours post-infection. Using an in vitro model of hemocyte-Sporocyst encapsulation that recapitulates in vivo events, we conducted a comparative proteomic analysis on the responses of hemocytes from inbred B. glabrata strains during the encapsulation of S. mansoni primary Sporocysts. This was accomplished by a combination of Laser-capture microdissection (LCM) to isolate sections of hemocyte capsules both in the presence and absence of Sporocysts, in conjunction with mass spectrometric analyses to establish protein expression profiles. Comparison of susceptible NMRI snail hemocytes in the presence and absence of Sporocysts revealed a dramatic downregulation of proteins in during larval encapsulation, especially those involved in protein/CHO metabolism, immune-related, redox and signaling pathways. One of 4 upregulated proteins was arginase, competitor of nitric oxide synthetase and inhibitor of larval-killing NO production. By contrast, when compared to control capsules, Sporocyst-encapsulating hemocytes of resistant BS-90 B. glabrata exhibited a more balanced profile with enhanced expression of shared proteins involved in protein synthesis/processing, immunity, and redox, and unique expression of anti-microbial/anti-parasite proteins. A final comparison of NMRI and BS-90 host hemocyte responses to co-cultured Sporocysts demonstrated a decrease or downregulation of 77% of shared proteins by NMRI cells during encapsulation compared to those of the BS-90 strain, including lipopolysaccharide-binding protein, thioredoxin reductase 1 and hemoglobins 1 and 2. Overall, using this in vitro model, results of our proteomic analyses demonstrate striking differences in proteins expressed by susceptible NMRI and resistant BS-90 snail hemocytes to S. mansoni Sporocysts during active encapsulation, with NMRI hemocytes exhibiting extensive downregulation of protein expression and a lower level of constitutively expressed immune-relevant proteins (e.g., FREP2) compared to BS-90. Our data suggest that snail strain differences in hemocyte protein expression during the encapsulation process account for observed differences in their cytotoxic capacity to interact with and kill Sporocysts.
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Table_2_Proteomic Analysis of Biomphalaria glabrata Hemocytes During in vitro Encapsulation of Schistosoma mansoni Sporocysts.XLSX
2018Co-Authors: Nathalie Dinguirard, Marilia Gabriela Dos Santos Cavalcanti, Grzegorz Sabat, Utibe Bickham-wright, Timothy P YoshinoAbstract:Circulating hemocytes of the snail Biomphalaria glabrata, a major intermediate host for the blood fluke Schistosoma mansoni, represent the primary immune effector cells comprising the host's internal defense system. Within hours of miracidial entry into resistant B. glabrata strains, hemocytes infiltrate around developing Sporocysts forming multi-layered cellular capsules that results in larval death, typically within 24–48 h post-infection. Using an in vitro model of hemocyte-Sporocyst encapsulation that recapitulates in vivo events, we conducted a comparative proteomic analysis on the responses of hemocytes from inbred B. glabrata strains during the encapsulation of S. mansoni primary Sporocysts. This was accomplished by a combination of Laser-capture microdissection (LCM) to isolate sections of hemocyte capsules both in the presence and absence of Sporocysts, in conjunction with mass spectrometric analyses to establish protein expression profiles. Comparison of susceptible NMRI snail hemocytes in the presence and absence of Sporocysts revealed a dramatic downregulation of proteins in during larval encapsulation, especially those involved in protein/CHO metabolism, immune-related, redox and signaling pathways. One of 4 upregulated proteins was arginase, competitor of nitric oxide synthetase and inhibitor of larval-killing NO production. By contrast, when compared to control capsules, Sporocyst-encapsulating hemocytes of resistant BS-90 B. glabrata exhibited a more balanced profile with enhanced expression of shared proteins involved in protein synthesis/processing, immunity, and redox, and unique expression of anti-microbial/anti-parasite proteins. A final comparison of NMRI and BS-90 host hemocyte responses to co-cultured Sporocysts demonstrated a decrease or downregulation of 77% of shared proteins by NMRI cells during encapsulation compared to those of the BS-90 strain, including lipopolysaccharide-binding protein, thioredoxin reductase 1 and hemoglobins 1 and 2. Overall, using this in vitro model, results of our proteomic analyses demonstrate striking differences in proteins expressed by susceptible NMRI and resistant BS-90 snail hemocytes to S. mansoni Sporocysts during active encapsulation, with NMRI hemocytes exhibiting extensive downregulation of protein expression and a lower level of constitutively expressed immune-relevant proteins (e.g., FREP2) compared to BS-90. Our data suggest that snail strain differences in hemocyte protein expression during the encapsulation process account for observed differences in their cytotoxic capacity to interact with and kill Sporocysts.
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Polypeptides synthesized in vitro by Biomphalaria glabrata hemocytes bind to Schistosoma mansoni primary Sporocysts
Journal of invertebrate pathology, 1993Co-Authors: Michael J. Lodes, Timothy P YoshinoAbstract:Abstract In vitro labeled polypeptides secreted by schistosome-susceptible and -resistant Biomphalaria glabrata were tested for their ability to bind the surface tegument of Schistosoma mansoni primary (=mother) Sporocysts. Out of a complex pattern of SDS-PAGE-separated hemocyte polypeptides, only two (19 and 46 kDa) bound to Sporocysts. The 19-kDa polypeptide consistently bound to both live and fixed Sporocysts, although fixed larvae usually bound more than living Sporocysts. The 46-kDa component bound primarily to fixed Sporocysts. A similar pattern of binding was seen when Sporocysts were exposed to polypeptides secreted into culture medium by both resistant and susceptible snail hemocytes. However, previous work indicates that Sporocyst secretory products, in the presence of homologous snail plasma components, can differentially influence the quantity of these two polypeptides. Therefore, it is hypothesized that "regulation" of the interaction of snail hemocyte polypeptides with the parasite may lie in the Sporocyst-mediated differential effect on synthesis and/or secretion of the 19-and 46-kDa polypeptides by hemocytes of these two snail strains. Thus, the hemocyte polypeptides reported in this study may represent potential mediators of self/non-selfrecognition or hemocyte activation in the B. glabrata internal defense system.
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Tegumental surface modulation in Schistosoma mansoni primary Sporocysts in response to ligand binding.
Parasite immunology, 1991Co-Authors: Terry S. Dunn, Timothy P YoshinoAbstract:Summary The clearance of host molecules from the surface of a parasite constitutes a potential immune evasive strategy. The possibility that certain ligands. when bound to the tegument of Schistosoma mansoni primary Sporocysts, could induce such a modulating effect was investigated. Live, in vitro cultured primary Sporocysts were first treated with either snail host Biomphataria glabrata plasma, an anti-Sporocyst monoclonal antibody (MoAb III-1), or concanavalin A (con A). The capacity of these primary ligands to produce a modulating effect alone, or when subsequently crosslinked by secondary or tertiary ligands, was measured using quantitative fluorescence microscopy. Snail plasma alone, or plasma crosslinked at the Sporocyst surface with a mouse anti-plasma MoAb had little or no modulating effect. However, a tertiary level of ligand crosslinking with an anti-mouse IgG antibody produced an average 1.8-fold decrease in surface fluorescence within 1 h post-labelling. The anti-Sporocyst MoAb III-1 also required secondary antibody reactivity to induce an average 1.5-fold decrease in MoAb III-1 recognized epitopes. Sporocysts labelled wilh con A crosslinkcd by secondary and tertiary ligands showed inconsistent modulation, with a 1.5-fold decrease in fluorescence in one out of three replicates. Overall, however, analysis of combined data revealed no significant effect of tertiary ligand level crosslinkage on modulation of con A-tegumental receptor complexes. In contrast, con A binding alone to tegumental determinants induced a small, but significant, reduction in surface con A complexes. Modulation of ligand-receptor complexes on the Sporocyst tegumental membrane appears to be an energy-requiring event, since clearance of surface complexes was inhibited in the presence of sodium azidc and/or sodium iodoacetate, or when larvae were incubated at 4°C. It is concluded that alterations in sporocysl tegumenlal surface components may be triggered by specific (but as yet undefined) signals. Sporocysts are capable of exhibiting different responses depending on the nature of the binding signal and reactive tegumental receptor, and the degree of ligand crosslinkage.
Wanderley De Souza - One of the best experts on this subject based on the ideXlab platform.
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The morphology of Sporocysts of eurytrema coelomaticum (trematoda, dicrocoeliidae)
The biologist, 2012Co-Authors: Jairo Pinheiro, Solange Viana Paschoal Blanco Brandolini, Wanderley De Souza, Daniele O. Franco Acuña, Aleksandra Oliveira Menezes, Renato Augusto DamattaAbstract:Eurytrema coelomaticum is a fluke that infects ruminants in South America, Europe and Asia. The morphology of the mother and daughter Sporocysts of E. coelomaticum obtained from Bradybaena similaris, the first intermediate host, is described for the first time by light and scanning electron microscopy. The intermediate host was exposed to E. coelomaticum eggs and after 30 days the mother Sporocyst was found in the coelom adhered to the intestine wall. This Sporocyst was a rounded or elongated mass (0.1078mm), with numerous germinal balls in it, and a folded tegument with no specializations. The daughter Sporocysts obtained following dissection of infected snails have varied shape, one hollow tapered region with many transversal and longitudinal striations, named anterior end. The expelled daughter Sporocyst presented an oval sac-like central region with a small anterior and a posterior longer filament-like prolongation. The measures of the expelled Sporocysts are presented and compared to previous descriptions. The mother Sporocyst was attached to the coelome of the intestine wall of intermediate snail host B. similaris, intimately adhered in some regions. It presents a highly folded tegument with granules and the body wall was composed by an outer syncitial layer, basal lamina, and circular and longitudinal muscle layer. Below was the cell body (cyton) with the nucleus. The daughter Sporocysts obtained by dissection exhibited many granules and secretory vesicle in the outer layer indicating an intense secretory activity. The body wall presented the same layers of the mother Sporocysts, but the outer syncitial layer invaginated and an amorphous layer was present between the syncitial and circular muscle layers. The protonephridial excretory system was viewed. The anterior and posterior end of the expelled Sporocyst exhibit a degenerated structure, but biological activity still occurred in these regions. The swollen middle of the body was filled by a lamellar structure formed by degenerating membranes, but the excretory system was preserved. The endocyst wall was fibrilar and filled by cercariae and amorphous, membranous and secretory material inside it. By the first time, the morphology of E. coelomaticum Sporocysts was deeply analyzed using different microscopic techniques, elucidating points of their structure, being an important tool to the taxonomy of this species of trematode.
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Ultrastructure of the Sporocysts of Eurytrema coelomaticum (Giard Et Billet, 1892) Looss, 1907.
Veterinary parasitology, 2011Co-Authors: Jairo Pinheiro, Daniele Oliveira Franco-acuña, Aleksandra Oliveira-menezes, Solange Viana Paschoal Blanco Brandolini, Wanderley De Souza, Renato Augusto DamattaAbstract:The digenetic trematode Eurytrema coelomaticum is a parasite of pancreatic ducts of ruminants. The ultrastructure of the mother and daughter Sporocysts of E. coelomaticum was analyzed. The mother Sporocyst was attached to the coelome of the intestine wall of intermediate snail host Bradybaena similaris, intimately adhered in some regions. It presents a highly folded tegument with granules and the body wall was composed by an outer syncitial layer, basal lamina, and circular and longitudinal muscle layer. Below was the cell body (cyton) with the nucleus. The daughter Sporocysts obtained by dissection exhibited many granules and secretory vesicle in the outer layer indicating an intense secretory activity. The body wall presented the same layers of the mother Sporocysts, but the outer syncitial layer invaginated and an amorphous layer was present between the syncitial and circular muscle layers. The protonephridial excretory system was viewed. The anterior and posterior end of the expelled Sporocyst exhibit a degenerated structure, but biological activity still occurred in these regions. The swollen middle of the body was filled by a lamellar structure formed by degenerating membranes, but the excretory system was preserved. The endocyst wall was fibrilar and filled by cercariae and amorphous, membranous and secretory material inside it. These results were discussed.
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Light and scanning electron microscopy of Sporocysts of Eurytrema coelomaticum (Giard et Billet, 1892) Looss, 1907.
Veterinary parasitology, 2010Co-Authors: Daniele Oliveira Franco-acuña, Jairo Pinheiro, Aleksandra Oliveira-menezes, Solange Viana Paschoal Blanco Brandolini, Renato Augusto Damatta, Wanderley De SouzaAbstract:Eurytrema coelomaticum is a fluke that infects ruminants in South America, Europe and Asia. The morphology of the mother and daughter Sporocysts of E. coelomaticum obtained from Bradybaena similaris, the first intermediate host, is described for the first time by light and scanning electron microscopy. The intermediate host was exposed to E. coelomaticum eggs and after 30 days the mother Sporocyst was found in the coelom adhered to the intestine wall. This Sporocyst was a rounded or elongated mass (0.1078 mm), with numerous germinal balls in it, and a folded tegument with no specializations. The daughter Sporocysts obtained following dissection of infected snails have varied shape, one hollow tapered region with many transversal and longitudinal striations, named anterior end. The expelled daughter Sporocyst presented an oval sac-like central region with a small anterior and a posterior longer filament-like prolongation. The measures of the expelled Sporocysts are presented and compared to previous descriptions.
E C Greiner - One of the best experts on this subject based on the ideXlab platform.
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Sporocyst size of isolates of Sarcocystis shed by the Virginia opossum (Didelphis virginiana).
Veterinary parasitology, 2001Co-Authors: M A Cheadle, J B Dame, E C GreinerAbstract:The Virginia opossum (Didelphis virginiana) is a definitive host for multiple Sarcocystis species including Sarcocystis neurona, one of the causative agents of equine protozoal myeloencephalitis (EPM), a severe, neuromuscular disease of horses. Size and morphologic characteristics of isolates of Sarcocystis shed by the opossum were examined to determine if differences were useful in discriminating between the isolates and/or species. Collections of Sporocysts from 17 opossums were molecularly characterized and measured using an ocular micrometer. The mean Sporocyst size of isolates of S. neurona was 10.7 microm x 7.0 microm, Sarcocystis falcatula 11.0 microm x 7.1 microm, Sarcocystis speeri 12.2 microm x 8.8 microm, 1085-like isolate 10.9 microm x 6.8 microm, and 3344-like isolate 19.4 microm x 10.5 microm. The length and width of S. speeri were statistically different (p < 0.05) from the Sporocysts of other types. The length of S. neurona and S. falcatula Sporocysts were statistically different (p < 0.05) from each other and the width of S. falcatula and 1085 differed (p < 0.05). The fifth Sporocyst type (3344) was observed, but due to pronounced morphological characteristics, statistical analysis was not performed. There was no consistent difference between the taxa based on internal structure of the Sporocyst.
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Evaluation of the shedding of Sarcocystis falcatula Sporocysts in experimentally infected Virginia opossums (Didelphis virginiana).
Veterinary parasitology, 2001Co-Authors: R A Porter, J B Dame, P E Ginn, E C GreinerAbstract:Five Virginia opossums (Didelphis virginiana) were fed muscles of brown-headed cowbirds (Molothrus ater) containing sarcocysts of Sarcocystis falcatula. Shedding of Sporocysts was confirmed in all five opossums by fecal flotation. Counts were conducted daily for 2 weeks and then biweekly until the animals were euthanized and necropsied. The average prepatent period was 9.8 (7-16) days. The number of Sporocysts shed varied greatly between the opossums with maximum mean shedding occurring at 71.6 (26-112) days post-infection (DPI). Average Sporocyst production was 1480 Sporocysts/gram of feces (SPG). Maximum output was 37,000 SPG. Average fecal yield in captivity was 17.5g of feces/day. Opossums shed 25,900 Sporocysts/day (average) and a maximum of 647,500 Sporocysts/day. All opossums shed Sporocysts until time of euthanasia (46-200 DPI). Histologically, numerous Sporocysts were present in the lamina propria at necropsy, primarily in the proximal half of the small intestine. Sporocysts were generally in clusters within the lamina propria of the luminal two-thirds of the villi. Sporocysts were found less frequently in the epithelium. No evidence of ongoing gametogony or other development was evident.
Renato Augusto Damatta - One of the best experts on this subject based on the ideXlab platform.
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The morphology of Sporocysts of eurytrema coelomaticum (trematoda, dicrocoeliidae)
The biologist, 2012Co-Authors: Jairo Pinheiro, Solange Viana Paschoal Blanco Brandolini, Wanderley De Souza, Daniele O. Franco Acuña, Aleksandra Oliveira Menezes, Renato Augusto DamattaAbstract:Eurytrema coelomaticum is a fluke that infects ruminants in South America, Europe and Asia. The morphology of the mother and daughter Sporocysts of E. coelomaticum obtained from Bradybaena similaris, the first intermediate host, is described for the first time by light and scanning electron microscopy. The intermediate host was exposed to E. coelomaticum eggs and after 30 days the mother Sporocyst was found in the coelom adhered to the intestine wall. This Sporocyst was a rounded or elongated mass (0.1078mm), with numerous germinal balls in it, and a folded tegument with no specializations. The daughter Sporocysts obtained following dissection of infected snails have varied shape, one hollow tapered region with many transversal and longitudinal striations, named anterior end. The expelled daughter Sporocyst presented an oval sac-like central region with a small anterior and a posterior longer filament-like prolongation. The measures of the expelled Sporocysts are presented and compared to previous descriptions. The mother Sporocyst was attached to the coelome of the intestine wall of intermediate snail host B. similaris, intimately adhered in some regions. It presents a highly folded tegument with granules and the body wall was composed by an outer syncitial layer, basal lamina, and circular and longitudinal muscle layer. Below was the cell body (cyton) with the nucleus. The daughter Sporocysts obtained by dissection exhibited many granules and secretory vesicle in the outer layer indicating an intense secretory activity. The body wall presented the same layers of the mother Sporocysts, but the outer syncitial layer invaginated and an amorphous layer was present between the syncitial and circular muscle layers. The protonephridial excretory system was viewed. The anterior and posterior end of the expelled Sporocyst exhibit a degenerated structure, but biological activity still occurred in these regions. The swollen middle of the body was filled by a lamellar structure formed by degenerating membranes, but the excretory system was preserved. The endocyst wall was fibrilar and filled by cercariae and amorphous, membranous and secretory material inside it. By the first time, the morphology of E. coelomaticum Sporocysts was deeply analyzed using different microscopic techniques, elucidating points of their structure, being an important tool to the taxonomy of this species of trematode.
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Ultrastructure of the Sporocysts of Eurytrema coelomaticum (Giard Et Billet, 1892) Looss, 1907.
Veterinary parasitology, 2011Co-Authors: Jairo Pinheiro, Daniele Oliveira Franco-acuña, Aleksandra Oliveira-menezes, Solange Viana Paschoal Blanco Brandolini, Wanderley De Souza, Renato Augusto DamattaAbstract:The digenetic trematode Eurytrema coelomaticum is a parasite of pancreatic ducts of ruminants. The ultrastructure of the mother and daughter Sporocysts of E. coelomaticum was analyzed. The mother Sporocyst was attached to the coelome of the intestine wall of intermediate snail host Bradybaena similaris, intimately adhered in some regions. It presents a highly folded tegument with granules and the body wall was composed by an outer syncitial layer, basal lamina, and circular and longitudinal muscle layer. Below was the cell body (cyton) with the nucleus. The daughter Sporocysts obtained by dissection exhibited many granules and secretory vesicle in the outer layer indicating an intense secretory activity. The body wall presented the same layers of the mother Sporocysts, but the outer syncitial layer invaginated and an amorphous layer was present between the syncitial and circular muscle layers. The protonephridial excretory system was viewed. The anterior and posterior end of the expelled Sporocyst exhibit a degenerated structure, but biological activity still occurred in these regions. The swollen middle of the body was filled by a lamellar structure formed by degenerating membranes, but the excretory system was preserved. The endocyst wall was fibrilar and filled by cercariae and amorphous, membranous and secretory material inside it. These results were discussed.
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Light and scanning electron microscopy of Sporocysts of Eurytrema coelomaticum (Giard et Billet, 1892) Looss, 1907.
Veterinary parasitology, 2010Co-Authors: Daniele Oliveira Franco-acuña, Jairo Pinheiro, Aleksandra Oliveira-menezes, Solange Viana Paschoal Blanco Brandolini, Renato Augusto Damatta, Wanderley De SouzaAbstract:Eurytrema coelomaticum is a fluke that infects ruminants in South America, Europe and Asia. The morphology of the mother and daughter Sporocysts of E. coelomaticum obtained from Bradybaena similaris, the first intermediate host, is described for the first time by light and scanning electron microscopy. The intermediate host was exposed to E. coelomaticum eggs and after 30 days the mother Sporocyst was found in the coelom adhered to the intestine wall. This Sporocyst was a rounded or elongated mass (0.1078 mm), with numerous germinal balls in it, and a folded tegument with no specializations. The daughter Sporocysts obtained following dissection of infected snails have varied shape, one hollow tapered region with many transversal and longitudinal striations, named anterior end. The expelled daughter Sporocyst presented an oval sac-like central region with a small anterior and a posterior longer filament-like prolongation. The measures of the expelled Sporocysts are presented and compared to previous descriptions.
Daniele Oliveira Franco-acuña - One of the best experts on this subject based on the ideXlab platform.
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Ultrastructure of the Sporocysts of Eurytrema coelomaticum (Giard Et Billet, 1892) Looss, 1907.
Veterinary parasitology, 2011Co-Authors: Jairo Pinheiro, Daniele Oliveira Franco-acuña, Aleksandra Oliveira-menezes, Solange Viana Paschoal Blanco Brandolini, Wanderley De Souza, Renato Augusto DamattaAbstract:The digenetic trematode Eurytrema coelomaticum is a parasite of pancreatic ducts of ruminants. The ultrastructure of the mother and daughter Sporocysts of E. coelomaticum was analyzed. The mother Sporocyst was attached to the coelome of the intestine wall of intermediate snail host Bradybaena similaris, intimately adhered in some regions. It presents a highly folded tegument with granules and the body wall was composed by an outer syncitial layer, basal lamina, and circular and longitudinal muscle layer. Below was the cell body (cyton) with the nucleus. The daughter Sporocysts obtained by dissection exhibited many granules and secretory vesicle in the outer layer indicating an intense secretory activity. The body wall presented the same layers of the mother Sporocysts, but the outer syncitial layer invaginated and an amorphous layer was present between the syncitial and circular muscle layers. The protonephridial excretory system was viewed. The anterior and posterior end of the expelled Sporocyst exhibit a degenerated structure, but biological activity still occurred in these regions. The swollen middle of the body was filled by a lamellar structure formed by degenerating membranes, but the excretory system was preserved. The endocyst wall was fibrilar and filled by cercariae and amorphous, membranous and secretory material inside it. These results were discussed.
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Light and scanning electron microscopy of Sporocysts of Eurytrema coelomaticum (Giard et Billet, 1892) Looss, 1907.
Veterinary parasitology, 2010Co-Authors: Daniele Oliveira Franco-acuña, Jairo Pinheiro, Aleksandra Oliveira-menezes, Solange Viana Paschoal Blanco Brandolini, Renato Augusto Damatta, Wanderley De SouzaAbstract:Eurytrema coelomaticum is a fluke that infects ruminants in South America, Europe and Asia. The morphology of the mother and daughter Sporocysts of E. coelomaticum obtained from Bradybaena similaris, the first intermediate host, is described for the first time by light and scanning electron microscopy. The intermediate host was exposed to E. coelomaticum eggs and after 30 days the mother Sporocyst was found in the coelom adhered to the intestine wall. This Sporocyst was a rounded or elongated mass (0.1078 mm), with numerous germinal balls in it, and a folded tegument with no specializations. The daughter Sporocysts obtained following dissection of infected snails have varied shape, one hollow tapered region with many transversal and longitudinal striations, named anterior end. The expelled daughter Sporocyst presented an oval sac-like central region with a small anterior and a posterior longer filament-like prolongation. The measures of the expelled Sporocysts are presented and compared to previous descriptions.
