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Bill Pohajdak - One of the best experts on this subject based on the ideXlab platform.
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kinetics of ligand binding to Pseudoterranova decipiens and ascaris suum hemoglobins and to leu 29 tyr sperm whale myoglobin mutant
Journal of Biological Chemistry, 1993Co-Authors: Quentin H Gibson, Bill Pohajdak, R Regan, John S Olson, Theodore E Carver, B Dixon, Pawan K Sharma, Serge N VinogradovAbstract:Abstract The kinetics of binding of O2, CO, and NO to the octameric, two-domain hemoglobins of the parasitic nematodes Pseudoterranova decipiens and Ascaris suum were determined on nanosecond and picosecond time scales using flash photolysis. The two nematode hemoglobins have very similar kinetic properties. On the picosecond time scale, they exhibit an unusual behavior in showing a geminate reaction with oxygen that is biphasic and dependent on the flash intensity. The geminate reaction with NO is also faster and more complete than for sperm whale myoglobin; however, in contrast to the O2 reaction, it is homogeneous. In addition, the oxygen dissociation rate of P. decipiens hemoglobin, 0.0035 s-1, is as low as that of A. suum hemoglobin, 0.004 s-1 (Gibson, Q. H., and Smith, M. H. (1965) Proc. R. Soc. Lond. B Biol. Sci. 163, 206-214). A mutant of sperm whale myoglobin suggested by sequence alignment of the nematode hemoglobins, Leu-29-->Tyr, did not have kinetic properties similar to them.
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Kinetics of ligand binding to Pseudoterranova decipiens and Ascaris suum hemoglobins and to Leu-29-->Tyr sperm whale myoglobin mutant.
Journal of Biological Chemistry, 1993Co-Authors: Quentin H Gibson, Bill Pohajdak, R Regan, John S Olson, Theodore E Carver, B Dixon, Pawan K Sharma, Serge N VinogradovAbstract:Abstract The kinetics of binding of O2, CO, and NO to the octameric, two-domain hemoglobins of the parasitic nematodes Pseudoterranova decipiens and Ascaris suum were determined on nanosecond and picosecond time scales using flash photolysis. The two nematode hemoglobins have very similar kinetic properties. On the picosecond time scale, they exhibit an unusual behavior in showing a geminate reaction with oxygen that is biphasic and dependent on the flash intensity. The geminate reaction with NO is also faster and more complete than for sperm whale myoglobin; however, in contrast to the O2 reaction, it is homogeneous. In addition, the oxygen dissociation rate of P. decipiens hemoglobin, 0.0035 s-1, is as low as that of A. suum hemoglobin, 0.004 s-1 (Gibson, Q. H., and Smith, M. H. (1965) Proc. R. Soc. Lond. B Biol. Sci. 163, 206-214). A mutant of sperm whale myoglobin suggested by sequence alignment of the nematode hemoglobins, Leu-29-->Tyr, did not have kinetic properties similar to them.
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variation in colour of Pseudoterranova decipiens nematoda anisakidae larvae correlates with haemoglobin concentration in the pseudocoelomic fluid
Canadian Journal of Fisheries and Aquatic Sciences, 1993Co-Authors: Brian Dixon, Warwick Charles Kimmins, Bill PohajdakAbstract:Larval sealworm (Pseudoterranova decipiens) were collected from the fillets of Atlantic cod (Gadhus morhua) and the relationship between the colour of the nematodes, which varied from reddish brown to white, and the concentration of haemoglobin in their pseudocoelomic fluid was investigated. The colour of the haemoglobin, which makes up greater than 30% of the protein in the pseudocoelomic fluid, is derived from the heme group. As the heme copurifies with the protein and does not exist in the free form, colour variations in the nematode may, therefore, be due to differences in haemoglobin content. We investigate the possible regulation of levels of this protein and discuss the mechanisms by which this regulation would be achieved.
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isolation and sequencing of a cdna for an unusual hemoglobin from the parasitic nematode Pseudoterranova decipiens
Proceedings of the National Academy of Sciences of the United States of America, 1991Co-Authors: Brian Dixon, Warwick Charles Kimmins, B Walker, Bill PohajdakAbstract:Abstract A cDNA clone encoding a 333-amino acid hemoglobin was isolated from the nematode Pseudoterranova decipiens. The protein contains an 18-amino acid hydrophobic signal sequence and has a calculated mass of 37.6 kDa in the mature form. The predicted protein reveals an internal duplication of a 154-amino acid domain (51% identity). Both domains have significant sequence homology to other primitive hemoglobins, in agreement with a duplication event. Hydrophobicity plots reveal identical strongly hydrophobic regions in each domain, which are potential heme binding sites. This confirms previous suggestions that nematode hemoglobins can have two heme groups per molecule. In addition, each domain contains several conserved histidine motifs that may serve as potential copper binding sites. This result provides further evidence that hemoglobins may have evolved from a primitive cytochrome-like molecule.
Michela Paoletti - One of the best experts on this subject based on the ideXlab platform.
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species specific real time pcr primers probe systems to identify fish parasites of the genera anisakis Pseudoterranova and hysterothylacium nematoda ascaridoidea
Fisheries Research, 2017Co-Authors: Michela Paoletti, Simonetta Mattiucci, Alessandra Colantoni, Arne Levsen, Giuseppe NascettiAbstract:Abstract Ascaridoid nematodes belonging to the genera Anisakis and Pseudoterranova are heteroxenous parasites, involving marine mammals as definitive hosts in their life-cycles, whereas crustaceans (krill), fish and squids acting as intermediate/paratenic hosts. These parasites are considered among the most important biological hazards present in “seafood” products. Indeed, larval stages of the Anisakis and Pseudoterranova have been reported as etiological agents of human infections (anisakidosis). We developed a primers/probe system for the identification of five species of anisakid nematodes belonging to the genera Anisakis (i.e. A. pegreffii and A. simplex (s. s.)), and Pseudoterranova (i.e. P. decipiens (s. s.) , P. krabbei and P. bulbosa) to be used in a real time polymerase chain reaction (RT-PCR) with specific primers based on the mtDNA cox2 gene. Because those anisakid species could be also found in co-infection in some fish species with the raphidascarid nematode Hysterothylacium aduncum , a species-specific primer probe system to be used in RT-PCR for this nematode species was also developed. The detection limit and specificity of the primer/probe systems were evaluated for each of the six nematode species. Singleplex and multiplex RT-PCR protocols were defined and tested. The detection limit of the nematode species tissue was lower than 0.0006 ng/μl. Efficiency ( E ) of primers/probe systems developed was carried out by standard curve; E value varied between 2.015 and 2.11, with respect to a perfect reaction efficiency value of E = 2. Considering the sensibility and quantitative nature of the assays, the new primers/probe system may represent a useful tool for future basic and applied research that focuses on the identification of Anisakis spp., Pseudoterranova spp. and H. aduncum larvae in fish, even in co-infections, with a potential for application in fish farming, fish processing industries, fish markets, and food producers.
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Species-specific Real Time-PCR primers/probe systems to identify fish parasites of the genera Anisakis, Pseudoterranova and Hysterothylacium (Nematoda: Ascaridoidea)
Fisheries Research, 2017Co-Authors: Michela Paoletti, Simonetta Mattiucci, Alessandra Colantoni, Arne Levsen, Giuseppe NascettiAbstract:Abstract Ascaridoid nematodes belonging to the genera Anisakis and Pseudoterranova are heteroxenous parasites, involving marine mammals as definitive hosts in their life-cycles, whereas crustaceans (krill), fish and squids acting as intermediate/paratenic hosts. These parasites are considered among the most important biological hazards present in “seafood” products. Indeed, larval stages of the Anisakis and Pseudoterranova have been reported as etiological agents of human infections (anisakidosis). We developed a primers/probe system for the identification of five species of anisakid nematodes belonging to the genera Anisakis (i.e. A. pegreffii and A. simplex (s. s.)), and Pseudoterranova (i.e. P. decipiens (s. s.) , P. krabbei and P. bulbosa) to be used in a real time polymerase chain reaction (RT-PCR) with specific primers based on the mtDNA cox2 gene. Because those anisakid species could be also found in co-infection in some fish species with the raphidascarid nematode Hysterothylacium aduncum , a species-specific primer probe system to be used in RT-PCR for this nematode species was also developed. The detection limit and specificity of the primer/probe systems were evaluated for each of the six nematode species. Singleplex and multiplex RT-PCR protocols were defined and tested. The detection limit of the nematode species tissue was lower than 0.0006 ng/μl. Efficiency ( E ) of primers/probe systems developed was carried out by standard curve; E value varied between 2.015 and 2.11, with respect to a perfect reaction efficiency value of E = 2. Considering the sensibility and quantitative nature of the assays, the new primers/probe system may represent a useful tool for future basic and applied research that focuses on the identification of Anisakis spp., Pseudoterranova spp. and H. aduncum larvae in fish, even in co-infections, with a potential for application in fish farming, fish processing industries, fish markets, and food producers.
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molecular identification morphological characterization and new insights into the ecology of larval Pseudoterranova cattani in fishes from the argentine coast with its differentiation from the antarctic species p decipiens sp e nematoda anisakidae
Veterinary Parasitology, 2014Co-Authors: Juan T Timi, Michela Paoletti, Roberta Cimmaruta, Ana L Lanfranchi, Ana J Alarcos, Lucas Garbin, Mario Georgenascimento, Diego Rodriguez, Gisela V GiardinoAbstract:Larvae of the genus Pseudoterranova constitute a risk for human health when ingested through raw or undercooked fish. They can provoke pseudoterranovosis in humans, a fish-borne zoonotic disease whose pathogenicity varies with the species involved, making their correct specific identification a necessary step in the knowledge of this zoonosis. Larvae of Pseudoterranova decipiens s.l. have been reported in several fish species from off the Argentine coasts; however, there are no studies dealing with their specific identification in this region. Here, a genetic identification and morphological characterization of larval Pseudoterranova spp. from three fish species sampled from Argentine waters and from Notothenia coriiceps from Antarctic waters was carried out. Larvae were sequenced for their genetic/molecular identification, including the mitochondrial cytochrome c oxidase subunit II (mtDNA cox2), the first (ITS-1) and the second (ITS-2) internal transcribed spacers of the nuclear ribosomal DNA, and compared with all species of the P. decipiens (sensu lato) species complex (sequences available in GenBank). Further, adults of Pseudoterranova spp. from the definitive host, the southern sea lion, Otaria flavescens, from Argentine and Chilean coasts were sequenced at the same genes. The sequences obtained at the ITS-1 and ITS-2 genes from all the larvae examined from fish of Argentine waters, as well as the adult worms, matched 100% the sequences for the species P. cattani. The sequences obtained at mtDNA cox2 gene for Antarctic larvae matched 99% those available in GenBank for the sibling P. decipiens sp. E. Both MP and BI phylogenetic trees strongly supported P. cattani and P. decipiens sp. E as two distinct phylogenetic lineages and depicted the species P. decipiens sp. E as sister taxon to the remaining taxa of the P. decipiens complex. Larval morphometry was similar between specimens of P. cattani from Argentina, but significantly different from those of P. decipiens sp. E, indicating that larval forms can be distinguished based on their morphology. Pseudoterranova cattani is common and abundant in a variety of fish species from Chile, whereas few host species harbour these larvae in Argentina where they show low levels of parasitism. This pattern could arise from a combination of factors, including environmental conditions, density and dietary preferences of definitive hosts and life-cycle pathways of the parasite. Finally, this study revealed that the life-cycle of P. cattani involves mainly demersal and benthic organisms, with a marked preference by large-sized benthophagous fish.
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Additional records of metazoan parasites from Caribbean marine mammals, including genetically identified anisakid nematodes
Parasitology Research, 2009Co-Authors: Marlene M. Colón-llavina, Michela Paoletti, Simonetta Mattiucci, Giuseppe Nascetti, Antonio A. Mignucci-giannoni, Ernest H. WilliamsAbstract:Studies of marine mammal parasites in the Caribbean are scarce. An assessment for marine mammal endo- and ectoparasites from Puerto Rico and the Virgin Islands, but extending to other areas of the Caribbean, was conducted between 1989 and 1994. The present study complements the latter and enhances identification of anisakid nematodes using molecular markers. Parasites were collected from 59 carcasses of stranded cetaceans and manatees from 1994 to 2006, including Globicephala macrorhynchus , Kogia breviceps , Kogia sima , Lagenodelphis hosei , Mesoplodon densirostris , Peponocephala electra , Stenella longirostris , Steno bredanensis , Trichechus manatus . Tursiops truncatus , and Ziphius cavirostris . Sixteen species of endoparasitic helminthes were morphologically identified, including two species of acanthocephalans ( Bolbosoma capitatum , Bolbosoma vasculosum ), nine species of nematodes ( Anisakis sp., Anisakis brevispiculata , Anisakis paggiae , Anisakis simplex , Anisakis typica , Anisakis ziphidarium , Crassicauda anthonyi , Heterocheilus tunicatus , Pseudoterranova ceticola ), two species of cestodes ( Monorygma grimaldi , Phyllobothrium delphini ), and three species of trematodes ( Chiorchis groschafti , Pulmonicola cochleotrema , Monoligerum blairi ). The nematodes belonging to the genus Anisakis recovered in some stranded animals were genetically identified to species level based on their sequence analysis of mitochondrial DNA (629 bp of mtDNA cox 2 ). A total of five new host records and six new geographic records are presented.
Serge N Vinogradov - One of the best experts on this subject based on the ideXlab platform.
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kinetics of ligand binding to Pseudoterranova decipiens and ascaris suum hemoglobins and to leu 29 tyr sperm whale myoglobin mutant
Journal of Biological Chemistry, 1993Co-Authors: Quentin H Gibson, Bill Pohajdak, R Regan, John S Olson, Theodore E Carver, B Dixon, Pawan K Sharma, Serge N VinogradovAbstract:Abstract The kinetics of binding of O2, CO, and NO to the octameric, two-domain hemoglobins of the parasitic nematodes Pseudoterranova decipiens and Ascaris suum were determined on nanosecond and picosecond time scales using flash photolysis. The two nematode hemoglobins have very similar kinetic properties. On the picosecond time scale, they exhibit an unusual behavior in showing a geminate reaction with oxygen that is biphasic and dependent on the flash intensity. The geminate reaction with NO is also faster and more complete than for sperm whale myoglobin; however, in contrast to the O2 reaction, it is homogeneous. In addition, the oxygen dissociation rate of P. decipiens hemoglobin, 0.0035 s-1, is as low as that of A. suum hemoglobin, 0.004 s-1 (Gibson, Q. H., and Smith, M. H. (1965) Proc. R. Soc. Lond. B Biol. Sci. 163, 206-214). A mutant of sperm whale myoglobin suggested by sequence alignment of the nematode hemoglobins, Leu-29-->Tyr, did not have kinetic properties similar to them.
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Kinetics of ligand binding to Pseudoterranova decipiens and Ascaris suum hemoglobins and to Leu-29-->Tyr sperm whale myoglobin mutant.
Journal of Biological Chemistry, 1993Co-Authors: Quentin H Gibson, Bill Pohajdak, R Regan, John S Olson, Theodore E Carver, B Dixon, Pawan K Sharma, Serge N VinogradovAbstract:Abstract The kinetics of binding of O2, CO, and NO to the octameric, two-domain hemoglobins of the parasitic nematodes Pseudoterranova decipiens and Ascaris suum were determined on nanosecond and picosecond time scales using flash photolysis. The two nematode hemoglobins have very similar kinetic properties. On the picosecond time scale, they exhibit an unusual behavior in showing a geminate reaction with oxygen that is biphasic and dependent on the flash intensity. The geminate reaction with NO is also faster and more complete than for sperm whale myoglobin; however, in contrast to the O2 reaction, it is homogeneous. In addition, the oxygen dissociation rate of P. decipiens hemoglobin, 0.0035 s-1, is as low as that of A. suum hemoglobin, 0.004 s-1 (Gibson, Q. H., and Smith, M. H. (1965) Proc. R. Soc. Lond. B Biol. Sci. 163, 206-214). A mutant of sperm whale myoglobin suggested by sequence alignment of the nematode hemoglobins, Leu-29-->Tyr, did not have kinetic properties similar to them.
M D B Burt - One of the best experts on this subject based on the ideXlab platform.
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cell mediated immune response of rainbow trout oncorhynchus mykiss to larval Pseudoterranova decipiens nematoda ascaridoidea following sensitization to live sealworm sealworm extract and nonhomologous extracts
Canadian Journal of Fisheries and Aquatic Sciences, 1993Co-Authors: N R Ramakrishna, M D B Burt, B M MackinnonAbstract:The delaved-type hypersensitivity (DTH) reaction (an in vivo manifestation of cell-mediated immunity) was studied in rainbow trout (Oncorhynchus mykiss) exposed to sealworm Pseudoterranova decipiens infections. Test fish immunized with sealworm extract and live intact worms, were compared with control fish which received either phosphate-buffered saline (negative control) or nonhomologous cestode or nematode antigens (positive control). Test fish immunized with sealworm extract produced a typical DTH reaction to live sealworm, challenge. The DTH reaction was similar to that in mammals and showed lymphoid and mononuclear cell infiltration. The electron microscopical studies revealed the presence of activated macrophages and plasma cells in the reaction zone. The specific response, following immunization with homologous antigens, supports the existence of T-cell function with anamnesis in rainbow trout exposed to sealworm antigens. However, when the test fish were immunized with live sealworms and later cha...
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tissue response of fish to invasion by larval Pseudoterranova decipiens nematoda ascaridoidea
Canadian Journal of Fisheries and Aquatic Sciences, 1991Co-Authors: N R Ramakrishna, M D B BurtAbstract:The histopathology of Pseudoterranova decipiens (L3) in experimentally infected rainbow trout (Oncorhynchus mykiss) and naturally infected Atlantic cod (Gadus morhua) was similar. The chronic granulomatous inflammatory reaction included polymorphonuclear neutrophils, macrophages, lymphocytes, epithelioid cells, and fibroblasts. Giant cells were also found but only in the experimentally infected rainbow trout. Mature capsules around the larvae consisted of an inner layer, composed of macrophages which underwent epithelioid transformation and later gradually degenerated, and an outer layer, composed of fibroblasts and collagen fibres. A layer of lipofuscin was adjacent to the parasite in older cod infections but this was absent in all of the newly formed capsules in the experimentally infected rainbow trout.
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biochemical characterization of third stage larval sealworm Pseudoterranova decipiens nematoda anisakidae in canadian atlantic waters using isoelectric focusing of soluble proteins
Canadian Journal of Fisheries and Aquatic Sciences, 1991Co-Authors: Tracey E Appleton, M D B BurtAbstract:Isoelectric focusing (IEF) was performed on soluble protein extracts from whole specimens of third-stage larval sealworm (Pseudoterranova decipiens) recovered from the musculature of three fish intermediate host species: Atlantic cod (Gadus morhua), sea raven (Hemitripterus americanus), and rainbow smelt (Osmerus mordax). The fish were collected at various sites in the Canadian Atlantic, and IEF revealed the occurrence of two "variants" within what has previously been considered a single, uniform species of P. decipiens in these waters. The larvae were characterized by the absence ("type I" L3's) or presence ("type II" L3's) of a sharp, dark-staining protein band with a mean pl of 6.46 pH units. Type I larvae were predominant at two sites sampled in the lower Bay of Fundy, while type II larvae were predominant at three sites sampled in the Gulf of St. Lawrence region.
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experimental infection of rainbow trout oncorhynchus mykiss with contracaecum osculatum rudolphi 1802 and Pseudoterranova decipiens krabbe 1878 nematoda ascaridoidea
Canadian Journal of Fisheries and Aquatic Sciences, 1990Co-Authors: J W Smith, R Wootten, A E Elarifi, A W Pike, M D B BurtAbstract:The fate of freshly hatched larvae of the marine ascaridoid nematodes Contracaecum osculatum and Pseudoterranova decipiens (from grey seals, Halichoerus grypus, from Scotland and the Canadian Atlantic) was investigated following oral or intraperitoneal introduction into rainbow trout, Oncorhynchus mykiss, maintained at 7–13 °C in fresh water. Neither species appeared to survive for long in the trout alimentary tract following oral introduction; a few larvae were found alive after 2 d but none after 21 d. intraperitoneally, P. decipiens did not survive beyond 21 d, but some C. osculatum exsheathed and developed over several months to lengths over 13 mm, and morphologically and morphometrically resembled third-stage larvae from naturally infected whiting, Merlangius merlangus, from the northern North Sea; no moult was detected. Thus, freshly hatched free-living larvae of C. osculatum are able to develop directly to the third stage in the body cavity of a fish without earlier passage through a crustacean or ...
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serial passage of larval Pseudoterranova decipiens nematoda ascaridoidea in fish
Canadian Journal of Fisheries and Aquatic Sciences, 1990Co-Authors: M D B Burt, C G Likely, J D Campbell, J W SmithAbstract:In one experiment, 24 brook trout (Salvelinus fontinalis) in fresh water at 11 ± 1 °C were each orally infected by intubation with two third-stage larvae of "sealworm" (Pseudoterranova decipiens) harvested from the flesh of sea raven (Hemitripterus americanus) and small Atlantic cod (Gadus morhua). In a second experiment, 27 cod in sea water at 0 °C were each force fed, under anaesthesia, four P. decipiens larvae held in a capelin "purse"; these larvae were harvested from large, commercial size cod. Sequential reinvasion by the same P. decipiens larvae was achieved in both of the serial passage experiments. In brook trout, larvae sequentially reinvaded a maximum of two fish, with larvae of cod origin being the more successful at first passage (62.5%) than those of sea raven origin (31.3 and 37.5%). In cod, larvae also achieved sequential reinvasion of a maximum of two fish; the relatively lower success rates of 22.2% (first passage) and 9.1% (second passage) probably reflect the low temperature (0 °C) at ...
Giuseppe Nascetti - One of the best experts on this subject based on the ideXlab platform.
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species specific real time pcr primers probe systems to identify fish parasites of the genera anisakis Pseudoterranova and hysterothylacium nematoda ascaridoidea
Fisheries Research, 2017Co-Authors: Michela Paoletti, Simonetta Mattiucci, Alessandra Colantoni, Arne Levsen, Giuseppe NascettiAbstract:Abstract Ascaridoid nematodes belonging to the genera Anisakis and Pseudoterranova are heteroxenous parasites, involving marine mammals as definitive hosts in their life-cycles, whereas crustaceans (krill), fish and squids acting as intermediate/paratenic hosts. These parasites are considered among the most important biological hazards present in “seafood” products. Indeed, larval stages of the Anisakis and Pseudoterranova have been reported as etiological agents of human infections (anisakidosis). We developed a primers/probe system for the identification of five species of anisakid nematodes belonging to the genera Anisakis (i.e. A. pegreffii and A. simplex (s. s.)), and Pseudoterranova (i.e. P. decipiens (s. s.) , P. krabbei and P. bulbosa) to be used in a real time polymerase chain reaction (RT-PCR) with specific primers based on the mtDNA cox2 gene. Because those anisakid species could be also found in co-infection in some fish species with the raphidascarid nematode Hysterothylacium aduncum , a species-specific primer probe system to be used in RT-PCR for this nematode species was also developed. The detection limit and specificity of the primer/probe systems were evaluated for each of the six nematode species. Singleplex and multiplex RT-PCR protocols were defined and tested. The detection limit of the nematode species tissue was lower than 0.0006 ng/μl. Efficiency ( E ) of primers/probe systems developed was carried out by standard curve; E value varied between 2.015 and 2.11, with respect to a perfect reaction efficiency value of E = 2. Considering the sensibility and quantitative nature of the assays, the new primers/probe system may represent a useful tool for future basic and applied research that focuses on the identification of Anisakis spp., Pseudoterranova spp. and H. aduncum larvae in fish, even in co-infections, with a potential for application in fish farming, fish processing industries, fish markets, and food producers.
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Species-specific Real Time-PCR primers/probe systems to identify fish parasites of the genera Anisakis, Pseudoterranova and Hysterothylacium (Nematoda: Ascaridoidea)
Fisheries Research, 2017Co-Authors: Michela Paoletti, Simonetta Mattiucci, Alessandra Colantoni, Arne Levsen, Giuseppe NascettiAbstract:Abstract Ascaridoid nematodes belonging to the genera Anisakis and Pseudoterranova are heteroxenous parasites, involving marine mammals as definitive hosts in their life-cycles, whereas crustaceans (krill), fish and squids acting as intermediate/paratenic hosts. These parasites are considered among the most important biological hazards present in “seafood” products. Indeed, larval stages of the Anisakis and Pseudoterranova have been reported as etiological agents of human infections (anisakidosis). We developed a primers/probe system for the identification of five species of anisakid nematodes belonging to the genera Anisakis (i.e. A. pegreffii and A. simplex (s. s.)), and Pseudoterranova (i.e. P. decipiens (s. s.) , P. krabbei and P. bulbosa) to be used in a real time polymerase chain reaction (RT-PCR) with specific primers based on the mtDNA cox2 gene. Because those anisakid species could be also found in co-infection in some fish species with the raphidascarid nematode Hysterothylacium aduncum , a species-specific primer probe system to be used in RT-PCR for this nematode species was also developed. The detection limit and specificity of the primer/probe systems were evaluated for each of the six nematode species. Singleplex and multiplex RT-PCR protocols were defined and tested. The detection limit of the nematode species tissue was lower than 0.0006 ng/μl. Efficiency ( E ) of primers/probe systems developed was carried out by standard curve; E value varied between 2.015 and 2.11, with respect to a perfect reaction efficiency value of E = 2. Considering the sensibility and quantitative nature of the assays, the new primers/probe system may represent a useful tool for future basic and applied research that focuses on the identification of Anisakis spp., Pseudoterranova spp. and H. aduncum larvae in fish, even in co-infections, with a potential for application in fish farming, fish processing industries, fish markets, and food producers.
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Additional records of metazoan parasites from Caribbean marine mammals, including genetically identified anisakid nematodes
Parasitology Research, 2009Co-Authors: Marlene M. Colón-llavina, Michela Paoletti, Simonetta Mattiucci, Giuseppe Nascetti, Antonio A. Mignucci-giannoni, Ernest H. WilliamsAbstract:Studies of marine mammal parasites in the Caribbean are scarce. An assessment for marine mammal endo- and ectoparasites from Puerto Rico and the Virgin Islands, but extending to other areas of the Caribbean, was conducted between 1989 and 1994. The present study complements the latter and enhances identification of anisakid nematodes using molecular markers. Parasites were collected from 59 carcasses of stranded cetaceans and manatees from 1994 to 2006, including Globicephala macrorhynchus , Kogia breviceps , Kogia sima , Lagenodelphis hosei , Mesoplodon densirostris , Peponocephala electra , Stenella longirostris , Steno bredanensis , Trichechus manatus . Tursiops truncatus , and Ziphius cavirostris . Sixteen species of endoparasitic helminthes were morphologically identified, including two species of acanthocephalans ( Bolbosoma capitatum , Bolbosoma vasculosum ), nine species of nematodes ( Anisakis sp., Anisakis brevispiculata , Anisakis paggiae , Anisakis simplex , Anisakis typica , Anisakis ziphidarium , Crassicauda anthonyi , Heterocheilus tunicatus , Pseudoterranova ceticola ), two species of cestodes ( Monorygma grimaldi , Phyllobothrium delphini ), and three species of trematodes ( Chiorchis groschafti , Pulmonicola cochleotrema , Monoligerum blairi ). The nematodes belonging to the genus Anisakis recovered in some stranded animals were genetically identified to species level based on their sequence analysis of mitochondrial DNA (629 bp of mtDNA cox 2 ). A total of five new host records and six new geographic records are presented.
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Pseudoterranova decipiens species A and B (Nematoda, Ascaridoidea): nomenclatural designation, morphological diagnostic characters and genetic markers
Systematic Parasitology, 2000Co-Authors: Lia Paggi, David I Gibson, Simonetta Mattiucci, Giuseppe Nascetti, Rossella Cianchi, Bjorn Berland, Luciano BulliniAbstract:Five genetically distinct and reproductively isolated species have been detected previously within the morphospecies Pseudoterranova decipiens from the Arctic-Boreal, Boreal and Antarctic. Morphological analysis was carried out on male specimens identified by genetic (allozyme) markers, allowing the detection of significant differences at a number of characters between two members of the P. decipiens complex, namely P. decipiens A and B. On the basis of such differences, the nomenclatural designation for the two species is discussed. The names Pseudoterranova krabbei n. sp. and P. decipiens (sensu stricto) are proposed for species A and B, respectively. Morphological and genetic differentiation between the two species is shown using multivariate analysis. Allozyme diagnostic keys for routine identification of the four members of the P. decipiens complex, namely P. decipiens (s.s.), P. krabbei , P. bulbosa and P. azarasi , irrespective of sex and life-history stage, are provided.
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Allozyme and morphological identification of shape Anisakis, Contracaecum and Pseudoterranova from Japanese waters (Nematoda, Ascaridoidea)
Systematic Parasitology, 1998Co-Authors: Simonetta Mattiucci, Kokichi Kikuchi, Noriyuki Sato, Giuseppe Nascetti, Lia Paggi, Hajime Ishikura, Rossella Cianchi, Luciano BulliniAbstract:Allozyme markers were used to identify anisakid nematodes from marine Japanese waters, morphologically assigned to three species complexes: Anisakis simplex (s. l.), Contracaecum osculatum (s. l.) and Pseudoterranova decipiens (s. l.). Samples assigned to A. simplex (s. l.) were found to correspond genetically to A. simplex sensu stricto, those of C. osculatum (s. l.) to C. osculatum A. No morphological characters are yet available to distinguish sibling species of these two complexes. As to the P. decipiens complex, two distinct species were detected: the first corresponded to P. decipiens C, previously recovered in the northern Atlantic, the second to P. decipiens D from Japan. The two species are genetically well differentiated, with five of the 19 loci tested showing distinct fixed alleles. Their reproductive isolation was proved by the lack of hybrids or recombinants in sympatric samples recovered from the same definitive host, Erignathus barbatus. P. decipiens D was found to correspond morphologically to Porrocaecum azarasi, previously considered a synonym of P. decipiens. Accordingly, the name Pseudoterranova azarasi (Yamaguti & Arima, 1942) n. comb. is proposed for P. decipiens D. Similarly, P. decipiens C fits in general morphology, type-locality and host with Ascaris bulbosa, also previously considered a synonym of P. decipiens. The name Pseudoterranova bulbosa (Cobb, 1888) n. comb. is proposed for P. decipiens C.
