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Gabriela Hrčková - One of the best experts on this subject based on the ideXlab platform.
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Species delimitation based on mtDNA genes suggests the occurrence of new species of Mesocestoides in the Mediterranean region
Parasites & Vectors, 2018Co-Authors: Antonio Varcasia, Gabriela Hrčková, Daria Sanna, Marco Casu, Samia Lahmar, Giorgia Dessì, Anna Paola Pipia, Claudia Tamponi, Gabriella Gaglio, Domenico OtrantoAbstract:Background This study is the first contribution to the molecular taxonomy of Mesocestoides spp. from domestic and wild carnivores in the Mediterranean area. A total of 13 adult worms and 13 larval stages of Mesocestoides spp. were collected from domestic and wild carnivore hosts in Italy and Tunisia. Samples collected in the Slovak Republic were used as comparative samples from outside the Mediterranean. The genes cytochrome c oxidase subunit 1 ( cox 1) and NADH dehydrogenase subunit 1 ( nad 1) of the mitochondrial genome were used as molecular markers to investigate the presence of cryptic Mesocestoides species in the area analysed. Results Results were consistent in showing three well-supported clusters of Mesocestoides spp. in southern Italy and Tunisia, which were strongly divergent from Mesocestoides litteratus , M. corti and M. lineatus. High levels of genetic variation and no evidence of geographical structuring was found between the clusters. Conclusions Considering the low dispersal capability of the intermediate hosts of Mesocestoides spp., the lack of geographical structuring among the Mediterranean regions could be due to a high potential for dispersion of the definitive hosts. This study provides a foundation for future formal descriptions of new species of the genus Mesocestoides in the Mediterranean area.
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In vitro culture of Mesocestoides corti metacestodes and isolation of immunomodulatory excretory-secretory products.
Parasite immunology, 2016Co-Authors: Emilia Vendelova, Gabriela Hrčková, Manfred B. Lutz, Klaus Brehm, Justin Komguep NonoAbstract:Cestode-mediated diseases hold the interesting feature of persisting metacestode larvae dwelling within the host tissues, in the midst of the immune response. Excretory-secretory (ES) products of the metacestode larval stage modulate the host immune response and modify the outcome of the disease. Therefore, isolation and analysis of axenic metacestode ES products are crucial to study their properties. Here, we report the development of a system for long-term in vitro cultivation of the metacestode of the parasitic cestode Mesocestoides corti (syn. Mesocestoides vogae). Although feeder cells and host serum supported the early growth of the parasite, long-term survival was not dependent on host serum or host-derived factors enabling the collection of parasite released products in serum-free medium. Functionally, these axenic ES products recapitulated M. corti tetrathyridia's ability to inhibit LPS-driven IL-12p70 secretion by dendritic cells. Thus, our new axenic culture system will simplify the identification and characterization of M. corti-derived immunomodulatory factors that will indirectly enable the identification and characterization of corresponding factors in the metacestode larvae of medically relevant cestodes such as Echinococcus multilocularis that are not yet amenable to serum-free cultivation.
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molecular and morphological circumscription of mesocestoides tapeworms from red foxes vulpes vulpes in central europe
Parasitology, 2011Co-Authors: Gabriela Hrčková, M Miterpakova, Anne Oconnor, V Snabel, Peter D OlsonAbstract:: Here we examine 3157 foxes from 6 districts of the Slovak Republic in order to determine for the first time the distribution, prevalence and identity of Mesocestodes spp. endemic to this part of central Europe. During the period 2001-2006, an average of 41.9% of foxes were found to harbour Mesocestoides infections. Among the samples we confirmed the widespread and common occurrence of M. litteratus (Batsch, 1786), and report the presence, for the first time, of M. lineatus (Goeze, 1782) in the Slovak Republic, where it has a more restricted geographical range and low prevalence (7%). Using a combination of 12S rDNA, CO1 and ND1 mitochondrial gene sequences together with analysis of 13 morphometric characters, we show that the two species are genetically distinct and can be differentiated by discrete breaks in the ranges of the male and female reproductive characters, but not by the more commonly examined characters of the scolex and strobila. Estimates of interspecific divergence within Mesocestoides ranged from 9 to 18%, whereas intraspecific variation was less than 2%, and phylogenetic analyses of the data showed that despite overlapping geographical ranges, the two commonly reported European species are not closely related, with M. litteratus more closely allied to North American isolates of Mesocestoides than to M. lineatus. We confirm that morphological analysis of reproductive organs can be used to reliably discriminate between these often sympatric species obtained from red foxes.
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antibody response in mice infected with mesocestoides vogae syn mesocestoides corti tetrathyridia after treatment with praziquantel and liposomised glucan
Parasitology Research, 2007Co-Authors: Gabriela Hrčková, Samuel Velebný, Grigorij KoganAbstract:The therapeutic effect of praziquantel (PZQ) involves synergy with the humoral immune response during helminth infections, which is modulated by parasitic antigens. During experimental murine infections with the larval stage of cestoda Mesocestoides vogae (syn. M. corti), dynamic changes in the IgG and IgM antibody serum levels to both soluble somatic and secretory larval antigens were investigated after administration of PZQ alone and after its co-administration with the immunomodulator (l→3)-β-d-glucan entrapped in liposomes (lip.glucan).
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pharmacological characterisation of neuropeptide f npf induced effects on the motility of mesocestoides corti syn mesocestoides vogae larvae
International Journal for Parasitology, 2004Co-Authors: Gabriela Hrčková, Samuel Velebný, D W Halton, Tim A Day, Aaron G MauleAbstract:Neuropeptide F is the most abundant neuropeptide in parasitic flatworms and is analogous to vertebrate neuropeptide Y. This paper examines the effects of neuropeptide F on tetrathyridia of the cestode Mesocestoides vogae and provides preliminary data on the signalling mechanisms employed. Neuropeptide F ( $ 10 mM) had profound excitatory effects on larval motility in vitro. The effects were insensitive to high concentrations (1 mM) of the anaesthetic procaine hydrochloride suggesting extraneuronal sites of action. Neuropeptide F activity was not significantly blocked by a FMRFamide-related peptide analog (GNFFRdFamide) that was found to inhibit GNFFRFamide-induced excitation indicating the occurrence of distinct neuropeptide F and FMRFamide-related peptide receptors. Larval treatment with guanosine 5 0 -O-(2-thiodiphosphate) trilithium salt prior to the addition of neuropeptide F completely abolished the excitatory effects indicating the involvement of G-proteins and a G-protein coupled receptor in neuropeptide F activity. Addition of guanosine 5 0 -O-(2-thiodiphosphate) following neuropeptide F had limited inhibitory effects consistent with the activation of a signalling cascade by the neuropeptide. With respect to Ca 2þ involvement in neuropeptide F-induced excitation of M. vogae larvae, the L-type Ca 2þ -channel blockers verapamil and nifedipine both abolished neuropeptide F activity as did high Mg þ concentrations and drugs which blocked sarcoplasmic reticulum Ca 2þ activated Ca 2þ -channels (ryanodine) and sarcoplasmic reticulum Ca 2þ pumps (cyclopiazonic acid). Therefore, both extracellular and intracellular Ca 2þ is important for neuropeptide F excitation in M. vogae. With resepct to second messengers, the protein kinase C inhibitor chelerythrine chloride and the adenylate cyclase inhibitor MDL-2330A both abolished neuropeptide F-induced excitation. The involvement of a signalling pathway that involves protein kinase C was further supported by the fact that phorbol-12-myristate-13-acetate, known to directly activate protein kinase C, had direct excitatory effects on larval motility. Although neuropeptide F is structurally analogous to neuropeptide Y, its mode-of-action in flatworms appears quite distinct from the common signalling mechanism seen in vertebrates. q 2003 on behalf of Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.
Sadao Nogami - One of the best experts on this subject based on the ideXlab platform.
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case report first confirmed case of canine peritoneal larval cestodiasis caused by mesocestoides vogae syn m corti in japan
Veterinary Parasitology, 2014Co-Authors: Takuya Kashiide, Yoshiki Yamaya, Aya Uwasawa, Ai Miyoshi, Jun Matsumoto, Toshihiro Watari, Kazuo Yamada, Sadao NogamiAbstract:Abstract Canine peritoneal larval cestodiasis (CPLC) is an unusual parasitic disease in dogs that is caused by asexual proliferation of larval Mesocestoides . A 12 year-old spayed Shetland sheepdog with abdominal distension was referred to the Animal Medical Center at Nihon University, Japan. The presence of ascites was confirmed by abdominal ultrasonography and X-ray imaging. In addition, a number of parasites were observed in the ascitic fluid collected by abdominal paracentesis. Each of the whitish colored parasites was less than 1 mm in size. The parasites were morphologically identified as Mesocestoides sp. tetrathyridia. The parasites had four suckers and calcareous corpuscles, but no hooks or rostellum. Mitochondrial (mt) 12S rDNA and mt cytochrome c oxidase subunit 1 DNA amplified from the tetrathyridia were used for molecular identification to species level. DNA sequence analysis showed that the tetrathyridia shared more than 99% identity with M. vogae (syn. M. corti ) for each gene. The patient was treated with a standard dose (5 mg/kg) of praziquantel, which was administered subcutaneously twice at an interval of 14 days. This resulted in successful deworming. This is the first case that CPLC was diagnosed in a dog that had never been taken outside of Japan, indicating that M. vogae is distributed in this country.
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case report first confirmed case of canine peritoneal larval cestodiasis caused by mesocestoides vogae syn m corti in japan
Veterinary Parasitology, 2014Co-Authors: Takuya Kashiide, Yoshiki Yamaya, Aya Uwasawa, Ai Miyoshi, Jun Matsumoto, Toshihiro Watari, Kazuo Yamada, Sadao NogamiAbstract:Abstract Canine peritoneal larval cestodiasis (CPLC) is an unusual parasitic disease in dogs that is caused by asexual proliferation of larval Mesocestoides . A 12 year-old spayed Shetland sheepdog with abdominal distension was referred to the Animal Medical Center at Nihon University, Japan. The presence of ascites was confirmed by abdominal ultrasonography and X-ray imaging. In addition, a number of parasites were observed in the ascitic fluid collected by abdominal paracentesis. Each of the whitish colored parasites was less than 1 mm in size. The parasites were morphologically identified as Mesocestoides sp. tetrathyridia. The parasites had four suckers and calcareous corpuscles, but no hooks or rostellum. Mitochondrial (mt) 12S rDNA and mt cytochrome c oxidase subunit 1 DNA amplified from the tetrathyridia were used for molecular identification to species level. DNA sequence analysis showed that the tetrathyridia shared more than 99% identity with M. vogae (syn. M. corti ) for each gene. The patient was treated with a standard dose (5 mg/kg) of praziquantel, which was administered subcutaneously twice at an interval of 14 days. This resulted in successful deworming. This is the first case that CPLC was diagnosed in a dog that had never been taken outside of Japan, indicating that M. vogae is distributed in this country.
Takuya Kashiide - One of the best experts on this subject based on the ideXlab platform.
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case report first confirmed case of canine peritoneal larval cestodiasis caused by mesocestoides vogae syn m corti in japan
Veterinary Parasitology, 2014Co-Authors: Takuya Kashiide, Yoshiki Yamaya, Aya Uwasawa, Ai Miyoshi, Jun Matsumoto, Toshihiro Watari, Kazuo Yamada, Sadao NogamiAbstract:Abstract Canine peritoneal larval cestodiasis (CPLC) is an unusual parasitic disease in dogs that is caused by asexual proliferation of larval Mesocestoides . A 12 year-old spayed Shetland sheepdog with abdominal distension was referred to the Animal Medical Center at Nihon University, Japan. The presence of ascites was confirmed by abdominal ultrasonography and X-ray imaging. In addition, a number of parasites were observed in the ascitic fluid collected by abdominal paracentesis. Each of the whitish colored parasites was less than 1 mm in size. The parasites were morphologically identified as Mesocestoides sp. tetrathyridia. The parasites had four suckers and calcareous corpuscles, but no hooks or rostellum. Mitochondrial (mt) 12S rDNA and mt cytochrome c oxidase subunit 1 DNA amplified from the tetrathyridia were used for molecular identification to species level. DNA sequence analysis showed that the tetrathyridia shared more than 99% identity with M. vogae (syn. M. corti ) for each gene. The patient was treated with a standard dose (5 mg/kg) of praziquantel, which was administered subcutaneously twice at an interval of 14 days. This resulted in successful deworming. This is the first case that CPLC was diagnosed in a dog that had never been taken outside of Japan, indicating that M. vogae is distributed in this country.
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case report first confirmed case of canine peritoneal larval cestodiasis caused by mesocestoides vogae syn m corti in japan
Veterinary Parasitology, 2014Co-Authors: Takuya Kashiide, Yoshiki Yamaya, Aya Uwasawa, Ai Miyoshi, Jun Matsumoto, Toshihiro Watari, Kazuo Yamada, Sadao NogamiAbstract:Abstract Canine peritoneal larval cestodiasis (CPLC) is an unusual parasitic disease in dogs that is caused by asexual proliferation of larval Mesocestoides . A 12 year-old spayed Shetland sheepdog with abdominal distension was referred to the Animal Medical Center at Nihon University, Japan. The presence of ascites was confirmed by abdominal ultrasonography and X-ray imaging. In addition, a number of parasites were observed in the ascitic fluid collected by abdominal paracentesis. Each of the whitish colored parasites was less than 1 mm in size. The parasites were morphologically identified as Mesocestoides sp. tetrathyridia. The parasites had four suckers and calcareous corpuscles, but no hooks or rostellum. Mitochondrial (mt) 12S rDNA and mt cytochrome c oxidase subunit 1 DNA amplified from the tetrathyridia were used for molecular identification to species level. DNA sequence analysis showed that the tetrathyridia shared more than 99% identity with M. vogae (syn. M. corti ) for each gene. The patient was treated with a standard dose (5 mg/kg) of praziquantel, which was administered subcutaneously twice at an interval of 14 days. This resulted in successful deworming. This is the first case that CPLC was diagnosed in a dog that had never been taken outside of Japan, indicating that M. vogae is distributed in this country.
Walter M Boyce - One of the best experts on this subject based on the ideXlab platform.
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systematics of mesocestoides cestoda mesocestoididae evaluation of molecular and morphological variation among isolates
Journal of Parasitology, 2005Co-Authors: Kerry A Padgett, Steven A Nadler, Linda Munson, Benjamin N Sacks, Walter M BoyceAbstract:A hypothesis-based framework was used to test if 3 genetic strains of Mesocestoides (clades A, B, and C) are distinct evolutionary lineages, thereby supporting their delimitation as species. For comparative purposes, 3 established cestode species, Taenia pisiformis, Taenia serialis, and Taenia crassiceps were assessed using the same methods. Sequence data from mitochondrial rDNA (12S) and the second internal transcribed spacer of nuclear rDNA (ITS-2) revealed derived (autapomorphic) characters for lineages representing clade A (n = 6 autapomorphies), clade B (n = 4), and clade C (n = 9) as well as T. pisiformis (n = 15) and T. serialis (n = 12). Furthermore, multivariate analysis of morphological data revealed significant differences among the 3 genetic strains of Mesocestoides and between T. pisiformis and T. serialis. The level of phenotypic variation within evolutionary lineages of Mesocestoides and Taenia spp. tapeworms was similar. Results from this study support recognizing Mesocestoides clades A, B...
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life history studies on two molecular strains of mesocestoides cestoda mesocestoididae identification of sylvatic hosts and infectivity of immature life stages
Journal of Parasitology, 2004Co-Authors: Kerry A Padgett, Walter M BoyceAbstract:Life-cycle studies were conducted on 2 molecular strains of Mesocestoides tapeworms that represent different evolutionary lineages (clades A and B). Wild carnivores, reptiles, and rodents were examined for tapeworm infections at 2 enzootic sites: (1) San Miguel Island (SMI), a small island off the coast of southern California and (2) Hopland Research and Extension Center (HREC), a field station in northern California. Results indicate that deer mice (Peromyscus maniculatus) and coyotes (Canis latrans) may play an important role in the life cycles of Mesocestoides (clades A and B) in California. Over half the coyotes at HREC and at least a third of the population of island fox (Urocyon littoralis) at SMI were found to harbor clade A adult Mesocestoides spp. One of every 4 Mesocestoides-infected coyotes had tapeworms representing both clades A and B. Experimental inoculations revealed that proglottids (clades A and B) were not directly infectious to rodents, reptiles, or dogs. On the other hand, mice, lizards, and hamsters fed tetrathyridia of Mesocestoides spp. (clades A or B) developed peritoneal tetrathyridial infections. A dog that was fed tetrathyridia (clade B) developed an adult tapeworm infection. Acephalic metacestodes given orally to western fence lizards, laboratory mice, or domestic dogs did not result in metacestode or adult tapeworm infections. Whereas most clade A acephalic metacestodes from dogs were asexually proliferative, clade A tetrathyridia isolated from wild deer mice did not show evidence of asexual replication. Our study supports the hypothesis that a second, as of yet unidentified, intermediate host is necessary to complete the life cycles of Mesocestoides spp., and that acephalic metacestodes represent an aberrant form, incapable of further development.
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life history studies on two molecular strains of mesocestoides cestoda mesocestoididae identification of sylvatic hosts and infectivity of immature life stages
Journal of Parasitology, 2004Co-Authors: Kerry A Padgett, Walter M BoyceAbstract:Life-cycle studies were conducted on 2 molecular strains of Mesocestoides tapeworms that represent different evolutionary lineages (clades A and B). Wild carnivores, reptiles, and rodents were examined for tapeworm infections at 2 enzootic sites: (1) San Miguel Island (SMI), a small island off the coast of southern California and (2) Hopland Research and Extension Center (HREC), a field station in northern California. Results indicate that deer mice (Peromyscus maniculatus) and coyotes (Canis latrans) may play an important role in the life cycles of Mesocestoides (clades A and B) in California. Over half the coyotes at HREC and at least a third of the population of island fox (Urocyon littoralis) at SMI were found to harbor clade A adult Mesocestoides spp. One of every 4 Mesocestoides-infected coyotes had tapeworms representing both clades A and B. Experimental inoculations revealed that proglottids (clades A and B) were not directly infectious to rodents, reptiles, or dogs. On the other hand, mice, lizar...
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molecular systematics of mesocestoides spp cestoda mesocestoididae from domestic dogs canis familiaris and coyotes canis latrans
Journal of Parasitology, 2000Co-Authors: Paul R Crosbie, Edward G. Platzer, Cynthia Kerner, Jean Mariaux, Steven A Nadler, Walter M BoyceAbstract:The genus Mesocestoides Vaillant, 1863 includes tapeworms of uncertain phylogenetic affinities and with poorly defined life histories. We previously documented 11 cases of peritoneal cestodiasis in dogs (Canis familiaris L.) in western North America caused by metacestodes of Mesocestoides spp. In the current study, DNA sequences were obtained from metacestodes collected from these dogs (n = 10), as well as proglottids from dogs (n = 3) and coyotes (Canis latrans Say, 1823 [n = 2]), and tetrathyridia representing laboratory isolates of M. corti (n = 3), and these data were analyzed phylogenetically. Two nuclear genetic markers, 18S ribosomal DNA and the second internal-transcribed spacer (ITS 2), were sequenced. Phylogenetic analysis of the 18S rDNA data recovered a monophyletic group composed of all samples of Mesocestoides spp., distinct from closely related outgroup taxa (Amurotaenia Akhmerov, 1941 and Tetrabothrius Rudolphi, 1819). Initial analysis of the ITS 2 data resolved 3 clades within Mesocestoid...
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MOLECULAR SYSTEMATICS OF MESOCESTOIDES SPP. (CESTODA: MESOCESTOIDIDAE) FROM DOMESTIC DOGS (CANIS FAMILIARIS) AND COYOTES (CANIS LATRANS)
Journal of Parasitology, 2000Co-Authors: Paul R Crosbie, Edward G. Platzer, Cynthia Kerner, Jean Mariaux, Steven A Nadler, Walter M BoyceAbstract:The genus Mesocestoides Vaillant, 1863 includes tapeworms of uncertain phylogenetic affinities and with poorly defined life histories. We previously documented 11 cases of peritoneal cestodiasis in dogs (Canis familiaris L.) in western North America caused by metacestodes of Mesocestoides spp. In the current study, DNA sequences were obtained from metacestodes collected from these dogs (n = 10), as well as proglottids from dogs (n = 3) and coyotes (Canis latrans Say, 1823 [n = 2]), and tetrathyridia representing laboratory isolates of M. corti (n = 3), and these data were analyzed phylogenetically. Two nuclear genetic markers, 18S ribosomal DNA and the second internal-transcribed spacer (ITS 2), were sequenced. Phylogenetic analysis of the 18S rDNA data recovered a monophyletic group composed of all samples of Mesocestoides spp., distinct from closely related outgroup taxa (Amurotaenia Akhmerov, 1941 and Tetrabothrius Rudolphi, 1819). Initial analysis of the ITS 2 data resolved 3 clades within Mesocestoides. Two proglottids from dogs formed a basal clade, a second clade was represented by tetrathyridial isolates, and a third clade included all other samples. Interpretation of these data from an apomorphy-based perspective identified 6 evolutionary lineages. We also assessed whether metacestodes from dogs (n = 4) are capable of asexual proliferation in laboratory mice. One tetrathyridial and 2 acephalic isolates from dogs proliferated asexually. Further investigation is warranted to determine which of the lineages represent distinct species and to determine the life history strategies of Mesocestoides spp.
Laura Dominguez - One of the best experts on this subject based on the ideXlab platform.
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mucin type o glycosylation in mesocestoides vogae syn corti
International Journal for Parasitology, 2008Co-Authors: Andrea Medeiros, Maria Laura Chiribao, Luis Ubillos, Maria Florencia Festari, Jenny Saldana, Carlos Robello, Laura Dominguez, Juan J Calvete, Eduardo OsinagaAbstract:Abstract Protein glycosylation is an important post-translational modification underlying host–parasite interactions, which may determine the outcome of infection. Although Mesocestoides vogae represents an important model for investigating the various aspects of cestode biology, virtually no information is available about the structure and synthesis of glycans in this parasite. In this work, focused on the initiation pathway of mucin-type O -glycosylation in M. vogae , we characterized O -glycoproteins bearing the simple mucin-type cancer-associated Tn and sialyl-Tn antigens, and the expression and activity of ppGalNAc-T, the key enzyme responsible for the first step of mucin-type O -glycosylation. Using immunohistochemistry, Tn and sialyl-Tn antigens were detected mainly in the tegument (microtriches) and in parenchymal cells. Tn expression was also observed in lateral nerve cords. Both Tn and sialyl-Tn antigens were detected in in vitro cultured parasites. Based on their electrophoretic mobility, Tn- and sialyl-Tn-bearing glycoproteins from M. vogae were separated into several components of 22 to 60 kDa. The observation that Tn and sialyl-Tn glycoproteins remained in the 0.6 N perchloric acid-soluble fraction suggested that they could be good candidates for characterizing mucin-type glycosylation in this parasite. O -glycoproteins were purified and initially characterized using a proteomic approach. Immunohistochemical analysis of the tissue distribution of ppGalNAc-T revealed that this enzyme is expressed in the sub-tegumental region and in the parenchyma of the parasite. In M. vogae cultured in vitro, ppGalNAc-T was mainly detected in the suckers. Using a panel of 8 acceptor substrate synthetic peptides, we found that M. vogae ppGalNAc-T preferentially glycosylate threonine residues, the best substrates being peptides derived from human mucin MUC1 and from Trypanosoma cruzi mucin. These results suggest that M. vogae might represent a useful model to study O -glycosylation, and provide new research avenues for future studies on the glycopathobiology of helminth parasites.
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in vitro taurocholate induced segmentation and clustering of mesocestoides vogae syn corti tetrathyridia cestoda inhibition by cestocidal drugs
Parasitology Research, 2001Co-Authors: Jenny Saldana, Monica Marin, Cecilia Fernandez, Laura DominguezAbstract:Mesocestoides vogae (syn. M. corti) tetrathyridia were cultured in the presence of sodium taurocholate, for the purpose of exploring the suitability of this organism for the in vitro assay of cestocidal drugs. Parasite clustering and segmentation were observed as taurocholate-dependent effects in biphasic and monophasic media, respectively. Interestingly, representative members of two major classes of known cestocidal agents (namely, albendazole and praziquantel) blocked these effects. Furthermore, it was possible to determine a specific concentration of the drugs that inhibited clustering and segmentation (minimum inhibitory concentration). In contrast, no inhibition was obtained in the presence of anthelmintics without cestocidal activity. These observations open the way for further studies focused at understanding how the activity of the drugs is involved in the suppression of the taurocholate-induced effects.