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Viatcheslav A Mordvinov - One of the best experts on this subject based on the ideXlab platform.
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inhibition of opisthorchis felineus glutathione dependent prostaglandin synthase by resveratrol correlates with attenuation of cholangiocyte neoplasia in a hamster model of opisthorchiasis
International Journal for Parasitology, 2019Co-Authors: Oxana G Zaparina, Mariya Y Pakharukova, Anna V. Kovner, Viatcheslav A MordvinovAbstract:Abstract Food-borne trematodiases represent major neglected parasitic diseases. Trematodes of the family Opisthorchiidae including Opisthorchis felineus, Opisthorchis viverrini and Clonorchis sinensis are ranked eight on the global list of the 24 most prevalent food-borne parasites. Chronic O. felineus infection symptoms include precancerous lesions with the potential for malignancy. In recent decades, liver flukes of the family Opisthorchiidae have been extensively scientifically explored, however despite this the molecular mechanisms of O. felineus pathogenicity and its carcinogenic potential have not been studied. Opisthorchis felineus glutathione-dependent prostaglandin synthase (GST σ) is the major component of the excretory–secretory product of this liver fluke. We hypothesised that the activity of this enzyme is involved in the infection pathogenesis, including the formation of precancerous lesions. To test this hypothesis and to gain insights into the mechanisms of precancerous lesion formation, we (i) investigated whether excretory parasitic GST σ retains its enzymatic activity, (ii) tested resveratrol (RSV) as a possible inhibitor of this enzyme, and (iii) assessed biliary neoplasia and oxidative DNA damage as well as the expression of neoplasia and fibrogenesis marker genes after prolonged administration of RSV in a hamster model. RSV was found to inhibit GST σ enzymatic activity in a dose-dependent manner (R = 0.85, P
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new insights from opisthorchis felineus genome update on genomics of the epidemiologically important liver flukes
BMC Genomics, 2019Co-Authors: Nikita I. Ershov, Viatcheslav A Mordvinov, Mariya Y Pakharukova, Egor Prokhortchouk, Konstantin V Gunbin, Kirill Ustyantsev, Mikhail A Genaev, Alexander Blinov, A I Mazur, E S BoulyginaAbstract:The three epidemiologically important Opisthorchiidae liver flukes Opisthorchis felineus, O. viverrini, and Clonorchis sinensis, are believed to harbour similar potencies to provoke hepatobiliary diseases in their definitive hosts, although their populations have substantially different ecogeographical aspects including habitat, preferred hosts, population structure. Lack of O. felineus genomic data is an obstacle to the development of comparative molecular biological approaches necessary to obtain new knowledge about the biology of Opisthorchiidae trematodes, to identify essential pathways linked to parasite-host interaction, to predict genes that contribute to liver fluke pathogenesis and for the effective prevention and control of the disease. Here we present the first draft genome assembly of O. felineus and its gene repertoire accompanied by a comparative analysis with that of O. viverrini and Clonorchis sinensis. We observed both noticeably high heterozygosity of the sequenced individual and substantial genetic diversity in a pooled sample. This indicates that potency of O. felineus population for rapid adaptive response to control and preventive measures of opisthorchiasis is higher than in O. viverrini and C. sinensis. We also have found that all three species are characterized by more intensive involvement of trans-splicing in RNA processing compared to other trematodes. All revealed peculiarities of structural organization of genomes are of extreme importance for a proper description of genes and their products in these parasitic species. This should be taken into account both in academic and applied research of epidemiologically important liver flukes. Further comparative genomics studies of liver flukes and non-carcinogenic flatworms allow for generation of well-grounded hypotheses on the mechanisms underlying development of cholangiocarcinoma associated with opisthorchiasis and clonorchiasis as well as species-specific mechanisms of these diseases.
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effect of opisthorchis felineus infection and dimethylnitrosamine administration on the induction of cholangiocarcinoma in syrian hamsters
Parasitology International, 2017Co-Authors: Galina A Maksimova, Banchob Sripa, Mariya Y Pakharukova, E V Kashina, M N Lvova, N. A. Zhukova, Tatyana G. Tolstikova, Anna V. Kovner, Alexey Katokhin, Viatcheslav A MordvinovAbstract:Abstract The food-borne liver trematode Opisthorchis felineus is an emerging source of biliary tract diseases on the territory of the former Soviet Union and Eastern Europe. This parasite along with trematodes Opisthorchis viverrini and Clonorchis sinensis belong to the triad of epidemiologically important liver flukes of the Opisthorchiidae family. It is known that O. viverrini and С. sinensis are the main risk factors of cholangiocarcinoma (CCA) in the endemic regions. The carcinogenic potential of О. felineus has not been well researched because of the absence of systematic pathomorphological, clinical, and epidemiological studies on O. felineus opisthorchiasis. In the present study, we show the results of detailed histopathological analysis and comprehensive evaluation of inflammation, bile duct dysplasia, periductal fibrosis, bile duct hyperplasia, bile duct proliferation, egg granuloma, cysts, cholangiofibrosis, and CCA from 10 to 30 weeks following infection of Syrian hamsters with O. felineus accompanied by oral administration of dimethylnitrosamine (DMN). The results revealed that O. felineus contributes to bile duct cancer development in the hamster model. During the combined action of O. felineus and DMN, morphological features of the liver underwent dramatic changes at the cellular and organ levels. Already in the early stages of the experiment, we observed extensive periductal fibrosis, active inflammation, proliferation of the bile duct, bile duct dysplasia and egg granulomas. Later, against the background of all these changes, cholangiofibrosis and CCA were found. Our work is the first step in the study of carcinogenic potential of O. felineus. Obtained data indicate the risk of CCA of patients having chronic О. felineus opisthorchiasis, and underscore the need for the development of programs for control of this helminthiasis.
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Infection with Opisthorchis felineus induces intraepithelial neoplasia of the biliary tract in a rodent model.
Carcinogenesis, 2017Co-Authors: Maria João Gouveia, Viatcheslav A Mordvinov, Banchob Sripa, Galina A Maksimova, Mariya Y Pakharukova, Thewarach Laha, Gabriel Rinaldi, Teresina Amaro, Lúcio Lara SantosAbstract:The liver fluke Opisthorchis felineus is a member of the triad of epidemiologically relevant species of the trematode family Opisthorchiidae, and the causative agent of opisthorchiasis felinea over an extensive range that spans regions of Eurasia. The International Agency for Research on Cancer classifies the infection with the liver flukes Opisthorchis viverrini and Clonorchis sinensis as group 1 agents and a major risk factor for cholangiocarcinoma. However, the carcinogenic potential of the infection with O. felineus is less clear. Here, we present findings that support the inclusion of O. felineus in the Group 1 list of biological carcinogens. Two discrete lines of evidence support the notion that infection with this liver fluke is carcinogenic. First, novel oxysterol-like metabolites detected by liquid chromatography-mass spectroscopy in the egg and adult developmental stages of O. felineus, and in bile, sera, and urine of liver fluke-infected hamsters exhibited marked similarity to oxysterol-like molecules known from O. viverrini. Numerous oxysterols and related DNA-adducts detected in the liver fluke eggs and in bile from infected hamsters suggested that infection-associated oxysterols induced chromosomal lesions in host cells. Second, histological analysis of liver sections from hamsters infected with O. felineus confirmed portal area enlargement, inflammation with severe periductal fibrosis and changes in the epithelium of the biliary tract characterized as biliary intraepithelial neoplasia, BilIN. The consonance of these biochemical and histopathological changes revealed that O. felineus infection in this rodent model induced precancerous lesions conducive to malignancy.
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experimental opisthorchiasis study of blood cell composition hematopoiesis and startle reflex in laboratory animals
Russian Journal of Genetics: Applied Research, 2017Co-Authors: Damira F. Avgustinovich, E V Kashina, M N Lvova, Alexey V Katokhin, Irina A Orlovskaya, Ludmila B Toporkova, G B Vishnivetskaya, N P Bondar, Natalia A. Feofanova, Viatcheslav A MordvinovAbstract:The Opisthorchis felineus (O. felineus), one of the species from the Opisthorchiidae family, causes severe disorders in the human and animal organism; therefore, it is the subject of topical scientific studies. In this work, a comparative study of the influence of the O. felineus invasions on the change in the blood cell composition, bone marrow hematopoiesis, and behavioral startle reflex was conducted in the C57BL/6 mice and Syrian hamsters two weeks after infection. Significant interspecies differences in many indices were found. It was established that the relative weight of the spleen (the main peripheral immune system organ) is significantly larger in mice than in hamsters. Moreover, the O. felineus invasion caused the hypertrophy of the spleen only in mice. More pronounced deviations from the norm in the blood cell composition, that were accompanied by the activation of myelo- and erythropoiesis, were observed in hamsters. The established changes in the blood in mice were not accompanied by changes in the bone marrow colony-forming activity. Mice also differed from hamsters by the startle reaction to the acoustic signal both by the severity of the reaction and prepulse inhibition value. No habituation reaction to the sound signal was observed in the infected hamsters. In addition, maturation of the O. felineus worms in hamsters occurred earlier than in mice. The data obtained indicate the increased resistance of mice to the O. feluneus infection; however, they do not exclude the possibility of using mice as a model during the study of the processes occurring in the host organism against the background of the experimental opisthorchiasis development.
Daniel Romeroalvarez - One of the best experts on this subject based on the ideXlab platform.
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liver fluke infections by amphimerus sp digenea Opisthorchiidae in definitive and fish intermediate hosts in manabi province ecuador
PLOS Neglected Tropical Diseases, 2020Co-Authors: William Cevallos, Manuel Calvopina, Hideo Kumazawa, Daniel Romeroalvarez, Gabriela Valverdemunoz, Maira Rojas, Hidekazu Takagi, Hiromu SugiyamaAbstract:Amphimerus sp. is a fluke that dwells in the biliary tracts of vertebrate definitive hosts including humans, domestic, and wild mammals in Latin America. Opisthorchiid liver infections are rarely studied in the Americas confirming its status as a neglected tropical disease. In Ecuador, small trematode eggs were reported in human cases from the province of Manabi in 1949, and recently, Amphimerus sp. adults were recovered from human and reservoir hosts in the province of Esmeraldas. Due to the lack of research on the infectious sources of Amphimerus sp. in the continent, we have developed a series of epidemiological studies with parasitological and molecular techniques to elucidate the endemicity of opisthorchiid fluke infections in Manabi, Ecuador. We developed a cross-sectional study in three communities at Pedro Pablo Gomez parish in the province of Manabi, Ecuador. We examined a total of 176 fecal samples to detect opisthorchiid eggs, and four fish species to find opisthorchiid metacercariae. To study adult worms, we treated and purged seven patients in a family and dissected the livers of a dog and a cat infected. We observed morphological features of adults and metacercariae and used polymerase chain reaction with restricted fragment length polymorphism (PCR-RFLP) and DNA sequencing of a section of the ITS2 gene for identification. Small trematode eggs were detected in 63 (35.8%) out of 176 fecal samples of residents in the three study sites. Adult opisthorchiid flukes were recovered from human patients, a dog and a cat, and they were morphologically and molecularly identified as Amphimerus sp. Opisthorchiid metacercariae were also identified molecularly as Amphimerus sp. in four fish species, i.e., Rhoadsia altipinna, Bryconamericus bucay, Andinoacara rivulatus, and Piabucina aureoguttata. Metacercariae of the heterophyid Haplorchis pumilio were also found in the four fish species examined. This is the first study to confirm the current endemicity of Amphimerus sp. in Pedro Pablo Gomez, Manabi, Ecuador. The adult worms isolated here shared morphological characteristics with previous Amphimerus sp. descriptions and were molecularly similar to Amphimerus sp. described in the neighboring province of Esmeraldas. Moreover, this study is the first to document four fish species as infection sources of Amphimerus sp. detected via a molecular protocol targeting the metacercariae of the parasite. Fish species identified here should be targeted for public health campaigns to avoid further human liver-fluke infections by Amphimerus sp. or potential intestinal-fluke infections by H. pumilio or others.
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liver fluke infections by amphimerus sp digenea Opisthorchiidae in definitive and fish intermediate hosts in manabi province ecuador
PLOS Neglected Tropical Diseases, 2020Co-Authors: William Cevallos, Manuel Calvopina, Hideo Kumazawa, Daniel Romeroalvarez, Gabriela Valverdemunoz, Maira Rojas, Hidekazu Takagi, Hiromu SugiyamaAbstract:Amphimerus sp. is a fluke that dwells in the biliary tracts of vertebrate definitive hosts including humans, domestic, and wild mammals in Latin America. Opisthorchiid liver infections are rarely studied in the Americas confirming its status as a neglected tropical disease. In Ecuador, small trematode eggs were reported in human cases from the province of Manabi in 1949, and recently, Amphimerus sp. adults were recovered from human and reservoir hosts in the province of Esmeraldas. Due to the lack of research on the infectious sources of Amphimerus sp. in the continent, we have developed a series of epidemiological studies with parasitological and molecular techniques to elucidate the endemicity of opisthorchiid fluke infections. We developed a cross-sectional study in three communities at Pedro Pablo Gomez parish in the province of Manabi, Ecuador. We examined a total of 176 fecal samples to detect opisthorchiid eggs, and four fish species to find opisthorchiid metacercariae. To study adult worms, we treated and purged seven patients in a family and dissected the livers of a dog and a cat infected. We observed morphological features of adults and metacercariae and used polymerase chain reaction with restricted fragment length polymorphism (PCR-RFLP) and DNA sequencing of a section of the ITS2 gene for identification. Small trematode eggs were detected in 63 (35.8%) out of 176 fecal samples of residents in the three study sites. Adult opisthorchiid flukes were recovered from human patients, a dog and a cat, and they were morphologically and molecularly identified as Amphimerus sp. Opisthorchiid metacercariae were also identified molecularly as Amphimerus sp. in four fish species, i.e., Rhoadsia altipinna, Bryconamericus bucay, Andinoacara rivulatus, and Piabucina aureoguttata. Metacercariae of the heterophyid Haplorchis pumilio were also found in the four fish species examined. This is the first study to confirm the current endemicity of Amphimerus sp. in Pedro Pablo Gomez, Manabi, Ecuador. The adult worms isolated here shared morphological characteristics with previous Amphimerus sp. descriptions and were molecularly similar to Amphimerus sp. described in the province of Esmeraldas. Moreover, this study is the first to document four fish species as infection sources of Amphimerus sp. detected via a molecular protocol targeting the metacercariae of the parasite. Fish species identified here should be targeted for public health campaigns to avoid further human liver-fluke infections by Amphimerus sp. or potential intestinal-fluke infections by H. pumilio or others.
Hiromu Sugiyama - One of the best experts on this subject based on the ideXlab platform.
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liver fluke infections by amphimerus sp digenea Opisthorchiidae in definitive and fish intermediate hosts in manabi province ecuador
PLOS Neglected Tropical Diseases, 2020Co-Authors: William Cevallos, Manuel Calvopina, Hideo Kumazawa, Daniel Romeroalvarez, Gabriela Valverdemunoz, Maira Rojas, Hidekazu Takagi, Hiromu SugiyamaAbstract:Amphimerus sp. is a fluke that dwells in the biliary tracts of vertebrate definitive hosts including humans, domestic, and wild mammals in Latin America. Opisthorchiid liver infections are rarely studied in the Americas confirming its status as a neglected tropical disease. In Ecuador, small trematode eggs were reported in human cases from the province of Manabi in 1949, and recently, Amphimerus sp. adults were recovered from human and reservoir hosts in the province of Esmeraldas. Due to the lack of research on the infectious sources of Amphimerus sp. in the continent, we have developed a series of epidemiological studies with parasitological and molecular techniques to elucidate the endemicity of opisthorchiid fluke infections in Manabi, Ecuador. We developed a cross-sectional study in three communities at Pedro Pablo Gomez parish in the province of Manabi, Ecuador. We examined a total of 176 fecal samples to detect opisthorchiid eggs, and four fish species to find opisthorchiid metacercariae. To study adult worms, we treated and purged seven patients in a family and dissected the livers of a dog and a cat infected. We observed morphological features of adults and metacercariae and used polymerase chain reaction with restricted fragment length polymorphism (PCR-RFLP) and DNA sequencing of a section of the ITS2 gene for identification. Small trematode eggs were detected in 63 (35.8%) out of 176 fecal samples of residents in the three study sites. Adult opisthorchiid flukes were recovered from human patients, a dog and a cat, and they were morphologically and molecularly identified as Amphimerus sp. Opisthorchiid metacercariae were also identified molecularly as Amphimerus sp. in four fish species, i.e., Rhoadsia altipinna, Bryconamericus bucay, Andinoacara rivulatus, and Piabucina aureoguttata. Metacercariae of the heterophyid Haplorchis pumilio were also found in the four fish species examined. This is the first study to confirm the current endemicity of Amphimerus sp. in Pedro Pablo Gomez, Manabi, Ecuador. The adult worms isolated here shared morphological characteristics with previous Amphimerus sp. descriptions and were molecularly similar to Amphimerus sp. described in the neighboring province of Esmeraldas. Moreover, this study is the first to document four fish species as infection sources of Amphimerus sp. detected via a molecular protocol targeting the metacercariae of the parasite. Fish species identified here should be targeted for public health campaigns to avoid further human liver-fluke infections by Amphimerus sp. or potential intestinal-fluke infections by H. pumilio or others.
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liver fluke infections by amphimerus sp digenea Opisthorchiidae in definitive and fish intermediate hosts in manabi province ecuador
PLOS Neglected Tropical Diseases, 2020Co-Authors: William Cevallos, Manuel Calvopina, Hideo Kumazawa, Daniel Romeroalvarez, Gabriela Valverdemunoz, Maira Rojas, Hidekazu Takagi, Hiromu SugiyamaAbstract:Amphimerus sp. is a fluke that dwells in the biliary tracts of vertebrate definitive hosts including humans, domestic, and wild mammals in Latin America. Opisthorchiid liver infections are rarely studied in the Americas confirming its status as a neglected tropical disease. In Ecuador, small trematode eggs were reported in human cases from the province of Manabi in 1949, and recently, Amphimerus sp. adults were recovered from human and reservoir hosts in the province of Esmeraldas. Due to the lack of research on the infectious sources of Amphimerus sp. in the continent, we have developed a series of epidemiological studies with parasitological and molecular techniques to elucidate the endemicity of opisthorchiid fluke infections. We developed a cross-sectional study in three communities at Pedro Pablo Gomez parish in the province of Manabi, Ecuador. We examined a total of 176 fecal samples to detect opisthorchiid eggs, and four fish species to find opisthorchiid metacercariae. To study adult worms, we treated and purged seven patients in a family and dissected the livers of a dog and a cat infected. We observed morphological features of adults and metacercariae and used polymerase chain reaction with restricted fragment length polymorphism (PCR-RFLP) and DNA sequencing of a section of the ITS2 gene for identification. Small trematode eggs were detected in 63 (35.8%) out of 176 fecal samples of residents in the three study sites. Adult opisthorchiid flukes were recovered from human patients, a dog and a cat, and they were morphologically and molecularly identified as Amphimerus sp. Opisthorchiid metacercariae were also identified molecularly as Amphimerus sp. in four fish species, i.e., Rhoadsia altipinna, Bryconamericus bucay, Andinoacara rivulatus, and Piabucina aureoguttata. Metacercariae of the heterophyid Haplorchis pumilio were also found in the four fish species examined. This is the first study to confirm the current endemicity of Amphimerus sp. in Pedro Pablo Gomez, Manabi, Ecuador. The adult worms isolated here shared morphological characteristics with previous Amphimerus sp. descriptions and were molecularly similar to Amphimerus sp. described in the province of Esmeraldas. Moreover, this study is the first to document four fish species as infection sources of Amphimerus sp. detected via a molecular protocol targeting the metacercariae of the parasite. Fish species identified here should be targeted for public health campaigns to avoid further human liver-fluke infections by Amphimerus sp. or potential intestinal-fluke infections by H. pumilio or others.
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characterization of the mitochondrial genome sequences of the liver fluke amphimerus sp trematoda Opisthorchiidae from ecuador and phylogenetic implications
Acta Tropica, 2019Co-Authors: Chengyan Zhou, Miaomiao Sun, William Cevallos, Hiromu Sugiyama, Xingquan Zhu, Manuel CalvopinaAbstract:Abstract Amphimerus Barker, 1911 is a liver fluke infecting several animal species and humans. Being a digenetic trematode of the Opisthorchiidae family, Amphimerus is closely related to the genera Metorchis, Clonorchis and Opisthorchis. Recently, a high prevalence of Amphimerus infection in humans, cats, and dogs had been demonstrated in a tropical Pacific region of Ecuador. Hence, we determined and characterized the entire mt genome sequences of adult liver flukes, morphologically identified as Amphimerus, collected in the endemic region of Ecuador, and examined its phylogenetic relationships with flukes in the Opisthorchiidae family using Bayesian inference (BI) based on the concatenated amino acid sequences and partial cox1 sequences. The complete mt genome sequence (15, 151 bp in length) of the Amphimerus sp. contains 35 genes, including 12 protein-coding genes (PCGs, without atp8), two rRNAs (rrnL and rrnS) and 21 tRNAs, lacking trnG. The gene content and arrangement of the Ecuadorian Amphimerus mt genome was similar to those of other trematodes in the Opisthorchiidae family. All genes in the circular mt genome of Amphimerus sp. are transcribed from the same strand in one direction, with the A + T content of 60.77%. Genetic distances between Amphimerus sp. and other genera in Opisthorchiidae were rather high, ranging from 26.86% to 28.75% at nucleotide level and 29.37%–31.12% at amino acid level. Phylogenetic analysis placed the Ecuadorian Amphimerus within the branch of Opisthorchiidae, but very distinct from Opisthorchis. Our results indicate that the liver fluke Amphimerus from Ecuador does not belong to the genus Opisthorchis, and that it should be assigned under the genus Amphimerus. The determination of the mt genome of the Ecuadorian Amphimerus provides a new genetic resource for future studies on taxonomy and molecular epidemiology of Opisthorchiidae trematodes.
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Adult fluke obtained from the biliary ducts of a cat.
2015Co-Authors: Manuel Calvopina, William Cevallos, Richard Atherton, Matthew Saunders, Alexander Small, Hideo Kumazawa, Hiromu SugiyamaAbstract:The major difference of Amphimerus flukes from the others Opisthorchiidae is that the vitelline glands situated along both lateral sides of the body are divided into anterior and posterior clusters at the level of the ovary, distributed in four groups, 2 anterior and 2 posterior extending nearly to the excretory pore.
Manuel Calvopina - One of the best experts on this subject based on the ideXlab platform.
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liver fluke infections by amphimerus sp digenea Opisthorchiidae in definitive and fish intermediate hosts in manabi province ecuador
PLOS Neglected Tropical Diseases, 2020Co-Authors: William Cevallos, Manuel Calvopina, Hideo Kumazawa, Daniel Romeroalvarez, Gabriela Valverdemunoz, Maira Rojas, Hidekazu Takagi, Hiromu SugiyamaAbstract:Amphimerus sp. is a fluke that dwells in the biliary tracts of vertebrate definitive hosts including humans, domestic, and wild mammals in Latin America. Opisthorchiid liver infections are rarely studied in the Americas confirming its status as a neglected tropical disease. In Ecuador, small trematode eggs were reported in human cases from the province of Manabi in 1949, and recently, Amphimerus sp. adults were recovered from human and reservoir hosts in the province of Esmeraldas. Due to the lack of research on the infectious sources of Amphimerus sp. in the continent, we have developed a series of epidemiological studies with parasitological and molecular techniques to elucidate the endemicity of opisthorchiid fluke infections in Manabi, Ecuador. We developed a cross-sectional study in three communities at Pedro Pablo Gomez parish in the province of Manabi, Ecuador. We examined a total of 176 fecal samples to detect opisthorchiid eggs, and four fish species to find opisthorchiid metacercariae. To study adult worms, we treated and purged seven patients in a family and dissected the livers of a dog and a cat infected. We observed morphological features of adults and metacercariae and used polymerase chain reaction with restricted fragment length polymorphism (PCR-RFLP) and DNA sequencing of a section of the ITS2 gene for identification. Small trematode eggs were detected in 63 (35.8%) out of 176 fecal samples of residents in the three study sites. Adult opisthorchiid flukes were recovered from human patients, a dog and a cat, and they were morphologically and molecularly identified as Amphimerus sp. Opisthorchiid metacercariae were also identified molecularly as Amphimerus sp. in four fish species, i.e., Rhoadsia altipinna, Bryconamericus bucay, Andinoacara rivulatus, and Piabucina aureoguttata. Metacercariae of the heterophyid Haplorchis pumilio were also found in the four fish species examined. This is the first study to confirm the current endemicity of Amphimerus sp. in Pedro Pablo Gomez, Manabi, Ecuador. The adult worms isolated here shared morphological characteristics with previous Amphimerus sp. descriptions and were molecularly similar to Amphimerus sp. described in the neighboring province of Esmeraldas. Moreover, this study is the first to document four fish species as infection sources of Amphimerus sp. detected via a molecular protocol targeting the metacercariae of the parasite. Fish species identified here should be targeted for public health campaigns to avoid further human liver-fluke infections by Amphimerus sp. or potential intestinal-fluke infections by H. pumilio or others.
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liver fluke infections by amphimerus sp digenea Opisthorchiidae in definitive and fish intermediate hosts in manabi province ecuador
PLOS Neglected Tropical Diseases, 2020Co-Authors: William Cevallos, Manuel Calvopina, Hideo Kumazawa, Daniel Romeroalvarez, Gabriela Valverdemunoz, Maira Rojas, Hidekazu Takagi, Hiromu SugiyamaAbstract:Amphimerus sp. is a fluke that dwells in the biliary tracts of vertebrate definitive hosts including humans, domestic, and wild mammals in Latin America. Opisthorchiid liver infections are rarely studied in the Americas confirming its status as a neglected tropical disease. In Ecuador, small trematode eggs were reported in human cases from the province of Manabi in 1949, and recently, Amphimerus sp. adults were recovered from human and reservoir hosts in the province of Esmeraldas. Due to the lack of research on the infectious sources of Amphimerus sp. in the continent, we have developed a series of epidemiological studies with parasitological and molecular techniques to elucidate the endemicity of opisthorchiid fluke infections. We developed a cross-sectional study in three communities at Pedro Pablo Gomez parish in the province of Manabi, Ecuador. We examined a total of 176 fecal samples to detect opisthorchiid eggs, and four fish species to find opisthorchiid metacercariae. To study adult worms, we treated and purged seven patients in a family and dissected the livers of a dog and a cat infected. We observed morphological features of adults and metacercariae and used polymerase chain reaction with restricted fragment length polymorphism (PCR-RFLP) and DNA sequencing of a section of the ITS2 gene for identification. Small trematode eggs were detected in 63 (35.8%) out of 176 fecal samples of residents in the three study sites. Adult opisthorchiid flukes were recovered from human patients, a dog and a cat, and they were morphologically and molecularly identified as Amphimerus sp. Opisthorchiid metacercariae were also identified molecularly as Amphimerus sp. in four fish species, i.e., Rhoadsia altipinna, Bryconamericus bucay, Andinoacara rivulatus, and Piabucina aureoguttata. Metacercariae of the heterophyid Haplorchis pumilio were also found in the four fish species examined. This is the first study to confirm the current endemicity of Amphimerus sp. in Pedro Pablo Gomez, Manabi, Ecuador. The adult worms isolated here shared morphological characteristics with previous Amphimerus sp. descriptions and were molecularly similar to Amphimerus sp. described in the province of Esmeraldas. Moreover, this study is the first to document four fish species as infection sources of Amphimerus sp. detected via a molecular protocol targeting the metacercariae of the parasite. Fish species identified here should be targeted for public health campaigns to avoid further human liver-fluke infections by Amphimerus sp. or potential intestinal-fluke infections by H. pumilio or others.
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characterization of the mitochondrial genome sequences of the liver fluke amphimerus sp trematoda Opisthorchiidae from ecuador and phylogenetic implications
Acta Tropica, 2019Co-Authors: Chengyan Zhou, Miaomiao Sun, William Cevallos, Hiromu Sugiyama, Xingquan Zhu, Manuel CalvopinaAbstract:Abstract Amphimerus Barker, 1911 is a liver fluke infecting several animal species and humans. Being a digenetic trematode of the Opisthorchiidae family, Amphimerus is closely related to the genera Metorchis, Clonorchis and Opisthorchis. Recently, a high prevalence of Amphimerus infection in humans, cats, and dogs had been demonstrated in a tropical Pacific region of Ecuador. Hence, we determined and characterized the entire mt genome sequences of adult liver flukes, morphologically identified as Amphimerus, collected in the endemic region of Ecuador, and examined its phylogenetic relationships with flukes in the Opisthorchiidae family using Bayesian inference (BI) based on the concatenated amino acid sequences and partial cox1 sequences. The complete mt genome sequence (15, 151 bp in length) of the Amphimerus sp. contains 35 genes, including 12 protein-coding genes (PCGs, without atp8), two rRNAs (rrnL and rrnS) and 21 tRNAs, lacking trnG. The gene content and arrangement of the Ecuadorian Amphimerus mt genome was similar to those of other trematodes in the Opisthorchiidae family. All genes in the circular mt genome of Amphimerus sp. are transcribed from the same strand in one direction, with the A + T content of 60.77%. Genetic distances between Amphimerus sp. and other genera in Opisthorchiidae were rather high, ranging from 26.86% to 28.75% at nucleotide level and 29.37%–31.12% at amino acid level. Phylogenetic analysis placed the Ecuadorian Amphimerus within the branch of Opisthorchiidae, but very distinct from Opisthorchis. Our results indicate that the liver fluke Amphimerus from Ecuador does not belong to the genus Opisthorchis, and that it should be assigned under the genus Amphimerus. The determination of the mt genome of the Ecuadorian Amphimerus provides a new genetic resource for future studies on taxonomy and molecular epidemiology of Opisthorchiidae trematodes.
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Adult fluke obtained from the biliary ducts of a cat.
2015Co-Authors: Manuel Calvopina, William Cevallos, Richard Atherton, Matthew Saunders, Alexander Small, Hideo Kumazawa, Hiromu SugiyamaAbstract:The major difference of Amphimerus flukes from the others Opisthorchiidae is that the vitelline glands situated along both lateral sides of the body are divided into anterior and posterior clusters at the level of the ovary, distributed in four groups, 2 anterior and 2 posterior extending nearly to the excretory pore.
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High Prevalence of Human Liver Infection by
2013Co-Authors: Manuel Calvopina, William Cevallos, Hideo Kumazawa, Joseph EisenbergAbstract:Amphimerus spp. flukes are known to infect mammals, but human infections have not been confi rmed. Microscopy of fecal samples from 297 persons from Ecuador revealed Opisthorchiidae eggs in 71 (24%) persons. Light microscopy of adult worms and scanning electron microscopy of eggs were compatible with descriptions of Amphimerus spp. This pathogen was only observed in communities that consumed undercooked fi sh
Sergei V. Shekhovtsov - One of the best experts on this subject based on the ideXlab platform.
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Low Genetic Diversity in Wide-Spread Eurasian Liver Fluke Opisthorchis felineus Suggests Special Demographic History of This Trematode Species
2016Co-Authors: Ilja I. Brusentsov, Alexey Katokhin, Irina V. Brusentsova, Sergei V. Shekhovtsov, Sergei N. Borovikov, Grigoriy G. Goncharenko, Lyudmila A. Lider, Boris V. Romashov, Olga T. Rusinek, Samat K. ShibitovAbstract:Opisthorchis felineus or Siberian liver fluke is a trematode parasite (Opisthorchiidae) that infects the hepato-biliary system of humans and other mammals. Despite its public health significance, this wide-spread Eurasian species is one of the most poorly studied human liver flukes and nothing is known about its population genetic structure and demographic history. In this paper, we attempt to fill this gap for the first time and to explore the genetic diversity in O. felineus populations fro
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Low Genetic Diversity in Wide-Spread Eurasian Liver Fluke Opisthorchis felineus Suggests Special Demographic History of This Trematode Species
PloS one, 2013Co-Authors: Ilja I. Brusentsov, Alexey Katokhin, Irina V. Brusentsova, Sergei V. Shekhovtsov, Sergei N. Borovikov, Grigoriy G. Goncharenko, Lyudmila A. Lider, Boris V. Romashov, Olga T. Rusinek, Samat K. ShibitovAbstract:Opisthorchis felineus or Siberian liver fluke is a trematode parasite (Opisthorchiidae) that infects the hepato-biliary system of humans and other mammals. Despite its public health significance, this wide-spread Eurasian species is one of the most poorly studied human liver flukes and nothing is known about its population genetic structure and demographic history. In this paper, we attempt to fill this gap for the first time and to explore the genetic diversity in O. felineus populations from Eastern Europe (Ukraine, European part of Russia), Northern Asia (Siberia) and Central Asia (Northern Kazakhstan). Analysis of marker DNA fragments from O. felineus mitochondrial cytochrome c oxidase subunit 1 and 3 (cox1, cox3) and nuclear rDNA internal transcribed spacer 1 (ITS1) sequences revealed that genetic diversity is very low across the large geographic range of this species. Microevolutionary processes in populations of trematodes may well be influenced by their peculiar biology. Nevertheless, we suggest that lack of population genetics structure observed in O. felineus can be primarily explained by the Pleistocene glacial events and subsequent sudden population growth from a very limited group of founders. Rapid range expansion of O. felineus through Asian and European territories after severe bottleneck points to a high dispersal potential of this trematode species.
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the complete mitochondrial genomes of the liver flukes opisthorchis felineus and clonorchis sinensis trematoda
Parasitology International, 2010Co-Authors: Sergei V. Shekhovtsov, Alexey V Katokhin, Nikolai A Kolchanov, Viatcheslav A MordvinovAbstract:The complete mitochondrial genomes of the parasitic trematodes Opisthorchis felineus and Clonorchis sinensis (family Opisthorchiidae) were fully sequenced in order to develop markers for DNA diagnostics of the liver flukes infection, molecular ecology, population and phylogenetic studies. The complete sequences of mitochondrial genomes of these species comprise 14,277 and 13,875bp, respectively, and are thus the shortest trematode mitochondrial genomes sequenced to date. The gene content and arrangement are identical to that of Fasciola hepatica. ATG and GTG are used as the start-codons and TAG and TAA are used as the stop-codons. The stop-codon TAG of the C. sinensis nad1 gene overlap by 1nt with the downstream tRNA-Asn gene. Alternative structures for the Ser(UCN) tRNAs were found for both species. The noncoding control regions are separated into two parts by the tRNA-Gly gene and contain neither tandem repeats, which are characteristic for trematode control regions, nor secondary structures. In conclusion, the complete mitochondrial DNA sequences of O. felineus and C. sinensis will serve as a resource for comparative mitochondrial genomics and systematic studies of parasitic trematodes.
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A novel nuclear marker, Pm-int9, for phylogenetic studies of Opisthorchis felineus, Opisthorchis viverrini, and Clonorchis sinensis (Opisthorchiidae, Trematoda)
Parasitology research, 2009Co-Authors: Sergei V. Shekhovtsov, Natalia I Yurlova, Elena а Serbina, Alexey V Katokhin, V.v. Besprozvannykh, Nikolai A Kolchanov, Konstantin V. Romanov, Konstantin P. Fedorov, Viatcheslav A MordvinovAbstract:Opisthorchis felineus, O. viverrini, and Clonorchis sinensis, the trematodes of the family Opisthorchiidae, are important human parasites. Two previous studies (Kang et al. Parasitol Int 57:191-197, 2008; Katokhin et al. Dokl Biochem Biophys 421:214-217, 2008) have provided evidence using ribosomal and mitochondrial sequences that O. viverrini, O. felineus, and C. sinensis are closely related. We developed a novel nuclear marker, Pm-int9, which included the ninth intron of the paramyosin gene and flanking exon sequences. Samples of O. felineus from four localities of West Siberia, C. sinensis from the Russian Far East, and O. viverrini from Thailand were genotyped by Pm-int9. Little variation was detected in exon sequences, however, intron sequences turned out to be more variable than ribosomal internal transcribed spacers. We can conclude that Pm-int9 is valuable for interspecific variation studies. Phylogenetic analysis based on Pm-int9 revealed that O. viverrini and C. sinensis were closer to each other than either of them to O. felineus, supporting the opinion that C. sinensis should be considered the sister species of Opisthorchis spp.