The Experts below are selected from a list of 13260 Experts worldwide ranked by ideXlab platform

Tadashi Itagaki - One of the best experts on this subject based on the ideXlab platform.

  • molecular characterization revealed Fasciola specimens in ecuador are all Fasciola hepatica none at all of Fasciola gigantica or parthenogenic Fasciola species
    Parasitology International, 2021
    Co-Authors: Shinpei Kasahara, Yuma Ohari, Hiromu Sugiyama, Sakura Jin, Manuel Calvopina, Hidekazu Takagi, Tadashi Itagaki
    Abstract:

    Abstract All 225 Fasciola flukes obtained from domestic animals (73 cattle, 7 sheep and 1 pig) of 18 distinct geographic areas in Ecuador-South America, were identified as Fasciola hepatica, based on molecular analyses of nuclear pepck and pold genes, and mitochondrial nad1gene as well as the morphological observation of sperm within the seminal vesicles. Fasciola gigantica and parthenogenic Fasciola forms endemic to Asian countries were not found in this study, although zebu cattle and water buffalos have introduced into South America from Asia; this could be due to the absence of suitable intermediate host snails. The results of pepck analysis using multiplex PCR developed previously showed that 32 of the flukes could not be confirmed as F. hepatica, suggesting that the method is unreliable for the accurate discrimination of F. hepatica, and that pepck gene of the species consists of multiple loci, not a single locus. The results of genetic diversity, phylogenetic, and network analyses based on mitochondrial nad1 sequences suggest that F. hepatica populations in South America, including Ecuador, formed from the ancestral F. hepatica individuals introduced into the continent along with anthropogenic movement of livestock infected with the species.

  • hybrid origin of asian aspermic Fasciola flukes is confirmed by analyzing two single copy genes pepck and pold
    Journal of Veterinary Medical Science, 2017
    Co-Authors: Kei Hayashi, Madoka Ichikawaseki, Tadashi Itagaki, Uday Kumar Mohanta, Takuya Shoriki, Pannigan Chaichanasak
    Abstract:

    Nuclear gene markers, phosphoenolpyruvate carboxykinase (pepck) and DNA polymerase delta (pold), have been developed for precise discrimination of Fasciola flukes instead of internal transcribed spacer 1. In this study, these two genes of 730 Fasciola flukes from eight Asian countries were analyzed. The results were compared with their mitochondrial NADH dehydrogenase subunit 1 (nad1) lineages for obtaining a definitive evidence of the hybrid origin of aspermic Fasciola flukes. All the flukes categorized into the aspermic nad1 lineages possessed both the fragment patterns of F. hepatica and F. gigantica (mixed types) in pepck and/or pold. These findings provide clear evidence for the hybrid origin of aspermic Fasciola lineages and suggest that "aspermic Fasciola flukes" should hereafter be called "hybrid Fasciola flukes".

  • first report of Fasciola larva infection in galba truncatula muller 1774 gastropoda lymnaeidae occurring in the natural environment in hokkaido japan
    Journal of Veterinary Medical Science, 2017
    Co-Authors: Yuma Ohari, Kei Hayashi, Tadashi Itagaki, Uday Kumar Mohanta, Yasuhiro Kuwahara
    Abstract:

    In Hokkaido, Japan, wild sika deer are highly infected with Fasciola flukes, suggesting that the flukes complete their life cycle via intermediate host snails and definitive host animals occurring in the natural environment. However, infected snails have been found only in cattle farms contaminated with fasciolosis. This study reports the first Fasciola larva infection in Galba truncatula snails occurring in the Shoro and Atsuma rivers in the natural environment. Molecular analysis revealed that the nad1 haplotype of the larvae was consistent with that of Fasciola adults obtained from sika deer in Hokkaido. These results indicated that Fasciola flukes complete their life cycle via G. truncatula and sika deer occurring in the natural environment.

  • nuclear and mitochondrial dna analysis reveals that hybridization between Fasciola hepatica and Fasciola gigantica occurred in china
    Parasitology, 2017
    Co-Authors: Mao Peng, Toshiyuki Shibahara, Uday Kumar Mohanta, Takuya Shoriki, Tadashi Itagaki
    Abstract:

    The well-known pathogens of fasciolosis, Fasciola hepatica (Fh) and Fasciola Gigantica (Fg), possess abundant mature sperms in their seminal vesicles, and thus, they reproduce bisexually. On the other hand, aspermic Fasciola flukes reported from Asian countries, which have no sperm in their seminal vesicles, probably reproduce parthenogenetically. The aim of this study was to reveal the origin of aspermic Fasciola flukes. The nuclear single copy markers, phosphoenolpyruvate carboxykinase and DNA polymerase delta, were employed for analysis of Fasciola species from China. The hybrid origin of aspermic Fasciola flukes was strongly suggested by the presence of the Fh/Fg type, which includes DNA fragments of both F. hepatica and F. gigantica. China can be regarded as the cradle of the interspecific hybridization because F. hepatica and F. gigantica were detected in the northern and southern parts of China, respectively, and hybrids flukes were distributed between the habitats of the two species. The Chinese origin was supported by the fact that a larger number of mitochondrial NADH dehydrogenase subunit 1 (nad1) haplotypes was detected in Chinese aspermic Fasciola populations than in aspermic populations from the neighbouring countries. Hereafter, 'aspermic' Fasciola flukes should be termed as 'hybrid' Fasciola flukes.

  • molecular phylogenetic analysis of Fasciola flukes from eastern india
    Parasitology International, 2015
    Co-Authors: Kei Hayashi, Madoka Ichikawaseki, Uday Kumar Mohanta, Takuya Shoriki, Shantikumar T Singh, Hiromu Sugiyama, Tadashi Itagaki
    Abstract:

    Fasciola flukes from eastern India were characterized on the basis of spermatogenesis status and nuclear ITS1. Both Fasciola gigantica and aspermic Fasciola flukes were detected in Imphal, Kohima, and Gantoku districts. The sequences of mitochondrial nad1 were analyzed to infer their phylogenetical relationship with neighboring countries. The haplotypes of aspermic Fasciola flukes were identical or showed a single nucleotide substitution compared to those from populations in the neighboring countries, corroborating the previous reports that categorized them in the same lineage. However, the prevalence of aspermic Fasciola flukes in eastern India was lower than those in the neighboring countries, suggesting that they have not dispersed throughout eastern India. In contrast, F. gigantica was predominant and well diversified, and the species was thought to be distributed in the area for a longer time than the aspermic Fasciola flukes. Fasciola gigantica populations from eastern India were categorized into two distinct haplogroups A and B. The level of their genetic diversity suggests that populations belonging to haplogroup A have dispersed from the west side of the Indian subcontinent to eastern India with the artificial movement of domestic cattle, Bos indicus, whereas populations belonging to haplogroup B might have spread from Myanmar to eastern India with domestic buffaloes, Bubalus bubalis.

X Q Zhu - One of the best experts on this subject based on the ideXlab platform.

  • rapid identification and differentiation of Fasciola hepatica and Fasciola gigantica by a loop mediated isothermal amplification lamp assay
    Veterinary Parasitology, 2010
    Co-Authors: Hany M. Elsheikha, X Q Zhu, Sungjong Hong, J X Chen, S H Chen, X Q Cai, M X Chen
    Abstract:

    Abstract The present study developed and validated a species-specific loop-mediated isothermal amplification (LAMP) assay for the rapid detection and discrimination of Fasciola hepatica and Fasciola gigantica. The LAMP assay is inexpensive, easy to perform and shows rapid reaction, wherein the amplification can be obtained in 45 min under isothermal conditions of 61 °C or 62 °C by employing a set of four species-specific primer mixtures and results can be checked through naked-eye visualization. The optimal assay conditions with no cross-reaction with other closely related trematodes (Clonorchis sinensis, Opisthorchis viverrini, Orientobilharzia turkestanicum and Schistosoma japonicum) as well as within the two Fasciola species were established. The assay was validated by examining F. gigantica DNA in the intermediate host snails and in faecal samples. The results indicated that the LAMP assay is approximately 104 times more sensitive than the conventional specific PCR assays. These findings indicate that this Fasciola species-specific LAMP assay may have a potential clinical application for detection and differentiation of Fasciola species, especially in endemic countries.

  • genetic characterisation of Fasciola samples from different host species and geographical localities revealed the existence of f hepatica and f gigantica in niger
    Parasitology Research, 2008
    Co-Authors: Hina Ali, Huiqun Song, S Ali, R Q Lin, B Seyni, G Issa, X Q Zhu
    Abstract:

    In the present study, 16 samples representing Fasciola (Platyhelminthes: Trematoda: Digenea) from sheep and cattle from seven geographical locations in Niger were characterized genetically by sequences of the first (ITS-1) and second (ITS-2) internal transcribed spacers (ITS) of nuclear ribosomal DNA (rDNA). The ITS rDNA was amplified from individual liver flukes by polymerase chain reaction (PCR), and the amplicons were sequenced directly. The lengths of the ITS-1 and ITS-2 sequences were 422 and 361/362 bp, respectively, for all liver fluke samples sequenced. Comparison of the ITS sequences of the Niger Fasciola samples examined in the present study with that of Fasciola hepatica, Fasciola gigantica, and the "intermediate Fasciola" from elsewhere revealed that the Niger Fasciola samples examined represent two species, namely F. hepatica and F. gigantica. This is the first demonstration of the existence of both F. hepatica and F. gigantica in Niger by a genetic approach, which provides foundation for further studies on F. hepatica and F. gigantica in Niger and has implications for studying the population genetic structure of the Niger Fasciola and for the diagnosis and control of the disease they cause.

  • characterization of Fasciola samples from different host species and geographical localities in spain by sequences of internal transcribed spacers of rdna
    Parasitology Research, 2007
    Co-Authors: Samer Alasaad, C Q Huang, Jose E Granados, C Garciaromero, J M Perez, X Q Zhu
    Abstract:

    In the present study, 25 samples representing Fasciola (Platyhelminthes: Trematoda: Digenea) from nine host species and 19 geographical locations in Spain were characterized genetically by sequences of the first (ITS-1) and second (ITS-2) internal transcribed spacers (ITS) of nuclear ribosomal DNA (rDNA). The ITS rDNA was amplified from individual liver flukes by polymerase chain reaction (PCR), and the amplicons were sequenced directly. The lengths of the ITS-1 and ITS-2 sequences were 422 and 362 bp, respectively, for all Spanish liver fluke samples sequenced. Comparison of the ITS sequences of the Spanish Fasciola samples examined in the present study with that of Fasciola hepatica, Fasciola gigantica and the "intermediate Fasciola" revealed that all Spanish Fasciola samples examined represent the single species of F. hepatica, with only slight sequence variation in the ITS-2 (1/362, 0.3%) among the sequenced samples, but the sequence variation was not related to particular host species and/or geographical origins of the samples. The Spanish F. hepatica examined differed from Fasciola from elsewhere by two nucleotides in the ITS-2, which provided genetic marker for the differentiation of Spanish F. hepatica from Fasciola from other geographical localities. These results have implications for studying the population genetic structure of the Spanish F. hepatica and for the diagnosis and control of the disease it causes.

  • characterisation of Fasciola species from mainland china by its 2 ribosomal dna sequence
    Veterinary Parasitology, 2004
    Co-Authors: Weiyi Huang, C R Wang, X Q Zhu
    Abstract:

    Abstract Isolates of Fasciola (Platyhelminthes: Trematoda: Digenea) from different host species and geographical locations in Mainland China were characterised genetically. The second internal transcribed spacer (ITS-2) of nuclear ribosomal DNA (rDNA) was amplified from individual trematodes by polymerase chain reaction (PCR), and the representative amplicons were cloned and sequenced. The length of the ITS-2 sequences was 361–362 bp for all Chinese Fasciola specimens sequenced. While there was no variation in length or composition of the ITS-2 sequences among multiple specimens from France, Sichuan and Guangxi, sequence difference of 1.7% (6/362) was detected between specimens from France and Sichuan, and those from Guangxi. Based on ITS-2 sequence data, it was concluded that the Fasciola from Sichuan represented Fasciola hepatica , the one from Guangxi represented Fasciola gigantica and the one from sheep from Heilongjiang may represent an “intermediate genotype”, as its ITS-2 sequences were unique in that two different ITS-2 sequences exist in the rDNA array within a single Fasciola worm. One of the sequences is identical to that of F. hepatica , and the other is almost identical to that of F. gigantica in that nucleotides at five of the six polymorphic positions represent F. gigantica . This microheterogeneity is possibly due to sequence polymorphism among copies of the ITS-2 array within the same worm. Based on the sequence differences, a PCR-linked restriction fragment length polymorphism (PCR-RFLP) assay was established for the unequivocal delineation of the Fasciola spp. from Mainland China using restriction endonuclease Hsp 92II or Rca I. This assay should provide a valuable tool for the molecular identification and for studying the ecology and population genetic structures of Fasciola spp. from Mainland China and elsewhere.

Xingquan Zhu - One of the best experts on this subject based on the ideXlab platform.

  • complete mitochondrial genomes of the intermediate form of Fasciola and Fasciola gigantica and their comparison with f hepatica
    Parasites & Vectors, 2014
    Co-Authors: Guohua Liu, Robin B. Gasser, Neil D Young, Huiqun Song, Xingquan Zhu
    Abstract:

    Background Fascioliasis is an important and neglected disease of humans and other mammals, caused by trematodes of the genus Fasciola. Fasciola hepatica and F. gigantica are valid species that infect humans and animals, but the specific status of Fasciola sp. (‘intermediate form’) is unclear.

  • complete mitochondrial genomes of the intermediate form of Fasciola and Fasciola gigantica and their comparison with f hepatica
    Parasites & Vectors, 2014
    Co-Authors: Guohua Liu, Robin B. Gasser, Neil D Young, Huiqun Song, Xingquan Zhu
    Abstract:

    Fascioliasis is an important and neglected disease of humans and other mammals, caused by trematodes of the genus Fasciola. Fasciola hepatica and F. gigantica are valid species that infect humans and animals, but the specific status of Fasciola sp. (‘intermediate form’) is unclear. Single specimens inferred to represent Fasciola sp. (‘intermediate form’; Heilongjiang) and F. gigantica (Guangxi) from China were genetically identified and characterized using PCR-based sequencing of the first and second internal transcribed spacer regions of nuclear ribosomal DNA. The complete mitochondrial (mt) genomes of these representative specimens were then sequenced. The relationships of these specimens with selected members of the Trematoda were assessed by phylogenetic analysis of concatenated amino acid sequence datasets by Bayesian inference (BI). The complete mt genomes of representatives of Fasciola sp. and F. gigantica were 14,453 bp and 14,478 bp in size, respectively. Both mt genomes contain 12 protein-coding genes, 22 transfer RNA genes and two ribosomal RNA genes, but lack an atp 8 gene. All protein-coding genes are transcribed in the same direction, and the gene order in both mt genomes is the same as that published for F. hepatica. Phylogenetic analysis of the concatenated amino acid sequence data for all 12 protein-coding genes showed that the specimen of Fasciola sp. was more closely related to F. gigantica than to F. hepatica. The mt genomes characterized here provide a rich source of markers, which can be used in combination with nuclear markers and imaging techniques, for future comparative studies of the biology of Fasciola sp. from China and other countries.

  • genetic characterization species differentiation and detection of Fasciola spp by molecular approaches
    Parasites & Vectors, 2011
    Co-Authors: Hany M. Elsheikha, Samer Alasaad, Xingquan Zhu, Muxin Chen, Ruiqing Lin, Fengcai Zou, Jiaxu Chen
    Abstract:

    Liver flukes belonging to the genus Fasciola are among the causes of foodborne diseases of parasitic etiology. These parasites cause significant public health problems and substantial economic losses to the livestock industry. Therefore, it is important to definitively characterize the Fasciola species. Current phenotypic techniques fail to reflect the full extent of the diversity of Fasciola spp. In this respect, the use of molecular techniques to identify and differentiate Fasciola spp. offer considerable advantages. The advent of a variety of molecular genetic techniques also provides a powerful method to elucidate many aspects of Fasciola biology, epidemiology, and genetics. However, the discriminatory power of these molecular methods varies, as does the speed and ease of performance and cost. There is a need for the development of new methods to identify the mechanisms underpinning the origin and maintenance of genetic variation within and among Fasciola populations. The increasing application of the current and new methods will yield a much improved understanding of Fasciola epidemiology and evolution as well as more effective means of parasite control. Herein, we provide an overview of the molecular techniques that are being used for the genetic characterization, detection and genotyping of Fasciola spp..

David Blair - One of the best experts on this subject based on the ideXlab platform.

  • adaptive radiation of the flukes of the family fasciolidae inferred from genome wide comparisons of key species
    Molecular Biology and Evolution, 2020
    Co-Authors: Young Jun Choi, Santiago Fontenla, David Blair, Peter U Fischer, Alicia Costabile, Paul J Brindley, Jose F Tort, Miguel M Cabada, Makedonka Mitreva
    Abstract:

    Liver and intestinal flukes of the family Fasciolidae cause zoonotic food-borne infections that impact both agriculture and human health throughout the world. Their evolutionary history and the genetic basis underlying their phenotypic and ecological diversity are not well understood. To close that knowledge gap, we compared the whole genomes of Fasciola hepatica, Fasciola gigantica, and Fasciolopsis buski and determined that the split between Fasciolopsis and Fasciola took place similar to 90 Ma in the late Cretaceous period, and that between 65 and 50 Ma an intermediate host switch and a shift from intestinal to hepatic habitats occurred in the Fasciola lineage. The rapid climatic and ecological changes occurring during this period may have contributed to the adaptive radiation of these flukes. Expansion of cathepsins, fatty-acid-binding proteins, protein disulfide-isomerases, and molecular chaperones in the genus Fasciola highlights the significance of excretory-secretory proteins in these liver-dwelling flukes. Fasciola hepatica and Fasciola gigantica diverged similar to 5 Ma near the Miocene-Pliocene boundary that coincides with reduced faunal exchange between Africa and Eurasia. Severe decrease in the effective population size similar to 10ka in Fasciola is consistent with a founder effect associated with its recent global spread through ruminant domestication. G-protein-coupled receptors may have key roles in adaptation of physiology and behavior to new ecological niches. This study has provided novel insights about the genome evolution of these important pathogens, has generated genomic resources to enable development of improved interventions and diagnosis, and has laid a solid foundation for genomic epidemiology to trace drug resistance and to aid surveillance.

  • human fascioliasis and the presence of hybrid introgressed forms of Fasciola hepatica and Fasciola gigantica in vietnam
    International Journal for Parasitology, 2008
    Co-Authors: Nguyen Van De, Thanh Giang Thi Nguyen, Takeshi Agatsuma, Donald P Mcmanus, Quoc Doanh Nguyen, David Blair
    Abstract:

    The two species common of liver fluke, Fasciola hepatica and Fasciola gigantica, cause human fascioliasis. Hybrids between these species, and introgressed forms of Fasciola, are known from temperate and subtropical regions of eastern Asia. Here, we report the presence of hybrid and/or introgressed liver flukes in Vietnam where it has recently been recognised that human fascioliasis is an important zoonotic disease. Specimens examined came from domestic stock (cattle and buffalo) at slaughter and also from human patients. DNA sequences were obtained from the nuclear ribosomal second internal transcribed spacer (ITS-2) and from portions of two mitochondrial protein-coding genes. Mitochondrial sequences in every case were similar to those of Fasciola gigantica. Nuclear ITS-2 sequences belonged to one or other of the Fasciola species, or, sequences from both were found in the same individual worm. This study extends the known range of hybrids or introgressed forms of Fasciola into tropical regions of Asia.

  • mitochondrial dna and nuclear dna indicate that the japanese Fasciola species is f gigantica
    Parasitology Research, 1997
    Co-Authors: Koichi Hashimoto, David Blair, T Watanobe, C X Liu, I Init, S Ohnishi, Takeshi Agatsuma
    Abstract:

    For elucidation of the taxonomic status of the Japanese Fasciola species, whole mitochondrial DNA of Fasciola hepatica from Australia, F. gigantica from Malaysia, and Fasciola sp. from Japan was digested with three four-base-cutting endonucleases: HinfI, MspI, and RsaI. The resulting digestion patterns showed that for each enzyme there were some bands specific for each geographical isolate and that the Japanese Fasciola sp. shared more bands with F. gigantica than with F. hepatica. Nucleotide sequences of two regions, the second internal transcribed spacer (ITS2) of the nuclear ribosomal RNA cluster and mitochondrial cytochrome c oxidase subunit I (COI), were also compared among them. The ITS2 sequence was highly conserved among the three isolates. F. gigantica and the Japanese Fasciola sp. were identical, but they differed from the Australian F. hepatica at six sites, one of which was a deletion. The COI sequence was less conserved but implied a similar relationship between the isolates. There seems no reason to regard the Japanese Fasciola sp. as anything other than a strain of F. gigantica.

  • comparison of the second internal transcribed spacer ribosomal dna from populations and species of fasciolidae digenea
    International Journal for Parasitology, 1993
    Co-Authors: R D Adlard, Stephen C Barker, David Blair, Thomas H Cribb
    Abstract:

    The nucleotide sequence of the 3' end of the second internal transcribed spacer region (ITS2) was determined for four isolates of Fasciola hepatica, two isolates of Fasciola gigantica, one isolate of Fascioloides magna and one isolate of Fasciola sp. from Japan. Intraspecific sequence divergence was negligible. Sequence divergence between F. hepatica and F. gigantica was 2.8% and between Fasciola hepatica and Fascioloides magna was 13.2%. The sequence of Fasciola sp. from Japan matched closely that of F. gigantica. This study demonstrates variability in nucleotide sequence within the ITS2 region which allows discrimination between species of Fasciolidae.

Mao Peng - One of the best experts on this subject based on the ideXlab platform.

  • nuclear and mitochondrial dna analysis reveals that hybridization between Fasciola hepatica and Fasciola gigantica occurred in china
    Parasitology, 2017
    Co-Authors: Mao Peng, Toshiyuki Shibahara, Uday Kumar Mohanta, Takuya Shoriki, Tadashi Itagaki
    Abstract:

    The well-known pathogens of fasciolosis, Fasciola hepatica (Fh) and Fasciola Gigantica (Fg), possess abundant mature sperms in their seminal vesicles, and thus, they reproduce bisexually. On the other hand, aspermic Fasciola flukes reported from Asian countries, which have no sperm in their seminal vesicles, probably reproduce parthenogenetically. The aim of this study was to reveal the origin of aspermic Fasciola flukes. The nuclear single copy markers, phosphoenolpyruvate carboxykinase and DNA polymerase delta, were employed for analysis of Fasciola species from China. The hybrid origin of aspermic Fasciola flukes was strongly suggested by the presence of the Fh/Fg type, which includes DNA fragments of both F. hepatica and F. gigantica. China can be regarded as the cradle of the interspecific hybridization because F. hepatica and F. gigantica were detected in the northern and southern parts of China, respectively, and hybrids flukes were distributed between the habitats of the two species. The Chinese origin was supported by the fact that a larger number of mitochondrial NADH dehydrogenase subunit 1 (nad1) haplotypes was detected in Chinese aspermic Fasciola populations than in aspermic populations from the neighbouring countries. Hereafter, 'aspermic' Fasciola flukes should be termed as 'hybrid' Fasciola flukes.

  • molecular characterization of Fasciola hepatica Fasciola gigantica and aspermic Fasciola sp in china based on nuclear and mitochondrial dna
    Parasitology Research, 2009
    Co-Authors: Toshiyuki Shibahara, M Ichinomiya, Mao Peng, Maiko Ohtori, Madoka Ichikawa, Tadashi Itagaki
    Abstract:

    Parthenogenic Fasciola forms as well as bisexual Fasciola hepatica and Fasciola gigantica in mainland China have been identified on the basis of their spermatogenesis and genotypes in nuclear ribosomal internal transcribed spacer 1 (ITS1) and mitochondrial NADH dehydrogenase I (NDI). The Chinese aspermic Fasciola would include forms originating in interspecific hybrids between F. hepatica and F. gigantica, since they showed the genotype of ITS1-Fh/Fg that had mixed sequences of the two Fasciola species or heterogeneous genotypes in ITS1 and NDI. Additionally, there were Chinese aspermic flukes in which the sequences of ITS1 and NDI genotypes completely coincided with those in aspermic forms from Japan, Korea, and Vietnam, suggesting that the aspermic forms from these four countries are offspring with a common provenance. The Fh-C4 haplotype in NDI was detected in both aspermic specimens and F. hepatica, indicating that aspermic forms showing the haplotype might come into existence in China. The ratio of body length and width in aspermic Fasciola specimens showed intermediate values between those of F. hepatica and F. gigantica.