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Sample records for blood fluke exploitation

  1. Blood Fluke Exploitation of Innate-Adaptive Immune Interactions to Facilitate Parasite Development

    DTIC Science & Technology

    2007-01-01

    Risk \\j 7 Schistosome Life Cycle Schistosoma are digenean blood flukes, whose life cycle alternates between an asexual reproductive phase...in molluscan intermediate hosts and a sexual reproductive phase in vertebrate definitive hosts. Maintenance of the schistosome life cycle is...Following infection, the miracidium transforms into a primary sporocyst and two generations of asexual amplification occur, ending with the production

  2. The genome of a blood fluke associated with human cancer

    PubMed Central

    Mitreva, Makedonka

    2013-01-01

    The sequencing of the genome and transcriptome of Schistosoma haematobium, a highly prevalent blood fluke and human parasite with a proven link to malignant bladder cancer, marks the 160th anniversary of its discovery as the first schistosome known to infect humans. Comparative genomic analyses of S. haematobium and the more prevalent human-schistosomiasis pathogens (Schistosoma mansoni and Schistosoma japonicum) identified both shared and distinct genomic features. PMID:22281765

  3. The genome of the blood fluke Schistosoma mansoni.

    PubMed

    Berriman, Matthew; Haas, Brian J; LoVerde, Philip T; Wilson, R Alan; Dillon, Gary P; Cerqueira, Gustavo C; Mashiyama, Susan T; Al-Lazikani, Bissan; Andrade, Luiza F; Ashton, Peter D; Aslett, Martin A; Bartholomeu, Daniella C; Blandin, Gaelle; Caffrey, Conor R; Coghlan, Avril; Coulson, Richard; Day, Tim A; Delcher, Art; DeMarco, Ricardo; Djikeng, Appolinaire; Eyre, Tina; Gamble, John A; Ghedin, Elodie; Gu, Yong; Hertz-Fowler, Christiane; Hirai, Hirohisha; Hirai, Yuriko; Houston, Robin; Ivens, Alasdair; Johnston, David A; Lacerda, Daniela; Macedo, Camila D; McVeigh, Paul; Ning, Zemin; Oliveira, Guilherme; Overington, John P; Parkhill, Julian; Pertea, Mihaela; Pierce, Raymond J; Protasio, Anna V; Quail, Michael A; Rajandream, Marie-Adèle; Rogers, Jane; Sajid, Mohammed; Salzberg, Steven L; Stanke, Mario; Tivey, Adrian R; White, Owen; Williams, David L; Wortman, Jennifer; Wu, Wenjie; Zamanian, Mostafa; Zerlotini, Adhemar; Fraser-Liggett, Claire M; Barrell, Barclay G; El-Sayed, Najib M

    2009-07-16

    Schistosoma mansoni is responsible for the neglected tropical disease schistosomiasis that affects 210 million people in 76 countries. Here we present analysis of the 363 megabase nuclear genome of the blood fluke. It encodes at least 11,809 genes, with an unusual intron size distribution, and new families of micro-exon genes that undergo frequent alternative splicing. As the first sequenced flatworm, and a representative of the Lophotrochozoa, it offers insights into early events in the evolution of the animals, including the development of a body pattern with bilateral symmetry, and the development of tissues into organs. Our analysis has been informed by the need to find new drug targets. The deficits in lipid metabolism that make schistosomes dependent on the host are revealed, and the identification of membrane receptors, ion channels and more than 300 proteases provide new insights into the biology of the life cycle and new targets. Bioinformatics approaches have identified metabolic chokepoints, and a chemogenomic screen has pinpointed schistosome proteins for which existing drugs may be active. The information generated provides an invaluable resource for the research community to develop much needed new control tools for the treatment and eradication of this important and neglected disease.

  4. Genomic linkage map of the human blood fluke Schistosoma mansoni

    PubMed Central

    Criscione, Charles D; Valentim, Claudia LL; Hirai, Hirohisa; LoVerde, Philip T; Anderson, Timothy JC

    2009-01-01

    Background Schistosoma mansoni is a blood fluke that infects approximately 90 million people. The complete life cycle of this parasite can be maintained in the laboratory, making this one of the few experimentally tractable human helminth infections, and a rich literature reveals heritable variation in important biomedical traits such as virulence, host-specificity, transmission and drug resistance. However, there is a current lack of tools needed to study S. mansoni's molecular, quantitative, and population genetics. Our goal was to construct a genetic linkage map for S. mansoni, and thus provide a new resource that will help stimulate research on this neglected pathogen. Results We genotyped grandparents, parents and 88 progeny to construct a 5.6 cM linkage map containing 243 microsatellites positioned on 203 of the largest scaffolds in the genome sequence. The map allows 70% of the estimated 300 Mb genome to be ordered on chromosomes, and highlights where scaffolds have been incorrectly assembled. The markers fall into eight main linkage groups, consistent with seven pairs of autosomes and one pair of sex chromosomes, and we were able to anchor linkage groups to chromosomes using fluorescent in situ hybridization. The genome measures 1,228.6 cM. Marker segregation reveals higher female recombination, confirms ZW inheritance patterns, and identifies recombination hotspots and regions of segregation distortion. Conclusions The genetic linkage map presented here is the first for S. mansoni and the first for a species in the phylum Platyhelminthes. The map provides the critical tool necessary for quantitative genetic analysis, aids genome assembly, and furnishes a framework for comparative flatworm genomics and field-based molecular epidemiological studies. PMID:19566921

  5. Two New Genera of Fish Blood Flukes (Digenea: Aporocotylidae) from Catfishes in the Peruvian Amazon.

    PubMed

    Orélis-Ribeiro, Raphael; Bullard, Stephen A

    2016-06-01

    Cladocaecum tomasscholzi n. gen., n. sp. infects the heart (lumen of ventricle) of driftwood catfish, Ageneiosus inermis Linnaeus, 1766 (Siluriformes: Auchenipteridae) from the Nanay River (Amazon River Basin, near Iquitos, Peru). It differs from all other aporocotylid genera by having a highly branched intestine comprising a central cecum that terminates immediately anterior to the ovary and that has numerous laterally directed diverticula. Kritsky platyrhynchi ( Guidelli, Isaac, and Pavanelli, 2002 ) n. gen., n. comb. (= Plehniella p.) is redescribed based on paratypes plus new specimens collected from the body cavity of the type host (porthole shovelnose catfish, Hemisorubim platyrhynchos Valenciennes, 1840) (Pimelodidae) from the nearby Itaya River. Kritsky differs from Sanguinicola Plehn, 1905 , Plehniella Szidat, 1951 , Nomasanguinicola Truong and Bullard, 2013 , and Cladocaecum by the combination of having a spinous anterior sucker, an intestine comprising 6 asymmetrical ceca, a lanceolate body, a straight vas deferens, an ovary with finger-like lateral projections, a small and spheroid oötype, numerous, minute, spheroid uterine eggs, and separate genital pores. An updated list of hosts, tissues infected, and geographic localities for the catfish blood flukes (9 spp.; 5 genera) is provided. This is the first report of a fish blood fluke infecting a member of Auchenipteridae and first proposal of a new genus of blood fluke (Schistosomatoidea) from South America in 64 yr. It brings the total number of Amazonian fish blood flukes to a mere 4 species.

  6. New Genus of Blood Fluke (Digenea: Schistosomatoidea) from Malaysian Freshwater Turtles (Geoemydidae) and its Phylogenetic Position Within Schistosomatoidea.

    PubMed

    Roberts, Jackson R; Platt, Thomas R; Orélis-Ribeiro, Raphael; Bullard, Stephen A

    2016-08-01

    :  Baracktrema obamai n. gen., n. sp. infects the lung of geoemydid turtles (black marsh turtle, Siebenrockiella crassicollis [type host] and southeast Asian box turtle, Cuora amboinensis ) in the Malaysian states of Perak, Perlis, and Selangor. Baracktrema and Unicaecum Stunkard, 1925 are the only accepted turtle blood fluke genera having the combination of a single cecum, single testis, oviducal seminal receptacle, and uterine pouch. Baracktrema differs from Unicaecum by having a thread-like body approximately 30-50× longer than wide and post-cecal terminal genitalia. Unicaecum has a body approximately 8-12× longer than wide and terminal genitalia that are anterior to the distal end of the cecum. The new genus further differs from all other accepted turtle blood fluke genera by having a cecum that is highly convoluted for its entire length, a spindle-shaped ovary between the cirrus sac and testis, a uterine pouch that loops around the primary vitelline collecting duct, a Laurer's canal, and a dorsal common genital pore. Phylogenetic analysis of the D1-D3 domains of the nuclear large subunit ribosomal DNA (28S) revealed, with high nodal support and as predicted by morphology, that Baracktrema and Unicaecum share a recent common ancestor and form a clade sister to the freshwater turtle blood flukes of Spirorchis, paraphyletic Spirhapalum, and Vasotrema and that, collectively, these flukes were sister to all other tetrapod blood flukes (Hapalorhynchus + Griphobilharzia plus the marine turtle blood flukes and schistosomes). Pending a forthcoming emended morphological diagnosis of the family, the clade including Spirorchis spp., paraphyletic Spirhapalum, Vasotrema, Baracktrema, and Unicaecum is a likely placeholder for "Spirorchiidae Stunkard, 1921 " (type genus Spirorchis MacCallum, 1918 ; type species Spirorchis innominatus Ward, 1921 ). The present study comprises the 17th blood fluke known to infect geoemydid turtles and the first proposal of a new genus of

  7. Tracking the fate of iron in early development of human blood flukes

    PubMed Central

    Jones, Malcolm K.; McManus, Donald P.; Sivadorai, Padma; Glanfield, Amber; Moertel, Luke; Belli, Sabina I.; Gobert, Geoffrey N.

    2007-01-01

    Iron (Fe) is an important trace element found in nearly all organisms, and is used as a cofactor in many biological reactions. One role for Fe in some invertebrates is in stabilization of extracellular matrices. The human blood fluke, Schistosoma japonicum, is responsible for significant human disease in developing and tropical nations. Disease in humans arises from host immunological reaction to parasite eggs that lodge in tissues. Schistosomes require Fe for development in their hosts, and store abundant Fe in vitelline (eggshell-forming) cells of the female system. The understanding of Fe metabolism and functionality are aspects of its biology that may be exploited in future therapeutics. The biology of Fe stores in vitelline cells of S. japonicum was investigated to illuminate possible functions of this element in early development of these parasites. Vitelline Fe is stored in yolk ferritin that is upregulated in females and is also expressed at low levels in egg-stages and adult males. Laser microdissection microscopy, coupled with reverse transcriptase- and real time-PCR amplification of schistosome ferritin sequences, confirmed that the vitelline cells are the likely progenitor cells of yolk ferritin. Assessment of Fe concentrations in whole male and whole female adult worms, eggs and purified eggshells by colorimetric assays and mass spectroscopy demonstrated higher levels of Fe in the female parasite, but also high levels of the element in whole parasite eggs and purified eggshell. Qualitative energy dispersive spectroscopy of purified eggshells, revealed that Fe is abundant in the eggshell, the matrix of which is composed of heavily cross-linked eggshell precursor proteins. Thus, vitelline stores of Fe are implicated in eggshell cross-linking in platyhelminths. These observations emphasise the importance of Fe in schistosome metabolism and egg formation and suggest new avenues for disruption of egg formation in these pathogenic parasites. PMID:17556009

  8. Tracking the fate of iron in early development of human blood flukes.

    PubMed

    Jones, Malcolm K; McManus, Donald P; Sivadorai, Padma; Glanfield, Amber; Moertel, Luke; Belli, Sabina I; Gobert, Geoffrey N

    2007-01-01

    Iron (Fe) is an important trace element found in nearly all organisms, and is used as a cofactor in many biological reactions. One role for Fe in some invertebrates is in stabilization of extracellular matrices. The human blood fluke, Schistosoma japonicum, is responsible for significant human disease in developing and tropical nations. Disease in humans arises from host immunological reaction to parasite eggs that lodge in tissues. Schistosomes require Fe for development in their hosts, and store abundant Fe in vitelline (eggshell-forming) cells of the female system. The understanding of Fe metabolism and functionality are aspects of its biology that may be exploited in future therapeutics. The biology of Fe stores in vitelline cells of S. japonicum was investigated to illuminate possible functions of this element in early development of these parasites. Vitelline Fe is stored in yolk ferritin that is upregulated in females and is also expressed at low levels in egg-stages and adult males. Laser microdissection microscopy, coupled with reverse transcriptase- and real time-PCR amplification of schistosome ferritin sequences, confirmed that the vitelline cells are the likely progenitor cells of yolk ferritin. Assessment of Fe concentrations in whole male and whole female adult worms, eggs and purified eggshells by colorimetric assays and mass spectroscopy demonstrated higher levels of Fe in the female parasite, but also high levels of the element in whole parasite eggs and purified eggshell. Qualitative energy dispersive spectroscopy of purified eggshells, revealed that Fe is abundant in the eggshell, the matrix of which is composed of heavily cross-linked eggshell precursor proteins. Thus, vitelline stores of Fe are implicated in eggshell cross-linking in platyhelminths. These observations emphasise the importance of Fe in schistosome metabolism and egg formation and suggest new avenues for disruption of egg formation in these pathogenic parasites.

  9. De novo transcriptomic analysis of the female and male adults of the blood fluke Schistosoma turkestanicum.

    PubMed

    Liu, Guo-Hua; Xu, Min-Jun; Chang, Qiao-Cheng; Gao, Jun-Feng; Wang, Chun-Ren; Zhu, Xing-Quan

    2016-03-11

    Schistosoma turkestanicum is a parasite of considerable veterinary importance as an agent of animal schistosomiasis in many countries, including China. The S. turkestanicum cercariae can also infect humans, causing cercarial dermatitis in many countries and regions of the world. In spite of its significance as a pathogen of animals and humans, there is little transcriptomic and genomic data in the public databases. Herein, we performed the transcriptome Illumina RNA sequencing (RNA-seq) of adult males and females of S. turkestanicum and de novo transcriptome assembly. Approximately 81.1 (female) and 80.5 (male) million high-quality clean reads were obtained and then 29,526 (female) and 41,346 (male) unigenes were assembled. A total of 34,624 unigenes were produced from S. turkestanicum females and males, with an average length of 878 nucleotides (nt) and N50 of 1480 nt. Of these unigenes, 25,158 (72.7 %) were annotated by blast searches against the NCBI non-redundant protein database. Among these, 21,995 (63.5 %), 22,189 (64.1 %) and 13,754 (39.7 %) of the unigenes had significant similarity in the NCBI non-redundant protein (NR), non-redundant nucleotide (NT) and Swiss-Prot databases, respectively. In addition, 3150 unigenes were identified to be expressed specifically in females and 1014 unigenes were identified to be expressed specifically in males. Interestingly, several pathways associated with gonadal development and sex maintenance were found, including the Wnt signaling pathway (103; 2 %) and progesterone-mediated oocyte maturation (77; 1.5 %). The present study characterized and compared the transcriptomes of adult female and male blood fluke, S. turkestanicum. These results will not only serve as valuable resources for future functional genomics studies to understand the molecular aspects of S. turkestanicum, but also will provide essential information for ongoing whole genome sequencing efforts on this pathogenic blood fluke.

  10. EVIDENCE OF DIVERSITY, SITE AND HOST SPECIFICITY OF SEA TURTLE BLOOD FLUKES (DIGENEA: SCHISTOSOMATOIDEA: "SPIRORCHIIDAE"): A MOLECULAR PROSPECTING STUDY.

    PubMed

    Stacy, Brian A; Chapman, Phoebe A; Foley, Allen M; Greiner, Ellis C; Herbst, Lawrence H; Bolten, Alan B; Klein, Paul A; Manire, Charles A; Jacobson, Elliott R

    2017-08-17

    Neospirorchis (Digenea: "Spirorchiidae") are blood flukes of sea turtles. Trematodes tentatively identified as Neospirorchis sp. infect various sites within sea turtles inhabiting waters of the southeastern United States, but efforts to obtain specimens adequate for morphologic study has proven difficult. Two genetic targets, the internal transcribed spacer region of the ribosomal RNA gene and the partial mitochrondrial cytochrome c oxidase subunit I gene, were used to investigate potential diversity among parasite specimens collected from stranded sea turtles. Sequence data were obtained from 215 trematode and egg specimens collected from 92 individual free-ranging cheloniid sea turtles comprising 4 host species. Molecular analysis yielded over 20 different genotypes. We were able to assign 1 genotype to 1 of the 2 recognized species, Neospirorchis pricei Manter and Larson, 1950. In many examples, genotypes exhibited host and site specificity. Our findings indicate considerable diversity of parasites resembling Neospirorchis with evidence of a number of uncharacterized blood flukes that require additional study.

  11. Co-dispersal of the blood fluke Schistosoma japonicum and Homo sapiens in the Neolithic Age

    PubMed Central

    Yin, Mingbo; Zheng, Hong-Xiang; Su, Jing; Feng, Zheng; McManus, Donald P.; Zhou, Xiao-Nong; Jin, Li; Hu, Wei

    2015-01-01

    The global spread of human infectious diseases is of considerable public health and biomedical interest. Little is known about the relationship between the distribution of ancient parasites and that of their human hosts. Schistosoma japonicum is one of the three major species of schistosome blood flukes causing the disease of schistosomiasis in humans. The parasite is prevalent in East and Southeast Asia, including the People’s Republic of China, the Philippines and Indonesia. We studied the co-expansion of S. japonicum and its human definitive host. Phylogenetic reconstruction based on complete mitochondrial genome sequences showed that S. japonicum radiated from the middle and lower reaches of the Yangtze River to the mountainous areas of China, Japan and Southeast Asia. In addition, the parasite experienced two population expansions during the Neolithic agriculture era, coinciding with human migration and population growth. The data indicate that the advent of rice planting likely played a key role in the spread of schistosomiasis in Asia. Moreover, the presence of different subspecies of Oncomelania hupensis intermediate host snails in different localities in Asia allowed S. japonicum to survive in new rice-planting areas, and concurrently drove the intraspecies divergence of the parasite. PMID:26686813

  12. HIV-1 Integrates Widely throughout the Genome of the Human Blood Fluke Schistosoma mansoni

    PubMed Central

    Mann, Victoria H.; Dubrovsky, Larisa; Yan, Hong-bin; Huckvale, Thomas; Protasio, Anna V.; Pushkarsky, Tatiana; Iordanskiy, Sergey; Bukrinsky, Michael I.

    2016-01-01

    Schistosomiasis is the most important helminthic disease of humanity in terms of morbidity and mortality. Facile manipulation of schistosomes using lentiviruses would enable advances in functional genomics in these and related neglected tropical diseases pathogens including tapeworms, and including their non-dividing cells. Such approaches have hitherto been unavailable. Blood stream forms of the human blood fluke, Schistosoma mansoni, the causative agent of the hepatointestinal schistosomiasis, were infected with the human HIV-1 isolate NL4-3 pseudotyped with vesicular stomatitis virus glycoprotein. The appearance of strong stop and positive strand cDNAs indicated that virions fused to schistosome cells, the nucleocapsid internalized and the RNA genome reverse transcribed. Anchored PCR analysis, sequencing HIV-1-specific anchored Illumina libraries and Whole Genome Sequencing (WGS) of schistosomes confirmed chromosomal integration; >8,000 integrations were mapped, distributed throughout the eight pairs of chromosomes including the sex chromosomes. The rate of integrations in the genome exceeded five per 1,000 kb and HIV-1 integrated into protein-encoding loci and elsewhere with integration bias dissimilar to that of human T cells. We estimated ~ 2,100 integrations per schistosomulum based on WGS, i.e. about two or three events per cell, comparable to integration rates in human cells. Accomplishment in schistosomes of post-entry processes essential for HIV-1replication, including integrase-catalyzed integration, was remarkable given the phylogenetic distance between schistosomes and primates, the natural hosts of the genus Lentivirus. These enigmatic findings revealed that HIV-1 was active within cells of S. mansoni, and provided the first demonstration that HIV-1 can integrate into the genome of an invertebrate. PMID:27764257

  13. HIV-1 Integrates Widely throughout the Genome of the Human Blood Fluke Schistosoma mansoni.

    PubMed

    Suttiprapa, Sutas; Rinaldi, Gabriel; Tsai, Isheng J; Mann, Victoria H; Dubrovsky, Larisa; Yan, Hong-Bin; Holroyd, Nancy; Huckvale, Thomas; Durrant, Caroline; Protasio, Anna V; Pushkarsky, Tatiana; Iordanskiy, Sergey; Berriman, Matthew; Bukrinsky, Michael I; Brindley, Paul J

    2016-10-01

    Schistosomiasis is the most important helminthic disease of humanity in terms of morbidity and mortality. Facile manipulation of schistosomes using lentiviruses would enable advances in functional genomics in these and related neglected tropical diseases pathogens including tapeworms, and including their non-dividing cells. Such approaches have hitherto been unavailable. Blood stream forms of the human blood fluke, Schistosoma mansoni, the causative agent of the hepatointestinal schistosomiasis, were infected with the human HIV-1 isolate NL4-3 pseudotyped with vesicular stomatitis virus glycoprotein. The appearance of strong stop and positive strand cDNAs indicated that virions fused to schistosome cells, the nucleocapsid internalized and the RNA genome reverse transcribed. Anchored PCR analysis, sequencing HIV-1-specific anchored Illumina libraries and Whole Genome Sequencing (WGS) of schistosomes confirmed chromosomal integration; >8,000 integrations were mapped, distributed throughout the eight pairs of chromosomes including the sex chromosomes. The rate of integrations in the genome exceeded five per 1,000 kb and HIV-1 integrated into protein-encoding loci and elsewhere with integration bias dissimilar to that of human T cells. We estimated ~ 2,100 integrations per schistosomulum based on WGS, i.e. about two or three events per cell, comparable to integration rates in human cells. Accomplishment in schistosomes of post-entry processes essential for HIV-1replication, including integrase-catalyzed integration, was remarkable given the phylogenetic distance between schistosomes and primates, the natural hosts of the genus Lentivirus. These enigmatic findings revealed that HIV-1 was active within cells of S. mansoni, and provided the first demonstration that HIV-1 can integrate into the genome of an invertebrate.

  14. Three new species of blood flukes (Digenea: Aporocotylidae) infecting pufferfishes (Teleostei: Tetraodontidae) from off Bali, Indonesia.

    PubMed

    Yong, R Q-Y; Cutmore, S C; Bray, R A; Miller, T L; Semarariana, I W Y; Palm, H W; Cribb, T H

    2016-10-01

    We describe three new species of blood flukes (Aporocotylidae) and propose their classification within the genus Psettarium Goto & Ozaki, 1929. All three species were collected from the circulatory systems of pufferfishes caught off Bali, central Indonesia. Psettarium pulchellum n. sp. was found in the gills of both the narrow-lined puffer (Arothron manilensis de Procé) and the spiny blaasop (Tylerius spinosissimus Regan), while P. ogawai n. sp. and P. jimbaranense n. sp. were found in the gills of the reticulated puffer (Arothron reticularis Bloch & Schneider). The morphological characteristics of these taxa necessitated emendation of the diagnosis for the genus Psettarium, to accommodate the presence of an oral sucker, multiple or entirely post-caecal testes and a degenerate posterior testis. Features such as proportion of body length occupied by the oesophagus, and posterior caeca being ≥7× the length of anterior caeca, are no longer regarded as useful genus-level characters. Additionally, Sasala nolani is reassigned to this genus as Psettarium nolani n. comb. In phylogenetic analyses of the 28S and ITS2 rDNA regions, all three new taxa form a well-supported clade, together with Psettarium sinense and Psettarium nolani n. comb., the two other species of tetraodontid-infecting aporocotylids for which comparative rDNA data were available. The short branch lengths within this clade, despite dramatic morphological differences between the five species, suggest that rapid morphological diversification has occurred among the tetraodontid-infecting aporocotylids. The genus Psettarium has long been considered problematic. Further commentary is given on the history of this genus and how the issues presented might be resolved.

  15. Prolyl Oligopeptidase from the Blood Fluke Schistosoma mansoni: From Functional Analysis to Anti-schistosomal Inhibitors

    PubMed Central

    Fajtová, Pavla; Štefanić, Saša; Hradilek, Martin; Dvořák, Jan; Vondrášek, Jiří; Jílková, Adéla; Ulrychová, Lenka; McKerrow, James H.; Caffrey, Conor R.; Mareš, Michael; Horn, Martin

    2015-01-01

    Background Blood flukes of the genus Schistosoma cause schistosomiasis, a parasitic disease that infects over 240 million people worldwide, and for which there is a need to identify new targets for chemotherapeutic interventions. Our research is focused on Schistosoma mansoni prolyl oligopeptidase (SmPOP) from the serine peptidase family S9, which has not been investigated in detail in trematodes. Methodology/Principal Findings We demonstrate that SmPOP is expressed in adult worms and schistosomula in an enzymatically active form. By immunofluorescence microscopy, SmPOP is localized in the tegument and parenchyma of both developmental stages. Recombinant SmPOP was produced in Escherichia coli and its active site specificity investigated using synthetic substrate and inhibitor libraries, and by homology modeling. SmPOP is a true oligopeptidase that hydrolyzes peptide (but not protein) substrates with a strict specificity for Pro at P1. The inhibition profile is analogous to those for mammalian POPs. Both the recombinant enzyme and live worms cleave host vasoregulatory, proline-containing hormones such as angiotensin I and bradykinin. Finally, we designed nanomolar inhibitors of SmPOP that induce deleterious phenotypes in cultured schistosomes. Conclusions/Significance We provide the first localization and functional analysis of SmPOP together with chemical tools for measuring its activity. We briefly discuss the notion that SmPOP, operating at the host-parasite interface to cleave host bioactive peptides, may contribute to the survival of the parasite. If substantiated, SmPOP could be a new target for the development of anti-schistosomal drugs. PMID:26039195

  16. SmCL3, a Gastrodermal Cysteine Protease of the Human Blood Fluke Schistosoma mansoni

    PubMed Central

    Dvořák, Jan; Mashiyama, Susan T.; Sajid, Mohammed; Braschi, Simon; Delcroix, Melaine; Schneider, Eric L.; McKerrow, Wilson H.; Bahgat, Mahmoud; Hansell, Elizabeth; Babbitt, Patricia C.; Craik, Charles S.; McKerrow, James H.; Caffrey, Conor R.

    2009-01-01

    Background Blood flukes of the genus Schistosoma are platyhelminth parasites that infect 200 million people worldwide. Digestion of nutrients from the host bloodstream is essential for parasite development and reproduction. A network of proteolytic enzymes (proteases) facilitates hydrolysis of host hemoglobin and serum proteins. Methodology/Principal Findings We identified a new cathepsin L termed SmCL3 using PCR strategies based on S. mansoni EST sequence data. An ortholog is present in Schistosoma japonicum. SmCL3 was heterologously expressed as an active enzyme in the yeast, Pichia pastoris. Recombinant SmCL3 has a broad pH activity range against peptidyl substrates and is inhibited by Clan CA protease inhibitors. Consistent with a function in degrading host proteins, SmCL3 hydrolyzes serum albumin and hemoglobin, is localized to the adult gastrodermis, and is expressed mainly in those life stages infecting the mammalian host. The predominant form of SmCL3 in the parasite exists as a zymogen, which is unusual for proteases. This zymogen includes an unusually long prodomain with alpha helical secondary structure motifs. The striking specificity of SmCL3 for amino acids with large aromatic side chains (Trp and Tyr) at the P2 substrate position, as determined with positional scanning-synthetic combinatorial library, is consistent with a molecular model that shows a large and deep S2 pocket. A sequence similarity network (SSN) view clusters SmCL3 and other cathepsins L in accordance with previous large-scale phylogenetic analyses that identify six super kingdoms. Conclusions/Significance SmCL3 is a gut-associated cathepsin L that may contribute to the network of proteases involved in degrading host blood proteins as nutrients. Furthermore, this enzyme exhibits some unusual sequence and biophysical features that may result in additional functions. The visualization of network inter-relationships among cathepsins L suggests that these enzymes are suitable

  17. MicroRNAs Are Involved in the Regulation of Ovary Development in the Pathogenic Blood Fluke Schistosoma japonicum

    PubMed Central

    Hu, Chao; Peng, Jinbiao; Luo, Rong; Zhou, Chunjing; Liu, Juntao; Lin, Jiaojiao; Jin, Youxin; Davis, Richard E.; Cheng, Guofeng

    2016-01-01

    Schistosomes, blood flukes, are an important global public health concern. Paired adult female schistosomes produce large numbers of eggs that are primarily responsible for the disease pathology and critical for dissemination. Consequently, understanding schistosome sexual maturation and egg production may open novel perspectives for intervening with these processes to prevent clinical symptoms and to interrupt the life-cycle of these blood-flukes. microRNAs (miRNAs) are key regulators of many biological processes including development, cell proliferation, metabolism, and signal transduction. Here, we report on the identification of Schistosoma japonicum miRNAs using small RNA deep sequencing in the key stages of male-female pairing, gametogenesis, and egg production. We identified 38 miRNAs, including 10 previously unknown miRNAs. Eighteen of the miRNAs were differentially expressed between male and female schistosomes and during different stages of sexual maturation. We identified 30 potential target genes for 16 of the S. japonicum miRNAs using antibody-based pull-down assays and bioinformatic analyses. We further validated some of these target genes using either in vitro luciferase assays or in vivo miRNA suppression experiments. Notably, suppression of the female enriched miRNAs bantam and miR-31 led to morphological alteration of ovaries in female schistosomes. These findings uncover key roles for specific miRNAs in schistosome sexual maturation and egg production. PMID:26871705

  18. A new blood fluke, Parasanguinicola vastispina gen. nov., sp. nov. (Trematoda: Sanguinicolidae), from sea bass Lates calcarifer (Centropomidae) cultured in Malaysia.

    PubMed

    Herbert, B W; Shaharom, F M

    1995-01-01

    A new sanguinicolid blood fluke, Parasanguinicola vastispina, is described from sea bass Lates calcarifer cultured in Malaysia. It is distinguished by its massive armature and widely spaced genital pores, the female pore being pre-ovarian. P. vastispina inhabits the branchial arteries, dorsal aorta, mesenteric venules and renal artery of its host. No pathological effect was observed in infected fish.

  19. Developmental stages of fish blood flukes, Cardicola forsteri and Cardicola opisthorchis (Trematoda: Aporocotylidae), in their polychaete intermediate hosts collected at Pacific bluefin tuna culture sites in Japan.

    PubMed

    Ogawa, Kazuo; Shirakashi, Sho; Tani, Kazuki; Shin, Sang Phil; Ishimaru, Katsuya; Honryo, Tomoki; Sugihara, Yukitaka; Uchida, Hiro'omi

    2017-02-01

    Farming of Pacific bluefin tuna (PBT), Thunnus orientalis, is a rapidly growing industry in Japan. Aporocotylid blood flukes of the genus Cardicola comprising C. orientalis, C. opisthorchis and C. forsteri are parasites of economic importance for PBT farming. Recently, terebellid polychaetes have been identified as the intermediate hosts for all these parasites. We collected infected polychaetes, Terebella sp., the intermediate host of C. opisthorchis, from ropes and floats attached to tuna cages in Tsushima, Nagasaki Prefecture, Japan. Also, Neoamphitrite vigintipes (formerly as Amphitrite sp. sensu Shirakashi et al., 2016), the intermediate host of C. forsteri, were collected from culture cages in Kushimoto, Wakayama Prefecture, Japan. The terebellid intermediate hosts harbored the sporocysts and cercariae in their body cavity. Developmental stages of these blood flukes were molecularly identified using species specific PCR primers. In this paper, we describe the cercaria and sporocyst stages of C. opisthorchis and C. forsteri and compare their morphological characteristics among three Cardicola blood flukes infecting PBT. We also discuss phylogenetic relations of the six genera of the terebellid intermediate hosts (Artacama, Lanassa, Longicarpus, Terebella, Nicolea and Neoamphitrite) of blood flukes infecting marine fishes, based on their morphological characters.

  20. A natural focus of the blood fluke Orientobilharzia turkestanica (Skrjabin, 1913) (Trematoda: Schistosomatidae) in red deer (Cervus elaphus) in Hungary.

    PubMed

    Majoros, Gábor; Dán, Adám; Erdélyi, Károly

    2010-06-24

    The large American liver fluke, Fascioloides magna - introduced to Europe before 1875 - was the first non-indigenous trematode to be detected in Hungarian cervids in 1995. As the most precious deer population became infected in the Gemenc game reserve a study has been launched to assess the extent and the effect of F. magna infections and to examine the options for the treatment of infected deer populations. Livers of red deer shot during regular hunting were submitted for the survey and were investigated by necropsy for the presence of F. magna and other liver dwelling trematodes. Recovered parasites were counted, sorted and stored in 70% ethanol. Unexpectedly, blood flukes were found in liver blood vessels at necropsy. They were identified as Orientobilharzia turkestanica (Skrjabin, 1913) by their morphological features as well as by molecular methods. This parasite is widespread in the middle belt of Asia from Korea to the eastern part of Turkey and infects mainly bovids. It was never found in red deer until now and this is the first report of its occurrence in Hungary and Europe. A subsequent search for the local intermediate host of O. turkestanica in the Gemenc area identified only the pulmonate snail Radix auricularia (Linnaeus, 1758) [syn: Lymnaea auricularia] as a vector capable of producing cercariae of this trematode. Cercariae of O. turkestanica were examined morphologically and were confirmed to be the larvae of this trematode by PCR. O. turkestanica appears to be fairly common in red deer of the Gemenc area. No clinical or pathological effect of the infection could be identified in this study. A form of cercarial dermatitis locally called "water mange" was formerly attributed to the larvae of avian shistosomes. It regularly occurred among fishermen fishing in shallow ponds remaining after floods along the Danube in the Gemenc area. This isolated habitat of O. turkestanica presents an exceptional opportunity to study epidemical situations of typical

  1. Successful parasitism of vector snail Biomphalaria glabrata by the human blood fluke (trematode) Schistosoma mansoni: a 2009 assessment

    PubMed Central

    Bayne, Christopher J.

    2009-01-01

    Schistosomiasis, caused by infections by human blood flukes (Trematoda), continues to disrupt the lives of over 200,000,000 people in over 70 countries, inflicting misery and precluding the individuals’ otherwise reasonable expectations of productive lives. Infection requires contact with freshwater in which infected snails (the intermediate hosts of schistosomes) have released cercariae larvae. Habitats suitable for the host snails continue to expand as a consequence of water resource development. No vaccine is available, and the emergence and spread of resistance to the single licensed schistosomicide drug would be devastating. Since human infections would cease if parasite infections in snails were prevented, efforts are being made to discover requirements of intra-molluscan development of these parasites. Wherever blood flukes occur, naturally resistant conspecific snails are present. To understand the mechanisms used by parasites to ensure their survival in immunocompetent hosts, one must comprehend the internal defense mechanisms that are available to the host. For one intermediate host snail (Biomphalaria glabrata) and trematodes for which it serves as vector, molecular genetic and proteomic surveys for genes and proteins influencing the outcomes on infections are yielding lists of candidates. A comparative approach drawing on data from studies in divergent species provides a robust basis for hypothesis generation to drive decisions as to which candidates merit detailed further investigation. For example, reactive oxygen and nitrogen species are known mediators or effectors in battles between infectious agents and their hosts. An approach targeting genes involved in relevant pathways has been fruitful in the Schistosoma mansoni-B. glabrata parasitism, leading to discovery of a functionally relevant gene set (encoding enzymes responsible for the leukocyte respiratory burst) that associates significantly with host resistance phenotype. This review summarizes

  2. Exploiting osmosis for blood cell sorting.

    PubMed

    Parichehreh, Vahidreza; Estrada, Rosendo; Kumar, Srikanth Suresh; Bhavanam, Kranthi Kumar; Raj, Vinay; Raj, Ashok; Sethu, Palaniappan

    2011-06-01

    Blood is a valuable tissue containing cellular populations rich in information regarding the immediate immune and inflammatory status of the body. Blood leukocytes or white blood cells (WBCs) provide an ideal sample to monitor systemic changes and understand molecular signaling mechanisms in disease processes. Blood samples need to be processed to deplete contaminating erythrocytes or red blood cells (RBCs) and sorted into different WBC sub-populations prior to analysis. This is typically accomplished using immuno-affinity protocols which result in undesirable activation. An alternative is size based sorting which by itself is unsuitable for WBCs sorting due to size overlap between different sub-populations. To overcome this limitation, we investigated the possibility of using controlled osmotic exposure to deplete and/or create a differential size increase between WBC populations. Using a new microfluidic cell docking platform, the response of RBCs and WBCs to deionized (DI) water was evaluated. Time lapse microscopy confirms depletion of RBCs within 15 s and creation of > 3 μm size difference between lymphocytes, monocytes and granulocytes. A flow through microfluidic device was also used to expose different WBCs to DI water for 30, 60 and 90 s to quantify cell loss and activation. Results confirm preservation of ~100% of monocytes, granulocytes and loss of ~30% of lymphocytes (mostly CD3+/CD4+) with minimal activation. These results indicate feasibility of this approach for monocyte, granulocyte and lymphocyte (sub-populations) isolation based on size.

  3. Evidence that blood flukes (Trematoda: Aporocotylidae) of chondrichthyans infect bivalves as intermediate hosts: indications of an ancient diversification of the Schistosomatoidea.

    PubMed

    Cribb, Thomas H; Chick, Rowan C; O'Connor, Wayne; O'Connor, Stephan; Johnson, Daniel; Sewell, Kim B; Cutmore, Scott C

    2017-08-12

    Blood flukes (Aporocotylidae) of actinopterygians (bony fishes) have been shown to infect freshwater gastropods and marine polychaetes as intermediate hosts. However, no life cycle is known for any aporocotylid of chondrichthyans (cartilaginous fishes) and no adult aporocotylid has been linked to a cercaria infecting a bivalve. Here we report two novel infections that fill these gaps. Cercariae consistent with the family Aporocotylidae were found developing in sporocysts in the gonad of the surf pipi, Donax deltoides Lamarck, 1818 (Bivalvia: Donacidae), from Stockton Beach, central New South Wales, Australia. Adult aporocotylids were found in the heart of the giant shovelnose ray, Glaucostegus typus (Anonymous [Bennett], 1830), from Moreton Bay, southeastern Queensland, Australia. Phylogenetic analyses of the 28S rDNA region generated from the new specimens resulted in phylograms in which the two parasites form a strongly supported clade with Chimaerohemecus trondheimensis van der Land, 1967, the only aporocotylid known from a holocephalan and the only other chondrichthyan-infecting aporocotylid for which sequence data are available. Most marine aporocotylids of actinopterygians also form a strongly supported clade. These findings lead us to hypothesise that the aporocotylids of chondrichthyans are distinct from all other blood flukes in infecting bivalves as intermediate hosts. Putative cophyly between three major blood fluke clades and both definitive and intermediate host groups is consistent with diversification of the Schistosomatoidea over 400million years ago. Copyright © 2017 Australian Society for Parasitology. All rights reserved.

  4. Blood flukes (Digenea: Aporocotylidae) of walking catfishes (Siluriformes: Clariidae): new genus and species from the Mekong River (Vietnam) with comments on related catfish aporocotylids.

    PubMed

    Truong, Triet Nhat; Bullard, Stephen A

    2013-07-01

    Nomasanguinicola canthoensis gen. et sp. n. infects the branchial vessels of bighead catfish, Clarias macrocephalus Günther (Siluriformes: Clariidae), in the Mekong River near Can Tho, southern Vietnam. Nomasanguinicola differs from all other genera of fish blood flukes (Digenea: Aporocotylidae) by the combination of lacking body spines and by having an anterior sucker with two flanking columns of large denticles, an intestine comprising several short papilla-like caeca, an inverse U-shaped uterus, and an ootype located near the separate genital pores. The new species has an ootype that is posterior to the level of the female genital pore. That feature most easily differentiates it from the only other putative aporocotylid species having an anterior sucker with two flanking columns of large denticles, Plehniella dentata Paperna, 1964 and Sanguinicola clarias Imam, Marzouk, Hassan et Itman, 1984, which have an ootype that is lateral (P. dentata) or anterior (S. clarias) to the level of the female genital pore. These two species apparently lack extant type materials, infect North African catfish, Clarias gariepinus (Burchell), and herein are considered incertae sedis, but likely comprise species of Nomasanguinicola. An updated list of hosts, sites of infection and geographic localities for the six species and three genera of blood flukes that mature in catfishes is provided. The new species is the first fish blood fluke recorded from Vietnam and only the third reported from a walking catfish (Clariidae).

  5. Pharmacological and autoradiographical characterization of serotonin transporter-like activity in sporocysts of the human blood fluke, Schistosoma mansoni.

    PubMed

    Boyle, J P; Hillyer, J F; Yoshino, T P

    2003-08-01

    The present study focuses on the role of the biogenic monoamine serotonin (5-hydroxytryptamine) in the biology of sporocyst stages of the human blood fluke, Schistosoma mansoni, and its importance during obligate development within its snail host Biomphalaria glabrata. Based on previous work demonstrating that snails infected with S. mansoni have reduced levels of 5-hydroxytryptamine, we hypothesized that sporocysts actively transport this molecule from the host milieu. Intact sporocysts isolated in vitro take up exogenous 5-hydroxytryptamine via a high-affinity mechanism (K(m)=1.4 micromol l(-1)), and this serotonin transporter-like activity is dependent upon extracellular Na(+) and Cl(-) and is highly sensitive to previously characterized serotonin transporter inhibitors. Autoradiography suggests that transported [(3)H]5-hydroxytryptamine localizes within the body of the sporocyst, and in many cases is found in apical gland cells. Moreover, serotonin transporter-like activity is absent in free-swimming miracidia, the infective stage for the snail host, and the increase in larval serotonin transporter-like activity after miracidium-to-sporocyst transformation is accompanied by a corresponding decrease in steady-state levels of transcripts for tryptophan hydroxylase, the rate-limiting enzyme in serotonin biosynthesis. Overall our data suggest that S. mansoni larvae express surface-exposed serotonin transporter-like molecules, and that the transition from free-living miracidium to parasitic mother sporocyst is characterized by an increased dependence upon exogenous 5-hydroxytryptamine.

  6. Characterization of MicroRNAs from Orientobilharzia turkestanicum, a Neglected Blood Fluke of Human and Animal Health Significance

    PubMed Central

    Fu, Jing-Hua; Nisbet, Alasdair J.; Chang, Qiao-Cheng; Zhou, Dong-Hui; Huang, Si-Yang; Zou, Feng-Cai; Zhu, Xing-Quan

    2012-01-01

    The neglected blood flukes Orientobilharzia spp. belonging to the Platyhelminthes, infect animals in a number of countries of the world, and cause cercarial dermatitis in humans, as well as significant diseases and even death in economically-important animals. MicroRNAs (miRNAs) are now considered to be a key mechanism of gene regulation. Herein, we investigated the global miRNA expression profile of adult O. turkestanicum using next-generation sequencing technology and real-time quantitative PCR, to gain further information on the role of these molecules in host invasion and the parasitic lifestyle of this species. A total of 13.48 million high quality reads were obtained out of 13.78 million raw sequencing reads, with 828 expressed miRNAs identified. Phylogenetic analysis showed that the miRNAs of O. turkestanicum were still rapidly evolving and there was a “directed mutation” pattern compared with that of other species. Target mRNAs were successfully predicted to 518 miRNAs. These targets included energy metabolism, transcription initiation factors, signal transduction, growth factor receptors. miRNAs targeting egg proteins, including major egg antigen p40, and heat shock proteins were also found. Enrichment analysis indicated enrichment for mRNAs involved in catalytic, binding, transcription regulators and translation regulators. The present study represented the first large-scale characterization of O. turkestanicum miRNAs, which provides novel resources for better understanding the complex biology of this zoonotic parasite, which, in turn, has implications for the effective control of the disease it causes. PMID:23071694

  7. Elucidation of the first definitively identified life cycle for a marine turtle blood fluke (Trematoda: Spirorchiidae) enables informed control.

    PubMed

    Cribb, Thomas H; Crespo-Picazo, Jose L; Cutmore, Scott C; Stacy, Brian A; Chapman, Phoebe A; García-Párraga, Daniel

    2017-01-01

    Blood flukes of the family Spirorchiidae are significant pathogens of both free-ranging and captive marine turtles. Despite a significant proportion of marine turtle mortality being attributable to spirorchiid infections, details of their life cycles remain almost entirely unknown. Here we report on the molecular elucidation of the complete life cycle of a marine spirorchiid, identified as Amphiorchis sp., infecting vermetid gastropods and captive hatched neonate Caretta caretta in the Oceanogràfic Aquarium, in Valencia, Spain. Specimens of a vermetid gastropod, Thylaeodus cf. rugulosus (Monterosato, 1878), collected from the aquarium filtration system housing diseased C. caretta, were infected with sporocysts and cercariae consistent with the family Spirorchiidae. We generated rDNA sequence data [internal transcribed spacer 2 (ITS2) and partial 28S rDNA] from infections from the vermetid which were identical to sequences generated from eggs from the serosa of the intestine of neonate C. caretta, and an adult spirorchiid from the liver of a C. caretta from Florida, USA. Given the reliability of these markers in the delineation of trematode species, we consider all three stages to represent the same species and tentatively identify it as a species of Amphiorchis Price, 1934. The source of infection at the Oceanogràfic Foundation Rehabilitation Centre, Valencia, Spain, is inferred to be an adult C. caretta from the western Mediterranean being rehabilitated in the same facility. Phylogenetic analysis suggests that this Amphiorchis sp. is closely related to other spirorchiids of marine turtles (species of Carettacola Manter & Larson, 1950, Hapalotrema Looss, 1899 and Learedius Price, 1934). We discuss implications of the present findings for the control of spirorchiidiasis in captivity, for the better understanding of epidemiology in wild individuals, and the elucidation of further life cycles. Copyright © 2016 Australian Society for Parasitology. Published by

  8. An approach to revealing blood fluke life cycles, taxonomy, and diversity: provision of key reference data including DNA sequence from single life cycle stages.

    PubMed

    Brant, Sara V; Morgan, Jess A T; Mkoji, Gerald M; Snyder, Scott D; Rajapakse, R P V Jayanthe; Loker, Eric S

    2006-02-01

    Revealing diversity among extant blood flukes, and the patterns of relationships among them, has been hindered by the difficulty of determining if specimens described from different life cycle stages, hosts, geographic localities, and times represent the same or different species. Persistent collection of all available life cycle stages and provision of exact collection localities, host identification, reference DNA sequences for the parasite, and voucher specimens eventually will provide the framework needed to piece together individual life cycles and facilitate reconciliation with classical taxonomic descriptions, including those based on single life cycle stages. It also provides a means to document unique or rare species that might only ever be recovered from a single life cycle stage. With an emphasis on the value of new information from field collections of any available life cycle stages, here we provide data for several blood fluke cercariae from freshwater snails from Kenya, Uganda, and Australia. Similar data are provided for adult worms of Macrobilharzia macrobilharzia and miracidia of Bivitellobilharzia nairi. Some schistosome and sanguinicolid cercariae that we recovered have peculiar morphological features, and our phylogenetic analyses (18S and 28S rDNA and mtDNA CO1) suggest that 2 of the new schistosome specimens likely represent previously unknown lineages. Our results also provide new insights into 2 of the 4 remaining schistosome genera yet to be extensively characterized with respect to their position in molecular phylogenies, Macrobilharzia and Bivitellobilharzia. The accessibility of each life cycle stage is likely to vary dramatically from one parasite species to the next, and our examples validate the potential usefulness of information gleaned from even one such stage, whatever it might be.

  9. AN APPROACH TO REVEALING BLOOD FLUKE LIFE CYCLES, TAXONOMY, AND DIVERSITY: PROVISION OF KEY REFERENCE DATA INCLUDING DNA SEQUENCE FROM SINGLE LIFE CYCLE STAGES

    PubMed Central

    Brant, Sara V.; Morgan, Jess A. T.; Mkoji, Gerald M.; Snyder, Scott D.; Rajapakse, R. P. V. Jayanthe; Loker, Eric S.

    2008-01-01

    Revealing diversity among extant blood flukes, and the patterns of relationships among them, has been hindered by the difficulty of determining if specimens described from different life cycle stages, hosts, geographic localities, and times represent the same or different species. Persistent collection of all available life cycle stages and provision of exact collection localities, host identification, reference DNA sequences for the parasite, and voucher specimens eventually will provide the framework needed to piece together individual life cycles and facilitate reconciliation with classical taxonomic descriptions, including those based on single life cycle stages. It also provides a means to document unique or rare species that might only ever be recovered from a single life cycle stage. With an emphasis on the value of new information from field collections of any available life cycle stages, here we provide data for several blood fluke cercariae from freshwater snails from Kenya, Uganda, and Australia. Similar data are provided for adult worms of Macrobilharzia macrobilharzia and miracidia of Bivitellobilharzia nairi. Some schistosome and sanguinicolid cercariae that we recovered have peculiar morphological features, and our phylogenetic analyses (18S and 28S rDNA and mtDNA CO1) suggest that 2 of the new schistosome specimens likely represent previously unknown lineages. Our results also provide new insights into 2 of the 4 remaining schistosome genera yet to be extensively characterized with respect to their position in molecular phylogenies, Macrobilharzia and Bivitellobilharzia. The accessibility of each life cycle stage is likely to vary dramatically from one parasite species to the next, and our examples validate the potential usefulness of information gleaned from even one such stage, whatever it might be. PMID:16629320

  10. Cytokine/chemokine secretion and proteomic identification of upregulated annexin A1 from peripheral blood mononuclear cells cocultured with the liver fluke Opisthorchis viverrini.

    PubMed

    Hongsrichan, Nuttanan; Intuyod, Kitti; Pinlaor, Porntip; Khoontawad, Jarinya; Yongvanit, Puangrat; Wongkham, Chaisiri; Roytrakul, Sittiruk; Pinlaor, Somchai

    2014-05-01

    We investigated the cytokine/chemokine secretions and alteration of protein expression from peripheral blood mononuclear cells (PBMCs) cocultured with adult liver flukes (Opisthorchis viverrini) for 6 to 24 h. PBMC-derived proteins were identified by two-dimensional electrophoresis and mass spectrometry, and the cytokines/chemokines in the supernatant were assessed using a cytokine array. Exposure to O. viverrini induced increases in secretion of proinflammatory cytokines, costimulating protein, adhesion molecules, and chemotactic chemokines relative to untreated controls. In contrast, secretion of the CD40 ligand, interleukin 16, and macrophage inflammatory protein 1β decreased. Proteomic analysis revealed that expression of 48 proteins was significantly altered in PBMCs stimulated with O. viverrini. Annexin A1 (ANXA1) was selected for further study, and immunoblotting showed upregulation of ANXA1 expression in PBMCs after 12 and 24 h coculture with liver flukes. In an in vivo study, transcription and translation of ANXA1 significantly increased in livers of hamsters infected with O. viverrini at 21 days and from 3 months onwards compared to normal controls. Interestingly, immunohistochemistry revealed that ANXA1 was present not only in the cytoplasm of inflammatory cells but also in the cytoplasm of cholangiocytes, which are in close contact with the parasite and its excretory/secretory products in the biliary system. Expression of ANXA1 increased with time concomitant with bile duct enlargement, bile duct formation, and epithelial cell proliferation. In conclusion, several cytokines/chemokines secreted by PBMCs and upregulation of ANXA1 in PBMCs and biliary epithelial cells might have a role in host defense against O. viverrini infection and tissue resolution of inflammation.

  11. Cytokine/Chemokine Secretion and Proteomic Identification of Upregulated Annexin A1 from Peripheral Blood Mononuclear Cells Cocultured with the Liver Fluke Opisthorchis viverrini

    PubMed Central

    Hongsrichan, Nuttanan; Intuyod, Kitti; Pinlaor, Porntip; Khoontawad, Jarinya; Yongvanit, Puangrat; Wongkham, Chaisiri; Roytrakul, Sittiruk

    2014-01-01

    We investigated the cytokine/chemokine secretions and alteration of protein expression from peripheral blood mononuclear cells (PBMCs) cocultured with adult liver flukes (Opisthorchis viverrini) for 6 to 24 h. PBMC-derived proteins were identified by two-dimensional electrophoresis and mass spectrometry, and the cytokines/chemokines in the supernatant were assessed using a cytokine array. Exposure to O. viverrini induced increases in secretion of proinflammatory cytokines, costimulating protein, adhesion molecules, and chemotactic chemokines relative to untreated controls. In contrast, secretion of the CD40 ligand, interleukin 16, and macrophage inflammatory protein 1β decreased. Proteomic analysis revealed that expression of 48 proteins was significantly altered in PBMCs stimulated with O. viverrini. Annexin A1 (ANXA1) was selected for further study, and immunoblotting showed upregulation of ANXA1 expression in PBMCs after 12 and 24 h coculture with liver flukes. In an in vivo study, transcription and translation of ANXA1 significantly increased in livers of hamsters infected with O. viverrini at 21 days and from 3 months onwards compared to normal controls. Interestingly, immunohistochemistry revealed that ANXA1 was present not only in the cytoplasm of inflammatory cells but also in the cytoplasm of cholangiocytes, which are in close contact with the parasite and its excretory/secretory products in the biliary system. Expression of ANXA1 increased with time concomitant with bile duct enlargement, bile duct formation, and epithelial cell proliferation. In conclusion, several cytokines/chemokines secreted by PBMCs and upregulation of ANXA1 in PBMCs and biliary epithelial cells might have a role in host defense against O. viverrini infection and tissue resolution of inflammation. PMID:24614660

  12. Human liver flukes.

    PubMed

    Harrington, David; Lamberton, Poppy H L; McGregor, Alastair

    2017-09-01

    Liver fluke infections occur in people worldwide. In some low-income regions, a combination of ecological, agricultural, and culinary factors leads to a very high prevalence of infection but, in higher-income regions, infections are uncommon. Infection is associated with substantial morbidity and several liver fluke species are recognised as biological carcinogens. Here, we review the epidemiology, clinical significance, and diagnostic and treatment strategies of human infection with these pathogens. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Where are the South American freshwater turtle blood flukes (Trematoda: Spirorchiidae)? The first morphological and molecular analysis of spirorchiid cercariae from freshwater snails in Brazil.

    PubMed

    Pinto, Hudson Alves; de Melo, Alan Lane; Brant, Sara Vanessa

    2015-12-01

    Trematodes belonging to the family Spirorchiidae are blood parasites mainly of turtles with a worldwide distribution. These flukes were recently reported in some marine turtles from South America, where the occurrence of spirorchiids in freshwater definitive and intermediate hosts is so far unknown. In the present study, three morphotypes of brevifurcate apharyngeate distome cercariae found in freshwater molluscs from an urban reservoir in Brazil were used for morphological and molecular (nuclear 28S rDNA) evaluation. Two morphotypes of cercariae, probably congeneric species, were found in 12/17,465 specimens of Biomphalaria spp. and differ from each other by body size and sequences (0.1%). They present morphology similar to North American freshwater spirorchiids (Spirorchis spp.), however surprisingly molecular data reveals that these lineages are more closely related to marine spirorchiids. A third species found in 2/777 Pomacea sp. differs morphologically from all previously described spirorchiid cercariae and genetically from spirorchiids with available sequences (16-19%), grouping in the phylogenetic tree with freshwater North American species. This is the first report of freshwater spirorchiids in South America and the first molecular confirmation of the involvement of a caenogastropod in the life cycle of spirorchiids.

  14. Discovery of intermediate hosts for two species of blood flukes Cardicola orientalis and Cardicola forsteri (Trematoda: Aporocotylidae) infecting Pacific bluefin tuna in Japan.

    PubMed

    Shirakashi, Sho; Tani, Kazuki; Ishimaru, Katsuya; Shin, Sang Phil; Honryo, Tomoki; Uchida, Hiro'omi; Ogawa, Kazuo

    2016-04-01

    Fish blood flukes (Aporocotylidae) are important pathogens of farmed finfish around the world. Among them, Cardicola spp. infecting farmed tuna are considered to be serious threats to tuna farming and have received tremendous attention. We conducted periodical samplings at a tuna farming site in Japan between January and May, 2015 to determine the life cycle of Cardicola spp. We collected over 4700 terebellid polychaetes from ropes, floats and frames of tuna culture cages and found nearly 400 infected worms. Sporocysts and cercariae found in Nicolea gracilibranchis were genetically identified as Cardicola orientalis by 28S and ITS2 ribosomal DNA sequences. This was the first discovery of the intermediate host for this parasite species. Infection prevalence and the abundance of N. gracilibranchis significantly varied between sampling points and the highest number of infected terebellids were collected from ropes. We also demonstrated morphologically and molecularly that asexual stages found in a single Amphitrite sp. (Terebellidae) and adult worms isolated from farmed juvenile tuna were Cardicola forsteri. This is the first report of C. forsteri in Pacific bluefin tuna (PBT) Thunnus orientalis in Japan. Our results demonstrated that all three species of Cardicola orientalis, C. forsteri and Cardicola opisthorchis exist in Japanese farmed PBTs and that they all use terebellid polychaetes as the intermediate hosts. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  15. Structural basis for the inhibition of histone deacetylase 8 (HDAC8), a key epigenetic player in the blood fluke Schistosoma mansoni.

    PubMed

    Marek, Martin; Kannan, Srinivasaraghavan; Hauser, Alexander-Thomas; Moraes Mourão, Marina; Caby, Stéphanie; Cura, Vincent; Stolfa, Diana A; Schmidtkunz, Karin; Lancelot, Julien; Andrade, Luiza; Renaud, Jean-Paul; Oliveira, Guilherme; Sippl, Wolfgang; Jung, Manfred; Cavarelli, Jean; Pierce, Raymond J; Romier, Christophe

    2013-01-01

    The treatment of schistosomiasis, a disease caused by blood flukes parasites of the Schistosoma genus, depends on the intensive use of a single drug, praziquantel, which increases the likelihood of the development of drug-resistant parasite strains and renders the search for new drugs a strategic priority. Currently, inhibitors of human epigenetic enzymes are actively investigated as novel anti-cancer drugs and have the potential to be used as new anti-parasitic agents. Here, we report that Schistosoma mansoni histone deacetylase 8 (smHDAC8), the most expressed class I HDAC isotype in this organism, is a functional acetyl-L-lysine deacetylase that plays an important role in parasite infectivity. The crystal structure of smHDAC8 shows that this enzyme adopts a canonical α/β HDAC fold, with specific solvent exposed loops corresponding to insertions in the schistosome HDAC8 sequence. Importantly, structures of smHDAC8 in complex with generic HDAC inhibitors revealed specific structural changes in the smHDAC8 active site that cannot be accommodated by human HDACs. Using a structure-based approach, we identified several small-molecule inhibitors that build on these specificities. These molecules exhibit an inhibitory effect on smHDAC8 but show reduced affinity for human HDACs. Crucially, we show that a newly identified smHDAC8 inhibitor has the capacity to induce apoptosis and mortality in schistosomes. Taken together, our biological and structural findings define the framework for the rational design of small-molecule inhibitors specifically interfering with schistosome epigenetic mechanisms, and further support an anti-parasitic epigenome targeting strategy to treat neglected diseases caused by eukaryotic pathogens.

  16. Structural Basis for the Inhibition of Histone Deacetylase 8 (HDAC8), a Key Epigenetic Player in the Blood Fluke Schistosoma mansoni

    PubMed Central

    Marek, Martin; Kannan, Srinivasaraghavan; Hauser, Alexander-Thomas; Moraes Mourão, Marina; Caby, Stéphanie; Cura, Vincent; Stolfa, Diana A.; Schmidtkunz, Karin; Lancelot, Julien; Andrade, Luiza; Renaud, Jean-Paul; Oliveira, Guilherme; Sippl, Wolfgang; Jung, Manfred; Cavarelli, Jean; Pierce, Raymond J.; Romier, Christophe

    2013-01-01

    The treatment of schistosomiasis, a disease caused by blood flukes parasites of the Schistosoma genus, depends on the intensive use of a single drug, praziquantel, which increases the likelihood of the development of drug-resistant parasite strains and renders the search for new drugs a strategic priority. Currently, inhibitors of human epigenetic enzymes are actively investigated as novel anti-cancer drugs and have the potential to be used as new anti-parasitic agents. Here, we report that Schistosoma mansoni histone deacetylase 8 (smHDAC8), the most expressed class I HDAC isotype in this organism, is a functional acetyl-L-lysine deacetylase that plays an important role in parasite infectivity. The crystal structure of smHDAC8 shows that this enzyme adopts a canonical α/β HDAC fold, with specific solvent exposed loops corresponding to insertions in the schistosome HDAC8 sequence. Importantly, structures of smHDAC8 in complex with generic HDAC inhibitors revealed specific structural changes in the smHDAC8 active site that cannot be accommodated by human HDACs. Using a structure-based approach, we identified several small-molecule inhibitors that build on these specificities. These molecules exhibit an inhibitory effect on smHDAC8 but show reduced affinity for human HDACs. Crucially, we show that a newly identified smHDAC8 inhibitor has the capacity to induce apoptosis and mortality in schistosomes. Taken together, our biological and structural findings define the framework for the rational design of small-molecule inhibitors specifically interfering with schistosome epigenetic mechanisms, and further support an anti-parasitic epigenome targeting strategy to treat neglected diseases caused by eukaryotic pathogens. PMID:24086136

  17. Immune reactivity in early life stages of sea-cage cultured Pacific bluefin tuna naturally infected with blood flukes from genus Cardicola (Trematoda: Aporocotylidae).

    PubMed

    Pennacchi, Ylenia; Shirakashi, Sho; Nowak, Barbara F; Bridle, Andrew R

    2016-11-01

    Pacific bluefin tuna (PBT), Thunnus orientalis, due to its high average price on the market is an economically valuable fish species. Infections by blood flukes from the genus Cardicola (Trematoda: Aporocotylidae) represent a growing concern for the cage culture of bluefin tuna in Japan, Australia and Southern Europe. The accumulation of numerous Cardicola eggs in the fish gills causes severe pathology that has been linked to mortality in PBT juveniles up to one year old. The only effective treatment used to mitigate the infection is the oral administration of the antihelminthic drug praziquantel (PZQ) to the affected fish. However, with the need to minimise therapeutic drug use in aquaculture it is hoped that immunoprophylaxis can provide a future alternative to protect the PBT juveniles against Cardicola infection. Currently, little is known of the host immune response to these parasites and of their infection dynamics. In this study, using real-time qPCR we aimed to quantitatively detect C. orientalis and C. opisthorchis DNA within the gills and heart of cultured PBT juveniles and to investigate the host immune response at the transcriptional level in the gills. The research focused mainly during early stages of infection soon after young PBT were transferred to culture cages (from 14 to 77 days post-transfer). An increase (up to 11-fold) of immune-related genes, namely IgM, MHC-I, TCR-β and IL-1β was observed in the PBT gills infected with Cardicola spp. (28-77 days post-transfer). Furthermore, IgM (19-fold increase) and MHC-I (11.5-fold increase) transcription was strongly up-regulated in gill samples of PBT infected with C. orientalis relative to uninfected fish but not in fish infected with C. opisthorchis. Cardicola-specific DNA was first detected in the host 14 days post-transfer (DPT) to sea-cages which was 55 days earlier than the first detection of parasite eggs and adults by microscopy. Oral administration of PZQ did not have an immediate effect

  18. The Sinbad retrotransposon from the genome of the human blood fluke, Schistosoma mansoni, and the distribution of related Pao-like elements.

    PubMed

    Copeland, Claudia S; Mann, Victoria H; Morales, Maria E; Kalinna, Bernd H; Brindley, Paul J

    2005-02-23

    Of the major families of long terminal repeat (LTR) retrotransposons, the Pao/BEL family is probably the least well studied. It is becoming apparent that numerous LTR retrotransposons and other mobile genetic elements have colonized the genome of the human blood fluke, Schistosoma mansoni. A proviral form of Sinbad, a new LTR retrotransposon, was identified in the genome of S. mansoni. Phylogenetic analysis indicated that Sinbad belongs to one of five discreet subfamilies of Pao/BEL like elements. BLAST searches of whole genomes and EST databases indicated that members of this clade occurred in species of the Insecta, Nematoda, Echinodermata and Chordata, as well as Platyhelminthes, but were absent from all plants, fungi and lower eukaryotes examined. Among the deuterostomes examined, only aquatic species harbored these types of elements. All four species of nematode examined were positive for Sinbad sequences, although among insect and vertebrate genomes, some were positive and some negative. The full length, consensus Sinbad retrotransposon was 6,287 bp long and was flanked at its 5'- and 3'-ends by identical LTRs of 386 bp. Sinbad displayed a triple Cys-His RNA binding motif characteristic of Gag of Pao/BEL-like elements, followed by the enzymatic domains of protease, reverse transcriptase (RT), RNAseH, and integrase, in that order. A phylogenetic tree of deduced RT sequences from 26 elements revealed that Sinbad was most closely related to an unnamed element from the zebrafish Danio rerio and to Saci-1, also from S. mansoni. It was also closely related to Pao from Bombyx mori and to Ninja of Drosophila simulans. Sinbad was only distantly related to the other schistosome LTR retrotransposons Boudicca, Gulliver, Saci-2, Saci-3, and Fugitive, which are gypsy-like. Southern hybridization and bioinformatics analyses indicated that there were about 50 copies of Sinbad in the S. mansoni genome. The presence of ESTs representing transcripts of Sinbad in numerous

  19. The Sinbad retrotransposon from the genome of the human blood fluke, Schistosoma mansoni, and the distribution of related Pao-like elements

    PubMed Central

    Copeland, Claudia S; Mann, Victoria H; Morales, Maria E; Kalinna, Bernd H; Brindley, Paul J

    2005-01-01

    Background Of the major families of long terminal repeat (LTR) retrotransposons, the Pao/BEL family is probably the least well studied. It is becoming apparent that numerous LTR retrotransposons and other mobile genetic elements have colonized the genome of the human blood fluke, Schistosoma mansoni. Results A proviral form of Sinbad, a new LTR retrotransposon, was identified in the genome of S. mansoni. Phylogenetic analysis indicated that Sinbad belongs to one of five discreet subfamilies of Pao/BEL like elements. BLAST searches of whole genomes and EST databases indicated that members of this clade occurred in species of the Insecta, Nematoda, Echinodermata and Chordata, as well as Platyhelminthes, but were absent from all plants, fungi and lower eukaryotes examined. Among the deuterostomes examined, only aquatic species harbored these types of elements. All four species of nematode examined were positive for Sinbad sequences, although among insect and vertebrate genomes, some were positive and some negative. The full length, consensus Sinbad retrotransposon was 6,287 bp long and was flanked at its 5'- and 3'-ends by identical LTRs of 386 bp. Sinbad displayed a triple Cys-His RNA binding motif characteristic of Gag of Pao/BEL-like elements, followed by the enzymatic domains of protease, reverse transcriptase (RT), RNAseH, and integrase, in that order. A phylogenetic tree of deduced RT sequences from 26 elements revealed that Sinbad was most closely related to an unnamed element from the zebrafish Danio rerio and to Saci-1, also from S. mansoni. It was also closely related to Pao from Bombyx mori and to Ninja of Drosophila simulans. Sinbad was only distantly related to the other schistosome LTR retrotransposons Boudicca, Gulliver, Saci-2, Saci-3, and Fugitive, which are gypsy-like. Southern hybridization and bioinformatics analyses indicated that there were about 50 copies of Sinbad in the S. mansoni genome. The presence of ESTs representing transcripts of Sinbad

  20. Unusual thiol-based redox metabolism of parasitic flukes.

    PubMed

    Tripathi, Timir; Suttiprapa, Sutas; Sripa, Banchob

    2016-05-27

    Parasitic flukes are exposed to free radicals and, to a greater extent, reactive oxygen species (ROS) during their life cycle. Despite being relentlessly exposed to ROS released by activated immune cells, these parasites can survive for many years in the host. Cellular thiol-based redox metabolism plays a crucial role in parasite survival within their hosts. Evidence shows that oxidative stress and redox homeostasis maintenance are important clinical and pathobiochemical as well as effective therapeutic principles in various diseases. The characterization of redox and antioxidant enzymes is likely to yield good target candidates for novel drugs and vaccines. The absence of active catalase in fluke parasites offers great potential for the development of chemotherapeutic agents that act by perturbing the redox equilibrium of the cell. One of the redox-sensitive enzymes, thioredoxin glutathione reductase (TGR), has been accepted as a drug target against blood fluke infections, and related clinical trials are in progress. TGR is the sole enzyme responsible for Trx and GSH reduction in parasitic flukes. The availability of helminth genomes has accelerated the research on redox metabolism of flukes; however, significant achievements have yet to be attained. The present review summarizes current knowledge on the redox and antioxidant system of the parasitic flukes.

  1. Calmodulin disruption impacts growth and motility in juvenile liver fluke.

    PubMed

    McCammick, Erin M; McVeigh, Paul; McCusker, Paul; Timson, David J; Morphew, Russell M; Brophy, Peter M; Marks, Nikki J; Mousley, Angela; Maule, Aaron G

    2016-01-27

    Deficiencies in effective flukicide options and growing issues with drug resistance make current strategies for liver fluke control unsustainable, thereby promoting the need to identify and validate new control targets in Fasciola spp. parasites. Calmodulins (CaMs) are small calcium-sensing proteins with ubiquitous expression in all eukaryotic organisms and generally use fluctuations in intracellular calcium levels to modulate cell signalling events. CaMs are essential for fundamental processes including the phosphorylation of protein kinases, gene transcription, calcium transport and smooth muscle contraction. In the blood fluke Schistosoma mansoni, calmodulins have been implicated in egg hatching, miracidial transformation and larval development. Previously, CaMs have been identified amongst liver fluke excretory-secretory products and three CaM-like proteins have been characterised biochemically from adult Fasciola hepatica, although their functions remain unknown. In this study, we set out to investigate the biological function and control target potential of F. hepatica CaMs (FhCaMs) using RNAi methodology alongside novel in vitro bioassays. Our results reveal that: (i) FhCaMs are widely expressed in parenchymal cells throughout the forebody region of juvenile fluke; (ii) significant transcriptional knockdown of FhCaM1-3 was inducible by exposure to either long (~200 nt) double stranded (ds) RNAs or 27 nt short interfering (si) RNAs, although siRNAs were less effective than long dsRNAs; (iii) transient long dsRNA exposure-induced RNA interference (RNAi) of FhCaMs triggered transcript knockdown that persisted for ≥ 21 days, and led to detectable suppression of FhCaM proteins; (iv) FhCaM RNAi significantly reduced the growth of juvenile flukes maintained in vitro; (v) FhCaM RNAi juveniles also displayed hyperactivity encompassing significantly increased migration; (vi) both the reduced growth and increased motility phenotypes were recapitulated in juvenile

  2. Blood flukes (Digenea: Aporocotylidae) of epipelagic lamniforms: redescription of Hyperandrotrema cetorhini from basking shark (Cetorhinus maximus) and description of a new congener from shortfin mako shark (Isurus oxyrinchus) off Alabama.

    PubMed

    Orélis-Ribeiro, Raphael; Ruiz, Carlos F; Curran, Stephen S; Bullard, Stephen A

    2013-10-01

    We emend the original generic diagnosis for Hyperandrotrema Maillard and Ktari, 1978 , and redescribe its type species Hyperandrotrema cetorhini Maillard and Ktari, 1978 (Digenea: Aporocotylidae Odhner, 1912), based on the holotype and 2 paratypes collected from the heart of basking shark (Cetorhinus maximus). We also describe Hyperandrotrema walterboegeri Orélis-Ribeiro and Bullard n. sp. based on light and scanning electron microscopy of 6 adult specimens collected from the heart of a shortfin mako shark (Isurus oxyrinchus Rafinesque, 1810) captured from Viosca Knoll (29°11.70'N, 88°33.32'W; 123 km southwest of Dauphin Island, Alabama), northern Gulf of Mexico. Hyperandrotrema spp. infect lamniforms and differ from all other nominal aporocotylids at least by having a ventrolateral field of robust C-shaped spines (rather than transverse rows of minute, shaft-like spines), an inverse U-shaped intestine with extremely elongate ceca terminating near the level of the excretory bladder, and a common genital pore that comprises the dorsal opening of a common genital atrium. Adults of the new species exceeded 12 mm in total length, making them the largest of the nominal fish blood flukes. The new species further differs from H. cetorhini by the combination of having an adult body that is 7-8 times longer than wide, large midbody tegumental spines measuring 25-38 μm long × 10-12 μm wide, a long vas deferens 4-5% of the body length, a testis 9-11 times longer than wide, and a large ootype 105-150 μm long × 85-105 μm wide. This is the first report of Hyperandrotrema from the Gulf of Mexico and the second aporocotylid species reported from an epipelagic elasmobranch. Our results demonstrate that ecologically related (epipelagic, marine) and phylogenetically related (Lamniformes) definitive hosts are infected by morphologically similar (congeneric) fish blood flukes.

  3. Liver Fluke-Associated Biliary Tract Cancer.

    PubMed

    Prueksapanich, Piyapan; Piyachaturawat, Panida; Aumpansub, Prapimphan; Ridtitid, Wiriyaporn; Chaiteerakij, Roongruedee; Rerknimitr, Rungsun

    2017-08-09

    Cholangiocarcinoma (CCA) is an aggressive cancer arising from epithelial cells of the bile duct. Most patients with CCA have an unresectable tumor at the time of diagnosis. In Western countries, the risk of CCA increases in patients with primary sclerosing cholangitis, whereas liver fluke infection appears to be the major risk factor for CCA in Asian countries. A diagnosis of liver fluke infection often relies on stool samples, including microscopic examination, polymerase chain reaction-based assays, and fluke antigen detection. Tests of serum, saliva and urine samples are also potentially diagnostic. The presence of liver fluke along with exogenous carcinogens magnifies the risk of CCA in people living in endemic areas. The "liver fluke-cholangiocarcinoma" carcinogenesis pathways consist of mechanical damage to the bile duct epithelium, immunopathologic and cellular reactions to the liver fluke's antigens and excretory/secretory products, liver fluke-induced changes in the biliary tract microbiome and the effects of repeated treatment for liver fluke. A vaccine and novel biomarkers are needed for the primary and secondary prevention of CCA in endemic areas. Importantly, climate change exerts an effect on vector-borne parasitic diseases, and awareness of liver fluke should be enhanced in potentially migrated habitat areas.

  4. Identification of the rumen fluke, Calicophoron daubneyi, in GB livestock: possible implications for liver fluke diagnosis.

    PubMed

    Gordon, D K; Roberts, L C P; Lean, N; Zadoks, R N; Sargison, N D; Skuce, P J

    2013-07-01

    The liver fluke, Fasciola hepatica, is common in many parts of Great Britain. To detect liver fluke infection and to assess whether fasciolicide treatment has been successful, the faecal egg count (FEC) and faecal egg count reduction test (FECRT) are widely used. Rumen fluke is also increasingly reported from Great Britain, but its species identity is yet to be determined. Liver fluke and rumen fluke eggs are morphologically similar, which may lead to erroneous diagnoses of liver fluke infection or treatment failure. As an alternative to FEC, a coproantigen ELISA (cELISA) can be used. The potential for this test to cross-react with rumen fluke species from Great Britain has not been evaluated. Rumen fluke specimens from cattle and sheep in Scotland were identified to species level using DNA sequencing of the ITS-2 region. Subsequently, rumen and liver fluke obtained from naturally co-infected sheep were subjected to immunohistochemistry using antibodies from a commercially available cELISA kit for F. hepatica. Finally, faecal samples from naturally co-infected sheep flocks were examined by FEC and cELISA. Rumen fluke from imported and home-bred cattle and sheep in Scotland belonged to the species Calicophoron daubneyi, rather than Paramphistomum cervi, the species presumed to be most common in Great Britain. Intense staining of the gastrodermis was observed in F. hepatica but cross-reactivity with C. daubneyi was not seen. Faecal samples that contained rumen fluke eggs but not liver fluke eggs were all negative by cELISA. We conclude that C. daubneyi is the most common rumen fluke of domestic ruminants in Scotland and that cELISA reduction testing may be a valuable alternative to FECRT in herds or flocks that are co-infected with liver and rumen fluke. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Chromosomes of the liver fluke, Clonorchis sinensis

    PubMed Central

    Park, Gab-Man; Im, Kyung-il; Huh, Sun

    2000-01-01

    A karyological study was carried out in order to compared the chromosome numbers, chromosome morphologies and karyotypes of the oriental liver fluke, Clonorchis sinensis (Trematoda: Opisthorchiidae), collected from Korea and China. Chromosome preparations were made by means of air-drying method. The chromosome number was 2n=56 in both Korean and Chinese flukes, and chromosomes were divided into two groups based on this size; consisting of 8 pairs of large and 20 pairs of small chromosomes. However, the karyotypes showed some differences between Korean and Chinese flukes. The karyotype of liver flukes from Korea consisted of three metacentric pairs, one meta-/submetacentric pair, 16 submetacentric pairs and eight subtelocentric pairs of chromosomes. On the other hand, liver flukes from China consisted of two metacentric pairs, two meta-/submetacentric pairs, 16 submetacentric pairs and eight subtelocentric pairs of chromosomes. PMID:11002660

  6. In silico analysis of the fucosylation-associated genome of the human blood fluke Schistosoma mansoni: cloning and characterization of the enzymes involved in GDP-L-fucose synthesis and Golgi import

    PubMed Central

    2013-01-01

    Background Carbohydrate structures of surface-expressed and secreted/excreted glycoconjugates of the human blood fluke Schistosoma mansoni are key determinants that mediate host-parasite interactions in both snail and mammalian hosts. Fucose is a major constituent of these immunologically important glycans, and recent studies have sought to characterize fucosylation-associated enzymes, including the Golgi-localized fucosyltransferases that catalyze the transfer of L-fucose from a GDP-L-fucose donor to an oligosaccharide acceptor. Importantly, GDP-L-fucose is the only nucleotide-sugar donor used by fucosyltransferases and its availability represents a bottleneck in fucosyl-glycotope expression. Methods A homology-based genome-wide bioinformatics approach was used to identify and molecularly characterize the enzymes that contribute to GDP-L-fucose synthesis and Golgi import in S. mansoni. Putative functions were further investigated through molecular phylogenetic and immunocytochemical analyses. Results We identified homologs of GDP-D-mannose-4,6-dehydratase (GMD) and GDP-4-keto-6-deoxy-D-mannose-3,5-epimerase-4-reductase (GMER), which constitute a de novo pathway for GDP-L-fucose synthesis, in addition to a GDP-L-fucose transporter (GFT) that putatively imports cytosolic GDP-L-fucose into the Golgi. In silico primary sequence analyses identified characteristic Rossman loop and short-chain dehydrogenase/reductase motifs in GMD and GMER as well as 10 transmembrane domains in GFT. All genes are alternatively spliced, generating variants of unknown function. Observed quantitative differences in steady-state transcript levels between miracidia and primary sporocysts may contribute to differential glycotope expression in early larval development. Additionally, analyses of protein expression suggest the occurrence of cytosolic GMD and GMER in the ciliated epidermal plates and tegument of miracidia and primary sporocysts, respectively, which is consistent with previous

  7. In silico analysis of the fucosylation-associated genome of the human blood fluke Schistosoma mansoni: cloning and characterization of the enzymes involved in GDP-L-fucose synthesis and Golgi import.

    PubMed

    Peterson, Nathan A; Anderson, Tavis K; Wu, Xiao-Jun; Yoshino, Timothy P

    2013-07-09

    Carbohydrate structures of surface-expressed and secreted/excreted glycoconjugates of the human blood fluke Schistosoma mansoni are key determinants that mediate host-parasite interactions in both snail and mammalian hosts. Fucose is a major constituent of these immunologically important glycans, and recent studies have sought to characterize fucosylation-associated enzymes, including the Golgi-localized fucosyltransferases that catalyze the transfer of L-fucose from a GDP-L-fucose donor to an oligosaccharide acceptor. Importantly, GDP-L-fucose is the only nucleotide-sugar donor used by fucosyltransferases and its availability represents a bottleneck in fucosyl-glycotope expression. A homology-based genome-wide bioinformatics approach was used to identify and molecularly characterize the enzymes that contribute to GDP-L-fucose synthesis and Golgi import in S. mansoni. Putative functions were further investigated through molecular phylogenetic and immunocytochemical analyses. We identified homologs of GDP-D-mannose-4,6-dehydratase (GMD) and GDP-4-keto-6-deoxy-D-mannose-3,5-epimerase-4-reductase (GMER), which constitute a de novo pathway for GDP-L-fucose synthesis, in addition to a GDP-L-fucose transporter (GFT) that putatively imports cytosolic GDP-L-fucose into the Golgi. In silico primary sequence analyses identified characteristic Rossman loop and short-chain dehydrogenase/reductase motifs in GMD and GMER as well as 10 transmembrane domains in GFT. All genes are alternatively spliced, generating variants of unknown function. Observed quantitative differences in steady-state transcript levels between miracidia and primary sporocysts may contribute to differential glycotope expression in early larval development. Additionally, analyses of protein expression suggest the occurrence of cytosolic GMD and GMER in the ciliated epidermal plates and tegument of miracidia and primary sporocysts, respectively, which is consistent with previous localization of highly

  8. Liver fluke isolates: a question of provenance.

    PubMed

    Fairweather, I

    2011-02-28

    A survey of literature on experimental infections with the liver fluke, Fasciola hepatica published between 2005 and 2009 has revealed a general lack of information on where fluke material (i.e. metacercariae) was sourced from. Even less information was given on the drug status of the fluke isolate used, which is a particular concern for those studies that involved anthelmintics. In these two respects, information on the liver fluke lags far behind that for nematodes, where such information is given almost as a matter of course. Of additional concern is that, at times, information about the source and drug history of fluke isolates was incorrect. The overall aim of the review is to demonstrate why it is important to provide as much information as possible on what fluke material is being used. It also attempts to correct some of the errors in the literature and gather together what information is available about the provenance of those isolates that have been used in recent experimental studies. Copyright © 2010 Elsevier B.V. All rights reserved.

  9. Identity of rumen fluke in deer.

    PubMed

    O'Toole, Ailis; Browne, John A; Hogan, Sean; Bassière, Thomas; DeWaal, Theo; Mulcahy, Grace; Zintl, Annetta

    2014-11-01

    As evidence is growing that in many temperate areas paramphistome infections are becoming more common and widespread, this study was undertaken to determine the role of deer as reservoirs for rumen fluke infections in livestock. A total of 144 deer faecal samples (88 from fallow deer, 32 from red deer and 24 samples from sika, sika/red deer hybrids) were screened for the presence of fluke eggs. Based on the ITS-2 rDNA locus plus flanking 5.8S and 28S sequences (ITS-2+), fluke eggs were identified to species level. Our results indicate that, of the 3 deer species, fallow deer had the highest fluke infection rates. Two rumen fluke species, Calicophoron daubneyi and Paramphistomum leydeni, with morphologically distinct eggs, were identified. Concurrent infections of the two paramphistome species and liver fluke, Fasciola hepatica, were common. Considering the comparatively low egg burdens observed in this study, it is unlikely that deer represent a significant source of infection for Irish livestock.

  10. Liver fluke vaccines in ruminants: strategies, progress and future opportunities.

    PubMed

    Toet, Hayley; Piedrafita, David M; Spithill, Terry W

    2014-10-15

    The development of a vaccine for Fasciola spp. in livestock is a challenge and would be advanced by harnessing our knowledge of acquired immune mechanisms expressed by resistant livestock against fluke infection. Antibody-dependent cell-mediated cytotoxicity directed to the surface tegument of juvenile/immature flukes is a host immune effector mechanism, suggesting that antigens on the surface of young flukes may represent prime candidates for a fluke vaccine. A Type 1 immune response shortly after fluke infection is associated with resistance to infection in resistant sheep, indicating that vaccine formulations should attempt to induce Type 1 responses to enhance vaccine efficacy. In cattle or sheep, an optimal fluke vaccine would need to reduce mean fluke burdens in a herd below the threshold of 30-54 flukes to ensure sustainable production benefits. Fluke infection intensity data suggest that vaccine efficacy of approximately 80% is required to reduce fluke burdens below this threshold in most countries. With the increased global prevalence of triclabendazole-resistant Fasciolahepatica, it may be commercially feasible in the short term to introduce a fluke vaccine of reasonable efficacy that will provide economic benefits for producers in regions where chemical control of new drug-resistant fluke infections is not viable. Commercial partnerships will be needed to fast-track new candidate vaccines using acceptable adjuvants in relevant production animals, obviating the need to evaluate vaccine antigens in rodent models. Copyright © 2014 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

  11. Prevalence of liver fluke infection in Irish horses and assessment of a serological test for diagnosis of equine fasciolosis.

    PubMed

    Quigley, A; Sekiya, M; Egan, S; Wolfe, A; Negredo, C; Mulcahy, G

    2017-03-01

    There is little information on the prevalence of Fasciola hepatica infection in the horse population in Ireland or the potential impact of fluke infection on animal health. To investigate F. hepatica infection in the Irish horse population and to assess the diagnostic potential of an indirect enzyme-linked immunosorbent assay (ELISA) based on the F. hepatica recombinant cathepsin L1 (CL1) antigen. Cross-sectional abattoir survey of horses for liver fluke status. Animals (n = 200) were examined at an abattoir between May 2013 and April 2014. Horses were graded ante mortem for body condition score. Blood and faeces were collected and livers were examined post mortem by gross morphology. A cohort (n = 35) of livers were also examined histologically. Haematology and blood biochemistry, including serum liver enzyme activities, were measured and faeces were sedimented for egg counts. Serum was assayed by indirect ELISA using a recombinant CL1. The prevalence of liver fluke infection was 9.5%. There was no correlation between liver fluke status and time of year, breed classification, age group, sex, body condition score, ante mortem assessment, strongyle infection status, serum liver enzyme activities or CL1 concentration. A comparison of the CL1 ELISA in horse sera compared with a reference standard diagnosis showed high specificity of 95.6% (95% confidence interval [CI] 91.5-98.0%), but low sensitivity of 42.1% (95% CI 20.2-66.5%). This study is limited by its nature as an abattoir study, the relatively small number of animals examined (n = 200), and the absence of a known negative group of horses. Blood biomarkers are not good indicators of liver fluke infection and the CL1 ELISA is not a sensitive tool for diagnosis of fluke infection in the horse. The prevalence of F. hepatica in horses indicates that further research is required to assess the potential impact of liver fluke on equine liver health. © 2016 EVJ Ltd.

  12. Is Opisthorchis viverrini an avian liver fluke?

    PubMed

    Nawa, Y; Doanh, P N; Thaenkham, U

    2015-03-01

    Recently, in the Journal of Helminthology (May 2013), Dao et al. reported that Opisthorchis viverrini-like flukes were found in the bile duct of domestic ducks in Vietnam. They stated that this is the first record of Opisthorchis sp. in birds in Vietnam. However, three Opisthorchis species--O. cheelis, O. longissimus and O. parageminus--in birds in Vietnam were described by Le in 2000. Amongst these, O. parageminus was first reported, by Oshmarin in 1970, as a new Opisthorchis species found in domestic ducks (Anas platyrhynchos) in Vietnam. Morphologially O. viverrini-like flukes described by Dao et al. are much more similar to O. parageminus than to O. viverrini. The phylogenetic trees of internal transcribed spacer 2 (ITS2) and cytochrome oxidase 1 (CO1) gene sequences also showed that the O. viverrini-like liver flukes from domestic ducks were closer to O. lobatus than to O. viverrini. Therefore, O. viverrini-like liver flukes reported by Dao et al. (2013) are most likely to be O. parageminus.

  13. Diversity and ancestry of flatworms infecting blood of nontetrapod craniates "fishes".

    PubMed

    Orélis-Ribeiro, Raphael; Arias, Cova R; Halanych, Kenneth M; Cribb, Thomas H; Bullard, Stephen A

    2014-01-01

    We herein review all published molecular studies (life history, taxonomy, and phylogeny) and summarize all GenBank sequences and primer sets for the "fish blood flukes". Further, by analysing new and all available sequence data for the partial D1-D2 domains of 28S from 83 blood fluke taxa, we explore the evolutionary expansion of flatworm parasitism in the blood of craniates. Based on this analysis, the blood flukes infecting marine bony fishes (Euteleostei) are monophyletic. The clade comprising the chondrichthyan blood fluke plus the marine euteleost blood flukes is the sister group to tetrapod blood flukes (spirorchiids and schistosomes). The innominate blood fluke cercariae from freshwater gastropods were monophyletic and sister to the clade comprising spirorchiids and schistosomes, but low nodal support indicated that they may represent a distinct blood fluke lineage with phylogenetic affinities also to fish blood flukes. Blood flukes that utilize gastropod intermediate hosts were monophyletic (unidentified gastropod cercariae+tetrapod blood flukes) and those utilizing bivalves and polychaetes were monophyletic (marine fish blood flukes). Low or no taxon sampling among blood flukes of basal fish lineages and primary division freshwater fish lineages are significant data gaps needing closure. We also note that no record of an infection exists in a hagfish (Myxiniformes), lamprey (Petromyzontiformes), or nontetrapod sarcopterygiian, i.e., coelacanth (Coelacanthimorpha) or lungfish (Dipnoi). The present phylogenetic analysis reiterated support for monophyly of Schistosomatidae and paraphyly of spirorchiids, with the blood flukes of freshwater turtles basal to those of marine turtles and schistosomes. © 2014 Elsevier Ltd All rights reserved.

  14. Quality and exploitation of umbilical cord blood for cell therapy: Are we beyond our capabilities?

    PubMed

    Roura, Santiago; Pujal, Josep Maria; Gálvez-Montón, Carolina; Bayes-Genis, Antoni

    2016-07-01

    There is increasing interest in identifying novel stem cell sources for application in emerging cell therapies. In this context, umbilical cord blood (UCB) shows great promise in multiple clinical settings. The number of UCB banks has therefore increased worldwide, with the objective of preserving potentially life-saving cells that are usually discarded after birth. After a rather long and costly processing procedure, the resultant UCB-derived cell products are cryopreserved until transplantation to patients. However, in many cases, only a small proportion of administered cells engraft successfully. Thus, can we do any better regarding current UCB-based therapeutic approaches? Here we discuss concerns about the use of UCB that are not critically pondered by researchers, clinicians, and banking services, including wasting samples with small volumes and the need for more reliable quality and functional controls to ensure the biological activity of stem cells and subsequent engraftment and treatment efficacy. Finally, we appeal for collaborative agreements between research institutions and UCB banks in order to redirect currently discarded small-volume UCB units for basic and clinical research purposes. Developmental Dynamics 245:710-717, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  15. Paragonimus kellicotti flukes in Missouri, USA.

    PubMed

    Lane, Michael A; Marcos, Luis A; Onen, Nur F; Demertzis, Lee M; Hayes, Ericka V; Davila, Samuel Z; Nurutdinova, Diana R; Bailey, Thomas C; Weil, Gary J

    2012-08-01

    Paragonimiasis is an infection caused by lung flukes of the genus Paragonimus. In Asia, P. westermani infections are relatively common because of dietary practices. However, in North America, cases of paragonimiasis, which are caused by P. kellicotti flukes, are rare. Only 7 autochthonous cases of paragonimiasis were reported during 1968-2008. In 2009, we reported 3 new case-patients with paragonimiasis who had been seen at our medical center over an 18-month period. Six additional case-patients were identified in St. Louis, Missouri, USA, and treated at Washington University-affiliated health centers in 2009-2010. We report detailed descriptions of these case-patients, which includes unusual clinical manifestations. We also describe public health interventions that were undertaken to inform the general public and physicians about the disease and its mode of transmission.

  16. Opisthorchis viverrini: The carcinogenic human liver fluke

    PubMed Central

    Kaewpitoon, Natthawut; Kaewpitoon, Soraya J; Pengsaa, Prasit; Sripa, Banchob

    2008-01-01

    Opisthorchiasis caused by Opisthorchis viverrini remains a major public health problem in many parts of Southeast Asia, including Thailand, Lao PDR, Vietnam and Cambodia. The infection is associated with a number of hepatobiliary diseases, including cholangitis, obstructive jaundice, hepatomegaly, cholecystitis and cholelithiasis. Multi-factorial etiology of cholangiocarcinoma, mechanical damage, parasite secretions, and immunopathology may enhance cholangiocarcinogenesis. Moreover, both experimental and epidemiological evidences strongly implicate liver fluke infection as the major risk factor in cholangiocarcinoma, cancer of the bile ducts. The liver fluke infection is induced by eating raw or uncooked fish products that is the tradition and popular in the northeastern and northern region, particularly in rural areas, of Thailand. The health education programs to prevent and control opisthorchiasis are still required in the high-risk areas. PMID:18205254

  17. Blood flukes (Digenea: Aporocotylidae) of elopomorphs: emendation of Paracardicoloides, supplemental observations of Paracardicoloides yamagutii, and a new genus and species from ladyfish, Elops saurus, (Elopiformes: Elopidae) in the Gulf of Mexico.

    PubMed

    Bullard, Stephen A

    2014-06-01

    Monotypic Paracardicoloides Martin, 1974 is emended based on supplemental observations of 2 voucher specimens of Paracardicoloides yamagutii Martin, 1974 . Features of the anterior sucker, esophagus, and intestine as well as the male and female genitalia previously attributed to, or omitted from the diagnosis and description of, this fluke are resolved and further detailed herein. The holotype of P. yamagutii, originally deposited in the Allan Hancock Parasitology Collection, apparently has been lost, and Queensland Museum voucher G222650 is designated as the neotype. Elopicola nolancribbi n. gen., n. sp. infects the ladyfish, Elops saurus , (Elopiformes: Elopidae) in the north-central Gulf of Mexico. The new genus resembles Paracardicoloides by having the combination of a bowl-shaped anterior sucker, inverse U-shaped intestine, short posterior ceca, post-cecal ovary, pre-ovarian ootype, compact uterus, and prominent excretory arms and vesicle. It differs from Paracardicoloides by lacking robust tegumental body spines and by having a single testis, post-testicular ovary, and primarily post-testicular uterus. The present study is the first confirmed report of an aporocotylid infecting a member of Elopiformes as well as the first report of an infection in an elopomorph outside of Australia and New Zealand or in marine waters.

  18. Foodborne Intestinal Flukes in Southeast Asia

    PubMed Central

    Shin, Eun-Hee; Lee, Soon-Hyung; Rim, Han-Jong

    2009-01-01

    In Southeast Asia, a total of 59 species of foodborne intestinal flukes have been known to occur in humans. The largest group is the family Heterophyidae, which constitutes 22 species belonging to 9 genera (Centrocestus, Haplorchis, Heterophyes, Heterophyopsis, Metagonimus, Procerovum, Pygidiopsis, Stellantchasmus, and Stictodora). The next is the family Echinostomatidae, which includes 20 species in 8 genera (Artyfechinostomum, Acanthoparyphium, Echinochasmus, Echinoparyphium, Echinostoma, Episthmium, Euparyphium, and Hypoderaeum). The family Plagiorchiidae follows the next containing 5 species in 1 genus (Plagiorchis). The family Lecithodendriidae includes 3 species in 2 genera (Phaneropsolus and Prosthodendrium). In 9 other families, 1 species in 1 genus each is involved; Cathaemaciidae (Cathaemacia), Fasciolidae (Fasciolopsis), Gastrodiscidae (Gastrodiscoides), Gymnophallidae (Gymnophalloides), Microphallidae (Spelotrema), Neodiplostomidae (Neodiplostomum), Paramphistomatidae (Fischoederius), Psilostomidae (Psilorchis), and Strigeidae (Cotylurus). Various types of foods are sources of human infections. They include freshwater fish, brackish water fish, fresh water snails, brackish water snails (including the oyster), amphibians, terrestrial snakes, aquatic insects, and aquatic plants. The reservoir hosts include various species of mammals or birds.The host-parasite relationships have been studied in Metagonimus yokogawai, Echinostoma hortense, Fasciolopsis buski, Neodiplostomum seoulense, and Gymnophalloides seoi; however, the pathogenicity of each parasite species and host mucosal defense mechanisms are yet poorly understood. Clinical aspects of each parasite infection need more clarification. Differential diagnosis by fecal examination is difficult because of morphological similarity of eggs. Praziquantel is effective for most intestinal fluke infections. Continued efforts to understand epidemiological significance of intestinal fluke infections, with

  19. Progress in development of liver fluke vaccines.

    PubMed

    Spithill, T W; Dalton, J P

    1998-12-01

    Infection of ruminants by Fasciola spp continues to cause large economic losses worldwide. Recent results from several laboratories have demonstrated that animals can be significantly protected against infection by vaccination with defined Fasciola antigens. Apart from reducing fluke burdens, some vaccines can elicit a concurrent reduction in parasite egg production. The expectation of a commercially feasible vaccine that might also reduce parasite transmission in the field is now realistic, although major hurdles still exist. Here, Terry Spithill and John Dalton review the results of several recent vaccine trials and discuss the future prospects for vaccine development.

  20. Development of Experimental Vaccines Against Liver Flukes.

    PubMed

    Yap, Huan Yong; Smooker, Peter M

    2016-01-01

    A multitude of experimental vaccines have been developed against liver flukes in the past. However, there has yet to be the development of a commercial livestock vaccine. Reasons for this may be multiple, and include the lack of identification of the best antigen(s), or the immune response induced by those antigens not being appropriate in either magnitude or polarity (and therefore not protective). Cathepsin proteases are the major component of the excretory/secretory (ES) material of liver flukes in all stages of their life cycle in the definitive host and are the primary antigens of interest for the vaccine development in many studies. Hence, this chapter presents the methodologies of using cathepsin proteases as targeted antigens in recombinant protein and DNA vaccine development to engender protective immune responses against fasciolosis.First, the experimental vaccines developed in the past and the criteria of an effective vaccine for fasciolosis are briefly reviewed. Then flowcharts for recombinant protein vaccine and DNA vaccine development are presented, followed by the detailed materials and methodologies.

  1. Molecular phylogenetic identification of Fasciola flukes in Nepal.

    PubMed

    Shoriki, Takuya; Ichikawa-Seki, Madoka; Devkota, Bhuminand; Rana, Hari B; Devkota, Shiva P; Humagain, Sudeep K; Itagaki, Tadashi

    2014-12-01

    Eighty-one Fasciola flukes collected from 8 districts in Nepal were analyzed for their species identification on the basis of their spermatogenic status and nuclear ribosomal internal transcribed spacer 1 (ITS1) and for their phylogenetic relation with Fasciola flukes from other Asian countries on the basis of the mitochondrial NADH dehydrogenase subunit 1 (nad1) gene. Sixty-one flukes (75.3%) were aspermic Fasciola sp., and 20 flukes (24.7%) were identified as Fasciola gigantica. All of the aspermic flukes displayed the Fh/Fg type in ITS1, which was predominant in aspermic Fasciola sp. from China, and most (60 flukes) displayed the Fsp-ND1-N1 haplotype in the nad1, which had an identical nucleotide sequence to the major haplotype (Fg-C2) of the aspermic flukes from China. These results suggest that aspermic Fasciola sp. was introduced into Nepal from China. Furthermore, the results of the diversity indices, neutrality indices, and median-joining network analysis with reference haplotypes from Asian countries suggest that aspermic Fasciola sp. rapidly expanded its distribution. In contrasts, F. gigantica displayed 10 nad1 haplotypes, which showed higher population diversity indices than the haplotypes of aspermic flukes, indicating that the F. gigantica population was clearly distributed in Nepal earlier than the aspermic Fasciola population. Although the F. gigantica haplotypes from Nepal formed a star-like phylogeny consisting of a main founder haplotype (Fg-ND1-N1), together with some F. gigantica haplotypes from Myanmar and Thailand, the Nepal population differed genetically from F. gigantica populations of neighboring countries as each country had distinct founder haplotype(s).

  2. Human consumption of rumen flukes of cattle in India.

    PubMed

    Sarmah, P C; Laha, R; Bhattacharjee, K; Goswami, A; Raquib, M; Kakati, P

    2014-01-01

    The practice of eating rumen flukes of cattle by a section of people living in Meghalaya, a north eastern State of India, is reported in this communication. Economically backward, some rural people belonging to Khasi, Jaintia, Garo, and Karbi tribes of Christian and Nepali communities who eat beef are accustomed to consuming cooked flukes during breakfast, meals, and also along with rice beer or alcohol. Inspection of the rumens of cattle during slaughter indicated a prevalence of flukes belonging to Cotylophoron, Paramphistomum, Calicophoron, Gastrothylax, and Fischoederius genera in 74% cases, and their collection from rumen ranged approximately from 50 g to 600 g. Biochemical analysis of flukes found 12.60% total protein, 0.78% fat, and 0.87% ash on fresh weight basis. High prevalence of flukes, easy visualization in rumen, their bulk collection, presence of nutritive value, absence of any ill effect, and lack of imminent danger of transmissibility are believed to be the rationales influencing their consumption by people. It is suggested that dietary benefits obtained from flukes might contribute to the energy transfer and inclusion in the food web.

  3. Two new species of Elopicola (Digenea: Aporocotylidae) from Hawaiian ladyfish, Elops hawaiensis (Eastern Sea) and Atlantic tarpon, Megalops atlanticus (Gulf of Mexico) with a comment on monophyly of elopomorph blood flukes.

    PubMed

    Orélis-Ribeiro, Raphael; Halanych, Kenneth M; Dang, Binh T; Bakenhaster, Micah D; Arias, Cova R; Bullard, Stephen A

    2017-06-01

    Elopicola bristowi sp. n. infects the blood vascular system of Hawaiian ladyfish, Elops hawaiensis, in the Eastern Sea. It differs from the only nominal congener Elopicola nolancribbi by the combination of having rows of ventrolateral tegumental spines, a proportionally long oesophagus, anterior caeca, vasa efferentia coalescing ventral to the posterodextral margin of the testis, a post-testicular metraterm, a dextral common genital pore lateral to the oötype, and genitalia that are enantiomorphic relative to those of E. nolancribbi. Elopicola franksi sp. n. infects the heart and blood vascular system of Atlantic tarpon, Megalops atlanticus, in the Gulf of Mexico. It differs from its congeners by the combination of lacking ventrolateral tegumental spines and having an elongate body (6× longer than wide), a proportionally long oesophagus, a compact testis at level of the distal ends of the posterior caeca, and a post-testicular common genital pore at level of the oötype. Phylogenetic analyses based on the small subunit ribosomal DNA (18S), large subunit ribosomal DNA (28S), and internal transcribed spacer 2 (ITS2) genes revealed considerable genetic differences between these taxa. The 18S+28S tree showed a monophyletic Elopicola sister to all aporocotylids infecting fishes of Euteleosteomorpha. The ITS2 tree showed Paracardicoloides yamagutii as the sister taxon to Elopicola spp.

  4. Liver flukes promote cholelithiasis in sheep.

    PubMed

    Katsoulos, Panagiotis D; Christodoulopoulos, Georgios; Karatzia, Maria A; Pourliotis, Konstantinos; Minas, Anastasios

    2011-06-30

    The main objective of this study was to investigate whether cholelithiasis in sheep is related to parasitism or other commonly observed disorders such as liver abscesses. Additionally, the features of the observed biliary calculi are described. The livers of 254 randomly selected clinically healthy adult dairy sheep were used. All visible concretions in the bile were considered as stones. Based on the macroscopical examination, 60 livers were normal, 40 were parasitized with Fasciola hepatica, 42 were parasitized with Dicrocoelium dendriticum, 28 were parasitized with both D. dendriticum and F. hepatica, 40 livers had abscesses and 44 had hydatid cysts. Biliary calculi were detected in 40 livers. Twenty livers had pigment stones and 20 livers had cholesterol stones. The percentage of cholelithiasis was significantly higher in livers parasitized with flukes compared with the others (P<0.05) and the parasitoses with F. hepatica and D. dendriticum were proven to be significant risk factors (P<0.05) for the presence of cholelithiasis in sheep. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Molecular phylogenetic analysis of Fasciola flukes from eastern India.

    PubMed

    Hayashi, Kei; Ichikawa-Seki, Madoka; Mohanta, Uday Kumar; Singh, T Shantikumar; Shoriki, Takuya; Sugiyama, Hiromu; Itagaki, Tadashi

    2015-10-01

    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. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  6. Noninvasive assessment of liver stiffness by transient elastography (FibroScan) in liver fluke disease.

    PubMed

    Gao, Qiang; Shao, Dan; Pan, Aizhen; Gao, Mingyong; Liu, Zaiyi; Liang, Changhong

    2016-01-01

    Transient elastography is a noninvasive and reliable method for the assessment of liver stiffness. This study aimed to assess liver stiffness of asymptomatic liver fluke disease patients by FibroScan and evaluate the factors influencing liver stiffness. Overall, 65 patients were prospectively recruited from The First People's Hospital of Foshan, Guangdong, China. All patients were diagnosed with liver fluke disease; their durations of ingested freshwater raw fish or shrimp were more than 10 years, and none of them had abnormal liver function and hepatitis B virus or hepatitis C virus infection, or clinical symptoms. All patients underwent FibroScan, blood biochemical examination, and BMI measurement on the same day. Liver stiffness measurement (LSM) values, sex, age, durations of ingested freshwater raw fish or shrimp, and BMI were recorded. LSM value greater than 7.4 kPa was defined as abnormal. A total of 27 patients (41.5%) had abnormal LSM values. On partial correlation analysis, duration of ingested freshwater raw fish or shrimp was the independent factor that showed a positive correlation with abnormal LSM values (r=0.502, P=0.012). An independent-samples t-test showed that the durations of patients with abnormal LSM values were significantly longer than the durations of patients with normal LSM values (P<0.001). Sex, age, and BMI were not significantly correlated with LSM values (P>0.05). A high proportion of asymptomatic liver fluke disease patients had abnormal LSM values. The durations of patients with abnormal LSM values were significantly longer than the durations of patients with normal LSM values and the durations of patients with abnormal LSM values were an independent factor that showed a positive correlation with abnormal LSM values.

  7. The liver fluke Opisthorchis felineus: biology, epidemiology and carcinogenic potential.

    PubMed

    Pakharukova, Mariya Y; Mordvinov, Viatcheslav A

    2016-01-01

    The liver fluke Opisthorchis felineus is a member of the triad of epidemiologically important liver fluke species belonging to the family Opisthorchiidae and the major agent causing opisthorchiasis over a vast territory, covering Russia, Kazakhstan and several European countries. The similarity between the diseases caused by O. felineus and other liver flukes, O. viverrini and Clonorchis sinensis, in clinical manifestations and course suggests that the scenarios of their development and, possibly, complications have much in common. The International Agency for Research on Cancer classified O. viverrini and C. sinensis as group 1 agents and the major factors inducing cholangiocarcinoma in endemic regions. However, a carcinogenic potential of O. felineus is poorly studied. This review characterizes O. felineus, briefs the epidemiological situation in Western Siberia, the world's largest opisthorchiasis focus, and assesses the carcinogenic potential of this liver fluke. The review is based on a comprehensive analysis of the published medical data on opisthorchiasis and its complications in Western Siberia. Results of performed analysis reflect the actual epidemiological situation in opisthorchiasis focus and suggest an association of this disease with bile duct cancer. © The Author 2015. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  8. Schistosome and liver fluke derived catechol-estrogens and helminth associated cancers

    PubMed Central

    Correia da Costa, José M.; Vale, Nuno; Gouveia, Maria J.; Botelho, Mónica C.; Sripa, Banchob; Santos, Lúcio L.; Santos, Júlio H.; Rinaldi, Gabriel; Brindley, Paul J.

    2014-01-01

    Infection with helminth parasites remains a persistent public health problem in developing countries. Three of these pathogens, the liver flukes Clonorchis sinensis, Opisthorchis viverrini and the blood fluke Schistosoma haematobium, are of particular concern due to their classification as Group 1 carcinogens: infection with these worms is carcinogenic. Using liquid chromatography-mass spectrometry (LC-MS/MS) approaches, we identified steroid hormone like (e.g., oxysterol-like, catechol estrogen quinone-like, etc.) metabolites and related DNA-adducts, apparently of parasite origin, in developmental stages including eggs of S. haematobium, in urine of people with urogenital schistosomiasis, and in the adult stage of O. viverrini. Since these kinds of sterol derivatives are metabolized to active quinones that can modify DNA, which in other contexts can lead to breast and other cancers, helminth parasite associated sterols might induce tumor-like phenotypes in the target cells susceptible to helminth parasite associated cancers, i.e., urothelial cells of the bladder in the case of urogenital schistosomiasis and the bile duct epithelia or cholangiocytes, in the case of O. viverrini and C. sinensis. Indeed we postulate that helminth induced cancers originate from parasite estrogen-host epithelial/urothelial cell chromosomal DNA adducts, and here we review recent findings that support this conjecture. PMID:25566326

  9. Exploiting the ambulatory blood pressure monitoring via chronobiometric and chaosbiometric methods for a more exhaustive diagnostic approach to arterial hypertension.

    PubMed

    Cugini, P

    2008-01-01

    Presently, the ambulatory (A) blood (B) pressure (P) monitoring (M) is mainly used for diagnosing arterial hypertension (AH) in some special clinical conditions in which the causal sphygmomanometry appears not to be enough exhaustive. However, it must be pointed out that the actual approach to ABPM is almost simplistic, only consisting in a biometric analysis of discrete raw temporal values for systolic (S) and diastolic (D) BP and heart rate (HR). It must be stressed that BP and HR are hemodynamic variables characterized by a well established circadian rhythm (C) in their 24-h physiological values. Therefore, an appropriate chronobiometric approach, via Single Cosinor method, can improve the diagnostic value, its optimal oscillatory curve reducing all the biometric information to three parameters, i.e., MESOR (M, mean level of oscillation), Amplitude (A, extent of oscillation from M) and Acrophase (phi, timing of A with respect to local midnight). Accordingly, one can detect whether the BP CR is still manifest, as it is in essential hypertension (EH), or altered , as it is in secondary hypertension (SH). Therefore, by using the discriminant analysis for the three multivariate parameters, M, A, phi, of the BP cosine curve, one can statistically predict whether a new monitored hypertensive patient has a significant probability to be affected by EH or SH. Interestingly, by applying a further chronobiometric integration analysis, i.e., the Cosint analysis, it is possible to estimate the area under the BP oscillatory curve, for calculating the overall, diurnal, nocturnal, hourly pressure load (Baric Impact, BI) in terms respectively of mm2 Hg/24-h, mm2 Hg/16-h, mm2Hg/8-h, mm2 Hg/1-h. By comparing the overall BI of the new monitored hypertensive patient to its upper reference limit, one can estimate how much is the Baric Excess (Hyperbaric Impact, HI) caused by the personal hypertensive regimen. Finally, by using the chaos method of fractal interpolation to BP 24-h

  10. Preparation, transportation mechanisms and brain-targeting evaluation in vivo of a chemical delivery system exploiting the blood-cerebrospinal fluid barrier.

    PubMed

    Li, Ling; Tuo, Jue; Xie, Yanqi; Huang, Meihong; Huang, Min; Pi, Rongbiao; Hu, Haiyan

    2014-09-01

    In recent years, specific transportation mechanisms on the blood-brain barrier (BBB) are extensively employed for brain-targeted drug delivery via colloidal nanocarriers. However, in this study, we purposed to exploit the sodium-dependent vitamin C transporter 2 (SVCT2)-mediated transportation on the blood-cerebrospinal fluid barrier to enhance central nervous system penetration of the highly hydrophilic ibuprofen (IBU) by synthesizing a SVCT2-targeted chemical delivery system (CDS), ibuprofen-C6-O-ascorbic acid (IAA). The physicochemical parameters of IAA were determined, and the transporter-mediated transportation mechanism of IAA was explored on a BBB monolayer mode. The overall brain targeting effect of IAA was assayed on mice by measuring the biodistribution of IBU after i.v. administration and calculating the pharmacokinetic parameters and targeting indexes. Results showed that lipophilicity and solubility of IAA was conspicuously improved compared with IBU. At the physiological pH, IAA was stable while in brain homogenates it was easily degraded. Transport studies on the BBB monolayer mode revealed that IAA displayed higher transepithelial permeability than IBU via SVCT2. The biodistribution study in vivo demonstrated that the overall targeting efficiency of IAA was 1.77-fold greater than that of the IBU. In conclusion, the synthetic IAA might be a promising brain-targeted CDS for smuggling small-molecule hydrophilic pharmaceuticals into the brain.

  11. Molecular characterization of Fasciola flukes obtained from wild sika deer and domestic cattle in Hokkaido, Japan.

    PubMed

    Ichikawa-Seki, Madoka; Shiroma, Tomoko; Kariya, Tatsuya; Nakao, Ryo; Ohari, Yuma; Hayashi, Kei; Fukumoto, Shinya

    2017-10-01

    The number of wild sika deer (Cervus nippon yesoensis) continues to increase in Hokkaido Prefecture, Japan. The major concern for the livestock industry is the transmission of pathogens between sika deer and cattle. Fasciolosis is an important disease that can occur in both animals. The aim of this study was to examine the possible mutual transmission of this disease in Hokkaido Prefecture. A total of 105 Fasciola flukes were obtained from sika deer and 96 from domestic cattle. The Fasciola flukes in Japan are reported to possess no mature sperm. However, in this study, 14 flukes from sika deer and eight flukes from cattle contained mature sperm in their seminal vesicles. All the Fasciola flukes from the two host animals had Fh/Fg type in nuclear phosphoenolpyruvate carboxykinase (pepck) gene, with a mixed fragment pattern derived from F. hepatica and F. gigantica, which are considered to be hybrid Fasciola flukes. However, almost all the flukes had Fsp1 haplotype in NADH dehydrogenase subunit 1 (nad1) gene, indicating that their maternal lineage was F. hepatica. A new haplotype, Fsp3, was detected in one fluke obtained from cattle and differed in one nucleotide from Fsp1. Therefore, the Fasciola flukes detected in both host species had almost identical molecular characteristics. These findings suggest the mutual transmission of Fasciola flukes between sika deer and domestic cattle in Hokkaido. Copyright © 2017. Published by Elsevier B.V.

  12. Carcinogenic Liver Fluke and Others Contaminated in Pickled Fish of Northeastern Thailand

    PubMed

    Aukkanimart, Ratchadawan; Boonmars, Thidarut; Sriraj, Pranee; Sripan, Panupan; Songsri, Jiraporn; Ratanasuwan, Panaratana; Laummaunwai, Porntip; Suwanantrai, Apiporn; Aunpromma, Surasit; Khueangchaingkhwang, Sukhonthip; Pumhirunroj, Benjamabhorn; Artchayasawat, Atchara; Khuntikeo, Narong; Loilome, Watcharin; Namwat, Nisana; Yongvanit, Puangrat; Boonjaraspinyo, Sirintip

    2017-02-01

    Twenty provinces in northeastern Thailand were investigated for fluke metacercariae contamination in pickled fish, or pla-som, during January –June 2016. A total of 129 pickled fish shops were randomly chosen. Samples were digested with acid-pepsin and those found to be infected with metacercariae were fed to hamsters to test for metacercariae infectivity. The results demonstrated that only 20.2% of the pla-som samples were infected with fluke metacercariae (mc), at various levels (1 to 268 mc/kg). All recovered fluke metacercariae were inactive, degenerated and could not develop to adults in the animal model. In conclusion, the fluke mc infection status in pla-som was correlated with the prevalence of fluke infection in this region known for high O.viverrini and cholangiocarcinoma development. Clearly, systematic control of the fluke life cycle is needed. Whether pickling is an effective preventive measure needs further assessment. Creative Commons Attribution License

  13. Carcinogenic Liver Fluke and Others Contaminated in Pickled Fish of Northeastern Thailand

    PubMed Central

    Aukkanimart, Ratchadawan; Boonmars, Thidarut; Sriraj, Pranee; Sripan, Panupan; Songsri, Jiraporn; Ratanasuwan, Panaratana; Laummaunwai, Porntip; Suwanantrai, Apiporn; Aunpromma, Surasit; Khueangchaingkhwang, Sukhonthip; Pumhirunroj, Benjamabhorn; Artchayasawat, Atchara; Khuntikeo, Narong; Loilome, Watcharin; Namwat, Nisana; Yongvanit, Puangrat; Boonjaraspinyo, Sirintip

    2017-01-01

    Twenty provinces in northeastern Thailand were investigated for fluke metacercariae contamination in pickled fish, or pla-som, during January –June 2016. A total of 129 pickled fish shops were randomly chosen. Samples were digested with acid-pepsin and those found to be infected with metacercariae were fed to hamsters to test for metacercariae infectivity. The results demonstrated that only 20.2% of the pla-som samples were infected with fluke metacercariae (mc), at various levels (1 to 268 mc/kg). All recovered fluke metacercariae were inactive, degenerated and could not develop to adults in the animal model. In conclusion, the fluke mc infection status in pla-som was correlated with the prevalence of fluke infection in this region known for high O.viverrini and cholangiocarcinoma development. Clearly, systematic control of the fluke life cycle is needed. Whether pickling is an effective preventive measure needs further assessment. PMID:28345841

  14. Roles of liver fluke infection as risk factor for cholangiocarcinoma.

    PubMed

    Sithithaworn, Paiboon; Yongvanit, Puangrat; Duenngai, Kunyarat; Kiatsopit, Nadda; Pairojkul, Chawalit

    2014-05-01

    Several factors are known to be associated with risk of cholangiocarcinoma (CCA) and infection with the liver flukes, Opisthorchis viverrini and Clonorchis sinensis, has often been singled out as the leading risk factor in east and southeast Asia. In this review, current knowledge of their biology, life cycle, and pathogenesis of O. viverrini, and its role as a carcinogenic parasite are presented. The trends of age-specific incidence of liver cancer in Khon Kaen, northeast Thailand are considered and compared with the prevalence profiles of O. viverrini. Potential impacts of the liver fluke control program particularly by mass drug administration (MDA) and public health education in the past and a recent drop of incidence of CCA are discussed in relation to primary prevention and control of this fatal bile duct cancer. © 2014 Japanese Society of Hepato-Biliary-Pancreatic Surgery.

  15. Prospects and Challenges towards Sustainable Liver Fluke Control.

    PubMed

    Sripa, Banchob; Echaubard, Pierre

    2017-10-01

    The liver fluke Opisthorchis viverrini (Ov) is endemic in Southeast Asia where more than 10 million people are estimated to be infected. The infection is associated with several hepatobiliary diseases, including cholangiocarcinoma (CCA). Northeast Thailand is a hotspot for Ov transmission, and, despite extensive public health prevention campaigns led by the government, the prevalence of Ov infection is still high. High infection rates result from cultural and ecological complexities where wet-rice agrarian habitats, centuries-old raw-food culture, and the parasite's complex biology combine to create an ideal transmission arena. Here we review the state of our knowledge regarding the social-ecological determinants underlying Ov transmission. We also describe an integrative research rationale for liver fluke control better aligned with sustainable health development. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Large numbers of interleukins-22- and -17A-producing T helper cells in cholangiocarcinoma related to liver fluke infection.

    PubMed

    Su, Si-Biao; Zhang, Jian-Feng; Huang, Fei-Fei; Cen, Yu; Jiang, Hai-Xing

    2017-08-01

    Cholangiocarcinoma (CCA) associated with liver fluke infection involves inflammatory and immune processes; however, whether these involve the proinflammatory cytokine IL-17A and proliferative cytokine IL-22 remains unclear. Here, numbers of IL-22- and IL-17A-producing Th cells and cytokine concentrations in 30 patients with CCA and long-term liver fluke infection, 40 patients with liver-fluke infection but not CCA, and 16 healthy controls were compared. Analyses were performed using immunohistochemistry, flow cytometry, ELISA and RT-PCR. Immunohistochemical staining showed weaker expression of IL-22 and IL-17A in patients with CCA with than in those without liver fluke infection (P < 0.01). Flow cytometry revealed significantly greater median proportions of IL-22-producing T helper cells in patients with CCA (2.2%) than in those without it (0.69%) or controls (0.4%, P < 0.001). Similar results were obtained for IL-17A-producing T helper cells. ELISA revealed plasma concentrations of IL-22 were 1.3-fold higher in patients with CCA than in those without it and 4.6-fold higher than in controls (P < 0.001). Plasma concentrations of IL-17A were 2.5-fold higher in patients with CCA than in those without it, and 21-fold higher than in controls (P < 0.001). Amounts of IL-22 and IL-17A mRNAs in blood were significantly higher in patients with CCA than in the other two groups. Proportions of CD4(+) CD45RO(+) T cells producing IL-22 correlated with proportions producing IL-17A (r = 0.759; P < 0.001), and plasma concentrations of IL-22 correlated with those of IL-17A (r = 0.726; P < 0.001). These results suggest that both IL-17A and IL-22 affect development of CCA related to liver fluke infection. © 2017 The Societies and John Wiley & Sons Australia, Ltd.

  17. Gene discovery for the carcinogenic human liver fluke, Opisthorchis viverrini

    PubMed Central

    Laha, Thewarach; Pinlaor, Porntip; Mulvenna, Jason; Sripa, Banchob; Sripa, Manop; Smout, Michael J; Gasser, Robin B; Brindley, Paul J; Loukas, Alex

    2007-01-01

    Background Cholangiocarcinoma (CCA) – cancer of the bile ducts – is associated with chronic infection with the liver fluke, Opisthorchis viverrini. Despite being the only eukaryote that is designated as a 'class I carcinogen' by the International Agency for Research on Cancer, little is known about its genome. Results Approximately 5,000 randomly selected cDNAs from the adult stage of O. viverrini were characterized and accounted for 1,932 contigs, representing ~14% of the entire transcriptome, and, presently, the largest sequence dataset for any species of liver fluke. Twenty percent of contigs were assigned GO classifications. Abundantly represented protein families included those involved in physiological functions that are essential to parasitism, such as anaerobic respiration, reproduction, detoxification, surface maintenance and feeding. GO assignments were well conserved in relation to other parasitic flukes, however, some categories were over-represented in O. viverrini, such as structural and motor proteins. An assessment of evolutionary relationships showed that O. viverrini was more similar to other parasitic (Clonorchis sinensis and Schistosoma japonicum) than to free-living (Schmidtea mediterranea) flatworms, and 105 sequences had close homologues in both parasitic species but not in S. mediterranea. A total of 164 O. viverrini contigs contained ORFs with signal sequences, many of which were platyhelminth-specific. Examples of convergent evolution between host and parasite secreted/membrane proteins were identified as were homologues of vaccine antigens from other helminths. Finally, ORFs representing secreted proteins with known roles in tumorigenesis were identified, and these might play roles in the pathogenesis of O. viverrini-induced CCA. Conclusion This gene discovery effort for O. viverrini should expedite molecular studies of cholangiocarcinogenesis and accelerate research focused on developing new interventions, drugs and vaccines, to

  18. Apoptosis of cholangiocytes modulated by thioredoxin of carcinogenic liver fluke.

    PubMed

    Matchimakul, Pitchaya; Rinaldi, Gabriel; Suttiprapa, Sutas; Mann, Victoria H; Popratiloff, Anastas; Laha, Thewarach; Pimenta, Rafael N; Cochran, Christina J; Kaewkes, Sasithorn; Sripa, Banchob; Brindley, Paul J

    2015-08-01

    Chronic infection with the food-borne liver fluke, Opisthorchis viverrini, frequently induces cancer of the bile ducts, cholangiocarcinoma. Opisthorchiasis is endemic in Thailand, Lao PDR, Cambodia and Vietnam, where eating undercooked freshwater fish carrying the juvenile stage of this pathogen leads to human infection. Because inhibition of apoptosis facilitates carcinogenesis, this study investigated modulation by thioredoxin from O. viverrini of apoptosis of bile duct epithelial cells, cholangiocytes. Cells of a cholangiocyte line were incubated with the parasite enzyme after which they were exposed hydrogen peroxide. Oxidative stress-induced apoptosis was monitored using flow cytometry, growth in real time and imaging of living cells using laser confocal microscopy. Immunolocalization revealed liver fluke thioredoxin within cholangiocytes. Cells exposed to thioredoxin downregulated apoptotic genes in the mitogen activated protein kinases pathway and upregulated anti-apoptosis-related genes including apoptosis signaling kinase 1, caspase 9, caspase 8, caspase 3, survivin and others. Western blots of immunoprecipitates of cell lysates revealed binding of thioredoxin to apoptosis signaling kinase 1. Together the findings indicated that thioredoxin from O. viverrini inhibited oxidative stress-induced apoptosis of bile duct epithelial cells, which supports a role for this liver fluke oxidoreductase in opisthorchiasis-induced cholangiocarcinogenesis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Potential role of hares in the spread of liver fluke in the Netherlands.

    PubMed

    Walker, S M; Johnston, C; Hoey, E M; Fairweather, I; Borgsteede, F H M; Gaasenbeek, C P H; Prodohl, P A; Trudgett, A

    2011-04-19

    Hares (Lepus europeanus) sharing pasture with cattle from six locations in the Netherlands were examined for the presence of liver fluke (Fasciola hepatica) and shown to have prevalences of infection ranging from 0 to 41%. The mitochondrial haplotypes of liver flukes present in the hare populations were determined and compared with those found in cattle from a farm where triclabendazole resistance has been reported. Phylogenetic analysis indicated that the flukes present in the hares belonged to the same clades as those present in the cattle. A consideration of the life cycle of the liver fluke and the seasonal breeding pattern and ecology of hares supports the suggestion that hares may act as a refugia for liver fluke and as a vector for the spread of drug-resistant genotypes.

  20. ABC transporters in the liver fluke Opisthorchis felineus.

    PubMed

    Mordvinov, Viatcheslav A; Ershov, Nikita I; Pirozhkova, Darya S; Pakharukov, Yuri V; Pakharukova, Maria Y

    2017-09-01

    ATP-binding cassette transporters (ABC transporters) are essential components of normal cellular physiological machinery in all eukaryotic and prokaryotic species, including parasites. Some ABC transporters, e.g., P-glycoproteins, are involved in the efflux of toxins and xenobiotics from the cell. At present, nothing is known about ABC transporter genes in epidemiologically important liver flukes from the Opisthorchiidae family, including European liver fluke Opisthorchis felineus. Opisthorchiasis caused by O. felineus is a serious public health problem on the territory of Russia and other Eastern European countries. ABC drug transporters are attractive objects of research on molecular markers of resistance and on ways to potentiate sensitivity to anthelmintics through suppression of the transporters themselves with specific inhibitors. Here we aimed at the identification of ABC transporters in the O. felineus transcriptome and identification of P-glycoproteins. In addition, our aim was to assess ABC transcript abundance in the RNA-seq data, to study the mRNA expression of P-glycoprotein genes by Droplet Digital PCR throughout the life cycle of O. felineus, and to test the gene induction in response to xenobiotics or anthelminthic agents. We found 23 nucleotide sequences encoding ABC transporters belonging to different subfamilies, including four sequences of P-glycoproteins. According to the transcript abundance in the RNA-seq data, one of P-glycoproteins (P4) has the highest expression among all ABC genes in the adult worm. P-glycoproteins showed substantially differential mRNA expression throughout the fluke life cycle, with high expression in the adult worms. Putative activity of P-glycoproteins as xenobiotic efflux pumps was found to be linked to the excretory system of O. felineus and to be inhibited by verapamil or tariquidar. Thus, ABC drug transporters in the liver fluke O. felineus are functionally active, indicating that ABC drug transporters are likely

  1. Examination of the three-dimensional geometry of cetacean flukes using computed tomography scans: hydrodynamic implications.

    PubMed

    Fish, Frank E; Beneski, John T; Ketten, Darlene R

    2007-06-01

    The flukes of cetaceans function in the hydrodynamic generation of forces for thrust, stability, and maneuverability. The three-dimensional geometry of flukes is associated with production of lift and drag. Data on fluke geometry were collected from 19 cetacean specimens representing eight odontocete genera (Delphinus, Globicephala, Grampus, Kogia, Lagenorhynchus, Phocoena, Stenella, Tursiops). Flukes were imaged as 1 mm thickness cross-sections using X-ray computer-assisted tomography. Fluke shapes were characterized quantitatively by dimensions of the chord, maximum thickness, and position of maximum thickness from the leading edge. Sections were symmetrical about the chordline and had a rounded leading edge and highly tapered trailing edge. The thickness ratio (maximum thickness/chord) among species increased from insertion on the tailstock to a maximum at 20% of span and then decreasing steadily to the tip. Thickness ratio ranged from 0.139 to 0.232. These low values indicate reduced drag while moving at high speed. The position of maximum thickness from the leading edge remained constant over the fluke span at an average for all species of 0.285 chord. The displacement of the maximum thickness reduces the tendency of the flow to separate from the fluke surface, potentially affecting stall patterns. Similarly, the relatively large leading edge radius allows greater lift generation and delays stall. Computational analysis of fluke profiles at 50% of span showed that flukes were generally comparable or better for lift generation than engineered foils. Tursiops had the highest lift coefficients, which were superior to engineered foils by 12-19%. Variation in the structure of cetacean flukes reflects different hydrodynamic characteristics that could influence swimming performance.

  2. Molecular analysis of aspermic Fasciola flukes from Korea on the basis of the nuclear ITS1 region and mitochondrial DNA markers and comparison with Japanese aspermic Fasciola flukes.

    PubMed

    Ichikawa, Madoka; Itagaki, Tadashi

    2012-07-01

    It has been speculated that populations of aspermic Fasciola flukes in Korea and Japan have a close phylogenetic relationship. To evaluate this, we analyzed 33 Korean aspermic Fasciola flukes on the basis of nuclear ribosomal internal transcribed spacer 1 (ITS1) and mitochondrial NADH dehydrogenase subunit 1 (nad1) and cytochrome c oxidase 1 (cox1) sequences. Fh, Fg, and Fh/Fg types were detected in the ITS1 region and displayed the fragment patterns of F. hepatica, F. gigantica, and both species, respectively by a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Additionally, three concatenated haplotypes of nad1 and cox1(nad1/cox1) were detected, and 2 of these, Kor1/Kor1 (Fsp1/Fsp1) haplotype and Kor2a/Kor2 (Fsp2/Fsp2) haplotype, were shared by Korean and Japanese aspermic flukes. The Fst value (0.019), calculated using the concatenated sequences, indicated that Korean and Japanese aspermic Fasciola populations were genetically undifferentiated. Interestingly, a combination of the Fh/Fg type and Kor1/Kor1 haplotype was found at the highest frequency in Korean aspermic flukes, whereas the Fg type and Fsp2/Fsp2 haplotype combination was found at a conspicuously high frequency in Japanese aspermic flukes. This indicates that a founder effect caused by the introduction of infected hosts may have played a key role in the introduction of aspermic Fasciola flukes from Korea into Japan.

  3. Gene diversity and genetic variation in lung flukes (genus Paragonimus).

    PubMed

    Blair, David; Nawa, Yukifumi; Mitreva, Makedonka; Doanh, Pham Ngoc

    2016-01-01

    Paragonimiasis caused by lung flukes (genus Paragonimus) is a neglected disease occurring in Asia, Africa and the Americas. The genus is species-rich, ancient and widespread. Genetic diversity is likely to be considerable, but investigation of this remains confined to a few populations of a few species. In recent years, studies of genetic diversity have moved from isoenzyme analysis to molecular phylogenetic analysis based on selected DNA sequences. The former offered better resolution of questions relating to allelic diversity and gene flow, whereas the latter is more suitable for questions relating to molecular taxonomy and phylogeny. A picture is emerging of a highly diverse taxon of parasites, with the greatest diversity found in eastern and southern Asia where ongoing speciation might be indicated by the presence of several species complexes. Diversity of lung flukes in Africa and the Americas is very poorly sampled. Functional molecules that might be of value for immunodiagnosis, or as targets for medical intervention, are of great interest. Characterisation of these from Paragonimus species has been ongoing for a number of years. However, the imminent release of genomic and transcriptomic data for several species of Paragonimus will dramatically increase the rate of discovery of such molecules, and illuminate their diversity within and between species. © The Author 2015. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. Ionic composition of the liver fluke Fasciola hepatica from different mammalian hosts and comparison with host bile.

    PubMed

    Caseby, R H; Harriott, M; Fairweather, I

    1995-01-01

    A qualitative analysis of the cationic profile of bovine and ovine biles and of bovine, ovine and rat liver flukes has been carried out by DC arc emission spectrography. A quantitative assessment of the concentrations of Na+, K+, Ca2+ and Mg2+ ions in bovine, ovine and rat flukes has been determined by atomic absorption spectrophotometry. The levels of these ions in bovine and ovine bile samples have also been assessed and compared with those of Hédon-Heig saline. The ionic composition of the two biles is similar and the concentration of each ion is greater than that in Hédon-Heig saline. Despite the similarity in biles, ion levels in bovine flukes are generally higher than those in ovine flukes. Ion levels in rat flukes are different again but show closer similarity to those in bovine, not ovine, flukes. The results are discussed in relation to the proposed operation of the osmoregulatory system in the fluke.

  5. Forskolin activation of serotonin-stimulated adenylate cyclase in the liver fluke Fasciola hepatica.

    PubMed

    McNall, S J; Mansour, T E

    1985-05-15

    Properties of forskolin activation of adenylate cyclase in the liver fluke Fasciola hepatica are described. Forskolin stimulated adenylate cyclase activity in cell-free fluke particles to levels more than 30-fold above the basal rate. This activation was not dependent on guanine nucleotides and, upon washing of the particles, was rapidly reversed. Forskolin potentiated the activation of adenylate cyclase by serotonin (5-HT) and lysergic acid diethylamide (LSD), resulting in both an increase in the maximal level of enzyme activity and a decrease in the apparent activation constant (KA). The 5-HT antagonist 2-bromo-LSD did not inhibit enzyme activation by forskolin. Furthermore, forskolin had no effect on specific [3H]LSD binding to fluke particles. Activation of adenylate cyclase by sodium fluoride or guanine nucleotides was modified in a complex manner by forskolin with both stimulatory and inhibitory effects present. The results suggest that forskolin does not interact directly with the 5-HT receptor coupled to adenylate cyclase. Instead, it appears that forskolin effects are, at least in part, due to its ability to alter the interaction between the regulatory and catalytic components of adenylate cyclase. Incubation of intact flukes with forskolin increased their cAMP levels 2- to 3-fold. The concentration dependence of this response was similar to that for forskolin activation of adenylate cyclase in fluke particles, with 300 microM forskolin giving the maximum response. Forskolin and other agents that increased fluke cAMP levels also stimulated fluke motility.

  6. Intestinal fluke infection as a result of eating sushi.

    PubMed

    Adams, K O; Jungkind, D L; Bergquist, E J; Wirts, C W

    1986-11-01

    Severe diarrhea in a female outpatient was caused by an intestinal fluke, identified as Heterophyes heterophyes, a natural parasite of humans and domesticated and wild fish-eating mammals. This parasite is endemic in the Orient and the Middle East. A detailed case history revealed that the woman had never traveled outside the continental United States but became infected while eating raw fresh-water fish (sushi) that had been served at a local Japanese restaurant. The restaurant specialized in serving a great variety of fresh-water and salt-water fish that were flown in from the Orient and other parts of the world. The authors' findings indicate that a person does not have to travel to an endemic area to become infected with this organism.

  7. Developmental Transcriptomic Features of the Carcinogenic Liver Fluke, Clonorchis sinensis

    PubMed Central

    Cho, Pyo Yun; Kim, Tae Im; Cho, Shin-Hyeong; Choi, Sang-Haeng; Park, Hong-Seog; Kim, Tong-Soo; Hong, Sung-Jong

    2011-01-01

    Clonorchis sinensis is the causative agent of the life-threatening disease endemic to China, Korea, and Vietnam. It is estimated that about 15 million people are infected with this fluke. C. sinensis provokes inflammation, epithelial hyperplasia, and periductal fibrosis in bile ducts, and may cause cholangiocarcinoma in chronically infected individuals. Accumulation of a large amount of biological information about the adult stage of this liver fluke in recent years has advanced our understanding of the pathological interplay between this parasite and its hosts. However, no developmental gene expression profiles of C. sinensis have been published. In this study, we generated gene expression profiles of three developmental stages of C. sinensis by analyzing expressed sequence tags (ESTs). Complementary DNA libraries were constructed from the adult, metacercaria, and egg developmental stages of C. sinensis. A total of 52,745 ESTs were generated and assembled into 12,830 C. sinensis assembled EST sequences, and then these assemblies were further categorized into groups according to biological functions and developmental stages. Most of the genes that were differentially expressed in the different stages were consistent with the biological and physical features of the particular developmental stage; high energy metabolism, motility and reproduction genes were differentially expressed in adults, minimal metabolism and final host adaptation genes were differentially expressed in metacercariae, and embryonic genes were differentially expressed in eggs. The higher expression of glucose transporters, proteases, and antioxidant enzymes in the adults accounts for active uptake of nutrients and defense against host immune attacks. The types of ion channels present in C. sinensis are consistent with its parasitic nature and phylogenetic placement in the tree of life. We anticipate that the transcriptomic information on essential regulators of development, bile chemotaxis, and

  8. The Battle of Worldviews: A Case Study of Liver Fluke Infection in Khon Kaen, Thailand.

    PubMed

    Samiphak, Sara; Syme, S Leonard

    2017-01-01

    Control efforts to reduce infection from the parasitic flatworm Opisthorchis viverrini have progressed through understanding the epidemiology of Opisthorchis viverrini, antiparasitic drug developments, technological innovations, health education promoting cooking of fish, and improved hygienic defecation. Yet the problem persists. The case study method was used to examine the fundamental cause of the liver fluke infection problem. Evidence shows that the liver fluke-infected population does not care about living a long life. For them, suffering and death are simply a part of life, and expected. Thus, the cause(s) leading to death is not important. They believe morally bad actions, and predetermined fate associated with kamma in Buddhism, play a big role whether or not one is infected with the liver fluke. Health interventions may be made more effective if they take into account the liver fluke-infected population's worldviews about ethics, morality, life, and death. We researchers should not feel concerned only about medically determined causes of death.

  9. A new family of Monostome flukes (Platyhelminths, Digenea) from the dugong, Dugong dugon (Müller).

    PubMed

    Blair, D

    1979-01-01

    The family Labicolidae is erected to contain a new species of Monostome fluke occurring in abcesses in the upper lip of the dugong from northern Australia. Labicola elongata is described as a new species and figured.

  10. Blood

    MedlinePlus

    ... The liquid part, called plasma, is made of water, salts, and protein. Over half of your blood is plasma. The solid part of your blood contains red blood cells, white blood cells, and platelets. Red ...

  11. Taxonomic and Ecological Studies on the Lung Fluke, ’Paragonimus’ in Central and South America.

    DTIC Science & Technology

    In Tingo Maria, Peru, 25 crabs, Pseudothelphusa chilensis were examined for Paragonimus metacercariae with negative results. Five lung flukes were...minimus. These flukes belonged to the same species characterized by their extremely elongated body, and were named Paragonimus amazonicus sp. n. by...harbored 44 Paragonimus metacercariae in all. These larvae were divided into two species, five of them being identified as Paragonimus peruvianus and

  12. Three-Dimensional Geometry of the Narwhal (Monodon monoceros) Flukes in Relation to Hydrodynamics

    DTIC Science & Technology

    2011-10-01

    scales to improve discrimination of high-density elements. Images were obtained in DICOM formats, and for some data, were re- constructed at 100...archived onto magneto-optical disks for all scans in order to allow additional post-scan processing as needed. Image files were archived in DICOM format...and 512 matrices on CD. The DICOM images Table 1. Morphometrics of fluke planforms. Body Fluke Planform Aspect Sweepback Tusk Specimen Sex length (m

  13. Ostertagia spp., rumen fluke and liver fluke single- and poly-infections in cattle: An abattoir study of prevalence and production impacts in England and Wales.

    PubMed

    Bellet, C; Green, M J; Vickers, M; Forbes, A; Berry, E; Kaler, J

    2016-09-15

    This study aims at investigating the occurrence, risk factors and production impacts on beef carcass parameters of three of the most important cattle helminth infections in England and Wales. Abomasa, reticulorumens and livers from healthy cattle were collected and examined post-mortem quarterly over a one year period in an abattoir in South-West England. Specific viscera from 974 cattle were collected, examined and scored for Ostertagia spp., adult rumen fluke and liver fluke lesions/presence. A total of 89%, 25% and 29% of the carcasses had lesions/presence of Ostertagia spp., rumen fluke and liver fluke, respectively, and 39% had presence of helminth co-infection. Animal demographic and carcass parameters associated with helminth infections were investigated using multilevel multinomial and multilevel linear mixed models respectively. After adjusting for other factors, significant differences in the distribution of helminth infections were observed among cattle by type of breed, animal category (cow, heifer, steer and young bull), age, season and concurrent helminth infections. Compared to carcasses free of helminths, carcasses presenting solely Ostertagia Spp. lesions or adult rumen fluke had significantly lower cold carcass weight (coef.: -30.58 [-50.92;-10.24] and -50.34 [-88.50;-12.18]) and fat coverage (coef.: -3.28 [-5.56;-1.00] and -5.49 [-10.28;-0.69]) and carcasses presenting solely liver fluke lesions had significantly lower conformation grade (coef.: -3.65 [-6.98;-0.32]). Presence of helminth poly-infections was negatively associated with cold carcass weight.

  14. Simulating the Risk of Liver Fluke Infection using a Mechanistic Hydro-epidemiological Model

    NASA Astrophysics Data System (ADS)

    Beltrame, Ludovica; Dunne, Toby; Rose, Hannah; Walker, Josephine; Morgan, Eric; Vickerman, Peter; Wagener, Thorsten

    2016-04-01

    Liver Fluke (Fasciola hepatica) is a common parasite found in livestock and responsible for considerable economic losses throughout the world. Risk of infection is strongly influenced by climatic and hydrological conditions, which characterise the host environment for parasite development and transmission. Despite on-going control efforts, increases in fluke outbreaks have been reported in recent years in the UK, and have been often attributed to climate change. Currently used fluke risk models are based on empirical relationships derived between historical climate and incidence data. However, hydro-climate conditions are becoming increasingly non-stationary due to climate change and direct anthropogenic impacts such as land use change, making empirical models unsuitable for simulating future risk. In this study we introduce a mechanistic hydro-epidemiological model for Liver Fluke, which explicitly simulates habitat suitability for disease development in space and time, representing the parasite life cycle in connection with key environmental conditions. The model is used to assess patterns of Liver Fluke risk for two catchments in the UK under current and potential future climate conditions. Comparisons are made with a widely used empirical model employing different datasets, including data from regional veterinary laboratories. Results suggest that mechanistic models can achieve adequate predictive ability and support adaptive fluke control strategies under climate change scenarios.

  15. The role of evolutionary biology in research and control of liver flukes in Southeast Asia.

    PubMed

    Echaubard, Pierre; Sripa, Banchob; Mallory, Frank F; Wilcox, Bruce A

    2016-09-01

    Stimulated largely by the availability of new technology, biomedical research at the molecular-level and chemical-based control approaches arguably dominate the field of infectious diseases. Along with this, the proximate view of disease etiology predominates to the exclusion of the ultimate, evolutionary biology-based, causation perspective. Yet, historically and up to today, research in evolutionary biology has provided much of the foundation for understanding the mechanisms underlying disease transmission dynamics, virulence, and the design of effective integrated control strategies. Here we review the state of knowledge regarding the biology of Asian liver Fluke-host relationship, parasitology, phylodynamics, drug-based interventions and liver Fluke-related cancer etiology from an evolutionary biology perspective. We consider how evolutionary principles, mechanisms and research methods could help refine our understanding of clinical disease associated with infection by Liver Flukes as well as their transmission dynamics. We identify a series of questions for an evolutionary biology research agenda for the liver Fluke that should contribute to an increased understanding of liver Fluke-associated diseases. Finally, we describe an integrative evolutionary medicine approach to liver Fluke prevention and control highlighting the need to better contextualize interventions within a broader human health and sustainable development framework.

  16. Observations on the biology, epidemiology and economic relevance of rumen flukes (Paramphistomidae) in cattle kept in a temperate environment.

    PubMed

    Sargison, Neil; Francis, Emily; Davison, Chloe; Bronsvoort, Barend M deC; Handel, Ian; Mazeri, Stella

    2016-03-30

    There is concern about the probable recent introduction, increased prevalence and potential economic impact of rumen fluke infection of United Kingdom cattle. A study of 339 cattle slaughtered in a Scottish red meat abattoir was undertaken with the aims of describing the prevalence and geographical distribution of rumen fluke infection, estimating its effect on production, and evaluating faecal egg counts (FECs) as a tool to diagnose infection in live animals and study the epidemiology of the disease. The overall proportion of cattle consigned to the abattoir from northern United Kingdom with rumen fluke infection in the forestomachs was 0.29. Rumen flukes were distributed predominantly in the cranial sac of the rumen and adjacent to the reticular groove. Overall, a mean of 213 and median of 44 rumen flukes was identified in the forestomachs of rumen fluke-positive cattle. The mean and median FECs of animals were 26.01 and 5.20 eggs per gram (epg), respectively. There was a significant difference between the mean FECs per rumen fluke of 0.08 and 0.13 epg during summer/autumn and winter sampling periods, respectively. The overall correlation between rumen fluke FECs and the number of flukes in the forestomach was high, albeit lower in the summer/autumn than in the winter period. The sensitivities of rumen fluke FECs for the identification of flukes in the forestomach during the summer/autumn and winter sampling periods were 0.65 and 0.85, respectively. These results will aid in the interpretation of rumen fluke FECs when monitoring cattle health and production and studying the parasite's epidemiology in a temperate environment, thereby informing rational, precise and sustainable disease control. Copyright © 2016. Published by Elsevier B.V.

  17. Blood

    MedlinePlus

    ... that die or are lost from the body. White Blood Cells White blood cells (WBCs, and also ... of severe pain. previous continue Diseases of the White Blood Cells Neutropenia (pronounced: new-truh-PEE-nee- ...

  18. Fasciola hepatica: a comparative survey of adult fluke resistance to triclabendazole, nitroxynil and closantel on selected upland and lowland sheep farms in Northern Ireland using faecal egg counting, coproantigen ELISA testing and fluke histology.

    PubMed

    Hanna, R E B; McMahon, C; Ellison, S; Edgar, H W; Kajugu, P-E; Gordon, A; Irwin, D; Barley, J P; Malone, F E; Brennan, G P; Fairweather, I

    2015-01-15

    In order to investigate the incidence and distribution of adult fluke resistance to the fasciolicide tricalbendazole (TCBZ) amongst populations of Fasciola hepatica in sheep flocks in Northern Ireland (NI), individual rectal faeces samples were collected from 3 groups of 20 sheep, before (pre-dose), and 21 days after (post-dose) treatment of the animals with TCBZ, nitroxynil or closantel, on each of 13 well-managed sheep farms distributed across the province. The efficacy of each flukicide was determined for each farm, using faecal egg count reduction (FECRT) and F. hepatica coproantigen ELISA testing. In certain flocks, 2 sheep with high pre-dose faecal egg counts (FEC) were killed 3 days and 21 days respectively after TCBZ treatment, and the histology of the fluke reproductive organs was compared with that of flukes from untreated sheep, and from sheep treated with nitroxynil or closantel 2 days prior to death, using haematoxylin and eosin (H&E) staining and an in situ hybridisation method (TdT-mediated dUDP nick end labelling [TUNEL]) to demonstrate apoptosis. Results from FECRT revealed that in all flocks with a high fluke burden, TCBZ was ineffective in treating chronic fasciolosis, and this finding was generally supported by the results of the coproantigen reduction test (CRT). The histology of reproductive organs of flukes from TCBZ-treated sheep in these flocks was normal, when compared with untreated flukes, and this, together with the FECRT and CRT findings, indicated a likely diagnosis of TCBZ resistance in all the flocks with a high fluke burden. In contrast, nitroxynil and closantel were found to be fully effective against TCBZ-resistant flukes in each of the flocks bearing a high chronic fluke burden. All of the flocks with a high fluke burden and TCBZ resistance were managed on lowland in the South and East of NI. Upland flocks, in the North and West, had low fluke burdens, or were clear of infection; and FECs were too low to allow valid resistance

  19. Potential targeted therapy for liver fluke associated cholangiocarcinoma.

    PubMed

    Vaeteewoottacharn, Kulthida; Seubwai, Wunchana; Bhudhisawasdi, Vajarabhongsa; Okada, Seiji; Wongkham, Sopit

    2014-06-01

    Biliary tree cancer or cholangiocarcinoma (CCA) is an unusual subtype of liver cancer with exceptionally poor prognosis. Lack of specific symptoms and availability of early diagnostic markers account for late diagnosis of CCA. Surgical treatment is a gold standard choice but few patients are candidates and local recurrence after surgery is high. Benefit of systemic chemotherapy is limited; hence, better treatment options are required. The differences in etiology, anatomical positions and pathology make it difficult to generalize all CCA subtypes for a single treatment regimen. Herein, we review the uniqueness of molecular profiling identified by multiple approaches, for example, serial analysis of gene expression, exome sequencing, transcriptomics/proteomics profiles, protein kinase profile, etc., that provide the opportunity for treatment of liver fluke-associated CCA. Anti-inflammatory, immunomodulator/immunosuppressor, epidermal growth factor receptor or platelet-derived growth factor receptor inhibitors, multi-targeted tyrosine kinase inhibitor, IL6 antagonist, nuclear factor-κB inhibitor, histone modulator, proteasome inhibitor as well as specific inhibitors suggested from various study approaches, such as MetAP2 inhibitor, 1,25(OH)2 D3 and cyclosporine A are suggested in this review for the treatments of this specific CCA subtype. This might provide an alternative treatment option for CCA patients; however, clinical trials in this specific CCA group are required. © 2014 Japanese Society of Hepato-Biliary-Pancreatic Surgery.

  20. Occurrence of the lung fluke, Paragonimus heterotremus in Manipur, India.

    PubMed

    Singh, T Shantikumar

    2003-03-01

    To determine the natural crustacean host, the Paragonimus species, and to investigate the potential host-parasite relationship between Manipur Paragonimus and some of the laboratory animals. The laboratory animals such as puppies, albino rats and Swiss mice were infected orally with metacercariae isolated from the fresh water crabs, Potamiscus manipurensis. The fecal specimens of the experimentally infected animals were examined microscopically for Paragonimus eggs at regular intervals. The animals were autopsied on days 35 to approximately 328 after infection and the isolated worms were flattened between glass slides and fixed in 70% alcohol. The worms were stained with carmine and mounted with Canada balsam for morphological studies. The eggs were collected in 5% formol saline solution for microscopy. The flukes were classified into 4 developmental stages. A total of 11 worms, 5 mature, 5 immature and 1 pre-adult were recovered. The morphological features of the metacercariae, worms and eggs were similar to those of Paragonimus heterotremus. Manipur is one of the rare areas in the world where Paragonimus heterotremus is prevalent and the puppies are ideal experimental animal host. This species may be one of the important causes of paragonimiasis in animals and humans in Manipur.

  1. The draft genome of the carcinogenic human liver fluke Clonorchis sinensis.

    PubMed

    Wang, Xiaoyun; Chen, Wenjun; Huang, Yan; Sun, Jiufeng; Men, Jingtao; Liu, Hailiang; Luo, Fang; Guo, Lei; Lv, Xiaoli; Deng, Chuanhuan; Zhou, Chenhui; Fan, Yongxiu; Li, Xuerong; Huang, Lisi; Hu, Yue; Liang, Chi; Hu, Xuchu; Xu, Jin; Yu, Xinbing

    2011-10-24

    Clonorchis sinensis is a carcinogenic human liver fluke that is widespread in Asian countries. Increasing infection rates of this neglected tropical disease are leading to negative economic and public health consequences in affected regions. Experimental and epidemiological studies have shown a strong association between the incidence of cholangiocarcinoma and the infection rate of C. sinensis. To aid research into this organism, we have sequenced its genome. We combined de novo sequencing with computational techniques to provide new information about the biology of this liver fluke. The assembled genome has a total size of 516 Mb with a scaffold N50 length of 42 kb. Approximately 16,000 reliable protein-coding gene models were predicted. Genes for the complete pathways for glycolysis, the Krebs cycle and fatty acid metabolism were found, but key genes involved in fatty acid biosynthesis are missing from the genome, reflecting the parasitic lifestyle of a liver fluke that receives lipids from the bile of its host. We also identified pathogenic molecules that may contribute to liver fluke-induced hepatobiliary diseases. Large proteins such as multifunctional secreted proteases and tegumental proteins were identified as potential targets for the development of drugs and vaccines. This study provides valuable genomic information about the human liver fluke C. sinensis and adds to our knowledge on the biology of the parasite. The draft genome will serve as a platform to develop new strategies for parasite control.

  2. High prevalence of liver and intestinal fluke infections among residents of Savannakhet Province in Laos.

    PubMed

    Chai, Jong-Yil; Han, Eun-Taek; Guk, Sang-Mee; Shin, Eun-Hee; Sohn, Woon-Mok; Yong, Tai-Soon; Eom, Keeseon S; Lee, Keon-Hoon; Jeong, Hoo-Gn; Ryang, Yong-Sang; Hoang, Eui-Hyug; Phommasack, Bounlay; Insisiengmay, Bounnaloth; Lee, Soon-Hyung; Rim, Han-Jong

    2007-09-01

    The prevalence of liver and intestinal fluke infections was surveyed on residents of Savannakhet Province, Laos. Fecal specimens were collected from a total of 981 residents in 4 Mekong riverside villages and examined by the Kato-Katz thick smear technique. The results revealed that the overall helminth egg positive rate was 84.2%, and the positive rate for small trematode eggs, including Opisthorchis viverrini, heterophyids, or lecithodendriids, was 67.1%. To obtain adult flukes, 38 small trematode egg positive cases were treated with a 20-30 mg/kg single dose of praziquantel and purged. Diarrheic stools were then collected from 29 people and searched for helminth parasites using stereomicroscopes. Mixed infections with O. viverrini and 6 kinds of intestinal flukes were found, namely, Haplorchis taichui, Haplorchis pumilio, Haplorchis yokogawai, Prosthodendrium molenkampi, Phaneropsolus bonnei, and echinostomes. The total number of flukes collected was 7,693 specimens (av. no. per treated person; 265.3). The most common species was O. viverrini, followed by H. taichui, P. molenkampi, echinostomes, H. pumilio, P. bonnei, and H. yokogawai. The results indicate that foodborne liver and intestinal fluke infections are prevalent among residents of Savannakhet Province, Laos.

  3. High prevalence of liver and intestinal fluke infections among residents of Savannakhet Province in Laos

    PubMed Central

    Han, Eun-Taek; Guk, Sang-Mee; Shin, Eun-Hee; Sohn, Woon-Mok; Yong, Tai-Soon; Eom, Keeseon S.; Lee, Keon-Hoon; Jeong, Hoo-Gn; Ryang, Yong-Sang; Hoang, Eui-Hyug; Phommasack, Bounlay; Insisiengmay, Bounnaloth; Lee, Soon-Hyung; Rim, Han-Jong

    2007-01-01

    The prevalence of liver and intestinal fluke infections was surveyed on residents of Savannakhet Province, Laos. Fecal specimens were collected from a total of 981 residents in 4 Mekong riverside villages and examined by the Kato-Katz thick smear technique. The results revealed that the overall helminth egg positive rate was 84.2%, and the positive rate for small trematode eggs, including Opisthorchis viverrini, heterophyids, or lecithodendriids, was 67.1%. To obtain adult flukes, 38 small trematode egg positive cases were treated with a 20-30 mg/kg single dose of praziquantel and purged. Diarrheic stools were then collected from 29 people and searched for helminth parasites using stereomicroscopes. Mixed infections with O. viverrini and 6 kinds of intestinal flukes were found, namely, Haplorchis taichui, Haplorchis pumilio, Haplorchis yokogawai, Prosthodendrium molenkampi, Phaneropsolus bonnei, and echinostomes. The total number of flukes collected was 7,693 specimens (av. no. per treated person; 265.3). The most common species was O. viverrini, followed by H. taichui, P. molenkampi, echinostomes, H. pumilio, P. bonnei, and H. yokogawai. The results indicate that foodborne liver and intestinal fluke infections are prevalent among residents of Savannakhet Province, Laos. PMID:17876167

  4. Lesions caused by cardiovascular flukes (Digenea: Spirorchidae) in stranded green turtles (Chelonia mydas).

    PubMed

    Gordon, A N; Kelly, W R; Cribb, T H

    1998-01-01

    Evidence of infection with spirorchid flukes (Digenea: Spirorchidae) was sought at necropsy of 96 stranded green turtles, Chelonia mydas, that were examined during the course of a survey of marine turtle mortality in southeastern Queensland, Australia. Three species of spirorchid (Hapalotrema mehrai, H. postorchis, and Neospirorchis schistosomatoides) were identified. Severe disease due to spirorchid fluke infection (spirorchidiasis) was implicated as the principal cause of mortality in 10 turtles (10%), and appeared to be one of multiple severe problems in an additional 29 turtles (30%). Although flukes were observed in only 45% of stranded C. mydas in this study, presumed spirorchid fluke infection was diagnosed in an additional 53% of turtles, based principally on characteristic necropsy lesions and to a lesser extent on the histopathological detection of spirorchid eggs. Characteristic necropsy lesions included miliary spirorchid egg granulomas, which were observed most readily on serosal surfaces, particularly of the small intestine. Cardiovascular lesions included mural endocarditis, arteritis, and thrombosis, frequently accompanied by aneurysm formation. Resolution of thrombi was observed to occur via a combination of granuloma formation about indigestible components (spirorchid fluke egg shells) and exteriorization through the vessel wall, which resulted in granulomatous nodules on the adventitial surface. Septic aortic thrombosis complicated by disseminated bacterial infection, observed in five turtles, was recorded for the first time. Egg granulomas were ubiquitous in turtle tissues throughout this study. Although they generally appeared to be mild or incidental lesions, they were occasionally associated with severe multifocal granulomatous pneumonia or meningitis.

  5. The draft genome of the carcinogenic human liver fluke Clonorchis sinensis

    PubMed Central

    2011-01-01

    Background Clonorchis sinensis is a carcinogenic human liver fluke that is widespread in Asian countries. Increasing infection rates of this neglected tropical disease are leading to negative economic and public health consequences in affected regions. Experimental and epidemiological studies have shown a strong association between the incidence of cholangiocarcinoma and the infection rate of C. sinensis. To aid research into this organism, we have sequenced its genome. Results We combined de novo sequencing with computational techniques to provide new information about the biology of this liver fluke. The assembled genome has a total size of 516 Mb with a scaffold N50 length of 42 kb. Approximately 16,000 reliable protein-coding gene models were predicted. Genes for the complete pathways for glycolysis, the Krebs cycle and fatty acid metabolism were found, but key genes involved in fatty acid biosynthesis are missing from the genome, reflecting the parasitic lifestyle of a liver fluke that receives lipids from the bile of its host. We also identified pathogenic molecules that may contribute to liver fluke-induced hepatobiliary diseases. Large proteins such as multifunctional secreted proteases and tegumental proteins were identified as potential targets for the development of drugs and vaccines. Conclusions This study provides valuable genomic information about the human liver fluke C. sinensis and adds to our knowledge on the biology of the parasite. The draft genome will serve as a platform to develop new strategies for parasite control. PMID:22023798

  6. A case of a facultative life-cycle diversification in the fluke Pleurogenoides sp. (Lecithodendriidae, Plagiorchiida).

    PubMed

    Hassl, Andreas R

    2010-10-01

    Numerous specimens of the native, intestinal digenean fluke Pleurogenoides sp. (Lecithodendriidae, Plagiorchiida), a genus known for the simultaneous co-existence of genuine adults and progenetic, adult-like metacercaria, were found by chance parasitizing in the oesophagus of a recently imported, tropical Bristly Bush Viper (Atheris hispida). The snake had before been force-fed with native water frogs, the assumed definitive host of these flukes. Hence water frogs act as the second intermediate host or as a paratenic host for Pleurogenoides flukes, as they must house progenetic fluke larvae, which develop to genuine adults when transmitted to an appropriate consecutive host, the ancestral definitive host, a reptile. The European Pleurogenoides fluke species seem to display a facultative life-cycle diversification, they can adjust their life-history strategy according to their immediate transmission opportunities. This phenotypic plasticity allows the parasite to respond quickly to any changes in the abundance of a host; usually this biological oddity results in a life-cycle truncation by the elimination of the definitive host.

  7. Fasciola hepatica cathepsin L-like proteases: biology, function, and potential in the development of first generation liver fluke vaccines.

    PubMed

    Dalton, John P; Neill, Sandra O; Stack, Colin; Collins, Peter; Walshe, Alan; Sekiya, Mary; Doyle, Sean; Mulcahy, Grace; Hoyle, Deborah; Khaznadji, Eric; Moiré, Nathalie; Brennan, Gerard; Mousley, Angela; Kreshchenko, Natalia; Maule, Aaron G; Donnelly, Sheila M

    2003-09-30

    Fasciola hepatica secretes cathepsin L proteases that facilitate the penetration of the parasite through the tissues of its host, and also participate in functions such as feeding and immune evasion. The major proteases, cathepsin L1 (FheCL1) and cathepsin L2 (FheCL2) are members of a lineage that gave rise to the human cathepsin Ls, Ks and Ss, but while they exhibit similarities in their substrate specificities to these enzymes they differ in having a wider pH range for activity and an enhanced stability at neutral pH. There are presently 13 Fasciola cathepsin L cDNAs deposited in the public databases representing a gene family of at least seven distinct members, although the temporal and spatial expression of each of these members in the developmental stage of F. hepatica remains unclear. Immunolocalisation and in situ hybridisation studies, using antibody and DNA probes, respectively, show that the vast majority of cathepsin L gene expression is carried out in the epithelial cells lining the parasite gut. Within these cells the enzyme is packaged into secretory vesicles that release their contents into the gut lumen for the purpose of degrading ingested host tissue and blood. Liver flukes also express a novel multi-domain cystatin that may be involved in the regulation of cathepsin L activity. Vaccine trials in both sheep and cattle with purified native FheCL1 and FheCL2 have shown that these enzymes can induce protection, ranging from 33 to 79%, to experimental challenge with metacercariae of F. hepatica, and very potent anti-embryonation/hatch rate effects that would block parasite transmission. In this article we review the vaccine trials carried out over the past 8 years, the role of antibody and T cell responses in mediating protection and discuss the prospects of the cathepsin Ls in the development of first generation recombinant liver fluke vaccines.

  8. Protease Inhibitors of Parasitic Flukes: Emerging Roles in Parasite Survival and Immune Defence.

    PubMed

    Ranasinghe, Shiwanthi L; McManus, Donald P

    2017-05-01

    Protease inhibitors play crucial roles in parasite development and survival, counteracting the potentially damaging immune responses of their vertebrate hosts. However, limited information is currently available on protease inhibitors from schistosomes and food-borne trematodes. Future characterization of these molecules is important not only to expand knowledge on parasitic fluke biology but also to determine whether they represent novel vaccine and/or drug targets. Moreover, protease inhibitors from flukes may represent lead compounds for the development of a new range of therapeutic agents against inflammatory disorders and cancer. This review discusses already identified protease inhibitors of fluke origin, emphasizing their biological function and their possible future development as new intervention targets. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Evaluation of medicinal plant extracts against ticks and fluke.

    PubMed

    Elango, Gandhi; Rahuman, Abdul Abdul

    2011-03-01

    The present study was based on assessments of the antiparasitic activities to determine the efficacies of leaf hexane, chloroform, ethyl acetate, acetone and methanol extracts of Aegle marmelos (Linn.) Correa ex Roxb, Andrographis lineata Wallich ex Nees., Andrographis paniculata (Burm.f.) Wallich ex Nees., Cocculus hirsutus (L.) Diels, Eclipta prostrata L., and Tagetes erecta L. against the adult cattle tick Haemaphysalis bispinosa Neumann 1897 (Acarina: Ixodidae), the larvae of Rhipicephalus (Boophilus) microplus Canestrini 1887 (Acari: Ixodidae) and sheep fluke Paramphistomum cervi Zeder 1790 (Digenea: Paramphistomatidae). All plant extracts showed moderate toxic effect on parasites after 24 h of exposure; however, the highest parasitic activity was found in leaf ethyl acetate extract of A. lineata, methanol extract of A. marmelos, A. paniculata, and C. hirsutus against H. bispinosa (LC(50) = 395.27, 358.45, 327.21 and 420.50 ppm); ethyl acetate extract of A. paniculata, C. hirsutus, methanol extracts of A. marmelos, A. lineata, and E. prostrata against the larvae of R. microplus (LC(50) = 207.70, 258.61, 134.09, 206.00, and 274.33 ppm); hexane extract of A. lineata, ethyl acetate extract of A. paniculata, E. prostrata, acetone extracts of T. erecta, methanol extracts of A. marmelos and C. hirsutus against P. cervi (LC(50) = 254.23, 451.17, 425.73, 253.60, 542.71, and 360.17 ppm), respectively. The present study is the first report on the veterinary parasitic activity of plant extracts from Southern India.

  10. The Sigma class glutathione transferase from the liver fluke Fasciola hepatica.

    PubMed

    LaCourse, E James; Perally, Samirah; Morphew, Russell M; Moxon, Joseph V; Prescott, Mark; Dowling, David J; O'Neill, Sandra M; Kipar, Anja; Hetzel, Udo; Hoey, Elizabeth; Zafra, Rafael; Buffoni, Leandro; Pérez Arévalo, José; Brophy, Peter M

    2012-01-01

    Liver fluke infection of livestock causes economic losses of over US$ 3 billion worldwide per annum. The disease is increasing in livestock worldwide and is a re-emerging human disease. There are currently no commercial vaccines, and only one drug with significant efficacy against adult worms and juveniles. A liver fluke vaccine is deemed essential as short-lived chemotherapy, which is prone to resistance, is an unsustainable option in both developed and developing countries. Protein superfamilies have provided a number of leading liver fluke vaccine candidates. A new form of glutathione transferase (GST) family, Sigma class GST, closely related to a leading Schistosome vaccine candidate (Sm28), has previously been revealed by proteomics in the liver fluke but not functionally characterised. In this manuscript we show that a purified recombinant form of the F. hepatica Sigma class GST possesses prostaglandin synthase activity and influences activity of host immune cells. Immunocytochemistry and western blotting have shown the protein is present near the surface of the fluke and expressed in eggs and newly excysted juveniles, and present in the excretory/secretory fraction of adults. We have assessed the potential to use F. hepatica Sigma class GST as a vaccine in a goat-based vaccine trial. No significant reduction of worm burden was found but we show significant reduction in the pathology normally associated with liver fluke infection. We have shown that F. hepatica Sigma class GST has likely multi-functional roles in the host-parasite interaction from general detoxification and bile acid sequestration to PGD synthase activity.

  11. Infection with the carcinogenic liver fluke Opisthorchis viverrini modifies intestinal and biliary microbiome

    PubMed Central

    Plieskatt, Jordan L.; Deenonpoe, Raksawan; Mulvenna, Jason P.; Krause, Lutz; Sripa, Banchob; Bethony, Jeffrey M.; Brindley, Paul J.

    2013-01-01

    Opisthorchis viverrini is a fish-borne trematode endemic in East Asia. Following ingestion, the flukes locate to the biliary treȩ where chronic infection frequently leads to cholangiocarcinoma (CCA). The mechanisms by which O. viverrini infection culminates in CCA remain unknown. An unexplored aspect is its influence on the host microbiome. In the hamster, infection with this pathogen reliably leads to CCA. Genomic DNAs of microbiota from colorectal contents and bile of hamsters and from whole O. viverrini were examined in this model of fluke-induced CCA. Microbial communities were characterized by high-throughput sequencing of variable regions 7–9 of prokaryotic 16S ribosomal DNA. Of ∼1 million sequences, 536,009 with useable reads were assignable to 29,776 operational taxonomy units (OTUs) and, in turn, to 20 phyla and 273 genera of Bacteria or Archaea. Microbial community analyses revealed that fluke infection perturbed the gastrointestinal tract microbiome, increasing Lachnospiraceae, Ruminococcaceae, and Lactobacillaceae, while decreasing Porphyromonadaceae, Erysipelotrichaceae, and Eubacteriaceae (P≤0.05). More than 60 OTUs were detected in the biliary system, which confirmed bacteriobilia and a noteworthy community of microbes associated with the parasites. The fluke-associated microorganisms included potential pathogens from the Enterobacteriaceae and Listeriaceae and others, including Cyanobacteria and Deinococci, usually found in external environments. Given that opisthorchiasis is distinguished from other helminth infections by a robust inflammatory phenotype with conspicuously elevated IL-6, and that inflammation of the biliary system leads to periductal fibrosis, which is a precursor of CCA, the flukes and their microbiota may together drive this distinctive immune response.—Plieskatt, J. L., Raksawan, D., Mulvenna, J. P., Krause, L., Sripa, B., Bethony, J. M., Brindley, P. J. Infection with the carcinogenic liver fluke Opisthorchis viverrini

  12. Experimental infection of liver flukes, Fasciola hepatica and Fascioloides magna, in Bison (Bison bison).

    PubMed

    Foreyt, William J; Drew, M L

    2010-01-01

    This experimental study was conducted to evaluate the susceptibility of American bison (Bison bison) to liver flukes, Fascioloides magna and Fasciola hepatica. Six bison were each experimentally inoculated with 600 metacercariae of Fascioloides magna, and three were later treated with triclabendazole suspension at 40 mg/kg of body weight. Four additional bison were each experimentally inoculated with 600 metacercariae of Fasciola hepatica. Five control bison were placebo controls. Two controls and all inoculated bison were euthanized 10 mo (Fascioloides magna) and 7 mo (Fasciola hepatica) after inoculation. None of the control bison or the bison inoculated with Fascioloides magna had flukes or lesions characteristic of fluke infection at necropsy. All four bison inoculated with Fasciola hepatica had characteristic liver fluke lesions at necropsy, and three of four bison contained four, 103, and 111 adult flukes, respectively. Fluke eggs were detected in feces of all Fasciola hepatica-inoculated bison during the experiment, but not from the Fascioloides magna-infected bison or control bison. Clinical signs of infection were not observed during the experiment, but hemoglobin and packed cell volumes were lower in the Fasciola hepatica bison when compared to controls, and eosinophil levels were increased. Triclabendazole at 40 mg/kg of body weight appeared to be safe in bison because no toxic reactions were observed. Results from this study indicated bison are susceptible to infection with Fasciola hepatica and are efficient definitive hosts. Because no Fascioloides magna were recovered, bison may have a decreased susceptibility or innate resistance to Fascioloides magna infection, which may account for a lack of reported infections in this host.

  13. The Sigma Class Glutathione Transferase from the Liver Fluke Fasciola hepatica

    PubMed Central

    LaCourse, E. James; Perally, Samirah; Morphew, Russell M.; Moxon, Joseph V.; Prescott, Mark; Dowling, David J.; O'Neill, Sandra M.; Kipar, Anja; Hetzel, Udo; Hoey, Elizabeth; Zafra, Rafael; Buffoni, Leandro; Pérez Arévalo, José; Brophy, Peter M.

    2012-01-01

    Background Liver fluke infection of livestock causes economic losses of over US$ 3 billion worldwide per annum. The disease is increasing in livestock worldwide and is a re-emerging human disease. There are currently no commercial vaccines, and only one drug with significant efficacy against adult worms and juveniles. A liver fluke vaccine is deemed essential as short-lived chemotherapy, which is prone to resistance, is an unsustainable option in both developed and developing countries. Protein superfamilies have provided a number of leading liver fluke vaccine candidates. A new form of glutathione transferase (GST) family, Sigma class GST, closely related to a leading Schistosome vaccine candidate (Sm28), has previously been revealed by proteomics in the liver fluke but not functionally characterised. Methodology/Principal Findings In this manuscript we show that a purified recombinant form of the F. hepatica Sigma class GST possesses prostaglandin synthase activity and influences activity of host immune cells. Immunocytochemistry and western blotting have shown the protein is present near the surface of the fluke and expressed in eggs and newly excysted juveniles, and present in the excretory/secretory fraction of adults. We have assessed the potential to use F. hepatica Sigma class GST as a vaccine in a goat-based vaccine trial. No significant reduction of worm burden was found but we show significant reduction in the pathology normally associated with liver fluke infection. Conclusions/Significance We have shown that F. hepatica Sigma class GST has likely multi-functional roles in the host-parasite interaction from general detoxification and bile acid sequestration to PGD synthase activity. PMID:22666515

  14. Effects of the injectable contraceptive depot medroxyprogesterone acetate in Thai women with liver fluke infestation: results after six months

    PubMed Central

    Grossman, Richard A.; Assawasena, Vinich; Chalpati, Sopon; Taewtong, Dilok

    1977-01-01

    The effect of the three-monthly injectable contraceptive depot medroxyprogesterone acetate (DMPA) on liver and lipid function was assessed in Thai women with liver fluke (Opisthorchis viverrini) infestation, DMPA administration being started in the immediate postpartum period. Immediate postpartum IUD and sterilization acceptors with fluke infestation were recruited as a comparison (control) group for the fluke-positiv DMPA acceptors. Comparable groups of fluke-negative acceptors were recruited in an area of Thailand free of liver fluke transmission. Results are presented for the first 6 follow-up months for 170 DMPA and 177 control fluke-positive subjects and for 153 DMPA and 150 control fluke-negative subjects. Small and similar increases occurred in each of the four groups for alanine amino transferase, isocitrate dehydrogenase, and total bilirubin levels while aspartate amino transferase levels changed less in the DMPA groups than in their respective control groups. None of the subjects in either DMPA group had clearly abnormal results in these tests at 6 months. Alkaline phosphatase, cholesterol, and triglycerides levels were markedly lower in each group at 6 months than in the puerperal specimens. There was a greater decrease in triglycerides levels in both DMPA groups than in their respective control groups. However, the decrease in the alkaline phosphatase and cholesterol levels was greater only in the fluke-positive DMPA group than in the fluke-positive control group. None of these biochemical results were related to differences in age, parity, or lactation status between the groups. The results indicate that DMPA did not cause any early deleterious effects in the metabolic factors studied in women with liver fluke infestation. PMID:302157

  15. Behavioral Modification Regarding Liver Fluke and Cholangiocarcinoma with a Health Belief Model Using Integrated Learning.

    PubMed

    Phatisena, Panida; Eaksanti, Tawatchai; Wichantuk, Pitsanee; Tritipsombut, Jaruwan; Kaewpitoon, Soraya J; Rujirakul, Ratana; Wakkhuwattapong, Parichart; Tongtawee, Taweesak; Matrakool, Likit; Panpimanmas, Sukij; Norkaew, Jun; Kujapun, Jirawoot; Chavengkun, Wasugree; Kompor, Porntip; Pothipim, Mali; Ponphimai, Sukanya; Padchasuwan, Natnapa; Kaewpitoon, Natthawut

    2016-01-01

    This study aimed to modify behavior regarding liver fluke and cholangiocarcinoma prevention in Chumphuang district, Nakhon Ratchasima province, Thailand through integrated learning. A total of 180 participants were included through purposive selection of high-risk scores on verbal screening. Participants attended the health education program which applied the health belief model included family based, knowledge station based, academic merit based and community based learning. Data were collected using a questionnaire composed of 4 parts: 1) personal information, 2) knowledge, 3) perceived susceptibility, severity, benefits, and barriers, 4) practice regarding liver fluke and cholangiocarcinoma prevention. The result revealed that the majority were female (79.9%), age ≥60 years old (33.2%), primary school educational level (76.1%), and agricultural occupation (70.1%). The mean scores of knowledge, perception, and practice to liver fluke and cholangiocarcinoma prevention, before participated the integrative learning were low, moderate, and low, respectively. Meanwhile, the mean score of knowledge, perceived susceptibility, severity, benefits, and barriers, and practice regarding liver fluke and cholangiocarcinoma prevention, were higher with statistical significance after participation in the integrated learning. This finding indicates that health education programs may successfully modify health behavior in the rural communities. Therefore they may useful for further work behavior modification in other epidemic areas.

  16. A model to assess the efficacy of vaccines for control of liver fluke infection.

    PubMed

    Turner, Joanne; Howell, Alison; McCann, Cathy; Caminade, Cyril; Bowers, Roger G; Williams, Diana; Baylis, Matthew

    2016-03-24

    Fasciola hepatica, common liver fluke, infects cattle and sheep causing disease and production losses costing approximately $3 billion annually. Current control relies on drugs designed to kill the parasite. However, resistance is evident worldwide and widespread in some areas. Work towards a vaccine has identified several antigens of F. hepatica that show partial efficacy in terms of reducing worm burden and egg output. A critical question is what level of efficacy is required for such a vaccine to be useful? We have created the first mathematical model to assess the effectiveness of liver fluke vaccines under simulated field conditions. The model describes development of fluke within a group of animals and includes heterogeneity in host susceptibility, seasonal exposure to metacercariae and seasonal changes in temperature affecting metacercarial survival. Our analysis suggests that the potential vaccine candidates could reduce total fluke burden and egg output by up to 43% and 99%, respectively, on average under field conditions. It also suggests that for a vaccine to be effective, it must protect at least 90% of animals for the whole season. In conclusion, novel, partial, vaccines could contribute substantially towards fasciolosis control, reducing usage of anthelmintics and thus delaying the spread of anthelmintic resistance.

  17. Prevalence and Sequence-Based Identity of Rumen Fluke in Cattle and Deer in New Caledonia.

    PubMed

    Cauquil, Laura; Hüe, Thomas; Hurlin, Jean-Claude; Mitchell, Gillian; Searle, Kate; Skuce, Philip; Zadoks, Ruth

    2016-01-01

    An abattoir survey was performed in the French Melanesian archipelago of New Caledonia to determine the prevalence of paramphistomes in cattle and deer and to generate material for molecular typing at species and subspecies level. Prevalence in adult cattle was high at animal level (70% of 387 adult cattle) and batch level (81%). Prevalence was lower in calves at both levels (33% of 484 calves, 51% at batch level). Animals from 2 of 7 deer farms were positive for rumen fluke, with animal-level prevalence of 41.4% (29/70) and 47.1% (33/70), respectively. Using ITS-2 sequencing, 3 species of paramphistomes were identified, i.e. Calicophoron calicophorum, Fischoederius elongatus and Orthocoelium streptocoelium. All three species were detected in cattle as well as deer, suggesting the possibility of rumen fluke transmission between the two host species. Based on heterogeneity in ITS-2 sequences, the C. calicophorum population comprises two clades, both of which occur in cattle as well as deer. The results suggest two distinct routes of rumen fluke introduction into this area. This approach has wider applicability for investigations of the origin of rumen fluke infections and for the possibility of parasite transmission at the livestock-wildlife interface.

  18. A model to assess the efficacy of vaccines for control of liver fluke infection

    PubMed Central

    Turner, Joanne; Howell, Alison; McCann, Cathy; Caminade, Cyril; Bowers, Roger G.; Williams, Diana; Baylis, Matthew

    2016-01-01

    Fasciola hepatica, common liver fluke, infects cattle and sheep causing disease and production losses costing approximately $3billion annually. Current control relies on drugs designed to kill the parasite. However, resistance is evident worldwide and widespread in some areas. Work towards a vaccine has identified several antigens of F. hepatica that show partial efficacy in terms of reducing worm burden and egg output. A critical question is what level of efficacy is required for such a vaccine to be useful? We have created the first mathematical model to assess the effectiveness of liver fluke vaccines under simulated field conditions. The model describes development of fluke within a group of animals and includes heterogeneity in host susceptibility, seasonal exposure to metacercariae and seasonal changes in temperature affecting metacercarial survival. Our analysis suggests that the potential vaccine candidates could reduce total fluke burden and egg output by up to 43% and 99%, respectively, on average under field conditions. It also suggests that for a vaccine to be effective, it must protect at least 90% of animals for the whole season. In conclusion, novel, partial, vaccines could contribute substantially towards fasciolosis control, reducing usage of anthelmintics and thus delaying the spread of anthelmintic resistance. PMID:27009747

  19. Prevalence and Sequence-Based Identity of Rumen Fluke in Cattle and Deer in New Caledonia

    PubMed Central

    Cauquil, Laura; Hüe, Thomas; Hurlin, Jean-Claude; Mitchell, Gillian; Searle, Kate; Skuce, Philip; Zadoks, Ruth

    2016-01-01

    An abattoir survey was performed in the French Melanesian archipelago of New Caledonia to determine the prevalence of paramphistomes in cattle and deer and to generate material for molecular typing at species and subspecies level. Prevalence in adult cattle was high at animal level (70% of 387 adult cattle) and batch level (81%). Prevalence was lower in calves at both levels (33% of 484 calves, 51% at batch level). Animals from 2 of 7 deer farms were positive for rumen fluke, with animal-level prevalence of 41.4% (29/70) and 47.1% (33/70), respectively. Using ITS-2 sequencing, 3 species of paramphistomes were identified, i.e. Calicophoron calicophorum, Fischoederius elongatus and Orthocoelium streptocoelium. All three species were detected in cattle as well as deer, suggesting the possibility of rumen fluke transmission between the two host species. Based on heterogeneity in ITS-2 sequences, the C. calicophorum population comprises two clades, both of which occur in cattle as well as deer. The results suggest two distinct routes of rumen fluke introduction into this area. This approach has wider applicability for investigations of the origin of rumen fluke infections and for the possibility of parasite transmission at the livestock-wildlife interface. PMID:27043709

  20. Galectin secretion and binding to adult Fasciola hepatica during chronic liver fluke infection of sheep.

    PubMed

    Young, Anna R; Barcham, Garry J; McWilliam, Hamish E; Piedrafita, David M; Meeusen, Els N

    2012-01-15

    Galectins are increasingly recognised as important mediators of immune homeostasis and disease regulation, but comparatively little is known about their role in parasite infection. This study investigates the interaction between two ovine galectins, galectin-11 and galectin-14, and the parasitic liver fluke, F. hepatica. Galectin-14 was found in eosinophils infiltrating the tissue surrounding infected bile ducts and secreted in the connective tissue, while galectin-11 was specifically induced in epithelial cells of bile ducts from infected sheep. Strong nuclear staining was observed for galectin-11. Both galectins were found to be secreted into the bile fluid of parasite infected sheep, and were also detected in the excretory/secretory products of adult flukes, following their removal from the ovine host. Recombinant galectin-14, but not recombinant galectin-11, was found to bind specifically to the surface tegument of adult flukes in a carbohydrate dependent manner. This study shows for the first time that both galectin-14 and galectin-11 are produced in liver tissue after chronic liver fluke infection and that they can directly interact with the parasite in the bile ducts. Galectin-11 may also be involved in epithelial cell turnover and cancerogenesis. Copyright © 2011 Elsevier B.V. All rights reserved.

  1. Fluke (Spirorchiidae) infections in sea turtles stranded on Taiwan: prevalence and pathology.

    PubMed

    Chen, Hochang; Kuo, R-J; Chang, T-C; Hus, C-K; Bray, R A; Cheng, I-J

    2012-04-01

    The prevalence of spirorchiid fluke infections of marine turtles is high and may cause the death of the hosts throughout their ranges. Virtually nothing has been reported regarding the infective status of sea turtles stranded on Taiwan. Between 2007 and 2010, 30 green turtles (Chelonia mydas) and 2 loggerhead turtles ( Caretta caretta ), stranded and dead, were examined for spirorchiid flukes and their eggs. Twenty-four of the green turtles were juveniles, and the stranded loggerhead turtles were subadults. Adult spirorchiid flukes were found in 13 green turtles but not in the loggerheads. Four species of flukes were identified, namely, Leardius learedi , Hapalotrema postorchis , H. mehrai , and Carettacola hawaiiensis . The main infection sites were the major arteries and heart. Seventy percent of the green turtles harbored spirorchiid eggs, but no eggs were found in loggerheads. The largest eggs with bipolar spines, type I eggs, were found in every case. Although more than half of the stranded turtles were infected, parasite infections were not the main cause of death in the green turtles. Fishery by-catch is probably responsible for the mortality of these stranded turtles.

  2. Association between Liver Fluke Infection and Hepatobiliary Pathological Changes: A Systematic Review and Meta-Analysis.

    PubMed

    Xia, Jing; Jiang, Shi-chen; Peng, Hong-Juan

    2015-01-01

    To provide information about the role of liver fluke infection as a risk factor for hepatobiliary pathological changes and promote awareness among the people living in endemic areas, a systematic review and meta-analysis based on published studies was conducted to examine the association between liver fluke infection and hepatobiliary pathological changes. Relevant original literature was searched in multiple literature databases, including PubMed, Cochrane, Clinical Evidence, Trip Database, Clinical Trials, Current Controlled Trials, Web of Science, the China National Knowledge Infrastructure (CNKI) database, and the Wanfang academic journal full-text database. Studies were selected based on strict screening with inclusion and exclusion criteria. Tests of heterogeneity, sensitivity and publication bias were performed with the Review Manager software, version 5.3, and meta-regression analyses were performed with the Stata software, version 11.0 (Stata Corporation, College Station, TX, USA). Pooled risk ratios (RRs) and odds ratios (ORs) with their 95% confidence intervals (95% CIs) were calculated and used to evaluate the risk of hepatobiliary pathological changes resulting from liver fluke infection. Linear trend analyses were conducted to determine the dose-response relationship using IBM SPSS Statistics 20.0. A total of 36 studies were included in the meta-analysis. Significant associations were found between liver fluke infection and cholangitis or cholecystitis (RR: 7.80, P<0.001; OR: 15.98, P<0.001), cholelithiasis (RR: 2.42, P = 0.03; OR: 4.96, P = 0.03), hepatocellular carcinoma (OR: 4.69, P<0.001) and cholangiocarcinoma (RR: 10.43, P<0.001; OR: 4.37, P<0.001). In addition, heavier infection was significantly associated with higher incidence of hepatobiliary pathological changes (P<0.05). However, cirrhosis was not significantly associated with liver fluke infection (RR: 3.50, P = 0.06; OR: 5.79, P = 0.08). The statistical heterogeneity was significant, no

  3. Novel insights into the pathogenic importance, diagnosis and treatment of the rumen fluke (Calicophoron daubneyi) in cattle.

    PubMed

    Malrait, Karen; Verschave, Sien; Skuce, Philip; Van Loo, Hans; Vercruysse, Jozef; Charlier, Johannes

    2015-01-15

    Recently, sharp increases in the prevalence of rumen fluke infections have been recorded throughout Western Europe. However, scarce information is available on the diagnosis, pathogenic importance and control of this parasite. We undertook 3 pilot studies to gain more insights into these aspects of rumen fluke biology in cattle. First, we evaluated the diagnostic performance of mini-FLOTAC to detect adult rumen fluke infections based on faecal egg count in an abattoir survey and found high sensitivity (0.94) and specificity (0.98). Moreover, there was an association between ruminal fluke burden (assessed by visual scoring) and faecal egg count and a cut-off of 200 eggs per gram is proposed to detect highly infected animals (>200 flukes present in the rumen and/or reticulum). There was also a significant association between ruminal fluke burden and faecal consistency. However, in a second study, we performed a case-control field survey to investigate the association between rumen fluke infection and herd-level problems with diarrhoea and no association was found. Finally, we evaluated the use of closantel (Flukiver(®), Elanco Animal Health, subcutaneous administration at 10mg/kg) to treat rumen fluke infection on 3 herds, but no significant reduction in egg output post-treatment was found. Because this result is in contrast with a previous study using an oral dose of closantel, more research is required into the effect of administration route on the efficacy of closantel on rumen fluke. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Co-infections with liver fluke and Helicobacter species: A paradigm change in pathogenesis of opisthorchiasis and cholangiocarcinoma?

    PubMed

    Sripa, Banchob; Deenonpoe, Raksawan; Brindley, Paul J

    2017-08-01

    Infection with the fish-borne liver fluke Opisthorchis viverrini is classified by the International Agency for Research on Cancer as a Group 1 carcinogen: definitely carcinogenic in humans. Cofactors likely contribute to bile duct cancer (cholangiocarcinoma) caused by this infection. Here we review recent findings that address the role of liver fluke associated H. pylori in hepatobiliary disease and malignancy. We hypothesize that co-infection by O. viverrini and the bacillus Helicobacter pylori is central of liver fluke infection associated cholangiocarcinoma. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  5. Liver fluke prevention and control in the northeast of Thailand through action research.

    PubMed

    Wongba, N; Thaewnongiew, K; Phathee, K; Laithavewat, L; Duangsong, R; Promthet, S; Tangsawad, S

    2011-01-01

    The aim of this action research was to enhance people's potential to prevent and control liver fluke infestation. The subjects were a total of 96 participants comprising 20 community leaders, 74 individuals handling and preparing food, and 2 officials from the Local Administration. Quantitative data were collected through questionnaire and the results of stool examination of the participants were recorded. The main methods used to collect qualitative data were focus group discussions and in-depth interviews. For qualitative data analysis, the researchers undertook a qualitative content analysis. For quantitative data, conventional descriptive statistics were used and the mean differences with the 95% CI before and after the study were compared. The results in the early stage found that the participants were not aware of the fact that eating raw fish might be the cause of developing cholangiocarcinoma. 94.8% of participants however knew that eating raw fish might be cause having liver fluke infection which can be treated be taking an antihelminthic drug. They perceived that it is way of life since their ancestors already consumed raw fish because they found it to be delicious. However, through participating in this study, it was realized how dangerous it is to get infected with the liver fluke. Participants also learned the life cycle of liver fluke. They talked about this within their families, and communicated as well as cooperated with others to strengthen a network of a club concentrating on not eating raw fish. The communities and the Sub-district Administrative Organization supported the project. In conclusion, it is advisable to improve the behavior of participants in villages so that they became aware how to prevent and control liver fluke infection and therefore the development of cholangiocarcinoma.

  6. Blood

    MedlinePlus

    ... spans vary from a few days to months. New cells are constantly being formed in the bone marrow. ... the bloodstream and are constantly being replaced by new cells. Blood also contains important proteins called clotting factors , ...

  7. Exploitability Assessment with TEASER

    DTIC Science & Technology

    2017-05-01

    executable xor writable, or that executable images cannot have write permissions over the course of the program’s execution. DWARF Debugging With...feature a Proof of Concept (POC), or input to a program demonstrating the ability to use a bug to exploit the application. For example, a recent write -up...TEASER Exploit Development Workflow Tainted Malloc Reads, Tainted Function Arguments, Tainted Pointer Reads/ Writes , Tainted Data Reads Tainted

  8. Modifying Health Behavior for Liver Fluke and Cholangiocarcinoma Prevention with the Health Belief Model and Social Support Theory.

    PubMed

    Padchasuwan, Natnapa; Kaewpitoon, Soraya J; Rujirakul, Ratana; Wakkuwattapong, Parichart; Norkaew, Jun; Kujapun, Jirawoot; Ponphimai, Sukanya; Chavenkun, Wasugree; Kompor, Pontip; Kaewpitoon, Natthawut

    2016-01-01

    The liver fluke Opisthorchis viverrini is a serious health problem in Thailand. Infection is associated with cholangiocarcinoma (CCA), endemic among human populations in northeast and north Thailand where raw fish containing fluke metacercariae are frequently consumed. Recently, Thailand public health authorities have been organized to reduce morbidity and mortality particularly in the northeast through O. viverrini and CCA screening projects. Health modfication is one of activities included in this campaign, but systemic guidelines of modifying and developing health behavior for liver flukes and CCA prevention in communities towards health belief and social support theory are still various and unclear. Here we review the guidelines for modifying and developing health behavior among populations in rural communities to strengthen understanding regarding perceived susceptibility, severity, benefits, and barriers to liver fluke and CCA prevention. This model may be useful for public health of cancers and related organizations to further health behavior change in endemic areas.

  9. Opisthorchis viverrini-like liver fluke in birds from Vietnam: morphological variability and rDNA/mtDNA sequence confirmation.

    PubMed

    Dao, T H; Nguyen, T G; Victor, B; Gabriël, S; Dorny, P

    2014-12-01

    Flukes were found in the bile ducts of domestic ducks (Anas platyrhynchos), necropsied in the Binh Dinh province of Central Vietnam. Following staining, morphological characteristics of the bird flukes were compatible with Opisthorchis viverrini, although some characteristics differed from those described in specimens collected from mammal hosts. Computation of the phylogenetic trees on the partial sequences of the second internal ribosomal spacer (ITS2) of the ribosomal DNA and cytochrome c oxidase subunit I (COI) markers of the mitochondrial DNA showed close similarity of the 'bird' Opisthorchis sp. with O. viverrini. We speculate that these bird flukes are O. viverrini that show intraspecies morphological and molecular variability compared to isolates from mammals. This demonstrates the complex epidemiological situation of opisthorchiasis in Vietnam and urges investigations on the potential of birds as a reservoir host of this zoonotic fluke.

  10. Suppression of aquaporin, a mediator of water channel control in the carcinogenic liver fluke, Opisthorchis viverrini.

    PubMed

    Thanasuwan, Sirikanda; Piratae, Supawadee; Brindley, Paul J; Loukas, Alex; Kaewkes, Sasithorn; Laha, Thewarach

    2014-05-14

    Opisthorchiasis and Opisthorchis viverrini-associated bile duct cancer represent major public health threats in Thailand and Laos. The tegument of this food borne fluke plays pivotal roles in parasite metabolism, homeostasis and osmoregulation. Excretory/secretory products also pass from the fluke to the biliary environment, products that likely underlie pathogenesis of liver fluke infection. Aquaporins (AQPs), belong to the major intrinsic protein superfamily of integral plasma membrane channel proteins that selectively transport water across cell membranes. AQPs play key roles as water and ion transport channels through the tegument of helminth parasites. Here, two forms of AQP mRNAs from the adult developmental stage of O. viverrini, termed O. viverrini aquaporin-1 and -2 (Ov-aqp-1 and -2) were investigated. Roles of Ov-aqp-1 and -2 in the movement of water across the tegument of this carcinogenic liver fluke were investigated using RNA interference. Ov-AQP-1 and Ov-AQP-2 contain unique characteristic asparagine-proline-alanine (NPA) motifs of AQP transmembrane proteins. Phylogenetic analysis indicated that Ov-AQPs belong to an expanding group of aquaglyceroporin-like water channel proteins characterized from helminth and protozoan parasites, which is pivotal to the specialized requirements of water and solute control during parasitism. Elevated transcription of Ov-aqp-1 was evident in the egg, cercaria, metacercaria and adult stages of O. viverrini, whereas Ov-aqp-2 transcripts were detected at higher level in egg, metacercaria, cercaria and adult stage, respectively. RNA interference using electroporated dsRNA suppressed transcript levels of Ov-aqp-1 and Ov-aqp-2 in adult worms by 58-99% over periods of up to 16 days in vitro. Suppression of Ov-aqp-1 and Ov-aqp-2 in vitro disabled water transport in adult flukes. The apparently pivotal roles of Ov-AQP in solute homeostasis at the fluke surface suggest that deeper investigation will be informative for the

  11. Opisthorchis viverrini (liver fluke) as the lot of baleful parasite of tropical region-A replete synopsis

    PubMed Central

    Gundamaraju, Rohit; Vemuri, Ravi Chandra

    2014-01-01

    Liver fluke disease is a chronic parasitic inflammatory disease of the bile ducts which is highly prominent in the tropical regions. Infection occurs through ingestion of fluke-infested fresh-water raw fish. Opisthorchis viverrini is the biggest causative organism for this disease. Adult flukes get into the body of humans and settle in the small intrahepatic bile ducts, and then they live there for few decades. The long-lived flukes cause long-lasting chronic inflammation of the bile ducts, and this produces epithelial hyperplasia, periductal fibrosis and bile duct dilatation. Major complications of the disease also include pancreatitis, bile duct obstruction etc. The majority of patients are asymptomatic, but the patients with heavy infection suffer from lassitude and nonspecific abdominal complaints. Approximately 35 million people are infected with liver flukes throughout the world and the exceptionally high incidence of cholangiocarcinoma in some endemic areas is closely related with a high prevalence of liver fluke infection. Considering the appulse of this food-borne malady on accessible bloom and the astringent accessible analytic consequences, alarmist accident infection should not be abandoned or neglected. This review acts as a complete picture in elucidating the information regarding the parasite and disease condition thereby supporting the researchers worldwide.

  12. Population dynamics and host reactions in young foxes following experimental infection with the minute intestinal fluke, Haplorchis pumilio

    PubMed Central

    2013-01-01

    Background Infections with fish-borne zoonotic trematodes (FZT) including the minute intestinal fluke, Haplorchis pumilio, are highly prevalent in Southeast Asia. However, little is known about the infection dynamics and clinical symptoms in the final hosts which include a range of animal species and man. We aimed to generate such information using an experimental model with H. pumilio in foxes. Method Eight commercially bred foxes were each orally infected with 2000 H. pumilio metacercariae. Another three foxes served as uninfected controls. Faecal examination for eggs was performed twice weekly. The body weight was measured, standard haematological and biochemical analysis were performed regularly. All foxes were euthanized at day 56 post infection (p.i.). Adult worms were quantified and location in the small intestine noted. Results Anorexia was observed in all infected foxes starting day 12 p.i. and lasting for approximately a week. A weight loss was noticed in the infected group in weeks 3–6 p.i. Five of eight infected foxes excreted H. pumilio eggs day 9 p.i. onwards, the remaining three started on day 13 p.i. Mean (± SD) faecal egg counts showed an initial peak at day 16–20 with a maximum of 1443 ± 1176 eggs per gram of faeces (epg), where after a stable egg output around 4–500 epg was seen. Worm burdens ranged between 116–2070 adult flukes with a mean (± SD) worm recovery of 948 ± 666. The majority of worms were found in the lower part of the jejunum. Total white blood cell and lymphocyte counts were significant lower in the infected group from first week p.i. onwards and throughout the study period. A significantly lower level of eosinophils was found in week 2 p.i. and transient anaemia was seen in week 2 and 4 p.i. Conclusion This study showed a short prepatency period, an initial peak in egg excretion, establishment of infection in all animals with predilection site in the lower jejunum and a marked but transient clinical effect of

  13. Population dynamics and host reactions in young foxes following experimental infection with the minute intestinal fluke, Haplorchis pumilio.

    PubMed

    Nissen, Sofie; Thamsborg, Stig Milan; Kania, Per Walther; Leifsson, Páll S; Dalsgaard, Anders; Johansen, Maria Vang

    2013-01-04

    Infections with fish-borne zoonotic trematodes (FZT) including the minute intestinal fluke, Haplorchis pumilio, are highly prevalent in Southeast Asia. However, little is known about the infection dynamics and clinical symptoms in the final hosts which include a range of animal species and man. We aimed to generate such information using an experimental model with H. pumilio in foxes. Eight commercially bred foxes were each orally infected with 2000 H. pumilio metacercariae. Another three foxes served as uninfected controls. Faecal examination for eggs was performed twice weekly. The body weight was measured, standard haematological and biochemical analysis were performed regularly. All foxes were euthanized at day 56 post infection (p.i.). Adult worms were quantified and location in the small intestine noted. Anorexia was observed in all infected foxes starting day 12 p.i. and lasting for approximately a week. A weight loss was noticed in the infected group in weeks 3-6 p.i. Five of eight infected foxes excreted H. pumilio eggs day 9 p.i. onwards, the remaining three started on day 13 p.i. Mean (± SD) faecal egg counts showed an initial peak at day 16-20 with a maximum of 1443 ± 1176 eggs per gram of faeces (epg), where after a stable egg output around 4-500 epg was seen. Worm burdens ranged between 116-2070 adult flukes with a mean (± SD) worm recovery of 948 ± 666. The majority of worms were found in the lower part of the jejunum. Total white blood cell and lymphocyte counts were significant lower in the infected group from first week p.i. onwards and throughout the study period. A significantly lower level of eosinophils was found in week 2 p.i. and transient anaemia was seen in week 2 and 4 p.i. This study showed a short prepatency period, an initial peak in egg excretion, establishment of infection in all animals with predilection site in the lower jejunum and a marked but transient clinical effect of the infection. The findings on egg output and

  14. The Exploitation of Drug Users.

    PubMed

    Stallings, Shirley; Montagne, Michael

    2015-01-01

    Drug users have been exploited in research studies and clinical practice. We explore ways in which exploitation has occurred and strategies to help patients, research subjects and communities to prevent or avoid exploitation.

  15. Phyllodistomum kanae sp. nov. (Trematoda: Gorgoderidae), a bladder fluke from the Ezo salamander Hynobius retardatus.

    PubMed

    Nakao, Minoru

    2015-10-01

    The Ezo salamander, Hynobius retardatus, is endemic only to Hokkaido, the northernmost island of Japan. Gravid flukes of the family Gorgoderidae were discovered from the urinary bladder of H. retardatus. The parasites were identified as a new species named Phyllodistomum kanae sp. nov. In the neighboring Honshu island another bladder fluke, Phyllodistomum patellare, has already been found from the Japanese newt. The new species clearly differs from P. patellare in having a spherical ovary and very weakly lobed testes. The discovery of species of Phyllodistomum from urodelan amphibians is very uncommon in Eurasia. A molecular phylogeny based on 28S ribosomal DNA suggests that sphaeriid bivalves may serve as the first intermediate host for the new species.

  16. The tumorigenic liver fluke Opisthorchis viverrini –multiple pathways to cancer

    PubMed Central

    Sripa, Banchob; Brindley, Paul J.; Mulvenna, Jason; Laha, Thewarach; Smout, Michael J; Mairiang, Eimorn; Bethony, Jeffrey M.; Loukas, Alex

    2012-01-01

    Liver fluke infection caused by Opisthorchis viverrini is a major public health problem in Thailand and adjacent countries. In addition to infection-associated morbidity, infection with O. viverrini and the related Clonorchis sinensis are unarguable risk factors for cholangiocarcinoma, bile duct cancer. Here we review the pathogenesis of opisthorchiasis and the association of O. viverrini infection and bile duct cancer, focusing on the molecular parallels between wound healing, chronic inflammation and cancer development. We review a schema for human disease progression from fluke infection, chronic opisthorchiasis, advanced periductal fibrosis, and cholangiocarcinogenesis, and present a rationale for biomarker discovery to facilitate early intervention. We conclude by addressing post-genomic advances with a view to developing new control strategies to combat this infectious cancer. PMID:22947297

  17. [Genomics and transcriptomics of the Chinese liver fluke Clonorchis sinensis (Opisthorchiidae, Trematoda)].

    PubMed

    Chelomina, G N

    2017-01-01

    The review summarizes the results of first genomic and transcriptomic investigations of the liver fluke Clonorchis sinensis (Opisthorchiidae, Trematoda). The studies mark the dawn of the genomic era for opisthorchiids, which cause severe hepatobiliary diseases in humans and animals. Their results aided in understanding the molecular mechanisms of adaptation to parasitism, parasite survival in mammalian biliary tracts, and genome dynamics in the individual development and the development of parasite-host relationships. Special attention is paid to the achievements in studying the codon usage bias and the roles of mobile genetic elements (MGEs) and small interfering RNAs (siRNAs). Interspecific comparisons at the genomic and transcriptomic levels revealed molecular differences, which may contribute to understanding the specialized niches and physiological needs of the respective species. The studies in C. sinensis provide a basis for further basic and applied research in liver flukes and, in particular, the development of efficient means to prevent, diagnose, and treat clonorchiasis.

  18. Comparative proteomic analysis of triclabendazole response in the liver fluke Fasciola hepatica.

    PubMed

    Chemale, Gustavo; Perally, Samirah; LaCourse, E James; Prescott, Mark C; Jones, Laura M; Ward, Deborah; Meaney, Myles; Hoey, Elizabeth; Brennan, Gerard P; Fairweather, Ian; Trudgett, Alan; Brophy, Peter M

    2010-10-01

    Control of Fasciola hepatica infections of livestock in the absence of vaccines depends largely on the chemical triclabendazole (TCBZ) because it is effective against immature and adult parasites. Overdependence on a single drug and improper application is considered a significant factor in increasing global reports of fluke resistant to TCBZ. The mode(s) of action and biological target(s) of TCBZ are not confirmed, delaying detection and the monitoring of early TCBZ resistance. In this study, to further understand liver fluke response to TCBZ, the soluble proteomes of TCBZ-resistant and TCBZ-susceptible isolates of F. hepatica were compared with and without in vitro exposure to the metabolically active form of the parent drug triclabendazole sulphoxide (TCBZ-SO), via two-dimensional gel electrophoresis (2-DE). Gel image analysis revealed proteins displaying altered synthesis patterns and responses both between isolates and under TCBZ-SO exposure. These proteins were identified by mass spectrometry supported by a F. hepatica expressed sequence tag (EST) data set. The TCBZ responding proteins were grouped into three categories; structural proteins, energy metabolism proteins, and "stress" response proteins. This single proteomic investigation supported the reductionist experiments from many laboratories that collectively suggest TCBZ has a range of effects on liver fluke metabolism. Proteomics highlighted differences in the innate proteome profile of different fluke isolates that may influence future therapy and diagnostics design. Two of the TCBZ responding proteins, a glutathione transferase and a fatty acid binding protein, were cloned, produced as recombinants, and both found to bind TCBZ-SO at physiologically relevant concentrations, which may indicate a role in TCBZ metabolism and resistance.

  19. Untangling the Complexity of Liver Fluke Infection and Cholangiocarcinoma in NE Thailand Through Transdisciplinary Learning.

    PubMed

    Ziegler, A D; Echaubard, P; Lee, Y T; Chuah, C J; Wilcox, B A; Grundy-Warr, C; Sithithaworn, P; Petney, T N; Laithevewat, L; Ong, X; Andrews, R H; Ismail, T; Sripa, B; Khuntikeo, N; Poonpon, K; Tungtang, P; Tuamsuk, K

    2016-06-01

    This study demonstrates how a transdisciplinary learning approach provided new insights for explaining persistent Opisthorchis viverrini infection in northern Thailand, as well as elucidating problems of focusing solely on the parasite as a means of addressing high prevalence of cholangiocarcinoma. Researchers from diverse backgrounds collaborated to design an investigative homestay program for 72 Singaporean and Thai university students in five northeast Thai villages. The students explored how liver fluke infection and potential cholangiocarcinoma development are influenced by local landscape dynamics, aquatic ecology, livelihoods, food culture and health education. Qualitative fieldwork was guided daily by the researchers in a collaborative, co-learning process that led to viewing this health issue as a complex system, influenced by interlinked multidimensional factors. Our transdisciplinary experience has led us to believe that an incomplete understanding of these linkages may reduce the efficacy of interventions. Further, viewing liver fluke infection and cholangiocarcinoma as the same issue is inadvisable. Although O. viverrini infection is an established risk factor for the development of cholangiocarcinoma, multiple factors are known to influence the likelihood of acquiring either. Understanding the importance of the current livelihood transition, landscape modification and the resulting mismatch between local cultures and new socio-ecological settings on cholangiocarcinoma initiation and liver fluke transmission is of critical importance as it may help readjust our view of the respective role of O. viverrini and other socioeconomic risk factors in cholangiocarcinoma etiology and refine intervention strategies. As demonstrated in this study, transdisciplinary approaches have the potential to yield more nuanced perspectives to complex diseases than research that focuses on specific aspects of their epidemiology. They may therefore be valuable when designing

  20. Nutritional Status among Rural Community Elderly in the Risk Area of Liver Fluke, Surin Province, Thailand.

    PubMed

    Kaewpitoon, Soraya J; Namwichaisirikul, Niwatchai; Loyd, Ryan A; Churproong, Seekaow; Ueng-Arporn, Naporn; Matrakool, Likit; Tongtawee, Taweesak; Rujirakul, Ratana; Nimkhuntod, Porntip; Wakhuwathapong, Parichart; Kaewpitoon, Natthawut

    2015-01-01

    Thailand is becoming an aging society, this presenting as a serious problem situation especially regarding health. Chronic diseases found frequently in the elderly may be related to dietary intake and life style. Surin province has been reported as a risk area for liver fluke with a high incidence of cholangiocarcinma especially in the elderly. Therefore, this study aimed to determine the nutritional status and associated factors among elderly in Surin province, northeast of Thailand. A community-based cross-sectional study was conducted among 405 people aged 60 years and above, between September 2012 and July 2014. The participants were selected through a randomized systematic sampling method and completed a pre-designed questionnaire with general information, food recorded, weight, height, waist circumference, and behavior regarding to food consume related to liver fluke infection. The data were analyzed using descriptive statistics and Spearman's rank correlation coefficients. The majority of participants was female (63.5%), age between 60-70 years old (75.6%), with elementary school education (96.6%), living with their (78.9%), and having underlying diseases (38.3%). Carbohydrate (95.3%) was need to improve the consumption. The participants demonstrated under-nutrition (24.4%), over-nutrition (16.4%), and obesity (15.4%). Elderly had a waist circumference as the higher than normal level (34.0%). Gender, female, age 71-80 years old, elementary school and underlying diseases were significantly associated with poor nutritional status. The majority of them had a high knowledge (43.0%), moderate attitude (44.4%), and moderate practice (46.2%) regarding food consumption related to liver fluke infection. In conclusion, these findings data indicated that elderly age group often have an under- or over-nutritional status. Carbohydrate consumption needs to be improved. Some elderly show behavior regarding food consumption that is related to liver fluke infection hat needs

  1. Characterization of the antioxidant enzyme, thioredoxin peroxidase, from the carcinogenic human liver fluke, Opisthorchis viverrini

    PubMed Central

    Suttiprapa, Sutas; Loukas, Alex; Laha, Thewarach; Wongkham, Sopit; Kaewkes, Sasithorn; Gaze, Soraya; Brindley, Paul J.; Sripa, Banchob

    2013-01-01

    The human liver fluke, Opisthorchis viverrini, induces inflammation of the hepatobiliary system. Despite being constantly exposed to inimical oxygen radicals released from inflammatory cells, the parasite survives for many years. The mechanisms by which it avoids oxidative damage are unknown. In this study, thioredoxin peroxidase (TPx), a member of the peroxiredoxin superfamily, was cloned from an O. viverrini cDNA library. O. viverrini TPx cDNA encoded a polypeptide of 212 amino acid residues, of molecular mass 23.57 kDa. The putative amino acid sequence shared 60-70% identity with TPXs from other helminths and from mammals, and phylogenetic analysis revealed a close relationship between TPxs from O. viverrini and other trematodes. Recombinant O. viverrini TPx was expressed as soluble protein in Escherichia coli. The recombinant protein dimerized, and its antioxidant activity was deduced by observing protection of nicking of supercoiled plasmid DNA by hydroxyl radicals. Antiserum raised against O. viverrini TPx recognized native proteins from egg, metacercaria and adult developmental stages of the liver fluke and excretory-secretory products released by adult O. viverrini. Immunolocalization studies revealed ubiquitous expression of TPx in O. viverrini organs and tissues. TPx was also detected in bile fluid and bile duct epithelial cells surrounding the flukes two weeks after infection of hamsters with O. viverrini. In addition, TPx was observed in the secondary (small) bile ducts where flukes cannot reach due to their large size. These results suggested that O. viverrini TPx plays a significant role in protecting the parasite against damage induced by reactive oxygen species from inflammation. PMID:18538872

  2. Characterization of the antioxidant enzyme, thioredoxin peroxidase, from the carcinogenic human liver fluke, Opisthorchis viverrini.

    PubMed

    Suttiprapa, Sutas; Loukas, Alex; Laha, Thewarach; Wongkham, Sopit; Kaewkes, Sasithorn; Gaze, Soraya; Brindley, Paul J; Sripa, Banchob

    2008-08-01

    The human liver fluke, Opisthorchis viverrini, induces inflammation of the hepatobiliary system. Despite being constantly exposed to inimical oxygen radicals released from inflammatory cells, the parasite survives for many years. The mechanisms by which it avoids oxidative damage are unknown. In this study, thioredoxin peroxidase (TPx), a member of the peroxiredoxin superfamily, was cloned from an O. viverrini cDNA library. O. viverrini TPx cDNA encoded a polypeptide of 212 amino acid residues, of molecular mass 23.57kDa. The putative amino acid sequence shared 60-70% identity with TPXs from other helminths and from mammals, and phylogenetic analysis revealed a close relationship between TPxs from O. viverrini and other trematodes. Recombinant O. viverrini TPx was expressed as soluble protein in Escherichia coli. The recombinant protein dimerized, and its antioxidant activity was deduced by observing protection of nicking of supercoiled plasmid DNA by hydroxyl radicals. Antiserum raised against O. viverrini TPx recognized native proteins from egg, metacercaria and adult developmental stages of the liver fluke and excretory-secretory products released by adult O. viverrini. Immunolocalization studies revealed ubiquitous expression of TPx in O. viverrini organs and tissues. TPx was also detected in bile fluid and bile duct epithelial cells surrounding the flukes 2 weeks after infection of hamsters with O. viverrini. In addition, TPx was observed in the secondary (small) bile ducts where flukes cannot reach due to their large size. These results suggested that O. viverrini TPx plays a significant role in protecting the parasite against damage induced by reactive oxygen species from inflammation.

  3. In vitro antihelmintic effect of fifteen tropical plant extracts on excysted flukes of Fasciola hepatica.

    PubMed

    Alvarez-Mercado, José Manuel; Ibarra-Velarde, Froylán; Alonso-Díaz, Miguel Ángel; Vera-Montenegro, Yolanda; Avila-Acevedo, José Guillermo; García-Bores, Ana María

    2015-02-27

    Fasciolosis due to Fasciola hepatica is the most important hepatic disease in veterinary medicine. Its relevance is important because of the major economical losses to the cattle industry such as: reduction in milk, meat and wool production; miscarriages, anemia, liver condemnation and occasionally deaths, are estimated in billons of dollars. The emergence of fluke resistance due to over or under dosing of fasciolides as well as environmental damage produced by the chemicals eliminated in field have stimulated the need for alternative methods to control Fasciola hepatica. The aim of this study was to evaluate the in vitro anthelmintic effect of fifteen tropical plant extracts used in tradicional Mexican medicine, on newly excysted flukes of Fasciola hepatica. The flukes were exposed in triplicate at 500, 250 and 125 mg/L to each extract. The efficacy was assessed as the mortality rate based on the number of live and dead flukes after 24, 48 and 72 h post-exposure. The plants with anthelmintic effect were evaluated once again with a concentration of 375 mg/L in order to confirm the results and to calculate lethal concentrations at 50%, 90% and 99% (LC(50), LC(90), and LC(99)). Plant extracts of Lantana camara, Bocconia frutescens, Piper auritum, Artemisia mexicana and Cajanus cajan had an in vitro anthelmintic effect (P <0.05). The LC(50), LC(90) and LC(99) to A. mexicana, C. cajan and B. frutescens were 92.85, 210.44 and 410.04 mg/L, 382.73, 570.09 and 788.9 mg/L and 369.96, 529.94 and 710.34 mg/L, respectively. It is concluded that five tropical plant extracts had promising anthelmintic effects against F. hepatica. Further studies on toxicity and in vivo biological evaluation in ruminant models might help to determine the anthelmintic potential of these plant extracts.

  4. Pesticides, fresh water fish, liver flukes and nitrosamines: A story of cholangiocarcinoma development in Thailand.

    PubMed

    Wiwanitkit, Viroj

    2009-01-01

    Cholangiocarcinoma is a common hepatobiliary carcinoma in Thailand. It is believed that both chronic exposure to liver fluke infestation and nitrosamine exposure are the two main underlying factors leading to the carcinogenesis. Here, the author further extrapolates and proposes a new hypothesis based on the environmental ecological data that the stimulation of fresh water fish by contaminated pesticide in water reservoirs might be a possible background of the high prevalence of cholangiocarcinoma in Thailand.

  5. Proteomic profile of Bithynia siamensis goniomphalos snails upon infection with the carcinogenic liver fluke Opisthorchis viverrini

    PubMed Central

    Prasopdee, Sattrachai; Tesana, Smarn; Cantacessi, Cinzia; Laha, Thewarach; Mulvenna, Jason; Grams, Rudi; Loukas, Alex; Sotillo, Javier

    2014-01-01

    The snail Bithynia siamensis goniomphalos acts as the first intermediate host for the human liver fluke Opisthorchis viverrini, the major cause of cholangiocarcinoma (CCA) in Northeast Thailand. The undisputed link between CCA and O. viverrini infection has precipitated efforts to understand the molecular basis of host-parasite interactions with a view to ultimately developing new control strategies to combat this carcinogenic infection. To date most effort has focused on the interactions between the parasite and its human host, and little is known about the molecular relationships between the liver fluke and its snail intermediate host. In the present study we analyse the protein expression changes in different tissues of B. siamensis goniomphalos induced by infection with larval O. viverrini using iTRAQ labelling technology. We show that O. viverrini infection downregulates the expression of oxidoreductases and catalytic enzymes, while stress-related and motor proteins are upregulated. The present work could serve as a basis for future studies on the proteins implicated in the susceptibility/resistance of B. siamensis goniomphalos to O. viverrini, as well as studies on other pulmonate snail intermediate hosts of various parasitic flukes that infect humans. PMID:25284051

  6. Liver fluke (Fasciola hepatica) infection in cattle in Northern Ireland: a large-scale epidemiological investigation utilising surveillance data.

    PubMed

    Byrne, Andrew W; McBride, Stewart; Lahuerta-Marin, Angela; Guelbenzu, Maria; McNair, Jim; Skuce, Robin A; McDowell, Stanley W J

    2016-04-14

    Liver fluke (Fasciola hepatica) is a widespread parasite of ruminants which can have significant economic impact on cattle production. Fluke infection status at the animal-level is captured during meat inspection of all animals processed for human consumption within Northern Ireland. These national datasets have not been analysed to assess their utility in uncovering patterns in fluke infection at animal- and herd-levels in Northern Ireland. We utilised a dataset of 1.2 million animal records from ~18,000 herds across 3 years (2011-2013) to assess animal- and herd-level apparent prevalence and risk-factors associated with fluke infection. Animal-level apparent prevalence was measured as the proportion of animals exhibiting evidence of fluke infection at slaughter; between herd-level infection prevalence was measured by binary categorisation of herds (infected or not). "Within herd" infection prevalence was measured using the proportion of animals within a herd that showed evidence of fluke infection per year (ranging from 0-100%). "Within herd" infection prevalence at the herd level was investigated using multivariable modelling. At the animal level, the proportion of animals slaughtered that exhibited evidence of infection was 21-25% amongst years. Across herds, the proportion of herds with at least one infected animal, varied between 61 and 65%. However, there was a significant sampling effect at the herd-level; all herds where at least 105 animals slaughtered over the study period exhibited evidence of fluke infection (100%). There was significant variation in terms of within-herd infection prevalence. Risk factors included herd type, long-term weather variation, geographic location (region) and the abattoir. Liver fluke apparent prevalence was high at the herd-level across years. However, there was lower prevalence at the animal level, which may indicate significant variation in the exposure to fluke infection within herds. The proportion infected within

  7. Hope and exploitation.

    PubMed

    Martin, Adrienne M

    2008-01-01

    How do we encourage patients to be hopeful without exploiting their hope? A medical researcher or a pharmaceutical company can take unfair advantage of someone's hope by much subtler means than simply giving misinformation. Hope shapes deliberation, and therefore can make deliberation better or worse, by the deliberator's own standards of deliberation.

  8. Reducing the future threat from (liver) fluke: realistic prospect or quixotic fantasy?

    PubMed

    Fairweather, Ian

    2011-08-04

    The liver fluke remains an economically significant parasite of livestock and is emerging as an important zoonotic infection of humans. The incidence of the disease has increased in the last few years, as a possible consequence of changes to the World's climate. Future predictions suggest that this trend is likely to continue. Allied to the changing pattern of disease, reports of resistance to triclabendazole (TCBZ) have appeared in the literature, although they do not all represent genuine cases of resistance. Nevertheless, any reports of resistance are a concern, because triclabendazole is the only drug that has high activity against the migratory and damaging juvenile stages of infection. How to deal with the twin problems (of increasing incidence and drug resistance) is the overall theme of the session on "Trematodes: Fasciola hepatica epidemiology and control" and of this review to introduce the session. Greater knowledge of fluke epidemiology and population genetics will highlight those regions where surveillance is most required and indicate how quickly resistant populations of fluke may arise. Models of disease risk are becoming increasingly sophisticated and precise, with more refined data analysis programmes and Geographic Information Systems (GIS) data. Recent improvements have been made in our understanding of the action of triclabendazole and the ways in which flukes have become resistant to it. While microtubules are the most likely target for drug action, tubulin mutations do not seem to be involved in the resistance mechanism. Rather, upregulation of drug uptake and metabolism processes appear to be more important and the data relating to them will be discussed. The information may help in the design of new treatment strategies or pinpoint potential molecular markers for monitoring fluke populations. Advances in the identification of novel targets for drugs and vaccines will be made by the various "-omics" technologies that are now being applied to

  9. Cytosine methylation regulates oviposition in the pathogenic blood fluke Schistosoma mansoni

    PubMed Central

    Geyer, Kathrin K.; Rodríguez López, Carlos M.; Chalmers, Iain W.; Munshi, Sabrina E.; Truscott, Martha; Heald, James; Wilkinson, Mike J.; Hoffmann, Karl F.

    2011-01-01

    Similar to other metazoan pathogens, Schistosoma mansoni undergoes transcriptional and developmental regulation during its complex lifecycle and host interactions. DNA methylation as a mechanism to control these processes has, to date, been discounted in this parasite. Here we show the first evidence for cytosine methylation in the S. mansoni genome. Transcriptional coregulation of novel DNA methyltransferase (SmDnmt2) and methyl-CpG-binding domain proteins mirrors the detection of cytosine methylation abundance and implicates the presence of a functional DNA methylation machinery. Genome losses in cytosine methylation upon SmDnmt2 silencing and the identification of a hypermethylated, repetitive intron within a predicted forkhead gene confirm this assertion. Importantly, disruption of egg production and egg maturation by 5-azacytidine establishes an essential role for 5-methylcytosine in this parasite. These findings provide the first functional confirmation for this epigenetic modification in any worm species and link the cytosine methylation machinery to platyhelminth oviposition processes. PMID:21829186

  10. Identification of lead chemotherapeutic agents from medicinal plants against blood flukes and whipworms

    PubMed Central

    Wangchuk, Phurpa; Giacomin, Paul R.; Pearson, Mark S.; Smout, Michael J.; Loukas, Alex

    2016-01-01

    Schistosomiasis and trichuriasis are two of the most common neglected tropical diseases (NTD) that affect almost a billion people worldwide. There is only a limited number of effective drugs to combat these NTD. Medicinal plants are a viable source of parasiticides. In this study, we have investigated six of the 19 phytochemicals isolated from two Bhutanese medicinal plants, Corydalis crispa and Pleurospermum amabile, for their anthelmintic properties. We used the xWORM technique and Scanning Electron Microscope-based imaging to determine the activity of the compounds. Of the six compounds tested, isomyristicin and bergapten showed significant anthelmintic activity against Schistosoma mansoni and Trichuris muris with bergapten being the most efficacious compound one against both parasites (S. mansoni IC50 = 8.6 μg/mL and T. muris IC50 = 10.6 μg/mL) and also against the schistosomulum stage of S. mansoni. These two compounds induced tegumental damage to S. mansoni and affected the cuticle, bacillary bands and bacillary glands of T. muris. The efficacy against multiple phylogenetically distinct parasites and different life stages, especially the schistosomulum where praziquantel is ineffective, makes isomyristicin and bergapten novel scaffolds for broad-spectrum anthelmintic drug development that could be used for the control of helminths infecting humans and animals. PMID:27572696

  11. Haem uptake is essential for egg production in the haematophagous blood fluke of humans, Schistosoma mansoni.

    PubMed

    Toh, Shu Qin; Gobert, Geoffrey N; Malagón Martínez, David; Jones, Malcolm K

    2015-09-01

    Schistosomes ingest host erythrocytes, liberating large quantities of haem. Despite its toxicity, haem is an essential factor for numerous biological reactions, and may be an important iron source for these helminths. We used a fluorescence haem analogue, palladium mesoporphyrin, to investigate pathways of haem acquisition, and showed that palladium mesoporphyrin accumulates in the vitellaria (eggshell precursor glands) and ovary of female Schistosoma mansoni. Furthermore, incubation of adult females in 10-100 μm cyclosporin A (IC50 = 2.3 μm) inhibits the uptake of palladium mesoporphyrin to these tissues, with tenfold reductions in fluorescence intensity of the ovary. In vitro exposure to cyclosporin A resulted in significant perturbation of egg production, reducing egg output from 34 eggs per female to 5.7 eggs per female over the incubation period, and retardation of egg development. We characterized a S. mansoni homologue of the haem-responsive genes of Caenorhabditis elegans. The gene (Smhrg-1) encodes a protein with a molecular weight of approximately 17 kDa. SmHRG-1 was able to rescue growth in haem transport-deficient HEM1Δ yeast. Transcriptional suppression of Smhrg-1 in adult S. mansoni worms resulted in significant delay in egg maturation, with 47% of eggs from transcriptionally suppressed worms being identified as immature compared with only 27% of eggs laid by control worms treated with firefly luciferase. Our findings indicate the presence of transmembrane haem transporters in schistosomes, with a high abundance of these molecules being present in tissues involved in oogenesis.

  12. Morphological features of the nasal blood fluke Trichobilharzia regenti (Schistosomatidae, Digenea) from naturally infected hosts.

    PubMed

    Skírnisson, Karl; Kolářová, Libuse; Horák, Petr; Ferté, Hubert; Jouet, Damien

    2012-05-01

    The first author detected the nasal bird schistosome Trichobilharzia regenti in Iceland in Anas platyrhynchos in Landmannalaugar in autumn of 2003. Since then, measurements and morphological studies have been performed on fresh worms (fragments) obtained in the area from naturally infected ducks, A. platyrhynchos and Aythya marila. In the present study, we compare our findings to the original description of T. regenti by Horák et al. (Parasite 5:349-357, 1998) that relies upon worms obtained by experimental infections of A. platyrhynchos f. domestica and Cairina moschata f. domestica ducklings. Fragments obtained from naturally infected birds are markedly larger than those obtained in the experimental infection. Also, indistinct sex-related size difference was confirmed; males were more abundant in the material than females. Previously unknown morphological features detected in the present study include, e.g. subterminal spines on the oral sucker directed to the oral opening, spine pattern on the apical part of acetabulum and long tegumental spines (up to 16 μm) in the gonad and tail regions of both sexes. In males, we evaluated for the first time the morphology of the cirrus sac enclosing ejaculatory duct, prostata and the entire prostatic region, the course of vas deferens and the position of genital papilla. In females, the posterior part of the reproductive system was studied for the first time. The presence of the Laurer's canal was confirmed and its course from the oviduct to the surface, where spermatozoa were noticed to leave the canal, was described.

  13. Identification of lead chemotherapeutic agents from medicinal plants against blood flukes and whipworms.

    PubMed

    Wangchuk, Phurpa; Giacomin, Paul R; Pearson, Mark S; Smout, Michael J; Loukas, Alex

    2016-08-30

    Schistosomiasis and trichuriasis are two of the most common neglected tropical diseases (NTD) that affect almost a billion people worldwide. There is only a limited number of effective drugs to combat these NTD. Medicinal plants are a viable source of parasiticides. In this study, we have investigated six of the 19 phytochemicals isolated from two Bhutanese medicinal plants, Corydalis crispa and Pleurospermum amabile, for their anthelmintic properties. We used the xWORM technique and Scanning Electron Microscope-based imaging to determine the activity of the compounds. Of the six compounds tested, isomyristicin and bergapten showed significant anthelmintic activity against Schistosoma mansoni and Trichuris muris with bergapten being the most efficacious compound one against both parasites (S. mansoni IC50 = 8.6 μg/mL and T. muris IC50 = 10.6 μg/mL) and also against the schistosomulum stage of S. mansoni. These two compounds induced tegumental damage to S. mansoni and affected the cuticle, bacillary bands and bacillary glands of T. muris. The efficacy against multiple phylogenetically distinct parasites and different life stages, especially the schistosomulum where praziquantel is ineffective, makes isomyristicin and bergapten novel scaffolds for broad-spectrum anthelmintic drug development that could be used for the control of helminths infecting humans and animals.

  14. An expanding population of the giant liver fluke (Fascioloides magna) in elk (Cervus canadensis) and other ungulates in Canada.

    PubMed

    Pybus, Margo J; Butterworth, Eric W; Woods, John G

    2015-04-01

    Giant liver fluke (Fascioloides magna) populations readily expand under suitable conditions. Although extirpated from the eastern slopes of the Canadian Rocky Mountains in the early 1960s, the fluke reappeared following natural spread through mountain passes from British Columbia. Herein, we assessed epizootiology of the fluke population two decades later. Between 1984 and 1991, 534 ungulates, including 381 elk (Cervus canadensis), 68 mule deer (Odocoileus hemionus hemionus), 54 white-tailed deer (Odocoileus virginianus), and 31 moose (Alces alces) from adjacent areas of Alberta (AB) and British Columbia (BC), Canada, were examined for giant liver flukes. Prevalence in elk increased from 53% to 79% (1984-91) in Banff National Park (BNP) in AB and 77% to 100% (1985-89) in Kootenay National Park (KNP) in BC. Super-infections (>100 flukes) were more common in later years. Generally, prevalence increased over time and with increasing age of elk. Intensity was lowest in young-of-year (BNP 8±5, KNP 3), but similar in yearlings (BNP 36±11, KNP 23±8) and adults (BNP 33±5, KNP 32±6). Prevalence was similar in male and female elk. Intensity was higher in males (BNP 47±7, KNP 46±12) than in females (BNP 28±6, KNP 22±4), although the maximum number of flukes (545) occurred in a female elk. Prevalence and intensity differed among other species of ungulates but patterns were similar in each park. Prevalence was lower in mule deer (BNP 6%, KNP 4%) than in white-tailed deer (BNP 44%, KNP 28%) and moose (BNP 52%, KNP 63%). Intensity differed among these species but never exceeded 30 flukes. Gravid flukes occurred only in elk and white-tailed deer. Transmission occurred primarily in late summer-fall and in wet habitats. At least seven elk died as a direct result of fluke infection. In this region, elk and white-tailed deer maintain the F. magna population with spillover into moose and, rarely, mule deer.

  15. Prevalence, distribution and pathological significance of the bile fluke Pseudamphistomum truncatum in Eurasian otters (Lutra lutra) in Great Britain.

    PubMed

    Simpson, V R; Tomlinson, A J; Molenaar, F M

    2009-03-28

    Postmortem examinations on 160 otters found dead in Great Britain from 2005 to 2007 showed a high prevalence of infection with the bile fluke Pseudamphistomum truncatum in otters from Somerset and Dorset but no infection in otters from other areas, including Cornwall, the western half of Devon, north-east England and Scotland. Cases were also recorded for the first time in Gloucestershire and East Anglia. Eighteen of the 28 infected otters were male and no cubs were infected, but there was no significant correlation between infection status and sex or age. There was a strong positive correlation between bile fluke infection and gall bladder pathology. Thirty otters had thickened gall bladders resulting from hyperplasia of the epithelial and smooth muscle layers, fibrosis and infiltration by inflammatory cells and 19 of these were infected. No flukes were detected in the other 11 otters with abnormal gall bladders, possibly as a result of a successful immune response. The majority of otters with thickened gall bladders were in good physical condition but a positive association was not confirmed statistically. Fluke infection was also detected in nine of the 130 otters with apparently normal gall bladders. Liver pathology ranged from mild bile duct hyperplasia and periportal fibrosis to severe sclerosing cholangitis, hepatocyte necrosis and bile stasis. No otters were found to have died as a result of fluke infection, but there was a negative association, approaching significance, between infection and body condition.

  16. Resistance to liver fluke infection in the natural sheep host is correlated with a type-1 cytokine response.

    PubMed

    Pleasance, J; Wiedosari, E; Raadsma, H W; Meeusen, E; Piedrafita, D

    2011-09-01

    Indonesian thin-tail (ITT) sheep can resist infection with Fasciola gigantica but not F. hepatica and presents an ideal model to investigate the mechanisms of liver fluke resistance in a natural host. This study examines the local and systemic immune responses of sheep during Fasciola infection and demonstrates that different anatomical tissues display distinct cytokine profiles consistent with liver fluke migration. The study also reveals a significant difference in the cytokine and antibody profiles of ITT sheep infected with F. gigantica compared with F. hepatica, with a higher ratio of IL-4/IFN-γ mRNA expression and specific IgG1/IgG2 antibodies strongly correlating with pathology. Interestingly, the significant type-1 cytokine profile occurred in the lymph node closest to the site of infection at a time when the effective immune response against F. gigantica liver flukes is thought to occur. When the same F. gigantica infection in the resistant ITT sheep was compared with the susceptible Merino breed, the resistant type-1 phenotype against liver fluke infection was only observed in the ITT sheep. These studies provide the first evidence to suggest that the induction of an early type-1 immune response in this natural sheep host may be responsible for the ability to resist liver fluke infection. © 2011 Blackwell Publishing Ltd.

  17. GIS-based spatial statistical analysis of risk areas for liver flukes in Surin Province of Thailand.

    PubMed

    Rujirakul, Ratana; Ueng-arporn, Naporn; Kaewpitoon, Soraya; Loyd, Ryan J; Kaewthani, Sarochinee; Kaewpitoon, Natthawut

    2015-01-01

    It is urgently necessary to be aware of the distribution and risk areas of liver fluke, Opisthorchis viverrini, for proper allocation of prevention and control measures. This study aimed to investigate the human behavior, and environmental factors influencing the distribution in Surin Province of Thailand, and to build a model using stepwise multiple regression analysis with a geographic information system (GIS) on environment and climate data. The relationship between the human behavior, attitudes (<50%; X111), environmental factors like population density (148-169 pop/km2; X73), and land use as wetland (X64), were correlated with the liver fluke disease distribution at 0.000, 0.034, and 0.006 levels, respectively. Multiple regression analysis, by equations OV=-0.599+0.005(population density (148-169 pop/km2); X73)+0.040 (human attitude (<50%); X111)+0.022 (land used (wetland; X64), was used to predict the distribution of liver fluke. OV is the patients of liver fluke infection, R Square=0.878, and, Adjust R Square=0.849. By GIS analysis, we found Si Narong, Sangkha, Phanom Dong Rak, Mueang Surin, Non Narai, Samrong Thap, Chumphon Buri, and Rattanaburi to have the highest distributions in Surin province. In conclusion, the combination of GIS and statistical analysis can help simulate the spatial distribution and risk areas of liver fluke, and thus may be an important tool for future planning of prevention and control measures.

  18. Dicrocoelium chinensis and Dicrocoelium dendriticum (Trematoda: Digenea) are distinct lancet fluke species based on mitochondrial and nuclear ribosomal DNA sequences.

    PubMed

    Liu, Guo-Hua; Yan, Hong-Bin; Otranto, Domenico; Wang, Xing-Ye; Zhao, Guang-Hui; Jia, Wan-Zhong; Zhu, Xing-Quan

    2014-10-01

    Lancet flukes parasitize the bile ducts and gall bladder of a range of mammals, including humans, causing dicrocoeliosis. In the present study, we sequenced and characterized the complete mitochondrial (mt) genomes as well as the first and second internal transcribed spacers (ITS-1 and ITS-2=ITS) of nuclear ribosomal DNA (rDNA) of two lancet flukes, Dicrocoelium chinensis and D. dendriticum. Sequence comparison of a conserved mt gene and nuclear rDNA sequences among multiple individual lancet flukes revealed substantial nucleotide differences between the species but limited sequence variation within each of them. Phylogenetic analysis of the concatenated amino acid and multiple mt rrnS sequences using Bayesian inference supported the separation of D. chinensis and D. dendriticum into two distinct species-specific clades. Results of the present study support the proposal that D. dendriticum and D. chinensis represent two distinct lancet flukes. While providing the first mt genomes from members of the superfamily Plagiorchioidea, the novel mt markers described herein will be useful for further studies of the diagnosis, epidemiology and systematics of the lancet flukes and other trematodes of human and animal health significance.

  19. Multisensor staring exploitation

    NASA Astrophysics Data System (ADS)

    Bryant, Michael L.

    2008-04-01

    The focus of this paper is on the exploitation of new staring sensors to address the urban surveillance challenge and help combat the war on terror. A staring sensor visualization environment, known as the Data Table, will be presented which integrates staring sensors with close-in sensors, such as small UAVs, building mounted sensors, and unattended ground sensors (UGS). There are several staring sensors in development, but two in particular will be highlighted in this paper - NightStare and the Gotcha Radar, both under development by the Air Force Research Laboratory (AFRL).

  20. Cathepsin F Cysteine Protease of the Human Liver Fluke, Opisthorchis viverrini

    PubMed Central

    Laha, Thewarach; Sripa, Banchob; Kaewkes, Sasithorn; Morales, Maria E.; Mann, Victoria H.; Parriott, Sandi K.; Suttiprapa, Sutas; Robinson, Mark W.; To, Joyce; Dalton, John P.; Loukas, Alex; Brindley, Paul J.

    2009-01-01

    Background The liver fluke Opisthorchis viverrini is classified as a class I carcinogen due to the association between cholangiocarcinoma and chronic O. viverrini infection. During its feeding activity within the bile duct, the parasite secretes several cathepsin F cysteine proteases that may induce or contribute to the pathologies associated with hepatobiliary abnormalities. Methodology/Principal Findings Here, we describe the cDNA, gene organization, phylogenetic relationships, immunolocalization, and functional characterization of the cathepsin F cysteine protease gene, here termed Ov-cf-1, from O. viverrini. The full length mRNA of 1020 nucleotides (nt) encoded a 326 amino acid zymogen consisting of a predicted signal peptide (18 amino acids, aa), prosegment (95 aa), and mature protease (213 aa). BLAST analysis using the Ov-CF-1 protein as the query revealed that the protease shared identity with cathepsin F-like cysteine proteases of other trematodes, including Clonorchis sinensis (81%), Paragonimus westermani (58%), Schistosoma mansoni and S. japonicum (52%), and with vertebrate cathepsin F (51%). Transcripts encoding the protease were detected in all developmental stages that parasitize the mammalian host. The Ov-cf-1 gene, of ∼3 kb in length, included seven exons interrupted by six introns; the exons ranged from 69 to 267 bp in length, the introns from 43 to 1,060 bp. The six intron/exon boundaries of Ov-cf-1 were conserved with intron/exon boundaries in the human cathepsin F gene, although the gene structure of human cathepsin F is more complex. Unlike Ov-CF-1, human cathepsin F zymogen includes a cystatin domain in the prosegment region. Phylogenetic analysis revealed that the fluke, human, and other cathepsin Fs branched together in a clade discrete from the cathepsin L cysteine proteases. A recombinant Ov-CF-1 zymogen that displayed low-level activity was expressed in the yeast Pichia pastoris. Although the recombinant protease did not

  1. Raw fish consumption in liver fluke endemic areas in rural southern Laos.

    PubMed

    Xayaseng, Vilavanh; Phongluxa, Khampheng; van Eeuwijk, Peter; Akkhavong, Kongsap; Odermatt, Peter

    2013-08-01

    Consumption of raw or insufficiently cooked fish is a major public health concern in Southeast Asia, and in Lao People's Democratic Republic (Lao PDR), in particular. We aimed to assess the knowledge, attitudes, perceptions and practices of villagers in liver fluke endemic areas related to raw fish preparation, consumption and its health consequences. In February 2010, eight focus group discussions (FGDs, 35 men and 37 women total) and direct observations were conducted in four randomly selected villages in Saravane District, Saravane Province (Lao PDR). FGDs distilled the knowledge, attitudes, perceptions and practices of adult community members on raw fish preparation, consumption and its consequences for health. Conversations were transcribed from notes and tape-recorders. MaxQDA software was used for content analysis. Knowledge regarding the health effects of raw fish consumption was heterogeneous. Some participants did not associate liver fluke infection with any ill health, while others linked it to digestive problems. Participants also associated vegetables and tree leave consumption with liver fluke infection. The majority of FGD participants considered fish flesh that had been prepared with weaver ant extract to be safe for consumption. Visual appearance, taste, smell and personal preference were given as reasons for consuming raw fish dishes. Moreover, participants considered it a traditional way of food preparation, practiced for generations in Laos. Ten different fish dishes that use raw or fermented fish were identified. All FGD participants reported consuming dishes with raw fish. This study reveals a low degree of knowledge among local people on the health risks related to frequent consumption of raw or insufficiently cooked fish. Fish dishes were considered to be 'well-prepared' (that is, 'cooked') even though the fish had not been heated. In future, successful health education campaigns will have to address the specific knowledge, attitudes

  2. Proteomic profile of Bithynia siamensis goniomphalos snails upon infection with the carcinogenic liver fluke Opisthorchis viverrini.

    PubMed

    Prasopdee, Sattrachai; Tesana, Smarn; Cantacessi, Cinzia; Laha, Thewarach; Mulvenna, Jason; Grams, Rudi; Loukas, Alex; Sotillo, Javier

    2015-01-15

    The snail Bithynia siamensis goniomphalos acts as the first intermediate host for the human liver fluke Opisthorchis viverrini, the major cause of cholangiocarcinoma (CCA) in Northeast Thailand. The undisputed link between CCA and O. viverrini infection has precipitated efforts to understand the molecular basis of host-parasite interactions with a view to ultimately developing new control strategies to combat this carcinogenic infection. To date most effort has focused on the interactions between the parasite and its human host, and little is known about the molecular relationships between the liver fluke and its snail intermediate host. In the present study we analyse the protein expression changes in different tissues of B. siamensis goniomphalos induced by infection with larval O. viverrini using iTRAQ labelling technology. We show that O. viverrini infection downregulates the expression of oxidoreductases and catalytic enzymes, while stress-related and motor proteins are upregulated. The present work could serve as a basis for future studies on the proteins implicated in the susceptibility/resistance of B. siamensis goniomphalos to O. viverrini, as well as studies on other pulmonate snail intermediate hosts of various parasitic flukes that infect humans. Despite the importance and high prevalence of opisthorchiasis in some regions of Southeast Asia and the direct relationship between infection by Opisthorchis viverrini and the incidence of cholangiocarcinoma, little is known of the modifications induced by this parasite in its snail intermediate hosts. This time-course study provides the first in-depth quantitative proteomic analysis of experimentally infected Bithynia siamensis goniomphalos. We show how motor and stress-related proteins are upregulated in infected snails, while O. viverrini infection downregulates the expression of oxidoreductases and catalytic enzymes. This work serves as a basis for the development of new strategies, focused on the

  3. The carcinogenic liver fluke Opisthorchis viverrini is a reservoir for species of Helicobacter.

    PubMed

    Deenonpoe, Raksawan; Chomvarin, Chariya; Pairojkul, Chawalit; Chamgramol, Yaowalux; Loukas, Alex; Brindley, Paul J; Sripa, Banchob

    2015-01-01

    There has been a strong, positive correlation between opisthorchiasis-associated cholangiocarcinoma and infection with Helicobacter. Here a rodent model of human infection with Opisthorchis viverrini was utilized to further investigate relationships of apparent co-infections with O. viverrini and H. pylori. A total of 150 hamsters were assigned to five groups: i) Control hamsters not infected with O. viverrini; ii) O. viverrini-infected hamsters; iii) non-O. viverrini infected hamsters treated with antibiotics (ABx); iv) O. viverrini-infected hamsters treated with ABx; and v) O. viverrini-infected hamsters treated both with ABx and praziquantel (PZQ). Stomach, gallbladder, liver, colonic tissue, colorectal feces and O. viverrini worms were collected and the presence of species of Helicobacter determined by PCR-based approaches. In addition, O. viverrini worms were cultured in vitro with and without ABx for four weeks, after which the presence of Helicobacter spp. was determined. In situ localization of H. pylori and Helicobacter-like species was performed using a combination of histochemistry and immunohistochemistry. The prevalence of H. pylori infection in O. viverrini-infected hamsters was significantly higher than that of O. viverrini-uninfected hamsters (p≤0.001). Interestingly, O. viverrini-infected hamsters treated with ABx and PZQ (to remove the flukes) had a significantly lower frequency of H. pylori than either O. viverrini- infected hamsters treated only with ABx or O. viverrini-infected hamsters, respectively (p≤0.001). Quantitative RT-PCR strongly confirmed the correlation between intensity H. pylori infection and the presence of liver fluke infection. In vitro, H. pylori could be detected in the O. viverrini worms cultured with ABx over four weeks. In situ localization revealed H. pylori and other Helicobacter-like bacteria in worm gut. The findings indicate that the liver fluke O. viverrini in the biliary tree of the hamsters harbors H. pylori

  4. Functional Analysis of the Unique Cytochrome P450 of the Liver Fluke Opisthorchis felineus.

    PubMed

    Pakharukova, Mariya Y; Vavilin, Valentin A; Sripa, Banchob; Laha, Thewarach; Brindley, Paul J; Mordvinov, Viatcheslav A

    2015-12-01

    The basic metabolic cytochrome P450 (CYP) system is essential for biotransformation of sterols and xenobiotics including drugs, for synthesis and degradation of signaling molecules in all living organisms. Most eukaryotes including free-living flatworms have numerous paralogues of the CYP gene encoding heme monooxygenases with specific substrate range. Notably, by contrast, the parasitic flatworms have only one CYP gene. The role of this enzyme in the physiology and biochemistry of helminths is not known. The flukes and tapeworms are the etiologic agents of major neglected tropical diseases of humanity. Three helminth infections (Opisthorchis viverrini, Clonorchis sinensis and Schistosoma haematobium) are considered by the International Agency for Research on Cancer (IARC) as definite causes of cancer. We focused our research on the human liver fluke Opisthorchis felineus, an emerging source of biliary tract disease including bile duct cancer in Russia and central Europe. The aims of this study were (i) to determine the significance of the CYP activity for the morphology and survival of the liver fluke, (ii) to assess CYP ability to metabolize xenobiotics, and (iii) to localize the CYP activity in O. felineus tissues. We observed high constitutive expression of CYP mRNA (Real-time PCR) in O. felineus. This enzyme metabolized xenobiotics selective for mammalian CYP2E1, CYP2B, CYP3A, but not CYP1A, as determined by liquid chromatography and imaging analyses. Tissue localization studies revealed the CYP activity in excretory channels, while suppression of CYP mRNA by RNA interference was accompanied by morphological changes of the excretory system and increased mortality rates of the worms. These results suggest that the CYP function is linked to worm metabolism and detoxification. The findings also suggest that the CYP enzyme is involved in vitally important processes in the organism of parasites and is a potential drug target.

  5. Functional Analysis of the Unique Cytochrome P450 of the Liver Fluke Opisthorchis felineus

    PubMed Central

    Pakharukova, Mariya Y.; Vavilin, Valentin A.; Sripa, Banchob; Laha, Thewarach; Brindley, Paul J.; Mordvinov, Viatcheslav A.

    2015-01-01

    The basic metabolic cytochrome P450 (CYP) system is essential for biotransformation of sterols and xenobiotics including drugs, for synthesis and degradation of signaling molecules in all living organisms. Most eukaryotes including free-living flatworms have numerous paralogues of the CYP gene encoding heme monooxygenases with specific substrate range. Notably, by contrast, the parasitic flatworms have only one CYP gene. The role of this enzyme in the physiology and biochemistry of helminths is not known. The flukes and tapeworms are the etiologic agents of major neglected tropical diseases of humanity. Three helminth infections (Opisthorchis viverrini, Clonorchis sinensis and Schistosoma haematobium) are considered by the International Agency for Research on Cancer (IARC) as definite causes of cancer. We focused our research on the human liver fluke Opisthorchis felineus, an emerging source of biliary tract disease including bile duct cancer in Russia and central Europe. The aims of this study were (i) to determine the significance of the CYP activity for the morphology and survival of the liver fluke, (ii) to assess CYP ability to metabolize xenobiotics, and (iii) to localize the CYP activity in O. felineus tissues. We observed high constitutive expression of CYP mRNA (Real-time PCR) in O. felineus. This enzyme metabolized xenobiotics selective for mammalian CYP2E1, CYP2B, CYP3A, but not CYP1A, as determined by liquid chromatography and imaging analyses. Tissue localization studies revealed the CYP activity in excretory channels, while suppression of CYP mRNA by RNA interference was accompanied by morphological changes of the excretory system and increased mortality rates of the worms. These results suggest that the CYP function is linked to worm metabolism and detoxification. The findings also suggest that the CYP enzyme is involved in vitally important processes in the organism of parasites and is a potential drug target. PMID:26625139

  6. Evaluation of the comparative efficacy of a moxidectin plus triclabendazole pour-on solution against adult and immature liver fluke, Fasciola hepatica, in cattle.

    PubMed

    Geurden, Thomas; Bartram, David; Van Brussel, Leen; Bo, Liu; Scott-Baird, Emer; Rugg, Douglas

    2012-10-26

    The objective of this study was to evaluate the efficacy of a pour-on solution containing moxidectin plus triclabendazole (MOX plus TCBZ) against immature and adult stages of the liver fluke in cattle and compare the efficacy with other commercially available preparations. To this end, 104 male Holstein-Friesian calves aged between 3 and 4 months, were randomly allocated to 13 groups of eight animals each, and infected with approximately 500 Fasciola hepatica metacercariae. One group remained untreated, four groups were treated with MOX plus TCBZ at a dose rate of 0.1 mL/kg, four other groups were treated with ivermectin (IVM) plus clorsulon injectable at a dose rate of 0.02 mL/kg, and the remaining four groups were treated with IVM plus closantel pour-on at a dose rate of 0.1 mL/kg. Each treatment was applied to one of the groups at 4 weeks, 6 weeks, 8 weeks and 12 weeks after the experimental infection. At necropsy (99-102 days after infection), all untreated animals were infected with a minimum of 30 flukes. The MOX plus TCBZ treated animals had significantly (P<0.0001) lower fluke counts compared to the untreated control animals at all time points after treatment. Efficacy against 8-week old and adult flukes was >99.5%. For 6-week old immature fluke, the efficacy was 98.0% and for 4-week old immature fluke the efficacy was 90.9%. The IVM plus closantel pour-on treated animals had significantly lower fluke counts compared to the untreated control animals for adult and 8-week old flukes (P<0.0001), and for 6-week old flukes (P=0.002). The efficacy was 26.8%, 68.2%, 90.6% and 99.3% against 4-week, 6-week and 8-week old immature flukes, and adult flukes respectively. The IVM plus clorsulon treated animals had significantly lower fluke counts compared to the untreated control animals for adult (P<0.0001) and 8-week old (P<0.05) flukes. The efficacy was 29.7%, 43.4%, 53.2% and 99.2% against 4-week, 6-week and 8-week old immature flukes, and adult flukes respectively

  7. A comparison of the efficacy of doramectin, closantel and levamisole in the treatment of the 'oriental eye fluke', Philophthalmus gralli, in commercially reared ostriches (Struthio camelus).

    PubMed

    Mukaratirwa, S; Chimbwanda, M; Matekwe, N; Matenga, E

    2008-06-01

    Commercially reared ostriches at Msengi farm situated in the Chinhoyi area of Mashonaland West province in Zimbabwe were found to be infected with the 'oriental eye fluke', Philopthalmus gralli, in 2001. This was the ist record of the fluke in Zimbabwe. Trials were conducted to identify a suitable drug for the treatment of this fluke. A total of 12 ostriches confirmed to be infected with the fluke through clinical examination of the eyes and identification of the fluke were randomly divided into 3 equal groups, with each group receiving a different treatment protocol. The 3 drugs used were doramectin, levamisole and closantel. Each of the drugs was used in combination with chloramphenicol as an eye ointment. Levamisole was administered topically into the eye whereas doramectin and closantel were administered parenterally as an intramuscular injection. The results indicated a positive response in levamisole-treated birds but there were no noticeable responses to doramectin and closantel treatments.

  8. [Studies on the molluscicidal and cercariacidal effects of various pesticides in liver fluke

    PubMed

    Kim, Jung Man

    1965-12-01

    Clonorchiasis for which no specific therapy is available has been recognized as one of the serious public health problems in terms of waste of human productivity in Korea today and an urgent consideration must be given to its prevention and control. For past several years, the author has been finding that the infection rate of liver fluke in fish from the Kum-Ho river which has long been recognized as the world's notorious prevalent area of the disease, has been decreasing gradually. Here the author formulated the hypothesis that the decreasing of infection rate might be influenced by the common use of pesticide in plants along the river. Basing this hypothesis, the effective use of pesticide may contribute to the control of the disease by cutting the life cycle of liver fluke. To test above hypothesis, molluscicidal effect on Parafossarulus manchouricus and cercariacidal effect of various pesticides in liver fluke have been determined and the following results were obtained. 1. In molluscicidal effect, the most potent agent in low concentration was Bayer 73 which is 3 to 70 times stronger than other pesticides. When compared with NaPCP which has been widely used for the eradication of Onchomelania, Bayer 73 shows 5 to 10 times stronger effect. The order of pesticide in molluscicidal effect was: Bayer 73, Nicotin, NaPCP, Sevin, Parathion, Copper sulfate and Lindane. 2. In cercariacidal effect, the most potent agent was Parathion which had 2 to 5 times stronger effect than Bayer 73 or NaPCP. The order of pesticide in the cercariacidal effect was: Parathion, Bayer73, NaPCP, Lindane, Nicotin,Sevin, and Copper sulfate. 3. By applying the common used concentration of pesticides considering the toxicity to plants, Bayer 73 is most potent in molluscicidal effect and then Nicotin, NaPCP, Copper sulfate, Sevin, Parathion and Lindane in order. In cercariacidal effect, Parathion is the most potent and NaPCP, Bayer 73, Lindane, and Copper sulfate are followed. 4. Considering

  9. Fasciola hepatica: Histological changes in the somatic and reproductive tissues of liver fluke following closantel treatment of experimentally-infected sheep.

    PubMed

    Scarcella, S; Hanna, R E B; Brennan, G P; Solana, H; Fairweather, I

    2016-01-15

    Lambs infected with the Cullompton isolate of Fasciola hepatica were treated orally or subcutaneously with 10mg/kg of closantel at 16 weeks post-infection. Adult flukes were recovered from the liver of individual animals at 12h, 24h, or 36h post-treatment. The flukes were processed for histological analysis. In general, degenerative changes in the reproductive and somatic tissues were progressive, and were most marked in flukes exposed to closantel in vivo for 36h. However, flukes from a 12h subcutaneously-treated lamb showed marked deterioration of the testis, possibly because a portion of the dose has been delivered intravenously. Fewer intact eggs were seen in the uterus of flukes exposed to closantel for longer times (whether administered subcutaneously or orally to the host). The most conspicuous closantel-induced effect in flukes from treated hosts was progressive damage to the tegumental syncytium. While the flukes from 24h-treated hosts showed relatively minor damage to limited areas of the syncytium, towards the posterior end, the flukes from 36h-treated hosts (and flukes from the lamb that putatively received intravenous dosage) had lost large areas of the surface syncytium from the posterior end and dorsal surface, although the syncytium over the anterior end and the anterior ventral surface was largely spared. In areas where the syncytium had sloughed, the underlying structures such as the vitelline follicles, gut profiles and testis profiles, showed marked degeneration and breakdown. Other changes included cell depletion and early stage apoptosis in the testis, ovary and vitelline follicles. This study establishes a model for histological changes in closantel-sensitive F. hepatica exposed to closantel in vivo. Histopathological studies could be complementary to the efficacy controlled test for for closantel resistance in fluke populations.

  10. The Geohazards Exploitation Platform

    NASA Astrophysics Data System (ADS)

    Laur, Henri; Casu, Francesco; Bally, Philippe; Caumont, Hervé; Pinto, Salvatore

    2016-04-01

    The Geohazards Exploitation Platform, or Geohazards TEP (GEP), is an ESA originated R&D activity of the EO ground segment to demonstrate the benefit of new technologies for large scale processing of EO data. This encompasses on-demand processing for specific user needs, systematic processing to address common information needs of the geohazards community, and integration of newly developed processors for scientists and other expert users. The platform supports the geohazards community's objectives as defined in the context of the International Forum on Satellite EO and Geohazards organised by ESA and GEO in Santorini in 2012. The GEP is a follow on to the Supersites Exploitation Platform (SSEP) an ESA initiative to support the Geohazards Supersites & Natural Laboratories initiative (GSNL). Today the GEP allows to exploit 70+ Terabyte of ERS and ENVISAT archive and the Copernicus Sentinel-1 data available on line. The platform has already engaged 22 European early adopters in a validation activity initiated in March 2015. Since September, this validation has reached 29 single user projects. Each project is concerned with either integrating an application, running on demand processing or systematically generating a product collection using an application available in the platform. The users primarily include 15 geoscience centres and universities based in Europe: British Geological Survey (UK), University of Leeds (UK), University College London (UK), ETH University of Zurich (CH), INGV (IT), CNR-IREA and CNR-IRPI (IT), University of L'Aquila (IT), NOA (GR), Univ. Blaise Pascal & CNRS (FR), Ecole Normale Supérieure (FR), ISTERRE / University of Grenoble-Alpes (FR). In addition, there are users from Africa and North America with the University of Rabat (MA) and the University of Miami (US). Furthermore two space agencies and four private companies are involved: the German Space Research Centre DLR (DE), the European Space Agency (ESA), Altamira Information (ES

  11. Image exploitation for MISAR

    NASA Astrophysics Data System (ADS)

    Heinze, N.; Edrich, M.; Saur, G.; Krüger, W.

    2007-04-01

    The miniature SAR-system MiSAR has been developed by EADS Germany for lightweight UAVs like the LUNASystem. MiSAR adds to these tactical UAV-systems the all-weather reconnaissance capability, which is missing until now. Unlike other SAR sensors, that produce large strip maps at update rates of several seconds, MiSAR generates sequences of SAR images with approximately 1 Hz frame rate. photo interpreters (PI) of tactical drones, now mainly experienced with visual interpretation, are not used to SARimages, especially not with SAR-image sequence characteristics. So they should be supported to improve their ability to carry out their task with a new, demanding sensor system. We have therefore analyzed and discussed with military PIs in which task MiSAR can be used and how the PIs can be supported by special algorithms. We developed image processing- and exploitation-algorithms for such SAR-image sequences. A main component is the generation of image sequence mosaics to get more oversight. This mosaicing has the advantage that also non straight /linear flight-paths and varying squint angles can be processed. Another component is a screening-component for manmade objects to mark regions of interest in the image sequences. We use a classification based approach, which can be easily adapted to new sensors and scenes. These algorithms are integrated into an image exploitation system to improve the image interpreters ability to get a better oversight, better orientation and helping them to detect relevant objects, especially considering long endurance reconnaissance missions.

  12. Bovine and ovine rumen fluke in Ireland-Prevalence, risk factors and species identity based on passive veterinary surveillance and abattoir findings.

    PubMed

    Toolan, Dónal P; Mitchell, Gillian; Searle, Kate; Sheehan, Maresa; Skuce, Philip J; Zadoks, Ruth N

    2015-09-15

    The prevalence of rumen fluke, the incidence of clinical paramphistomosis and the trematode's species identity were studied in cattle and sheep in the Republic of Ireland using passive veterinary surveillance (faecal examination and necropsy results; 2010-2013) and abattoir data. Based on faecal examination, the prevalence of rumen fluke was higher in cattle than in sheep. Rumen fluke prevalence in cattle and sheep fluctuated over the year and in most years (2011-2013), prevalence was higher in winter (December-February) than in summer (June-August). For 3 of 4 years studied, there was no correlation between monthly prevalence of rumen fluke and prevalence of liver fluke as estimated by faecal examination. At sample level, joint occurrence of rumen fluke and liver fluke was 1.1-2.0 times more common than would be expected under the assumption of independence. Based on necropsy data, a spike in deaths attributed to paramphistomosis was observed in 2012, when rainfall was unusually high. This spike in mortality was not accompanied by a spike in faecal prevalence, emphasizing that the incidence of disease, which is due to high burdens of juvenile rumen fluke in the gut, is not correlated with prevalence of infection, which is measured by faecal examination and reflects presence of adult fluke in the rumen. At slaughter, 52% of 518 cattle from 101 herds were positive for rumen fluke, compared to 14% of 158 sheep. Prevalence in cattle was higher than reported in most studies from mainland Europe and varied by animal category, age, sex, abattoir visit and location (county) of farm from which the animal was submitted for slaughter, but in multivariate analysis, only sampling month and county were significantly associated with detection of rumen fluke. The identity of rumen fluke in cattle and sheep was confirmed as Calicophoron daubneyi. Although C. daubneyi is thought to share an intermediate host snail with Fasciola hepatica, the differences in prevalence between host

  13. Clonorchis sinensis, an oriental liver fluke, as a human biological agent of cholangiocarcinoma: a brief review.

    PubMed

    Kim, Tong-Soo; Pak, Jhang Ho; Kim, Jong-Bo; Bahk, Young Yil

    2016-11-01

    Parasitic diseases remain an unarguable public health problem worldwide. Liver fluke Clonorchis sinensis is a high risk pathogenic parasitic helminth which is endemic predominantly in Asian countries, including Korea, China, Taiwan, Vietnam, and the far eastern parts of Russia, and is still actively transmitted. According to the earlier 8th National Survey on the Prevalence of Intestinal Parasitic Infections in 2012, C. sinensis was revealed as the parasite with highest prevalence of 1.86% in general population among all parasite species surveyed in Korea. This fluke is now classified under one of the definite Group 1 human biological agents (carcinogens) by International Agency of Research on Cancer (IARC) along with two other parasites, Opisthorchis viverrini and Schistosoma haematobium. C. sinensis infestation is mainly linked to liver and biliary disorders, especially cholangiocarcinoma (CCA). For the purposes of this mini-review, we will only focus on C. sinensis and review pathogenesis and carcinogenesis of clonorchiasis, disease condition by C. sinensis infestation, and association between C. sinensis infestation and CCA. In this presentation, we briefly consider the current scientific status for progression of CCA by heavy C. sinensis infestation from the food-borne trematode and development of CCA. [BMB Reports 2016; 49(11): 590-597].

  14. Carcinogenic Liver Fluke Secretes Extracellular Vesicles That Promote Cholangiocytes to Adopt a Tumorigenic Phenotype.

    PubMed

    Chaiyadet, Sujittra; Sotillo, Javier; Smout, Michael; Cantacessi, Cinzia; Jones, Malcolm K; Johnson, Michael S; Turnbull, Lynne; Whitchurch, Cynthia B; Potriquet, Jeremy; Laohaviroj, Marut; Mulvenna, Jason; Brindley, Paul J; Bethony, Jeffrey M; Laha, Thewarach; Sripa, Banchob; Loukas, Alex

    2015-11-15

    Throughout Asia, there is an unprecedented link between cholangiocarcinoma and infection with the liver fluke Opisthorchis viverrini. Multiple processes, including chronic inflammation and secretion of parasite proteins into the biliary epithelium, drive infection toward cancer. Until now, the mechanism and effects of parasite protein entry into cholangiocytes was unknown. Various microscopy techniques were used to identify O. viverrini extracellular vesicles (EVs) and their internalization by human cholangiocytes. Using mass spectrometry we characterized the EV proteome and associated changes in cholangiocytes after EV uptake, and we detected EV proteins in bile of infected hamsters and humans. Cholangiocyte proliferation and interleukin 6 (IL-6) secretion was measured to assess the impact of EV internalization. EVs were identified in fluke culture medium and bile specimens from infected hosts. EVs internalized by cholangiocytes drove cell proliferation and IL-6 secretion and induced changes in protein expression associated with endocytosis, wound repair, and cancer. Antibodies to an O. viverrini tetraspanin blocked EV uptake and IL-6 secretion by cholangiocytes. This is the first time that EVs from a multicellular pathogen have been identified in host tissues. Our findings imply a role for O. viverrini EVs in pathogenesis and highlight an approach to vaccine development for this infectious cancer. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America.

  15. Clonorchis sinensis, an oriental liver fluke, as a human biological agent of cholangiocarcinoma: a brief review

    PubMed Central

    Kim, Tong-Soo; Pak, Jhang Ho; Kim, Jong-Bo; Bahk, Young Yil

    2016-01-01

    Parasitic diseases remain an unarguable public health problem worldwide. Liver fluke Clonorchis sinensis is a high risk pathogenic parasitic helminth which is endemic predominantly in Asian countries, including Korea, China, Taiwan, Vietnam, and the far eastern parts of Russia, and is still actively transmitted. According to the earlier 8th National Survey on the Prevalence of Intestinal Parasitic Infections in 2012, C. sinensis was revealed as the parasite with highest prevalence of 1.86% in general population among all parasite species surveyed in Korea. This fluke is now classified under one of the definite Group 1 human biological agents (carcinogens) by International Agency of Research on Cancer (IARC) along with two other parasites, Opisthorchis viverrini and Schistosoma haematobium. C. sinensis infestation is mainly linked to liver and biliary disorders, especially cholangiocarcinoma (CCA). For the purposes of this mini-review, we will only focus on C. sinensis and review pathogenesis and carcinogenesis of clonorchiasis, disease condition by C. sinensis infestation, and association between C. sinensis infestation and CCA. In this presentation, we briefly consider the current scientific status for progression of CCA by heavy C. sinensis infestation from the food-borne trematode and development of CCA. PMID:27418285

  16. Risk biomarkers for assessment and chemoprevention of liver fluke-associated cholangiocarcinoma.

    PubMed

    Yongvanit, Puangrat; Pinlaor, Somchai; Loilome, Watcharin

    2014-05-01

    Human liver fluke, Opisthorchis viverrini (Ov), is the major risk factor of cholangiocarcinoma (CCA) in northeastern Thailand. Our approach focuses on genetic progression and molecular changes in the carcinogenic pathway of liver fluke-associated CCA aimed at assessing patients at risk of CCA and using chemoprevention as the secondary cancer prevention to reduce the incidence of CCA. This review summarizes altered gene expressions, biomolecules and their modification, i.e. DNA adducts, oxidized proteins, oxysterols and fibrotic markers in hamster- and human-CCA. Potential risk biomarker(s) and chemopreventive agent(s) criteria and selection were based on results from experimental and epidemiological studies identifying hepatobiliary disease, including CCA. Laboratory results reveal that oxidative stress induced by Ov infection leads to bimolecular damage, tissue remodeling especially periductal fibrosis and alteration of gene expressions, which could be involved in all steps of CCA carcinogenesis. Some of these molecules are reported to change their levels in opisthorchiasis, periductal fibrosis diagnosed by ultrasonography and CCA. Chemoprevention in experimental CCA tumorigenesis is discussed. These multiple risk biomarkers could now be explored for screening including chemopreventive intervention of subjects living in endemic areas where the prevalence of opisthorchiasis remains high. © 2014 Japanese Society of Hepato-Biliary-Pancreatic Surgery.

  17. Carcinogenic Liver Fluke Secretes Extracellular Vesicles That Promote Cholangiocytes to Adopt a Tumorigenic Phenotype

    PubMed Central

    Chaiyadet, Sujittra; Sotillo, Javier; Smout, Michael; Cantacessi, Cinzia; Jones, Malcolm K.; Johnson, Michael S.; Turnbull, Lynne; Whitchurch, Cynthia B.; Potriquet, Jeremy; Laohaviroj, Marut; Mulvenna, Jason; Brindley, Paul J.; Bethony, Jeffrey M.; Laha, Thewarach; Sripa, Banchob; Loukas, Alex

    2015-01-01

    Background. Throughout Asia, there is an unprecedented link between cholangiocarcinoma and infection with the liver fluke Opisthorchis viverrini. Multiple processes, including chronic inflammation and secretion of parasite proteins into the biliary epithelium, drive infection toward cancer. Until now, the mechanism and effects of parasite protein entry into cholangiocytes was unknown. Methods. Various microscopy techniques were used to identify O. viverrini extracellular vesicles (EVs) and their internalization by human cholangiocytes. Using mass spectrometry we characterized the EV proteome and associated changes in cholangiocytes after EV uptake, and we detected EV proteins in bile of infected hamsters and humans. Cholangiocyte proliferation and interleukin 6 (IL-6) secretion was measured to assess the impact of EV internalization. Results. EVs were identified in fluke culture medium and bile specimens from infected hosts. EVs internalized by cholangiocytes drove cell proliferation and IL-6 secretion and induced changes in protein expression associated with endocytosis, wound repair, and cancer. Antibodies to an O. viverrini tetraspanin blocked EV uptake and IL-6 secretion by cholangiocytes. Conclusions. This is the first time that EVs from a multicellular pathogen have been identified in host tissues. Our findings imply a role for O. viverrini EVs in pathogenesis and highlight an approach to vaccine development for this infectious cancer. PMID:25985904

  18. Characterisation of two calmodulin-like proteins from the liver fluke, Fasciola hepatica.

    PubMed

    Russell, Sean L; McFerran, Neil V; Hoey, Elizabeth M; Trudgett, Alan; Timson, David J

    2007-06-01

    Calmodulin is a calcium ion-sensing signalling protein found in eukaryotics. Two calmodulin-like gene sequences were identified in an EST library from adult liver flukes. One codes for a protein (FhCaM1) homologous to mammalian calmodulins (98% identity), whereas the other protein (FhCaM2) has only 41% identity. These genes were cloned into expression vectors and the recombinant proteins were expressed in Escherichia coli. Gel shift assays showed that both proteins bind to calcium, magnesium and zinc ions. Homology models have been built for both proteins. As expected, FhCaM1 has a highly similar structure to other calmodulins. Although FhCaM2 has a similar fold, its surface charge is higher than FhCaM1. One of the potential metal ion-binding sites has lower metal-ion co-ordination capability, while another has an adjacent lysine residue, both of which may decrease the metal-binding affinity. These differences may reflect a specialised role for FhCaM2 in the liver fluke.

  19. Molecular expression and enzymatic characterization of thioredoxin from the carcinogenic human liver fluke Opisthorchis viverrini.

    PubMed

    Suttiprapa, Sutas; Matchimakul, Pitchaya; Loukas, Alex; Laha, Thewarach; Wongkham, Sopit; Kaewkes, Sasithorn; Brindley, Paul J; Sripa, Banchob

    2012-03-01

    The human liver fluke, Opisthorchis viverrini, induces inflammation of the hepatobiliary system. Despite being constantly exposed to inimical oxygen radicals released from inflammatory cells, the parasite survives for years. Defense against oxidative damage can be mediated through glutathione and/or thioredoxin utilizing systems. Here, we report the molecular expression and biochemical characterization of a thioredoxin (Trx) from O. viverrini. O. viverrini Trx cDNA encoded a polypeptide of 105 amino acid residues, of molecular mass 11.63 kDa. The predicted protein has similarity to previously characterized thioredoxins with 26-51% identity. Recombinant O. viverrini Trx (Ov-Trx-1) was expressed as soluble protein in E. coli. The recombinant protein showed insulin reduction activity and supported the enzymatic function of O. viverrini thioredoxin peroxidase. Expression of Ov-Trx-1 at mRNA and protein levels was observed in all obtainable developmental stages of the liver fluke. Ov-Trx-1 was also detected in excretory-secretory products released by adult O. viverrini. Immunohistochemistry, Ov-Trx-1 was expressed in nearly all parasite tissue excepted ovary and mature sperms. Interestingly, Ov-Trx-1 was observed in the infected biliary epithelium but not in normal bile ducts. These results suggest that Ov-Trx-1 is essential for the parasite throughout the life cycle. In the host-parasite interaction aspect, Ov-Trx-1 may support thioredoxin peroxidase in protecting the parasite against damage induced by reactive oxygen species from inflammation.

  20. In vitro screening of Cymbopogon jwarancusa and Conyza canadensis against liver flukes.

    PubMed

    Shafiq, Andeela; Kanwal, Rabia; Ullah Qureshi, Rahamat; Riaz Chaudhry, Farhana

    2015-09-01

    Aim of present study was to screen medicinal plants for flukicidal activity in vitro to develop alternative sources of treatment for trematodes infection. For this purpose, crude methanolic extracts (CME) of Cymbopogn jwarancusa and Conyza canadensis were prepared and live adult flukes viz; Fasciola gigantica, and Paramphistomum cervi isolated from liver and bile ducts of slaughtered buffalo were subjected to different drug concentrations as well as positive and negative control. Motility inhibition and paralysis leading to the death of parasites was considered as flukicidal activity of plants extracts. The results revealed that CME of C. jwarancusa and C. canadensis showed significant (P<0.05) flukicidal activity compared to positive control. Also there was a significant effect of different concentrations (P<0.05) and exposure of time on the flukes (P<0.05). Furthermore, ED50 for C. jwarancusa and C. canadensis against F. gigantica were 13.1 and 41.4 mg/ml, respectively. In the case of P. cervi, it was 10.8 and 29.0 mg/ml. It can be concluded that both tested plants showed greater flukicidal activity as compared to positive control with Albendazole till the 8(th) hr. These potent plants needs further studies invivo to elucidate their mode of action.

  1. Metabolism of drugs and other xenobiotics in giant liver fluke (Fascioloides magna).

    PubMed

    Prchal, Lukáš; Vokřál, Ivan; Kašný, Martin; Rejšková, Lenka; Zajíčková, Markéta; Lamka, Jiří; Skálová, Lenka; Lecová, Lenka; Szotáková, Barbora

    2016-01-01

    1. Giant liver fluke Fascioloides magna is a dangerous parasite, which infects herbivores. It was imported to Europe from North America and started to spread. Benzimidazoles like albendazole, mebendazole, triclabendazole and salicylanilides closantel and rafoxanide are the most used anthelmintics to control fascioloidosis. However their effect might be altered via drug-metabolizing enzymes of this parasite. 2. The aim of our study was to determine the activities of drug-metabolizing enzymes in F. magna and the metabolism of above mentioned anthelmintics. 3. Activities of several oxidative, reductive and conjugative enzymes towards various model xenobiotic substrates were found in F. magna subcellular fractions. 4. Subcellular fractions from F. magna oxidized albendazole to its sulphoxide metabolite and reduced mebendazole to hydroxyl-mebendazole. Under ex vivo conditions, only very-low concentrations of these compounds were detected using high-performance liquid chromatography/mass spectrometry. 5. The results indicate that the giant liver fluke possesses the active xenobiotic-metabolizing system. The overexpression of this system may play an important role in parasite resistance against these anthelmintics.

  2. Fasciola hepatica: Histology of the Reproductive Organs and Differential Effects of Triclabendazole on Drug-Sensitive and Drug-Resistant Fluke Isolates and on Flukes from Selected Field Cases

    PubMed Central

    Hanna, Robert

    2015-01-01

    This review summarises the findings of a series of studies in which the histological changes, induced in the reproductive system of Fasciola hepatica following treatment of the ovine host with the anthelmintic triclabendazole (TCBZ), were examined. A detailed description of the normal macroscopic arrangement and histological features of the testes, ovary, vitelline tissue, Mehlis’ gland and uterus is provided to aid recognition of the drug-induced lesions, and to provide a basic model to inform similar toxicological studies on F. hepatica in the future. The production of spermatozoa and egg components represents the main energy consuming activity of the adult fluke. Thus the reproductive organs, with their high turnover of cells and secretory products, are uniquely sensitive to metabolic inhibition and sub-cellular disorganisation induced by extraneous toxic compounds. The flukes chosen for study were derived from TCBZ-sensitive (TCBZ-S) and TCBZ-resistant (TCBZ-R) isolates, the status of which had previously been proven in controlled clinical trials. For comparison, flukes collected from flocks where TCBZ resistance had been diagnosed by coprological methods, and from a dairy farm with no history of TCBZ use, were also examined. The macroscopic arrangement of the reproductive system in flukes was studied using catechol/carmine stained whole mounts, and the histology of the main organs was examined using conventional haematoxylin-eosin stained sections. Validation of apoptosis in the fluke sections was carried out using an in situ hybridisation method designed to label endonuclease-induced DNA strand breaks. In TCBZ-S flukes exposed to TCBZ metabolites for 24–96 h in vivo, but not in TCBZ-R flukes, those tissues where active meiosis and/or mitosis occurred (testis, ovary, and vitelline follicles), were found to display progressive loss of cell content. This was due to apparent failure of cell division to keep pace with expulsion of the mature or effete products

  3. Fasciola hepatica: Histology of the Reproductive Organs and Differential Effects of Triclabendazole on Drug-Sensitive and Drug-Resistant Fluke Isolates and on Flukes from Selected Field Cases.

    PubMed

    Hanna, Robert

    2015-06-26

    This review summarises the findings of a series of studies in which the histological changes, induced in the reproductive system of Fasciola hepatica following treatment of the ovine host with the anthelmintic triclabendazole (TCBZ), were examined. A detailed description of the normal macroscopic arrangement and histological features of the testes, ovary, vitelline tissue, Mehlis' gland and uterus is provided to aid recognition of the drug-induced lesions, and to provide a basic model to inform similar toxicological studies on F. hepatica in the future. The production of spermatozoa and egg components represents the main energy consuming activity of the adult fluke. Thus the reproductive organs, with their high turnover of cells and secretory products, are uniquely sensitive to metabolic inhibition and sub-cellular disorganisation induced by extraneous toxic compounds. The flukes chosen for study were derived from TCBZ-sensitive (TCBZ-S) and TCBZ-resistant (TCBZ-R) isolates, the status of which had previously been proven in controlled clinical trials. For comparison, flukes collected from flocks where TCBZ resistance had been diagnosed by coprological methods, and from a dairy farm with no history of TCBZ use, were also examined. The macroscopic arrangement of the reproductive system in flukes was studied using catechol/carmine stained whole mounts, and the histology of the main organs was examined using conventional haematoxylin-eosin stained sections. Validation of apoptosis in the fluke sections was carried out using an in situ hybridisation method designed to label endonuclease-induced DNA strand breaks. In TCBZ-S flukes exposed to TCBZ metabolites for 24-96 h in vivo, but not in TCBZ-R flukes, those tissues where active meiosis and/or mitosis occurred (testis, ovary, and vitelline follicles), were found to display progressive loss of cell content. This was due to apparent failure of cell division to keep pace with expulsion of the mature or effete products

  4. Multiple liver abscesses in a dog secondary to the liver fluke Metorchis conjunctus treated by percutaneous transhepatic drainage and alcoholization.

    PubMed

    Lemetayer, Julie D; Snead, Elizabeth C; Starrak, Greg S; Wagner, Brent A

    2016-06-01

    A 1-year-old German shepherd × husky cross dog was diagnosed with multiple liver abscesses and severe cholangitis secondary to the liver fluke Metorchis conjunctus. The dog was successfully treated with 2 percutaneous transhepatic drainage and alcoholization procedures, and a prolonged course of antibiotics and praziquantel.

  5. [The polymorphism and structural peculiarities of two noncoding regions of liver fluke Fasciola hepatica (Plathelminthes: Trematoda) mitochondrial genome].

    PubMed

    Korchagina, E V; Vasil'ev, V A; Korchagin, V I; Movsesian, S O; Semenova, S K

    2009-01-01

    Structural characteristics and polymorphism of long (LNR) and short (SNR) mitochondrial non-coding regions of the liver fluke Fasciola hepatica were studied. The flukes were obtained from several populations of Russia and Belarus. The amplification of LNR yielded a set of 10 fragments with the length of neighbouring ones differing in one tandem repeat (85 bp; published earlier for Australian fluke). LNR amplification fragments of different length were cloned and sequenced. Comparison of the LNR sequences of Australian and Belarussian flukes revealed 3 nucleotide substitutions and one point heteroplasmy of the first nucleotides in the imperfect repeat and four adjacent perfect repeats. Positions of the three mutations coincide in perfect and imperfect repeats and the frequency of mutations is 4-4.7% while the frequency of heteroplasmic sites varies from 0.1 to 1.2%. It was shown that the presence of mutations and the heteroplasmy of one site can change the structure and stability of the putative secondary structures of the perfect and imperfect re- peats. The amplification of SNR of F. hepatica from several populations yielded fragments which differed from the published SNR sequence of Australian F. hepatica in the single transversion. Both non-coding regions have several conservative and potentially regulatory sequences. Probable cause of heteroplasmy and concerted origin of substitutions in different repeats are discussed.

  6. Multiple liver abscesses in a dog secondary to the liver fluke Metorchis conjunctus treated by percutaneous transhepatic drainage and alcoholization

    PubMed Central

    Lemetayer, Julie D.; Snead, Elizabeth C.; Starrak, Greg S.; Wagner, Brent A.

    2016-01-01

    A 1-year-old German shepherd × husky cross dog was diagnosed with multiple liver abscesses and severe cholangitis secondary to the liver fluke Metorchis conjunctus. The dog was successfully treated with 2 percutaneous transhepatic drainage and alcoholization procedures, and a prolonged course of antibiotics and praziquantel. PMID:27247459

  7. Detection of major climatic and environmental predictors of liver fluke exposure risk in Ireland using spatial cluster analysis.

    PubMed

    Selemetas, Nikolaos; de Waal, Theo

    2015-04-30

    Fasciolosis caused by Fasciola hepatica (liver fluke) can cause significant economic and production losses in dairy cow farms. The aim of the current study was to identify important weather and environmental predictors of the exposure risk to liver fluke by detecting clusters of fasciolosis in Ireland. During autumn 2012, bulk-tank milk samples from 4365 dairy farms were collected throughout Ireland. Using an in-house antibody-detection ELISA, the analysis of BTM samples showed that 83% (n=3602) of dairy farms had been exposed to liver fluke. The Getis-Ord Gi* statistic identified 74 high-risk and 130 low-risk significant (P<0.01) clusters of fasciolosis. The low-risk clusters were mostly located in the southern regions of Ireland, whereas the high-risk clusters were mainly situated in the western part. Several climatic variables (monthly and seasonal mean rainfall and temperatures, total wet days and rain days) and environmental datasets (soil types, enhanced vegetation index and normalised difference vegetation index) were used to investigate dissimilarities in the exposure to liver fluke between clusters. Rainfall, total wet days and rain days, and soil type were the significant classes of climatic and environmental variables explaining the differences between significant clusters. A discriminant function analysis was used to predict the exposure risk to liver fluke using 80% of data for modelling and the remaining subset of 20% for post hoc model validation. The most significant predictors of the model risk function were total rainfall in August and September and total wet days. The risk model presented 100% sensitivity and 91% specificity and an accuracy of 95% correctly classified cases. A risk map of exposure to liver fluke was constructed with higher probability of exposure in western and north-western regions. The results of this study identified differences between clusters of fasciolosis in Ireland regarding climatic and environmental variables and

  8. Effect of gastrointestinal nematode and liver fluke infections on weight gain and reproductive performance of beef heifers.

    PubMed

    Loyacano, A F; Williams, J C; Gurie, J; DeRosa, A A

    2002-08-02

    Spring born, crossbred beef heifers (n=372) were utilized over four years to measure reductions in body weights, reproductive performance and calf weights caused by gastrointestinal nematodes (primarily Ostertagia ostertagi) and the bovine liver fluke (Fasciola hepatica) and to differentiate losses attributable to each type of parasitism. Each year, weaned heifers were allotted to one of the four treatment regimens: Group 1, untreated controls; Group 2, treated for nematodes; Group 3, treated for liver fluke; and Group 4, treated for both nematodes and liver fluke. Nematodes were controlled with subcutaneous injections of either ivermectin (Ivomec, Merial) or doramectin (Dectomax, Pfizer), both at the recommended dose of 200 ug/kg bodyweight. Clorsulon (Curatrem, Merial) drench was given at the recommended rate of 7 mg/kg bodyweight to control flukes. Treatments and fecal collections were initiated at allotment each year and were repeated at 28-84-day intervals until palpation for pregnancy diagnosis. Open heifers were removed from the study at this time. Treatment dates were based on expected length of treatment efficacy, the stage of growth of the heifers and the seasonal risk of infection by the parasites. Pregnant females were pooled and received their assigned treatments prior to their calving and breeding seasons and remained together until their calves were weaned. Heifers treated for nematode infections were heavier and had higher condition scores (P<0.01) than untreated control heifers at initiation of breeding, and maintained that difference through pregnancy diagnosis. Liver fluke infection did not affect heifer gains or condition scores prior to palpation (P<0.01). At palpation, heifers treated for both forms of parasitism had the highest condition scores and weight gains (P<0.01), and also higher pregnancy rates than control heifers and heifers treated for nematodes only (P<0.01). Pregnancy rates for heifers treated for flukes only were not

  9. AMU NEXRAD Exploitation Task

    NASA Technical Reports Server (NTRS)

    Lambert, Winifred C.; Wheeler, Mark M.

    1997-01-01

    This report documents the results of the Applied Meteorology Unit's NEXRAD Exploitation Task. The objectives of this task are to determine what radar signatures are present prior to and at the time of convection initiation, and to determine radar signatures which will help distinguish whether the ensuing convection will become severe. Radar data from the WSR-88D radar located at NWS Melbourne (WSR-88D/KMLB) were collected between June and September 1995, and 16 convective case studies were analyzed for which the radar was operating during the entire period of interest. All WSR-88D/KMLB products were scrutinized for their utility in detecting convection initiation and severe storm signatures. Through process of elimination, it was found that the 0.5 deg reflectivity product with the lowest reflectivity values displayed is the best product to monitor for convection initiation signatures. Seven meteorological features associated with the initiation of deep convection were identified: the Merritt Island and Indian River convergence zones, interlake convergence, horizontal convective rolls, the sea breeze, storm outflow boundaries, and fires. Their reflectivity values ranged from -5 to 20 dBZ. Of the three severe weather phenomena (winds greater than or equal to 50 kts, tornado, 3/4 inch hail), high wind events due to microbursts were most common in the data set. It was found that the values and trends of composite reflectivity, vertically integrated liquid, and core aspect ratio were key indicators of the potential of a cell to produce a microburst. The data were not analyzed for the other two severe weather phenomena because they rarely occurred during the data collection period. This report also includes suggestions for new WSR-88D products, summaries of ongoing research aimed at creating new products, and explicit recommended procedures for detecting convection initiation and severe storm signatures in the radar data using the currently available technology.

  10. Efficacy of treatment of cattle for liver fluke at housing: influence of differences in flukicidal activity against juvenile Fasciola hepatica.

    PubMed

    Forbes, A B; Reddick, D; Stear, M J

    2015-03-28

    Flukicides are commonly administered at housing to cattle that have grazed fluke-infected pastures or that have been purchased from endemic areas. The choice of product is determined by numerous factors, one of which is the stages of Fasciola hepatica that are killed. Flukicides can be categorised into three main groups: (A) those that kill all juvenile stages and adults; (B) those that kill juveniles from six to eight weeks of age and adults and (C) those that kill adults only. This study was conducted on a commercial beef farm in Scotland and was designed to compare the efficacy of flukicides from each of these three classes in terms of their effects on faecal egg output, coproantigen and liveweight gain. The majority of animals in the untreated control group were positive for coproantigen, fluke eggs or both throughout the study duration of 16 weeks. Egg reappearance interval following housing treatment was eight weeks for clorsulon and 13 weeks for nitroxynil, though patent infections in both groups developed in only a small minority of animals; no fluke eggs were recovered from cattle treated with triclabendazole. Coproantigen was detected four weeks before the reappearance of fluke eggs in the dung. Animals treated with flukicides had significantly fewer faecal samples positive for eggs (P<0.006) and coproantigen (P<0.05) following treatment compared with the controls. Despite differences in the efficacy profiles among the flukicide-treated groups, there were no significant differences (P>0.05) in growth rates among any of the four treatment groups. There was, however, a significant negative association (P<0.001) between fluke positivity at housing and subsequent growth performance, irrespective of treatment group. British Veterinary Association.

  11. The secreted and surface proteomes of the adult stage of the carcinogenic human liver fluke Opisthorchis viverrini

    PubMed Central

    Mulvenna, Jason; Sripa, Banchob; Brindley, Paul J.; Gorman, Jeffrey; Jones, Malcolm K.; Colgrave, Michelle L.; Jones, Alun; Nawaratna, Sujeevi; Laha, Thewarach; Suttiprapa, Sutas; Smout, Michael J.; Loukas, Alex

    2011-01-01

    Infection with the human liver fluke, Opisthorchis viverrini, is a serious public health problem in Thailand, Laos and nearby locations in Southeast Asia. Both experimental and epidemiological evidence strongly implicate liver fluke infection in the etiology of one of the liver cancer subtypes, cholangiocarcinoma (CCA). To identify parasite proteins critical for liver fluke survival and the etiology of CCA, OFFGEL electrophoresis and Multiple reaction monitoring were employed to characterize 300 parasite proteins from the O. viverrini excretory/secretory products (ES) and, utilizing selective labeling and sequential solubilization, from the host-exposed tegument. The ES included a complex mixture of proteins that have been associated with cancers, including proteases of different mechanistic classes and orthologues of mammalian growth factors and anti-apoptotic proteins. Also identified was a cysteine protease inhibitor which, in other helminth pathogens, induces nitric oxide production by macrophages, and, hence may contribute to malignant transformation of inflamed cells. Proteases in ES included cathepsins, calpain and a protein with homology to autoimmune prostatitis antigen 2. More than 160 tegumental proteins were identified using sequential solubilization of isolated teguments, and a subset of these was localized to the surface membrane of the tegument by labeling living flukes with biotin and confirming surface localization with fluorescence microscopy. These included annexins, which are potential immuno-modulators, and orthologues of the schistosomiasis vaccine antigens Sm29 and tetraspanin-2. Novel roles in pathogenesis were suggested for the tegument-host interface since more than ten biotinylated surface proteins had no homologues in the public databases. The O. viverrini proteins identified here provide an extensive catalogue of novel leads for research on the pathogenesis of opisthorchiasis and the development of novel interventions for this disease

  12. Asparaginyl endopeptidase from the carcinogenic liver fluke, Opisthorchis viverrini, and its potential for serodiagnosis

    PubMed Central

    Laha, Thewarach; Sripa, Jittiyawadee; Sripa, Banchob; Pearson, Mark; Tribolet, Leon; Kaewkes, Sasithorn; Sithithaworn, Paiboon; Brindley, Paul J.; Loukas, Alex

    2008-01-01

    Summary Objectives To isolate and characterize an asparaginyl endopeptidase from the carcinogenic liver fluke, Opisthorchis viverrini, and evaluate its expression profile, biochemical activity, and potential as an immunodiagnostic antigen. Methods The full length mRNA encoding an asparaginyl endopeptidase (family C13), Ov-aep-1, was isolated by immunoscreening of a cDNA bacteriophage library of adult O. viverrini using sera from patients infected with O. viverrini. Investigation of Ov-aep-1 transcripts in developmental stages of the parasite, and phylogenetic analysis, immunohistochemical localization, and recombinant protein expression and enzymology were employed to characterize the Ov-AEP-1 protein. Immunoblotting was used to assess the potential of this enzyme for immunodiagnosis of human opisthorchiasis. Results Ov-AEP-1 is characteristic of the C13 cysteine protease family. Ov-aep-1 transcripts were detected in adult and juvenile worms, eggs, and metacercariae. Phylogenetic analysis indicated that Ov-AEP-1 is closely related to homologous proteins in other trematodes. Recombinant Ov-AEP-1 was expressed in bacteria in inclusion bodies and refolded to a soluble form. Excretory–secretory (ES) products derived from adult O. viverrini and refolded recombinant Ov-AEP-1 both displayed catalytic activity against the diagnostic tripeptide substrate, Ala–Ala–Asn-aminomethylcoumarin. Rabbit antiserum raised to recombinant Ov-AEP-1 identified the native AEP-1 protease in both somatic extract and ES products of adult worms. Anti-Ov-AEP-1 IgG immunolocalized the anatomical site of expression to the gut of the fluke, implying a physiological role in digestion of food or activation of other digestive enzymes. Recombinant Ov-AEP-1 was recognized by serum antibodies from patients with opisthorchiasis but not other helminth infections, with a sensitivity and specificity of 85% and 100%, respectively. The positive and negative predictive values are 100% and 67

  13. Helminths and helminthoses in Central Europe: general overview and diseases caused by trematodes (flukes).

    PubMed

    Auer, Herbert; Aspöck, Horst

    2014-10-01

    Parasitic helminths and helminthoses do not only occur in the tropics and subtropics but are also prevalent in Austria and other Central European countries. Their prevalence is, however, more or less rather low. In total, we know more than 20 helminth species, which are diagnosed regularly in Austria; some of them occur in Austria autochthonously, some others are acquired abroad and are transferred as souvenirs to Central Europe. The spectrum of helminths described in this overview comprises species of the trematodes (flukes), cestodes (tapeworms), and nematodes (roundworms).The topic "Helminths and helminthoses in Central Europe" is divided into three parts: The first part comprises a short introduction into the field of medical helminthology and is primarily dedicated to the description of trematodes and trematode-caused diseases.

  14. Risk Factors for Opisthorchis viverrini and Minute Intestinal Fluke Infections in Lao PDR, 2009–2011

    PubMed Central

    Yoon, Hee Jung; Ki, Moran; Eom, Keeseon; Yong, Tai-Soon; Chai, Jong-Yil; Min, Duk-Young; Rim, Han-Jong; Sohn, Woon-Mok; Insisiengmay, Bounnaloth; Phommasack, Bounlay

    2014-01-01

    The purpose of this report is to compare the prevalence of Opisthorchis viverrini/minute intestinal fluke (Ov/MIF) in Lao People's Democratic Republic according to different regions and evaluate the effect of ingestion of raw freshwater fish on the infection. Demographic data, behavioral data, and symptoms were obtained, and the Kato–Katz method was used for the diagnosis of Ov/MIF. In total, 3,046 individuals were enrolled. The risk factors associated with acquisition of Ov/MIF were raw fish consumption and province. Khong Island showed the highest prevalence (odds ratio = 80.1, 95% confidence interval = 47.9–133.9, P < 0.001) compared with other districts, and raw fish consumption was related to Ov/MIF infection. Administration of praziquantel to entire populations, education (avoiding consumption of raw food dishes and improved hygiene), and access to clean water and sanitation should be considered. PMID:24980495

  15. Liver fluke disease (fascioliasis): epidemiology, economic impact and public health significance.

    PubMed

    Saleha, A A

    1991-12-01

    Liver fluke disease (fascioliasis) is an important parasitic disease found worldwide affecting sheep, goats, cattle and buffalo, as well as other domestic ruminants. The common causative agents are Fasciola hepatica and F. gigantica which require various species of Lymnaea, fresh water snails, as their intermediate hosts. The epidemiology of the disease and its prevalence in Malaysia is mentioned briefly. The disease causes considerable impact on the economy of the livestock industry. The economic losses consist of costs of anthelmintics, drenches, labor, liver condemnation at meat inspection; and losses in production due to mortality, reduction in meat, milk and wool production; and reduction in growth rate, fertility and draught power. The disease also has public health significance, causing human fascioliasis and "halzoun".

  16. Prevalence of Opisthorchis viverrini-Like Fluke Infection in Ducks in Binh Dinh Province, Central Vietnam.

    PubMed

    Dao, Thanh Thi Ha; Abatih, Emmanuel Nji; Nguyen, Thanh Thi Giang; Tran, Ha Thi Lam; Gabriël, Sarah; Smit, Suzanne; Le, Phap Ngoc; Dorny, Pierre

    2016-06-01

    Following the first report of Opisthorchis viverrini infection in a domestic duck in Phu My District of Binh Dinh Province, Central Vietnam, many other cases were observed in the province. We determined the infection rate and intensity of O. viverrini infection in ducks in 4 districts of the province. A total of 178 ducks were randomly selected from 34 farms for examination of flukes in the liver and gall bladder. An infection rate of 34.3% (range 20.7-40.4% among districts) was found; the intensity of infection was 13.8 worms per infected duck (range 1-100). These findings show the role of ducks as a host for O. viverrini, duck genotype, which is sympatric with the human O. viverrini genotype in this province. It also stresses the need for investigations on the zoonotic potential and the life cycle of this parasite.

  17. Prevalence of Opisthorchis viverrini-Like Fluke Infection in Ducks in Binh Dinh Province, Central Vietnam

    PubMed Central

    Dao, Thanh Thi Ha; Abatih, Emmanuel Nji; Nguyen, Thanh Thi Giang; Tran, Ha Thi Lam; Gabriël, Sarah; Smit, Suzanne; Le, Phap Ngoc; Dorny, Pierre

    2016-01-01

    Following the first report of Opisthorchis viverrini infection in a domestic duck in Phu My District of Binh Dinh Province, Central Vietnam, many other cases were observed in the province. We determined the infection rate and intensity of O. viverrini infection in ducks in 4 districts of the province. A total of 178 ducks were randomly selected from 34 farms for examination of flukes in the liver and gall bladder. An infection rate of 34.3% (range 20.7-40.4% among districts) was found; the intensity of infection was 13.8 worms per infected duck (range 1-100). These findings show the role of ducks as a host for O. viverrini, duck genotype, which is sympatric with the human O. viverrini genotype in this province. It also stresses the need for investigations on the zoonotic potential and the life cycle of this parasite. PMID:27417094

  18. The zoonotic, fish-borne liver flukes Clonorchis sinensis, Opisthorchis felineus and Opisthorchis viverrini.

    PubMed

    Petney, Trevor N; Andrews, Ross H; Saijuntha, Weerachai; Wenz-Mücke, Alexandra; Sithithaworn, Paiboon

    2013-11-01

    Clonorchis sinensis, Opisthorchis felineus and Opisthorchis viverrini are the three most important liver flukes involved in human health, infecting more than 45 million people worldwide. Both C. sinensis and O. viverrini, and possibly O. felineus, can induce human cholangiocarcinoma as well as inducing other hepatobiliary pathology. Although the life cycles of all three species are similar, only that of O. felineus in Europe remains predominantly zoonotic, while O. felineus in Asia and C. sinensis have a stronger mixture of zoonotic and anthroponotic components in their life cycles. Opisthorchis viverrini from the Mekong area of southeastern Asia is predominantly anthroponotic. Here we discuss the comparative epidemiology of these three taxa comparing in detail the use of first, second and final animal hosts, and consider the potential role of humans in spreading these pathogens. In addition we discuss the genetic structure of all three species in relation to potentially cryptic species complexes.

  19. Pathological changes in cattle naturally infected by Calicophoron daubneyi adult flukes.

    PubMed

    Fuertes, Miguel; Pérez, Valentín; Benavides, Julio; González-Lanza, M Camino; Mezo, Mercedes; González-Warleta, Marta; Giráldez, Francisco Javier; Fernández, Miguel; Manga-González, M Yolanda; Ferreras, M Carmen

    2015-04-30

    Local host response and parasite distribution were studied in the forestomachs, abomasum, duodenum and regional lymph nodes of cattle suffering from bovine paramphistomosis. The parasites were found attached, by its ventral sucker, to small conical papillae of the rumen and reticulum. Affected papillae, showed morphological changes denoted by very narrow stalks and expanded heads. Histologically, these changes were characterized by epithelial acanthosis-hyperkeratosis of the epithelium. Infiltration of inflammatory cells was often related with the epithelial changes, although it was also found in the duodenal mucosa and submucosa. These cells were arranged as aggregates or follicles but sparse infiltration of eosinophils, globule leukocytes, mast cells or macrophages was also observed in the lamina propria. Tissue damage and inflammatory reaction were more severe in the ruminal atrium, where the largest number of flukes and affected papillae were observed. In contrast, lesions in the ruminal dorsal sac were absent or mild. Statistical correlation between lesion severity and parasite burden was confirmed.

  20. Genome-wide characterization of microsatellites and marker development in the carcinogenic liver fluke Clonorchis sinensis.

    PubMed

    Nguyen, Thao T B; Arimatsu, Yuji; Hong, Sung-Jong; Brindley, Paul J; Blair, David; Laha, Thewarach; Sripa, Banchob

    2015-06-01

    Clonorchis sinensis is an important carcinogenic human liver fluke endemic in East and Southeast Asia. There are several conventional molecular markers that have been used for identification and genetic diversity; however, no information about microsatellites of this liver fluke is published so far. We here report microsatellite characterization and marker development for a genetic diversity study in C. sinensis, using a genome-wide bioinformatics approach. Based on our search criteria, a total of 256,990 microsatellites (≥12 base pairs) were identified from a genome database of C. sinensis, with hexanucleotide motif being the most abundant (51%) followed by pentanucleotide (18.3%) and trinucleotide (12.7%). The tetranucleotide, dinucleotide, and mononucleotide motifs accounted for 9.75, 7.63, and 0.14%, respectively. The total length of all microsatellites accounts for 0. 72% of 547 Mb of the whole genome size, and the frequency of microsatellites was found to be one microsatellite in every 2.13 kb of DNA. For the di-, tri-, and tetranucleotide, the repeat numbers redundant are six (28%), four (45%), and three (76%), respectively. The ATC repeat is the most abundant microsatellites followed by AT, AAT, and AC, respectively. Within 40 microsatellite loci developed, 24 microsatellite markers showed potential to differentiate between C. sinensis and Opisthorchis viverrini. Seven out of 24 loci showed to be heterozygous with observed heterozygosity that ranged from 0.467 to 1. Four primer sets could amplify both C. sinensis and O. viverrini DNA with different sizes. This study provides basic information of C. sinensis microsatellites, and the genome-wide markers developed may be a useful tool for the genetic study of C. sinensis.

  1. Prevalence of gastrointestinal helminths, lungworms and liver fluke in sheep and goats in Norway.

    PubMed

    Domke, Atle V Meling; Chartier, Christophe; Gjerde, Bjørn; Leine, Nils; Vatn, Synnøve; Stuen, Snorre

    2013-05-01

    The present study describes the occurrence of various gastrointestinal helminths, lungworms and liver flukes in Norwegian sheep and goats as assessed from faecal samples and post mortem examinations performed between 2007 and 2010. Faecal samples for gastrointestinal nematode egg counts were collected from 77 sheep flocks and 30 dairy goat flocks from three geographical regions in Norway. Additionally, thirty-two lambs and 16 adult goats were euthanized for necropsy examination and for identification of adult gastrointestinal nematodes and tapeworms, lungworms and liver flukes. The survey showed that there was a higher mean excretion of trichostrongyle eggs in sheep than in goats at the individual level (392 EPG vs. 154 EPG, p<0.001). For both host species, the mean prevalence and intensity of excreted trichostrongyle eggs were significantly higher in the southern coastal region compared with the inland and northern regions (p<0.001). Third stage larvae of Trichostrongylus/Teladorsagia, Haemonchus and Nematodirus type were the most prevalent ones in the coprocultures from sheep, whereas larvae of Trichostrongylus/Teladorsagia and Nematodirus type dominated in goats. The most prevalent gastrointestinal nematode species found at necropsy was Teladorsagia circumcincta (75.0 and 81.2% respectively in sheep and goats), while the largest mean worm burdens were recorded for Haemonchus contortus in sheep (724±623) and T. circumcincta in goats (377±529). Other gastrointestinal nematode species were present at low prevalence or in low numbers. Fasciola hepatica was only found in necropsied sheep from the coastal region with a prevalence of 18.8%. The lungworm Mullerius capillaris was found from all regions in necropsied goats (31.2%) and from coastal area in sheep (3.1%). The present study indicates that H. contortus and Nematodirus battus have a wider geographical distribution to the north than expected, and describes to our knowledge the northernmost occurrence of H

  2. Genetic diversity of the Chinese liver fluke Clonorchis sinensis from Russia and Vietnam.

    PubMed

    Chelomina, Galina N; Tatonova, Yulia V; Hung, Nguyen Manh; Ngo, Ha Duy

    2014-10-01

    Clonorchiasis is a parasitic disease of high public health importance in many countries in southeastern Asia and is caused by the Chinese liver fluke Clonorchis sinensis. However, the genetic structure and demographic history of its populations has not been sufficiently studied throughout the geographic range of the species and available data are based mainly on partial gene sequencing. In this study, we explored the genetic diversity of the complete 1560 bp cytochrome c oxidase subunit 1 (cox1) gene sequence for geographically isolated C. sinensis populations in Russia and Vietnam, to our knowledge for the first time. The results demonstrated low nucleotide and high haplotype differentiation within and between the two compared regions and a clear geographical vector for the distribution of genetic diversity patterns among the studied populations. These results suggest a deep local adaptation of the parasite to its environment including intermediate hosts and the existence of gene flow across the species' range. Additionally, we have predicted an amino acid substitution in the functional site of the COX1 protein among the Vietnamese populations, which were reported to be difficult to treat with praziquantel. The haplotype networks consisted of several region-specific phylogenetic lineages, the formation of which could have occurred during the most extensive penultimate glaciations in the Pleistocene Epoch. The patterns of genetic diversity and demographics are consistent with population growth of the liver fluke in the late Pleistocene following the Last Glacial Maximum, indicating the lack of a population bottleneck during the recent past in the species' history. The data obtained have important implications for understanding the phylogeography of C. sinensis, its host-parasite interactions, the ability of this parasite to evolve drug resistance, and the epidemiology of clonorchiasis under global climate change. Copyright © 2014 Australian Society for

  3. Fasciola hepatica - monitoring the milky way? The use of tank milk for liver fluke monitoring in dairy herds as base for treatment strategies.

    PubMed

    Duscher, Ruth; Duscher, Georg; Hofer, Johannes; Tichy, Alexander; Prosl, Heinrich; Joachim, Anja

    2011-06-10

    In this study 595 lactating cows originating from 31 carinthian farms were investigated in accordance of liver fluke infection using individual and tank milk as well as individual blood and faecal samples. Two commercial ELISAs were used to test the milk and blood serum, and the results were compared with coproscopy and a commercial copro-antigen ELISA. Receiver operating characteristics (ROC) and two-graph operating characteristics (TG ROC) of tank milk results were conducted based on the individual milk to determine the minimum reliable in-herd antibody prevalence for the predominant condition in the investigation area. In 17.8% of the examined individuals located in 64.5% of the farms eggs were detected by coproscopy. The copro-antigen ELISA delivered 13.4% positive individuals from 54.8% of the farms. The milk ELISAs showed 42.7% (Euroclone) and 44.2% (Pourquier) positive cows on 90.3% of the farms. The blood samples were positive in 43% (Euroclone) and 45.2% (Pourquier) of the individuals from 90.3% to 96.8% of the herds, respectively. Based on the milk and the blood an average in-herd prevalence of 30-45% can be assumed. The serum and milk samples delivered correlating results with kappa values between 0.94 and 0.97, whereas the coproscopy and copro-antigen ELISA did not correlate well with the ELISA results. The two different ELISA tests highly correlated on individual and on herd level. Both showed a reliable minimum in-herd prevalence of ∼20%, meaning that one fifth of the individuals in a herd have to be positive to obtain a positive bulk tank milk result. In the investigated area a higher in-herd prevalence is expected, therefore the tank milk is useful as a monitoring tool and can be used as a basis for intervention strategies. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Fasciola hepatica: comparative effects of host resistance and parasite intra-specific interactions on size and reproductive histology in flukes from rats infected with isolates differing in triclabendazole sensitivity.

    PubMed

    Hanna, R E B; Gordon, A W; Moffett, D; Edgar, H W J; Oliver, L F; McConnell, S; Shaw, L; Brennan, G P; Fairweather, I

    2011-06-10

    The efficacies of putative fasciolicides and vaccines against Fasciola hepatica are frequently monitored in clinical and field trials by determination of fluke egg output in host faeces and by worm counts in the host liver at autopsy. Less often used are parameters based on fluke size and histology, yet these can provide important indications of specific effects on the development of particular germ-line or somatic tissues, especially in relation to the timing and profligacy of egg production. In this study, F. hepatica metacercariae of two distinct isolates, the triclabendazole (TCBZ)-sensitive Cullompton isolate and the TCBZ-resistant Oberon isolate, were administered to rats as single-isolate or mixed-isolate infections. At autopsy 16 weeks later individual adult flukes were counted, measured and the reproductive organs were examined histologically. The degree of development of the testis tubules in each fluke was represented by a numerical score, based on the proportion of the histological section profiles occupied by testis tissue. The level of anti-F. hepatica antibody in the serum of each rat was determined by ELISA. It was found that Cullompton flukes were significantly larger than Oberon flukes, and that significantly more Cullompton metacercariae developed to adults than Oberon metacercariae. The Cullompton flukes showed histological evidence of aspermy and spermatogenic arrest, which was reflected in quantitatively reduced testicular development, as compared with the Oberon isolate. In Cullompton flukes, parthenogenetic egg development is implied. The size of Cullompton and Oberon flukes was significantly related to the number of adult flukes recovered, to the number of metacercariae administered, and to the percentage success of infection. The testis development score in both isolates was significantly related to the number of adult flukes recovered but not to the number of metacercariae administered, or to the percentage success of infection. Fluke

  5. Guillain-Barré Syndrome in a Boy With Lung Fluke Infection: Case Report and Literature Review.

    PubMed

    Yang, Cui-Wei; Gao, Feng; Xia, Zhe-Zhi

    2015-08-01

    Guillain-Barré syndrome is the most common acute peripheral neuropathy in children in most countries. The cause and pathogenesis of the disease have yet to be clarified. There have been only a few reports of Guillain-Barré syndrome resulting from parasite infections worldwide, no cases of Guillain-Barré syndrome after lung fluke infection have been reported. We report a case of an 8-year-old male patient with Guillain-Barré syndrome after lung fluke infection. The child had a history of consumption of undercooked crabs. He was diagnosed with paragonimiasis. The patient experienced paralysis of and pain in the lower limbs about 3 weeks after symptom onset. Neurologic and electrophysiologic examination findings supported the diagnosis of Guillain-Barré syndrome. Parasitic infections should also be considered when determining which antecedent infection is associated with Guillain-Barré syndrome.

  6. [The influence of insulin on contamination of the common carp Cyprinus carpio by the monogenetic fluke Dactylogyrus vastator].

    PubMed

    Mikriakov, B P; Mikriakov, D B; Stepanova, M A

    2011-01-01

    The influence of insulin on the contamination of the carp Cyprinus carpio with the monogenetic fluke Dactylogyrus vastator is studied. Fishes reacted to the introduction of the hormon by the decrease in the degree of intensity of infection and by the increase in the number of lifeless parasites on gills, by contrast to control fishes and fishes processed with stress hormones (adrenaline and cortisol). We assume that the decrease in the abundance index in live monogenetic fluke and the increase in the number of lifeless oness is caused by the deficiency of nutrients accessible for the growth and development caused by activation of hormone-induced anabolic processes and stimulation of mechanisms of immune protection.

  7. Intervention to Improve the Quality of Life of a Bottlenose Dolphin That Developed Necrosis on the Tail Flukes

    PubMed Central

    Ueda, Keiichi; Murakami, Masahito; Kato, Junichi; Miyahara, Hirokazu; Izumisawa, Yasuharu

    2013-01-01

    [Purpose, Case, and Methods] A female bottlenose dolphin (Tursiops truncatus) in captivity developed necrosis of the tail flukes. Although the diseased site healed after surgical resection, the loss of approximately 75% of the tail greatly affected her swimming performance. To restore swimming ability, we developed artificial tail flukes as a prosthetic swimming aid and provided physical therapy that included swimming training from postoperative day 1 to day 1427. [Results] The prosthetic enabled the dolphin to recover swimming ability almost to the level prior to disease onset, but even acquire applied movement, and reestablish social relationships, thus greatly improving the animal's quality of life. [Conclusion] The results clearly demonstrate that, as in postoperative rehabilitation in humans, the use of prosthetic devices in physical therapy can be beneficial for marine animals such as dolphins. PMID:24259946

  8. Chinese liver flukes in latrine sediments from Wong Nim's property, San Bernardino, California: archaeoparasitology of the Caltrans District Headquarters.

    PubMed

    Reinhard, Karl J; Araújo, Adauto; Sianto, Luciana; Costello, Julia G; Swope, Karen

    2008-02-01

    Parasitological analysis of 5 sediment samples from San Bernardino, California latrine deposits spanning the time period from about 1880 to the 1930s are presented. Two sediment samples are from a latrine used by European-Americans. Three sediment samples are from latrines used by Chinese-Americans on the property of Wong Nim, an important member of the Chinese community. Two of the Chinese latrines were positive for human parasites. The human parasites encountered include the human whipworm (Trichuris trichiura), the giant intestinal roundworm (Ascaris lubricoides, c.f.), and the Chinese liver fluke (Clonorchis sinensis). Evidence of the liver fluke is especially important. This parasite cannot complete its life cycle outside of its endemic range in Asia because suitable intermediate hosts are not present in the American continents. Its presence signals that at least some of the Chinese-Americans who used the latrines were immigrants who were infected in Asia and then sustained infections while in the Americas.

  9. Stage-specific expression and antigenicity of glycoprotein glycans isolated from the human liver fluke, Opisthorchis viverrini.

    PubMed

    Talabnin, Krajang; Aoki, Kazuhiro; Saichua, Prasert; Wongkham, Sopit; Kaewkes, Sasithorn; Boons, Geert-Jan; Sripa, Banchob; Tiemeyer, Michael

    2013-01-01

    Infection by Opisthorchis viverrini (liver fluke) is a major public health problem in southeastern Asia, resulting in hepatobiliary disease and cholangiocarcinoma. Fluke surface glycoconjugates are prominently presented to the host, thereby constituting a crucial immunological interface that can determine the parasite's success in establishing infection. Therefore, N- and O-linked glycoprotein glycan profiles of the infective metacercarial stage and of the mature adult were investigated by nanospray ionisation-linear ion trap mass spectrometry (NSI-MS(n)). Glycan immunogenicity was investigated by immunoblotting with serum from infected humans. Metacercariae and adult parasites exhibit similar glycan diversity, although the prevalence of individual glycans and glycan classes varies by stage. The N-glycans of the metacercaria are mostly high mannose and monofucosylated, truncated-type oligosaccharides (62.7%), with the remainder processed to complex and hybrid type glycans (37.3%). The N-linked glycan profile of the adult is also dominated by high mannose and monofucosylated, truncated-type oligosaccharides (80.0%), with a smaller contribution from complex and hybrid type glycans (20.0%). At both stages, complex and hybrid type glycans are detected as mono-, bi-, tri-, or tetra-antennary structures. In metacercariae and adults, O-linked glycans are detected as mono- to pentasaccharides. The mucin type core 1 structure, Galβ1-3GalNAc, predominates in both stages but is less prevalent in the adult than in the metacercaria. Immunogenic recognition of liver fluke glycoproteins is reduced after deglycosylation but infected human serum was unable to recognise glycans released from peptides. Therefore, the most potent liver fluke antigenic epitopes are mixed determinants, comprised of glycan and polypeptide elements. Copyright © 2012 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

  10. Assessing the Role of Climate Variability on Liver Fluke Risk in the UK Through Mechanistic Hydro-Epidemiological Modelling

    NASA Astrophysics Data System (ADS)

    Beltrame, L.; Dunne, T.; Rose, H.; Walker, J.; Morgan, E.; Vickerman, P.; Wagener, T.

    2016-12-01

    Liver fluke is a flatworm parasite infecting grazing animals worldwide. In the UK, it causes considerable production losses to cattle and sheep industries and costs farmers millions of pounds each year due to reduced growth rates and lower milk yields. Large part of the parasite life-cycle takes place outside of the host, with its survival and development strongly controlled by climatic and hydrologic conditions. Evidence of climate-driven changes in the distribution and seasonality of fluke disease already exists, as the infection is increasingly expanding to new areas and becoming a year-round problem. Therefore, it is crucial to assess current and potential future impacts of climate variability on the disease to guide interventions at the farm scale and mitigate risk. Climate-based fluke risk models have been available since the 1950s, however, they are based on empirical relationships derived between historical climate and incidence data, and thus are unlikely to be robust for simulating risk under changing conditions. Moreover, they are not dynamic, but estimate risk over large regions in the UK based on monthly average climate conditions, so they do not allow investigating the effects of climate variability for supporting farmers' decisions. In this study, we introduce a mechanistic model for fluke, which represents habitat suitability for disease development at 25m resolution with a daily time step, explicitly linking the parasite life-cycle to key hydro-climate conditions. The model is used on a case study in the UK and sensitivity analysis is performed to better understand the role of climate variability on the space-time dynamics of the disease, while explicitly accounting for uncertainties. Comparisons are presented with experts' knowledge and a widely used empirical model.

  11. Fasciola hepatica: histological demonstration of apoptosis in the reproductive organs of flukes of triclabendazole-sensitive and triclabendazole-resistant isolates, and in field-derived flukes from triclabendazole-treated hosts, using in situ hybridisation to visualise endonuclease-generated DNA strand breaks.

    PubMed

    Hanna, R E B; Forster, F I; Brennan, G P; Fairweather, I

    2013-01-31

    Investigation of the triclabendazole (TCBZ) resistance status of populations of Fasciola hepatica in field cases of fasciolosis, where treatment failure has been reported, can be supported by histological examination of flukes collected from recently treated hosts. In TCBZ-sensitive flukes (TCBZ-S) exposed to TCBZ metabolites for 1-4days in vivo, but not in TCBZ-resistant flukes (TCBZ-R), morphological changes suggestive of apoptosis occur in cells undergoing meiosis or mitosis in the testis, ovary and vitelline follicles. In order to verify or refute the contention that efficacy of TCBZ treatment is associated with apoptosis in the reproductive organs of flukes, histological sections of TCBZ-S (Cullompton isolate) flukes and TCBZ-R (Sligo isolate) flukes were subjected to the TdT-mediated dUDP nick end labelling (TUNEL) in situ hybridisation method, a commercially available test specifically designed to label endonuclease-induced DNA strand breaks associated with apoptosis. Additionally, sections of in vivo-treated and untreated flukes originating from field outbreaks of suspected TCBZ-S and TCBZ-R fasciolosis were labelled by the TUNEL method. It was found that in treated TCBZ-S flukes, strong positive labelling indicating apoptosis was associated with morphologically abnormal cells undergoing mitosis or meiosis in the testis, ovary and vitelline follicles. Background labelling in the positive testis sections was attributed to heterophagy of cell debris by the sustentacular tissue. The triggering of apoptosis was probably related to failure of spindle formation at cell division, supporting the contention that TCBZ inhibits microtubule formation. In treated TCBZ-R (Sligo Type 1) flukes, and in treated flukes from field outbreaks of suspected TCBZ-R fasciolosis, no significant labelling was observed, while sections of fluke derived from a field case of fasciolosis where TCBZ resistance was not suspected were heavily labelled. Light labelling was associated with the

  12. Liver fluke-infested graft used for living-donor liver transplantation: case report and review of the literature.

    PubMed

    Capobianco, I; Frank, M; Königsrainer, A; Sipos, B; Menzel, M; Sturm, E; Nadalin, S

    2015-12-01

    Clonorchiasis is a cholangiopathy caused by foodborne trematode parasites, also known as liver flukes. Clonorchiasis is endemic in a wide geographical area extending from Eastern Europe to Southeast Asia. Infested hosts may remain asymptomatic for decades and consequently their liver can become available as a graft. To date, 20 liver transplantations with liver fluke-infested grafts have been reported in the literature. All of them occurred in Asian countries. We, here, report the first case to our knowledge in the Western world of living-donor liver transplantation (LDLT) with an Opisthorchis felineus-infested graft, and present a review of the literature. A 6-month-old girl with decompensated secondary biliary cirrhosis underwent an LDLT with a left lateral graft infested with O. felineus. After prompt diagnosis and adequate therapy, both donor and recipient had an uneventful postoperative course and long-term follow-up. Liver grafts infested with liver flukes do not pose a contraindication to liver donation from deceased or living donors, provided that a correct diagnosis and treatment are performed in a timely fashion. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Implementation of Health Behavior Education Concerning Liver Flukes among Village Health Volunteers in an Epidemic Area of Thailand.

    PubMed

    Kaewpitoon, Soraya J; Rujirakul, Ratana; Wakkuwattapong, Parichart; Matrakool, Likit; Tongtawee, Taweesak; Norkaew, Jun; Kujapun, Jirawoot; Kampangsri, Wilas; Kaewpitoon, Natthawut

    2016-01-01

    Liver fluke infection is associated with cholangiocarcinoma; the bile duct cancer found frequently in the northeast and north of Thailand. Prevention and control particularly requires health education and behavior change. This study aimed to improve health behavior among village health volunteers (VHV) regarding liver fluke exposure in an epidemic area. A quasi-experimental study was performed during July 2015 to January 2016 in Sang Kha district of Surin province, Thailand. A total of 67 VHVs underwent a health education program (HEP) and data were collected on knowledge, attitude, and practice (KAP) before and after participation for HEP 3 months with a pre-designed questionnaire. The Students paired T-test was used for comparisons of mean KAP levels before/after the intervention. The results revealed that knowledge (P-value=0.004), attitude (P-value=0.004), and practice level (P-value=0.000) were significantly improved after participation in the HBP. Attitude was significantly associated with knowledge (r=0.266, <0.05), and practice (r=0.348, <0.01) . The implementation of health education among VHVs is feasible and increases their KAP. This improvement should have potential in liver fluke prevention and control in local communities in rural Thailand.

  14. Fasciola hepatica - the pilot study of in vitro assessing immune response against native and recombinant antigens of the fluke.

    PubMed

    Bąska, Piotr; Zawistowska-Deniziak, Anna; Zdziarska, Anna M; Wasyl, Katarzyna; Wiśniewski, Marcin; Cywińska, Anna; Klockiewicz, Maciej; Januszkiewicz, Kamil; Wędrychowicz, Halina

    2013-12-01

    Fasciola hepatica is a liver fluke that infects 2.4 million of people and causes great economical loss in animal production. To date a 100% effective vaccine has not been developed and the disease is controlled by drug therapy. Great efforts are put into development of effective vaccine against parasite what is difficult since Fasciola spp. (like other helmints) during evolutionary process has developed sophisticated and efficient methods to evade immune response. During preliminary experiments it is convenient to use cell lines which are relatively cheap and allow for reproducible comparison of results between laboratories. We stimulated BOMA (bovine monocyte/macrophage cell line) and BOMAC (bovine macrophage cell line) with native or recombinant antigens of Fasciola hepatica and assessed IFN-γ, IL-4 and TNF-α level upon stimulation. We observed diminished secretion of proinflammatory TNF-α in LPS activated BOMA cells stimulated with Excretory/Secretory products of adult fluke (Fh-ES). We also observed greater changes in gene expression in LPS activated BOMA cells than in non activated BOMA cells upon stimulation using Fh-ES. The results show possibility of using cell lines for in vitro research of bovine immune response against liver fluke, although this model still requires validation and further characterization.

  15. Molecular evidence shows that the liver fluke Fasciola gigantica is the predominant Fasciola species in ruminants from Pakistan.

    PubMed

    Chaudhry, U; van Paridon, B; Shabbir, M Z; Shafee, M; Ashraf, K; Yaqub, T; Gilleard, J

    2016-03-01

    Fascioliasis is an important disease affecting livestock, with great costs to producers worldwide. It has also become a serious issue for human populations in some endemic areas as an emerging zoonotic infection. There are two Fasciola species of liver fluke responsible for this disease, which occur worldwide, Fasciola hepatica and Fasciola gigantica. Identifying these two species on the basis of adult or egg morphology requires specialist knowledge due to the similarity of characters, and may misidentify putative intermediate or hybrid forms. In this study we sequenced the internal transcribed spacer 2 (ITS-2) rDNA of liver flukes collected from multiple species of hosts from seven localities in the Punjab and Baluchistan provinces of Pakistan, to determine the distribution of these two species. All 46 flukes processed in this study, collected from seven sites, showed the rDNA ITS-2 genotype corresponding to F. gigantica, contradicting previous reports, based on adult and egg morphology, that both species are present in Pakistan, with F. hepatica being the more common.

  16. Liver fluke-induced hepatic oxysterols stimulate DNA damage and apoptosis in cultured human cholangiocytes.

    PubMed

    Jusakul, Apinya; Loilome, Watcharin; Namwat, Nisana; Haigh, W Geoffrey; Kuver, Rahul; Dechakhamphu, Somkid; Sukontawarin, Pradit; Pinlaor, Somchai; Lee, Sum P; Yongvanit, Puangrat

    2012-03-01

    Oxysterols are cholesterol oxidation products that are generated by enzymatic reactions through cytochrome P450 family enzymes or by non-enzymatic reactions involving reactive oxygen and nitrogen species. Oxysterols have been identified in bile in the setting of chronic inflammation, suggesting that biliary epithelial cells are chronically exposed to these compounds in certain clinical settings. We hypothesized that biliary oxysterols resulting from liver fluke infection participate in cholangiocarcinogenesis. Using gas chromatography/mass spectrometry, we identified oxysterols in livers from hamsters infected with Opisthorchis viverrini that develop cholangiocarcinoma. Five oxysterols were found: 7-keto-cholesta-3,5-diene (7KD), 3-keto-cholest-4-ene (3K4), 3-keto-cholest-7-ene (3K7), 3-keto-cholesta-4,6-diene (3KD), and cholestan-3β,5α,6β-triol (Triol). Triol and 3K4 were found at significantly higher levels in the livers of hamsters with O. viverrini-induced cholangiocarcinoma. We therefore investigated the effects of Triol and 3K4 on induction of cholangiocarcinogenesis using an in vitro human cholangiocyte culture model. Triol- and 3K4-treated cells underwent apoptosis. Western blot analysis showed significantly increased levels of Bax and decreased levels of Bcl-2 in these cells. Increased cytochrome c release from mitochondria was found following treatment with Triol and 3K4. Triol and 3K4 also induced formation of the DNA adducts 1,N(6)-etheno-2'-deoxyadenosine, 3,N(4)-etheno-2'-deoxycytidine and 8-oxo-7,8-dihydro-2'-deoxyguanosine in cholangiocytes. The data suggest that Triol and 3K4 cause DNA damage via oxidative stress. Chronic liver fluke infection increases production of the oxysterols Triol and 3K4 in the setting of chronic inflammation in the biliary system. These oxysterols induce apoptosis and DNA damage in cholangiocytes. Insufficient and impaired DNA repair of such mutated cells may enhance clonal expansion and further drive the change in

  17. Prevalence, risk factors and spatial analysis of liver fluke infections in Danish cattle herds.

    PubMed

    Olsen, Abbey; Frankena, Klaas; Bødker, Rene'; Toft, Nils; Thamsborg, Stig M; Enemark, Heidi L; Halasa, Tariq

    2015-03-15

    Fasciola hepatica, a trematode parasite (liver fluke), infects a wide range of host species causing fasciolosis. The disease is prevalent world-wide and causes considerable economic losses to the livestock industry. Fasciolosis is regarded as an emerging food-borne zoonosis. To promote awareness among farmers and to implement strategies to control the infection, this study examined the prevalence, spatial distribution and risk factors for F. hepatica infection in Danish cattle herds. A retrospective population based study was performed using meat inspection data of approximately 1.5 million cattle slaughtered in the period 2011 to 2013. Annual cumulative prevalence of recorded liver fluke findings was calculated for each year. Global and local spatial cluster analysis was used to identify and map spatial patterns of F. hepatica positive and negative herds to explore environmental indicators of infection. Herd level, trade and environmental risk factors were evaluated for association with infection using logistic regression. Herd infection status as predicted from the final risk factor model was compared with the observed status using heat maps to assess how well the model fitted the observed spatial pattern. During the investigated period (2011-2013), an increase in annual herd prevalence was noted (2011-25.6%; 2012-28.4%; 2013-29.3%). The spatial analysis suggested significant clustering of positive and negative herds. Presence of streams, wetlands and pastures on farms showed a significant association with the presence of infection in cattle herds. Buying animals from positive herds was a risk factor on conventional farms. Additionally, risk of being infected with F. hepatica was higher in non-dairy herds of medium size (≥30 and < 100) when compared to dairy and large (≥100) cattle herds. The observed spatial pattern could be reproduced by predictions of the risk factor model. This study showed an increase in annual herd level prevalence (2011 to 2013

  18. [A study on the fine structure of Clonorchus sinensis, a liver Fluke V. The mature spermatozoa

    PubMed

    Jeong, Kye Heon; Rim, Han Jong

    1984-06-01

    An ultrastructural study on the mature spermatozoa of Clonorchis sinensis was carried out. For this study, the liver flukes were collected from the livers of rabbits and rats artificially infected with the metacercariae obtained from the fresh water fish, Pseudorasbora parva. Six-month old worms were used. The collected liver flukes were washed with 0.85 percent saline solution and then immediately moved to cold 2 percent glutaraldehyde buffered with 0.l M Millonig's phosphate buffer (pH 7.4). The materials were dissected into appropriate pieces in the fixative about 30 minutes after beginning of the fixation. Two hours later the materials containing the seminal receptacle were rinsed several times with the buffer and were secondarily fixed with cold, buffered 1 percent osmium tetroxide for 2 hours. The fully fixed tissue blocks were dehydrated in a series of graded concentrations of acetone and were embedded in Epon 812 mixture. Thin sections obtained from LKB-5 ultramicrotome were stained with uranyl acetate and Reynold's lead citrate. Observations of the sections were carried out with JEM-100CX II electron microscope. In general, the mature sperm was long thread-like form with a sickle-shaped head. According to the longitudinal sectioned view of the sperm tail, the nucleus seemed to be spirally coiled and run a little far along the tail. The acrosome was not observed. The cytoplasm of the tail was biflagellated as usual in trematodes. Unlike other platyhelminth spermatozoa, the sperm tail of Clonorchis sinensis showed the [9+2] pattern in the microtubular arrangement. The mitochondria with poorly developed cristae were observed throughout the middle piece. The middle piece of the tail showed dull ladder or triangular shapes with the two flagella at the bottom. But, the principal piece of the tail was slightly flattened cylindrical shape with two flagella within the cytoplasm. The end piece was uniflagellated. It was not clearly identified whether the end piece

  19. Raw Fish Consuming Behavior Related to Liver Fluke Infection among Populations at Risk of Cholangiocarcinoma in Nakhon Ratchasima Province, Thailand.

    PubMed

    Chavengkun, Wasugree; Kompor, Pontip; Norkaew, Jun; Kujapun, Jirawoot; Pothipim, Mali; Ponphimai, Sukanya; Kaewpitoon, Soraya J; Padchasuwan, Natnapa; Kaewpitoon, Natthawut

    2016-01-01

    Opisthorchiasis is a health problem in rural communities of Thailand, particularly in the northeast and north regions. Therefore, this study aimed to investigate raw fish consuming behavior related to liver fluke infection among the population at risk for opisthorchiasis and cholangiocarcinoma (CCA). A cross-sectional descriptive study was conducted in Meuang Yang district, Nakhon Ratchasima province, northeast Thailand, between June and October 2015. Participants were screened for CCA, and samples who had a high score of CCA risk were purposively selected. A predesigned questionnaire was utilized to collect the data from all participants. X2-test was used for analysis of associations between demographic data and raw fish consumption. The results revealed that participants had past histories of stool examination (33.0%), liver fluke infection (21.0%), praziquantel use (24.0%), raw fish consumption (78.0%), relatives family consuming raw fish (73.0%), and relatives family with CCA (3.0%). Participants consumed several dished related to liver fluke infection, mainly raw fermented fish (13.0%), under smoked catfish (5.00%), raw pickled fish (4.00%), and raw spicy minced fish salad (3.00%). The most common types of cyprinoid fish were Barbodes gonionotus (39%), Hampala dispar (38%), Puntius brevis (37%), Cyclocheilichthys armatus (33%), Puntioplites proctozysron (32%), and Luciosoma bleekeri (30%), respectively. Participants had a low level of knowledge (mean=3.79, SD=0.74), moderate attitude (mean=7.31, SD=7.31) and practice (mean=38.64, SD=6.95) regarding liver fluke prevention and control. Demographic variables like age (>36 years old; X2-test=17.794, p-value=0.001), education (primary school; X2-test=18.952, p-value=0.001), marital status (married; X2-test=12.399, p-value=0.002), and income (<5,000 baht; X2-test=27.757, p-value=0.015) were significantly associated with raw fish consumption. This result indicates that the population had risk consumption for liver

  20. Population-Based Intervention for Liver Fluke Prevention and Control in Meuang Yang District, Nakhon Ratchasima Province, Thailand.

    PubMed

    Kompor, Pontip; Muang Karn, Rattikarn; Norkaew, Jun; Kujapun, Jirawoot; Photipim, Mali; Ponphimai, Sukanya; Chavengkun, Wasugree; Phong Paew, Somkiat; Kaewpitoon, Soraya; Rujirakul, Ratana; Wakhuwathapong, Parichart; Phatisena, Tanida; Eaksanti, Thawatchai; Joosiri, Apinya; Polsripradistdist, Poowadol; Padchasuwan, Natnapa; Kaewpitoon, Natthawut

    2016-01-01

    Opisthorchiasis is still a major health problem in rural communities of Thailand. Infection is associated with cholangiocarcinoma (CCA), which is found frequently in Thailand, particularly in the northeastern. Therefore, this study aimed to evaluate the effectiveness of health intervention in the population at risk for opisthorchiasis and CCA. A quasi-experimental study was conducted in Meuang Yang district, Nakhon Ratchasima province, northeastern Thailand, between June and October 2015. Participants were completed health intervention comprising 4 stations; 1, VDO clip of moving adult worm of liver fluke; 2, poster of life cycle of liver fluke; 3, microscopy with adult and egg liver fluke; and 4, brochure with the knowledge of liver fluke containing infection, signs, symptoms, related disease, diagnosis, treatment, prevention, and control. Pre-and-post-test questionnaires were utilized to collect data from all participants. Students paired t-tests were used to analyze differences between before and after participation in the health intervention. Knowledge (mean difference=-7.48, t=-51.241, 95% CI, -7.77, -7.19, p-value =0.001), attitude (mean difference=-9.07, t=-9.818, 95% CI=-10.9, -7.24, p-value=0.001), and practice (mean difference=-2.04, t=-2.688, 95% CI=-3.55, -0.53, p-value=0.008), changed between before and after time points with statistical significance. Community rules were concluded regarding: (1) cooked cyprinoid fish consumption; (2) stop under cooked cyprinoid fish by household cooker; (3) cooked food consumption; (4) hygienic defecation; (5) corrected knowledge campaign close to each household; (6) organizing a village food safety club; (7) and annual health check including stool examination featuring monitoring by village health volunteers and local public health officers. The results indicates that the present health intervention program was effective and easy to understand, with low cost and taking only a short time. Therefore, this program may

  1. Sensory exploitation and sexual conflict

    PubMed Central

    Arnqvist, Göran

    2006-01-01

    Much of the literature on male–female coevolution concerns the processes by which male traits and female preferences for these can coevolve and be maintained by selection. There has been less explicit focus on the origin of male traits and female preferences. Here, I argue that it is important to distinguish origin from subsequent coevolution and that insights into the origin can help us appreciate the relative roles of various coevolutionary processes for the evolution of diversity in sexual dimorphism. I delineate four distinct scenarios for the origin of male traits and female preferences that build on past contributions, two of which are based on pre-existing variation in quality indicators among males and two on exploitation of pre-existing sensory biases among females. Recent empirical research, and theoretical models, suggest that origin by sensory exploitation has been widespread. I argue that this points to a key, but perhaps transient, role for sexually antagonistic coevolution (SAC) in the subsequent evolutionary elaboration of sexual traits, because (i) sensory exploitation is often likely to be initially costly for individuals of the exploited sex and (ii) the subsequent evolution of resistance to sensory exploitation should often be associated with costs due to selective constraints. A review of a few case studies is used to illustrate these points. Empirical data directly relevant to the costs of being sensory exploited and the costs of evolving resistance is largely lacking, and I stress that such data would help determining the general importance of sexual conflict and SAC for the evolution of sexual dimorphism. PMID:16612895

  2. Evaluation of liver fluke recombinant cathepsin B-1 protease as a serodiagnostic antigen for human opisthorchiasis

    PubMed Central

    Sripa, Jittiyawadee; Brindley, Paul J.; Sripa, Banchob; Loukas, Alex; Kaewkes, Sasithorn; Laha, Thewarach

    2011-01-01

    A cathepsin B-like cysteine protease belonging to family C1 is abundantly expressed in the transcriptome and proteome of the carcinogenic liver fluke of humans, Opisthorchis viverrini. This enzyme is present in excretory/secretory (ES) products released by parasites cultured in vitro. This study evaluated the performance of recombinant O. viverrini cathepsin B1 (rOv-CB-1) as an antigen for immunodiagnosis of opisthorchiasis. The full length Ov-CB-1 cDNA was cloned and recombinant protein was produced in catalytically active form in Pichia pastoris. The recombinant Ov-CB-1 (rOv-CB-1) was affinity purified via nickel-NTA chromatography and tested in enzyme-linked immunosorbent assays (ELISA) with human sera from an opisthorchiasis endemic area. Sera from egg-positive O. viverrini infections produced a strong IgG antibody response to rOv-CB-1 both in ELISA and immunoblot analysis. The sensitivity and specificity of the ELISA test was 67% and 81%, respectively. These findings support the feasibility of using recombinant Ov-CB-1 in ELISA for the serodiagnosis of human opisthorchiasis. PMID:21704728

  3. Evaluation of liver fluke recombinant cathepsin B-1 protease as a serodiagnostic antigen for human opisthorchiasis.

    PubMed

    Sripa, Jittiyawadee; Brindley, Paul J; Sripa, Banchob; Loukas, Alex; Kaewkes, Sasithorn; Laha, Thewarach

    2012-03-01

    A cathepsin B-like cysteine protease belonging to family C1 is abundantly expressed in the transcriptome and proteome of the carcinogenic liver fluke of humans, Opisthorchis viverrini. This enzyme is present in excretory/secretory (ES) products released by parasites cultured in vitro. This study evaluated the performance of recombinant O. viverrini cathepsin B1 (rOv-CB-1) as an antigen for immunodiagnosis of opisthorchiasis. The full length Ov-CB-1 cDNA was cloned and recombinant protein was produced in catalytically active form in Pichia pastoris. The recombinant Ov-CB-1 (rOv-CB-1) was affinity purified via nickel-NTA chromatography and tested in enzyme-linked immunosorbent assays (ELISA) with human sera from an opisthorchiasis endemic area. Sera from egg-positive O. viverrini infections produced a strong IgG antibody response to rOv-CB-1 both in ELISA and immunoblot analysis. The sensitivity and specificity of the ELISA test was 67% and 81%, respectively. These findings support the feasibility of using recombinant Ov-CB-1 in ELISA for the serodiagnosis of human opisthorchiasis. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  4. The liver fluke Opisthorchis viverrini expresses nitric oxide synthase but not gelatinases.

    PubMed

    Prakobwong, Suksanti; Pinlaor, Porntip; Charoensuk, Lakhanawan; Khoontawad, Jarinya; Yongvanit, Puangrat; Hiraku, Yusuke; Pinlaor, Somchai

    2012-03-01

    Host-parasite interaction during infection with the liver fluke Opisthorchis viverrini plays an important role in opisthorchiasis-associated cholangiocarcinoma via nitric oxide (NO) production. Host cells induce nitric oxide synthase (NOS)-dependent DNA damage and secrete Ras-related C3 botulinum toxin substrate (Rac)1, heme oxygenase (HO)-1, and gelatinases (matrix metalloproteinase (MMP)2 and MMP9). We evaluated whether these enzymes are expressed in O. viverrini. Colocalization of NOS and Rac1 was most prominently detected on day 30 post-infection (p.i.) in the gut, reproductive organ, eggs, acetabular and tegument. Expression of HO-1, an antioxidative enzyme, increased in a similar pattern to NOS, but was not present in the tegument. The levels of nitrate/nitrite, end products of NO, and ferric reducing antioxidant capacity, an indicator of antioxidant enzyme capacity, in parasite homogenates were highest on day 30 p.i. and then decreased on day 90 p.i. In contrast, zymography revealed that MMP2 and MMP9 were not present in parasite homogenates at all time points. In conclusion, O. viverrini induces NOS expression and NO production, but does not express gelatinases. The study may provide basic information and an insight into drug design for prevention and/or intervention approaches against O. viverrini infection. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  5. Genetic and infective diversity of the liver fluke Fasciola hepatica (Trematoda: Digenea) from Cuba.

    PubMed

    Vázquez, A A; Lounnas, M; Sánchez, J; Alba, A; Milesi, A; Hurtrez-Boussès, S

    2016-11-01

    In this study we present the first approach to exploration of the genetic diversity of Cuban Fasciola hepatica populations using microsatellite markers, coupled with observed prevalence in slaughterhouses. Nine populations of flukes recovered from cows and buffalos were studied in the central-western region of Cuba. The observed infection rates of definitive hosts (bovines) were 70-100% in most cases. An important amount of polymorphism was found in the four loci explored. However, no apparent genetic differences were found between populations from different provinces or bovine species. The absence of deviations from Hardy-Weinberg equilibrium suggests a high rate of cross-fertilization between F. hepatica individuals. This result was confirmed when all multilocus genotypes were tested for clonal reproduction and only four individuals differed statistically (P sex< 0.05). High values of expected heterozygosity coupled with highly probable mixing among strains make the metapopulation genetically diversified but similar in terms of certain alleles (low F ST values). These results suggest a close relationship between parasite diversity and cattle management in Cuba. Our findings should be taken into consideration by veterinary authorities to help mitigate fasciolosis transmission.

  6. Chromosomes and karyotype analysis of a liver fluke, Opisthorchis viverrini, by scanning electron microscopy.

    PubMed

    Kaewkong, Worasak; Choochote, Wej; Kanla, Pipatpong; Maleewong, Wanchai; Intapan, Pewpan M; Wongkham, Sopit; Wongkham, Chaisiri

    2012-09-01

    Opisthorchis viverrini, a human liver fluke, has been categorized as the carcinogenic organism according to the strong association with carcinogenesis of cholangiocarcinoma (CCA). The infection of this food-borne parasite is a major impact on the health of humans, especially CCA patients in the northeast of Thailand. Taxonomy, morphology, epidemiology and molecular study of O. viverrini have been publicized increasingly but the precise karyotypic study is still incomplete. In this study, the chromosomes of O. viverrini were prepared from the testes of adult worms retrieved from metacercariae infected-hamsters. The chromosomes of O. viverrini were identified in haploid (n=6) meiotic metaphase and in diploid (2n=12) mitotic metaphase by light microscopy. The chromosome number, length and nomenclature of each chromosome were determined by scanning electron microscopy. The six chromosomes consist of one large-sized metacentric, one medium-sized metacentric, two small-sized metacentric, one small-sized submetacentric and one small-sized acrocentric chromosomes with the lengths of 2.84±0.03, 2.12±0.10, 1.71±0.13, 1.44±0.04, 1.23±0.03 and 0.84±0.13 μm, respectively. This is the first karyotype analysis of O. viverrini with defined complete nomenclature.

  7. Clinical changes caused by the liver fluke Metorchis conjunctus in cats.

    PubMed

    Watson, T G; Croll, N A

    1981-11-01

    Cats infected with metacercariae of the fluke Metorchis conjunctus were followed clinically through their infection. Cats given 200 metacercariae showed few symptoms. All the cats passed ova on the 17th day. Three hundred metacercariae caused diarrhea, icterus, discolored urine, green feces and eosinophilia after 18 to 21 days. Eosinophilia, leucine aminopeptidase and alanine aminotransferase were elevated and remain the best indicators for metorchiasis. The hematological and serological abnormalities resolved rapidly and were absent from cats with chronic infection. Acute lesions (less than 32 days) were confined to the biliary trees with extensive epithelial exfoliation, fibrosis, and pus from necrosis, tissue feeding by the worms and pressure atrophy. Chronic infections (32 to 150 days) caused hyperplasia of the bile epithelium, proliferation of connective tissues, and fibrosis of the perilobular areas. Intense eosinophilic infiltrates were replaced by mononuclear cells. Granuloma formation around an ovum was seen in one cat 719 days after infection. Adult worms established preferentially in the left lateral lobe and never in the caudal lobe. No gall bladder involvement was found even in heavy infections.

  8. Sequencing and characterization of the complete mitochondrial genome from the pancreatic fluke Eurytrema pancreaticum (Trematoda: Dicrocoeliidae).

    PubMed

    Chang, Qiao-Cheng; Liu, Guo-Hua; Gao, Jun-Feng; Zheng, Xu; Zhang, Yan; Duan, Hong; Yue, Dong-Mei; Fu, Xue; Su, Xin; Gao, Yuan; Wang, Chun-Ren

    2016-01-15

    The trematode Eurytrema pancreaticum is a parasite of ruminant pancreatic and bile ducts, and also occasionally infects humans, causing eurytremiasis. In spite of it being a common fluke of cattle and sheep in endemic regions, little is known about the genomic resources of the parasite. We sequenced the complete mitochondrial (mt) genome of E. pancreaticum. It is 15,031 bp in size, and encodes 36 genes: 12 protein-coding genes, two ribosomal RNA genes, and 22 transfer RNA genes. The E. pancreaticum mt gene order is the same as that of Dicrocoelium chinensis and Dicrocoelium dendriticum, and all genes are transcribed in the same direction. Phylogenetic analysis based on the concatenated amino acid sequences of 12 protein-coding genes by Bayesian inference shows that E. pancreaticum is closely related to D. chinensis and other members of the family Dicrocoeliidae with strong posterior probability support. The E. pancreaticum mt genome should prove to be a useful resource for comparative mt genomic studies of digenetic trematodes, and will provide a rich source of DNA markers for studies into the systematics, epidemiology, and population genetics of this parasite and other digenean trematodes. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Lung fluke (Paragonimus africanus) infects Nigerian red-capped mangabeys and causes respiratory disease

    PubMed Central

    Friant, Sagan; Brown, Kelsey; Saari, Mason T.; Segel, Nicholas H.; Slezak, Julia; Goldberg, Tony L.

    2015-01-01

    Eggs of the lung fluke genus Paragonimus were detected in red-capped mangabeys (Cercocebus torquatus) in Nigeria. We assess the role of these primates as potential sylvatic hosts and the clinical effects of the parasite on monkeys. DNA sequenced from eggs in feces were 100% identical in the ITS2 region to Paragonimus africanus sequences from humans in Cameroon. Paragonimus-positive monkeys coughed more than uninfected monkeys. Experimental de-worming led to reduction in parasite intensity and a corresponding reduction of coughing to baseline levels in infected monkeys. This report provides the first evidence of Paragonimus sp. in C. torquatus, of P. africanus in Nigerian wildlife, and the first molecular evidence of the parasite in African wildlife. Coughing, sometimes interpreted as a communication behavior in primates, can actually indicate infection with lung parasites. Observations of coughing in primates may, in turn, provide a useful mechanism for surveillance of Paragonimus spp, which are re-emerging human pathogens, in wildlife reservoirs. PMID:26543803

  10. Lung fluke (Paragonimus africanus) infects Nigerian red-capped mangabeys and causes respiratory disease.

    PubMed

    Friant, Sagan; Brown, Kelsey; Saari, Mason T; Segel, Nicholas H; Slezak, Julia; Goldberg, Tony L

    2015-12-01

    Eggs of the lung fluke genus Paragonimus were detected in red-capped mangabeys (Cercocebus torquatus) in Nigeria. We assess the role of these primates as potential sylvatic hosts and the clinical effects of the parasite on monkeys. DNA sequenced from eggs in feces were 100% identical in the ITS2 region to Paragonimus africanus sequences from humans in Cameroon. Paragonimus-positive monkeys coughed more than uninfected monkeys. Experimental de-worming led to reduction in parasite intensity and a corresponding reduction of coughing to baseline levels in infected monkeys. This report provides the first evidence of Paragonimus sp. in C. torquatus, of P. africanus in Nigerian wildlife, and the first molecular evidence of the parasite in African wildlife. Coughing, sometimes interpreted as a communication behavior in primates, can actually indicate infection with lung parasites. Observations of coughing in primates may, in turn, provide a useful mechanism for surveillance of Paragonimus spp, which are re-emerging human pathogens, in wildlife reservoirs.

  11. Freshwater mussels (Anodonta anatina) reduce transmission of a common fish trematode (eye fluke, Diplostomum pseudospathaceum).

    PubMed

    Gopko, M; Mironova, E; Pasternak, A; Mikheev, V; Taskinen, J

    2017-08-02

    Recent results suggest that bivalves can play an important role in restraining the spread of various aquatic infections. However, the ability of mussels to remove free-living stages of macroparasites and reduce their transmission is still understudied, especially for freshwater ecosystems. We investigated the influence of the common freshwater mussel (Anodonta anatina) on the transmission of a trematode (eye fluke, Diplostomum pseudospathaceum), which frequently infects fish in farms and natural habitats. In our experiments, mussels caused a significant decrease (P < 0·001) in the abundance of trematode free-living stages, from 6520 to 1770 cercariae L-1 on average (about 4-fold in 2 h). Individual clearance rates of mussels were 0·6‒3·7 L per hour (mean 1·9). These tests were followed by experimental infections of rainbow trout (Oncorhynchus mykiss) with different doses of D. pseudospathaceum cercariae in the presence or absence of mussels. Exposure of fish to cercariae in the presence of mussels significantly (P < 0·05) reduced the infection intensities in fish (by 30-40%) at all exposure doses. Our results indicate that freshwater bivalves can markedly reduce local cercariae densities and could be useful in mitigation of trematodoses harmful to fish farming.

  12. Heterophysiasis, an intestinal fluke infection of man and vertebrates transmitted by euryhaline gastropods and fish

    NASA Astrophysics Data System (ADS)

    Taraschewski, H.

    1984-03-01

    Heterophyes heterophyes, agent of human heterophyiasis in the Near East, is transmitted in marine lagoons and saline inland waters, where the euryhaline intermediate hosts are abundant. In Egypt, mullets, the predominant second intermediate hosts, are customarily consumed raw; thus man becomes infected easily. Symptoms of human infections are usually considered mild. Mullets do not seem to be affected by the metacercariae encysted in the muscles, whereas the growth of the snail host Pirenella conica was found to be enhanced due to the infestation by the trematodes. In laboratory experiments, the flukes were found to be well developed in dogs, foxes and cats, but failed to reach sexual maturity in several other potentially piscivorous mammals and birds. In nature, dogs probably serve as the major reservoir hosts. Heterophyiasis is most prevalent in the Nile Delta, a huge brackish water area which is densely populated by humans and, consequently, also by dogs and cats. In the Far East, besides Heterophyes nocens, several other heterophysids with marine or fresh-water life-cycles are known to infect humans.

  13. Kinetics independent spectrometric analysis using non-linear calibration modelling and exploitation of concentration gradients generated by a flow-batch system for albumin and total protein determination in blood serum.

    PubMed

    Souza, Margarida C; Martins, Valdomiro L; Almeida, Luciano F; Pessoa Neto, Osmundo D; Gaião, Edvaldo N; Araujo, Mario Cesar U

    2010-08-15

    An automatic method for kinetics independent spectrometric analysis is proposed in this study. It uses a non-linear calibration model that explores concentration gradients generated by a flow-batch analyser (FBA) for the samples, dye, and the single standard solution. The procedure for obtaining the gradients of the dye and standard solution is performed once at the beginning of analysis. The same procedure is applied thereafter for each sample. For illustration, the proposed automatic methodology was applied to determine total protein and albumin in blood serum by using the Biuret and Bromocresol Green (BCG) methods. The measurements were made by using a laboratory-made photometer based on a red and green bicolour LED (Light-Emitting Diode) and a phototransistor, coupled to a "Z" form flow cell. The sample throughput was about 50 h(-1) for albumin and 60 h(-1) for total protein, consuming about 7 microL of sample, 2.6 mL of BCG and 1.2 mL of biuret reagents for each determination. Applying the paired t-test for results from the proposed analyser and the reference method, no statistic differences at 95% confidence level were found. The absolute standard deviation was usually smaller than 0.2 g dL(-1). The proposed method is valuable for the determination of total protein and albumin; and can also be used in other determinations where kinetic effects may or may not exist.

  14. Identification of Fasciola flukes in Thailand based on their spermatogenesis and nuclear ribosomal DNA, and their intraspecific relationships based on mitochondrial DNA.

    PubMed

    Chaichanasak, Pannigan; Ichikawa, Madoka; Sobhon, Prasert; Itagaki, Tadashi

    2012-12-01

    We analyzed 147 Fasciola flukes obtained from cattle in Thailand based on their spermatogenetic ability, and nuclear ribosomal internal transcribed spacer 1 (ITS1) and mitochondrial nicotiamide adenine dinucleotide dehydrogenase subunit 1 (ND1) genes as molecular markers. One hundred twenty-eight flukes, which had abundant sperm in their seminal vesicles (spermic) and showed the PCR-RFLP pattern of F. gigantica in the ITS1, were accurately identified as F. gigantica. The other 19 flukes that had no sperm in their seminal vesicles were aspermic Fasciola sp. with the RFLP patterns identical to that of F. gigantica. Twenty-nine ND1 haplotypes (Fg-ND1-Thai 2-30) were distinguished in the 128 F. gigantica flukes and were divided into haplotypes unique to Thailand and those common to other countries, suggesting the possibility that ancestral haplotypes were introduced into Thailand. Three haplotypes (Fg-ND1-Thai 7, 9 and 27) appeared to be the major haplotypes found in F. gigantica from Thailand. Only one haplotype (Fg-ND1-Thai 1) was found in the 19 aspermic Fasciola sp. flukes obtained from geographical regions, and the nucleotide sequence of Fg-ND1-Thai 1 was identical to that of the aspermic Fasciola sp. from Japan, Korea, China, Vietnam and Myanmar, suggesting that they were descendants with a common provenance and expanded to these countries in the relatively recent past.

  15. The Exploitation of Black Athletes.

    ERIC Educational Resources Information Center

    Edwards, Harry

    1983-01-01

    Colleges and universities have not up held their end of the bargain with athletes, exploiting a disproportionate number of talented Black athletes by not providing the kind of education the students sought or needed and by applying rigid academic standards for eligibility. (MSE)

  16. Sequence analysis of ribosomal and mitochondrial genes of the giant liver fluke Fascioloides magna (Trematoda: Fasciolidae): intraspecific variation and differentiation from Fasciola hepatica.

    PubMed

    Králová-Hromadová, Ivica; Spakulová, Marta; Horácková, Eva; Turceková, Ludmila; Novobilský, Adam; Beck, Relja; Koudela, Bretislav; Marinculić, Albert; Rajský, Dusan; Pybus, Margo

    2008-02-01

    Complete sequences of ribosomal and mitochondrial genes of the giant liver fluke Fascioloides magna are presented. In particular, small subunit (18S) and internal transcribed spacers (ITS1 and ITS2) of the ribosomal gene (rDNA), as well as cytochrome c oxidase subunit I (cox1) and nicotinamide dehydrogenase subunit I (nad1) of the mitochondrial DNA (mtDNA), were analyzed. The 18S and ITS sequences were compared with previously published sequences of the liver fluke Fasciola hepatica. Fixed interspecific genetic differences were determined that allow molecular differentiation of F. magna and F. hepatica using either the PCR-RFLP method or PCR amplification of species-specific DNA regions. Additionally, intraspecific sequence polymorphism of the complete cox1 and nad1 mitochondrial genes in geographically distinct F. magna populations was determined. Based on the sequence divergences, short (< 500 bp) variable regions suitable for broader biogeographical studies of giant liver fluke were designed.

  17. Host specificity of a parasitic fluke: is Posthodiplostomum minimum a centrarchid-infecting generalist or specialist?

    PubMed

    Lane, Beth; Spier, Timothy; Wiederholt, Julia; Meagher, Shawn

    2015-02-01

    Parasite host specificity has important implications for species diversity estimates, food web dynamics, and host shifts. "White grub" is the metacercaria stage of a fluke ( Posthodiplostomum minimum ) that occurs in many fish species, but no attempt has been made to quantify variation in host use by this worm. Here we used 2 approaches to evaluate host specificity within the strain that infects centrarchids ( P. minimum centrarchi). First, we measured parasite loads in 2 centrarchid hosts, bluegill ( Lepomis macrochirus ) and white crappie ( Pomoxis annularis ), from Spring Lake in McDonough County, Illinois. We found that infection levels differed significantly between these hosts. Prevalence in bluegill was 100% and the median intensity was 940 metacercariae, but only 57% of white crappie were infected (median intensity = 4). Site specificity of white grub also differed significantly between the 2 hosts. In bluegills, kidneys were most heavily infected, whereas in white crappies, livers harbored the most worms. We also performed a literature survey of P. minimum prevalence estimates from 14 centrarchid species from other localities. We calculated the mean white grub prevalence for each host species and used this to calculate STD*, a quantitative index of host specificity. STD* was 1.33, significantly closer to the value for a specialist (STD* = 1.00) than a generalist (STD* = 2.00). This reflects the fact that P. minimum prevalence is higher in Lepomis species than it is in centrarchids outside this genus. These data show that P. minimum centrarchi specializes on Lepomis species, but the causes of this specialization are unknown. This worm may be a single species that differs in host use due to ecological or physiological host differences, or it may be a complex of species that vary in host use for similar reasons. Genetic data are required to evaluate these possibilities.

  18. Circulating miR-192 in liver fluke-associated cholangiocarcinoma patients: a prospective prognostic indicator.

    PubMed

    Silakit, Runglawan; Loilome, Watcharin; Yongvanit, Puangrat; Chusorn, Porncheera; Techasen, Anchalee; Boonmars, Thidarut; Khuntikeo, Narong; Chamadol, Nittaya; Pairojkul, Chawalit; Namwat, Nisana

    2014-12-01

    This study aimed to investigate the miR-192 levels in patients' sera of liver fluke-associated cholangiocarcinoma (CCA) for a prospective prognostic indicator. MicroRNA polymerase chain reaction (PCR) array was performed using pooled serum samples from 11 CCA patients and nine healthy subjects. Selected miRNAs were verified for the differential levels in both sera and tumor tissues (of patients and Opisthorchis viverrini (Ov)-induced CCA model) using TaqMan miRNA expression assay. Our results demonstrated that miR-192 was significantly higher in the serum of CCA patients than that in healthy subjects giving a sensitivity of 74% and specificity of 72% (area under the curve [AUC] = 0.803; 95% confidence interval [CI], 0.708-0.897, P < 0.0001). Serum miR-192 examined in Ov infected subjects and subjects with periductal fibrosis were increased but not statistically significantly when compared with healthy subjects. High levels of serum miR-192 were significantly correlated with lymph node metastasis (P = 0.047) and shorter survival compared with individuals with low levels of serum miR-192 (hazard ratio [HR] 2.076, 95% CI 1.004-4.291, P = 0.049). We also found that the expression levels of miR-192 appeared to be elevated in both CCA tissues of patients and in Ov-induced CCA tissues of a hamster model. This finding indicates that elevated levels of miR-192 may be involved in CCA genesis and have a potential utility as a noninvasive prognostic indicator for CCA patients. © 2014 Japanese Society of Hepato-Biliary-Pancreatic Surgery.

  19. Transcriptomic responses of water buffalo liver to infection with the digenetic fluke Fasciola gigantica.

    PubMed

    Zhang, Fu-Kai; Zhang, Xiao-Xuan; Elsheikha, Hany M; He, Jun-Jun; Sheng, Zhao-An; Zheng, Wen-Bin; Ma, Jian-Gang; Huang, Wei-Yi; Guo, Ai-Jiang; Zhu, Xing-Quan

    2017-02-01

    Fasciola gigantica, the tropical liver fluke, infects buffaloes in Asian and African countries and causes significant economic losses and poses public health threat in these countries. However, little is known of the transcriptional response of buffaloes to infection with F. gigantica. The objective of the present study was to perform the first transcriptomic analysis of buffalo liver infected by F. gigantica. Understanding the mechanisms that underpin F. gigantica infection in buffaloes will contribute to our ability to control this parasite. We challenged buffaloes with 500 viable F. gigantica metacercariae and collected liver samples through a time course at 3, 42 and 70 days post-infection (dpi). Then, we performed gene expression analysis on liver samples using RNA sequencing (RNA-Seq) Illumina technology and confirmed the RNA-Seq data by quantitative RT-PCR analysis. Totals of 496, 880 and 441 differentially expressed transcripts were identified in the infected livers at 3, 42 and 70 dpi, respectively. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that transcriptional changes in the liver of infected buffaloes evolve over the course of infection. The predominant response of buffaloes to infection was mediated by certain pathways, such as MHC antigen processing and presentation, Toll-like receptor 4 (TLR4), transforming growth factor beta (TGF-β), and the cytochrome P450. Hepatic drug metabolizing enzymes and bile secretion were also affected. Fasciola gigantica can induce statistically significant and biologically plausible differences in the hepatic gene expression of infected buffaloes. These findings provide new insights into the response of buffaloes to F. gigantica over the course of infection, which may be useful in determining pathways that can modulate host-parasite interaction and thus potentially important for clearance of the parasite.

  20. A combination of liver fluke infection and traditional northeastern Thai foods associated with cholangiocarcinoma development.

    PubMed

    Sriraj, Pranee; Boonmars, Thidarut; Aukkanimart, Ratchadawan; Songsri, Jiraporn; Sripan, Panupan; Ratanasuwan, Panaratana; Boonjaraspinyo, Sirintip; Wongchalee, Nadchanan; Laummaunwai, Porntip

    2016-10-01

    Opisthorchis viverrini infection is one of the risk factors for cholangiocarcinoma (CCA) in northeast Thailand, a region with one of the highest reported incidence rates of CCA. The traditional practice of eating raw fish, repeated exposure to liver flukes, and consumption of nitrosamine-contaminated food are major risk factors for CCA. So far, there have been no reports about which northeastern traditional dishes may be involved in CCA development. The present study, thus, investigated the effects of traditional foods. It focused specifically on the consumption of fermented foods in combination with O. viverrini infection in hamsters. Syrian hamsters were divided into six groups: (i) normal hamsters, (ii) O. viverrini infection only and (iii)-(vi) O. viverrini infection plus fermented foods (pla som-fish fermented for 1 day), som wua-fermented beef, som phag-fermented vegetables, and pla ra-fish fermented for 6 months. Syrian hamster livers were used for analysis of histopathological changes through hematoxylin and eosin; Sirius Red; and immunohistostaining for cytokeratin-19, proliferating cell nuclear antigen, and CA19-9. Hamster sera were used for liver and kidney function tests. Results of all O. viverrini-infected groups and fermented food groups showed that histopathological changes consisted primarily of aggregations of inflammatory cells surrounding the hepatic bile duct, especially at the hilar region. However, there was a difference in virulence. Interestingly, aggregations of inflammatory cells, new bile duct formation, and fibrosis were observed in subcapsular hepatic tissue, which correlated to positive immunohistochemical staining and increased liver function test. The present study suggests that fermented food consumption can exacerbate cholangitis and cholangiofibrosis, which are risk factors for cholangiocarcinoma-associated opisthorchiasis.

  1. Adulticidal and larvicidal efficacy of some medicinal plant extracts against tick, fluke and mosquitoes.

    PubMed

    Bagavan, A; Kamaraj, C; Elango, G; Abduz Zahir, A; Abdul Rahuman, A

    2009-12-23

    The adulticidal and larvicidal effect of indigenous plant extracts were investigated against the adult cattle tick Haemaphysalis bispinosa Neumann, 1897 (Acarina: Ixodidae), sheep fluke Paramphistomum cervi Zeder, 1790 (Digenea: Paramphistomatidae), fourth instar larvae of malaria vector, Anopheles subpictus Grassi and Japanese encephalitis vector, Culex tritaeniorhynchus Giles (Diptera: Culicidae). The aim of this study was to evaluate the toxic effect of leaf hexane, chloroform, ethyl acetate, acetone and methanol extracts of Annona squamosa L., Centella asiatica (L.) Urban, Gloriosa superba L., Mukia maderaspatensis (L.) M.Roem, Pergularia daemia (Forsk.) Chiov. and Phyllanthus emblica L. were exposed to different concentrations. All plant extracts showed moderate toxic effect on parasites after 24h of exposure; however, the highest mortality was found in leaf hexane extract of A. squamosa, methanol extracts of G. superba and P. emblica against H. bispinosa (LC(50)=145.39, 225.57 and 256.08ppm); methanol extracts of C. asiatica, G. superba, P. daemia and P. emblica against P. cervi (LC(50)=77.61, 60.16, 59.61, and 60.60ppm); acetone, ethyl acetate extracts of A. squamosa, methanol extract of C. asiatica, acetone extracts of G. superba, ethyl acetate, hexane and methanol extracts of P. daemia against A. subpictus (LC(50)=17.48, 18.60, 26.62, 18.43, 34.06, 13.63, and 50.39ppm); and chloroform, ethyl acetate extracts of A. squamosa, ethyl acetate extract of P. daemia, ethyl acetate and methanol extracts of P. emblica against C. tritaeniorhynchus (LC(50)=63.81, 60.01, 31.94, 69.09, and 54.82ppm), respectively. These results demonstrate that methanol extracts of C. asiatica, G. superba, P. daemia and P. emblica extracts may serve as parasites control even in their crude form.

  2. Enzyme-linked immunosorbent assay for diagnosis of Amphimerus spp. liver fluke infection in Humans.

    PubMed

    Cevallos, William; Calvopiña, Manuel; Nipáz, Victoria; Vicente-Santiago, Belén; López-Albán, Julio; Fernández-Soto, Pedro; Guevara, Ángel; Muro, Antonio

    2017-05-01

    Amphimerus spp. is a liver fluke that infects humans and domestic animals. It is highly prevalent in some Ecuadorian communities. Currently, diagnosis is based on the microscopic observation of eggs in faeces, but this has variable sensitivity. More sensitive methods are needed for diagnostic testing. The main objective of this work was to develop an enzyme-linked immunosorbent assay (ELISA) using crude antigens from Amphimerus spp. adult worms to detect anti-Amphimerus IgG in human sera. Crude somatic antigens were obtained from adult Amphimerus spp. worms. Human sera from 119 patients were tested: 48 from individuals with a confirmed Amphimerus spp. infection, 78 from non-infected Ecuadorians living in the endemic region, 60 from persons living in non-endemic areas (20 Ecuadorians, 20 Europeans, and 20 Africans), and 33 who had other parasitic and non-parasitic infections. Results were analysed using the receiver-operator characteristic (ROC) curve analysis with an area under curve (AUC) value of 0.967. The accuracy of the ELISA was high. The sensitivity was 85.0% [95% confidence interval (CI): 80.3-89.7%] and the specificity was 71.0% (95% CI: 65.2-76.8%). Some cross reactivity was detected against Paragonimus mexicanus, Fasciola hepatica, Schistosomiasis, Taenia solium, Strongyloides stercoralis, Mansonella spp., and Vampirolepis nana. We have developed the first ELISA technique that detects anti-Amphimerus IgG in human sera with good sensitivity, repeatability and reproducibility. However, more specific antigens are needed to further enhance performance of this assay. Regardless, this ELISA test could be useful for early diagnosis and prompt treatment of human Amphimerus spp. infections.

  3. Identification and characterization of protein 14-3-3 in carcinogenic liver fluke Opisthorchis viverrini.

    PubMed

    Kafle, Alok; Puchadapirom, Pranom; Plumworasawat, Sirikanya; Dontumprai, Rieofarng; Chan-On, Waraporn; Buates, Sureemas; Laha, Thewarach; Sripa, Banchob; Suttiprapa, Sutas

    2016-10-27

    Protein 14-3-3s are abundant phospho-serine/threonine binding proteins, which are highly conserved among eukaryotes. Members of this protein family mediate metabolism and signal transduction networks through binding to hundreds of other protein partners. Protein 14-3-3s have been studied in other species of parasitic helminthes, but little is known about this protein in the carcinogenic liver fluke Opisthorchis viverrini. In this study, we identified and characterized protein 14-3-3s of O. viverrini. Seven protein 14-3-3 encoded sequences were retrieved from the O. viverrini genome database. Multiple alignment and phylogenetic analysis were performed. Two isoforms (protein 14-3-3 zeta and protein 14-3-3 epsilon) that have been previously found in the excretory-secretory (ES) products of O. viverrini were produced as recombinant protein in E. coli and the proteins were then used to immunize mice to obtain specific antibodies. Western blot analysis showed that both proteins were detected in all obtainable developmental stages of O. viverrini and the ES products. Immunolocalization revealed that both isoforms were expressed throughout tissues and organs except the gut epithelium. The highest expression was observed in testes especially in developing spermatocytes, suggesting their role in spermatogenesis. Prominent expression was also detected on tegumental surface of the parasite and on epical surface of bile duct epithelium indicates their additional role in host-parasite interaction. These findings indicate that protein 14-3-3s play important role in the life cycle of the parasite and might be involved in the pathogenesis of O. viverrini infection.

  4. Enzyme-linked immunosorbent assay for diagnosis of Amphimerus spp. liver fluke infection in Humans

    PubMed Central

    Cevallos, William; Calvopiña, Manuel; Nipáz, Victoria; Vicente-Santiago, Belén; López-Albán, Julio; Fernández-Soto, Pedro; Guevara, Ángel; Muro, Antonio

    2017-01-01

    BACKGROUND Amphimerus spp. is a liver fluke that infects humans and domestic animals. It is highly prevalent in some Ecuadorian communities. Currently, diagnosis is based on the microscopic observation of eggs in faeces, but this has variable sensitivity. More sensitive methods are needed for diagnostic testing. OBJECTIVE The main objective of this work was to develop an enzyme-linked immunosorbent assay (ELISA) using crude antigens from Amphimerus spp. adult worms to detect anti-Amphimerus IgG in human sera. METHODS Crude somatic antigens were obtained from adult Amphimerus spp. worms. Human sera from 119 patients were tested: 48 from individuals with a confirmed Amphimerus spp. infection, 78 from non-infected Ecuadorians living in the endemic region, 60 from persons living in non-endemic areas (20 Ecuadorians, 20 Europeans, and 20 Africans), and 33 who had other parasitic and non-parasitic infections. PRINCIPAL FINDINGS Results were analysed using the receiver-operator characteristic (ROC) curve analysis with an area under curve (AUC) value of 0.967. The accuracy of the ELISA was high. The sensitivity was 85.0% [95% confidence interval (CI): 80.3-89.7%] and the specificity was 71.0% (95% CI: 65.2-76.8%). Some cross reactivity was detected against Paragonimus mexicanus, Fasciola hepatica, Schistosomiasis, Taenia solium, Strongyloides stercoralis, Mansonella spp., and Vampirolepis nana. MAIN CONCLUSIONS We have developed the first ELISA technique that detects anti-Amphimerus IgG in human sera with good sensitivity, repeatability and reproducibility. However, more specific antigens are needed to further enhance performance of this assay. Regardless, this ELISA test could be useful for early diagnosis and prompt treatment of human Amphimerus spp. infections. PMID:28443982

  5. Multiple origins of European populations of the giant liver fluke Fascioloides magna (Trematoda: Fasciolidae), a liver parasite of ruminants.

    PubMed

    Králová-Hromadová, Ivica; Bazsalovicsová, Eva; Stefka, Jan; Spakulová, Marta; Vávrová, Silvia; Szemes, Tomáš; Tkach, Vasyl; Trudgett, Alan; Pybus, Margo

    2011-03-01

    The giant liver fluke, Fascioloides magna, a liver parasite of free-living and domestic ruminants of Europe and North America, was analysed in order to determine the origin of European populations and to reveal the biogeography of this originally North American parasite on the European continent. The variable fragments of the mitochondrial cytochrome c oxidase subunit I (cox1; 384bp) and nicotinamide dehydrogenase subunit I (nad1; 405bp) were used. Phylogenetic trees and haplotype networks were constructed and the level of genetic structuring was evaluated using population genetic tools. In F. magna individuals originating from all European foci of infection (Italy, Czech Republic and Danube floodplain forests involving the territories of Slovakia, Hungary and Croatia) and from four of five major North American enzootic areas, 16 cox1 and 18 nad1 haplotypes were determined. The concatenated sequence set produced 22 distinct haplotypes. The European fluke populations were less diverse than those from North America in that they contained proportionately fewer haplotypes (eight), while a more substantial level of genetic diversity and a greater number of haplotypes (15) were recorded in North America. Only one haplotype was shared between the European (Italy) and North American (USA/Oregon and Canada/Alberta) flukes, supporting a western North American origin of the Italian F. magna population. Haplotypes found in Italy were distinct from those determined in the remaining European localities which indicates that introduction of F. magna to the European continent occurred more than once. In the Czech focus of infection, a south-eastern USA origin was revealed. Identical haplotypes, common to parasites from the Czech Republic and from an expanding focus in Danube floodplain forests, implies that the introduction of F. magna to the Danube region came from an already established Czech focus of infection. Copyright © 2010 Australian Society for Parasitology Inc. Published

  6. LIFE CYCLE, HOST UTILIZATION, AND ECOLOGICAL FITTING FOR INVASIVE LANCET LIVER FLUKE, DICROCOELIUM DENDRITICUM, EMERGING IN SOUTHERN ALBERTA, CANADA.

    PubMed

    van Paridon, Bradley; Gilleard, John S; Colwell, Douglas D; Goater, Cameron P

    2017-02-17

    The expansion of parasite distributions outside of their native host and geographical ranges has occurred repeatedly over evolutionary time. Contemporary examples include emerging infectious diseases (EID's), many of which pose threats to human, domestic animal, and wildlife populations. Theory predicts that parasites with complex life cycles will be rare as EID's due to constraints imposed by host specialization at each life-cycle stage. In contrast to predictions of this theory, we report 2 new intermediate hosts in the 3-host life cycle of the liver fluke Dicrocoelium dendriticum in Cypress Hills Provincial Park, Alberta, Canada. Results of sequence analysis of the cytochrome oxidase 1 (cox1) mitochondrial gene identified the terrestrial snail Oreohelix subrudis, and the ant, Formica aserva, as first and second intermediate hosts, respectively, in the region. Neither of these intermediate hosts, nor their suite of domestic and wild mammalian grazers used in the life cycle, occurs within the native range of D. dendriticum in Europe. Our results from host surveys show that the prevalence of D. dendriticum in samples of O. subrudis varied between 4-10%, whereas mean metacercariae intensity in F. aserva varied between 33-41 (n = 163, mean ± SD = 38 ± 35). These results are the first to describe the complete life cycle of emerging lancet fluke in western North America. The process of multi-level ecological fitting, in which the lancet fluke possesses pre-existing traits to utilize host resources, rather than host species, at each life-cycle stage provides a mechanism for the establishment of this complex life cycle in a novel habitat and in novel hosts.

  7. Fine-scale mapping of vector habitats using very high resolution satellite imagery: a liver fluke case-study.

    PubMed

    De Roeck, Els; Van Coillie, Frieke; De Wulf, Robert; Soenen, Karen; Charlier, Johannes; Vercruysse, Jozef; Hantson, Wouter; Ducheyne, Els; Hendrickx, Guy

    2014-12-01

    The visualization of vector occurrence in space and time is an important aspect of studying vector-borne diseases. Detailed maps of possible vector habitats provide valuable information for the prediction of infection risk zones but are currently lacking for most parts of the world. Nonetheless, monitoring vector habitats from the finest scales up to farm level is of key importance to refine currently existing broad-scale infection risk models. Using Fasciola hepatica, a parasite liver fluke, as a case in point, this study illustrates the potential of very high resolution (VHR) optical satellite imagery to efficiently and semi-automatically detect detailed vector habitats. A WorldView2 satellite image capable of <5m resolution was acquired in the spring of 2013 for the area around Bruges, Belgium, a region where dairy farms suffer from liver fluke infections transmitted by freshwater snails. The vector thrives in small water bodies (SWBs), such as ponds, ditches and other humid areas consisting of open water, aquatic vegetation and/or inundated grass. These water bodies can be as small as a few m2 and are most often not present on existing land cover maps because of their small size. We present a classification procedure based on object-based image analysis (OBIA) that proved valuable to detect SWBs at a fine scale in an operational and semi-automated way. The classification results were compared to field and other reference data such as existing broad-scale maps and expert knowledge. Overall, the SWB detection accuracy reached up to 87%. The resulting fine-scale SWB map can be used as input for spatial distribution modelling of the liver fluke snail vector to enable development of improved infection risk mapping and management advice adapted to specific, local farm situations.

  8. Mitochondrial and nuclear ribosomal DNA dataset supports that Paramphistomum leydeni (Trematoda: Digenea) is a distinct rumen fluke species.

    PubMed

    Ma, Jun; He, Jun-Jun; Liu, Guo-Hua; Zhou, Dong-Hui; Liu, Jian-Zhi; Liu, Yi; Zhu, Xing-Quan

    2015-04-02

    Rumen flukes parasitize the rumen and reticulum of ruminants, causing paramphistomiasis. Over the years, there has been considerable debate as to whether Paramphistomum leydeni and Paramphistomum cervi are the same or distant species. In the present study, the complete mitochondrial (mt) genome of P. leydeni was amplified using PCR-based sequencing and compared with that of P. cervi. The second internal transcribed spacer (ITS-2) of nuclear ribosomal DNA (rDNA) of P. leydeni specimens (n = 6) and P. cervi specimens (n = 8) was amplified and then sequenced. Phylogenetic relationship of the concatenated amino acid sequence data for 12 protein-coding genes of the two rumen flukes and selected members of Trematoda was evaluated using Bayesian inference (BI). The complete mt genome of P. leydeni was 14,050 bp in size. Significant nucleotide difference between the P. leydeni mt genome and that of P. cervi (14.7%) was observed. For genetic divergence in ITS-2, sequence difference between P. leydeni and P. cervi was 3.1%, while no sequence variation was detected within each of them. Phylogenetic analysis indicated that P. leydeni and P. cervi are closely-related but distinct rumen flukes. Results of the present study support the proposal that P. leydeni and P. cervi represent two distinct valid species. The mt genome sequences of P. leydeni provide plentiful resources of mitochondrial markers, which can be combined with nuclear markers, for further comparative studies of the biology of P. leydeni and its congeners from China and other countries.

  9. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia.

    PubMed

    Sissay, Menkir M; Uggla, Arvid; Waller, Peter J

    2007-10-01

    A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger Oesopha-gostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the

  10. Dark matters: exploitation as cooperation.

    PubMed

    Dasgupta, Partha

    2012-04-21

    The empirical literature on human cooperation contains studies of communitarian institutions that govern the provision of public goods and management of common property resources in poor countries. Scholars studying those institutions have frequently used the Prisoners' Dilemma game as their theoretical tool-kit. But neither the provision of local public goods nor the management of local common property resources involves the Prisoners' Dilemma. That has implications for our reading of communitarian institutions. By applying a fundamental result in the theory of repeated games to a model of local common property resources, it is shown that communitarian institutions can harbour exploitation of fellow members, something that would not be possible in societies where cooperation amounts to overcoming the Prisoners' Dilemma. The conclusion we should draw is that exploitation can masquerade as cooperation.

  11. Teotihuacan, tepeapulco, and obsidian exploitation.

    PubMed

    Charlton, T H

    1978-06-16

    Current cultural ecological models of the development of civilization in central Mexico emphasize the role of subsistence production techniques and organization. The recent use of established and productive archeological surface survey techniques along natural corridors of communication between favorable niches for cultural development within the Central Mexican symbiotic region resulted in the location of sites that indicate an early development of a decentralized resource exploitation, manufacturing, and exchange network. The association of the development of this system with Teotihuacán indicates the importance such nonsubsistence production and exchange had in the evolution of this first central Mexican civilization. The later expansion of Teotihuacán into more distant areas of Mesoamerica was based on this resource exploitation model. Later civilizations centered at Tula and Tenochtitlán also used such a model in their expansion.

  12. Combining Slaughterhouse Surveillance Data with Cattle Tracing Scheme and Environmental Data to Quantify Environmental Risk Factors for Liver Fluke in Cattle.

    PubMed

    Innocent, Giles T; Gilbert, Lucy; Jones, Edward O; McLeod, James E; Gunn, George; McKendrick, Iain J; Albon, Steve D

    2017-01-01

    Liver fluke infection causes serious disease (fasciolosis) in cattle and sheep in many regions of the world, resulting in production losses and additional economic consequences due to condemnation of the liver at slaughter. Liver fluke depends on mud snails as an intermediate host and infect livestock when ingested through grazing. Therefore, environmental factors play important roles in infection risk and climate change is likely to modify this. Here, we demonstrate how slaughterhouse data can be integrated with other data, including animal movement and climate variables to identify environmental risk factors for liver fluke in cattle in Scotland. We fitted a generalized linear mixed model to the data, with exposure-weighted random and fixed effects, an approach which takes into account the amount of time cattle spent at different locations, exposed to different levels of risk. This enabled us to identify an increased risk of liver fluke with increased animal age, rainfall, and temperature and for farms located further to the West, in excess of the risk associated with a warmer, wetter climate. This model explained 45% of the variability in liver fluke between farms, suggesting that the unexplained 55% was due to factors not included in the model, such as differences in on-farm management and presence of wet habitats. This approach demonstrates the value of statistically integrating routinely recorded slaughterhouse data with other pre-existing data, creating a powerful approach to quantify disease risks in production animals. Furthermore, this approach can be used to better quantify the impact of projected climate change on liver fluke risk for future studies.

  13. Combining Slaughterhouse Surveillance Data with Cattle Tracing Scheme and Environmental Data to Quantify Environmental Risk Factors for Liver Fluke in Cattle

    PubMed Central

    Innocent, Giles T.; Gilbert, Lucy; Jones, Edward O.; McLeod, James E.; Gunn, George; McKendrick, Iain J.; Albon, Steve D.

    2017-01-01

    Liver fluke infection causes serious disease (fasciolosis) in cattle and sheep in many regions of the world, resulting in production losses and additional economic consequences due to condemnation of the liver at slaughter. Liver fluke depends on mud snails as an intermediate host and infect livestock when ingested through grazing. Therefore, environmental factors play important roles in infection risk and climate change is likely to modify this. Here, we demonstrate how slaughterhouse data can be integrated with other data, including animal movement and climate variables to identify environmental risk factors for liver fluke in cattle in Scotland. We fitted a generalized linear mixed model to the data, with exposure-weighted random and fixed effects, an approach which takes into account the amount of time cattle spent at different locations, exposed to different levels of risk. This enabled us to identify an increased risk of liver fluke with increased animal age, rainfall, and temperature and for farms located further to the West, in excess of the risk associated with a warmer, wetter climate. This model explained 45% of the variability in liver fluke between farms, suggesting that the unexplained 55% was due to factors not included in the model, such as differences in on-farm management and presence of wet habitats. This approach demonstrates the value of statistically integrating routinely recorded slaughterhouse data with other pre-existing data, creating a powerful approach to quantify disease risks in production animals. Furthermore, this approach can be used to better quantify the impact of projected climate change on liver fluke risk for future studies. PMID:28534030

  14. The effect of lysergic acid diethylamide, 5-hydroxytryptamine, and related compounds on the liver fluke, fasciola hepatica

    PubMed Central

    Mansour, T. E.

    1957-01-01

    The rhythmical activity of the liver fluke, Fasciola hepatica, was stimulated by 5-hydroxytryptamine and by lysergic acid diethylamide at very low concentrations. The effect was peripheral and was not mediated through the central ganglion. Other amines also stimulated rhythmical activity, the most potent being the indolamines. Bromolysergic acid diethylamide, and other analogues such as yohimbine, harmine, and dopamine depressed rhythmical movement and antagonized the stimulant action of 5-hydroxytryptamine and lysergic acid diethylamide. Evidence which suggests the presence of tryptamine receptors in the trematode is discussed. PMID:13489165

  15. The effects of farm management practices on liver fluke prevalence and the current internal parasite control measures employed on Irish dairy farms.

    PubMed

    Selemetas, Nikolaos; Phelan, Paul; O'Kiely, Padraig; de Waal, Theo

    2015-01-30

    Fasciolosis caused by Fasciola hepatica is responsible for major production losses in cattle farms. The objectives of this study were to assess the effect of farm management practices on liver fluke prevalence on Irish dairy farms and to document the current control measures against parasitic diseases. In total, 369 dairy farms throughout Ireland were sampled from October to December 2013, each providing a single bulk tank milk (BTM) sample for liver fluke antibody-detection ELISA testing and completing a questionnaire on their farm management. The analysis of samples showed that cows on 78% (n=288) of dairy farms had been exposed to liver fluke. There was a difference (P<0.05) between farms where cows were positive or negative for liver fluke antibodies in (a) the total number of adult dairy cows in herds, (b) the number of adult dairy cows contributing to BTM samples, and (c) the size of the total area of grassland, with positive farms having larger numbers in each case. There was no difference (P>0.05) between positive and negative farms in (a) the grazing of dry cows together with replacement cows, (b) whether or not grazed grassland was mowed for conservation, (c) the type of drinking water provision system, (d) spreading of cattle manure on grassland or (e) for grazing season length (GSL; mean=262.5 days). Also, there were differences (P<0.001) between drainage statuses for GSL with farms on good drainage having longer GSL than moderately drained farms. The GSL for dairy cows on farms with good drainage was 11 days longer than for those with moderate drainage (P<0.001). The percentage of farmers that used an active ingredient during the non-lactating period against liver fluke, gastrointestinal nematodes, lungworm, and rumen fluke was 96%, 85%, 77% and 90%, respectively. Albendazole was the most frequently used active ingredient for treatment against gastrointestinal nematodes (57%), liver fluke (40%) and lungworm (47%), respectively. There was a difference

  16. Mitochondrial DNA haplotype analysis of liver fluke in bison from Bialowieza Primaeval Forest indicates domestic cattle as the likely source of infection.

    PubMed

    Walker, Stephen M; Demiaszkiewicz, Aleksander W; Kozak, Monika; Wedrychowicz, Halina; Teofanova, Denitsa; Prodohl, Paulo; Brennan, Gerry; Fairweather, Ian; Hoey, Elizabeth M; Trudgett, Alan

    2013-01-16

    We have determined the mitochondrial genotype of liver fluke present in Bison (Bison bonasus) from the herd maintained in the Bialowieza National Park in order to determine the origin of the infection. Our results demonstrated that the infrapopulations present in the bison were genetically diverse and were likely to have been derived from the population present in local cattle. From a consideration of the genetic structure of the liver fluke infrapopulations we conclude that the provision of hay at feeding stations may be implicated in the transmission of this parasite to the bison. This information may be of relevance to the successful management of the herd.

  17. Routing Algorithm Exploits Spatial Relations

    NASA Technical Reports Server (NTRS)

    Okino, Clayton; Jennings, Esther

    2004-01-01

    A recently developed routing algorithm for broadcasting in an ad hoc wireless communication network takes account of, and exploits, the spatial relationships among the locations of nodes, in addition to transmission power levels and distances between the nodes. In contrast, most prior algorithms for discovering routes through ad hoc networks rely heavily on transmission power levels and utilize limited graph-topology techniques that do not involve consideration of the aforesaid spatial relationships. The present algorithm extracts the relevant spatial-relationship information by use of a construct denoted the relative-neighborhood graph (RNG).

  18. Molecular Changes in Opisthorchis viverrini (Southeast Asian Liver Fluke) during the Transition from the Juvenile to the Adult Stage

    PubMed Central

    Sripa, Jittiyawadee; Hall, Ross S.; Scheerlinck, Jean-Pierre; Laha, Thewarach; Sripa, Banchob; Gasser, Robin B.

    2012-01-01

    Background The Southeast Asian liver fluke (Opisthorchis viverrini) chronically infects and affects tens of millions of people in regions of Asia, leading to chronic illness and, importantly, inducing malignant cancer ( = cholangiocarcinoma). In spite of this, little is known, at the molecular level, about the parasite itself, its interplay with its hosts or the mechanisms of disease and/or carcinogenesis. Methodology/Principal Findings Here, we generated extensive RNA-Seq data (Illumina) representing adult and juvenile stages of O. viverrini, and combined these sequences with previously published transcriptomic data (454 technology) for this species, yielding a combined assembly of significantly increased quality and allowing quantitative assessment of transcription in the juvenile and adult stage. Conclusions This enhanced assembly reveals that, despite the substantial biological similarities between the human liver flukes, O. viverinni and Clonorchis sinensis, there are previously unrecognized differences in major aspects of their molecular biology. Most notable are differences among the C13 and cathepsin L-like cysteine peptidases, which play key roles in tissue migration, immune evasion and feeding, and, thus, represent potential drug and/or vaccine targets. Furthermore, these data indicate that major lineages of cysteine peptidases of socioeconomically important trematodes have evolved through a process of gene loss rather than independent radiation, contrasting previous proposals. PMID:23209858

  19. Suppression of trophoblast cell surface antigen 2 enhances proliferation and migration in liver fluke-associated cholangiocarcinoma.

    PubMed

    Sawanyawisuth, Kanlayanee; Tantapotinan, Nattawat; Wongkham, Chaisiri; Riggins, Gregory J; Kraiklang, Ratthaphol; Wongkham, Sopit; Puapairoj, Anucha

    2016-01-01

    Trophoblast cell surface antigen 2 (TROP2) or tumor-associated calcium signal transducer 2 (TACSTD2) is a 36-kDa type I transmembrane glycoprotein and exerts dual functions as an oncogene and tumor suppressor in cancer cells. In this study, we investigated the expression and functions of TROP2 in liver fluke-associated cholangiocarcinoma (CCA). TROP2 expression in 85 CCA tissues was detected by using immunohistochemistry. The methylation status of TROP2 promoter was studied in 15 matched pairs of normal and CCA formalin fixed paraffin embedded (FFPE) tissues using the bisulfite genomic sequencing (BGS) method. The functions of TROP2 on cancer cell behavior were investigated using siRNA in CCA cell lines. Proliferation, migration and invasion assays were performed. A PCR array was used to evaluate the impact of TROP2 knockdown on the gene expression profiles. TROP2 was highly expressed in all normal bile duct epithelia, but significantly down-regulated in CCA cells. Sixty percent of CCA revealed promoter hypermethylation compared to the corresponding adjacent normal tissues. TROP2 knockdown significantly enhanced the proliferation and migration in CCA cell lines, and altered the expressions of MARCK, EMP1 and FILIP1L. We provide new evidence that TROP2 is epigenetically down-regulated and operates as a negative regulator of cell proliferation and migration in liver fluke-associated CCA.

  20. Comparative morphology of eggs of the Haplorchiinae (Trematoda: Heterophyidae) and some other medically important heterophyid and opisthorchiid flukes.

    PubMed

    Ditrich, O; Giboda, M; Scholz, T; Beer, S A

    1992-01-01

    The egg morphology of the following medically important small flukes from Southeast Asia and Far East were studied: Opisthorchis viverrini, Clonorchis sinensis (Opisthorchiidae), Haplorchis taichui, H. pumilio, H. yokogawai, Stellantchasmus falcatus and Metagonimus sp. (Heterophydiae). This study revealed a great intraspecific variability and interspecific similarity in size and shape of eggs. The eggs shape does not seem to be suitable for species identification. On the other hand, biometrical analysis of egg size enabled us to divide eggs from the species studied into four distinct groups according to the Faust-Meleney index (FMI) characterizing egg size rather than the length and width of eggs. The surface structures of eggs, delineated by using a scanning electron microscope (SEM), appeared to be a suitable morphological feature for distinguishing some groups of small flukes. Eggs from the Haplorchiinae were typified by the characteristic filamentous mesh structure. The problems of identification of eggs in human stool samples and suitability of using morphological criteria such as shape and size of eggs are discussed herein.

  1. Low Genetic Diversity in Wide-Spread Eurasian Liver Fluke Opisthorchis felineus Suggests Special Demographic History of This Trematode Species

    PubMed Central

    Brusentsov, Ilja I.; Katokhin, Alexey V.; Brusentsova, Irina V.; Shekhovtsov, Sergei V.; Borovikov, Sergei N.; Goncharenko, Grigoriy G.; Lider, Lyudmila A.; Romashov, Boris V.; Rusinek, Olga T.; Shibitov, Samat K.; Suleymanov, Marat M.; Yevtushenko, Andrey V.; Mordvinov, Viatcheslav A.

    2013-01-01

    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. PMID:23634228

  2. The first comprehensive study of praziquantel effects in vivo and in vitro on European liver fluke Opisthorchis felineus (Trematoda).

    PubMed

    Pakharukova, Mariya Y; Shilov, Alexander G; Pirozhkova, Darya S; Katokhin, Alexey V; Mordvinov, Viatcheslav A

    2015-07-01

    The European liver fluke Opisthorchis felineus (Rivolta, 1884) is an epidemiologically important parasite infecting mammals, including humans. Opisthorchis felineus is widespread in Russia, Kazakhstan and Eastern European countries. Praziquantel (PZQ) is the drug of choice for the treatment of opisthorchiasis, but the effects of this drug on O. felineus are poorly studied. The aims of this work were (i) to perform a study of PZQ effects in vitro, (ii) to identify morphological markers of PZQ action on O. felineus, (iii) to analyse damage to the worm surface and (iv) to assess the efficacy of PZQ in vivo in a hamster model. Light microscopy, optical sectioning and fluorescence microscopy were used to study morphological changes. In vivo, PZQ at a dose of 400mg/kg reduced the rate of infection in experimental acute and chronic opisthorchiasis in hamsters by 70% and 79%, respectively. In vitro, the drug caused destruction and vacuolisation of the tegument of O. felineus, contractions of the worm musculature, paralysis, and irreversible changes in morphology (IC50=0.14μg/mL). Differences in susceptibility to the drug between adult and newly excysted metacercariae were also observed. Qualitative effects of PZQ in vivo and in vitro were similar to the drug's effects on other trematodes, including epidemiologically important liver flukes. Nevertheless, high heterogeneity of O. felineus specimens in terms of susceptibility to the drug was observed. In addition, we describe for the first time the high rate of recovery of O. felineus following the destructive action of PZQ.

  3. Two species of goby, Boleophthalmus pectinirostris and Scartelaos sp., as the new second intermediate hosts of heterophyid fluke in Korea

    PubMed Central

    Kim, Jung-A; Song, Hyun-Jae

    2005-01-01

    A survey was performed in order to determine the infection status of the metacercariae of heterophyid fluke in two goby species, Boleophthalmus pectinirostris and Scartelaos sp., collected from Gangjin-gun, and Shinan-gun, Sooncheon-shi, Jeollanam-do, Republic of Korea. A total of three metacercariae of Heterophyopsis continua was found in only one B. pectinirostris (10.0%) from Gangjin-gun. Heterophyes nocens metacercariae were detected in 24 B. pectinirostris (96.0%) and 14 Scartelaos sp. (63.6%) from Shinan-gun. Heterophyopsis continua metacercariae were found in 11 B. pectinirostris (44.0%) and 21 Scartelaos sp. (95.5%) from Shinan-gun. Stictodora fuscata metacercariae were detected in 18 B. pectinirostris (72.0%) from Shinan-gun. No metacercariae were detected in 20 B. pectinirostris from Sooncheon-shi. From the above results, this study is the first to prove that B. pectinirostris and Scartelaos sp. serve as the second intermediate hosts of some heterophyid flukes in Korea. PMID:16340306

  4. Liver fluke (Fasciola hepatica) naturally infecting introduced European brown hare (Lepus europaeus) in northern Patagonia: phenotype, prevalence and potential risk.

    PubMed

    Cuervo, Pablo F; Cataldo, Sophia Di; Fantozzi, M Cecilia; Deis, Erika; Isenrath, Gabriela Diaz; Viberti, Gabriela; Artigas, Patricio; Peixoto, Raquel; Valero, M Adela; Sierra, Roberto Mera Y; Mas-Coma, Santiago

    2015-09-01

    Fascioliasis has recently been included in the WHO list of Neglected Zoonotic Diseases. Besides being a major veterinary health problem, fascioliasis has large underdeveloping effects on the human communities affected. Though scarcely considered in fascioliasis epidemiology, it is well recognized that both native and introduced wildlife species may play a significant role as reservoirs of the disease. The objectives are to study the morphological characteristics of Fasciola hepatica adults and eggs in a population of Lepus europaeus, to assess liver fluke prevalence, and to analyze the potential reservoir role of the European brown hare in northern Patagonia, Argentina, where fascioliasis is endemic. Measures of F. hepatica found in L. europaeus from northern Patagonia demonstrate that the liver fluke is able to fully develop in wild hares and to shed normal eggs through their faeces. Egg shedding to the environment is close to the lower limit obtained for pigs, a domestic animal whose epidemiological importance in endemic areas has already been highlighted. The former, combined with the high prevalence found (14.28%), suggest an even more important role in the transmission cycle than previously considered. The results obtained do not only remark the extraordinary plasticity and adaptability of this trematode species to different host species, but also highlight the role of the European brown hare, and other NIS, as reservoirs capable for parasite spillback to domestic and native cycle, representing a potentially important, but hitherto neglected, cause of disease emergence.

  5. Prevalence of Platynosomum fastosum infection in free roaming cats in northeastern Brazil: Fluke burden and grading of lesions.

    PubMed

    Braga, R R; Teixeira, A C; Oliveira, J A A; Cavalcanti, L P G

    The objective of this paper was to investigate prevalence and parasite load of the trematode Platynosomum fastosum infection and the risk of developing cholangitis/cholangiohepatitis among infected domestic cats in a city of northeastern Brazil, and to characterize the influence of fluke burden in the formation of lesions in liver and gallbladder. A total of 141 cats was necropsied and examined for the presence of P. fastosum. The observed prevalence was 42.6% (60/141, 95% CI=34.2-50.9). Parasite load varied from 1 to 219 flukes per animal. Adult cats were more frequently infected than kittens (p<0.01). Risk of cholangitis was about three times higher in infected animals (RR=3.23, 95% CI=2.01-5.07, p<0.01). Centrolobular congestion, portal cholangitis and cholestasis was significantly more common in infected as compared to non-infected cats (p<0.01). Similarly, fibrosis, cholangitis and mucous gland hyperplasia were significantly more prevalent in the bile duct of infected animals (p<0.01). Mild fibrosis and cholecystitis were observed principally in infected cats. Hyperplastic precursor lesions of cholangiocarcinoma were observed, but no solid tumor was diagnosed. These results reveal high prevalence of P. fastosum in free roaming cats in northeastern Brazil, with increased risk of liver disease.

  6. Identification and characterization of microRNAs in the pancreatic fluke Eurytrema pancreaticum

    PubMed Central

    2013-01-01

    Background Eurytrema pancreaticum is one of the most common flukes, which mainly infects ruminants globally and infects human beings accidentally; causing eurytremiasis that has high veterinary and economic importance. MicroRNAs (miRNAs) are small non-coding RNAs and are now considered as a key mechanism of gene regulation at the post-transcription level. Methods We investigated the global miRNA expression profile of E. pancreaticum adults using next-generation sequencing technology combined with real-time quantitative PCR. Results By using the genome of the closely-related species Schistosoma japonicum as reference, we obtained 27 miRNA candidates out of 16.45 million raw sequencing reads, with 13 of them found as known miRNAs in S. japonicum and/or S. mansoni, and the remaining 14 miRNAs were considered as novel. Five out of the 13 known miRNAs coming from one family named as sja-miR-2, including family members from miR-2a to miR-2e. Targets of 19 miRNAs were successfully predicated out of the 17401 mRNA and EST non-redundant sequences of S. japonicum. It was found that a significant high number of targets were related to “chch domain-containing protein mitochondrial precursor” (n = 29), “small subunit ribosomal protein s30e” (n = 21), and “insulin-induced gene 1 protein” (n = 9). Besides, “egg protein cp3842” (n = 2), “fumarate hydratase” (n = 2), “ubiquitin-conjugating enzyme” (n = 2), and “sperm-associated antigen 6” (n = 1) were also found as targets of the miRNAs of E. pancreaticum. Conclusions The present study represents the first global characterization of E. pancreaticum miRNAs, which provides novel resources for a better understanding of the parasite, which, in turn, has implications for the effective control of the disease it causes. PMID:23351883

  7. Survey of transcripts expressed by the invasive juvenile stage of the liver fluke Fasciola hepatica

    PubMed Central

    2010-01-01

    Background The common liver fluke Fasciola hepatica is the agent of a zoonosis with significant economic consequences in livestock production worldwide, and increasing relevance to human health in developing countries. Although flukicidal drugs are available, re-infection and emerging resistance are demanding new efficient and inexpensive control strategies. Understanding the molecular mechanisms underlying the host-parasite interaction provide relevant clues in this search, while enlightening the physiological adaptations to parasitism. Genomics and transcriptomics are still in their infancy in F. hepatica, with very scarce information available from the invasive newly excysted juveniles (NEJ). Here we provide an initial glimpse to the transcriptomics of the NEJ, the first stage to interact with the mammalian host. Results We catalogued more than 500 clusters generated from the analysis of F. hepatica juvenile expressed sequence tags (EST), several of them not detected in the adult stage. A set of putative F. hepatica specific transcripts, and a group of sequences conserved exclusively in flatworms were identified. These novel sequences along with a set of parasite transcripts absent in the host genomes are putative new targets for future anti-parasitic drugs or vaccine development. Comparisons of the F. hepatica sequences with other metazoans genomes or EST databases were consistent with the basal positioning of flatworms in the bilaterian phylogeny. Notably, GC content, codon usage and amino acid frequencies are remarkably different in Schistosomes to F. hepatica and other trematodes. Functional annotation of predicted proteins showed a general representation of diverse biological functions. Besides proteases and antioxidant enzymes expected to participate in the early interaction with the host, various proteins involved in gene expression, protein synthesis, cell signaling and mitochondrial enzymes were identified. Differential expression of secreted protease

  8. Comparative histopathology of Opisthorchis felineus and Opisthorchis viverrini in a hamster model: an implication of high pathogenicity of the European liver fluke.

    PubMed

    Lvova, Maria N; Tangkawattana, Sirikachorn; Balthaisong, Suwit; Katokhin, Alexey V; Mordvinov, Viatcheslav A; Sripa, Banchob

    2012-03-01

    European liver fluke (Opisthorchis felineus) and Asian liver fluke (Opisthorchis viverrini) are similar in morphology but comparative pathology of the infections has not been described. We therefore did comparative histopathology of both parasites in an experimental animal model. The study was conducted in 3 groups of 105 Syrian golden hamsters; the first and second groups fed with 50 metacercariae of O. felineus (OF) or O. viverrini (OV) and the last group was uninfected controls. Five hamsters in each group were euthanized on weeks 1, 2, 4, 8, 12 and 24 post-infection. The liver tissue was fixed and processed for routine histopathology and immunohistochemistry for proliferation markers (BrdU or PCNA). Overall, the liver histopathology of O. felineus and O. viverrini infection was generally similar. However, various histopathogical features including intense inflammation, fibrosis, biliary and goblet cell hyperplasia and dysplasia occurred earlier in the OF group. In addition, the existence of precancerous lesions such as cholangiofibrosis in a long-term infection was observed only in this group. O. felineus is larger in size than O. viverrini which, together with its excreted and secreted antigens, likely is crucial in the induction of liver fluke induced disease. The differences in nature and timing of the histopathological profile indicate that opisthorchiasis caused by the European liver fluke O. felineus is more pathogenic than its Asian relative O. viverrini. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  9. TAXONOMICAL AND ECOLOGICAL STUDIES ON THE LUNG FLUKE, PARAGONIMUS IN THE PACIFIC AREA, WITH SPECIAL REFERENCE TO SOUTH-EAST ASIA.

    DTIC Science & Technology

    brown rat, Rattus norvegicus and the wild boar, Sus scrofa leucomystax were revealed to be the final host of P. miyazakii. (3) P. sadoensis was found...8) In Mexico , two species of Paragonimus were recognized, and one was most probably a new species and the other was similar to the new fluke found in Colombia. (Author)

  10. The effectiveness of repeated tank treatments of copper sulfate and formalin on gill flukes and Ich in naturally infested white bass

    USDA-ARS?s Scientific Manuscript database

    Ectoparasites infesting the gills of juvenile fish reared in tanks can cause serious fish losses. Multiple treatments of formalin and copper sulfate (CuSO4) were evaluated for effectiveness against a natural infestation of gill flukes Onchocleidus mimus (Monogenoidea: Ancyrocephalidae) and Ichthyop...

  11. Exploiting social evolution in biofilms.

    PubMed

    Boyle, Kerry E; Heilmann, Silja; van Ditmarsch, Dave; Xavier, Joao B

    2013-04-01

    Bacteria are highly social organisms that communicate via signaling molecules, move collectively over surfaces and make biofilm communities. Nonetheless, our main line of defense against pathogenic bacteria consists of antibiotics-drugs that target individual-level traits of bacterial cells and thus, regrettably, select for resistance against their own action. A possible solution lies in targeting the mechanisms by which bacteria interact with each other within biofilms. The emerging field of microbial social evolution combines molecular microbiology with evolutionary theory to dissect the molecular mechanisms and the evolutionary pressures underpinning bacterial sociality. This exciting new research can ultimately lead to new therapies against biofilm infections that exploit evolutionary cheating or the trade-off between biofilm formation and dispersal.

  12. Energy for lunar resource exploitation

    NASA Astrophysics Data System (ADS)

    Glaser, Peter E.

    1992-02-01

    Humanity stands at the threshold of exploiting the known lunar resources that have opened up with the access to space. America's role in the future exploitation of space, and specifically of lunar resources, may well determine the level of achievement in technology development and global economic competition. Space activities during the coming decades will significantly influence the events on Earth. The 'shifting of history's tectonic plates' is a process that will be hastened by the increasingly insistent demands for higher living standards of the exponentially growing global population. Key to the achievement of a peaceful world in the 21st century, will be the development of a mix of energy resources at a societally acceptable and affordable cost within a realistic planning horizon. This must be the theme for the globally applicable energy sources that are compatible with the Earth's ecology. It is in this context that lunar resources development should be a primary goal for science missions to the Moon, and for establishing an expanding human presence. The economic viability and commercial business potential of mining, extracting, manufacturing, and transporting lunar resource based materials to Earth, Earth orbits, and to undertake macroengineering projects on the Moon remains to be demonstrated. These extensive activities will be supportive of the realization of the potential of space energy sources for use on Earth. These may include generating electricity for use on Earth based on beaming power from Earth orbits and from the Moon to the Earth, and for the production of helium 3 as a fuel for advanced fusion reactors.

  13. Energy for lunar resource exploitation

    NASA Technical Reports Server (NTRS)

    Glaser, Peter E.

    1992-01-01

    Humanity stands at the threshold of exploiting the known lunar resources that have opened up with the access to space. America's role in the future exploitation of space, and specifically of lunar resources, may well determine the level of achievement in technology development and global economic competition. Space activities during the coming decades will significantly influence the events on Earth. The 'shifting of history's tectonic plates' is a process that will be hastened by the increasingly insistent demands for higher living standards of the exponentially growing global population. Key to the achievement of a peaceful world in the 21st century, will be the development of a mix of energy resources at a societally acceptable and affordable cost within a realistic planning horizon. This must be the theme for the globally applicable energy sources that are compatible with the Earth's ecology. It is in this context that lunar resources development should be a primary goal for science missions to the Moon, and for establishing an expanding human presence. The economic viability and commercial business potential of mining, extracting, manufacturing, and transporting lunar resource based materials to Earth, Earth orbits, and to undertake macroengineering projects on the Moon remains to be demonstrated. These extensive activities will be supportive of the realization of the potential of space energy sources for use on Earth. These may include generating electricity for use on Earth based on beaming power from Earth orbits and from the Moon to the Earth, and for the production of helium 3 as a fuel for advanced fusion reactors.

  14. Development of a Health Education Modification Program Regarding Liver Flukes and Cholangiocarcinoma in High Risk Areas of Nakhon Ratchasima Province Using Self-Efficacy and Motivation Theory.

    PubMed

    Kaewpitoon, Soraya J; Rujirakul, Ratana; Wakkuwattapong, Parichart; Benjaoran, Fuangfa; Norkaew, Jun; Kujapun, Jirawoot; Ponphimai, Sukanya; Chavenkun, Wasugree; Kompor, Porntip; Padchasuwan, Natnapa; Kaewpitoon, Natthawut

    2016-01-01

    A quasi-experimental study was conducted to develop a health education modification program based on self-efficacy and motivation regarding liver flukes and cholangiocarcinoma development in Keang Sanam Nang district, Nakhon Ratchasima province, Thailand. A total of 36 individuals were invited to participate in the program and were screened for population at risk of liver fluke infection and cholangiocarcinoma using SUT-OV-001 and SUT-CCA-001. Development of health education modification program regarding liver fluke and cholangiocarcinoma prevention included 3 steps: (1) preparation, (2) health education program, and (3) follow-up and evaluation. The study was implemented for 10 weeks. Pre-and-post-test knowledge was measured with questionnaires, Kuder-Richardson-20: KR-20 = 0.718,and Cronbach's Alpha Coefficient = 0.724 and 0.716 for perception and outcome expectation questionnaires. Paired and independent t-tests were applied for data analysis. The majority of the participants were female (55.6%), aged between ≤50 and 60 years old (36.1%), married (86.1%), education level of primary school (63.9%), agricultural occupation (80.6%), and income <4,000 Baht (44.4%). The results revealed that after the health education program, the experimental group had a mean score of knowledge, perception, and outcome expectation regarding liver fluke and cholangiocarcinoma prevention significantly higher than before participation and in the control group. In conclusion, this successful health education modification program for liver fluke and cholangiocarcinoma, therefore may useful for further work behavior modification in other epidemic areas.

  15. Opportunistic exploitation: an overlooked pathway to extinction.

    PubMed

    Branch, Trevor A; Lobo, Aaron S; Purcell, Steven W

    2013-07-01

    How can species be exploited economically to extinction? Past single-species hypotheses examining the economic plausibility of exploiting rare species have argued that the escalating value of rarity allows extinction to be profitable. We describe an alternative pathway toward extinction in multispecies exploitation systems, termed 'opportunistic exploitation'. In this mode, highly valued species that are targeted first by fishing, hunting, and logging become rare, but their populations can decline further through opportunistic exploitation while more common but less desirable species are targeted. Effectively, expanding exploitation to more species subsidizes the eventual extinction of valuable species at low densities. Managers need to recognize conditions that permit opportunistic depletion and pass regulations to protect highly desirable species when exploitation can expand to other species.

  16. Molecular Characterization of the North American Lung Fluke Paragonimus kellicotti in Missouri and its Development in Mongolian Gerbils

    PubMed Central

    Fischer, Peter U.; Curtis, Kurt C.; Marcos, Luis A.; Weil, Gary J.

    2011-01-01

    Human paragonimiasis is an emerging disease in Missouri. To characterize local parasites, we examined crayfish from three rivers. Metacercaeriae consistent with Paragonimus kellicotti were detected in 69%, 67%, and 37% of crayfish from the Big Piney, Huzzah, and Black Rivers, respectively. Sequencing of the second internal transcribed spacer and other DNA markers confirmed the species identification and the presence of identical parasite sequences in clinical specimens from two human cases. Mongolian gerbils were infected by intraperitoneal injection with 3–8 metacercariae. Most gerbils died 15–49 days post-infection. Necropsies showed pulmonary hemorrhage with necrosis, and flukes as long as 8 mm were recovered from intrathoracic tissues. Western blot analysis using P. kellicotti antigen showed a strong antibody response in gerbils 39 days post-infection. These results demonstrate that P. kellicotti is common in Missouri crayfish. The gerbil model may be useful for research on the pathogenesis, immunology, and treatment of paragonimiasis. PMID:21633042

  17. Molecular characterization of the North American lung fluke Paragonimus kellicotti in Missouri and its development in Mongolian gerbils.

    PubMed

    Fischer, Peter U; Curtis, Kurt C; Marcos, Luis A; Weil, Gary J

    2011-06-01

    Human paragonimiasis is an emerging disease in Missouri. To characterize local parasites, we examined crayfish from three rivers. Metacercaeriae consistent with Paragonimus kellicotti were detected in 69%, 67%, and 37% of crayfish from the Big Piney, Huzzah, and Black Rivers, respectively. Sequencing of the second internal transcribed spacer and other DNA markers confirmed the species identification and the presence of identical parasite sequences in clinical specimens from two human cases. Mongolian gerbils were infected by intraperitoneal injection with 3-8 metacercariae. Most gerbils died 15-49 days post-infection. Necropsies showed pulmonary hemorrhage with necrosis, and flukes as long as 8 mm were recovered from intrathoracic tissues. Western blot analysis using P. kellicotti antigen showed a strong antibody response in gerbils 39 days post-infection. These results demonstrate that P. kellicotti is common in Missouri crayfish. The gerbil model may be useful for research on the pathogenesis, immunology, and treatment of paragonimiasis.

  18. Data set from the proteomic analysis of Bithynia siamensis goniomphalos snails upon infection with the carcinogenic liver fluke Opisthorchis viverrini

    PubMed Central

    Prasopdee, Sattrachai; Tesana, Smarn; Cantacessi, Cinzia; Laha, Thewarach; Mulvenna, Jason; Grams, Rudi; Loukas, Alex; Sotillo, Javier

    2014-01-01

    The snail Bithynia siamensis goniomphalos acts as the first intermediate host for the human liver fluke Opisthorchis viverrini, the major cause of cholangiocarcinoma (CCA) in Northeast Thailand. This data article contains the results obtained from the analysis of the proteins differentially expressed in the snail B. siamensis goniomphalos upon infection with O. viverrini. It contains the data generated from iQuantitator software including a pdf of each sample with a protein׳s relative expression summary and a per-protein detailed analysis of all time points studied and an excel file for each sample containing the raw data from iQuantitator analysis, including ID, mean, standard deviation, credible interval, log2 and description for every protein identified in each of the samples. PMID:26217698

  19. Austropeplea ollula (Pulmonata: Lymnaeidae): A new molluscan intermediate host of a human intestinal fluke, Echinostoma cinetorchis (Trematoda: Echinostomatidae) in Korea

    PubMed Central

    Jung, Younghun; Park, Yun-Kyu; Hwang, Myung-Ki

    2001-01-01

    Three freshwater snail species of the family Lymnaeidae have been reported from Korea, Radix auricularia coreana, Austropeplea ollula and Fossaria truncatula. Out of 3 lymnaeid snail species, A. ollula was naturally infected with the Echinostoma cinetorchis cercariae (infection rate = 0.7%). In the experiments with the laboratory-bred snails, F. truncatula as well as A. ollula was also susceptible to the E. cinetorchis miracidia with infection rates of 25% and 40%, respectively. All of three lymnaeid snail species exposed to the E. cinetorchis cercariae were infected with the E. cinetorchis metacercariae. It is evident that A. ollula acts as the first molluscan intermediate host of E. cinetorchis in Korea, and F. truncatula may be a possible candidate for the first intermediate host of this intestinal fluke. Also, three lymnaeid snail species targeted were experimentally infected with E. cinetorchis metacercariae. PMID:11590915

  20. The Gaia scientific exploitation networks

    NASA Astrophysics Data System (ADS)

    Figueras, F.; Jordi, C.

    2015-05-01

    On July 2014 the Gaia satellite, placed at L2 since January 2014, finished their commissioning phase and started collecting high accurate scientific data. New and more realistic estimations of the astrometric, photometric and spectroscopic accuracy expected after five years mission operation (2014-2019) have been recently published in the Gaia Science Performance Web page. Here we present the coordination efforts and the activities being conducted through the two GREAT (Gaia Research for European Astronomy Training) European Networks, the GREAT-ESF, a programme supported by the European Science Foundation (2010-2015), and the GREAT-ITN network, from the European Union's Seventh Framework Programme (2011-2015). The main research theme of these networks is to unravel the origin and history of our home galaxy. Emphasis is placed on the research projects being conducted by the Spanish Researchers through these networks, well coordinated by the Red Española de Explotación Científica de Gaia (REG network, with more than 140 participants). Members of the REG play an important role on the collection of complementary spectroscopic data from ground based telescopes, on the development of new tools for an optimal scientific exploitation of Gaia data and on the preparation task to create the Gaia archive.

  1. Exploiting dual otoacoustic emission sources

    NASA Astrophysics Data System (ADS)

    Abdala, Carolina; Kalluri, Radha

    2015-12-01

    Two distinct processes generate otoacoustic emissions (OAEs). Reflection-source emissions, here recorded as stimulus frequency OAEs, are optimally informative at low sound levels and are more sensitive to slight hearing loss; they have been linked to cochlear amplifier gain and tuning. Distortion-source emissions are strongest at moderate-high sound levels and persist despite mild hearing loss; they likely originate in the nonlinear process of hair cell transduction. In this preliminary study, we exploit the unique features of each by generating a combined reflection-distortion OAE profile in normal hearing and hearing-impaired ears. Distortion-product (DP) and stimulus-frequency (SF) OAEs were recorded over a broad range of stimulus levels and frequencies. Individual I/O and transfer functions were generated for both emission types in each ear, and OAE peak strength, compression threshold, and rate of compression were calculated. These combined SFOAE and DPOAE features in normal and hearing-impaired ears may provide a potentially informative and novel index of hearing loss. This is an initial step toward utilizing OAE source in characterizing cochlear function and dysfunction.

  2. Design study for asteroidal exploitation

    NASA Astrophysics Data System (ADS)

    Adams, Carl; Blissit, Jim; Jarrett, Dave; Sanner, Rob; Yanagawa, Koji

    1985-08-01

    A systematic approach to asteroidal exploitation for the 1990 to 2010 time frame is presented as an initial step toward expanding the use of space beyond the space station by providing a source of lower cost materials. With only a limited amount of information known about the asteroids, reconnaissance and exploration phases to determine the exact locations and compositions of several earth-approaching asteroids are required. Earth-based telescopes are used to locate and study the asteroids, while unmanned probes will return samples of asteroidal material to earth for analysis. After these phases are completed, the retrieval of a 35,000 metric ton piece of the asteroid Anteros is undertaken. A cargo transporter uses magnetoplasmadynamic (MPD) arcjets outbound and a mass-driver using asteroidal material inbound. A crew ship uses ion engines. Low thrust trajectories are used for both spacecraft. A materials processing facility will manufacture propellant pellets and retrieve non-propellant materials for spacecraft use. The cost is 1/10th that to transport the same materials from earth to high earth orbit. The project will cost 25 percent less if done in conjunction with a lunar and Martian base.

  3. Evolutionary avenues for, and constraints on, the transmission of frog lung flukes (Haematoloechus spp.) in dragonfly second intermediate hosts.

    PubMed

    Bolek, Matthew G; Janovy, John

    2007-06-01

    Metacercariae survival patterns and their distribution in second intermediate odonate hosts were examined for 4 species of frog lung flukes. Surveys of aquatic larvae and recently emerged teneral dragonflies and damselflies indicated that prevalence and mean abundance of Haematoloechus spp. metacercariae were significantly lower in teneral dragonflies than larval dragonflies, while there was no significant difference in prevalence or mean abundance of Haematoloechus spp. metacercariae among larval and teneral damselflies. Experimental infections of dragonflies indicated that metacercariae of Haematoloechus coloradensis and Haematoloechus complexus were located in the head, thorax, and branchial basket of dragonflies, whereas metacercariae of Haematoloechus longiplexus and Haematoloechus parviplexus were restricted to the branchial basket of these hosts. Metacercariae of H. coloradensis, H. complexus, and H. longiplexus infected the head, thorax, and abdomen of damselflies, but these insects were resistant to infection with H. parviplexus. Subsequent metamorphosis experiments on experimentally infected dragonflies indicated that most metacercariae of H. longiplexus were lost from the branchial basket during metamorphosis, but most metacercariae of H. coloradensis, H. complexus, and H. parviplexus survived dragonfly metamorphosis. These observations suggest that the observed ecological host specificity of H. longiplexus in semiterrestrial leopard frogs may be due to few metacercariae of H. longiplexus reaching these frogs in a terrestrial environment. Because of the uncertain validity of Haematoloechus varioplexus as a distinct species from its synonym H. parviplexus, their morphological characters were reevaluated. The morphological data on H. varioplexus and H. parviplexus indicate that they differ in their acetabulum length and width, ovary shape, testes length, and egg length and width. Experimental infections of plains leopard frogs, northern leopard frogs, and

  4. Intestinal and liver flukes of birds of prey (Accipitriformes, Falconiformes, Strigiformes) from Slovakia: uniform or diverse compound?

    PubMed

    Komorová, Petronela; Sitko, Jiljí; Špakulová, Marta; Hurníková, Zuzana

    2016-07-01

    During 2012-2014 up to 286 birds of the orders Falconiformes (5 species), Accipitriformes (11 species), and Strigiformes (7 species) were examined for trematodes and this represents the first detailed study in Slovakia. A total of 12 trematode species belonging to the families Diplostomidae, Cyathocotylidae, Strigeidae, and Opisthorchiidae were identified. Rare infections were found in falcons where only two species (40 %) and three of 85 examined birds (3.5 %) were infected with a low range of two to four worms of generalists Strigea falconis or Plagiorchis elegans. Contrary to that, ten accipitriformes species (90.9 %) and 63 of 156 bird individuals (40.4 %) were infected with nine flukes: Conodiplostomum perlatum, Conodiplostomum spathula, Neodiplostomum attenuatum, Neodiplostomum spathoides, Parastrigea flexilis, Strigea falconis, Strigea vandenbrokae, Paracoenogonimus ovatus, and Metorchis bilis. S. falconis and N. attenuatum were the most frequent, occurring in parallel in eight and four bird species, in numbers up to 575 and 224. The intensity of infection with other fluke species was low ranging from one to 13 worms. Three owl (Strigiformes) representatives (42.9 %) were exclusive hosts for Neodiplostomum canaliculatum and Strigea strigis, and the proportion of positive and dissected individual birds was 10:45 (22.2 %). Both trematodes occurred in two or three owl species. In conclusion, apparent dissimilarity of trematode load of three unrelated lines of falcons, eagles, and owls was revealed. The present study extends our knowledge on the composition of the trematode fauna in Slovakia as all species except S. falconis and P. elegans that represent new host and species records in Slovakia.

  5. Stellantchasmus falcatus (Digenea: Heterophyidae) in Cambodia: Discovery of Metacercariae in Mullets and Recovery of Adult Flukes in an Experimental Hamster

    PubMed Central

    Chai, Jong-Yil; Sohn, Woon-Mok; Na, Byoung-Kuk; Jeoung, Hoo-Gn; Sinuon, Muth; Socheat, Duong

    2016-01-01

    Stellantchasmus falcatus (Digenea: Heterophyidae) is first reported from Cambodia through recovery of the metacercariae from mullet fish and adult flukes from an experimentally infected hamster. We purchased 7 mullets, Chelon macrolepis, in a local market of Phnom Penh, Cambodia, and each of them was examined by the artificial digestion method on May 2010. The metacercariae of S. falcatus were detected in all mullets (100%) examined, and their average density was 177 per fish. They were elliptical, 220×168 μm in average size. They were orally infected to an hamster to obtain adult flukes. Adults recovered at day 10 post infection were observed with a light microscope and a scanning electron microscope (SEM). They were small, 450×237 μm in average size, had a small oral sucker (41×50 μm), subglobular pharynx (29×21 μm), slender esophagus (57 μm), long and thick-walled expulsor (119×32 μm), spherical ovary (58×69 μm), and 2 ovoid testes (right: 117×74 μm; left: 114×63 μm). Eggs were small, yellow, and 23×12 μm in average size. In SEM observations, tegumental spines were densely distributed on the whole tegument, and single small type I sensory papillae were distributed around the lip of oral sucker. The small ventral sucker was dextrally located and had 8 type I sensory papillae on the left margin. It has been first confirmed in the present study that the mullet, C. macrolepis, is playing the role of a second intermediate host of S. falcatus in Cambodia. PMID:27658608

  6. Retrotransposon OV-RTE-1 from the carcinogenic liver fluke Opisthorchis viverrini: potential target for DNA-based diagnosis.

    PubMed

    Thi Phung, Luyen; Loukas, Alex; Brindley, Paul J; Sripa, Banchob; Laha, Thewarach

    2014-01-01

    Infections by the fish-borne liver flukes Opisthorchis viverrini and Clonorchis sinensis can lead to bile duct cancer. These neglected tropical disease pathogens occur in East Asia, with O. viverrini primarily in Thailand and Laos and C. sinensis in Cambodia, Vietnam, and China. Genomic information about these pathogens holds the potential to improve disease treatment and control. Transcriptome analysis indicates that mobile genetic elements are active in O. viverrini, including a novel non-Long Terminal Repeat (LTR) retrotransposon. A consensus sequence of this element, termed OV-RTE-1, was assembled from expressed sequence tags and PCR amplified genomic DNA. OV-RTE-1 was 3330 bp in length, encoded 1101 amino acid residues and exhibited hallmark structures and sequences of non-LTR retrotransposons including a single open reading frame encoding apurinic-apyrimidinic endonuclease (EN) and reverse transcriptase (RT). Phylogenetic analyses confirmed that OV-RTE-1 was member of the RTE clade of non-LTR retrotransposons. OV-RTE-1 is the first non-LTR retrotransposon characterized from the trematode family Opisthorchiidae. Sequences of OV-RTE-1 were targeted to develop a diagnostic tool for detection of infection by O. viverrini. PCR specific primers for detection of O. viverrini DNA showed 100% specificity and sensitivity for detection of as little as 5 fg of O. viverrini DNA whereas the PCR based approach showed 62% sensitivity and 100% specificity with clinical stool samples. The OV-RTE-1 specific PCR could be developed as a molecular diagnostic for Opisthorchis infection targeting parasite eggs in stool samples, especially in regions of mixed infection of O. viverrini and/or C. sinensis and minute intestinal flukes.

  7. EFFECT OF THE FILAMENTOUS FUNGUS MUCOR CIRCINELLOIDES ON THE DEVELOPMENT OF EGGS OF THE RUMEN FLUKE CALICOPHORON DAUBNEYI (PARAMPHISTOMIDAE).

    PubMed

    Arroyo, Fabià  N; Hernà  Ndez, Josà  à  Ngel; Cazapal-Monteiro, Cristiana Filipa; Pedreira, Josà Â; Sanchà  S, Jaime; Romasanta, à  Ngel; Sã  Nchez-Andrade, Rita; Paz-Silva, Adolfo; Arias, Marà  A Sol

    2017-02-06

    Ruminants infected by Paramphistomidae flukes shed eggs in the feces, which pass through different stages in the environment until the infective stages (metacercariae) are reached. The activity of the soil fungus Mucor circinelloides on the development of eggs of the rumen fluke Calicophoron daubneyi was presently tested with 3 probes, i.e., in Petri plates, feces and an aqueous environment (tubes). The effect of the fungus was assessed by recording the numbers of undeveloped, non-viable and embryonated eggs. Non-viable eggs were considered when vacuolization occurred, the inner structures were not clearly observed, the egg-shell was broken, and/or the embryo inside was destroyed. By considering the ability of hyphae of M. circinelloides to develop in the presence of C. daubneyi eggs, attach to their surface, penetrate and destroy the inner embryo, this ovicidal effect was classified as type 3. After a period of 50 days, the percentage of undeveloped eggs in the feces of infected cattle was 40%; furthermore, 27% eggs were non-viable, and 33% were embryonated (1 miracidium inside). The addition of 4 doses of M. circinelloides spores directly onto the feces resulted in 9-31% undeveloped eggs, 38-60% non-viable eggs, and 9-21% embryonated eggs, and no statistical significances were obtained among the different doses. Placing the eggs of C. daubneyi into an aqueous solution containing 107 spores M. circinelloides/ml for 29 days resulted in 43% undeveloped eggs, 40% non-viable eggs, and 17% embryonated eggs, whereas in the controls, the percentages were 48%, 12%, and 40%, respectively. These data demonstrate the usefulness of the spores of the fungus M. circinelloides in limiting the development of the eggs of the trematode Calicophoron daubneyi.

  8. The effect of the hydrogen ionophore closantel upon the pharmacology and ultrastructure of the adult liver fluke Fasciola hepatica.

    PubMed

    Skuce, P J; Fairweather, I

    1990-01-01

    The present study describes the effects of the H+ ionophore and anthelmintic closantel upon the in vitro motility and in vivo ultrastructure of the liver fluke, Fasciola hepatica. At a concentration of 50 micrograms/ml, closantel caused an initial stimulation, then suppression of activity, which was accompanied by an increase in muscle tone and led to a spastic paralysis within 2 h. The pattern of response was similar at lower concentrations, although the initial stimulation was not always evident, but the onset of paralysis could be reached more quickly. Scanning electron microscopy revealed gross surface damage from 24 h onwards in vivo, in the form of erosion of the anterior and posterior extremities of the fluke and large-scale sloughing of the tegument on both dorsal and ventral surfaces. Tegumental changes prior to sloughing included some swelling of the basal infolds and an apical accumulation of T1 secretory bodies. In the underlying tegumental cells there was reduced secretory activity and the mitochondria were consistently swollen and deformed. Reduced secretory activity was a feature of the gastrodermal cells as well; these cells were characterized by swollen, electron-lucent mitochondria, vesiculated GER cisternae and apical blebbing of packets of cytoplasm. The vitelline follicles became severely disrupted as a result of the breakdown of the nurse cell cytoplasm. The stem and intermediate type 1 (It1) cells rounded up and showed nuclear abnormalities. There did not appear to be a severe disruption of shell protein production in the intermediate vitelline cells, but there was a noticeable absence of glycogen in the mature vitelline cells. The effects of closantel are discussed in relation to its proposed mode of action as an uncoupler of oxidative phosphorylation.

  9. An integrated pipeline for next generation sequencing and annotation of the complete mitochondrial genome of the giant intestinal fluke, Fasciolopsis buski (Lankester, 1857) Looss, 1899

    PubMed Central

    Biswal, Devendra Kumar; Ghatani, Sudeep; Shylla, Jollin A.; Sahu, Ranjana; Mullapudi, Nandita

    2013-01-01

    Helminths include both parasitic nematodes (roundworms) and platyhelminths (trematode and cestode flatworms) that are abundant, and are of clinical importance. The genetic characterization of parasitic flatworms using advanced molecular tools is central to the diagnosis and control of infections. Although the nuclear genome houses suitable genetic markers (e.g., in ribosomal (r) DNA) for species identification and molecular characterization, the mitochondrial (mt) genome consistently provides a rich source of novel markers for informative systematics and epidemiological studies. In the last decade, there have been some important advances in mtDNA genomics of helminths, especially lung flukes, liver flukes and intestinal flukes. Fasciolopsis buski, often called the giant intestinal fluke, is one of the largest digenean trematodes infecting humans and found primarily in Asia, in particular the Indian subcontinent. Next-generation sequencing (NGS) technologies now provide opportunities for high throughput sequencing, assembly and annotation within a short span of time. Herein, we describe a high-throughput sequencing and bioinformatics pipeline for mt genomics for F. buski that emphasizes the utility of short read NGS platforms such as Ion Torrent and Illumina in successfully sequencing and assembling the mt genome using innovative approaches for PCR primer design as well as assembly. We took advantage of our NGS whole genome sequence data (unpublished so far) for F. buski and its comparison with available data for the Fasciola hepatica mtDNA as the reference genome for design of precise and specific primers for amplification of mt genome sequences from F. buski. A long-range PCR was carried out to create an NGS library enriched in mt DNA sequences. Two different NGS platforms were employed for complete sequencing, assembly and annotation of the F. buski mt genome. The complete mt genome sequences of the intestinal fluke comprise 14,118 bp and is thus the shortest

  10. The exploitation of Gestalt principles by magicians.

    PubMed

    Barnhart, Anthony S

    2010-01-01

    Magicians exploit a host of psychological principles in deceiving their audiences. Psychologists have recently attempted to pinpoint the most common psychological tendencies exploited by magicians. This paper highlights two co-occurring principles that appear to be the basis for many popular magic tricks: accidental alignment and good continuation.

  11. Transitioning from AOP to IATA - Exploiting mechanistic ...

    EPA Pesticide Factsheets

    Slide presentation at satellite meeting of the QSAR2016 Meeting on How to Transition from AOP to IATA-Exploiting mechanistic insight for practical decision making. . Slide presentation at satellite meeting of the QSAR2016 Meeting on How to Transition from AOP to IATA-Exploiting mechanistic insight for practical decision making. .

  12. Fluke abundance versus host age for an invasive trematode (Dicrocoelium dendriticum) of sympatric elk and beef cattle in southeastern Alberta, Canada.

    PubMed

    Beck, Melissa A; Goater, Cameron P; Colwell, Douglas D; van Paridon, Bradley J

    2014-12-01

    Epidemiological parameters such as transmission rate, rate of parasite-induced host mortality, and rate of development of host defenses can be assessed indirectly by characterizing the manner in which parasite burdens change with host age. For parasites that are host generalists, estimates of these important parameters may be host-species dependent. In a cross-sectional study, we determined age-abundance profiles of infection in samples of sympatric free-ranging elk and domestic cattle infected with the lancet liver fluke, Dicrocoelium dendriticum. This parasite was introduced into Cypress Hills Provincial Park in southeastern Alberta, Canada in the mid 1990s, and now occurs in 60-90% of co-grazing elk and beef cattle examined at necropsy. The livers of 173 elk were made available by hunters during the 1997-2011 hunting seasons and livers from 35 cattle were purchased from ranchers. In elk, median worm abundance peaked in 6-24 month-olds (median = 72, range = 0-1006) then significantly declined to <10 worms/host in 10-16 year olds. The decline in fluke burden with age is not consistent with an age-related decline in exposure to metacercariae in intermediate hosts and high rates of fluke-induced host mortality are unlikely. Rather, the pattern of peak fluke burdens in elk calves and juveniles, followed by a decline in older animals is consistent with the development of a protective immune response in older hosts. There was no pattern of worm accumulation or decline in sympatric cattle, although statistical power to detect a significant effect was low. These results highlight the complexity and context-dependent nature of epidemiological processes in multi-host systems.

  13. Characterisation of a novel panel of polymorphic microsatellite loci for the liver fluke, Fasciola hepatica, using a next generation sequencing approach.

    PubMed

    Cwiklinski, Krystyna; Allen, Katherine; LaCourse, James; Williams, Diana J; Paterson, Steve; Hodgkinson, Jane E

    2015-06-01

    The liver fluke, Fasciola hepatica is an economically important pathogen of sheep and cattle and has been described by the WHO as a re-emerging zoonosis. Control is heavily reliant on the use of drugs, particularly triclabendazole and as a result resistance has now emerged. The population structure of F. hepatica is not well known, yet it can impact on host-parasite interactions and parasite control with drugs, particularly regarding the spread of triclabendazole resistance. We have identified 2448 potential microsatellites from 83 Mb of F. hepatica genome sequence using msatfinder. Thirty-five loci were developed and optimised for microsatellite PCR, resulting in a panel of 15 polymorphic loci, with a range of three to 15 alleles. This panel was validated on genomic DNA from 46 adult F. hepatica; 38 liver flukes sourced from a Northwest abattoir, UK and 8 liver flukes from an established isolate (Shrewsbury; Ridgeway Research). Evidence for null alleles was found at four loci (Fh_1, Fh_8, Fh_13 and Fh_14), which showed markedly higher levels of homozygosity than the remaining 11 loci. Of the 38 liver flukes isolated from cattle livers (n=10) at the abattoir, 37 genotypes were identified. Using a multiplex approach all 15 loci could be amplified from several life cycle stages that typically yield low amounts of DNA, including metacercariae, the infective life cycle stage present on pasture, highlighting the utility of this multiplex microsatellite panel. This study reports the largest panel of microsatellite markers available to date for population studies of F. hepatica and the first multiplex panel of microsatellite markers that can be used for several life cycle stages.

  14. Fluke abundance versus host age for an invasive trematode (Dicrocoelium dendriticum) of sympatric elk and beef cattle in southeastern Alberta, Canada

    PubMed Central

    Beck, Melissa A.; Goater, Cameron P.; Colwell, Douglas D.; van Paridon, Bradley J.

    2014-01-01

    Epidemiological parameters such as transmission rate, rate of parasite-induced host mortality, and rate of development of host defenses can be assessed indirectly by characterizing the manner in which parasite burdens change with host age. For parasites that are host generalists, estimates of these important parameters may be host-species dependent. In a cross-sectional study, we determined age–abundance profiles of infection in samples of sympatric free-ranging elk and domestic cattle infected with the lancet liver fluke, Dicrocoelium dendriticum. This parasite was introduced into Cypress Hills Provincial Park in southeastern Alberta, Canada in the mid 1990s, and now occurs in 60–90% of co-grazing elk and beef cattle examined at necropsy. The livers of 173 elk were made available by hunters during the 1997–2011 hunting seasons and livers from 35 cattle were purchased from ranchers. In elk, median worm abundance peaked in 6–24 month-olds (median = 72, range = 0–1006) then significantly declined to <10 worms/host in 10–16 year olds. The decline in fluke burden with age is not consistent with an age-related decline in exposure to metacercariae in intermediate hosts and high rates of fluke-induced host mortality are unlikely. Rather, the pattern of peak fluke burdens in elk calves and juveniles, followed by a decline in older animals is consistent with the development of a protective immune response in older hosts. There was no pattern of worm accumulation or decline in sympatric cattle, although statistical power to detect a significant effect was low. These results highlight the complexity and context-dependent nature of epidemiological processes in multi-host systems. PMID:25426422

  15. Effects of parenteral administration of doramectin or a combination of ivermectin and clorsulon on control of gastrointestinal nematode and liver fluke infections and on growth performance in cattle.

    PubMed

    Loyacano, A F; Skogerboe, T L; Williams, J C; DeRosa, A A; Gurie, J A; Shostrom, V K

    2001-05-01

    To compare effects of an injectable doramectin preparation with those of an injectable ivermectin-clorsulon preparation on control of gastrointestinal nematodes and liver flukes and on growth performance in cattle. Randomized complete block design. 60 crossbred calves. Calves (20/treatment group) were treated with doramectin or ivermectin-clorsulon or were not treated. Fecal samples were collected for nematode and Fasciola hepatica egg counts on day 0 and for up to 140 days after treatment. Cattle were weighed before treatment and at 28-day intervals until day 140. From day 7 through day 49, nematode egg counts for calves treated with doramectin or with ivermectin-clorsulon were significantly lower than those for untreated control calves. As the study progressed beyond day 56, the percentages of cattle with fluke eggs in their feces increased, but differences in regard to these percentages were not detected among the 3 groups. Average daily gain for the doramectin-treated cattle (0.79 kg/d [1.74 lb/d]) was significantly greater than that for the cattle treated with ivermectin-clorsuIon (0.71 kg/d [1.56 lb/d]); values for both groups were significantly greater than that for the control cattle (0.62 kg/d [1.37 lb/d]). Results suggest that doramectin had a greater impact on subclinical gastrointestinal tract parasitism in calves, as demonstrated by growth performance, than did ivermectin-clorsulon. In the Gulf Coast region of the United States, spring-born nursing beef calves may have minimal grazing exposure to F hepatica during the peak fluke transmission period; therefore, mature fluke burdens may be negligible at the beginning of the fall season.

  16. A New Measure of Interpersonal Exploitativeness

    PubMed Central

    Brunell, Amy B.; Davis, Mark S.; Schley, Dan R.; Eng, Abbey L.; van Dulmen, Manfred H.M.; Wester, Kelly L.; Flannery, Daniel J.

    2013-01-01

    Measures of exploitativeness evidence problems with validity and reliability. The present set of studies assessed a new measure [the Interpersonal Exploitativeness Scale (IES)] that defines exploitativeness in terms of reciprocity. In Studies 1 and 2, 33 items were administered to participants. Exploratory and Confirmatory Factor Analysis demonstrated that a single factor consisting of six items adequately assess interpersonal exploitativeness. Study 3 results revealed that the IES was positively associated with “normal” narcissism, pathological narcissism, psychological entitlement, and negative reciprocity and negatively correlated with positive reciprocity. In Study 4, participants competed in a commons dilemma. Those who scored higher on the IES were more likely to harvest a greater share of resources over time, even while controlling for other relevant variables, such as entitlement. Together, these studies show the IES to be a valid and reliable measure of interpersonal exploitativeness. The authors discuss the implications of these studies. PMID:23755031

  17. Development of high-resolution melting (HRM) analysis for population studies of Fascioloides magna (Trematoda: Fasciolidae), the giant liver fluke of ruminants.

    PubMed

    Radvánský, Ján; Bazsalovicsová, Eva; Králová-Hromadová, Ivica; Minárik, Gabriel; Kádaši, Ludevít

    2011-01-01

    The high-resolution melting (HRM) technique was successfully optimized as fast and effective method for population study of digenetic fluke, Fascioloides magna (Trematoda: Fasciolidae), originally North American liver parasite of free-living and domestic ruminants. Previously selected variable region (439 bp) of mitochondrial cytochrome c oxidase subunit I (cox1) of 249 fluke individuals from enzootic European and North American regions were sequenced and mutually compared. The sequence analysis of partial cox1 revealed presence of seven structurally different haplotypes. Based on the sequence structure and alignments of six of them (Ha1-Ha6), three internal probes were designed and applied in HRM-based haplotype determination of all F. magna specimens. HRM analysis, performed with three designed probes, resulted in classification of samples into the seven haplogroups, equally with their assortment according to the sequence analysis. The representative of the haplotype, which was not involved in probe design (Ha7), was characterized by a unique melting curve shape as well. This provided an evidence of optimally settled conditions in HRM assay and indicated a probability of successful discrimination of novel haplotypes in future population studies on F. magna. The successful optimization of HRM method stands for an opportunity of detection of genetically unknown North American variants of F. magna and promises its application as fast and cheap screening technique for phylogeography studies of the giant liver fluke on its original continent.

  18. Pharmacological and morphological characteristics of the muscular system of the giant liver fluke (Fascioloides magna - Bassi 1875).

    PubMed

    Trailović, Saša M; Marinković, Darko; Trailović, Jelena Nedeljković; Milovanović, Mirjana; Marjanović, Djordje S; Aničić, Milan R

    2015-12-01

    Motility is required for feeding, reproduction and maintenance of the fluke in the host's liver. According to that, the neuromuscular system can be an attractive drugable target for chemotherapy. Musculature of the Fascioloides magna is organized into three layers, an outer circular layer, beneath this layer the longitudinal layer, and third, the oblique, or diagonal layer underlies the longitudinal layer. In our study, the administration of atropine or caffeine did not cause classic muscle contractions of F. magna muscle strips. However, the Electrical Field Stimulation (EFS) induced stable and repeatable contractions, which enabled us to examine their sensitivity to the various substances. Acetylcholine (ACh) (300 μM and 1 mM), caused only a slight relaxation, without affecting the amplitude of spontaneous contractions or the amplitude of contractions induced by EFS. Contrary to that, atropine (100 μM) caused a significant increase in the basal tone and an increase of EFS-induced contractions. If acetylcholine is an inhibitory neurotransmitter in trematodes, the described effects of atropine are achieved by the blockade of inhibitory neurotransmission. On the other hand, with respect to the process of excitation-contraction coupling, the plant alkaloid ryanodine (30 μM) significantly reduced the basal tone, as well as EFS-induced contractions of F. magna muscle strips. Ryanodine inhibited the potentiating effect of atropine on the basal tone and contractions caused by EFS, which indicates that the contractile effect of atropine is dependent on Ca(++) release from intracellular stores. Caffeine (500 μM) caused relaxation of fluke muscle strips and at the same time significantly enhanced the EFS-induced contractions. Both effects of caffeine can be explained by entry of extracellular Ca(++) into muscle cells. The muscle contractility of F. magna depends both on the entry of extracellular calcium, and calcium release from intracellular stores, which are

  19. Money for Blood and Markets for Blood.

    PubMed

    Derpmann, Simon; Quante, Michael

    2015-12-01

    Ontario's Bill 178 proposing a Voluntary Blood Donations Act declares the offer or acceptance of payment for the donation of blood a legal offence and makes it subject to penalty. The bill reinvigorates a fundamental debate about the ethical problems associated with the payment of money for blood. Scarcity of blood donors is a recurring problem in most health systems, and monetary remuneration of the willingness to donate blood is regularly discussed--and sometimes practiced--as a means to overcome scarcity in blood. However, making blood an object of economic exchange has long aroused ethical concerns that often refer to the specific meaning of blood. From the perspective of a modern understanding of money as a metric of economic value, the exchange of money for blood--shed or given--is seen as ethically troubling, because it appears to imply a commensurability of the value of human life and economic wealth. In this paper, we begin with a general taxonomy of the types of arguments that speak in favour or against compensating donors for giving blood. We then describe the context in which the discussion about payment for blood arises, and of the specific aims and concerns that are brought forward in this context. This is used to reconstruct the normative background that supports the rejection of payment for blood as it is envisaged in Bill 178 and the aims of the proposal. We then argue that while a payment indeed changes the nature of a blood donation in an ethically considerable way, we do not believe that decisive arguments against the monetary remuneration of blood donations can be substantiated, at least not independently of assuming specific societal circumstances. Thus it may be possible to establish a stable and safe blood supply through just gratification while at the same time taking strong provisions against social disconnection, injustice, exploitation or heteronomy.

  20. Herbivory eliminates fitness costs of mutualism exploiters.

    PubMed

    Simonsen, Anna K; Stinchcombe, John R

    2014-04-01

    A common empirical observation in mutualistic interactions is the persistence of variation in partner quality and, in particular, the persistence of exploitative phenotypes. For mutualisms between hosts and symbionts, most mutualism theory assumes that exploiters always impose fitness costs on their host. We exposed legume hosts to mutualistic (nitrogen-fixing) and exploitative (non-nitrogen-fixing) symbiotic rhizobia in field conditions, and manipulated the presence or absence of insect herbivory to determine if the costly fitness effects of exploitative rhizobia are context-dependent. Exploitative rhizobia predictably reduced host fitness when herbivores were excluded. However, insects caused greater damage on hosts associating with mutualistic rhizobia, as a consequence of feeding preferences related to leaf nitrogen content, resulting in the elimination of fitness costs imposed on hosts by exploitative rhizobia. Our experiment shows that herbivory is potentially an important factor in influencing the evolutionary dynamic between legumes and rhizobia. Partner choice and host sanctioning are theoretically predicted to stabilize mutualisms by reducing the frequency of exploitative symbionts. We argue that herbivore pressure may actually weaken selection on choice and sanction mechanisms, thus providing one explanation of why host-based discrimination mechanisms may not be completely effective in eliminating nonbeneficial partners.

  1. Global Climate Responses to Anthropogenic Groundwater Exploitation

    NASA Astrophysics Data System (ADS)

    Zeng, Y.; Xie, Z.

    2015-12-01

    In this study, a groundwater exploitation scheme is incorporated into the earth system model, Community Earth System Model 1.2.0 (CESM1.2.0), which is called CESM1.2_GW, and the climatic responses to anthropogenic groundwater withdrawal are then investigated on global scale. The scheme models anthropogenic groundwater exploitation and consumption, which are then divided into agricultural irrigation, industrial use and domestic use. A group of 41-year ensemble groundwater exploitation simulations with six different initial conditions, and a group of ensemble control simulations without exploitation are conducted using the developed model CESM1.2_GW with water supplies and demands estimated. The results reveal that the groundwater exploitation and water consumption cause drying effects on soil moisture in deep layers and wetting effects in upper layers, along with a rapidly declining groundwater table in Central US, Haihe River Basin in China and Northern India and Pakistan where groundwater extraction are most severe in the world. The atmosphere also responds to anthropogenic groundwater exploitation. Cooling effects on lower troposphere appear in large areas of North China Plain and of Northern India and Pakistan. Increased precipitation occurs in Haihe River Basin due to increased evapotranspiration from irrigation. Decreased precipitation occurs in Northern India because water vapor here is taken away by monsoon anomalies induced by anthropogenic alteration of groundwater. The local reducing effects of anthropogenic groundwater exploitation on total terrestrial water storage evinces that water resource is unsustainable with the current high exploitation rate. Therefore, a balance between slow groundwater withdrawal and rapid human economic development must be achieved to maintain a sustainable water resource, especially in over-exploitation regions such as Central US, Northern China, India and Pakistan.

  2. Evidence for high genetic diversity of NAD1 and COX1 mitochondrial haplotypes among triclabendazole resistant and susceptible populations and field isolates of Fasciola hepatica (liver fluke) in Australia.

    PubMed

    Elliott, T; Muller, A; Brockwell, Y; Murphy, N; Grillo, V; Toet, H M; Anderson, G; Sangster, N; Spithill, T W

    2014-02-24

    In recent years, the global incidence of Fasciola hepatica (liver fluke) infections exhibiting resistance to triclabendazole (TCBZ) has increased, resulting in increased economic losses for livestock producers and threatening future control. The development of TCBZ resistance and the worldwide discovery of F. hepatica population diversity has emphasized the need to further understand the genetic structure of drug susceptible and resistant Fasciola populations within Australia. In this study, the genetic diversity of liver flukes was estimated by sequencing mitochondrial DNA (mtDNA) encoding the NAD1 (530 bp) and COX1 (420 bp) genes of 208 liver flukes (F. hepatica) collected from three populations: field isolates obtained from abattoirs from New South Wales (NSW) and Victoria (Vic); three TCBZ-resistant fluke populations from NSW and Victoria; and the well-established TCBZ-susceptible Sunny Corner laboratory isolate. Overall nucleotide diversity for all flukes analysed of 0.00516 and 0.00336 was estimated for the NAD1 and COX1 genes respectively. Eighteen distinct haplotypes were established for the NAD1 gene and six haplotypes for the COX1 gene, resulting in haplotype diversity levels of 0.832 and 0.482, respectively. One field isolate showed a similar low level of haplotype diversity as seen in the Sunny Corner laboratory isolate. Analysis of TCBZ-resistant infrapopulations from 3 individual cattle grazing one property revealed considerable sequence parasite diversity between cattle. Analysis of parasite TCBZ-resistant infrapopulations from sheep and cattle revealed haplotypes unique to each host, but no significant difference between parasite populations. Fst analysis of fluke populations revealed little differentiation between the resistant and field populations. This study has revealed a high level of diversity in field and drug resistant flukes in South-Eastern Australia.

  3. Donating Blood

    MedlinePlus

    ... blood transfusion. Blood donors — especially donors with certain blood types — are always in demand. Who Can Donate Blood? ... Natural Disasters: How to Help Blood Blood Transfusions Blood Types Contact Us Print Resources Send to a Friend ...

  4. National Center for Missing and Exploited Children

    MedlinePlus

    ... Team HOPE provides peer and emotional support to families. Contact Us Legal Information DONATE Careers Site Index Copyright © 2016 National Center for Missing & Exploited Children. All rights reserved. This Web site ...

  5. Molecular identification of the Indian liver fluke, Fasciola (Trematoda: Fasciolidae) based on the ribosomal internal transcribed spacer regions.

    PubMed

    Prasad, P K; Tandon, V; Biswal, D K; Goswami, L M; Chatterjee, A

    2008-11-01

    The species of liver flukes of the genus Fasciola (Platyhelminthes: Digenea: Fasciolidae) are obligate parasitic trematodes residing in the large biliary ducts of herbivorous mammals. While Fasciola hepatica has a cosmopolitan distribution, the other major species, i.e., Fasciola gigantica is reportedly prevalent in the tropical and subtropical regions of Africa and Asia. To determine the phylogenic location of Fasciola sp. of Assam (India) origin based on rDNA molecular data, ribosomal ITS regions were sequenced and compared with other species of trematodes in the family Fasciolidae. NCBI databases were used for sequence homology analysis using BLAST and ClustalW programs. The phylogenetic trees constructed based upon the ITS (1 and 2) sequences revealed a close relationship with isolates of F. gigantica from China, Indonesia, Japan, Egypt, and Zambia, the isolate from China with significant bootstrap values being the closest. Using the novel approach of molecular morphometrics that is based on ITS2 secondary structure homologies, phylogenetic relationships of the various isolates of fasciolid species have also been discussed. While comparing ITS1, the sequence of another Indian isolate designated as F. gigantica (accession no. EF198867) showed almost absolute match with F. hepatica. Hence, this particular isolate should be identified as F. hepatica and not F. gigantica.

  6. Landscape influence on spatial patterns of meningeal worm and liver fluke infection in white-tailed deer.

    PubMed

    Vanderwaal, Kimberly L; Windels, Steve K; Olson, Bryce T; Vannatta, J Trevor; Moen, Ron

    2015-04-01

    Parasites that primarily infect white-tailed deer (Odocoileus virginianus), such as liver flukes (Fascioloides magna) and meningeal worm (Parelaphostrongylus tenuis), can cause morbidity and mortality when incidentally infecting moose (Alces alces). Ecological factors are expected to influence spatial variation in infection risk by affecting the survival of free-living life stages outside the host and the abundance of intermediate gastropod hosts. Here, we investigate how ecology influenced the fine-scale distribution of these parasites in deer in Voyageurs National Park, Minnesota. Deer pellet groups (N = 295) were sampled for the presence of P. tenuis larvae and F. magna eggs. We found that deer were significantly more likely to be infected with P. tenuis in habitats with less upland deciduous forest and more upland mixed conifer forest and shrub, a pattern that mirrored microhabitat differences in gastropod abundances. Deer were also more likely to be infected with F. magna in areas with more marshland, specifically rooted-floating aquatic marshes (RFAMs). The environment played a larger role than deer density in determining spatial patterns of infection for both parasites, highlighting the importance of considering ecological factors on all stages of a parasite's life cycle in order to understand its occurrence within the definitive host.

  7. Adult Opisthorchis felineus major protein fractions deduced from transcripts: comparison with liver flukes Opisthorchis viverrini and Clonorchis sinensis.

    PubMed

    Pomaznoy, Mikhail; Tatkov, Sergey; Katokhin, Alexey; Afonnikov, Dmitry; Babenko, Vladimir; Furman, Dagmara; Brusentsov, Ilya; Belavin, Pavel; Najakshin, Alexandr; Guselnikov, Sergey; Vasiliev, Gennady; Sivkov, Anton; Prokhortchouk, Egor; Skryabin, Konstantin; Mordvinov, Viatcheslav

    2013-10-01

    The epidemiologically important liver flukes Opisthorchis felineus, Opisthorchis viverrini, and Clonorchis sinensis are of interest to health professionals, epidemiologists, pharmacologists, and molecular biologists. Recently the transcriptomes of the latter two species were intensively investigated. However our knowledge on molecular biology of O. felineus is scarce. We report the first results of the O. felineus transcriptome analysis. We isolated and annotated a total of 2560 expressed sequence tag (EST) sequences from adult O. felineus (deposited within the database of expressed sequence tags (dbEST), under accession numbers GenBank: JK624271-JK626790, JK006511-JK006547, JK649790-JK649792). Clustering and analysis resulted in the detection of 267 contigs. Of the protein sequences deduced from these, 82% had homologs in the NCBI (nr) protein database and 63% contained conserved domains, allowing the functions to be interpreted using the Gene Ontology terms. Comprehensive analysis of Opisthorchiidae- and Trematoda-specific substitutions within amino acid sequences deduced for the proteins myoglobin, vitelline precursor protein, cathepsin F, and 28kDa glutathione transferase was carried out. The gene set of the 32 ribosomal proteins for the three Opisthorchiidae species with the addition of available Schistosoma and Fasciola orthologs was created and is provided in the supplementary. The orthologous gene set created was used for inferring phylogeny within the Trematoda with special attention to interrelations within the Opisthorchiidae. The phylogenetic analysis revealed a closer relationship between C. sinensis and O. viverrini and some divergence of O. felineus from either O. viverrini or C. sinensis.

  8. Description of a new lung fluke species, Paragonimus vietnamensis sp. nov. (Trematoda, Paragonimidae), found in northern Vietnam.

    PubMed

    Doanh, Pham Ngoc; Shinohara, Akio; Horii, Yoichiro; Habe, Shigehisa; Nawa, Yukifumi; Le, Nguyen Thi

    2007-11-01

    Based on morphology of metacercariae and adult worms together with molecular data from our previous study, we describe herein a new lung fluke species named Paragonimus vietnamensis sp. nov. Metacercariae of this new species is round and extremely large in size (nearly 800 mum in diameter) having a fragile outer cyst of variable thickness and a thin fragile inner cyst. There are little or no space between metacercaria and the inner cyst wall. These and other morphological features of metacercariae of P. vietnamensis sp. nov. are not completely identical with but have some similarities with those of P. microrchis, P. proliferus, or P. menglaensis. On the other hand, adult worms obtained by experimental infection of these large metacercariae are oval in shape, having a ventral sucker slightly larger than the oral one, and having singly arranged relatively short cuticular spines. These morphological features of adult worms are partly similar to but not identical with those of P. microrchis, P. skrjabini, P. yunnanenis, P. xiangshanensis, or P. harinasutai. Taken these morphological data and our previous molecular phylogenetic analyses of ITS2 and CO1 sequences of metacercariae and adult worms together, P. vietnamensis sp. nov. is different from any other known Paragonimus spp.

  9. Activity of tribendimidine and praziquantel combination therapy against the liver fluke Opisthorchis viverrini in vitro and in vivo.

    PubMed

    Keiser, J; Adelfio, R; Vargas, M; Odermatt, P; Tesana, S

    2013-06-01

    Opisthorchiasis, caused by the liver fluke Opisthorchis viverrini, a food-borne trematode, is an important public health problem; however, only a single drug, praziquantel is available. We investigated tribendimidine-praziquantel combinations against O. viverrini in vitro and in vivo. The IC50 values of 0.16 μg/ml and 0.05 μg/ml were determined for praziquantel and tribendimidine, respectively, against adult O. viverrini in vitro. When O. viverrini was exposed to both drugs simultaneously (using a drug ratio based on the IC50 (1:3.2)) a synergistic effect was calculated (combination index (CI) at the IC50= 0.7). A similar result was observed when drug addition in vitro was spaced by the respective half-lives of the drugs (a CI of 0.78 at the IC50 for tribendimidine followed by praziquantel and a CI of 0.47 at the IC50 for praziquantel followed by tribendimidine). In vivo median-effect dose (ED50) values of 191 mg/kg and 147 mg/kg were calculated for praziquantel and tribendimidine, respectively. Low to moderate worm burden reductions (38-62%) were observed in O. viverrini infected hamsters when both drugs were administered simultaneously or on subsequent days, pointing to antagonistic effects in vivo. Further studies are necessary to understand the striking differences between the in vitro and in vivo observations using combinations of praziquantel and tribendimidine on O. viverrini.

  10. Microarray analysis of rat immune responses to liver fluke infection following vaccination with Fasciola hepatica phosphoglycerate kinase.

    PubMed

    Wesołowska, Agnieszka; Jaros, Sławomir; Norbury, Luke J; Jaros, Dorota; Zygner, Wojciech; Wędrychowicz, Halina

    2013-05-01

    Fasciolosis is a considerable veterinary problem, causing significant economic losses to livestock production and the food industry. Research in the area of Fasciola hepatica infection immunology is necessary to improve our knowledge about immunological mechanism evoked by the parasite and to develop new control strategies against liver fluke. In this present paper we analyzed the expression levels of cytokines in rats infected with F. hepatica following immunization with F. hepatica phosphoglycerate kinase - a novel vaccine antigen. Immune response analysis using microarray was undertaken six weeks after infection. Expression levels of INF-γ and IL-4, which are characteristic cytokines secreted during Th1-like and Th2-like immune responses, respectively, were unchanged in vaccinated animals as compared to control animals. This indicates the vaccine did not influence the major modulation of immune responses typically observed during Fasciola infections, however, other subtle but significant variations were observed that indicated altered inflammatory and possibly T helper cell responses. A significant rise in IL-12α chain expression levels was observed. Expression levels of TNF-α and some related molecules, such as ADAM17, FasL, CD40 and TRAF3 were also elevated. Expression levels of molecules involved in IL-1 signaling pathways were reduced, although a rise in IL-1α expression was noted. Copyright © 2013 Elsevier Inc. All rights reserved.

  11. Distribution and habitats of the snail Lymnaea truncatula, intermediate host of the liver fluke Fasciola hepatica, in South Africa.

    PubMed

    de Kock, K N; Wolmarans, C T; Bornman, M

    2003-12-01

    This paper focuses on the geographical distribution and habitats of Lymnaea truncatula, the intermediate, snail host of the liver fluke, Fasciola hepatica, as reflected by the 723 samples in the database of the National Freshwater Snail Collection, Potchefstroom, South Africa. The 221 different loci (1/16-degree squares) on record reflect an extensive but discontinuous distribution, except in Lesotho and in parts of the Mpumalanga, Gauteng and North West provinces of South Africa. Although recorded from 12 different types of waterbody, it was mostly (42.0%) recovered from swamps. Most samples (45.8%) were collected in habitats with slow-flowing water. A muddy substratum was recorded for 62.5% of the samples. Most samples (86.3%) were collected in habitats with a mean annual air temperature of 10-20 degrees C, and more than 69% came from localities with a mean annual rainfall of 600-900 mm. An integrated decision tree constructed from the data indicated that temperature and types of waterbody play a decisive role in determining the presence of L. truncatula in a given area. A temperature index calculated for all mollusc species ranked L. truncatula second in a total of 53 species according to its association with low temperatures. It remains to be established whether its distribution is indeed discontinuous, and whether its preference for a particular habitat, amphibious habits and ability to aestivate could have resulted in some populations having been overlooked during surveys.

  12. Exploitations and their complications: the necessity of identifying the multiple forms of exploitation in pharmaceutical trials.

    PubMed

    Snyder, Jeremy

    2012-06-01

    Human subject trials of pharmaceuticals in low and middle income countries (LMICs) have been associated with the moral wrong of exploitation on two grounds. First, these trials may include a placebo control arm even when proven treatments for a condition are in use in other (usually wealthier) parts of the world. Second, the trial researchers or sponsors may fail to make a successful treatment developed through the trial available to either the trial participants or the host community following the trial. Many commentators have argued that a single form of exploitation takes place during human subject research in LMICs. These commentators do not, however, agree as to what kind of moral wrong exploitation is or when exploitation is morally impermissible. In this paper, I have two primary goals. First, I will argue for a taxonomy of exploitation that identifies three distinct forms of exploitation. While each of these forms of exploitation has its critics, I will argue that they can each be developed into plausible accounts of exploitation tied to different vulnerabilities and different forms of wrongdoing. Second, I will argue that each of these forms of exploitation can coexist in single situations, including human subject trials of pharmaceuticals. This lesson is important, since different forms of exploitation in a single relationship can influence, among other things, whether the relationship is morally permissible. © 2010 Blackwell Publishing Ltd.

  13. Exploitation in International Paid Surrogacy Arrangements

    PubMed Central

    Wilkinson, Stephen

    2015-01-01

    Abstract Many critics have suggested that international paid surrogacy is exploitative. Taking such concerns as its starting point, this article asks: (1) how defensible is the claim that international paid surrogacy is exploitative and what could be done to make it less exploitative? (2) In the light of the answer to (1), how strong is the case for prohibiting it? Exploitation could in principle be dealt with by improving surrogates' pay and conditions. However, doing so may exacerbate problems with consent. Foremost amongst these is the argument that surrogates from economically disadvantaged countries cannot validly consent because their background circumstances are coercive. Several versions of this argument are examined and I conclude that at least one has some merit. The article's overall conclusion is that while ethically there is something to be concerned about, paid surrogacy is in no worse a position than many other exploitative commercial transactions which take place against a backdrop of global inequality and constrained options, such as poorly‐paid and dangerous construction work. Hence, there is little reason to single surrogacy out for special condemnation. On a policy level, the case for prohibiting international commercial surrogacy is weak, despite legitimate concerns about consent and background poverty. PMID:27471338

  14. Exploitation in International Paid Surrogacy Arrangements.

    PubMed

    Wilkinson, Stephen

    2016-05-01

    Many critics have suggested that international paid surrogacy is exploitative. Taking such concerns as its starting point, this article asks: (1) how defensible is the claim that international paid surrogacy is exploitative and what could be done to make it less exploitative? (2) In the light of the answer to (1), how strong is the case for prohibiting it? Exploitation could in principle be dealt with by improving surrogates' pay and conditions. However, doing so may exacerbate problems with consent. Foremost amongst these is the argument that surrogates from economically disadvantaged countries cannot validly consent because their background circumstances are coercive. Several versions of this argument are examined and I conclude that at least one has some merit. The article's overall conclusion is that while ethically there is something to be concerned about, paid surrogacy is in no worse a position than many other exploitative commercial transactions which take place against a backdrop of global inequality and constrained options, such as poorly-paid and dangerous construction work. Hence, there is little reason to single surrogacy out for special condemnation. On a policy level, the case for prohibiting international commercial surrogacy is weak, despite legitimate concerns about consent and background poverty.

  15. The efficacy of an ivermectin/closantel injection against experimentally induced infections and field infections with gastrointestinal nematodes and liver fluke in cattle.

    PubMed

    Borgsteede, Fred H M; Taylor, Stuart M; Gaasenbeek, Cor P H; Couper, Alistair; Cromie, Lillian

    2008-08-17

    Three studies were performed to test the efficacy of an ivermectin/closantel injection (200 microg/kg(-1) ivermectin and 5 mg/kg(-1) closantel) in cattle. Two were experimentally induced infections of Ostertagia ostertagi, Cooperia oncophora and Fasciola hepatica in calves, and the third had natural field infections in cattle with several species of gastrointestinal nematodes and F. hepatica. In the two studies with artificial infections, four groups of 8 calves were used. All calves were infected with metacercariae on Day 0. Infection with the nematodes took place on Day 33 in groups 1 and 2 and on Day 54 in groups 3 and 4. Treatment was given to calves of group 1 on Day 63 and to calves of group 3 on Day 84. Calves of groups 2 and 4 served as untreated control groups. Calves of groups 1 and 2 were sacrificed on Day 84, calves of groups 3 and 4 on Day 105. The field study was carried out on a commercial farm in the Netherlands. Six groups of cattle were used. Groups A and B consisted of 10 parasite free calves, introduced to the farm and grazed for four weeks on pastures naturally infected with gastrointestinal nematode larvae and liver fluke metacercariae. Group C were the farmers own calves (15), group D heifers (10), group E dry cows (6) and group F milking cows (20). Treatment was given to animals of group A, C, D and E 10 weeks after housing of group A and B. Animals of groups B and F served as untreated controls. Calves of groups A and B were sacrificed 14 days after treatment. The efficacy of the treatment was calculated on basis of the post-mortem fluke and nematode worm counts in the first two studies and on a combination of post-mortem fluke and nematode worm counts and faecal egg output in the field study. In the two experimental studies, the efficacy of the treatment against F. hepatica was 99.2% and 94.5% for 9-week-old flukes and 98.4% and 99.5% for 12-week-old flukes. For O. ostertagi in both studies efficacy was 100% and against C. oncophora in

  16. Rethinking exploitation: a process-centered account.

    PubMed

    Jansen, Lynn A; Wall, Steven

    2013-12-01

    Exploitation has become an important topic in recent discussions of biomedical and research ethics. This is due in no small measure to the influence of Alan Wertheimer's path-breaking work on the subject. This paper presents some objections to Wertheimer's account of the concept. The objections attempt to show that his account places too much emphasis on outcome-based considerations and too little on process-based considerations. Building on these objections, the paper develops an alternative process-centered account of the concept. This alternative account of exploitation takes as its point of departure the broadly Kantian notion that it is wrong to use another as an instrument for the advancement of one's own ends. It sharpens this slippery notion and adds a number of refinements to it. The paper concludes by arguing that process-centered accounts of exploitation better illuminate the ethical challenges posed by research on human subjects than outcome-centered accounts.

  17. The role and immunophenotypic characteristics of myofibroblasts in liver of sheep naturally infected with the lancet liver fluke (Dicrocoelium dendriticum).

    PubMed

    Kukolj, V; Aleksić-Kovačević, S; Katić-Radivojević, S; Knežević, Dj; Jovanović, M

    2015-03-15

    The main objective of our research was to examine the role and immunophenotypic characteristics of myofibroblasts in sheep liver naturally infected by the lancet liver fluke (Dicrocoelium dendriticum). In the reported study we analyzed liver samples from 20 adult sheep, 14 infected animals and 6 controls. The liver samples were fixed in 10% buffered formalin, and routinely processed and stained using hematoxylin eosin, the periodic acid-Schiff and Masson-Goldner trichrome methods. The immunohistochemical examination was carried out by the streptavidin biotin (LSAB2) method, using antibodies for α-smooth muscle actin (α-SMA), desmin and vimentin. The histopathological examination revealed liver fibrosis in 6 out of 14 (42.9%) analyzed samples, while different forms of cholangitis were observed in the remaining 8 out of 14 (57.1%). The expression of α-SMA was proven in perisinusoidal hepatic stellate cells, portal/septal myofibroblasts, and interface myofibroblasts. The degree of α-SMA expression and the number of α-SMA immunopositive cells were the most intensive in the liver with fibrosis. Desmin expression in all liver samples of infected sheep was confirmed in hepatic stellate cells and smooth muscle cells. The hepatic stellate cells, portal/septal myofibroblasts, and interface myofibroblasts reacted as vimentin positive cells. In the liver without fibrotic changes hepatic stellate cells and smooth muscle cells were desmin positive. The obtained results suggest that all populations of myofibroblasts, especially hepatic stellate cells, play an important role in the increased extracellular matrix formation during parasitic liver fibrosis in sheep naturally infected with D. dendriticum. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Development of Mitochondrial Loop-Mediated Isothermal Amplification for Detection of the Small Liver Fluke Opisthorchis viverrini (Opisthorchiidae; Trematoda; Platyhelminthes)

    PubMed Central

    Nguyen, Nga Thi Bich; Truong, Nam Hai; De, Nguyen Van

    2012-01-01

    Mitochondrial DNA sequences offer major advantages over the more usual nuclear targets for loop-mediated isothermal amplification approaches (mito-LAMP) because multiple copies occur in every cell. Four LAMP primers [F3, FIP(F1c+F2), BIP(B1c+B2), and B3] were designed based on the mitochondrial nad1 sequence of Opisthorchis viverrini and used for a highly specific assay (mito-OvLAMP) to distinguish DNA of O. viverrini from that of another opisthorchiid (Clonorchis sinensis) and other trematodes (Haplorchis pumilio, Haplorchis taichui, Fasciola hepatica, and Fasciola gigantica). Conventional PCR was applied using F3/B3 primer pairs to verify the specificity of the primers for O. viverrini DNA templates. All LAMP-positive samples could be detected with the naked eye in sunlight, by gel electrophoresis (stained with ethidium bromide), and by addition of SYBR green I to the product in sunlight or under UV light. Only DNA from O. viverrini yielded amplification products by LAMP (and by PCR verification), and the LAMP limit of detection was as little as 100 fg (10−4 ng DNA), indicating that this assay is 10 to 100 times more sensitive than PCR. Field testing was done using representative egg and metacercarial samples collected from localities where the fluke is endemic. With the advantages of simplicity, rapidity, sensitivity, and cost effectiveness, mito-OvLAMP is a good tool for molecular detection and epidemiology studies in regions or countries where O. viverrini is endemic, which can lead to more effective control of opisthorchiasis and trematodiasis. PMID:22322346

  19. Molecular identification and phylogenetic analysis of nuclear rDNA sequences among three opisthorchid liver fluke species (Opisthorchiidae: Trematoda).

    PubMed

    Kang, Seokha; Sultana, Tahera; Loktev, Valery B; Wongratanacheewin, Surasakdi; Sohn, Woon-Mok; Eom, Keeseon S; Park, Joong-Ki

    2008-06-01

    In this study, we describe the development of a fast and accurate molecular identification system for human-associated liver fluke species (Opisthorchis viverrini, Opisthorchis felineus, and Clonorchis sinensis) using the PCR-RFLP analysis of the 18S-ITS1-5.8S nuclear ribosomal DNA region. Based on sequence variation in the target rDNA region, we selected three species-specific restriction enzymes within the ITS1 regions, generating different restriction profiles among the species: MunI for O. viverrini, NheI for O. felineus, and XhoI for C. sinensis, respectively. Each restriction enzyme generated different-sized fragments specific to the species examined, but no intraspecific polymorphism or cross-reaction between the species was detected in their restriction pattern. These results indicate that PCR-linked restriction analysis of the ITS1 region allows for the rapid and reliable molecular identification among these opisthorchid taxa. In addition, phylogenetic analysis of rDNA sequences using different methods (MP, ML, NJ, and Bayesian inference) displayed O. viverrini and O. felineus as a sister group, but this relationship was not strongly supported. The failure of recovering a robust phylogeny may be due to the relatively small number of synapomorphic characters shared among the species, yielding weak phylogenetic signal. Alternatively, rapid speciation within a very short period time could be another explanation for the relatively poorly resolved relationships among these species. Our data are insufficient for discriminating between sudden cladogenesis and other potential causes of poor resolution. Further information from independent loci might help resolve this phylogeny.

  20. Development of mitochondrial loop-mediated isothermal amplification for detection of the small liver fluke Opisthorchis viverrini (Opisthorchiidae; Trematoda; Platyhelminthes).

    PubMed

    Le, Thanh Hoa; Nguyen, Nga Thi Bich; Truong, Nam Hai; De, Nguyen Van

    2012-04-01

    Mitochondrial DNA sequences offer major advantages over the more usual nuclear targets for loop-mediated isothermal amplification approaches (mito-LAMP) because multiple copies occur in every cell. Four LAMP primers [F3, FIP(F1c+F2), BIP(B1c+B2), and B3] were designed based on the mitochondrial nad1 sequence of Opisthorchis viverrini and used for a highly specific assay (mito-OvLAMP) to distinguish DNA of O. viverrini from that of another opisthorchiid (Clonorchis sinensis) and other trematodes (Haplorchis pumilio, Haplorchis taichui, Fasciola hepatica, and Fasciola gigantica). Conventional PCR was applied using F3/B3 primer pairs to verify the specificity of the primers for O. viverrini DNA templates. All LAMP-positive samples could be detected with the naked eye in sunlight, by gel electrophoresis (stained with ethidium bromide), and by addition of SYBR green I to the product in sunlight or under UV light. Only DNA from O. viverrini yielded amplification products by LAMP (and by PCR verification), and the LAMP limit of detection was as little as 100 fg (10(-4) ng DNA), indicating that this assay is 10 to 100 times more sensitive than PCR. Field testing was done using representative egg and metacercarial samples collected from localities where the fluke is endemic. With the advantages of simplicity, rapidity, sensitivity, and cost effectiveness, mito-OvLAMP is a good tool for molecular detection and epidemiology studies in regions or countries where O. viverrini is endemic, which can lead to more effective control of opisthorchiasis and trematodiasis.

  1. Modeling impacts of climate change on the potential distribution of the carcinogenic liver fluke, Opisthorchis viverrini, in Thailand.

    PubMed

    Suwannatrai, A; Pratumchart, K; Suwannatrai, K; Thinkhamrop, K; Chaiyos, J; Kim, C S; Suwanweerakamtorn, R; Boonmars, T; Wongsaroj, T; Sripa, B

    2017-01-01

    Global climate change is now regarded as imposing a significant threat of enhancing transmission of parasitic diseases. Maximum entropy species distribution modeling (MaxEnt) was used to explore how projected climate change could affect the potential distribution of the carcinogenic liver fluke, Opisthorchis viverrini, in Thailand. A range of climate variables was used: the Hadley Global Environment Model 2-Earth System (HadGEM2-ES) climate change model and also the IPCC scenarios A2a for 2050 and 2070. Occurrence data from surveys conducted in 2009 and 2014 were obtained from the Department of Disease Control, Ministry of Public Health, Thailand. The MaxEnt model performed better than random for O. viverrini with training AUC values greater than 0.8 under current and future climatic conditions. The current distribution of O. viverrini is significantly affected by precipitation and minimum temperature. According to current conditions, parts of Thailand climatically suitable for O. viverrini are mostly in the northeast and north, but the parasite is largely absent from southern Thailand. Under future climate change scenarios, the distribution of O. viverrini in 2050 should be significantly affected by precipitation, maximum temperature, and mean temperature of the wettest quarter, whereas in 2070, significant factors are likely to be precipitation during the coldest quarter, maximum, and minimum temperatures. Maps of predicted future distribution revealed a drastic decrease in presence of O. viverrini in the northeast region. The information gained from this study should be a useful reference for implementing long-term prevention and control strategies for O. viverrini in Thailand.

  2. UDP-galactose 4'-epimerase from the liver fluke, Fasciola hepatica: biochemical characterization of the enzyme and identification of inhibitors.

    PubMed

    Zinsser, Veronika L; Lindert, Steffen; Banford, Samantha; Hoey, Elizabeth M; Trudgett, Alan; Timson, David J

    2015-03-01

    Leloir pathway enzyme uridine diphosphate (UDP)-galactose 4'-epimerase from the common liver fluke Fasciola hepatica (FhGALE) was identified and characterized. The enzyme can be expressed in, and purified from, Escherichia coli. The recombinant enzyme is active: the K(m) (470 μM) is higher than the corresponding human enzyme (HsGALE), whereas the k(cat) (2.3 s(-1)) is substantially lower. FhGALE binds NAD(+) and has shown to be dimeric by analytical gel filtration. Like the human and yeast GALEs, FhGALE is stabilized by the substrate UDP-galactose. Molecular modelling predicted that FhGALE adopts a similar overall fold to HsGALE and that tyrosine 155 is likely to be the catalytically critical residue in the active site. In silico screening of the National Cancer Institute Developmental Therapeutics Program library identified 40 potential inhibitors of FhGALE which were tested in vitro. Of these, 6 showed concentration-dependent inhibition of FhGALE, some with nanomolar IC50 values. Two inhibitors (5-fluoroorotate and N-[(benzyloxy)carbonyl]leucyltryptophan) demonstrated selectivity for FhGALE over HsGALE. These compounds also thermally destabilized FhGALE in a concentration-dependent manner. Interestingly, the selectivity of 5-fluoroorotate was not shown by orotic acid, which differs in structure by 1 fluorine atom. These results demonstrate that, despite the structural and biochemical similarities of FhGALE and HsGALE, it is possible to discover compounds which preferentially inhibit FhGALE.

  3. Preliminary estimates of economic impact of liver fluke infection in Thailand and the feasibility of irradiation as a control measure.

    PubMed

    Loaharanu, P; Sornmani, S

    1991-12-01

    Liver fluke infection by Opisthorchis viverrini is the leading cause of food-borne parasitic disease in Thailand. Approximately one third of the population in the northeastern region of the country, ie, 6-7 million, are infected by this parasite through the habit of consuming raw or insufficiently cooked freshwater fish, especially those of cyprinoid family. A recent survey showed that 60% of the work force in the Northeast between the age of 15 and 60 is infected. The estimated wage loss of this population may be approximately Baht 1,620 million (US$65 million) per annum. The estimated direct cost of medical care may be as high as Baht 495 million (US$19.4 million) per annum. Thus, the total direct cost of the infected work force is estimated to be Baht 2115 million (US$84.6 million) per annum. Irradiation of fish flesh infected by metacercaria of O. viverrini has been demonstrated as an effective method of control. A minimum dose of 0.1 kGy is effective without changing physiochemical properties of the fish flesh. This technology, therefore, shows promise as a method to control infection by O. viverrini acquired by the habit of consuming raw freshwater fish in the country. Preliminary economic analyses indicate that the public health benefit from preventing infection with this parasite could outweigh the investment cost of irradiation facilities. Detailed economic feasibility studies should be carried out to demonstrate the practical efficacy and cost-effectiveness of the treatment as a public health intervention measure in the country.

  4. Sequences and gene organization of the mitochondrial genomes of the liver flukes Opisthorchis viverrini and Clonorchis sinensis (Trematoda).

    PubMed

    Cai, X Q; Liu, G H; Song, H Q; Wu, C Y; Zou, F C; Yan, H K; Yuan, Z G; Lin, R Q; Zhu, X Q

    2012-01-01

    Opisthorchis viverrini and Clonorchis sinensis are important trematodes infecting humans and animals, belonging to the family Opisthorchiidae. In the present study, we sequenced the nearly complete mitochondrial (mt) DNA (mtDNA) sequences of O. viverrini from Laos, obtained the complete mtDNA sequences of C. sinensis from China and Korea, and revealed their gene annotations and genome organizations. The mtDNA sequences of O. viverrini, C. sinensis (China isolate), C. sinensis (Korea isolate) were 13,510, 13,879, and 13,877 bp in size, respectively. Each of the three mt genomes comprises 36 genes, consisting of 12 genes coding for proteins, two genes for rRNA, and 20 genes (O. viverrini) or 22 genes (C. sinensis) for tRNA. The gene content and arrangement are identical to that of Fasciola hepatica, and Paragonimus westermani, but distinct from Schistosoma spp. All genes are transcribed in the same direction and have a nucleotide composition high in T. The contents of A + T of the mt genomes were 59.39% for O. viverrini, 60.03% for C. sinensis (China isolate), and 59.99% for C. sinensis (Korea isolate). Phylogenetic analyses using concatenated amino acid sequences of the 12 protein-coding genes, with three different computational algorithms [maximum parsimony, maximum likelihood, and Bayesian analysis], all revealed distinct groups with high statistical support, indicating that O. viverrini and C. sinensis represent sister taxa. These data provide additional novel mtDNA markers for studying the molecular epidemiology and population genetics of the two liver flukes and should have implications for the molecular diagnosis, prevention, and control of opisthorchiasis and clonorchiasis in humans and animals.

  5. Overweight Relation to Liver Fluke Infection among Rural Participants from 4 Districts of Nakhon Ratchasima Province, Thailand.

    PubMed

    Kaewpitoon, Soraya J; Rujirakul, Ratana; Wakkuwattapong, Parichart; Matrakool, Likit; Tongtawee, Taweesak; Panpimanmas, Sukij; Kujapun, Jirawoot; Norkaew, Jun; Photipim, Mali; Ponphimai, Sukanya; Chavengkun, Wassugree; Kompor, Pontip; Padchasuwan, Natnapa; Sawaspol, Sudaporn; Phandee, Mattika Chaimeerang; Phandee, Wichan; Phanurak, Wassana; Kaewpitoon, Natthawut

    2016-01-01

    A cross-sectional survey was conducted among 730 participants from 4 rural districts of Nakhon Ratchasima province, Thailand, with a reported high incidence of liver fluke infection. This study was aimed to examine and evaluate the nutritional status in relation to Opisthorchis viverrini infection. Participants were purposive selected from Chum Phuang, Mueang Yang, Bua Yai, and Kaeng Sanam Nang districts. Stool samples were prepared by Kato Katz technique and then assessed by microscopy. Anthropometry was evaluated according to the body mass index from weight and height. Descriptive statistics and Spearman rank correlation coefficients were used to evaluate the association between the nutritional status and O. viverrini infection. Of 1.64% infected with O. viverrini the highest proportions were found in age groups ≥61 and 41-50 years old, Mueang Yang district. The majorities of participants had normal weight (32.2%), followed by class II obesity (28.1%), class I obesity (21.8%), underweight (10.3%), and class III obesity (8.63%). Nutritional status with class II obesity (rS=0.639, <0.01) and class I obesity (rS=0.582, <0.05), had moderately statistical significant correlations with O. viverrini infection. Meanwhile, normal weight (rS=0.437, <0.05) and class III obesity (rS=0.384, <0.05) demonstrated lower statistical significance. These findings raise the possibility that infection with O. viverrini may contribute to fat deposition and thereby have long-term consequences on human health. Further studies are needed to better understand whether O. viverrini contributes directly to fat deposition and possible mechanisms.

  6. Biochemical Characterization and Differential Expression of a 16.5-Kilodalton Tegument-Associated Antigen from the Liver Fluke Fasciola hepatica

    PubMed Central

    Gaudier, José F.; Cabán-Hernández, Kimberly; Osuna, Antonio

    2012-01-01

    A cDNA encoding a 16.5-kDa protein termed FhTP16.5 was identified by immunoscreening of a cDNA library from Fasciola hepatica adult flukes using pooled sera from rabbits infected with F. hepatica for 4 weeks. Quantitative reverse transcriptase PCR (qPCR) analysis revealed that FhTP16.5 is not expressed in unembryonated eggs. It is poorly expressed in miracidia and highly expressed at the juvenile and adult stages; however, significant differences were found between the expression levels of FhTP16.5 in juveniles versus adult flukes. Recombinant FhTP16.5 was expressed at high levels in Escherichia coli, purified by affinity chromatography, and used to raise anti-FhTP16.5 polyclonal antibodies in rabbits. Immunoblot analysis using the anti-FhTP16.5 IgG antibody identified FhTP16.5 in crude and tegumental extracts and in excretory-secretory products of F. hepatica. The protein was not detected in crude extracts of Schistosoma mansoni or Schistosoma japonicum. Antibodies to FhTP16.5 were detected in the sera of rabbits at 3 to 12 weeks of F. hepatica infection as well as in the sera of humans with chronic fascioliasis; these findings suggest that FhTP16.5 could be a good antigen for serodiagnosis of fascioliasis. Immunohistochemistry demonstrated that FhTP16.5 localizes to the surface of the tegument of various developmental stages and in parenchymal tissues of the adult fluke. Such specific localization makes FhTP16.5 an attractive target for immunoprophylaxis or chemotherapy. PMID:22278327

  7. [New occurrences of metacercariae of Austrodiplostomum compactum (Lutz, 1928) (Platyhelminthes: Digenea) eye flukes of fish from the Paraná Basin].

    PubMed

    Yamada, Fábio Hideki; Moreira, Luis Henrique De A; Ceschini, Tiago L; Takemoto, Ricardo Massato; Pavanelli, Gilberto Cezar

    2008-01-01

    Austrodiplostomum compactum (Platyhelminthes, Digenea) eye flukes of several species of fishes. The presence of this parasite, in extreme cases, can cause swelling of the eyelids, displacement of the retina, opacity of the crystalline lens and blindness or even death. The present study it registers new occurrences of this metacercariae infecting the eyes of four new hosts of fish, Serrasalmus maculatus collected in the Rosana reservoir in the Paranapanema river and Hypostomus regani, Schizodon borellii and Auchenipterus osteomystax collected in the the Upper Paraná River floodplain.

  8. Combined effects of social stress and liver fluke infection in a mouse model.

    PubMed

    Avgustinovich, Damira F; Marenina, Mariya K; Zhanaeva, Svetlana Ya; Tenditnik, Mikhail V; Katokhin, Alexey V; Pavlov, Konstantin S; Sivkov, Anton Yu; Vishnivetskaya, Galina B; Lvova, Maria N; Tolstikova, Tatiana G; Mordvinov, Viatcheslav A

    2016-03-01

    The effects of two influences, social stress and acute opisthorchiasis, were investigated in inbred C57BL/6J male mice. In the model of social stress, mice were repeatedly attacked and defeated by aggressive outbred ICR male mice and were in continuous sensory contact with an aggressive conspecific mouse in their home cage for 20 days. Acute opisthorchiasis was provoked by invasion of Opisthorchis felineus (50 larvae per animal) on the fourth day after the social stress was induced. Simultaneous action of both factors caused the hypertrophy of adrenal glands, as well as elevated the activity of cathepsins B and L in the spleen. This effect on the activity of the cysteine proteases in the hippocampus and hypothalamus following O. felineus invasion was the predominant result of simultaneous action with social stress. Acute opisthorchiasis, social stress, and their combination caused an increase in the level of blood IL-6 in approximately 30% of the animals. Social stress induced a more pronounced effect on mouse plus-maze behavior than O. felineus invasion. Our results suggest a more severe negative effect of the simultaneous influence of both factors on most of the parameters that were investigated. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Child Exploitation: Some Pieces of the Puzzle.

    ERIC Educational Resources Information Center

    Rohlader, Dorothy

    The report addresses the status in North Carolina and in the nation of child exploitation. Legislative and judicial backgrounds of child pornography and child prostitution are reviewed, and difficulties in obtaining statistical data are noted. Law enforcement issues in pornography are cited, and suggestions for further legislation regarding child…

  10. Exploiting a natural auxotrophy for genetic selection.

    PubMed

    Ramage, Elizabeth; Gallagher, Larry; Manoil, Colin

    2012-08-01

    We exploited the natural histidine auxotrophy of Francisella species to develop hisD (encodes histidinol dehydrogenase) as a positive selection marker. A shuttle plasmid (pBR103) carrying Escherichia coli hisD and designed for cloning of PCR fragments replicated in both attenuated and highly virulent Francisella strains. During this work, we formulated a simplified defined growth medium for Francisella novicida.

  11. User interface development for semiautomated imagery exploitation

    NASA Astrophysics Data System (ADS)

    O'Connor, R. P.; Bohling, Edward H.

    1991-08-01

    Operational reconnaissance technical organizations are burdened by greatly increasing workloads due to expanding capabilities for collection and delivery of large-volume near-real- time multisensor/multispectral softcopy imagery. Related to the tasking of reconnaissance platforms to provide the imagery are more stringent timelines for exploiting the imagery in response to the rapidly changing threat environment being monitored. The development of a semi-automated softcopy multisensor image exploitation capability is a critical step toward integrating existing advanced image processing techniques in conjunction with appropriate intelligence and cartographic data for next-generation image exploitation systems. This paper discusses the results of a recent effort to develop computer-assisted aids for the image analyst (IA) in order to rapidly and accurately exploit multispectral/multisensor imagery in combination with intelligence support data and cartographic information for the purpose of target detection and identification. A key challenge of the effort was to design and implement an effective human-computer interface that would satisfy any generic IA task and readily accommodate the needs of a broad range of IAs.

  12. Child Exploitation: Some Pieces of the Puzzle.

    ERIC Educational Resources Information Center

    Rohlader, Dorothy

    The report addresses the status in North Carolina and in the nation of child exploitation. Legislative and judicial backgrounds of child pornography and child prostitution are reviewed, and difficulties in obtaining statistical data are noted. Law enforcement issues in pornography are cited, and suggestions for further legislation regarding child…

  13. Geothermal energy exploitation in New Zealand

    SciTech Connect

    Elder, J.W.

    1980-01-01

    The essential factors, human and technical, which control the operation of geothermal systems, particularly those which allow prediction of behavior during and after exploitation, are sketched. The strategy and co-ordination involved in using New Zealand's geothermal resources for power production are considered. The broader aspects of the technical matters involved in the design of the parasitic plant reservoir system are described. (MHR)

  14. Trolling may intensify exploitation in crappie fisheries

    USGS Publications Warehouse

    Meals, K. O.; Dunn, A. W.; Miranda, Leandro E.

    2012-01-01

    In some parts of the USA, anglers targeting crappies Pomoxis spp. are transitioning from mostly stationary angling with a single pole around submerged structures to using multiple poles while drifting with the wind or under power. This shift in fishing methods could result in a change in catch efficiency, possibly increasing exploitation rates to levels that would be of concern to managers. We studied the catch statistics of anglers fishing while trolling with multiple poles (trollers) and those fishing with single poles (polers) in Mississippi reservoirs. Specifically, we tested whether (1) various catch statistics differed between trollers and polers, (2) catch rates of trollers were related to the number of poles fished, and (3) trollers could raise exploitation rates to potentially unsustainable levels. Results showed that participation in the crappie fisheries was about equally split between polers and trollers. In spring, 90% of crappie anglers were polers; in summer, 85% of crappie anglers were trollers. The size of harvested crappies was similar for the two angler groups, but the catch per hour was almost three times higher for trollers than for polers. Catch rates by trollers were directly correlated to the number of poles fished, although the relationship flattened as the number of poles increased. The average harvest rate for one troller fishing with three poles was similar to the harvest rate obtained by one poler. Simulations predicted that at the existing mix of about 50% polers and 50% trollers and with no restrictions on the number of poles used by trollers, exploitation of crappies is about 1.3 times higher than that in a polers-only fishery; under a scenario in which 100% of crappie anglers were trollers, exploitation was forecasted to increase to about 1.7 times the polers-only rate. The efficiency of trolling for crappies should be of concern to fishery managers because crappie fisheries are mostly consumptive and may increase exploitation

  15. Dissemination and Exploitation: Project Goals beyond Science

    NASA Astrophysics Data System (ADS)

    Hamann, Kristin; Reitz, Anja

    2017-04-01

    Dissemination and Exploitation are essential parts of public funded projects. In Horizon 2020 a plan for the exploitation and dissemination of results (PEDR) is a requirement. The plan should contain a clear vision on the objectives of the project in relation to actions for dissemination and potential exploitation of the project results. The actions follow the basic idea to spread the knowledge and results gathered within the project and face the challenge of how to bring the results into potentially relevant policy circle and how they impact the market. The plan follows the purpose to assess the impact of the project and to address various target groups who are interested in the project results. Simply put, dissemination concentrates on the transfer of knowledge and exploitation on the commercialization of the project. Beyond the question of the measurability of project`s impact, strategies within science marketing can serve purposes beyond internal and external communication. Accordingly, project managers are facing the challenge to implement a dissemination and exploitation strategy that ideally supports the identification of all partners with the project and matches the current discourse of the project`s content within the society, politics and economy. A consolidated plan might unite all projects partners under a central idea and supports the identification with the project beyond the individual research questions. Which applications, strategies and methods can be used to bring forward a PEDR that accompanies a project successfully and allows a comprehensive assessment of the project afterwards? Which hurdles might project managers experience in the dissemination process and which tasks should be fulfilled by the project manager?

  16. Blood Disorders

    MedlinePlus

    ... blood cells, white blood cells and platelets. Blood disorders affect one or more parts of the blood ... They can be acute or chronic. Many blood disorders are inherited. Other causes include other diseases, side ...

  17. Blood pressure

    MedlinePlus Videos and Cool Tools

    Normal blood pressure is important for proper blood flow to the body's organs and tissues. The force of the blood on the walls of the arteries is called blood pressure. Blood pressure is measured both as the heart ...

  18. Blood Disorders

    MedlinePlus

    ... Blood Clots) Blood clot in a deep vein. Hemophilia Blood does not clot properly. Hereditary Hemorrhagic Telangiectasia ( ... infants. Blood Disorders Homepage Venous Thromboembolism (Blood Clots) Hemophilia Hereditary Hemorrhagic Telangiectasia (HHT) Sickle Cell Disease Thalassemia ...

  19. Salmonella Typhimurium exploits inflammation to its own advantage in piglets

    PubMed Central

    Chirullo, Barbara; Pesciaroli, Michele; Drumo, Rosanna; Ruggeri, Jessica; Razzuoli, Elisabetta; Pistoia, Claudia; Petrucci, Paola; Martinelli, Nicola; Cucco, Lucilla; Moscati, Livia; Amadori, Massimo; Magistrali, Chiara F.; Alborali, Giovanni L.; Pasquali, Paolo

    2015-01-01

    Salmonella Typhimurium (S. Typhimurium) is responsible for foodborne zoonotic infections that, in humans, induce self-limiting gastroenteritis. The aim of this study was to evaluate whether the wild-type strain S. Typhimurium (STM14028) is able to exploit inflammation fostering an active infection. Due to the similarity between human and porcine diseases induced by S. Typhimurium, we used piglets as a model for salmonellosis and gastrointestinal research. This study showed that STM14028 is able to efficiently colonize in vitro porcine mono-macrophages and intestinal columnar epithelial (IPEC-J2) cells, and that the colonization significantly increases with LPS pre-treatment. This increase was then reversed by inhibiting the LPS stimulation through LPS antagonist, confirming an active role of LPS stimulation in STM14028-intracellular colonization. Moreover, LPS in vivo treatment increased cytokines blood level and body temperature at 4 h post infection, which is consistent with an acute inflammatory stimulus, capable to influence the colonization of STM14028 in different organs and tissues. The present study proves for the first time that in acute enteric salmonellosis, S. Typhimurium exploits inflammation for its benefit in piglets. PMID:26441914

  20. The origin of the giant liver fluke, Fascioloides magna (Trematoda: Fasciolidae) from Croatia determined by high-resolution melting screening of mitochondrial cox1 haplotypes.

    PubMed

    Bazsalovicsová, Eva; Králová-Hromadová, Ivica; Radvánszky, Ján; Beck, Relja

    2013-07-01

    The high-resolution melting (HRM) method, recently optimized as a reliable technique for population study of the European Fascioloides magna populations, was applied to determine an origin of F. magna individuals from Croatia. The structure and frequency of mitochondrial cytochrome c oxidase subunit I (439 bp; cox1) haplotypes of 200 Croatian flukes coming from 19 red deer (Cervus elaphus elaphus) livers were screened and compared with recently determined reference samples of F. magna from all European foci-Italy, Czech Republic, and Danube floodplain forests. While the reference haplotypes Ha1 and Ha2 were specific for flukes from the first European focus of fascioloidosis, the Natural Park La Mandria in Italy, the remaining three haplotypes (Ha3, Ha4, and Ha5) represented parasites from the second focus, Czech Republic. Besides, Ha3 and Ha4 were found also in the third, latest, and still expanding European focus, the Danube floodplain forests. The HRM screening of cox1 haplotypes of Croatian F. magna individuals resulted in classification of samples into the two mitochondrial haplogroups characterized by well-distinguished melting curves. They corresponded to Ha3 and Ha4 reference haplotypes that confirmed the Danube origin of F. magna from Croatia. The results support the theory that the Danube floodplain forests population of F. magna represents uniform genetic pool of the parasite. The spread of F. magna alongside the Danube River down to Croatia was possible due to suitable ecological conditions for definitive and intermediate hosts present in this unique biotope.

  1. The role of hepatic myofibroblasts in liver cirrhosis in fallow deer (Dama dama) naturally infected with giant liver fluke (Fascioloides magna).

    PubMed

    Marinković, Darko; Kukolj, Vladimir; Aleksić-Kovačević, Sanja; Jovanović, Milijan; Knežević, Milijana

    2013-03-06

    This paper describes liver cirrhosis in 35 fallow deer infected with the giant liver fluke, as well as the distribution, origin, and role of myofibroblasts in its development. In liver of infected deer, stripes of connective tissue are wound around groups of degenerated and regenerated liver lobuli. In the connective tissue, lymphocytes and macrophages which often contain parasite hematin are also present. The walls of the bile ducts are thickened, the epithelium multiplied with mucous metaplasia, and desquamated cells, parasite eggs and brown pigment are present in their lumen.In the livers with cirrhosis, immunopositivity to α-SMA and desmin was observed in cells in portal and septal spaces, at the edge between fibrotic septa and the surrounding parenchyma and in perisinusoidal spaces. These cells vary in size, they are round, oval, spindle-shaped or irregular in shape, similar to vascular smooth muscle cells. The derangement of epithelial-mesenchymal interactions detected in chronic cholangiopathies is most probably the pro-fibrogenic mechanism in liver cirrhosis of fallow deer (Dama dama) infected with the giant liver fluke (Fascioloides magna). Myofibroblasts, especially hepatic stellate cells (HSCs), play an important role in the synthesis of extracellular matrix components in the development of parasitic fibrosis and cirrhosis in the liver of fallow deer.

  2. High prevalence of the liver fluke Amphimerus sp. in domestic cats and dogs in an area for human amphimeriasis in Ecuador.

    PubMed

    Calvopiña, Manuel; Cevallos, William; Atherton, Richard; Saunders, Matthew; Small, Alexander; Kumazawa, Hideo; Sugiyama, Hiromu

    2015-02-01

    Amphimerus sp. is a liver fluke which recently has been shown to have a high prevalence of infection among an indigenous group, Chachi, who reside in a tropical rainforest in the northwestern region of Ecuador. Since it is unknown which animals can act as a reservoir and/or definitive hosts for Amphimerus sp. in this endemic area, a study was done to determine the prevalence of infection in domestic cats and dogs. This information is important to understand the epidemiology, life cycle and control of this parasite. In July 2012, three Chachi communities located on Rio Cayapas, province of Esmeraldas, were surveyed. A total of 89 of the 109 registered households participated in the study. Of the 27 cats and 43 dogs found residing in the communities, stool samples were collected from 14 cats and 31 dogs (total of 45 animals) and examined microscopically for the presence of Amphimerus eggs. The prevalence of infection was 71.4% in cats and 38.7% in dogs, with similar rates of infection in all three communities. Significantly more cats were infected than dogs (p = 0.042). The data show a high rate of Amphimerus sp. infection in domestic cats and dogs residing in Chachi communities. It can be concluded that these animals act as definitive and reservoir hosts for this liver fluke and that amphimeriasis is a zoonotic disease. These findings provide important epidemiological data which will aid in the development and implementation of control strategies against the transmission of Amphimerus.

  3. Immunization and challenge shown by hamsters infected with Opisthorchis viverrini following exposure to gamma-irradiated metacercariae of this carcinogenic liver fluke

    PubMed Central

    Papatpremsiri, A.; Junpue, P.; Loukas, A.; Brindley, P.J.; Bethony, J.M.; Sripa, B.; Laha, T.

    2016-01-01

    Here we report findings to optimize and standardize conditions to attenuate metacercariae of Opisthorchis viverrini by ionizing radiation to elicit protective immune responses to challenge infection. Metacercariae were gamma-irradiated and the ability of irradiated metacercariae to prevent patent infection of challenge metacercariae in hamsters was determined, as well as their ability to induce a host antibody response. Metacercariae irradiated in a dose-dependent manner, with 3, 5, 10, 12, 20, 25 and 50 Gray, were used to infect Syrian golden hamsters by stomach gavage to ascertain the effect of irradiation on ability of the worms to establish infection. In addition, other hamsters were infected with metacercariae irradiated with 20–50 Gray, followed by challenge with intact/wild-type (non-irradiated) metacercariae to determine the protective effect as established by the numbers of adult flukes, eggs of O. viverrini in hamster faeces and anti-O. viverrini antibody titres. Significantly fewer worms were recovered from hamsters immunized with metacercariae irradiated at 20, 25 and 50 Gray than from control hamsters infected with intact metacercariae or 0 Gray, and the worms showed damaged reproductive organs. Faecal egg numbers were decreased significantly in hamsters immunized with 25 and 50 Gray metacercariae of O. viverrini. Moreover, hamsters administered metacercariae that were protected elicited a robust, specific anti-fluke immunoglobulin G response compared to control hamsters, suggesting a role for antibody in protection elicited by radiation-attenuated metacercariae. PMID:25315797

  4. Liver Fluke Infection and Fish Consumption in Khon Kaen, Thailand: A Case Study on Negotiating the Middle Ground between Western Science and Eastern Culture

    NASA Astrophysics Data System (ADS)

    Samiphak, Sara

    This research investigates why typical strategies for promoting health, prolonging life, and preventing disease do not work in many communities. I use the liver fluke infection endemic in Khon Kaen, Thailand to explore the middle ground between Western science and Eastern culture. Prior work on the O.viverrini infection in Khon Kaen, Thailand has focused almost exclusively on developing effective medical treatment for the liver fluke infection. This dissertation employs a case study designed to explore the conditions that created and perpetuate the problem in the first place. In concrete terms, I analyze how the worldviews of local villagers shape their attitudes toward life (and death), which in turn determine if they engage in the high-risk behavior -- eating undercooked fish -- that makes them vulnerable to the infection. My research focuses on these people in-situ over a three-month period, and includes data from participant-observation, interviews, and video-recordings. This work seeks to illuminate how people's thinking and reasoning skills, and personal/cultural identities affect their abilities to learn and act on new health concepts. This potentially provides a window into future educational strategies in a complex world.

  5. Immunization and challenge shown by hamsters infected with Opisthorchis viverrini following exposure to gamma-irradiated metacercariae of this carcinogenic liver fluke.

    PubMed

    Papatpremsiri, A; Junpue, P; Loukas, A; Brindley, P J; Bethony, J M; Sripa, B; Laha, T

    2016-01-01

    Here we report findings to optimize and standardize conditions to attenuate metacercariae of Opisthorchis viverrini by ionizing radiation to elicit protective immune responses to challenge infection. Metacercariae were gamma-irradiated and the ability of irradiated metacercariae to prevent patent infection of challenge metacercariae in hamsters was determined, as well as their ability to induce a host antibody response. Metacercariae irradiated in a dose-dependent manner, with 3, 5, 10, 12, 20, 25 and 50 Gray, were used to infect Syrian golden hamsters by stomach gavage to ascertain the effect of irradiation on ability of the worms to establish infection. In addition, other hamsters were infected with metacercariae irradiated with 20-50 Gray, followed by challenge with intact/wild-type (non-irradiated) metacercariae to determine the protective effect as established by the numbers of adult flukes, eggs of O. viverrini in hamster faeces and anti-O. viverrini antibody titres. Significantly fewer worms were recovered from hamsters immunized with metacercariae irradiated at 20, 25 and 50 Gray than from control hamsters infected with intact metacercariae or 0 Gray, and the worms showed damaged reproductive organs. Faecal egg numbers were decreased significantly in hamsters immunized with 25 and 50 Gray metacercariae of O. viverrini. Moreover, hamsters administered metacercariae that were protected elicited a robust, specific anti-fluke immunoglobulin G response compared to control hamsters, suggesting a role for antibody in protection elicited by radiation-attenuated metacercariae.

  6. Intelligence, mapping, and geospatial exploitation system (IMAGES)

    NASA Astrophysics Data System (ADS)

    Moellman, Dennis E.; Cain, Joel M.

    1998-08-01

    This paper provides further detail to one facet of the battlespace visualization concept described in last year's paper Battlespace Situation Awareness for Force XXI. It focuses on the National Imagery and Mapping Agency (NIMA) goal to 'provide customers seamless access to tailorable imagery, imagery intelligence, and geospatial information.' This paper describes Intelligence, Mapping, and Geospatial Exploitation System (IMAGES), an exploitation element capable of CONUS baseplant operations or field deployment to provide NIMA geospatial information collaboratively into a reconnaissance, surveillance, and target acquisition (RSTA) environment through the United States Imagery and Geospatial Information System (USIGS). In a baseplant CONUS setting IMAGES could be used to produce foundation data to support mission planning. In the field it could be directly associated with a tactical sensor receiver or ground station (e.g. UAV or UGV) to provide near real-time and mission specific RSTA to support mission execution. This paper provides IMAGES functional level design; describes the technologies, their interactions and interdependencies; and presents a notional operational scenario to illustrate the system flexibility. Using as a system backbone an intelligent software agent technology, called Open Agent ArchitectureTM (OAATM), IMAGES combines multimodal data entry, natural language understanding, and perceptual and evidential reasoning for system management. Configured to be DII COE compliant, it would utilize, to the extent possible, COTS applications software for data management, processing, fusion, exploitation, and reporting. It would also be modular, scaleable, and reconfigurable. This paper describes how the OAATM achieves data synchronization and enables the necessary level of information to be rapidly available to various command echelons for making informed decisions. The reasoning component will provide for the best information to be developed in the timeline

  7. Fluke egg characteristics for the diagnosis of human and animal fascioliasis by Fasciola hepatica and F. gigantica.

    PubMed

    Valero, M Adela; Perez-Crespo, Ignacio; Periago, M Victoria; Khoubbane, Messaoud; Mas-Coma, Santiago

    2009-08-01

    In trematodiases, shape and size of the fluke eggs shed with faeces are crucial diagnostic features because of their typically reduced intraspecific variability. In fascioliasis, the usual diagnosis during the biliary stage of infection is based on the classification of eggs found in stools, duodenal contents or bile. The aim of the present study is to validate the identification of Fasciola species based on the shape and size of eggs shed by humans, characterizing their morphometric traits using a computer image analysis system (CIAS). The influence of both the geographical location and of the host (human and livestock) has been analysed. Coprological studies were carried out in fascioliasis human endemic areas, where only F. hepatica is present (the northern Bolivian Altiplano and the Cajamarca valley in Peru), and where F. hepatica and F. gigantica coexist (the Kutaisi region of Georgia, the Nile Delta in Egypt, and the Quy Nhon province in Vietnam). Classically, it is considered that at the abopercular end of the shell of Fasciola eggs there is often a roughened or irregular area. Nevertheless, results show that the frequency of the presence of this feature in F. hepatica is population-dependent, and therefore is not a pathognomonic criterion in diagnosis. The study reveals that eggs shed by humans show morphological traits different from eggs shed by animals. In humans, F. hepatica eggs are bigger and F. gigantica eggs are smaller than reported to date from livestock, and their measurements overlap when compared. The material analysed in this study shows that the size of eggs shed by humans from Georgia and Egypt corresponds to the F. hepatica morph, while the size of eggs shed by humans from Vietnam corresponds to the F. gigantica morph. Measurements of F. hepatica and F. gigantica eggs originating from humans and animals from sympatric areas overlap, and, therefore, they do not allow differential diagnosis when within this overlapping range. In this sense

  8. Exploiting host immunity: the Salmonella paradigm

    PubMed Central

    Behnsen, Judith; Perez-Lopez, Araceli; Nuccio, Sean-Paul; Raffatellu, Manuela

    2014-01-01

    Pathogens have evolved clever strategies to evade and in some cases exploit the attacks of an activated immune system. Salmonella enterica is one such pathogen, exploiting multiple aspects of host defense to promote its replication in the host. Here we review recent findings on the mechanisms by which Salmonella establishes systemic and chronic infection, including strategies involving manipulation of innate immune signaling and inflammatory forms of cell death, as well as immune evasion by establishing residency in M2 macrophages. We also examine recent evidence showing that the oxidative environment and the high levels of antimicrobial proteins produced in response to localized Salmonella gastrointestinal infection enable the pathogen to successfully outcompete the resident gut microbiota. PMID:25582038

  9. Exploiting Non-Markovianity for Quantum Control

    NASA Astrophysics Data System (ADS)

    Reich, Daniel M.; Katz, Nadav; Koch, Christiane P.

    2015-07-01

    Quantum technology, exploiting entanglement and the wave nature of matter, relies on the ability to accurately control quantum systems. Quantum control is often compromised by the interaction of the system with its environment since this causes loss of amplitude and phase. However, when the dynamics of the open quantum system is non-Markovian, amplitude and phase flow not only from the system into the environment but also back. Interaction with the environment is then not necessarily detrimental. We show that the back-flow of amplitude and phase can be exploited to carry out quantum control tasks that could not be realized if the system was isolated. The control is facilitated by a few strongly coupled, sufficiently isolated environmental modes. Our paradigmatic example considers a weakly anharmonic ladder with resonant amplitude control only, restricting realizable operations to SO(N). The coupling to the environment, when harnessed with optimization techniques, allows for full SU(N) controllability.

  10. Exploiting Quantum Resonance to Solve Combinatorial Problems

    NASA Technical Reports Server (NTRS)

    Zak, Michail; Fijany, Amir

    2006-01-01

    Quantum resonance would be exploited in a proposed quantum-computing approach to the solution of combinatorial optimization problems. In quantum computing in general, one takes advantage of the fact that an algorithm cannot be decoupled from the physical effects available to implement it. Prior approaches to quantum computing have involved exploitation of only a subset of known quantum physical effects, notably including parallelism and entanglement, but not including resonance. In the proposed approach, one would utilize the combinatorial properties of tensor-product decomposability of unitary evolution of many-particle quantum systems for physically simulating solutions to NP-complete problems (a class of problems that are intractable with respect to classical methods of computation). In this approach, reinforcement and selection of a desired solution would be executed by means of quantum resonance. Classes of NP-complete problems that are important in practice and could be solved by the proposed approach include planning, scheduling, search, and optimal design.

  11. Tribal children are most exploited - UNICEF.

    PubMed

    A workshop sponsored by the UN Children's Fund in the Philippines examined the status of the children of indigenous people and found that exploitation of the assets of indigenous people in the name of development has resulted in social inequalities that have damaged the indigenous children. As examples of the disregard for the human rights of the children, participants cited projects in Davao, Boracay, and Benguet that have displaced native children. These include mining schemes that have "raped" ancestral lands, large-scale agricultural enterprises, promotion of tourism, and creation of hydroelectric dams. The children rarely benefit at all from any of these projects as their families are moved from a position of isolated independence to one of exploited dependence. Social changes accompanying development ruin traditional culture without providing a better or even similar basis of existence.

  12. Exploiting Virtual Synchrony in Distributed Systems

    DTIC Science & Technology

    1987-02-01

    state, by having each current member reply with a data structure encoding this information. In a virtually syn- chronous sense , the new member joins...Exlitn Virua Sychon inf :en.et P. Birma ThmbA.Jsp TECHNICAL REPORTF Department of Computer Science Cornell University Ithaca, New York Exploiting...1 Department of Computer Science Justifi: i ____ Cornell University Ithaca, New York 14853-7501 Distrit ui. _w/ - Avail * t ] ’ - Dist S;. This work

  13. Macropinocytosis Exploitation by Cancers and Cancer Therapeutics

    PubMed Central

    Ha, Kevin D.; Bidlingmaier, Scott M.; Liu, Bin

    2016-01-01

    Macropinocytosis has long been known as a primary method for cellular intake of fluid-phase and membrane-bound bulk cargo. This review seeks to re-examine the latest studies to emphasize how cancers exploit macropinocytosis to further their tumorigenesis, including details in how macropinocytosis can be adapted to serve diverse functions. Furthermore, this review will also cover the latest endeavors in targeting macropinocytosis as an avenue for novel therapeutics. PMID:27672367

  14. DANDRUFF: THE MOST COMMERCIALLY EXPLOITED SKIN DISEASE

    PubMed Central

    Ranganathan, S; Mukhopadhyay, T

    2010-01-01

    The article discuss in detail about the prevalence, pathophysiology, clinical manifestations of dandruff including the etio-pathology. The article also discusses in detail about various treatment methods available for dandruff. The status of dandruff being amphibious – a disease/disorder, and relatively less medical intervention is sought after for the treatment, dandruff is the most commercially exploited skin and scalp disorder/disease by personal care industries. PMID:20606879

  15. SAIM: a mobile multisensor image exploitation system

    NASA Astrophysics Data System (ADS)

    Devambez, Francois

    2000-11-01

    The control of information is an essential part of operations. Technology allows today a near real time surveillance capacity, over wide areas, due to sensor performances, communication networks. The system presented herein has been developed by Thomson-Csf, under contract with the French MOD to give to the decision makers the right information, in a very short delay, and prepare support information, to help for decision. The SAIM, Mobile Multisensor Image Exploitation Ground System, uses near real time acquisition units, very large data base management, data processing, including fusion and decision aiding tools, and communication networks. It then helps for all the steps of exploitation of data incoming from image sensors, form preparation of the reconnaissance mission to the dissemination of intelligence. The SAIM system is in operations in the French Air Force, and soon in the French Navy and the French Army. Initially defined for the specific use of French Recce sensors, the SAIM is now intended to be widely used for the exploitation of UAV and battle field MTI and SAR surveillance systems.

  16. Blood clotting

    MedlinePlus Videos and Cool Tools

    ... the external bleeding stops. Clotting factors in the blood cause strands of blood-borne material, called fibrin, to stick together and ... the inside of the wound. Eventually, the cut blood vessel heals, and the blood clot dissolves after ...

  17. Blood typing

    MedlinePlus

    A blood sample is needed. The test to determine your blood group is called ABO typing. Your blood sample is mixed with antibodies against type A and B blood. Then, the sample is checked to see whether ...

  18. Blood culture

    MedlinePlus

    Culture - blood ... A blood sample is needed . The site where blood will be drawn is first cleaned with an antiseptic such ... organism from the skin getting into (contaminating) the blood sample and causing a false-positive result (see ...

  19. Blood transfusions

    MedlinePlus

    ... this page: //medlineplus.gov/ency/patientinstructions/000431.htm Blood transfusions To use the sharing features on this ... several sources of blood which are described below. Blood From the Public (Volunteer Blood Donation) The most ...

  20. Blood Types

    MedlinePlus

    ... FIND A BLOOD DRIVE Blood Types and the Population O positive is the most common blood type. ... of the different blood types in the U.S. population is: Caucasian African- American Latino-American Asian O + ...

  1. The mitochondrial genome of Paragonimus westermani (Kerbert, 1878), the Indian isolate of the lung fluke representative of the family Paragonimidae (Trematoda).

    PubMed

    Biswal, Devendra K; Chatterjee, Anupam; Bhattacharya, Alok; Tandon, Veena

    2014-01-01

    Among helminth parasites, Paragonimus (zoonotic lung fluke) gains considerable importance from veterinary and medical points of view because of its diversified effect on its host. Nearly fifty species of Paragonimus have been described across the globe. It is estimated that more than 20 million people are infected worldwide and the best known species is Paragonimus westermani, whose type locality is probably India and which infects millions of people in Asia causing disease symptoms that mimic tuberculosis. Human infections occur through eating raw crustaceans containing metacercarie or ingestion of uncooked meat of paratenic hosts such as pigs. Though the fluke is known to parasitize a wide range of mammalian hosts representing as many as eleven families, the status of its prevalence, host range, pathogenic manifestations and its possible survivors in nature from where the human beings contract the infection is not well documented in India. We took advantage of the whole genome sequence data for P. westermani, generated by Next Generation Sequencing, and its comparison with the existing data for the P. westermani for comparative mt DNA phylogenomic analyses. Specific primers were designed for the 12 protein coding genes with the aid of existing P. westermani mtDNA as the reference. The Ion torrent next generation sequencing platform was harnessed to completely sequence the mitochondrial genome, and applied innovative approaches to bioinformatically assemble and annotate it. A strategic PCR primer design utilizing the whole genome sequence data from P. westermani enabled us to design specific primers capable of amplifying all regions of the mitochondrial genome from P. westermani. Assembly of NGS data from libraries enriched in mtDNA sequence by PCR gave rise to a total of 11 contigs spanning the entire 14.7 kb mt DNA sequence of P. westermani available at NCBI. We conducted gap-filling by traditional Sanger sequencing to fill in the gaps. Annotation of non

  2. The mitochondrial genome of Paragonimus westermani (Kerbert, 1878), the Indian isolate of the lung fluke representative of the family Paragonimidae (Trematoda)

    PubMed Central

    Biswal, Devendra K.; Chatterjee, Anupam

    2014-01-01

    Among helminth parasites, Paragonimus (zoonotic lung fluke) gains considerable importance from veterinary and medical points of view because of its diversified effect on its host. Nearly fifty species of Paragonimus have been described across the globe. It is estimated that more than 20 million people are infected worldwide and the best known species is Paragonimus westermani, whose type locality is probably India and which infects millions of people in Asia causing disease symptoms that mimic tuberculosis. Human infections occur through eating raw crustaceans containing metacercarie or ingestion of uncooked meat of paratenic hosts such as pigs. Though the fluke is known to parasitize a wide range of mammalian hosts representing as many as eleven families, the status of its prevalence, host range, pathogenic manifestations and its possible survivors in nature from where the human beings contract the infection is not well documented in India. We took advantage of the whole genome sequence data for P. westermani, generated by Next Generation Sequencing, and its comparison with the existing data for the P. westermani for comparative mt DNA phylogenomic analyses. Specific primers were designed for the 12 protein coding genes with the aid of existing P. westermani mtDNA as the reference. The Ion torrent next generation sequencing platform was harnessed to completely sequence the mitochondrial genome, and applied innovative approaches to bioinformatically assemble and annotate it. A strategic PCR primer design utilizing the whole genome sequence data from P. westermani enabled us to design specific primers capable of amplifying all regions of the mitochondrial genome from P. westermani. Assembly of NGS data from libraries enriched in mtDNA sequence by PCR gave rise to a total of 11 contigs spanning the entire 14.7 kb mt DNA sequence of P. westermani available at NCBI. We conducted gap-filling by traditional Sanger sequencing to fill in the gaps. Annotation of non

  3. Exploitation of subsea gas hydrate reservoirs

    NASA Astrophysics Data System (ADS)

    Janicki, Georg; Schlüter, Stefan; Hennig, Torsten; Deerberg, Görge

    2016-04-01

    Natural gas hydrates are considered to be a potential energy resource in the future. They occur in permafrost areas as well as in subsea sediments and are stable at high pressure and low temperature conditions. According to estimations the amount of carbon bonded in natural gas hydrates worldwide is two times larger than in all known conventional fossil fuels. Besides technical challenges that have to be overcome climate and safety issues have to be considered before a commercial exploitation of such unconventional reservoirs. The potential of producing natural gas from subsea gas hydrate deposits by various means (e.g. depressurization and/or injection of carbon dioxide) is numerically studied in the frame of the German research project »SUGAR«. The basic mechanisms of gas hydrate formation/dissociation and heat and mass transport in porous media are considered and implemented into a numerical model. The physics of the process leads to strong non-linear couplings between hydraulic fluid flow, hydrate dissociation and formation, hydraulic properties of the sediment, partial pressures and seawater solution of components and the thermal budget of the system described by the heat equation. This paper is intended to provide an overview of the recent development regarding the production of natural gas from subsea gas hydrate reservoirs. It aims at giving a broad insight into natural gas hydrates and covering relevant aspects of the exploitation process. It is focused on the thermodynamic principles and technological approaches for the exploitation. The effects occurring during natural gas production within hydrate filled sediment layers are identified and discussed by means of numerical simulation results. The behaviour of relevant process parameters such as pressure, temperature and phase saturations is described and compared for different strategies. The simulations are complemented by calculations for different safety relevant problems.

  4. Gaze interaction in UAS video exploitation

    NASA Astrophysics Data System (ADS)

    Hild, Jutta; Brüstle, Stefan; Heinze, Norbert; Peinsipp-Byma, Elisabeth

    2013-05-01

    A frequently occurring interaction task in UAS video exploitation is the marking or selection of objects of interest in the video. If an object of interest is visually detected by the image analyst, its selection/marking for further exploitation, documentation and communication with the team is a necessary task. Today object selection is usually performed by mouse interaction. As due to sensor motion all objects in the video move, object selection can be rather challenging, especially if strong and fast and ego-motions are present, e.g., with small airborne sensor platforms. In addition to that, objects of interest are sometimes too shortly visible to be selected by the analyst using mouse interaction. To address this issue we propose an eye tracker as input device for object selection. As the eye tracker continuously provides the gaze position of the analyst on the monitor, it is intuitive to use the gaze position for pointing at an object. The selection is then actuated by pressing a button. We integrated this gaze-based "gaze + key press" object selection into Fraunhofer IOSB's exploitation station ABUL using a Tobii X60 eye tracker and a standard keyboard for the button press. Representing the object selections in a spatial relational database, ABUL enables the image analyst to efficiently query the video data in a post processing step for selected objects of interest with respect to their geographical and other properties. An experimental evaluation is presented, comparing gaze-based interaction with mouse interaction in the context of object selection in UAS videos.

  5. Algorithms exploiting ultrasonic sensors for subject classification

    NASA Astrophysics Data System (ADS)

    Desai, Sachi; Quoraishee, Shafik

    2009-09-01

    Proposed here is a series of techniques exploiting micro-Doppler ultrasonic sensors capable of characterizing various detected mammalian targets based on their physiological movements captured a series of robust features. Employed is a combination of unique and conventional digital signal processing techniques arranged in such a manner they become capable of classifying a series of walkers. These processes for feature extraction develops a robust feature space capable of providing discrimination of various movements generated from bipeds and quadrupeds and further subdivided into large or small. These movements can be exploited to provide specific information of a given signature dividing it in a series of subset signatures exploiting wavelets to generate start/stop times. After viewing a series spectrograms of the signature we are able to see distinct differences and utilizing kurtosis, we generate an envelope detector capable of isolating each of the corresponding step cycles generated during a walk. The walk cycle is defined as one complete sequence of walking/running from the foot pushing off the ground and concluding when returning to the ground. This time information segments the events that are readily seen in the spectrogram but obstructed in the temporal domain into individual walk sequences. This walking sequence is then subsequently translated into a three dimensional waterfall plot defining the expected energy value associated with the motion at particular instance of time and frequency. The value is capable of being repeatable for each particular class and employable to discriminate the events. Highly reliable classification is realized exploiting a classifier trained on a candidate sample space derived from the associated gyrations created by motion from actors of interest. The classifier developed herein provides a capability to classify events as an adult humans, children humans, horses, and dogs at potentially high rates based on the tested sample

  6. Art Therapy Exhibitions: Exploitation or Advocacy?

    PubMed

    Davis, Terri

    2017-01-01

    Promoting awareness of human trafficking by sharing trauma survivors' art and summaries of their life stories suggests ethical complexities that have been typically neglected by bioethicists. Although these survivors voluntarily share the objects they created during art therapy sessions, they are still at risk of harm, including further exploitation, due to their vulnerability, high rates of victim sensitivity, and the mental health consequences of their traumatic experiences. While some argue that the benefits of sublimation and art therapy for human trafficking survivors make sharing their art worth the risk, anti-trafficking organizations and supporters of such art exhibitions have responsibilities to be trauma informed. © 2017 American Medical Association. All Rights Reserved.

  7. Fluke Fairness Act

    THOMAS, 113th Congress

    Rep. Bishop, Timothy H. [D-NY-1

    2014-01-14

    House - 01/16/2014 Referred to the Subcommittee on Fisheries, Wildlife, Oceans, and Insular Affairs. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  8. Competing Discourses about Youth Sexual Exploitation in Canadian News Media.

    PubMed

    Saewyc, Elizabeth M; Miller, Bonnie B; Rivers, Robert; Matthews, Jennifer; Hilario, Carla; Hirakata, Pam

    2013-10-01

    Media holds the power to create, maintain, or break down stigmatizing attitudes, which affect policies, funding, and services. To understand how Canadian news media depicts the commercial sexual exploitation of children and youth, we examined 835 Canadian newspaper articles from 1989-2008 using a mixed methods critical discourse analysis approach, comparing representations to existing research about sexually exploited youth. Despite research evidence that equal rates of boys and girls experience exploitation, Canadian news media depicted exploited youth predominantly as heterosexual girls, and described them alternately as victims or workers in a trade, often both in the same story. News media mentioned exploiters far less often than victims, and portrayed them almost exclusively as male, most often called 'customers' or 'consumers,' and occasionally 'predators'; in contrast, research has documented the majority of sexually exploited boys report female exploiters. Few news stories over the past two decades portrayed the diversity of victims, perpetrators, and venues of exploitation reported in research. The focus on victims but not exploiters helps perpetuate stereotypes of sexual exploitation as business or a 'victimless crime,' maintains the status quo, and blurs responsibility for protecting youth under the UN Convention on the Rights of the Child. Health care providers and researchers can be advocates for accuracy in media coverage about sexual exploitation; news reporters and editors should focus on exploiters more than victims, draw on existing research evidence to avoid perpetuating stereotypes, and use accurate terms, such as commercial sexual exploitation, rather than terms related to business or trade.

  9. Advances in Blood Typing.

    PubMed

    Quraishy, N; Sapatnekar, S

    The clinical importance of blood group antigens relates to their ability to evoke immune antibodies that are capable of causing hemolysis. The most important antigens for safe transfusion are ABO and D (Rh), and typing for these antigens is routinely performed for patients awaiting transfusion, prenatal patients, and blood donors. Typing for other blood group antigens, typically of the Kell, Duffy, Kidd, and MNS blood groups, is sometimes necessary, for patients who have, or are likely to develop antibodies to these antigens. The most commonly used typing method is serological typing, based on hemagglutination reactions against specific antisera. This method is generally reliable and practical for routine use, but it has certain drawbacks. In recent years, molecular typing has emerged as an alternative or supplemental typing method. It is based on detecting the polymorphisms and mutations that control the expression of blood group antigens, and using this information to predict the probable antigen type. Molecular typing methods are useful when traditional serological typing methods cannot be used, as when a patient has been transfused and the sample is contaminated with red blood cells from the transfused blood component. Moreover, molecular typing methods can precisely identify clinically significant variant antigens that cannot be distinguished by serological typing; this capability has been exploited for the resolution of typing discrepancies and shows promise for the improved transfusion management of patients with sickle cell anemia. Despite its advantages, molecular typing has certain limitations, and it should be used in conjunction with serological methods.

  10. Large size space construction for space exploitation

    NASA Astrophysics Data System (ADS)

    Kondyurin, Alexey

    2016-07-01

    Space exploitation is impossible without large space structures. We need to make sufficient large volume of pressurized protecting frames for crew, passengers, space processing equipment, & etc. We have to be unlimited in space. Now the size and mass of space constructions are limited by possibility of a launch vehicle. It limits our future in exploitation of space by humans and in development of space industry. Large-size space construction can be made with using of the curing technology of the fibers-filled composites and a reactionable matrix applied directly in free space. For curing the fabric impregnated with a liquid matrix (prepreg) is prepared in terrestrial conditions and shipped in a container to orbit. In due time the prepreg is unfolded by inflating. After polymerization reaction, the durable construction can be fitted out with air, apparatus and life support systems. Our experimental studies of the curing processes in the simulated free space environment showed that the curing of composite in free space is possible. The large-size space construction can be developed. A project of space station, Moon base, Mars base, mining station, interplanet space ship, telecommunication station, space observatory, space factory, antenna dish, radiation shield, solar sail is proposed and overviewed. The study was supported by Humboldt Foundation, ESA (contract 17083/03/NL/SFe), NASA program of the stratospheric balloons and RFBR grants (05-08-18277, 12-08-00970 and 14-08-96011).

  11. Exploiting Allee effects for managing biological invasions.

    PubMed

    Tobin, Patrick C; Berec, Luděk; Liebhold, Andrew M

    2011-06-01

    Biological invasions are a global and increasing threat to the function and diversity of ecosystems. Allee effects (positive density dependence) have been shown to play an important role in the establishment and spread of non-native species. Although Allee effects can be considered a bane in conservation efforts, they can be a benefit in attempts to manage non-native species. Many biological invaders are subject to some form of an Allee effect, whether due to a need to locate mates, cooperatively feed or reproduce or avoid becoming a meal, yet attempts to highlight the specific exploitation of Allee effects in biological invasions are surprisingly unprecedented. In this review, we highlight current strategies that effectively exploit an Allee effect, and propose novel means by which Allee effects can be manipulated to the detriment of biological invaders. We also illustrate how the concept of Allee effects can be integral in risk assessments and in the prioritization of resources allocated to manage non-native species, as some species beset by strong Allee effects could be less successful as invaders. We describe how tactics that strengthen an existing Allee effect or create new ones could be used to manage biological invasions more effectively.

  12. Exploration versus exploitation in polydomous ant colonies.

    PubMed

    Cook, Zoe; Franks, Daniel W; Robinson, Elva J H

    2013-04-21

    In socially foraging species resource information can be shared between individuals, increasing foraging success. In ant colonies, nestmate recruitment allows high exploitation rates at known resources however, to maximise foraging efficiency this must be balanced with searching for new resources. Many ant species form colonies inhabiting two or more spatially separated but socially connected nests: this type of organisation is known as polydomy. Polydomous colonies may benefit from increased foraging efficiency by carrying out dispersed-central place foraging. However, decentralisation of the colony may affect recruitment success by limiting interaction between ants based in separate nests. We use an agent-based model which compares the foraging success of monodomous and polydomous colonies in different food environments, incorporating recruitment through pheromone trails and group foraging. In contrast to previous results we show that polydomy is beneficial in some but not all cases. Polydomous colonies discover resources at a higher rate, making them more successful when food is highly dispersed, but their relative success can be lowered by limitations on recruitment success. Monodomous colonies can have higher foraging efficiency than polydomous colonies by exploiting food more rapidly. The results show the importance of interactions between recruitment strategy, colony size, and colony organisation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. New stratigraphic technologies in exploration/exploitation

    SciTech Connect

    Scott, R.W.; Lane, H.R.

    1995-09-01

    With the demand for increased accuracy and precision in the interpretation of seismic sections for the prediction of reservoirs and traps, traditional paleontologic and new non-paleontologic stratigraphic data have assumed a greater role in exploration/exploitation. Strata bounded by sequence boundaries can be dated have assumed a greater role in exploration/exploitation. Strata bounded by sequence boundaries can be dated precisely by the graphic correlation technique. For example, Arabian Cretaceous reservoirs pinch out by facies change and diagenesis into coeval strata. But Pliocene sands in the Gulf Coast are truncated by regional unconformities accentuated by salt dome movement. In this Plio-Pleistocene section high precision chronostratigraphy is achieved by the integration of paleontological and geochemical data. Detailed biostratigraphic analysis of many sections of Mississippian carbonates along the eastern side of the Transcontinental Arch allows for the recognition of four unconformity-bounded units (biothems of Lane and others, 1994). These biotherms have been traced form Illinois to New Mexico and are not easily detected in the subsurface by using seismic or electric log technology because of the rather uniform carbonate lithologies composing the entire Mississippian in the region. Mississippian hydrocarbon production in western Kansas can be shown to be associated with these intra-Mississippian carbonate-on-carbonate unconformities that are easily detected biostratigraphically.

  14. Sentinel-1 mission scientific exploitation activities

    NASA Astrophysics Data System (ADS)

    Desnos, Yves louis; Foumelis, Michael; Engdahl, Marcus

    2017-04-01

    The Sentinel-1 mission is the European Imaging Radar Observatory for the Copernicus joint initiative of the European Commission (EC) and the European Space Agency (ESA). Sentinel-1 mission is composed of a constellation of two satellites, Sentinel-1A and Sentinel-1B (launched in April 2014 and April 2016, respectively), sharing the same orbital plane and featuring a short repeat cycle of 6 days optimised for Synthetic Aperture Radar (SAR) interferometry science and applications. The full operation capacity was achieved after the completion of the Sentinel-1B in-orbit commissioning on 14 September 2016. Sentinel-1 data are freely available via the ESA's Sentinels Scientific Data Hub since October 2014. The data uptake by the science community has been unprecedented and numerous results have been published to date. The objective of the current paper is to provide a brief overview of the latest ESA activities, in the frame of the Scientific Exploitation of Operational Missions (SEOM) programme, aimed to facilitate the scientific exploitation of Sentinel-1 mission as well as discuss future opportunities for research.

  15. Compressed sensing MRI exploiting complementary dual decomposition.

    PubMed

    Park, Suhyung; Park, Jaeseok

    2014-04-01

    Compressed sensing (CS) MRI exploits the sparsity of an image in a transform domain to reconstruct the image from incoherently under-sampled k-space data. However, it has been shown that CS suffers particularly from loss of low-contrast image features with increasing reduction factors. To retain image details in such degraded experimental conditions, in this work we introduce a novel CS reconstruction method exploiting feature-based complementary dual decomposition with joint estimation of local scale mixture (LSM) model and images. Images are decomposed into dual block sparse components: total variation for piecewise smooth parts and wavelets for residuals. The LSM model parameters of residuals in the wavelet domain are estimated and then employed as a regional constraint in spatially adaptive reconstruction of high frequency subbands to restore image details missing in piecewise smooth parts. Alternating minimization of the dual image components subject to data consistency is performed to extract image details from residuals and add them back to their complementary counterparts while the LSM model parameters and images are jointly estimated in a sequential fashion. Simulations and experiments demonstrate the superior performance of the proposed method in preserving low-contrast image features even at high reduction factors.

  16. Development and characterization of multiplex panels of polymorphic microsatellite loci in giant liver fluke Fascioloides magna (Trematoda: Fasciolidae), using next-generation sequencing approach.

    PubMed

    Minárik, Gabriel; Bazsalovicsová, Eva; Zvijáková, Ludmila; Stefka, Jan; Pálková, Lenka; Králová-Hromadová, Ivica

    2014-06-01

    The microsatellite markers were designed for the giant liver fluke, Fascioloides magna, veterinary important liver parasite of free-living and domestic ruminants. Due to its geographic distribution (five enzootic regions across USA and Canada, three permanent European foci) and invasive character, F. magna is an interesting model for population genetics. Out of 667 amplicon candidates generated after NGS, 118 provided the best resolution and were tested with PCR analysis. In total, 56 yielded PCR products of expected size and in 36 of them the declared repetitive motif was identified by Sanger sequencing. After fragment analysis, 12 loci were proved to be polymorphic in individuals from one tested European and four North American populations. These loci were selected for setup of multiplex STR assays and utilized in genotyping of larger sample cohort. The outputs of statistical analyses indicate further global application of 11 conclusive loci in population genetics of the parasite. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. The axial musculature of Pontoporia blainvillei, with comments on the organization of this system and its effect on fluke-stroke dynamics in the cetacea.

    PubMed

    Strickler, T L

    1980-01-01

    The axial muscular system of Pontoporia blainvillei is described and compared with published reports of this system in other cetaceans. A comprehensive system for classification of axial muscles is presented, based on the studies of Slijper. A discrete obliquus capitis inferior is described for the first time in cetacea, and it is suggested that its absence in previous descriptions may have been due partly to dissection error. The major axial muscle-masses are organized in a similar way in most cetaceans, comprising a set of tail elevators and depressors, and a set of tendons with similar actions on the flukes. The anatomy of the axial musculature does not support the idea that the upstroke is the main propulsive stroke in cetaceans, but suggests similar roles of the upstroke and downstroke in propulsion.

  18. High Prevalence of the Liver Fluke Amphimerus sp. in Domestic Cats and Dogs in an Area for Human Amphimeriasis in Ecuador

    PubMed Central

    Calvopiña, Manuel; Cevallos, William; Atherton, Richard; Saunders, Matthew; Small, Alexander; Kumazawa, Hideo; Sugiyama, Hiromu

    2015-01-01

    Background Amphimerus sp. is a liver fluke which recently has been shown to have a high prevalence of infection among an indigenous group, Chachi, who reside in a tropical rainforest in the northwestern region of Ecuador. Since it is unknown which animals can act as a reservoir and/or definitive hosts for Amphimerus sp. in this endemic area, a study was done to determine the prevalence of infection in domestic cats and dogs. This information is important to understand the epidemiology, life cycle and control of this parasite. Methodology/Findings In July 2012, three Chachi communities located on Rio Cayapas, province of Esmeraldas, were surveyed. A total of 89 of the 109 registered households participated in the study. Of the 27 cats and 43 dogs found residing in the communities, stool samples were collected from 14 cats and 31 dogs (total of 45 animals) and examined microscopically for the presence of Amphimerus eggs. The prevalence of infection was 71.4% in cats and 38.7% in dogs, with similar rates of infection in all three communities. Significantly more cats were infected than dogs (p = 0.042). Conclusions/Significance The data show a high rate of Amphimerus sp. infection in domestic cats and dogs residing in Chachi communities. It can be concluded that these animals act as definitive and reservoir hosts for this liver fluke and that amphimeriasis is a zoonotic disease. These findings provide important epidemiological data which will aid in the development and implementation of control strategies against the transmission of Amphimerus. PMID:25647171

  19. Liver fluke control on sheep farms in Northern Ireland: A survey of changing management practices in relation to disease prevalence and perceived triclabendazole resistance.

    PubMed

    McMahon, C; Edgar, H W J; Hanna, R E B; Ellison, S E; Flanagan, A M; McCoy, M; Kajugu, P-E; Gordon, A W; Irwin, D; Barley, J E; Malone, F E; Brennan, G P; Fairweather, I

    2016-01-30

    Reports of resistance to triclabendazole (TCBZ) among fluke populations have increased in recent years. Allied to this, there has been a rise in the prevalence of the disease, which has been linked to climate change. Results from questionnaire surveys conducted in Northern Ireland (NI) in 2005 (covering the years 1999-2004) and 2011 (covering the years 2008-2011) have provided an opportunity to examine the extent to which fluke control practices have changed over a prolonged time-frame, in light of these changes. A number of differences were highlighted. There was a significant shift away from the use of TCBZ over time, with it being replaced largely by closantel. The timing of treatments had moved earlier in the year, perhaps in response to climate change (and an altered pattern of disease). In relation to the frequency of drug treatments, there were no major changes in the overall pattern of drug treatments between the two survey points, although on both occasions approximately one-third of flock owners gave more than 3 treatments per year to ewes. In lowland areas in 2011, flock owners were rotating drug classes more often (each year and at each treatment) than in 2005, whereas in upland areas, flock owners were rotating less often and more were not rotating at all. Between 2005 and 2011, the percentage of flock owners giving quarantine treatments to bought-in stock had halved, to a very low level (approximately 10%). Using data from a complementary TCBZ resistance survey (Hanna et al., 2015), it has been shown that the way in which data are selected and which efficacy formula is applied can influence the calculation of drug efficiency and impact on diagnosis of resistance.

  20. The immunologically reactive O-linked polysaccharide chains derived from circulating cathodic antigen isolated from the human blood fluke Schistosoma mansoni have Lewis x as repeating unit.

    PubMed

    Van Dam, G J; Bergwerff, A A; Thomas-Oates, J E; Rotmans, J P; Kamerling, J P; Vliegenthart, J F; Deelder, A M

    1994-10-01

    The gut-associated excretory antigen circulating cathodic antigen (CCA) was isolated by immunoaffinity chromatography from adult Schistosoma mansoni worms, which were collected from infected golden hamsters. This antigen is probably involved in protection of the schistosome gut and is increasingly used in highly sensitive and specific immunodiagnostic assays. Amino acid analysis before and after alkaline borohydride treatment of CCA and monosaccharide analysis indicated that CCA is O-glycosylated mostly via GalNAc-Thr. After reductive alkaline treatment, the O-linked carbohydrate chains were fractionated by gel-permeation chromatography, followed by normal-phase HPLC on LiChrosorb-NH2. Carbohydrate-positive fractions were investigated by one-dimensional and two-dimensional 1H-NMR spectroscopy, fast atom bombardment mass spectrometry and collision-induced-dissociation tandem mass spectrometry. The analyses showed that the low-molecular-mass O-linked oligosaccharide alditols (the minor fraction) consist of disaccharides to hexasaccharides having the Gal beta (1-3)GalNAc-OL core in common. The major carbohydrate fraction comprises a population of polysaccharides, containing Lewis x repeating units (-3)Gal beta (1-4)[Fuc alpha (1-3)]GlcNAc beta (1-). CCA-specific monoclonal antibodies and IgM antibodies in patient sera recognized the fucosylated O-linked carbohydrate antigenic structures. Since CCA evokes a strong IgM antibody response and carbohydrate structures containing repeating Lewis x units are found on circulating neutrophils, it is proposed that the antigenic poly-Lewis x polysaccharide of CCA is involved in the induction of auto-immunity against granulocytes, resulting in the mild to moderate neutropenia observed during schistosome infection.

  1. In Silico Analysis of the Fucosylation-Associated Genome of the Human Blood Fluke Schistosoma mansoni: Cloning and Characterization of the Fucosyltransferase Multigene Family

    PubMed Central

    Peterson, Nathan A.; Anderson, Tavis K.; Yoshino, Timothy P.

    2013-01-01

    Fucosylated glycans of the parasitic flatworm Schistosoma mansoni play key roles in its development and immunobiology. In the present study we used a genome-wide homology-based bioinformatics approach to search for genes that contribute to fucosylated glycan expression in S. mansoni, specifically the α2-, α3-, and α6-fucosyltransferases (FucTs), which transfer L-fucose from a GDP-L-fucose donor to an oligosaccharide acceptor. We identified and in silico characterized several novel schistosome FucT homologs, including six α3-FucTs and six α6-FucTs, as well as two protein O-FucTs that catalyze the unrelated transfer of L-fucose to serine and threonine residues of epidermal growth factor- and thrombospondin-type repeats. No α2-FucTs were observed. Primary sequence analyses identified key conserved FucT motifs as well as characteristic transmembrane domains, consistent with their putative roles as fucosyltransferases. Most genes exhibit alternative splicing, with multiple transcript variants generated. A phylogenetic analysis demonstrated that schistosome α3- and α6-FucTs form monophyletic clades within their respective gene families, suggesting multiple gene duplications following the separation of the schistosome lineage from the main evolutionary tree. Quantitative decreases in steady-state transcript levels of some FucTs during early larval development suggest a possible mechanism for differential expression of fucosylated glycans in schistosomes. This study systematically identifies the complete repertoire of FucT homologs in S. mansoni and provides fundamental information regarding their genomic organization, genetic variation, developmental expression, and evolutionary history. PMID:23696810

  2. New genus and species of fish blood fluke (Digenea: Aporocotylidae Odhner, 1912) from stoplight parrotfish, Sparisoma viride (Bonnaterre, 1788), (Labridae: Scarinae) in the Caribbean Sea.

    PubMed

    Bullard, Stephen A; Williams, Ernest H; Bunkley-Williams, Lucy

    2012-12-01

    Primisanguis caribbeanensis n. gen., n. sp. (Digenea: Aporocotylidae) infects the stoplight parrotfish, Sparisoma viride (Bonnaterre, 1788), (Labridae: Scarinae) in the Caribbean Sea off La Parguera (17°58'26" N, 67°02'47"W), Puerto Rico. It is most easily distinguished from other nominal aporocotylids by the combination of having an adult body that is approximately 5-10 times longer than wide, a sinistral posterolateral body protuberance, tegumental body spines that are straight (lacking recurved tip) and wrap dorsoventrally around the body margin, posterior ceca that are 2-5 times the anterior ceca length, a single testis that extends lateral to both the ceca and nerve cords, an ovary abutting the posterior margin of the testis, a symmetrical vitellarium and medial primary vitelline duct, a post-cecal and post-gonadal ootype, and a proximal uterus that is extensively convoluted posterior to the ootype and which functions as a uterine seminal receptacle. The new genus lacks a spinous anterior sucker, pharynx, auxiliary external seminal vesicle, cirrus stylet, oviducal seminal receptacle, and Laurer's canal. The new species is morphologically most similar to the other aporocotylids that have a posterolateral body protuberance, including species of Psettarium Goto and Ozaki, 1930, Aporocotyle Odhner, 1900, Ankistromeces Nolan and Cribb, 2004 , Phthinomita Nolan and Cribb, 2006, and Littorellicola Bullard, 2010, but it can be differentiated from them, at the least, by lack of a spinous anterior sucker in the adult and by the combination of having dorsoventral rows of tegumental spines, a testis dorsal to the posterior ceca, and a uterine seminal receptacle posterior to the ootype. The new species is the first aporocotylid reported from the Caribbean Sea or from a parrotfish of Sparisoma.

  3. Characterization of a female-specific cDNA derived from a developmentally regulated mRNA in the human blood fluke Schistosoma mansoni.

    PubMed

    Bobek, L; Rekosh, D M; van Keulen, H; LoVerde, P T

    1986-08-01

    We have isolated and characterized a cDNA clone that is derived from a developmentally regulated mRNA found only in mature female schistosomes. The mRNA is approximately 950 nucleotides in length and is not detectable in immature female schistosomes isolated from single-sex infections, in male worms, or in eggs. During normal bisexual infections, the mRNA species is first detected 28 days after infection (the time of worm pairing) and increases to a high level 35 days after infection, coinciding with the start of egg production. The nucleotide sequence of the cDNA shows two large open reading frames in the coding strand. Several features of the clone, including the deduced sequence of the polypeptide encoded by one of the reading frames, suggest a relationship to the silk moth chorion (egg shell) gene family. The isolation of this clone provides us with a probe for further studies of female schistosome development and is a first step toward a detailed understanding of this process at the molecular level.

  4. Cloning the genes and DNA binding properties of High Mobility Group B1 (HMGB1) proteins from the human blood flukes Schistosoma mansoni and Schistosoma japonicum.

    PubMed

    de Oliveira, Francisco Meirelles Bastos; de Abreu da Silva, Isabel Caetano; Rumjanek, Franklin David; Dias-Neto, Emmanuel; Guimarães, Pedro Edson Moreira; Verjovski-Almeida, Sergio; Stros, Michal; Fantappié, Marcelo Rosado

    2006-08-01

    The parasitic helminth Schistosoma mansoni contains three HMGB proteins, HMGB1, HMGB2 and HMGB3, of primary amino acid sequences highly similar to vertebrate proteins. In this report we describe the characterization of the HMGB1 proteins and their genes from S. mansoni and Schistosoma japonicum. The deduced amino acid sequences of HMGB1 proteins from both schistosome species are identical, and comprise 176 residues. The proteins contain the two evolutionarily highly conserved HMG-box domains, A and B, exhibiting 60% similarity to mammalian HMGB1. Unlike the human HMGB1 which contains an unbroken run of 30 glutamic or aspartic residues, the SmHMGB1 or SjHMGB1 proteins possess unusually short acidic C-terminal tails (5 acidic residues interrupted by 2 serines). Southern hybridization and DNA sequencing revealed a single copy HMGB1 gene, composed of 3 exons and two introns, in S. mansoni. The exon/intron boundaries are identical to those of the human HMGB1 gene, with the exception that the second exon of the SmHMGB1 gene which is not split into two exons as in the human HMGB1 gene. RNA blot analysis revealed that the SmHMGB1 gene is constitutively expressed in similar levels both in male and female worms. The single-sized mRNA for SmHMGB1 is consistent with the size derived from the cDNA. Although DNA binding properties of SmHMGB1 (or SjHMGB1) protein seem to be similar to those previously reported with human HMGB1, i.e., preferential binding to supercoiled DNA over linear DNA, specific recognition of DNA four-way junctions, DNA-induced supercoiling in the presence of topoisomerase I, and DNA bending, we have observed two important differences relative to those observed with the human HMGB1: (i) the inability of the isolated SmHMGB1 domain A to bend DNA (as revealed by T4 ligase-mediated circularization assay), and (ii) higher DNA supercoiling and bending potential of the SmHMGB1 protein as compared to its human counterpart. The latter finding may indicate that the long acidic C-tail of human HMGB1 has much stronger repressive role on DNA bending or DNA supercoiling by topoisomerase I at physiological ionic strength than the short C-tail of the SmHMGB1 protein. Considering the important role of HMGB1 in DNA replication, transcription, recombination, and in particularly, the mediation of inflammation responses in mammalian cells, further studies on schistosome HMGB proteins may provide valuable information related to schistosomiasis, where inflammation plays a critical role in this disease.

  5. In silico analysis of the fucosylation-associated genome of the human blood fluke Schistosoma mansoni: cloning and characterization of the fucosyltransferase multigene family.

    PubMed

    Peterson, Nathan A; Anderson, Tavis K; Yoshino, Timothy P

    2013-01-01

    Fucosylated glycans of the parasitic flatworm Schistosoma mansoni play key roles in its development and immunobiology. In the present study we used a genome-wide homology-based bioinformatics approach to search for genes that contribute to fucosylated glycan expression in S. mansoni, specifically the α2-, α3-, and α6-fucosyltransferases (FucTs), which transfer L-fucose from a GDP-L-fucose donor to an oligosaccharide acceptor. We identified and in silico characterized several novel schistosome FucT homologs, including six α3-FucTs and six α6-FucTs, as well as two protein O-FucTs that catalyze the unrelated transfer of L-fucose to serine and threonine residues of epidermal growth factor- and thrombospondin-type repeats. No α2-FucTs were observed. Primary sequence analyses identified key conserved FucT motifs as well as characteristic transmembrane domains, consistent with their putative roles as fucosyltransferases. Most genes exhibit alternative splicing, with multiple transcript variants generated. A phylogenetic analysis demonstrated that schistosome α3- and α6-FucTs form monophyletic clades within their respective gene families, suggesting multiple gene duplications following the separation of the schistosome lineage from the main evolutionary tree. Quantitative decreases in steady-state transcript levels of some FucTs during early larval development suggest a possible mechanism for differential expression of fucosylated glycans in schistosomes. This study systematically identifies the complete repertoire of FucT homologs in S. mansoni and provides fundamental information regarding their genomic organization, genetic variation, developmental expression, and evolutionary history.

  6. Early Warning and Prediction of Interest Attacks and Exploits

    DTIC Science & Technology

    2005-09-01

    EARLY WARNING AND PREDICTION OF INTERNET ATTACKS AND EXPLOITS THESIS Brian P. Zeitz... EARLY WARNING AND PREDICTION OF INTERNET ATTACKS AND EXPLOITS THESIS Presented to the Faculty Department of Electrical and Computer...RELEASE; DISTRIBUTION UNLIMITED iv AFIT/GIA/ENG/05-06 EARLY WARNING AND PREDICTION OF INTERNET ATTACKS AND EXPLOITS

  7. Virtual Exploitation Environment Demonstration for Atmospheric Missions

    NASA Astrophysics Data System (ADS)

    Natali, Stefano; Mantovani, Simone; Hirtl, Marcus; Santillan, Daniel; Triebnig, Gerhard; Fehr, Thorsten; Lopes, Cristiano

    2017-04-01

    The scientific and industrial communities are being confronted with a strong increase of Earth Observation (EO) satellite missions and related data. This is in particular the case for the Atmospheric Sciences communities, with the upcoming Copernicus Sentinel-5 Precursor, Sentinel-4, -5 and -3, and ESA's Earth Explorers scientific satellites ADM-Aeolus and EarthCARE. The challenge is not only to manage the large volume of data generated by each mission / sensor, but to process and analyze the data streams. Creating synergies among the different datasets will be key to exploit the full potential of the available information. As a preparation activity supporting scientific data exploitation for Earth Explorer and Sentinel atmospheric missions, ESA funded the "Technology and Atmospheric Mission Platform" (TAMP) [1] [2] project; a scientific and technological forum (STF) has been set-up involving relevant European entities from different scientific and operational fields to define the platforḿs requirements. Data access, visualization, processing and download services have been developed to satisfy useŕs needs; use cases defined with the STF, such as study of the SO2 emissions for the Holuhraun eruption (2014) by means of two numerical models, two satellite platforms and ground measurements, global Aerosol analyses from long time series of satellite data, and local Aerosol analysis using satellite and LIDAR, have been implemented to ensure acceptance of TAMP by the atmospheric sciences community. The platform pursues the "virtual workspace" concept: all resources (data, processing, visualization, collaboration tools) are provided as "remote services", accessible through a standard web browser, to avoid the download of big data volumes and for allowing utilization of provided infrastructure for computation, analysis and sharing of results. Data access and processing are achieved through standardized protocols (WCS, WPS). As evolution toward a pre

  8. Exploiting epigenetic vulnerabilities for cancer therapeutics.

    PubMed

    Mair, Barbara; Kubicek, Stefan; Nijman, Sebastian M B

    2014-03-01

    Epigenetic deregulation is a hallmark of cancer, and there has been increasing interest in therapeutics that target chromatin-modifying enzymes and other epigenetic regulators. The rationale for applying epigenetic drugs to treat cancer is twofold. First, epigenetic changes are reversible, and drugs could therefore be used to restore the normal (healthy) epigenetic landscape. However, it is unclear whether drugs can faithfully restore the precancerous epigenetic state. Second, chromatin regulators are often mutated in cancer, making them attractive drug targets. However, in most instances it is unknown whether cancer cells are addicted to these mutated chromatin proteins, or whether their mutation merely results in epigenetic instability conducive to the selection of secondary aberrations. An alternative incentive for targeting chromatin regulators is the exploitation of cancer-specific vulnerabilities, including synthetic lethality, caused by epigenetic deregulation. We review evidence for the hypothesis that mechanisms other than oncogene addiction are a basis for the application of epigenetic drugs, and propose future research directions.

  9. Redressing China's strategy of water resource exploitation.

    PubMed

    Ran, Lishan; Lu, Xi Xi

    2013-03-01

    China, with the confrontation of water-related problems as an element of its long history, has been investing heavily in water engineering projects over the past few decades based on the assumption that these projects can solve its water problems. However, the anticipated benefits did not really occur, or at least not as large as expected. Instead, the results involved additional frustrations, such as biodiversity losses and human-induced disasters (i.e., landslides and earthquakes). Given its inherent shortcomings, the present engineering-dominated strategy for the management of water resources cannot help solve China's water problems and achieve its goal of low-carbon transformation. Therefore, the present strategy for water resources exploitation needs to be reevaluated and redressed. A policy change to achieve better management of Chinese rivers is urgently needed.

  10. Digital video steganalysis exploiting collusion sensitivity

    NASA Astrophysics Data System (ADS)

    Budhia, Udit; Kundur, Deepa

    2004-09-01

    In this paper we present an effective steganalyis technique for digital video sequences based on the collusion attack. Steganalysis is the process of detecting with a high probability and low complexity the presence of covert data in multimedia. Existing algorithms for steganalysis target detecting covert information in still images. When applied directly to video sequences these approaches are suboptimal. In this paper, we present a method that overcomes this limitation by using redundant information present in the temporal domain to detect covert messages in the form of Gaussian watermarks. Our gains are achieved by exploiting the collusion attack that has recently been studied in the field of digital video watermarking, and more sophisticated pattern recognition tools. Applications of our scheme include cybersecurity and cyberforensics.

  11. Explosives Detection: Exploitation of the Physical Signatures

    NASA Astrophysics Data System (ADS)

    Atkinson, David

    2010-10-01

    Explosives based terrorism is an ongoing threat that is evolving with respect to implementation, configuration and materials used. There are a variety of devices designed to detect explosive devices, however, each technology has limitations and operational constraints. A full understanding of the signatures available for detection coupled with the array of detection choices can be used to develop a conceptual model of an explosives screening operation. Physics based sensors provide a robust approach to explosives detection, typically through the identification of anomalies, and are currently used for screening in airports around the world. The next generation of detectors for explosives detection will need to be more sensitive and selective, as well as integrate seamlessly with devices focused on chemical signatures. An appreciation for the details of the physical signature exploitation in cluttered environments with time, space, and privacy constraints is necessary for effective explosives screening of people, luggage, cargo, and vehicles.

  12. Iron and Zinc Exploitation during Bacterial Pathogenesis

    PubMed Central

    Ma, Li; Terwilliger, Austen; Maresso, Anthony W.

    2016-01-01

    Ancient bacteria originated from metal-rich environments. Billions of years of evolution directed these tiny single cell creatures to exploit the versatile properties of metals in catalyzing chemical reactions and biological responses. The result is an entire metallome of proteins that use metal co-factors to facilitate key cellular process that range from the production of energy to the replication of DNA. Two key metals in this regard are iron and zinc, both abundant on Earth but not readily accessible in a human host. Instead, pathogenic bacteria must employ clever ways to acquire these metals. In this review we describe the many elegant ways these bacteria mine, regulate, and craft the use of two key metals (iron and zinc) to build a virulence arsenal that challenges even the most sophisticated immune response. PMID:26497057

  13. Are Youths' Feelings of Entitlement Always "Bad"?: Evidence for a Distinction between Exploitive and Non-Exploitive Dimensions of Entitlement

    ERIC Educational Resources Information Center

    Lessard, Jared; Greenberger, Ellen; Chen, Chuansheng; Farruggia, Susan

    2011-01-01

    Previous personality research (e.g., Campbell et al., 2004) has described the sense of entitlement as an unifactorial construct. In this study, we examined characteristics of two potential facets of entitlement: exploitive entitlement, characterized by exploitive interactions and expectations of special treatment, and non-exploitive entitlement,…

  14. Are Youths' Feelings of Entitlement Always "Bad"?: Evidence for a Distinction between Exploitive and Non-Exploitive Dimensions of Entitlement

    ERIC Educational Resources Information Center

    Lessard, Jared; Greenberger, Ellen; Chen, Chuansheng; Farruggia, Susan

    2011-01-01

    Previous personality research (e.g., Campbell et al., 2004) has described the sense of entitlement as an unifactorial construct. In this study, we examined characteristics of two potential facets of entitlement: exploitive entitlement, characterized by exploitive interactions and expectations of special treatment, and non-exploitive entitlement,…

  15. Donating Blood

    MedlinePlus

    ... can't get an infection or disease from giving blood. The needles and other equipment used are sterile ... part of blood (plasma) within 72 hours after giving blood. It generally takes about 4–8 weeks to ...

  16. Blood Sugar

    MedlinePlus

    Blood sugar, or glucose, is the main sugar found in your blood. It comes from the food you eat, and is your body's main source of energy. Your blood carries glucose to all of your body's cells to use ...

  17. GOCE Exploitation for Moho Modeling and Applications

    NASA Astrophysics Data System (ADS)

    Sampierto, D.

    2011-07-01

    New ESA missions dedicated to the observation of the Earth from space, like the gravity-gradiometry mission GOCE and the radar altimetry mission CRYOSAT 2, foster research, among other subjects, also on inverse gravimetric problems and on the description of the nature and the geographical location of gravimetric signals. In this framework the GEMMA project (GOCE Exploitation for Moho Modeling and Applications), funded by the European Space Agency and Politecnico di Milano, aims at estimating the boundary between Earth's crust and mantle (the so called Mohorovičić discontinuity or Moho) from GOCE data in key regions of the world. In the project a solution based on a simple two layer model in spherical approximation is proposed. This inversion problem based on the linearization of the Newton's gravitational law around an approximate mean Moho surface will be solved by exploiting Wiener-Kolmogorov theory in the frequency domain where the depth of the Moho discontinuity will be treated as a random signal with a zero mean and its own covariance function. The algorithm can be applied in a numerically efficient way by using the Fast Fourier Transform. As for the gravity observations, we will consider grids of the anomalous gravitational potential and its second radial derivative at satellite altitude. In particular this will require first of all to elaborate GOCE data to obtain a local grid of the gravitational potential field and its second radial derivative and after that to separate the gravimetric signal due to the considered discontinuity from the gravitational effects of other geological structures present into the observations. The first problem can be solved by applying the so called space- wise approach to GOCE observations, while the second one can be achieved by considering a priori models and geophysical information by means of an appropriate Bayesan technique. Moreover other data such as ground gravity anomalies or seismic profiles can be combined, in an

  18. Mission Exploitation Platform PROBA-V

    NASA Astrophysics Data System (ADS)

    Goor, Erwin

    2016-04-01

    VITO and partners developed an end-to-end solution to drastically improve the exploitation of the PROBA-V EO-data archive (http://proba-v.vgt.vito.be/), the past mission SPOT-VEGETATION and derived vegetation parameters by researchers, service providers and end-users. The analysis of time series of data (+1PB) is addressed, as well as the large scale on-demand processing of near real-time data. From November 2015 an operational Mission Exploitation Platform (MEP) PROBA-V, as an ESA pathfinder project, will be gradually deployed at the VITO data center with direct access to the complete data archive. Several applications will be released to the users, e.g. - A time series viewer, showing the evolution of PROBA-V bands and derived vegetation parameters for any area of interest. - Full-resolution viewing services for the complete data archive. - On-demand processing chains e.g. for the calculation of N-daily composites. - A Virtual Machine will be provided with access to the data archive and tools to work with this data, e.g. various toolboxes and support for R and Python. After an initial release in January 2016, a research platform will gradually be deployed allowing users to design, debug and test applications on the platform. From the MEP PROBA-V, access to Sentinel-2 and landsat data will be addressed as well, e.g. to support the Cal/Val activities of the users. Users can make use of powerful Web based tools and can self-manage virtual machines to perform their work on the infrastructure at VITO with access to the complete data archive. To realise this, private cloud technology (openStack) is used and a distributed processing environment is built based on Hadoop. The Hadoop ecosystem offers a lot of technologies (Spark, Yarn, Accumulo, etc.) which we integrate with several open-source components. The impact of this MEP on the user community will be high and will completely change the way of working with the data and hence open the large time series to a larger

  19. Exploiting apoptosis in photodynamic therapy: is it possible?

    NASA Astrophysics Data System (ADS)

    Rendon, Cesar A.; Lilge, Lothar D.

    2003-06-01

    Glioblastoma Multiforme is the most common form of malignant brain tumors and accounts for approximately 25% of all primary brain tumors. Only 5% of these patients survive longer than 2 years. The standard form of treatment is radiation therapy and surgery if the site is accessible. Different forms of adjuvant chemotherapy have been largely proven unsuccessful. Another form of adjuvant therapy, Photodynamic Therapy (PDT), has undergone preliminary trials showing some promising results but at the cost of increased side effects like rise in intracranial blood pressure and neurological deficiency. Apoptotic cell kill used as a biological treatment endpoint can possibly ameliorate these side effects. This study evaluates the significance of apoptotic cell death in the 9L rat gliosarcoma using the aminolevulinic acid (ALA) induced endogenous photosensitizer Protophorphyrin IX (PpIX). A strong influence of drug incubation time with cell kill was observed. The percentage of apoptotic cell death was less than 10% for 2 and 4 hours incubation times and irradiation times ensuring up to 70 and 80% cell kill respectively. Accumulation of PpIX in the mitochondria and cytoplasm was quantified by confocal fluorescence microscopy showing a linear relationship of PpIX fluorescence with concentration. The possibility of an in vitro threshold in the PDT dose is discussed, above which cell repair mechanisms may become exhausted. In conclusion for the range of parameters investigated, apoptotic cell kill may be hard to exploit therapeutically in this tumor model.

  20. Generating circuit tests by exploiting designed behavior

    NASA Astrophysics Data System (ADS)

    Shirley, Mark H.

    1988-12-01

    Generating tests for sequential devices is one of the hardest problems in designing and manufacturing digital circuits. This task is difficult primarily because internal components are accessible only indirectly, forcing a test generator to use the surrounding components collectively as a probe for detecting faults. This in turn forces the test generator to reason about complex interactions between the behaviors of these surrounding components. Current automated solutions are becoming ineffective as designs grow larger and more complex. Yet, despite the complexity, human experts remain remarkably successful, in part, because they use knowledge from many sources and use a variety of reasoning techniques. This thesis exploits several kinds of expert knowledge about circuits and test generation not used by the current algorithms. First, many test generation problems can be solved efficiently using operation relations, a novel representation of circuit behavior that connects internal component operations with directly executable circuit operations. Operation relations can be computed efficiently for sequential circuits that provide few operations at their interfaces by searching traces of simulated circuit behavior. Second, experts write test programs rather than test vectors because programs are a more readable and compact representation for tests than vectors are. Test programs can be constructed automatically by merging test program fragments using expert supplied goal-refined rules and domain independent planning techniques from artificial intelligence.

  1. The Spanish network for Gaia Science Exploitation

    NASA Astrophysics Data System (ADS)

    Figueras, F.; Jordi, C.; Luri, X.; Torra, J.; REG Executive Committee Team; Gaia UB Team

    2017-03-01

    The ''Red Española de Explotación Científica de Gaia'' (REG) continues to intensify its activities facing the imminent publication of the first and second Gaia data releases (14 September, 2016 and Q4-2017, respectively). The network, supported by the MINECO under contract Acciones de dinamizaci ´on, Redes de Excelencia (2016-2017), has as major priority the task to coordinate and support the collective activities developed by its more than 150 members. At present, REG plays a prominent role in the preparation of the Spanish community for the use of the Gaia data archive (a task lead by the Spanish team), in the work to exploit the Gaia-ESO survey collected during the last four years and in supporting the preparation of the science case and survey plan for WEAVE, the new multi-object spectrograph for the WHT at Canary Islands (commissioning, 2018). These activities are described together with the schedule of future national and international science meetings and the outreach activities being organized for the first and second Data Releases

  2. Examining the potential exploitation of UNOS policies.

    PubMed

    Zink, Sheldon; Wertlieb, Stacey; Catalano, John; Marwin, Victor

    2005-01-01

    The United Network for Organ Sharing (UNOS) waiting list was designed as a just and equitable system through which the limited number of organs is allocated to the millions of Americans in need of a transplant. People have trusted the system because of the belief that everyone on the list has an equal opportunity to receive an organ and also that allocation is blind to matters of financial standing, celebrity or political power. Recent events have revealed that certain practices and policies have the potential to be exploited. The policies addressed in this paper enable those on the list with the proper resources to gain an advantage over other less fortunate members, creating a system that benefits not the individual most in medical need, but the one with the best resources. These policies are not only unethical but threaten the balance and success of the entire UNOS system. This paper proposes one possible solution, which seeks to balance the concepts of justice and utility.

  3. Haploids in flowering plants: origins and exploitation.

    PubMed

    Dunwell, Jim M

    2010-05-01

    The first haploid angiosperm, a dwarf form of cotton with half the normal chromosome complement, was discovered in 1920, and in the ninety years since then such plants have been identified in many other species. They can occur either spontaneously or can be induced by modified pollination methods in vivo, or by in vitro culture of immature male or female gametophytes. Haploids represent an immediate, one-stage route to homozygous diploids and thence to F(1) hybrid production. The commercial exploitation of heterosis in such F(1) hybrids leads to the development of hybrid seed companies and subsequently to the GM revolution in agriculture. This review describes the range of techniques available for the isolation or induction of haploids and discusses their value in a range of areas, from fundamental research on mutant isolation and transformation, through to applied aspects of quantitative genetics and plant breeding. It will also focus on how molecular methods have been used recently to explore some of the underlying aspects of this fascinating developmental phenomenon.

  4. Relationship between exploitation, oscillation, MSY and extinction.

    PubMed

    Ghosh, Bapan; Kar, T K; Legovic, T

    2014-10-01

    We give answers to two important problems arising in current fisheries: (i) how maximum sustainable yield (MSY) policy is influenced by the initial population level, and (ii) how harvesting, oscillation and MSY are related to each other in prey-predator systems. To examine the impact of initial population on exploitation, we analyze a single species model with strong Allee effect. It is found that even when the MSY exists, the dynamic solution may not converge to the equilibrium stock if the initial population level is higher but near the critical threshold level. In a prey-predator system with Allee effect in the prey species, the initial population does not have such important impact neither on MSY nor on maximum sustainable total yield (MSTY). However, harvesting the top predator may cause extinction of all species if odd number of trophic levels exist in the ecosystem. With regard to the second problem, we study two prey-predator models and establish that increasing harvesting effort either on prey, predator or both prey and predator destroys previously existing oscillation. Moreover, equilibrium stock both at MSY and MSTY level is stable. We also discuss the validity of found results to other prey-predator systems.

  5. Exploiting spatial descriptions in visual scene analysis.

    PubMed

    Ziegler, Leon; Johannsen, Katrin; Swadzba, Agnes; De Ruiter, Jan P; Wachsmuth, Sven

    2012-08-01

    The reliable automatic visual recognition of indoor scenes with complex object constellations using only sensor data is a nontrivial problem. In order to improve the construction of an accurate semantic 3D model of an indoor scene, we exploit human-produced verbal descriptions of the relative location of pairs of objects. This requires the ability to deal with different spatial reference frames (RF) that humans use interchangeably. In German, both the intrinsic and relative RF are used frequently, which often leads to ambiguities in referential communication. We assume that there are certain regularities that help in specific contexts. In a first experiment, we investigated how speakers of German describe spatial relationships between different pieces of furniture. This gave us important information about the distribution of the RFs used for furniture-predicate combinations, and by implication also about the preferred spatial predicate. The results of this experiment are compiled into a computational model that extracts partial orderings of spatial arrangements between furniture items from verbal descriptions. In the implemented system, the visual scene is initially scanned by a 3D camera system. From the 3D point cloud, we extract point clusters that suggest the presence of certain furniture objects. We then integrate the partial orderings extracted from the verbal utterances incrementally and cumulatively with the estimated probabilities about the identity and location of objects in the scene, and also estimate the probable orientation of the objects. This allows the system to significantly improve both the accuracy and richness of its visual scene representation.

  6. Exploiting interspecific olfactory communication to monitor predators.

    PubMed

    Garvey, Patrick M; Glen, Alistair S; Clout, Mick N; Wyse, Sarah V; Nichols, Margaret; Pech, Roger P

    2017-03-01

    Olfaction is the primary sense of many mammals and subordinate predators use this sense to detect dominant species, thereby reducing the risk of an encounter and facilitating coexistence. Chemical signals can act as repellents or attractants and may therefore have applications for wildlife management. We devised a field experiment to investigate whether dominant predator (ferret Mustela furo) body odor would alter the behavior of three common mesopredators: stoats (Mustela erminea), hedgehogs (Erinaceus europaeus), and ship rats (Rattus rattus). We predicted that apex predator odor would lead to increased detections, and our results support this hypothesis as predator kairomones (interspecific olfactory messages that benefit the receiver) provoked "eavesdropping" behavior by mesopredators. Stoats exhibited the most pronounced responses, with kairomones significantly increasing the number of observations and the time spent at a site, so that their occupancy estimates changed from rare to widespread. Behavioral responses to predator odors can therefore be exploited for conservation and this avenue of research has not yet been extensively explored. A long-life lure derived from apex predator kairomones could have practical value, especially when there are plentiful resources that reduce the efficiency of food-based lures. Our results have application for pest management in New Zealand and the technique of using kairomones to monitor predators could have applications for conservation efforts worldwide.

  7. Exploiting intrinsic fluctuations to identify model parameters.

    PubMed

    Zimmer, Christoph; Sahle, Sven; Pahle, Jürgen

    2015-04-01

    Parameterisation of kinetic models plays a central role in computational systems biology. Besides the lack of experimental data of high enough quality, some of the biggest challenges here are identification issues. Model parameters can be structurally non-identifiable because of functional relationships. Noise in measured data is usually considered to be a nuisance for parameter estimation. However, it turns out that intrinsic fluctuations in particle numbers can make parameters identifiable that were previously non-identifiable. The authors present a method to identify model parameters that are structurally non-identifiable in a deterministic framework. The method takes time course recordings of biochemical systems in steady state or transient state as input. Often a functional relationship between parameters presents itself by a one-dimensional manifold in parameter space containing parameter sets of optimal goodness. Although the system's behaviour cannot be distinguished on this manifold in a deterministic framework it might be distinguishable in a stochastic modelling framework. Their method exploits this by using an objective function that includes a measure for fluctuations in particle numbers. They show on three example models, immigration-death, gene expression and Epo-EpoReceptor interaction, that this resolves the non-identifiability even in the case of measurement noise with known amplitude. The method is applied to partially observed recordings of biochemical systems with measurement noise. It is simple to implement and it is usually very fast to compute. This optimisation can be realised in a classical or Bayesian fashion.

  8. GOCE: mission accomplished but exploitation continues

    NASA Astrophysics Data System (ADS)

    Floberghagen, Rune; Fehringer, Michael; Steiger, Christoph; Romanazzo, Massimo; Frommknecht, Bjoern; Klinkrad, Heiner

    2014-05-01

    Launched in March 2009 into an extremely low Earth orbit on an originally 20-months mission to map the quasi-static gravity field, the GOCE satellite more than tripled its expected measurement return. Being the lowest orbiting research satellite since the beginning, GOCE underwent a series of orbit lowerings towards the end of its lifetime in order to further maximise the signal content (both in amplitude and scale) of the gravity gradient and hi-lo satellite-to-satellite observations. Gravity field mapping in drag-compensation mode at 224 km altitude was completed on 21 October 2013, after which the satellite rapidly decayed deeper into the upper layers of the atmosphere. During this phase all instruments and avionics equipment were acquiring data. Finally, the satellite re-entered over the South Atlantic ocean in the very early hours of 11 November 2013 (UTC). This contribution describes the science return of GOCE in its final phase, including the de-orbiting and re-entry phase. It provides an overview of the impact of GOCE in the earth sciences, incl. geodesy, oceanography, solid earth and aeronomy. Plans for continued exploitation of GOCE data - within and outside the context of the European Space Agency programmes - will be also presented.

  9. Exploiting core knowledge for visual object recognition.

    PubMed

    Schurgin, Mark W; Flombaum, Jonathan I

    2017-03-01

    Humans recognize thousands of objects, and with relative tolerance to variable retinal inputs. The acquisition of this ability is not fully understood, and it remains an area in which artificial systems have yet to surpass people. We sought to investigate the memory process that supports object recognition. Specifically, we investigated the association of inputs that co-occur over short periods of time. We tested the hypothesis that human perception exploits expectations about object kinematics to limit the scope of association to inputs that are likely to have the same token as a source. In several experiments we exposed participants to images of objects, and we then tested recognition sensitivity. Using motion, we manipulated whether successive encounters with an image took place through kinematics that implied the same or a different token as the source of those encounters. Images were injected with noise, or shown at varying orientations, and we included 2 manipulations of motion kinematics. Across all experiments, memory performance was better for images that had been previously encountered with kinematics that implied a single token. A model-based analysis similarly showed greater memory strength when images were shown via kinematics that implied a single token. These results suggest that constraints from physics are built into the mechanisms that support memory about objects. Such constraints-often characterized as 'Core Knowledge'-are known to support perception and cognition broadly, even in young infants. But they have never been considered as a mechanism for memory with respect to recognition. (PsycINFO Database Record

  10. Exploiting fungal cell wall components in vaccines

    PubMed Central

    Levitz, Stuart M.; Huang, Haibin; Ostroff, Gary R.; Specht, Charles A.

    2014-01-01

    Innate recognition of fungi leads to strong adaptive immunity. Investigators are trying to exploit this observation in vaccine development by combining antigens with evolutionarily conserved fungal cell wall carbohydrates to induce protective responses. Best studied is β-1,3-glucan, a glycan that activates complement and is recognized by Dectin-1. Administration of antigens in association with β-1,3-glucan, either by direct conjugation or complexed in glucan particles, results in robust humoral and cellular immune responses. While the host has a host of mannose receptors, responses to fungal mannoproteins generally are amplified if cells are cooperatively stimulated with an additional danger signal such as a toll-like receptor agonist. Chitosan, a polycationic homopolymer of glucosamine manufactured by the deacetylation of chitin, is being studied as an adjuvant in DNA and protein-based vaccines. It appears particularly promising in mucosal vaccines. Finally, universal and organism-specific fungal vaccines have been formulated by conjugating fungal cell wall glycans to carrier proteins. A major challenge will be to advance these experimental findings so that at risk patients can be protected. PMID:25404118

  11. Tonic Dopamine Modulates Exploitation of Reward Learning

    PubMed Central

    Beeler, Jeff A.; Daw, Nathaniel; Frazier, Cristianne R. M.; Zhuang, Xiaoxi

    2010-01-01

    The impact of dopamine on adaptive behavior in a naturalistic environment is largely unexamined. Experimental work suggests that phasic dopamine is central to reinforcement learning whereas tonic dopamine may modulate performance without altering learning per se; however, this idea has not been developed formally or integrated with computational models of dopamine function. We quantitatively evaluate the role of tonic dopamine in these functions by studying the behavior of hyperdopaminergic DAT knockdown mice in an instrumental task in a semi-naturalistic homecage environment. In this “closed economy” paradigm, subjects earn all of their food by pressing either of two levers, but the relative cost for food on each lever shifts frequently. Compared to wild-type mice, hyperdopaminergic mice allocate more lever presses on high-cost levers, thus working harder to earn a given amount of food and maintain their body weight. However, both groups show a similarly quick reaction to shifts in lever cost, suggesting that the hyperdominergic mice are not slower at detecting changes, as with a learning deficit. We fit the lever choice data using reinforcement learning models to assess the distinction between acquisition and expression the models formalize. In these analyses, hyperdopaminergic mice displayed normal learning from recent reward history but diminished capacity to exploit this learning: a reduced coupling between choice and reward history. These data suggest that dopamine modulates the degree to which prior learning biases action selection and consequently alters the expression of learned, motivated behavior. PMID:21120145

  12. Accelerating Large Data Analysis By Exploiting Regularities

    NASA Technical Reports Server (NTRS)

    Moran, Patrick J.; Ellsworth, David

    2003-01-01

    We present techniques for discovering and exploiting regularity in large curvilinear data sets. The data can be based on a single mesh or a mesh composed of multiple submeshes (also known as zones). Multi-zone data are typical to Computational Fluid Dynamics (CFD) simulations. Regularities include axis-aligned rectilinear and cylindrical meshes as well as cases where one zone is equivalent to a rigid-body transformation of another. Our algorithms can also discover rigid-body motion of meshes in time-series data. Next, we describe a data model where we can utilize the results from the discovery process in order to accelerate large data visualizations. Where possible, we replace general curvilinear zones with rectilinear or cylindrical zones. In rigid-body motion cases we replace a time-series of meshes with a transformed mesh object where a reference mesh is dynamically transformed based on a given time value in order to satisfy geometry requests, on demand. The data model enables us to make these substitutions and dynamic transformations transparently with respect to the visualization algorithms. We present results with large data sets where we combine our mesh replacement and transformation techniques with out-of-core paging in order to achieve significant speed-ups in analysis.

  13. Understanding Online Child Sexual Exploitation Offenses.

    PubMed

    Ly, Thanh; Murphy, Lisa; Fedoroff, J Paul

    2016-08-01

    In the past three decades, there has been an exponential increase in the worldwide availability of Internet access and devices that are able to access online materials. This literature review investigated whether increased accessibility of Internet child pornography (CP) increases the risk of in-person child sexual exploitation. The current review found little to no evidence that availability of the Internet has increased the worldwide incidence or prevalence of in-person child sexual abuse. In fact, during the time period in which the Internet has flourished, international crime statistics have shown a steady decrease of in-person child sexual abuse. The only exception to this trend is an increase in Internet child pornography or luring offenses (e.g., Stats Can, 2014), which involves child abuse by definition. This article reviews the impact of the Internet on child sexual abuse. It also reviews the characteristics of online CP offenders. Treatment of these offenders and prevention of such offenses is also discussed.

  14. Exploiting protein intrinsic flexibility in drug design.

    PubMed

    Lukman, Suryani; Verma, Chandra S; Fuentes, Gloria

    2014-01-01

    Molecular recognition in biological systems relies on the existence of specific attractive interactions between two partner molecules. Structure-based drug design seeks to identify and optimize such interactions between ligands and their protein targets. The approach followed in medicinal chemistry follows a combination of careful analysis of structural data together with experimental and/or theoretical studies on the system. This chapter focuses on the fact that a protein is not fully characterized by a single structure, but by an ensemble of states, some of them represent "hidden conformations" with cryptic binding sites. We highlight case studies where both experimental and computational methods have been used to mutually drive each other in an attempt to improve the success of the drug design approaches.Advances in both experimental techniques and computational methods have greatly improved our physico-chemical understanding of the functional mechanisms in biomolecules and opened a debate about the interplay between molecular structure and biomolecular function. The beautiful static pictures of protein structures may have led to neglecting the intrinsic protein flexibility, however we are entering a new era where more sophisticated methods are used to exploit this ability of macromolecules, and this will definitely lead to the inclusion of the notion in the pharmaceutical field of drug design.

  15. Competing Discourses about Youth Sexual Exploitation in Canadian News Media

    PubMed Central

    Saewyc, Elizabeth M.; Miller, Bonnie B.; Rivers, Robert; Matthews, Jennifer; Hilario, Carla; Hirakata, Pam

    2015-01-01

    Media holds the power to create, maintain, or break down stigmatizing attitudes, which affect policies, funding, and services. To understand how Canadian news media depicts the commercial sexual exploitation of children and youth, we examined 835 Canadian newspaper articles from 1989–2008 using a mixed methods critical discourse analysis approach, comparing representations to existing research about sexually exploited youth. Despite research evidence that equal rates of boys and girls experience exploitation, Canadian news media depicted exploited youth predominantly as heterosexual girls, and described them alternately as victims or workers in a trade, often both in the same story. News media mentioned exploiters far less often than victims, and portrayed them almost exclusively as male, most often called ‘customers’ or ‘consumers,’ and occasionally ‘predators’; in contrast, research has documented the majority of sexually exploited boys report female exploiters. Few news stories over the past two decades portrayed the diversity of victims, perpetrators, and venues of exploitation reported in research. The focus on victims but not exploiters helps perpetuate stereotypes of sexual exploitation as business or a ‘victimless crime,’ maintains the status quo, and blurs responsibility for protecting youth under the UN Convention on the Rights of the Child. Health care providers and researchers can be advocates for accuracy in media coverage about sexual exploitation; news reporters and editors should focus on exploiters more than victims, draw on existing research evidence to avoid perpetuating stereotypes, and use accurate terms, such as commercial sexual exploitation, rather than terms related to business or trade. PMID:26793015

  16. Fasciola hepatica: Specificity of a coproantigen ELISA test for diagnosis of fasciolosis in faecal samples from cattle and sheep concurrently infected with gastrointestinal nematodes, coccidians and/or rumen flukes (paramphistomes), under field conditions.

    PubMed

    Kajugu, P-E; Hanna, R E B; Edgar, H W; McMahon, C; Cooper, M; Gordon, A; Barley, J P; Malone, F E; Brennan, G P; Fairweather, I

    2015-09-15

    Chronic fasciolosis is often diagnosed by faecal egg counting (FEC), following concentration of the eggs in the sample by a zinc sulphate floatation method. However, concentration by a sedimentation technique gives improved sensitivity. Interpretation of FEC results for fasciolosis is complicated by factors such as the long pre-patent period and irregular egg shedding. Thus, FEC reduction tests (FECRT), when used alone, are not completely reliable for diagnosis of anthelmintic susceptibility or resistance in local fluke populations, especially when parasite burdens are small. A Fasciola hepatica coproantigen ELISA test has been introduced which more accurately reflects the presence of flukes in the host bile ducts in late pre-patent infections, and absence of flukes following successful chemotherapeutic intervention. The aim of the present study was to elucidate the specificity of the F. hepatica coproantigen ELISA technique, particularly regarding potential cross-reactivity with rumen fluke (paramphistome), gastrointestinal nematode and coccidian infections. The method involved parallel testing of a large battery of faecal samples from field-infected cattle and sheep using floatation and sedimentation FECs and coproantigen analysis. No evidence was found for significant false positivity in the F. hepatica coproantigen ELISA due to paramphistome, coccidian and/or gastrointestinal nematode co-infections. With sedimentation FECs less than 10 F. hepatica eggs per gram (epg), the likelihood of a positive coproantigen result for the sample progressively decreased. Diagnosis of fasciolosis should be based on consideration of both FEC and coproantigen ELISA findings, to ensure optimum sensitivity for pre-patent and low-level infections.

  17. What's Blood?

    MedlinePlus

    ... Let's find out more about each ingredient. continue Red Blood Cells Red blood cells (also called erythrocytes, say: ih-RITH-ruh-sytes) ... Most of the cells in the blood are red blood cells. They carry around an important chemical called hemoglobin ( ...

  18. Artificial Blood for Dogs.

    PubMed

    Yamada, Kana; Yokomaku, Kyoko; Kureishi, Moeka; Akiyama, Motofusa; Kihira, Kiyohito; Komatsu, Teruyuki

    2016-11-10

    There is no blood bank for pet animals. Consequently, veterinarians themselves must obtain "blood" for transfusion therapy. Among the blood components, serum albumin and red blood cells (RBCs) are particularly important to save lives. This paper reports the synthesis, structure, and properties of artificial blood for the exclusive use of dogs. First, recombinant canine serum albumin (rCSA) was produced using genetic engineering with Pichia yeast. The proteins showed identical features to those of the native CSA derived from canine plasma. Furthermore, we ascertained the crystal structure of rCSA at 3.2 Å resolution. Pure rCSA can be used widely for numerous clinical and pharmaceutical applications. Second, hemoglobin wrapped covalently with rCSA, hemoglobin-albumin cluster (Hb-rCSA3), was synthesized as an artificial O2-carrier for the RBC substitute. This cluster possesses satisfactorily negative surface net charge (pI = 4.7), which supports enfolding of the Hb core by rCSA shells. The anti-CSA antibody recognized the rCSA exterior quantitatively. The O2-binding affinity was high (P50 = 9 Torr) compared to that of the native Hb. The Hb-rCSA3 cluster is anticipated for use as an alternative material for RBC transfusion, and as an O2 therapeutic reagent that can be exploited in various veterinary medicine situations.

  19. Aspects of abuse: commercial sexual exploitation of children.

    PubMed

    Jimenez, Melissa; Jackson, Allison M; Deye, Katherine

    2015-03-01

    Commercial sexual exploitation of children (CSEC) and adolescents is a serious worldwide problem. It is, in essence, the sexual abuse of a minor for economic gain. In the United States, there is no uniform nationwide database to capture the incidence and prevalence of CSEC. Therefore, there is a great variation in the estimates, but the actual numbers are unknown. Given the clandestine nature of the practice, it is often underreported and underidentified. Healthcare providers will often encounter victims of commercial sexual exploitation due to mental health, physical health, and sexual health consequences, and therefore should be knowledgeable in the signs of possible sexual exploitation. The aim of this article is to educate healthcare providers on how vulnerable children may become sexually exploited, the health consequences involved with sexual exploitation, how to better identify possible victims, and the medical evaluation of a victim of sexual exploitation. Copyright © 2015 Mosby, Inc. All rights reserved.

  20. Transnational gestational surrogacy: does it have to be exploitative?

    PubMed

    Kirby, Jeffrey

    2014-01-01

    This article explores the controversial practice of transnational gestational surrogacy and poses a provocative question: Does it have to be exploitative? Various existing models of exploitation are considered and a novel exploitation-evaluation heuristic is introduced to assist in the analysis of the potentially exploitative dimensions/elements of complex health-related practices. On the basis of application of the heuristic, I conclude that transnational gestational surrogacy, as currently practiced in low-income country settings (such as rural, western India), is exploitative of surrogate women. Arising out of consideration of the heuristic's exploitation conditions, a set of public education and enabled choice, enhanced protections, and empowerment reforms to transnational gestational surrogacy practice is proposed that, if incorporated into a national regulatory framework and actualized within a low income country, could possibly render such practice nonexploitative.

  1. Proba-V Mission Exploitation Platform

    NASA Astrophysics Data System (ADS)

    Goor, Erwin; Dries, Jeroen

    2017-04-01

    VITO and partners developed the Proba-V Mission Exploitation Platform (MEP) as an end-to-end solution to drastically improve the exploitation of the Proba-V (a Copernicus contributing mission) EO-data archive (http://proba-v.vgt.vito.be/), the past mission SPOT-VEGETATION and derived vegetation parameters by researchers, service providers and end-users. The analysis of time series of data (+1PB) is addressed, as well as the large scale on-demand processing of near real-time data on a powerful and scalable processing environment. Furthermore data from the Copernicus Global Land Service is in scope of the platform. From November 2015 an operational Proba-V MEP environment, as an ESA operation service, is gradually deployed at the VITO data center with direct access to the complete data archive. Since autumn 2016 the platform is operational and yet several applications are released to the users, e.g. - A time series viewer, showing the evolution of Proba-V bands and derived vegetation parameters from the Copernicus Global Land Service for any area of interest. - Full-resolution viewing services for the complete data archive. - On-demand processing chains on a powerfull Hadoop/Spark backend e.g. for the calculation of N-daily composites. - Virtual Machines can be provided with access to the data archive and tools to work with this data, e.g. various toolboxes (GDAL, QGIS, GrassGIS, SNAP toolbox, …) and support for R and Python. This allows users to immediately work with the data without having to install tools or download data, but as well to design, debug and test applications on the platform. - A prototype of jupyter Notebooks is available with some examples worked out to show the potential of the data. Today the platform is used by several third party projects to perform R&D activities on the data, and to develop/host data analysis toolboxes. In parallel the platform is further improved and extended. From the MEP PROBA-V, access to Sentinel-2 and landsat data will

  2. Exploiting Untapped Information Resources in Earth Science

    NASA Astrophysics Data System (ADS)

    Ramachandran, R.; Fox, P. A.; Kempler, S.; Maskey, M.

    2015-12-01

    One of the continuing challenges in any Earth science investigation is the amount of time and effort required for data preparation before analysis can begin. Current Earth science data and information systems have their own shortcomings. For example, the current data search systems are designed with the assumption that researchers find data primarily by metadata searches on instrument or geophysical keywords, assuming that users have sufficient knowledge of the domain vocabulary to be able to effectively utilize the search catalogs. These systems lack support for new or interdisciplinary researchers who may be unfamiliar with the domain vocabulary or the breadth of relevant data available. There is clearly a need to innovate and evolve current data and information systems in order to improve data discovery and exploration capabilities to substantially reduce the data preparation time and effort. We assert that Earth science metadata assets are dark resources, information resources that organizations collect, process, and store for regular business or operational activities but fail to utilize for other purposes. The challenge for any organization is to recognize, identify and effectively utilize the dark data stores in their institutional repositories to better serve their stakeholders. NASA Earth science metadata catalogs contain dark resources consisting of structured information, free form descriptions of data and pre-generated images. With the addition of emerging semantic technologies, such catalogs can be fully utilized beyond their original design intent of supporting current search functionality. In this presentation, we will describe our approach of exploiting these information resources to provide novel data discovery and exploration pathways to science and education communities

  3. Exploitation of Parallelism in Climate Models

    SciTech Connect

    Baer, F.; Tribbia, J.J.; Williamson, D.L.

    1999-03-01

    The US Department of Energy (DOE), through its CHAMMP initiative, hopes to develop the capability to make meaningful regional climate forecasts on time scales exceeding a decade, such capability to be based on numerical prediction type models. We propose research to contribute to each of the specific items enumerated in the CHAMMP announcement (Notice 91-3); i.e., to consider theoretical limits to prediction of climate and climate change on appropriate time scales, to develop new mathematical techniques to utilize massively parallel processors (MPP), to actually utilize MPPs as a research tool, and to develop improved representations of some processes essential to climate prediction. In particular, our goals are to: (1) Reconfigure the prediction equations such that the time iteration process can be compressed by use of MMP architecture, and to develop appropriate algorithms. (2) Develop local subgrid scale models which can provide time and space dependent parameterization for a state- of-the-art climate model to minimize the scale resolution necessary for a climate model, and to utilize MPP capability to simultaneously integrate those subgrid models and their statistics. (3) Capitalize on the MPP architecture to study the inherent ensemble nature of the climate problem. By careful choice of initial states, many realizations of the climate system can be determined concurrently and more realistic assessments of the climate prediction can be made in a realistic time frame. To explore these initiatives, we will exploit all available computing technology, and in particular MPP machines. We anticipate that significant improvements in modeling of climate on the decadal and longer time scales for regional space scales will result from our efforts.

  4. Microrheological Coagulation Assay Exploiting Micromechanical Resonators.

    PubMed

    Padovani, Francesco; Duffy, James; Hegner, Martin

    2017-01-03

    Rheological measurements in biological liquids yield insights into homeostasis and provide information on important molecular processes that affect fluidity. We present a fully automated cantilever-based method for highly precise and sensitive measurements of microliter sample volumes of human blood plasma coagulation (0.009 cP for viscosity range 0.5-3 cP and 0.0012 g/cm(3) for density range 0.9-1.1 g/cm(3)). Microcantilever arrays are driven by a piezoelectric element, and resonance frequencies and quality factors of sensors that change over time are evaluated. A highly accurate approximation of the hydrodynamic function is introduced that correlates resonance frequency and quality factor of cantilever beams immersed in a fluid to the viscosity and density of that fluid. The theoretical model was validated using glycerol reference solutions. We present a surface functionalization protocol that allows minimization of unspecific protein adsorption onto cantilevers. Adsorption leads to measurement distortions and incorrect estimation of the fluid parameters (viscosity and density). Two hydrophilic terminated self-assembled monolayers (SAMs) sensor surfaces are compared to a hydrophobic terminated SAM coating. As expected, the hydrophobic modified surfaces induced the highest mass adsorption and could promote conformational changes of the proteins and subsequent abnormal biological activity. Finally, the activated partial thromboplastin time (aPTT) coagulation assay was performed, and the viscosity, density, and coagulation rate of human blood plasma were measured along with the standard coagulation time. The method could extend and improve current coagulation testing.

  5. Differences in susceptibility and immune responses of three-spined sticklebacks (Gasterosteus aculeatus) from lake and river ecotypes to sequential infections with the eye fluke Diplostomum pseudospathaceum

    PubMed Central

    2014-01-01

    Background The eye fluke Diplostomum pseudospathaceum is a frequent parasite of many fresh-water fish species, among those three-spined sticklebacks, particularly in lakes with lymnaeid snails, its first intermediate hosts. Cercariae released from host-snails, penetrate the skin of their fish hosts and within 24 h migrate to the immunologically inert eye lenses. Thus, individual D. pseudospathaceum are exposed to the fish immune system only for a short time, suggesting that only innate immunity can be active against the parasite. However, in nature sticklebacks are exposed to D. pseudospathaceum repeatedly since snails are shedding cercariae from late spring to autumn. Therefore, acquired immunity after initial infection would be advantageous against subsequent parasite encounters. Methods We investigated if sticklebacks originating from a lake with high and from a river with low prevalence of D. pseudospathaceum differ in susceptibility to repeated exposure to the parasite. We compared infection success and immune functions in laboratory-bred sticklebacks from both habitats in naïve fish with fish that had been pre-exposed to eye flukes. Head kidney leukocytes (HKL) from experimental sticklebacks were investigated for respiratory burst activity and the proliferation of lymphocytes and monocytes 1.5, 5 and 15 days after infection. Results Lake sticklebacks were less susceptible than river sticklebacks, however, in both populations pre-exposure led to a similar relative reduction in infection success. The respiratory burst activity was higher with HKL from lake sticklebacks and was up-regulated in pre-exposed fish but dropped 1.5d after an additional exposure, suggesting that activation of phagocytic cells is crucial for the defense against D. pseudospathaceum. Changes in lymphocyte proliferation were only detectable 1.5d after the last exposure in lake sticklebacks, but not 5 and 15d post exposure, indicating that a lymphocyte mediated acquired immune response

  6. Prevalence of Liver Fluke (Fasciola hepatica) in Wild Red Deer (Cervus elaphus): Coproantigen ELISA Is a Practicable Alternative to Faecal Egg Counting for Surveillance in Remote Populations.

    PubMed

    French, Andrew S; Zadoks, Ruth N; Skuce, Philip J; Mitchell, Gillian; Gordon-Gibbs, Danielle K; Craine, Alexandra; Shaw, David; Gibb, Stuart W; Taggart, Mark A

    2016-01-01

    Red deer (Cervus elaphus) are hosts of liver fluke (Fasciola hepatica); yet, prevalence is rarely quantified in wild populations. Testing fresh samples from remote regions by faecal examination (FE) can be logistically challenging; hence, we appraise frozen storage and the use of a coproantigen ELISA (cELISA) for F. hepatica surveillance. We also present cELISA surveillance data for red deer from the Highlands of Scotland. Diagnoses in faecal samples (207 frozen, 146 fresh) were compared using a cELISA and by FE. For each storage method (frozen or fresh), agreement between the two diagnostics was estimated at individual and population levels, where population prevalence was stratified into cohorts (e.g., by sampling location). To approximate sensitivity and specificity, 65 post-slaughter whole liver examinations were used as a reference. At the individual level, FE and cELISA diagnoses agreed moderately (κfrozen = 0.46; κfresh = 0.51), a likely reflection of their underlying principles. At the population level, FE and cELISA cohort prevalence correlated strongly (Pearson's R = 0.89, p < 0.0001), reflecting good agreement on relative differences between cohort prevalence. In frozen samples, prevalence by cELISA exceeded FE overall (42.8% vs. 25.8%) and in 9/12 cohorts, alluding to differences in sensitivity; though, in fresh samples, no significant difference was found. In 959 deer tested by cELISA across the Scottish Highlands, infection prevalence ranged from 9.6% to 53% by sampling location. We highlight two key advantages of cELISA over FE: i) the ability to store samples long term (frozen) without apparent loss in diagnostic power; and ii) reduced labour and the ability to process large batches. Further evaluation of cELISA sensitivity in red deer, where a range of fluke burdens can be obtained, is desirable. In the interim, the cELISA is a practicable diagnostic for F. hepatica surveillance in red deer, and its application here has revealed considerable

  7. Prevalence of Liver Fluke (Fasciola hepatica) in Wild Red Deer (Cervus elaphus): Coproantigen ELISA Is a Practicable Alternative to Faecal Egg Counting for Surveillance in Remote Populations

    PubMed Central

    French, Andrew S.; Zadoks, Ruth N.; Skuce, Philip J.; Mitchell, Gillian; Gordon-Gibbs, Danielle K.; Craine, Alexandra; Shaw, David; Gibb, Stuart W.; Taggart, Mark A.

    2016-01-01

    Red deer (Cervus elaphus) are hosts of liver fluke (Fasciola hepatica); yet, prevalence is rarely quantified in wild populations. Testing fresh samples from remote regions by faecal examination (FE) can be logistically challenging; hence, we appraise frozen storage and the use of a coproantigen ELISA (cELISA) for F. hepatica surveillance. We also present cELISA surveillance data for red deer from the Highlands of Scotland. Diagnoses in faecal samples (207 frozen, 146 fresh) were compared using a cELISA and by FE. For each storage method (frozen or fresh), agreement between the two diagnostics was estimated at individual and population levels, where population prevalence was stratified into cohorts (e.g., by sampling location). To approximate sensitivity and specificity, 65 post-slaughter whole liver examinations were used as a reference. At the individual level, FE and cELISA diagnoses agreed moderately (κfrozen = 0.46; κfresh = 0.51), a likely reflection of their underlying principles. At the population level, FE and cELISA cohort prevalence correlated strongly (Pearson’s R = 0.89, p < 0.0001), reflecting good agreement on relative differences between cohort prevalence. In frozen samples, prevalence by cELISA exceeded FE overall (42.8% vs. 25.8%) and in 9/12 cohorts, alluding to differences in sensitivity; though, in fresh samples, no significant difference was found. In 959 deer tested by cELISA across the Scottish Highlands, infection prevalence ranged from 9.6% to 53% by sampling location. We highlight two key advantages of cELISA over FE: i) the ability to store samples long term (frozen) without apparent loss in diagnostic power; and ii) reduced labour and the ability to process large batches. Further evaluation of cELISA sensitivity in red deer, where a range of fluke burdens can be obtained, is desirable. In the interim, the cELISA is a practicable diagnostic for F. hepatica surveillance in red deer, and its application here has revealed considerable

  8. Beyond Fair Benefits: Reconsidering Exploitation Arguments Against Organ Markets.

    PubMed

    Koplin, Julian J

    2017-02-04

    One common objection to establishing regulated live donor organ markets is that such markets would be exploitative. Perhaps surprisingly, exploitation arguments against organ markets have been widely rejected in the philosophical literature on the subject. It is often argued that concerns about exploitation should be addressed by increasing the price paid to organ sellers, not by banning the trade outright. I argue that this analysis rests on a particular conception of exploitation (which I refer to as 'fair benefits' exploitation), and outline two additional ways that the charge of exploitation can be understood (which I discuss in terms of 'fair process' exploitation and complicity in injustice). I argue that while increasing payments to organ sellers may mitigate or eliminate fair benefits exploitation, such measures will not necessarily address fair process exploitation or complicity in injustice. I further argue that each of these three forms of wrongdoing is relevant to the ethics of paid living organ donation, as well as the design of public policy more generally.

  9. Plasmodium vivax Pre-Erythrocytic–Stage Antigen Discovery: Exploiting Naturally Acquired Humoral Responses

    PubMed Central

    Molina, Douglas M.; Finney, Olivia C.; Arevalo-Herrera, Myriam; Herrera, Socrates; Felgner, Philip L.; Gardner, Malcolm J.; Liang, Xiaowu; Wang, Ruobing

    2012-01-01

    The development of pre-erythrocytic Plasmodium vivax vaccines is hindered by the lack of in vitro culture systems or experimental rodent models. To help bypass these roadblocks, we exploited the fact that naturally exposed Fy− individuals who lack the Duffy blood antigen (Fy) receptor are less likely to develop blood-stage infections; therefore, they preferentially develop immune responses to pre-erythrocytic–stage parasites, whereas Fy+ individuals experience both liver- and blood-stage infections and develop immune responses to both pre-erythrocytic and erythrocytic parasites. We screened 60 endemic sera from P. vivax-exposed Fy+ or Fy− donors against a protein microarray containing 91 P. vivax proteins with P. falciparum orthologs that were up-regulated in sporozoites. Antibodies against 10 P. vivax antigens were identified in sera from P. vivax-exposed individuals but not unexposed controls. This technology has promising implications in the discovery of potential vaccine candidates against P. vivax malaria. PMID:22826492

  10. Artificial blood.

    PubMed

    Sarkar, Suman

    2008-07-01

    Artificial blood is a product made to act as a substitute for red blood cells. While true blood serves many different functions, artificial blood is designed for the sole purpose of transporting oxygen and carbon dioxide throughout the body. Depending on the type of artificial blood, it can be produced in different ways using synthetic production, chemical isolation, or recombinant biochemical technology. Development of the first blood substitutes dates back to the early 1600s, and the search for the ideal blood substitute continues. Various manufacturers have products in clinical trials; however, no truly safe and effective artificial blood product is currently marketed. It is anticipated that when an artificial blood product is available, it will have annual sales of over $7.6 billion in the United States alone.

  11. Nanostructures Exploit Hybrid-Polariton Resonances

    NASA Technical Reports Server (NTRS)

    Anderson, Mark

    2008-01-01

    Nanostructured devices that exploit the hybrid-polariton resonances arising from coupling among photons, phonons, and plasmons are subjects of research directed toward the development of infrared-spectroscopic sensors for measuring extremely small quantities of molecules of interest. The spectroscopic techniques in question are surface enhanced Raman scattering (SERS) and surface enhanced infrared absorption (SEIRA). An important intermediate goal of this research is to increase the sensitivity achievable by these techniques. The basic idea of the approach being followed in this research is to engineer nanostructured devices and thereby engineer their hybrid-polariton resonances to concentrate infrared radiation incident upon their surfaces in such a manner as to increase the absorption of the radiation for SEIRA and measure the frequency shifts of surface vibrational modes. The underlying hybrid-polariton-resonance concept is best described by reference to experimental devices that have been built and tested to demonstrate the concept. The nanostructure of each such device includes a matrix of silicon carbide particles of approximately 1 micron in diameter that are supported on a potassium bromide (KBr) or poly(tetrafluoroethylene) [PTFE] window. These grains are sputter-coated with gold grains of 40-nm size (see figure). From the perspective of classical electrodynamics, in this nanostructure, that includes a particulate or otherwise rough surface, the electric-field portion of an incident electromagnetic field becomes concentrated on the particles when optical resonance conditions are met. Going beyond the perspective of classical electrodynamics, it can be seen that when the resonance frequencies of surface phonons and surface plasmons overlap, the coupling of the resonances gives rise to an enhanced radiation-absorption or -scattering mechanism. The sizes, shapes, and aggregation of the particles determine the frequencies of the resonances. Hence, the task of

  12. Simulation of subsea gas hydrate exploitation

    NASA Astrophysics Data System (ADS)

    Janicki, Georg; Schlüter, Stefan; Hennig, Torsten; Deerberg, Görge

    2014-05-01

    The recovery of methane from gas hydrate layers that have been detected in several subsea sediments and permafrost regions around the world is a promising perspective to overcome future shortages in natural gas supply. Being aware that conventional natural gas resources are limited, research is going on to develop technologies for the production of natural gas from such new sources. Thus various research programs have started since the early 1990s in Japan, USA, Canada, India, and Germany to investigate hydrate deposits and develop required technologies. In recent years, intensive research has focussed on the capture and storage of CO2 from combustion processes to reduce climate impact. While different natural or man-made reservoirs like deep aquifers, exhausted oil and gas deposits or other geological formations are considered to store gaseous or liquid CO2, the storage of CO2 as hydrate in former methane hydrate fields is another promising alternative. Due to beneficial stability conditions, methane recovery may be well combined with CO2 storage in the form of hydrates. Regarding technological implementation many problems have to be overcome. Especially mixing, heat and mass transfer in the reservoir are limiting factors causing very long process times. Within the scope of the German research project »SUGAR« different technological approaches for the optimized exploitation of gas hydrate deposits are evaluated and compared by means of dynamic system simulations and analysis. Detailed mathematical models for the most relevant chemical and physical processes are developed. The basic mechanisms of gas hydrate formation/dissociation and heat and mass transport in porous media are considered and implemented into simulation programs. Simulations based on geological field data have been carried out. The studies focus on the potential of gas production from turbidites and their fitness for CO2 storage. The effects occurring during gas production and CO2 storage within

  13. Simulated population responses of common carp to commercial exploitation

    SciTech Connect

    Weber, Michael J.; Hennen, Matthew J.; Brown, Michael L.

    2011-12-01

    Common carp Cyprinus carpio is a widespread invasive species that can become highly abundant and impose deleterious ecosystem effects. Thus, aquatic resource managers are interested in controlling common carp populations. Control of invasive common carp populations is difficult, due in part to the inherent uncertainty of how populations respond to exploitation. To understand how common carp populations respond to exploitation, we evaluated common carp population dynamics (recruitment, growth, and mortality) in three natural lakes in eastern South Dakota. Common carp exhibited similar population dynamics across these three systems that were characterized by consistent recruitment (ages 3 to 15 years present), fast growth (K = 0.37 to 0.59), and low mortality (A = 1 to 7%). We then modeled the effects of commercial exploitation on size structure, abundance, and egg production to determine its utility as a management tool to control populations. All three populations responded similarly to exploitation simulations with a 575-mm length restriction, representing commercial gear selectivity. Simulated common carp size structure modestly declined (9 to 37%) in all simulations. Abundance of common carp declined dramatically (28 to 56%) at low levels of exploitation (0 to 20%) but exploitation >40% had little additive effect and populations were only reduced by 49 to 79% despite high exploitation (>90%). Maximum lifetime egg production was reduced from 77 to 89% at a moderate level of exploitation (40%), indicating the potential for recruitment overfishing. Exploitation further reduced common carp size structure, abundance, and egg production when simulations were not size selective. Our results provide insights to how common carp populations may respond to exploitation. Although commercial exploitation may be able to partially control populations, an integrated removal approach that removes all sizes of common carp has a greater chance of controlling population abundance

  14. Exploiting for medical and biological applications

    NASA Astrophysics Data System (ADS)

    Giano, Michael C.

    Biotherapeutics are an emerging class of drug composed of molecules ranging in sizes from peptides to large proteins. Due to their poor stability and mucosal membrane permeability, biotherapeutics are administered by a parenteral method (i.e., syringe, intravenous or intramuscular). Therapeutics delivered systemically often experience short half-lives. While, local administration may involve invasive surgical procedures and suffer from poor retention at the site of application. To compensate, the patient receives frequent doses of highly concentrated therapeutic. Unfortunately, the off-target side effects and discomfort associated with multiple injections results in poor patient compliance. Therefore, new delivery methods which can improve therapeutic retention, reduce the frequency of administration and may aid in decreasing the off-target side effects is a necessity. Hydrogels are a class of biomaterials that are gaining interests for tissue engineering and drug delivery applications. Hydrogel materials are defined as porous, 3-dimensional networks that are primarily composed of water. Generally, they are mechanically rigid, cytocompatible and easily chemically functionalized. Collectively, these properties make hydrogels fantastic candidates to perform as drug delivery depots. Current hydrogel delivery systems physically entrap the target therapeutic which is then subsequently released over time at the site of administration. The swelling and degradation of the material effect the diffusion of the therapy from the hydrogel, and therefore should be controlled. Although these strategies provide some regulation over therapeutic release, full control of the delivery is not achieved. Newer approaches are focused on designing hydrogels that exploit known interactions, covalently attach the therapy or respond to an external stimulus in an effort to gain improved control over the therapy's release. Unfortunately, the biotherapeutic is typically required to be chemically

  15. Genetic differentiation in eastern European and western Asian populations of the liver fluke, Fasciola hepatica, as revealed by mitochondrial nad1 and cox1 genes.

    PubMed

    Semyenova, Seraphima K; Morozova, Elena V; Chrisanfova, Galina G; Gorokhov, Vladimir V; Arkhipov, Ivan A; Moskvin, Alexander S; Movsessyan, Sergey O; Ryskov, Alexei P

    2006-06-01

    Partial sequences of mitochondrial genes nad1 (316 bp) and cox1 (429 bp) were analyzed to estimate the variability of the liver fluke samples collected in 20 localities in Russia, Belarus, Ukraine, Bulgaria, Armenia, Azerbaijan, Georgia, Turkey, Turkmenistan, and China. The sequences had 4.1% (nad1) and 2.3% (cox1) of variable sites, and 13 and 10 haplotypes were identified among nad1 and cox1 genes, respectively. Spatial analysis of genetic and nucleotide diversity indicated little or no structuring of genetic variation between hosts or regions. The analysis of distribution of both separate and combined (nad1 + cox1) haplotypes revealed the existence of 2 well-defined lineages with 2 main haplotypes and a number of shared divergent haplotypes. Our study showed that the first lineage included the main N1-C1 haplotype, which was found in Australia, China, Georgia, Turkey, Armenia, Azerbaijan, and in all European populations (from Russia, Belarus, Ukraine, Bulgaria). The second lineage was found in all European populations and in populations from Armenia and Azerbaijan. It was suggested that one of the lineages (I) has an Asian origin. The possible source of mtDNA variability and associations between lineage divergence of parasite and its definitive hosts (cattle and sheep) are discussed.

  16. Immune responses in rats and sheep induced by a DNA vaccine containing the phosphoglycerate kinase gene of Fasciola hepatica and liver fluke infection.

    PubMed

    Wesołowska, Agnieszka; Zawistowska-Deniziak, Anna; Norbury, Luke J; Wilkowski, Przemysław; Januszkiewicz, Kamil; Pyziel, Anna M; Zygner, Wojciech; Wędrychowicz, Halina

    2016-03-01

    Immune responses of rats and sheep following vaccination with cDNA encoding phosphoglycerate kinase of Fasciola hepatica (cDNA-FhPGK/pCMV) and F. hepatica infection were investigated in the present study. cDNA-FhPGK/pCMV vaccinated female Sprague-Dawley rats were better protected by vaccination than their male counterparts - 48% reduction in fluke burden for females and no protection for males when compared with appropriate infection control groups. Moreover, male rats developed marked leukocytosis during the study with higher neutrophil, eosinophil and monocyte responses than females. Additionally, dynamics of eosinophil and monocyte responses varied between sexes. Increased titres of anti-FhPGK IgG1 and IgG2a correlated with the protective effect of vaccination that was observed among female rats. In the case of male sheep, no differences in worm burdens and in the course of the immune response were observed following vaccination. Titres of specific antibodies detected were low, and cellular responses were not significant. Apparently, sheep immune responses induced by cDNA-FhPGK/pCMV vaccination are not effective at controlling F. hepatica infection. Poor immunogenicity of DNA vaccines in large animals is still a major obstacle of this technology that has to be overcome.

  17. Influence of levamisole and Freund's adjuvant on mouse immunisation with antigens of adults of the liver fluke Fasciola hepatica Linnaeus, 1758.

    PubMed

    Gutierrez-Sanchez, Maria de Los Angeles; Luna-Herrera, Julieta; Trejo-Castro, Lauro; Montenegro-Cristino, Natividad; Almanza-Gonzalez, Alfredo; Escobar-Gutierrez, Alejandro; de la Rosa-Arana, Jorge Luis

    2015-08-28

    We have studied the influence of both levamisole (AL) and Freund's adjuvant (AF) on the immunisation of mice with the secretory antigens of adults of the liver fluke Fasciola hepatica Linnaeus, 1758. Total IgG antibodies were detected in all groups where the F. hepatica antigen was administered, been levels of IgG1 increased respect to IgG2a antibodies. During immunisation, IL-4 and IFN-γ were only detected in AL and AF groups, but after infection, IL-4 boosted in all groups. IFN-γ increased two fold in AF and AL groups compared to the saline solution (AS) group. Worm recovering was of 32-35% in groups administered without antigen whereas in AS, AL and AF groups recovering was of 25%, 12% and 8%, respectively. Macroscopical lesions in the liver were scarce in AL and AF groups. Our data suggest that immunisation of mice with antigens of F. hepatica enhances the immune response avoiding both liver damage and worm establishment after challenge infection. The murine model of fasciolosis has appeared to be useful to elucidate the mechanism by which the parasite modulates immune responses toward a Th2 type but also the development of Th1 type-inducing vaccines.

  18. Identification and potential use of a soluble tumor antigen for the detection of liver-fluke-associated cholangiocarcinoma induced in a hamster model.

    PubMed

    Prempracha, N; Tengchaisri, T; Chawengkirttikul, R; Boonpucknavig, S; Thamavit, W; Duongchawee, G; Sirisinha, S

    1994-06-01

    A liver-fluke-associated cholangiocarcinoma (CCA), comparable to that occurring in humans, was induced by exposing Opisthorchis viverrini-infected hamsters to dimethylnitrosamine (DMN). Tumor masses were removed and histopathologically identified, then one portion was extracted for antigens used in the production of monoclonal antibodies (MAbs). The remaining portions were used to establish CCA cell lines. The antigens produced and secreted by these cell lines, as well as those originally present in the tissue extracts, possessed a 200-kDa glycoprotein that appeared to be immunologically distinct from other tumor markers. A specific MAb called 6E5 was used to set up a sandwich ELISA for the quantification of this antigen in the serum and bile of tumor-bearing animals. The assay system was sensitive enough to detect the antigen at concentrations below 10 ng/ml. The serum and biliary levels of this antigen were markedly elevated in animals with progressive tumors when compared with untreated controls. The serum taken serially from each animal that subsequently developed CCA showed a gradual but significant elevation of the antigen as carcinogenesis progressed. A few isolated animals exhibited a slight elevation of the antigen at a time as early as the end of DMN treatment, when the CCA should not yet have developed, judging from microscopic examination. The data from this animal model suggested that the CCA-associated soluble antigen defined by MAb 6E5 was a useful marker for the detection of tumors at an early stage of development.

  19. Blood Basics

    MedlinePlus

    ... woman has about nine pints. Jump To: The Components of Blood and Their Importance Many people have ... and treatment. back to top Plasma The liquid component of blood is called plasma, a mixture of ...

  20. Blood Clots

    MedlinePlus

    ... or prevent blood clots from dissolving properly. Risk factors for excessive blood clotting include Certain genetic disorders Atherosclerosis Diabetes Atrial fibrillation Overweight, obesity, and metabolic syndrome Some medicines Smoking deep vein ...

  1. Blood Types

    MedlinePlus

    ... the wrong blood type, the antibodies immediately set out to destroy the invading cells. This aggressive, whole-body response can give someone a fever, chills, and low blood pressure. It can even lead ...

  2. Blood Typing

    MedlinePlus

    ... this page helpful? Also known as: Blood Group; Rh Factor Formal name: ABO Group and Rh Type Related ... mother's and baby's ABO blood groups, not the Rh factor. However, ABO grouping cannot be used to predict ...

  3. Blood Donation

    MedlinePlus

    ... as A, B, AB or O — and your Rh factor. The Rh factor refers to the presence or absence of a ... information is important because your blood type and Rh factor must be compatible with the blood type and ...

  4. Early Sexual Exploitation as an Influence in Prostitution.

    ERIC Educational Resources Information Center

    Silbert, Mimi H.; Pines, Ayala M.

    1983-01-01

    Surveyed 200 female street prostitutes to determine whether they were sexually exploited during childhood. Results showed 60 percent of the subjects were sexually exploited. The few girls who discussed their abuse with others were met with shame and most often inaction. Only 10 percent were abused by strangers. (JAC)

  5. A Descriptive Study on Sexually Exploited Children in Residential Treatment

    ERIC Educational Resources Information Center

    Twill, Sarah E.; Green, Denise M.; Traylor, Amy

    2010-01-01

    Sexual exploitation and prostitution of children and adolescents is a multibillion dollar industry in the United States (Estes and Weiner in "Medical, legal & social science aspects of child sexual exploitation: A comprehensive review of pornography, prostitution, and internet crimes, vol I," G.W. Medical Publishing, Inc, St Louis,…

  6. Self-Report Measure of Financial Exploitation of Older Adults

    ERIC Educational Resources Information Center

    Conrad, Kendon J.; Iris, Madelyn; Ridings, John W.; Langley, Kate; Wilber, Kathleen H.

    2010-01-01

    Purpose: This study was designed to improve the measurement of financial exploitation (FE) by testing psychometric properties of the older adult financial exploitation measure (OAFEM), a client self-report instrument. Design and Methods: Rasch item response theory and traditional validation approaches were used. Questionnaires were administered by…

  7. A Descriptive Study on Sexually Exploited Children in Residential Treatment

    ERIC Educational Resources Information Center

    Twill, Sarah E.; Green, Denise M.; Traylor, Amy

    2010-01-01

    Sexual exploitation and prostitution of children and adolescents is a multibillion dollar industry in the United States (Estes and Weiner in "Medical, legal & social science aspects of child sexual exploitation: A comprehensive review of pornography, prostitution, and internet crimes, vol I," G.W. Medical Publishing, Inc, St Louis,…

  8. Artificial Blood for Dogs

    PubMed Central

    Yamada, Kana; Yokomaku, Kyoko; Kureishi, Moeka; Akiyama, Motofusa; Kihira, Kiyohito; Komatsu, Teruyuki

    2016-01-01

    There is no blood bank for pet animals. Consequently, veterinarians themselves must obtain “blood” for transfusion therapy. Among the blood components, serum albumin and red blood cells (RBCs) are particularly important to save lives. This paper reports the synthesis, structure, and properties of artificial blood for the exclusive use of dogs. First, recombinant canine serum albumin (rCSA) was produced using genetic engineering with Pichia yeast. The proteins showed identical features to those of the native CSA derived from canine plasma. Furthermore, we ascertained the crystal structure of rCSA at 3.2 Å resolution. Pure rCSA can be used widely for numerous clinical and pharmaceutical applications. Second, hemoglobin wrapped covalently with rCSA, hemoglobin–albumin cluster (Hb-rCSA3), was synthesized as an artificial O2-carrier for the RBC substitute. This cluster possesses satisfactorily negative surface net charge (pI = 4.7), which supports enfolding of the Hb core by rCSA shells. The anti-CSA antibody recognized the rCSA exterior quantitatively. The O2-binding affinity was high (P50 = 9 Torr) compared to that of the native Hb. The Hb-rCSA3 cluster is anticipated for use as an alternative material for RBC transfusion, and as an O2 therapeutic reagent that can be exploited in various veterinary medicine situations. PMID:27830776

  9. Blood Conservation.

    PubMed

    Martin, Jeremiah T; Ferraris, Victor A

    2015-01-01

    Patient blood management requires multi-modality and multidisciplinary collaboration to identify patients who are at increased risk of requiring blood transfusion and therefore decrease exposure to blood products. Transfusion is associated with poor postoperative outcomes, and guidelines exist to minimize transfusion requirements. This review highlights recent studies and efforts to apply patient blood management across disease processes and health care systems. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. The Intersection of Financial Exploitation and Financial Capacity

    PubMed Central

    Lichtenberg, P.A.

    2016-01-01

    Research in the past decade has documented that financial exploitation of older adults has become a major problem and Psychology is only recently increasing its presence in efforts to reduce exploitation. During the same time period, Psychology has been a leader in setting best practices for the assessment of diminished capacity in older adults culminating in the 2008 ABA/APA joint publication on a handbook for psychologists. Assessment of financial decision making capacity is often the cornerstone assessment needed in cases of financial exploitation. This paper will examine the intersection of financial exploitation and decision making capacity; introduce a new conceptual model and new tools for both the investigation and prevention of financial exploitation. PMID:27159438

  11. [Ecotourism exploitation model in Bita Lake Natural Reserve of Yunnan].

    PubMed

    Yang, G; Wang, Y; Zhong, L

    2000-12-01

    Bita lake provincial natural reserve is located in Shangri-La region of North-western Yunnan, and was set as a demonstrating area for ecotourism exploitation in 1998. After a year's exploitation construction and half a year's operation as a branch of the 99' Kunming International Horticulture Exposition to accept tourists, it was proved that the ecotourism demonstrating area attained four integrated functions of ecotourism, i.e., tourism, protection, poverty clearing and environment education. Five exploitation and management models including function zoned exploitation model, featured tourism communication model signs system designing model, local Tibetan family reception model and environmental monitoring model, were also successful, which were demonstrated and spreaded to the whole province. Bita lake provincial natural reserve could be a good sample for the ecotourism exploitation natural reserves of the whole country.

  12. Exploit and ignore the consequences: A mother of planetary issues

    NASA Astrophysics Data System (ADS)

    Moustafa, K.

    2016-07-01

    Many environmental and planetary issues are due to an exploitation strategy based on exploit, consume and ignore the consequences. As many natural and environmental resources are limited in time and space, such exploitation approach causes important damages on earth, in the sea and maybe soon in the space. To sustain conditions under which humans and other living species can coexist in productive and dynamic harmony with their environments, terrestrial and space exploration programs may need to be based on 'scrutinize the consequences, prepare adequate solutions and then, only then, exploit'. Otherwise, the exploitation of planetary resources may put the environmental stability and sustainability at a higher risk than it is currently predicted. (C) 2016 Elsevier B.V. All rights reserved.

  13. Blood money.

    PubMed

    Cohen, S B

    2000-11-01

    Foetal blood contains cells that can regenerate all the cellular elements of blood and the immune system (stem cells). This blood can be obtained from the placenta without any harm to mother or baby and is currently used as a successful alternative to bone marrow for paediatric transplantation. Recently, it has been suggested that this blood can be put in storage and used (if needed) for the child that the blood originally came from. This has prompted a commercial interest, leading to both financial and ethical concerns.

  14. Uncertainty of exploitation estimates made from tag returns

    USGS Publications Warehouse

    Miranda, L.E.; Brock, R.E.; Dorr, B.S.

    2002-01-01

    Over 6,000 crappies Pomoxis spp. were tagged in five water bodies to estimate exploitation rates by anglers. Exploitation rates were computed as the percentage of tags returned after adjustment for three sources of uncertainty: postrelease mortality due to the tagging process, tag loss, and the reporting rate of tagged fish. Confidence intervals around exploitation rates were estimated by resampling from the probability distributions of tagging mortality, tag loss, and reporting rate. Estimates of exploitation rates ranged from 17% to 54% among the five study systems. Uncertainty around estimates of tagging mortality, tag loss, and reporting resulted in 90% confidence intervals around the median exploitation rate as narrow as 15 percentage points and as broad as 46 percentage points. The greatest source of estimation error was uncertainty about tag reporting. Because the large investments required by tagging and reward operations produce imprecise estimates of the exploitation rate, it may be worth considering other approaches to estimating it or simply circumventing the exploitation question altogether.

  15. Rationalising predictors of child sexual exploitation and sex-trading.

    PubMed

    Klatt, Thimna; Cavner, Della; Egan, Vincent

    2014-02-01

    Although there is evidence for specific risk factors leading to child sexual exploitation and prostitution, these influences overlap and have rarely been examined concurrently. The present study examined case files for 175 young persons who attended a voluntary organization in Leicester, United Kingdom, which supports people who are sexually exploited or at risk of sexual exploitation. Based on the case files, the presence or absence of known risk factors for becoming a sex worker was coded. Data were analyzed using t-test, logistic regression, and smallest space analysis. Users of the voluntary organization's services who had been sexually exploited exhibited a significantly greater number of risk factors than service users who had not been victims of sexual exploitation. The logistic regression produced a significant model fit. However, of the 14 potential predictors--many of which were associated with each other--only four variables significantly predicted actual sexual exploitation: running away, poverty, drug and/or alcohol use, and having friends or family members in prostitution. Surprisingly, running away was found to significantly decrease the odds of becoming involved in sexual exploitation. Smallest space analysis of the data revealed 5 clusters of risk factors. Two of the clusters, which reflected a desperation and need construct and immature or out-of-control lifestyles, were significantly associated with sexual exploitation. Our research suggests that some risk factors (e.g. physical and emotional abuse, early delinquency, and homelessness) for becoming involved in sexual exploitation are common but are part of the problematic milieu of the individuals affected and not directly associated with sex trading itself. Our results also indicate that it is important to engage with the families and associates of young persons at risk of becoming (or remaining) a sex worker if one wants to reduce the numbers of persons who engage in this activity. Copyright

  16. Blood Analyzer

    NASA Technical Reports Server (NTRS)

    1992-01-01

    In the 1970's, NASA provided funding for development of an automatic blood analyzer for Skylab at the Oak Ridge National Laboratory (ORNL). ORNL devised "dynamic loading," which employed a spinning rotor to load, transfer, and analyze blood samples by centrifugal processing. A refined, commercial version of the system was produced by ABAXIS and is marketed as portable ABAXIS MiniLab MCA. Used in a doctor's office, the equipment can perform 80 to 100 chemical blood tests on a single drop of blood and report results in five minutes. Further development is anticipated.

  17. Conceptual model and map of financial exploitation of older adults.

    PubMed

    Conrad, Kendon J; Iris, Madelyn; Ridings, John W; Fairman, Kimberly P; Rosen, Abby; Wilber, Kathleen H

    2011-10-01

    This article describes the processes and outcomes of three-dimensional concept mapping to conceptualize financial exploitation of older adults. Statements were generated from a literature review and by local and national panels consisting of 16 experts in the field of financial exploitation. These statements were sorted and rated using Concept Systems software, which grouped the statements into clusters and depicted them as a map. Statements were grouped into six clusters, and ranked by the experts as follows in descending severity: (a) theft and scams, (b) financial victimization, (c) financial entitlement, (d) coercion, (e) signs of possible financial exploitation, and (f) money management difficulties. The hierarchical model can be used to identify elder financial exploitation and differentiate it from related but distinct areas of victimization. The severity hierarchy may be used to develop measures that will enable more precise screening for triage of clients into appropriate interventions.

  18. Human Factors Design Issues for Spectral Exploitation Tools

    DTIC Science & Technology

    2000-02-01

    widely accepted or utilized in the operational community. This is primarily due to sensor collection limitations, dynamic time constraints, lack of user ... experience , and limited availability of validated exploitation tools and techniques. This effort implements human factors and cognitive engineering

  19. Exploration-exploitation strategy is dependent on early experience.

    PubMed

    Humphreys, Kathryn L; Lee, Steve S; Telzer, Eva H; Gabard-Durnam, Laurel J; Goff, Bonnie; Flannery, Jessica; Tottenham, Nim

    2015-04-01

    Traditional conceptualizations of early adversity characterize behavioral outcomes as maladaptive. However, conditional adaptation theory proposes that differing behavioral phenotypes following early experience are appropriate for the expected environment (e.g., behaviors likely to result in the best outcome based on environmental expectations). In the present study, youth with (n = 46) and without (n = 91) a history of previous institutionalization completed a laboratory-based experimental paradigm in which exploration-exploitation strategy was examined, a phenotype relevant to environmental expectations. Previous institutionalization was associated with decreased exploration and increased exploitation. A strategy favoring exploration resulted in greater success in the generous task condition whereas a strategy favoring exploitation produced greater success in the restricted task condition. These results suggest that exploration-exploitation strategy may be influenced by early experience, and the resulting success of strategy choice is context dependent and in line with expectations of the future environment based on early experience. © 2015 Wiley Periodicals, Inc.

  20. A Serial of Technologies Exploiting Towards Data Share

    NASA Astrophysics Data System (ADS)

    Lin, G. H.

    2006-08-01

    One of the purposes of the Virtual Observatory is providing data share. The Solar Multi-Channel Telescope in Huairou Solar Observing Station, Beijing of China is not only used for science research but also for solar activity prediction and space environment prediction. For providing these services, we have been carrying through a serial of technologies exploiting. In this article, we will discuss the exploiting. The exploiting includes setting up WWW server, network, network safety facility, data processing software and designing international unified meta data for our speciality, etc. So far, as result of these exploiting, the initial needs have can be reached. We still have further work to implement. Such as, uploading data in real time, setting up database with query function, continuous improvement of the software, etc.

  1. RNA-Seq reveals infection-induced gene expression changes in the snail intermediate host of the carcinogenic liver fluke, Opisthorchis viverrini.

    PubMed

    Prasopdee, Sattrachai; Sotillo, Javier; Tesana, Smarn; Laha, Thewarach; Kulsantiwong, Jutharat; Nolan, Matthew J; Loukas, Alex; Cantacessi, Cinzia

    2014-03-01

    Bithynia siamensis goniomphalos is the snail intermediate host of the liver fluke, Opisthorchis viverrini, the leading cause of cholangiocarcinoma (CCA) in the Greater Mekong sub-region of Thailand. Despite the severe public health impact of Opisthorchis-induced CCA, knowledge of the molecular interactions occurring between the parasite and its snail intermediate host is scant. The examination of differences in gene expression profiling between uninfected and O. viverrini-infected B. siamensis goniomphalos could provide clues on fundamental pathways involved in the regulation of snail-parasite interplay. Using high-throughput (Illumina) sequencing and extensive bioinformatic analyses, we characterized the transcriptomes of uninfected and O. viverrini-infected B. siamensis goniomphalos. Comparative analyses of gene expression profiling allowed the identification of 7,655 differentially expressed genes (DEGs), associated to 43 distinct biological pathways, including pathways associated with immune defense mechanisms against parasites. Amongst the DEGs with immune functions, transcripts encoding distinct proteases displayed the highest down-regulation in Bithynia specimens infected by O. viverrini; conversely, transcription of genes encoding heat-shock proteins and actins was significantly up-regulated in parasite-infected snails when compared to the uninfected counterparts. The present study lays the foundation for functional studies of genes and gene products potentially involved in immune-molecular mechanisms implicated in the ability of the parasite to successfully colonize its snail intermediate host. The annotated dataset provided herein represents a ready-to-use molecular resource for the discovery of molecular pathways underlying susceptibility and resistance mechanisms of B. siamensis goniomphalos to O. viverrini and for comparative analyses with pulmonate snail intermediate hosts of other platyhelminths including schistosomes.

  2. Excretory/secretory products of the carcinogenic liver fluke are endocytosed by human cholangiocytes and drive cell proliferation and IL6 production.

    PubMed

    Chaiyadet, Sujittra; Smout, Michael; Johnson, Michael; Whitchurch, Cynthia; Turnbull, Lynne; Kaewkes, Sasithorn; Sotillo, Javier; Loukas, Alex; Sripa, Banchob

    2015-10-01

    Liver fluke infection caused by Opisthorchis viverrini remains a major public health problem in many parts of Asia including Thailand, Lao PDR, Vietnam and Cambodia, where there is a strikingly high incidence of cholangiocarcinoma (CCA - hepatic cancer of the bile duct epithelium). Among other factors, uptake of O. viverrini excretory/secretory products (OvES) by biliary epithelial cells has been postulated to be responsible for chronic inflammation and proliferation of cholangiocytes, but the mechanisms by which cells internalise O. viverrini excretory/secretory products are still unknown. Herein we incubated normal human cholangiocytes (H69), human cholangiocarcinoma cells (KKU-100, KKU-M156) and human colon cancer (Caco-2) cells with O. viverrini excretory/secretory products and analysed the effects of different endocytic inhibitors to address the mechanism of cellular uptake of ES proteins. Opisthorchis viverrini excretory/secretory products was internalised preferentially by liver cell lines, and most efficiently/rapidly by H69 cells. There was no evidence for trafficking of ES proteins to cholangiocyte organelles, and most of the fluorescence was detected in the cytoplasm. Pretreatment with clathrin inhibitors significantly reduced the uptake of O. viverrini excretory/secretory products, particularly by H69 cells. Opisthorchis viverrini excretory/secretory products induced proliferation of liver cells (H69 and CCA lines) but not intestinal (Caco-2) cells, and proliferation was blocked using inhibitors of the classical endocytic pathways (clathrin and caveolae). Opisthorchis viverrini excretory/secretory products drove IL6 secretion by H69 cells but not Caco-2 cells, and cytokine secretion was significantly reduced by endocytosis inhibitors. This the first known study to address the endocytosis of helminth ES proteins by host epithelial cells and sheds light on the pathways by which this parasite causes one of the most devastating forms of cancer in south

  3. Fasciola hepatica phenotypic characterization in Andean human endemic areas: valley versus altiplanic patterns analysed in liver flukes from sheep from Cajamarca and Mantaro, Peru.

    PubMed

    Valero, M Adela; Perez-Crespo, Ignácio; Khoubbane, Messaoud; Artigas, Patricio; Panova, Miroslava; Ortiz, Pedro; Maco, Vicente; Espinoza, José R; Mas-Coma, Santiago

    2012-03-01

    Fascioliasis is a zoonotic parasitic disease caused by Fasciola hepatica and Fasciola gigantica. Of both species, F. hepatica is the only one described in the Americas, mainly transmitted by lymnaeid snail vectors of the Galba/Fossaria group. Human fascioliasis endemic areas are mainly located in high altitude areas of Andean countries. Given the necessity to characterize F. hepatica populations involved, the phenotypic features of fasciolid adults infecting sheep present in human fascioliasis endemic areas were analysed in the Cajamarca Valley and Mantaro Valley (valley transmission patterns) and the northern Bolivian Altiplano (altiplanic transmission pattern). A computer image analysis system (CIAS) was applied on the basis of standardized measurements. The aforementioned highland populations were compared to standard lowland natural and experimental populations of European origin. Liver fluke size was studied by multivariate analyses. Two phenotypic patterns could be distinguished in F. hepatica adult size: the valley pattern (Cajamarca and Mantaro, Peru) and the altiplanic pattern (northern Altiplano, Bolivia). Results showed that the Andean valley population and European standard populations presented a phenotypic homogeneity. The Altiplano population showed a large size range with a pronouncedly lower minimum size indicating that uterus gravidity is reached at a smaller size than in valley populations. The results of this study demonstrate that there is no apparent relationship between the shape of fasciolid adults with regard to altitudinal difference or geographical origin and that allometry-free shape appears as a more stable trait than size in fasciolid species. Results are analysed in terms of intensity/crowding effect aspects and permanent/seasonal transmission characteristics.

  4. RNA-Seq Reveals Infection-Induced Gene Expression Changes in the Snail Intermediate Host of the Carcinogenic Liver Fluke, Opisthorchis viverrini

    PubMed Central

    Prasopdee, Sattrachai; Sotillo, Javier; Tesana, Smarn; Laha, Thewarach; Kulsantiwong, Jutharat; Nolan, Matthew J.

    2014-01-01

    Background Bithynia siamensis goniomphalos is the snail intermediate host of the liver fluke, Opisthorchis viverrini, the leading cause of cholangiocarcinoma (CCA) in the Greater Mekong sub-region of Thailand. Despite the severe public health impact of Opisthorchis-induced CCA, knowledge of the molecular interactions occurring between the parasite and its snail intermediate host is scant. The examination of differences in gene expression profiling between uninfected and O. viverrini-infected B. siamensis goniomphalos could provide clues on fundamental pathways involved in the regulation of snail-parasite interplay. Methodology/Principal Findings Using high-throughput (Illumina) sequencing and extensive bioinformatic analyses, we characterized the transcriptomes of uninfected and O. viverrini-infected B. siamensis goniomphalos. Comparative analyses of gene expression profiling allowed the identification of 7,655 differentially expressed genes (DEGs), associated to 43 distinct biological pathways, including pathways associated with immune defense mechanisms against parasites. Amongst the DEGs with immune functions, transcripts encoding distinct proteases displayed the highest down-regulation in Bithynia specimens infected by O. viverrini; conversely, transcription of genes encoding heat-shock proteins and actins was significantly up-regulated in parasite-infected snails when compared to the uninfected counterparts. Conclusions/Significance The present study lays the foundation for functional studies of genes and gene products potentially involved in immune-molecular mechanisms implicated in the ability of the parasite to successfully colonize its snail intermediate host. The annotated dataset provided herein represents a ready-to-use molecular resource for the discovery of molecular pathways underlying susceptibility and resistance mechanisms of B. siamensis goniomphalos to O. viverrini and for comparative analyses with pulmonate snail intermediate hosts of other

  5. De novo assembly and characterization of the transcriptome of the pancreatic fluke Eurytrema pancreaticum (trematoda: Dicrocoeliidae) using I