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1.
Am J Trop Med Hyg ; 106(1): 222-228, 2021 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-34695797

RESUMO

Here, we report for the first time the snail intermediate host for the Amphimerus liver fluke, a foodborne trematodiasis. In Ecuador, Amphimerus of the Opisthorchiidae family, infects humans, cats, and dogs, in the tropical Pacific-coast region. Opisthorchiidae comprising also Clonorchis sinensis, Opisthorchis sp., and Metorchis sp., have complex life cycles involving a definitive and two intermediate hosts. We identified morphologically and investigated the presence and prevalence of Amphimerus cercaria and DNA in freshwater snails collected in a human-amphimeriasis endemic region in Ecuador, extracted DNA from snail tissue and emerged cercariae, performed real-time polymerase chain reaction (PCR) with the newly developed primers and probe amplifying the Amphimerus ribosomal internal transcribed spacer 2 (ITS2) region, and sequenced the amplified DNA fragment. We collected 2,800 snails, characterized four species Aroapyrgus sp., Melanoides tuberculata, Biomphalaria cousini, and Aplexa marmorata, isolated three cercariae morphotypes. Of the 640 snails analyzed by qPCR, only Aroapyrgus and one of the three cercariae resulted positive, at a 15% infection prevalence. Polymerase chain reaction revealed that the Aroapyrgus snail and cercaria-morphotype-3 corresponded to Amphimerus, but not to C. sinensis, Fasciola hepatica, or Paragonimus mexicanus. The sequence of amplified DNA product matched that of human-isolated Amphimerus. This finding constitutes the first documentation that Aroapyrgus sp. is the first intermediate host for the Amphimerus sp. that infect humans in Ecuador. The ITS2-gene PCR and sequencing analysis demonstrated a high prevalence of snail infection and proved useful for detecting the infection in snails, which findings can help the establishment of suitable control programs against transmission in any endemic region of interest.


Assuntos
Gastrópodes/parasitologia , Opisthorchidae/classificação , Infecções por Trematódeos/parasitologia , Animais , DNA de Helmintos/química , DNA de Helmintos/classificação , DNA de Helmintos/isolamento & purificação , Equador , Água Doce , Gastrópodes/anatomia & histologia , Gastrópodes/classificação , Humanos , Opisthorchidae/anatomia & histologia , Opisthorchidae/genética , Opisthorchidae/isolamento & purificação , Filogenia , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Infecções por Trematódeos/transmissão
2.
J Microbiol Methods ; 187: 106258, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34082051

RESUMO

The superfamily Opisthorchioidea encompasses the families Cryptogonimidae, Opisthorchiidae and Heterophyidae. These parasites depend on the aquatic environment and include marine and freshwater species. Some species, such as Clonorchis sinensis and Opisthorchis viverrini, have a high impact on public health with millions of infected people worldwide and have thus been the object of many studies and tool developments. However, for many species, tools for identification and detection are scarce. Although morphological descriptions have been used and are still important, they are often not efficient on the immature stages of these parasites. Thus, during the past few decades, molecular approaches for parasite identification have become commonplace. These approaches are efficient, quick and reliable. Nonetheless, for some parasites of the superfamily Opisthorchioidea, reference genomic data are limited. This study reviews available genetic data and molecular tools for the identification and/or the detection of this superfamily. Molecular data on this superfamily are mostly based on mitochondrial and ribosomal gene sequence analyses, especially on the cytochrome c oxidase subunit 1 gene and internal transcribed spacer regions respectively.


Assuntos
DNA de Helmintos/genética , Parasitologia/métodos , Trematódeos/classificação , Animais , Primers do DNA , DNA de Helmintos/análise , DNA Mitocondrial/genética , DNA Ribossômico/genética , DNA Espaçador Ribossômico/análise , Complexo IV da Cadeia de Transporte de Elétrons/genética , Genes de Helmintos , Heterophyidae/classificação , Heterophyidae/genética , Heterophyidae/isolamento & purificação , Técnicas de Diagnóstico Molecular , Técnicas de Amplificação de Ácido Nucleico , Opisthorchidae/classificação , Opisthorchidae/genética , Opisthorchidae/isolamento & purificação , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Técnica de Amplificação ao Acaso de DNA Polimórfico , Trematódeos/genética , Trematódeos/isolamento & purificação
3.
PLoS Negl Trop Dis ; 14(6): e0008286, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32598382

RESUMO

Amphimerus sp. is a fluke that dwells in the biliary tracts of vertebrate definitive hosts including humans, domestic, and wild mammals in Latin America. Opisthorchiid liver infections are rarely studied in the Americas confirming its status as a neglected tropical disease. In Ecuador, small trematode eggs were reported in human cases from the province of Manabí in 1949, and recently, Amphimerus sp. adults were recovered from human and reservoir hosts in the province of Esmeraldas. Due to the lack of research on the infectious sources of Amphimerus sp. in the continent, we have developed a series of epidemiological studies with parasitological and molecular techniques to elucidate the endemicity of opisthorchiid fluke infections. We developed a cross-sectional study in three communities at Pedro Pablo Gómez parish in the province of Manabí, Ecuador. We examined a total of 176 fecal samples to detect opisthorchiid eggs, and four fish species to find opisthorchiid metacercariae. To study adult worms, we treated and purged seven patients in a family and dissected the livers of a dog and a cat infected. We observed morphological features of adults and metacercariae and used polymerase chain reaction with restricted fragment length polymorphism (PCR-RFLP) and DNA sequencing of a section of the ITS2 gene for identification. Small trematode eggs were detected in 63 (35.8%) out of 176 fecal samples of residents in the three study sites. Adult opisthorchiid flukes were recovered from human patients, a dog and a cat, and they were morphologically and molecularly identified as Amphimerus sp. Opisthorchiid metacercariae were also identified molecularly as Amphimerus sp. in four fish species, i.e., Rhoadsia altipinna, Bryconamericus bucay, Andinoacara rivulatus, and Piabucina aureoguttata. Metacercariae of the heterophyid Haplorchis pumilio were also found in the four fish species examined. This is the first study to confirm the current endemicity of Amphimerus sp. in Pedro Pablo Gómez, Manabí, Ecuador. The adult worms isolated here shared morphological characteristics with previous Amphimerus sp. descriptions and were molecularly similar to Amphimerus sp. described in the province of Esmeraldas. Moreover, this study is the first to document four fish species as infection sources of Amphimerus sp. detected via a molecular protocol targeting the metacercariae of the parasite. Fish species identified here should be targeted for public health campaigns to avoid further human liver-fluke infections by Amphimerus sp. or potential intestinal-fluke infections by H. pumilio or others.


Assuntos
Doenças dos Peixes/epidemiologia , Hepatopatias Parasitárias/veterinária , Opisthorchidae/isolamento & purificação , Infecções por Trematódeos/veterinária , Zoonoses/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Gatos , Criança , Pré-Escolar , Estudos Transversais , Cães , Equador/epidemiologia , Fezes/parasitologia , Feminino , Peixes , Humanos , Lactente , Hepatopatias Parasitárias/epidemiologia , Masculino , Pessoa de Meia-Idade , Infecções por Trematódeos/epidemiologia , Adulto Jovem , Zoonoses/parasitologia
4.
Parasitol Int ; 72: 101939, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31201922

RESUMO

Adult Cryptocotyle lata sp. nov. worms were obtained from experimental studies. In the Russian southern Far East, the life cycle of this parasite is carried out using freshwater snails (Boreoelona ussuriensis), freshwater fish, and birds as the first intermediate, second intermediate, and definitive hosts, respectively. The morphological indices of C. lata sp. nov. are closest to Cryptocotyle concava; however, these two species differ in terms of their sizes of body, oral and ventral suckers, eggs, and the shape of their testes and ovaries. Analysis of the life cycles of the Cryptocotyle representatives suggested that C. concava were at least two cryptic species, one of which circulates using brackish water Hydrobia snails, and the other using freshwater Amnicola snails as the first intermediate hosts. Molecular data (i.e., the 28S gene and the second internal transcribed spacer (ITS2) of rDNA) were used to analyze the phylogenetic relationships of C. lata sp. nov. and other representatives of Opisthorchioidea. The long repeats and secondary structure of the ITS1 region were studied. Representatives of the Opisthorchiidae and several species from Heterophyidae (including the genus Cryptocotyle) were found to have molecular features that suggested that these species belonged to Opisthorchiidae. At the same time, the genetic relatedness of worms, which are united in common clusters on phylogenetic trees, is consistent with the use of the first intermediate hosts from different taxonomic groups in their life cycles; namely, snails of the Truncatelloidea are hosts of trematodes from a cluster with Opisthorchiidae and a number species of the family Heterophyidae, while snails of the Cerithioidea are hosts of worms from a cluster that includes only the Heterophyidae. In addition, the results of genetic studies indicate that Clonorchis sinensis, Metorchis ussuriensis, Metorchis bilis, Metorchis xanthosomus, and Metorchis orientalis should be included in the genus Opisthorchis.


Assuntos
Opisthorchidae/classificação , Filogenia , Caramujos/parasitologia , Animais , DNA de Helmintos/genética , DNA Espaçador Ribossômico/genética , Peixes/parasitologia , Estágios do Ciclo de Vida , Opisthorchidae/anatomia & histologia , Opisthorchidae/isolamento & purificação , RNA Ribossômico 28S/genética , Federação Russa
5.
PLoS One ; 13(10): e0203811, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30286114

RESUMO

BACKGROUND: Recently, a high prevalence of infection by the liver fluke Amphimerus spp. has been documented in the Chachi Amerindians of Ecuador. For diagnosis, no studies exist that compare the sensitivity of different coproparasitological detection techniques. The present study compares the Kato-Katz technique with three other coproparasitological methods for detecting eggs of Amphimerus in stools, as well as determines the prevalence of infection in Chachi residents in a Tropical rain forest area in the northwest coast of Ecuador. METHODOLOGY/RESULTS: A total of 105 samples, utilizing the Kato-Katz technique (KK), the spontaneous sedimentation technique in tube (SSTT), the formalin-ether concentration technique (FEC), and direct smear microscopy (DM), were examined. Combining the four methods (fixed "gold" standard), 38 samples were positive with a prevalence of infection of 36.2%. The sensitivities of individual methods were 71%, 58%, 50% and 3% for KK, SSTT, FEC, and DM respectively. Our results indicated that KK alone had the best performance, detecting 27 (71%) of the 38 positive samples. The combination of KK and SSTT detected amphimeriasis in 36 (95%) samples, and KK and FEC in 31 (82%) samples. CONCLUSIONS: DM showed the lowest sensitivity, which raises concern for its value, because it is the standard technique for stool examination for detection of parasites in both public and private laboratories in Ecuador. SSTT alone detected eggs in 22 samples (58%) and would be recommended for field studies because of its simplicity. Performing two techniques on a single sample enhances the detection of Amphimerus infection. Its sensitivity is relative to a fixed "gold" standard, determined as the combined results of the four techniques performed. This study confirms the high prevalence of human infection by Amphimerus in the indigenous Chachi group where the first human cases were described.


Assuntos
Opisthorchidae/isolamento & purificação , Contagem de Ovos de Parasitas/métodos , Infecções por Trematódeos/diagnóstico , Infecções por Trematódeos/epidemiologia , Adolescente , Adulto , Animais , Criança , Pré-Escolar , Estudos Transversais , Equador/etnologia , Fezes/parasitologia , Feminino , Humanos , Lactente , Masculino , Sensibilidade e Especificidade , Adulto Jovem
6.
Acta Vet Scand ; 59(1): 75, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29089028

RESUMO

The intention to increase roach (Rutilus rutilus) consumption is in focus for ecological and economic reasons in Finland. However, its safety as food has not been considered comprehensively. We collected and artificially digested 85 roach halves originating from the south-eastern coast of Finland, and found trematode metacercariae in 98.8% of the samples. Based on polymerase chain reaction (PCR) and sequencing of amplicons generated from the ITS2 gene region, zoonotic parasites of the family Opistorchiidae were identified as Pseudamphistomum truncatum and Metorchis bilis, and also non-zoonotic Holostephanus dubinini (family Cyathocotylidae) and Posthodiplostomum spp. (family Diplostomidae) were identified. The species identity of other trematodes found is currently being investigated. Mixed infections of several trematode species were common. The prevalence of morphologically identified zoonotic P. truncatum was 46%, and zoonotic M. bilis was found in one sequence sample. The high prevalence of zoonotic trematode metacercariae in roach from the Gulf of Finland is alarming. Only thoroughly cooked roach products can be recommended for human or animal consumption from the area.


Assuntos
Cyprinidae/parasitologia , Doenças dos Peixes/epidemiologia , Trematódeos/fisiologia , Infecções por Trematódeos/veterinária , Animais , Coinfecção/epidemiologia , Coinfecção/parasitologia , Coinfecção/veterinária , DNA Espaçador Ribossômico/genética , Finlândia/epidemiologia , Doenças dos Peixes/parasitologia , Oceanos e Mares , Opisthorchidae/classificação , Opisthorchidae/genética , Opisthorchidae/isolamento & purificação , Opisthorchidae/fisiologia , Prevalência , Trematódeos/classificação , Trematódeos/genética , Trematódeos/isolamento & purificação , Infecções por Trematódeos/epidemiologia , Infecções por Trematódeos/parasitologia
7.
PLoS Negl Trop Dis ; 11(6): e0005672, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28628614

RESUMO

BACKGROUND: Amphimeriasis is a fish-borne disease caused by the liver fluke Amphimerus spp. that has recently been reported as endemic in the tropical Pacific side of Ecuador with a high prevalence in humans and domestic animals. The diagnosis is based on the stool examination to identify parasite eggs, but it lacks sensitivity. Additionally, the morphology of the eggs may be confounded with other liver and intestinal flukes. No immunological or molecular methods have been developed to date. New diagnostic techniques for specific and sensitive detection of Amphimerus spp. DNA in clinical samples are needed. METHODOLOGY/PRINCIPAL FINDINGS: A LAMP targeting a sequence of the Amphimerus sp. internal transcribed spacer 2 region was designed. Amphimerus sp. DNA was obtained from adult worms recovered from animals and used to optimize the molecular assays. Conventional PCR was performed using outer primers F3-B3 to verify the proper amplification of the Amphimerus sp. DNA target sequence. LAMP was optimized using different reaction mixtures and temperatures, and it was finally set up as LAMPhimerus. The specificity and sensitivity of both PCR and LAMP were evaluated. The detection limit was 1 pg of genomic DNA. Field testing was done using 44 human stool samples collected from localities where fluke is endemic. Twenty-five samples were microscopy positive for Amphimerus sp. eggs detection. In molecular testing, PCR F3-B3 was ineffective when DNA from fecal samples was used. When testing all human stool samples included in our study, the diagnostic parameters for the sensitivity and specificity were calculated for our LAMPhimerus assay, which were 76.67% and 80.77%, respectively. CONCLUSIONS/SIGNIFICANCE: We have developed and evaluated, for the first time, a specific and sensitive LAMP assay for detecting Amphimerus sp. in human stool samples. The procedure has been named LAMPhimerus method and has the potential to be adapted for field diagnosis and disease surveillance in amphimeriasis-endemic areas. Future large-scale studies will assess the applicability of this novel LAMP assay.


Assuntos
Fezes/parasitologia , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Opisthorchidae/isolamento & purificação , Infecções por Trematódeos/diagnóstico , Animais , DNA de Helmintos/genética , DNA Espaçador Ribossômico/genética , Equador , Humanos , Opisthorchidae/genética , Sensibilidade e Especificidade , Infecções por Trematódeos/parasitologia
8.
Parasitol Int ; 65(3): 258-67, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26794684

RESUMO

Metorchis spp. are flukes (Platyhelminthes: Digenea) that infect vertebrates, including humans, dogs, cats, poultry and wild game, with cyprinid freshwater fish serving as typical second intermediate hosts. In their definitive hosts, the Metorchis spp. are difficult to identify to species. We provide and analyze sequences of two nuclear (18S rDNA and ITS2) and two mitochondrial (CO1 and ND1) DNA loci of four morphologically identified European species of the Metorchis, namely Metorchis albidus, Metorchis bilis, Metorchis crassiusculus and Metorchis xanthosomus, and of another opisthorchiid, Euamphimerus pancreaticus. DNA analysis suggests that the Metorchis specimens identified morphologically as M. albidus (from Lutra lutra), M. bilis (from Phalacrocorax carbo) and M. crassiusculus (from Aquila heliaca and Buteo rufinus) represent a single species. Thus, M. albidus (Braun, 1893) Loos, 1899 and M. crassiusculus (Rudolphi, 1809) Looss, 1899 are recognized as junior subjective synonyms of M. bilis (Braun, 1790) Odening, 1962. We also provide comparative measurements of the Central European Metorchis spp., and address their tissue specificity and prevalence based on the examination of extensive bird cohort from 1962 to 2015. M. bilis and M. xanthosomus can be morphologically diagnosed by measuring the extent of genitalia relative to body length and by the size ratio of their suckers. They also differ in their core definitive hosts, with ducks (Anas, Aythya) and coots (Fulica) hosting M. xanthosomus, and cormorants (Phalacrocorax), the birds of prey (Buteo, Aquila, etc.), piscivorous mammals (Lutra, Vulpes, Ursus, etc.) and humans hosting M. bilis. Previous reports on the Metorchis spp. contain numerous suspected misidentifications.


Assuntos
Opisthorchidae/classificação , Infecções por Trematódeos/parasitologia , Animais , Aves , DNA Ribossômico/genética , Humanos , Mamíferos , Opisthorchidae/citologia , Opisthorchidae/genética , Opisthorchidae/isolamento & purificação , Filogenia , RNA Ribossômico 18S/genética , Análise de Sequência de DNA , Especificidade da Espécie
9.
PLoS Negl Trop Dis ; 9(2): e0003526, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25647171

RESUMO

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.


Assuntos
Doenças do Gato/epidemiologia , Doenças do Cão/epidemiologia , Hepatopatias Parasitárias/veterinária , Opisthorchidae/isolamento & purificação , Infecções por Trematódeos/veterinária , Zoonoses/epidemiologia , Animais , Gatos , Cães , Equador/epidemiologia , Feminino , Humanos , Hepatopatias Parasitárias/epidemiologia , Dados de Sequência Molecular , Prevalência , Infecções por Trematódeos/epidemiologia
10.
Eksp Klin Gastroenterol ; (4): 54-9, 2012.
Artigo em Russo | MEDLINE | ID: mdl-23402155

RESUMO

THE PURPOSE OF THE REVIEW: Present new data on the causative agent, pathogenesis, diagnosis and treatment of opisthorchiasis. RECENT LITERATURE DATA: When samples of parasites were genotyped by novel nuclear marker Pm-int9, it was shown various properties of Opisthorchis viverrini, O. felineus and C. sinensis. It has been proven the oxidant damage to DNA of biliary epithelium cells infected with opisthorchiasis, and overexpressed of cellular protooncogene c-Ski, as well as platelet-derived growth factor alpha (Pdgfa) gene, which in some cases leads to the development of cholangiocarcinoma. Describes the innovations in the diagnosis of opisthorchiasis: primers OP1 and OP2 are used to amplify the ITS2 region rDNK eggs and metacercariae of Opisthorchis in feces. Opisthorchiasis treatment remains traditional - praziquantel, at least - with albendazole. Treatment of opisthorchiasis patients with praziquantel was shown to reduce inflammation-mediated tissue damage and carcinogenesis.


Assuntos
Opistorquíase , Opisthorchidae/efeitos dos fármacos , Animais , Anti-Helmínticos/administração & dosagem , Anti-Helmínticos/efeitos adversos , Anti-Helmínticos/uso terapêutico , Terapia Combinada , DNA de Helmintos/genética , Quimioterapia Combinada , Fezes/parasitologia , Humanos , Opistorquíase/epidemiologia , Opistorquíase/parasitologia , Opistorquíase/terapia , Opisthorchidae/isolamento & purificação , Modalidades de Fisioterapia , Praziquantel/administração & dosagem , Praziquantel/efeitos adversos , Praziquantel/uso terapêutico
11.
Emerg Infect Dis ; 17(12): 2331-4, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22172165

RESUMO

Amphimerus spp. flukes are known to infect mammals, but human infections have not been confirmed. Microscopy of fecal samples from 397 persons from Ecuador revealed Opisthorchiidae eggs in 71 (24%) persons. Light microscopy of adult worms and scanning electron microscopy of eggs were compatible with descriptions of Amphimerus spp. This pathogen was only observed in communities that consumed undercooked fish.


Assuntos
Hepatopatias Parasitárias/epidemiologia , Opisthorchidae , Infecções por Trematódeos/epidemiologia , Adolescente , Adulto , Idoso , Animais , Criança , Pré-Escolar , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/parasitologia , Equador/epidemiologia , Feminino , Peixes/parasitologia , Parasitologia de Alimentos , Humanos , Hepatopatias Parasitárias/parasitologia , Masculino , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Opisthorchidae/isolamento & purificação , Opisthorchidae/ultraestrutura , Prevalência , Infecções por Trematódeos/parasitologia , Adulto Jovem
12.
Acta Trop ; 103(1): 26-32, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17574199

RESUMO

This study aimed to discriminate infections of two common fish-borne trematodes in Thailand, Opisthorchis viverrini from Haplorchis taichui, based on mitochondrial cytochrome c oxidase subunit I (COI) gene. Designed primers (COI-OV-Hap F&R primers) amplified partial COI fragments of O. viverrini and H. taichui with high sensitivity in different developmental stages (adult, metacercaria, and egg). Polymerase chain reaction (PCR) amplicons were generated with low genomic DNA concentration ( approximately 10(-4)ng) of O. viverrini and H. taichui at 50 and 56 degrees C annealing temperatures, respectively. At 50 degrees C, COI fragments of Clonorchis sinensis and H. taichui were also obtained, but this was less sensitive than O. viverrini. At 56 degrees C, only H. taichui could be amplified and discriminated from H. pumilio, H. yogokawai, O. viverrini, and C. sinensis. Between 50 and 56 degrees C, the PCR amplicons of H. pumilio and H. yogokawai were amplified with low specificity and low sensitivity. The genetic characters among O. viverrini, C. sinensis, and H. taichui were distinguished by PCR-RFLP method. The PCR-RFLP profiles might be useful for diagnosing mixed O. viverrini and H. taichui infections in endemic areas, and for detecting metacercariae of O. viverrini, C. sinensis and H. taichui in epidemiological surveys of infections in fish hosts.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/genética , Opisthorchidae/classificação , Opisthorchidae/genética , Animais , Sequência de Bases , Marcadores Genéticos/genética , Opisthorchidae/isolamento & purificação , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Sensibilidade e Especificidade , Especificidade da Espécie
13.
Parasitol Res ; 100(4): 905-9, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17061114

RESUMO

Infections with the opisthorchiid liver flukes Clonorchis sinensis, Opisthorchis viverrini, and Opisthorchis felineus cause serious health problems in endemic areas of Southeast Asia and countries of the former Soviet Union. Chronic infections--even with low worm burdens--may lead to the development of fatal cholangiocarcinoma and related symptoms. A more sensitive diagnosis is needed since the tiny eggs of the worms are often not seen in microscopic examinations of stool samples, especially in patients with low infections. This communication reports a rapid cleanup procedure for human stool samples, which enables reliable identification of DNA by polymerase chain reaction from few eggs of opisthorchiid flukes in fecal samples.


Assuntos
Primers do DNA/genética , Fezes/parasitologia , Opisthorchidae/genética , Opisthorchidae/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Infecções por Trematódeos/diagnóstico , Animais , Sequência de Bases , Gatos , Humanos , Dados de Sequência Molecular , Opisthorchidae/classificação , Roedores/parasitologia , Sensibilidade e Especificidade , Especificidade da Espécie , Fatores de Tempo
14.
Artigo em Chinês | MEDLINE | ID: mdl-16866154

RESUMO

Parafossarulus striatulus, Pseudorasbora parva and brood ducks are involved in the lifecycle of Metorchis orientalis. Natural nidi of M. orientalis are confirmed in Huaihe River Basin.


Assuntos
Opisthorchidae/crescimento & desenvolvimento , Rios/parasitologia , Animais , China , Monitoramento Ambiental , Opisthorchidae/isolamento & purificação
15.
Med Parazitol (Mosk) ; (4): 3-8, 2006.
Artigo em Russo | MEDLINE | ID: mdl-17290900

RESUMO

In the context of the present-day teaching of parasitocenoses and the proposition that the pathogen's population is the only compulsory and specific component of a natural focus, the author brings to light the ecological bases of the combination of natural foci of metorchiases, bilharziasis, opisthorchiasis, and methorchiasis (M. xanthosomus). Two first foci are one-host population-combined and the latter focus is a two-host population-combined focus. While analyzing the combination of foci, it is expedient to consider in pairs since this provides a way of identifying the bases of the combination, which are unique to these foci, and determining the level, pattern, type, and degree of the combination of foci and, on their basis, the type of a combined focus. It is noted that in biohelminthiases, detection of even hemipopulations of parasites points to the presence of natural foci. The morphological structure of the floodplain-river landscape of the Konda River acts as the abiotic basis of the combination of foci. The parasitic systems of flukes, the parasitocenoses of co-acting hemipopulations of the pathogens and populations of hosts, the structure of foci, the species-specific composition of ecosystems, and the ecological relations of Trematoda hosts act as the biotic bases of the combination of foci of Trematoda infections. The host susceptibility to infection with Trematoda hemipopulations and the multihostality of B. polonica and M. xanthosomus act as the epizootic bases of the combination of foci. The abiotic, biotic, and epizootic bases of the combination are, in the aggregate, the ecological bases of the combination of natural foci of zoonoses.


Assuntos
Arvicolinae/parasitologia , Doenças das Aves/parasitologia , Reservatórios de Doenças/parasitologia , Ecossistema , Doenças dos Peixes/parasitologia , Peixes/parasitologia , Água Doce , Helmintíase Animal/parasitologia , Moluscos/parasitologia , Infecções por Trematódeos/veterinária , Zoonoses/parasitologia , Animais , Aves/parasitologia , Opisthorchidae/classificação , Opisthorchidae/isolamento & purificação , Densidade Demográfica , Sibéria , Especificidade da Espécie , Infecções por Trematódeos/parasitologia
16.
Med Parazitol (Mosk) ; (4): 34-7, 2006.
Artigo em Russo | MEDLINE | ID: mdl-17290907

RESUMO

The paper presents the results of a study of the infection rates of mollusks of the family Bythiniidae (Bithynia tentaculata, Opisthorchophorus troscheli) and fishes with the larval stages of Opisthorchidae in different districts of the Yaroslavl Region. A total of 3,708 mollusks from the water reservoirs of different types (small rivers, lakes, ponds, and canals) were examined in the Nekouzsky, Yaroslavsky, and Pereslavsky Districts of the Yaroslavl Region in 1989 to 1999. Opisthorchis cercarias were found in 7 of the 10 studied water reservoirs. The total rate of infection of mollusks with all types with Trematoda partenitas and cercarias in different water reservoirs averaged 18.5 +/- 3.5% for Bithynia tentaculata and 19.1 +/- 4.1% for Opisthorchophorus troscheli. Trematoda metacercarias of the family Opisthorchidae were revealed in roaches, ides, verkhovkas, silver breams, and chubs in four different water reservoirs (small rivers and a lake) of the region. Pseudamphistomum truncates, Opisthorchis felineus, and Metorchis xanthosomus were present among the metacercarias found. It is concluded that there may be sporadic cases of Opisthorchis infection in wild and domestic animals and humans in the Yaroslavl Region.


Assuntos
Ecossistema , Doenças dos Peixes/prevenção & controle , Peixes/parasitologia , Moluscos/parasitologia , Opisthorchidae/isolamento & purificação , Infecções por Trematódeos/veterinária , Animais , Peixes/classificação , Água Doce , Larva , Opisthorchidae/fisiologia , Federação Russa/epidemiologia , Especificidade da Espécie , Infecções por Trematódeos/prevenção & controle
17.
Artigo em Inglês | MEDLINE | ID: mdl-16438194

RESUMO

Killing factors, various temperatures and solutions were studied in the laboratory on Stellantchasmus falcatus metacercaria in half-beaked fish (Dermogenus pusillus). Killing criteria followed the Movability Index from 1.000 within 24 hours. The metacercariae were collected from Chiang Mai moat. They were incubated in 0.85 % NaCl at -20 degrees C, room temperature, 4 degrees, 37 degrees, and 65 degrees C. The in vitro investigation showed that at -20 degrees C and 65 degrees C, the worms were killed within 18 and 2 hours, respectively, while other temperatures produced no effect. The solutions investigated were NaCl (10, 20, 30, and 40%), lemon juice (25, 50, 75, and 100%), acetic acid (5, 10, 20, and 30%), vinegar (1, 3, and 5%) and water as a control. The worms were killed in NaCl at 20, 30, and 40% within 12, 6, and 2 hours, respectively. Acetic acid at 5% and 10% killed the metacercaria within 12 and 6 hours while at 20% and 30%, within 2 hours. The killing effect of 3% vinegar was found within 18 hours and of 5% vinegar within 12 hours. Lemon juice showed no killing effect.


Assuntos
Peixes/parasitologia , Contaminação de Alimentos , Manipulação de Alimentos/métodos , Opisthorchidae/efeitos dos fármacos , Alimentos Marinhos/parasitologia , Infecções por Trematódeos/diagnóstico , Ácido Acético/farmacologia , Animais , Humanos , Técnicas In Vitro , Opisthorchidae/isolamento & purificação , Cloreto de Sódio/farmacologia , Sobrevida
18.
Artigo em Inglês | MEDLINE | ID: mdl-12971550

RESUMO

Half-beaked fish, Dermogenus pusillus, collected from Mueang, Hang Dong, Doi Saket and Saraphi Districts, Chiang Mai Province, were examined for their infection status with Stellantchasmus falcatus (Digenea: Heterophyidae) metacercariae. The infection rate of the fish was 100%. Fish in three of four districts were found only to have metacercariae of S. falcatus, whereas those in Saraphi District had mixed infections with metacercariae of Posthodiplostomum sp. The intensity of S. falcatus infection per fish varied; 652-1,342 (mean 999.5), 562-2,422 (1,323.1), 185-2,492 (502.6), and 22-550 (210.4) in Mueang, Hang Dong, Saraphi, and Doi Saket Districts, respectively. The body portions of the fish with the heaviest metacercarial infection were the muscles, in all districts. The present study confirms that half-beaked fish in Chiang Mai Province are heavily infected with S. falcatus metacercariae.


Assuntos
Peixes/parasitologia , Opisthorchidae/isolamento & purificação , Infecções por Trematódeos/parasitologia , Animais , Água Doce/parasitologia , Humanos , Alimentos Marinhos/parasitologia , Água do Mar/parasitologia , Tailândia , Infecções por Trematódeos/epidemiologia
19.
Parasitol Res ; 90(5): 409-14, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12748848

RESUMO

Adult specimens of the opisthorchiid liver fluke species Opisthorchis felineus and Metorchis bilis could be identified for the first time by molecular biological methods using species specific primers (OF and MB primers) in the polymerase chain reaction (PCR). The OF or MB primers were based on a part of the mitochondrial cytochrome c oxidase I gene. A specific product of approximately 200 bp could be amplified for O. felineus by means of the specific O. felineus primers. By contrast, the amplification of M. bilis DNA with MB primers produced a fragment of approximately 110 bp. A specificity of 100% could be demonstrated for both primer pairs. The sensitivities of the PCRs were 10 pg for the O. felineus DNA and 100 fg for the M. bilis DNA.


Assuntos
Opisthorchidae/classificação , Opisthorchis/classificação , Reação em Cadeia da Polimerase , Animais , Primers do DNA , DNA de Helmintos/análise , DNA de Helmintos/genética , DNA Mitocondrial/análise , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Opistorquíase/parasitologia , Opistorquíase/veterinária , Opisthorchidae/genética , Opisthorchidae/isolamento & purificação , Opisthorchis/genética , Opisthorchis/isolamento & purificação , Sensibilidade e Especificidade , Infecções por Trematódeos/parasitologia , Infecções por Trematódeos/veterinária
20.
Berl Munch Tierarztl Wochenschr ; 114(5-6): 193-6, 2001.
Artigo em Alemão | MEDLINE | ID: mdl-11413713

RESUMO

396 red foxes originating from the city of Berlin were examined for opisthorchiid liver flukes and clinical sarcoptic mange between January 1997 and March 1998. Out of 232 (= 58.6%) foxes positive for opisthorchiid flukes 221 animals harboured Metorchis bilis and 70 were infected with Opisthorchis felineus. Pseudamphistomum truncatum was found only in 8 foxes. M. bilis occurred as mono-infection in 154 animals. M. bilis in combination with O. felineus was found in 61 cases. Pure Opisthorchis infection as well as other fluke combinations were found in a small number of animals only. 85 (= 21.5%) foxes showed clinical sarcoptic mange. Liver fluke positive foxes showed a higher mange prevalence than uninfected animals. However, significant associations between flukes and manage were only found when comparing uninfected foxes with those having the highest worm burden. The association of liver flukes and mange could be established for adult female foxes by a significant Odds Ratio of 4.3.


Assuntos
Raposas/parasitologia , Opisthorchidae/isolamento & purificação , Escabiose/veterinária , Infecções por Trematódeos/veterinária , Animais , Berlim/epidemiologia , Feminino , Masculino , Razão de Chances , Prevalência , Escabiose/complicações , Escabiose/epidemiologia , Infecções por Trematódeos/complicações , Infecções por Trematódeos/epidemiologia
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