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1.
J Parasitol ; 107(5): 739-761, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34546335

RESUMO

The role of invertebrates in some acanthocephalan life cycles is unclear because juvenile acanthocephalans are difficult to identify to species using morphology. Most reports suggest acanthocephalans from turtle definitive hosts use ostracods as intermediate hosts and snails as paratenic hosts. However, laboratory studies of the life cycle suggest that ostracods and snails are both required hosts in the life cycle. To elucidate the role of ostracods and snails in acanthocephalan life cycles better, we collected 558 freshwater snails of 2 species, including Planorbella cf. Planorbella trivolvis and Physa acuta, from 23 wetlands in Oklahoma, U.S.A., and examined them for acanthocephalan infections. Additionally, we examined 37,208 ostracods of 4 species, Physocypria sp. (morphotype 1), Cypridopsis sp., Stenocypris sp., and Physocypria sp. (morphotype 2) for juvenile acanthocephalans from 2 wetlands in Oklahoma. Juvenile acanthocephalans were morphologically characterized, and the complete internal transcribed spacer (ITS) region of nuclear rDNA was sequenced from acanthocephalans infecting 11 ostracod and 13 snail hosts. We also sampled 10 red-eared slider turtles, Trachemys scripta elegans, and 1 common map turtle, Graptemys geographica, collected from Oklahoma, Arkansas, and Texas and recovered 1,854 adult acanthocephalans of 4 species. The ITS of 17 adult acanthocephalans of 4 species from turtle hosts were sequenced and compared to juvenile acanthocephalan sequences from ostracod and snail hosts from this study and GenBank to determine conspecificity. Of the 23 locations sampled for snails, 7 (30%) were positive for juvenile acanthocephalans in the genus Neoechinorhynchus. The overall prevalence and mean intensity of acanthocephalans in Planorbella cf. P. trivolvis and P. acuta were 20% and 2 (1-6) and 2% and 1 (1), respectively. In contrast, only 1 of 4 species of ostracods, Physocypria sp. (morphotype 1), was infected with larval/juvenile Neoechinorhynchus spp. with an overall prevalence of 0.1% and a mean intensity of 1 (1-2). Although 4 species of acanthocephalans infected turtle definitive hosts, including Neoechinorhynchus chrysemydis, Neoechinorhynchus emydis, Neoechinorhynchus emyditoides, and Neoechinorhynchus pseudemydis, all the ITS sequences from cystacanths infecting snail hosts were conspecific with N. emydis. In contrast, the ITS sequences from larval/juvenile acanthocephalans from ostracods were conspecific with 2 species of acanthocephalans from turtles (N. emydis and N. pseudemydis) and 1 species of acanthocephalan from fish (Neoechinorhynchus cylindratus). These results indicate that N. emydis infects freshwater snails, whereas other species of Neoechinorhynchus appear not to infect snail hosts. We document new ostracod and snail hosts for Neoechinorhynchus species, including the first report of an ostracod host for N. pseudemydis, and we provide novel molecular barcodes that can be used to determine larva, juvenile, and adult conspecificity of Neoechinorhynchus species.


Assuntos
Acantocéfalos/genética , Crustáceos/parasitologia , Caramujos/parasitologia , Tartarugas/parasitologia , Acantocéfalos/anatomia & histologia , Acantocéfalos/isolamento & purificação , Acantocéfalos/patogenicidade , Animais , DNA de Helmintos/química , DNA de Helmintos/isolamento & purificação , Feminino , Água Doce , Masculino , Estações do Ano , Análise Espacial
2.
Parasitology ; 148(8): 913-933, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33775267

RESUMO

The predator­prey-transmitted cestode Taenia hydatigena infects a wide range of definitive and intermediate hosts all over the world. Domestic and sylvatic cycles of transmission are considered as well. The parasite has considerable economic importance, particularly in sheep. Here, the molecular characters of T. hydatigena cysticerci in sheep from the Nile Delta, Egypt were investigated for the first time. For this purpose, 200 sheep carcasses and their offal were inspected at the municipal abattoir, Dakahlia governorate, Egypt. Cysticerci of T. hydatigena were collected and molecularly characterized employing the mitochondrial 12S rRNA gene. Cysticerci were found in 42 (21%) sheep, mostly attached to the omenti, mesenteries and livers. After molecular confirmation, nine isolates were sequenced displaying six different haplotypes. Analysis of the T. hydatigena 12S rRNA nucleotide sequences deposited in GenBank revealed 55 haplotypes out of 69 isolates, displaying high haplotype (0.797) and low nucleotide (0.00739) diversities. For the Tajima D neutrality index, a negative value (−2.702) was determined, indicating the population expansion of the parasite. Additionally, global data summarized in this study should be useful to set up effective control strategies against this ubiquitous parasite.


Assuntos
Cysticercus/genética , Doenças dos Ovinos/parasitologia , Teníase/parasitologia , Animais , Análise por Conglomerados , Cysticercus/classificação , DNA de Helmintos/química , DNA de Helmintos/isolamento & purificação , Egito/epidemiologia , Feminino , Saúde Global , Haplótipos , Masculino , Filogenia , Polimorfismo Genético , RNA Ribossômico/genética , Rios , Alinhamento de Sequência , Ovinos , Doenças dos Ovinos/epidemiologia , Taenia/classificação , Taenia/genética , Teníase/epidemiologia
3.
Parasitology ; 148(3): 311-326, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33092662

RESUMO

Cysticercosis caused by the metacestode larval stage of Taenia hydatigena formerly referred to as Cysticercus tenuicollis is a disease of veterinary importance that constitutes a significant threat to livestock production worldwide, especially in endemic regions due to condemnation of visceral organs and mortality rate of infected young animals. While the genetic diversity among parasites is found to be potentially useful in many areas of research including molecular diagnostics, epidemiology and control, that of T. hydatigena across the globe remains poorly understood. In this study, analysis of the mitochondrial DNA (mtDNA) of adult worms and larval stages of T. hydatigena isolated from dogs, sheep and a wild boar in China showed that the population structure consists of two major haplogroups with very high nucleotide substitutions involving synonymous and non-synonymous changes. Compared with other cestodes such as Echinococcus spp., the genetic variation observed between the haplogroups is sufficient for the assignment of major haplotype or genotype division as both groups showed a total of 166 point-mutation differences between the 12 mitochondrial protein-coding gene sequences. Preliminary analysis of a nuclear protein-coding gene (pepck) did not reveal any peculiar changes between both groups which suggests that these variants may only differ in their mitochondrial makeup.


Assuntos
DNA de Helmintos/genética , DNA Mitocondrial/genética , Taenia/genética , Teníase/veterinária , Sequência de Aminoácidos , Animais , China , DNA de Helmintos/química , DNA de Helmintos/metabolismo , DNA Mitocondrial/química , DNA Mitocondrial/metabolismo , Doenças do Cão/parasitologia , Cães , Haplótipos , Larva/genética , Larva/crescimento & desenvolvimento , Filogenia , Alinhamento de Sequência , Ovinos , Doenças dos Ovinos/parasitologia , Carneiro Doméstico , Sus scrofa , Suínos , Doenças dos Suínos/parasitologia , Taenia/crescimento & desenvolvimento , Taenia/metabolismo , Teníase/parasitologia
4.
PLoS Negl Trop Dis ; 14(3): e0008147, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32155159

RESUMO

BACKGROUND: Echinococcosis is a chronic zoonosis caused by tapeworms of the genus Echinococcus. Treatment of the disease is often expensive and complicated, sometimes requiring extensive surgery. Ultrasonographic imaging is currently the main technique for diagnosis, while immunological analysis provides additional information. Confirmation still needs pathological analysis. However, these diagnostic techniques generally detect infection in late stages of the disease. An accurate, early and non-invasive molecular diagnostic method is still unavailable. METHODOLOGY/PRINCIPAL FINDINGS: We sequenced the cell-free DNA (cfDNA) from plasma of echinococcosis patients and confirmed the presence of Echinococcus DNA. To improve detection sensitivity, we developed a method based on targeted next-generation sequencing of repeat regions. Simulation experiments demonstrate that the targeted sequencing is sensitive enough to detect as little as 0.1% of an Echinococcus genome in 1 mL of plasma. Results obtained using patient plasma shows that the Area Under the Curve (AUC) of the method is 0.862, with a detection sensitivity of 62.50% and specificity of 100%, corresponding to a Youden-index of 0.625. CONCLUSIONS/SIGNIFICANCE: This study provides evidence that hydatid cysts release cfDNA fragments into patient plasma. Using the repeat region targeted sequencing method, highly specific detection of Echinococcus infection was achieved. This study paves a new avenue for potential non-invasive screening and diagnosis of echinococcosis.


Assuntos
DNA de Helmintos/sangue , Equinococose/diagnóstico , Echinococcus/genética , Técnicas de Diagnóstico Molecular/métodos , Plasma/química , Sequências Repetitivas de Ácido Nucleico , Adulto , Animais , DNA de Helmintos/química , DNA de Helmintos/genética , DNA de Helmintos/isolamento & purificação , Feminino , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Masculino , Sensibilidade e Especificidade
5.
Mem. Inst. Oswaldo Cruz ; 115: e200115, 2020.
Artigo em Inglês | LILACS, Sec. Est. Saúde SP | ID: biblio-1135228

RESUMO

In January and February 2019, a malacological survey was conducted in the area surrounding the residence of a 12-year-old child that had contracted cerebral angiostrongyliasis in the municipality of Macapá, capital of the Amapá State, northern Brazil. The serological examination was positive for Angiostrongylus cantonensis infection, the principal etiological agent of this parasitosis. A sample of 54 molluscs was artificially and individually digested for parasitological analysis, containing 38 specimens of Achatina fulica, nine specimens of Bulimulus tenuissimus and seven specimens of Sarasinula linguaeformis. A. fulica was the most abundant mollusc, and the only species infected with A. cantonensis, as well as presenting co-infections with other nematodes. This is the first report of cerebral angiostrongyliasis in the Amazon Region, and the first record of A. fulica infected with A. cantonensis in Amapá. These findings highlight the potential risks of human angiostrongyliasis, and the need to implement public health measures to control the spread of the disease.


Assuntos
Humanos , Animais , Criança , Caramujos/parasitologia , Infecções por Strongylida/diagnóstico , Infecções por Strongylida/veterinária , Angiostrongylus cantonensis/isolamento & purificação , Brasil , Anticorpos Anti-Helmínticos , Cidades , Infecções por Strongylida/parasitologia , DNA de Helmintos/genética , DNA de Helmintos/química
6.
Turkiye Parazitol Derg ; 43(4): 175-181, 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31865652

RESUMO

Objective: Hydatidosis is a zoonotic parasitic infection caused by the larval stage of Echinococcus granulosus. The aim of this study was to investigate the biochemical structures of germinal membrane and cyst fluids obtained from patients with liver involvement during surgery, by Raman spectroscopy at the molecular level. Methods: Molecular characterization of germinal membrane and cyst fluid according to mitochondrial gene region was determined and phylogenetic analysis was performed. Raman spectroscopy was used in samples and spectral bands between 300 and 1800 cm-1 were examined. Results: As a result of PCR, approximately 400 bp DNA band was obtained from germinal membranes and cyst fluids gathered from patients. Peaks were observed at 780, 880, 970, 1151, 1200, 1270 cm-1 for germinal membrane and at 780 and 1200 cm-1 for cyst fluid. The highest spectral bands were obtained at 1333-1335 cm-1 and were determined to be modes indicating the CH3CH2 collagen and polynucleotide chain. Conclusion: In the identification of microorganisms and biochemical analysis of biological tissues; different diagnostic methods such as molecular, serological and conventional methods are used. In addition to these methods, Raman spectroscopy has been shown in studies to be a fast, non-destructive and noninvasive method. Therefore, it is thought to be an alternative method for analyzing the basic biochemical components of microorganisms at molecular level.


Assuntos
Equinococose Hepática/diagnóstico por imagem , Echinococcus granulosus/classificação , Zoonoses/diagnóstico por imagem , Animais , Líquido Cístico/química , DNA de Helmintos/química , Equinococose Hepática/parasitologia , Echinococcus granulosus/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Humanos , Mitocôndrias/enzimologia , Filogenia , Reação em Cadeia da Polimerase , Análise Espectral Raman , Zoonoses/parasitologia
7.
J Parasitol ; 105(5): 783-792, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31633437

RESUMO

The nematode genus Bidigiticauda has 2 species (Bidigiticauda vivipara and Bidigiticauda embryophilum), which are parasites of bats from the Neotropical region. The present paper describes a new species of Bidigiticauda from a male Artibeus planirostris specimen collected in the Pratigi Environmental Protection Area in Bahia state, Brazil. The new species, Bidigiticauda serrafreirei n. sp., differs from B. embryophilum by having longer spicules, rays 5 and 6 arising from a common trunk and bifurcating in its first third, rays 3 and 4 emerging slightly separated from each other, and dorsal rays reaching the margin of the caudal bursa. The new species also differs from B. vivipara by the dorsal ray bifurcating at the extremity of the trunk. A molecular phylogenetic analysis was conducted to determine the evolutionary affinities of Bidigiticauda serrafreirei n. sp. within the Strongylida, which identified a clade that grouped Bidigiticauda with the other members of the Anoplostrongylinae. However, the molineid subfamilies did not group together, indicating that the family Molineidae is polyphyletic. Further analyses, which include additional taxa and genetic markers, should elucidate the complex relationships within the Molineidae, in particular its subfamilies and the evolution of the traits that define these groups.


Assuntos
Quirópteros/parasitologia , Filogenia , Trichostrongyloidea/classificação , Tricostrongiloidíase/veterinária , Animais , Teorema de Bayes , Brasil , Código de Barras de DNA Taxonômico/veterinária , DNA de Helmintos/química , DNA de Helmintos/isolamento & purificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Florestas , Masculino , Mitocôndrias/enzimologia , RNA Ribossômico 28S/genética , Trichostrongyloidea/anatomia & histologia , Trichostrongyloidea/genética , Trichostrongyloidea/isolamento & purificação , Tricostrongiloidíase/parasitologia
8.
Vet Parasitol Reg Stud Reports ; 17: 100295, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31303226

RESUMO

Information pertaining to parasitic fauna and parasitic diseases in Manipuri ponies in India is not available. Moreover, no systematic studies have been undertaken on cutaneous habronemosis in Manipuri ponies which is a common skin problem of Manipuri ponies as reported by pony owners. Keeping in the view of the importance of parasitic infections in veterinary health coverage particularly in Manipuri ponies, the present study was planned. A survey of natural cases of cutaneous habronemosis followed by molecular confirmation of species involved and treatments were done. Out of 200 ponies examined, nine cases (4.5%) of cutaneous habronemosis was recorded. Gross examination revealed raised and ulcerated wounds with necrotic tissues covered with yellowish-tan granulation. Histopathological study revealed eosinophilic granuloma and in the center of the granuloma with necrotic debris. Remnants of the Hebronema larvae with infiltrating neutrophils surrounded by proliferating fibrous tissue with numerous eosinophils, macrophages and lymphocytes were also observed. Molecular detection of Habronema sp. was confirmed by semi-nested PCR. Sequence analysis revealed larvae of H. muscae was the common spirurid species responsible for producing cutaneous habronemosis in Manipuri ponies. Subsequently, sequence submitted to NCBI GenBank and accession number obtained (MH038181). Surgical removal of necrotic tissue, ivermectin injection along with antibiotics successfully cured all the lesions in infected ponies.Results confirmed occurrence of cutaneous habronemosis in Manipuri ponies in India.


Assuntos
Doenças dos Cavalos/epidemiologia , Doenças dos Cavalos/parasitologia , Dermatopatias Parasitárias/veterinária , Infecções por Spirurida/veterinária , Spiruroidea/genética , Combinação Amoxicilina e Clavulanato de Potássio/administração & dosagem , Animais , Antiparasitários/administração & dosagem , Sequência de Bases , Biópsia/veterinária , Clonagem Molecular , DNA de Helmintos/química , DNA de Helmintos/isolamento & purificação , DNA Ribossômico/química , DNA Ribossômico/genética , Granuloma Eosinófilo/parasitologia , Granuloma Eosinófilo/patologia , Granuloma Eosinófilo/veterinária , Fezes/parasitologia , Feminino , Doenças dos Cavalos/patologia , Doenças dos Cavalos/terapia , Cavalos , Incidência , Índia/epidemiologia , Ivermectina/administração & dosagem , Masculino , Necrose/veterinária , Reação em Cadeia da Polimerase , Alinhamento de Sequência/veterinária , Dermatopatias Parasitárias/epidemiologia , Dermatopatias Parasitárias/parasitologia , Dermatopatias Parasitárias/patologia , Infecções por Spirurida/epidemiologia , Infecções por Spirurida/parasitologia , Infecções por Spirurida/patologia , Spiruroidea/isolamento & purificação
9.
J Parasitol ; 105(4): 524-532, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31298617

RESUMO

A new species of nematode, Ascarophis morronei n. sp. (Cystidicolidae), is described from the stomach wall of the woolly sculpin Clinocottus analis (Cottidae) collected in the rocky intertidal from northwestern Baja California, Mexico. Collected nematodes were studied using both light and scanning electron microscopy. Sequence fragments for 18S rDNA molecular markers were obtained from the new nematode species, in order to test its position within the family Cystidicolidae under a phylogenetic context. Main characters distinguishing this new species include the reduced labia and the morphology of the eggs, distances of nerve ring and excretory pore from the anterior end, and left spicule of males. The new species described here is the second for the genus Ascarophis reported as adult in the Southern California Bight, and the first one recorded for the fish genus Clinocottus.


Assuntos
Doenças dos Peixes/parasitologia , Perciformes/parasitologia , Infecções por Spirurida/veterinária , Spiruroidea/classificação , Animais , Teorema de Bayes , Sequência Consenso , DNA de Helmintos/química , DNA de Helmintos/genética , DNA de Helmintos/isolamento & purificação , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Ribossômico/isolamento & purificação , Feminino , Doenças dos Peixes/epidemiologia , Masculino , México/epidemiologia , Filogenia , Reação em Cadeia da Polimerase/veterinária , Infecções por Spirurida/epidemiologia , Infecções por Spirurida/parasitologia , Spiruroidea/genética , Spiruroidea/isolamento & purificação , Spiruroidea/ultraestrutura , Estômago/parasitologia
10.
Exp Parasitol ; 200: 42-47, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30922888

RESUMO

In order to develop a method of identification and discrimination of Echinococcus granulosus sensu stricto from faecal samples of dogs infected with taeniid eggs (Echinococcus spp., Taenia spp.), a combined strategy of Polymerase Chain Reaction (PCR) and Restriction Fragments of Lenght Polymorphisms (RFLP) was proposed. Initially, a pair of primers was designed to amplify a fragment of the 12 Subunit of ribosomal RNA gene (12SrRNA) from mitochondrial DNA. The amplified product was digested by SspI restriction enzyme, which in E. granulosus kept the intact fragment of 160 basis pairs (bp), while in Taenia spp. produced two fragments (62 bp and another of 98 bp). The method was tested using positive controls of DNA, in faecal samples experimentally contaminated with eggs of E. granulosus and Taenia spp. and in dogs naturally infected. In all of them, reproducible results were obtained and the primers were specific to amplify only Taeniidae DNA. The sensitivity of the technique was tested, achieving amplification of DNA extractions with a single egg. In conclusion, the technique developed was optimal and easy to identify patent infections by E. granulosus s.s., constituting a possible alternative for epidemiological studies in dogs, especially in endemic areas where this infection occurs.


Assuntos
Doenças do Cão/parasitologia , Equinococose/veterinária , Echinococcus granulosus/isolamento & purificação , Fezes/parasitologia , Taenia/isolamento & purificação , Teníase/veterinária , Animais , Sequência de Bases , Sequência Consenso , DNA de Helmintos/química , Cães , Equinococose/parasitologia , Echinococcus granulosus/genética , Reação em Cadeia da Polimerase/veterinária , Polimorfismo de Fragmento de Restrição , Sensibilidade e Especificidade , Alinhamento de Sequência/veterinária , Taenia/genética , Teníase/parasitologia
11.
Exp Parasitol ; 198: 1-6, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30633913

RESUMO

The in vitro effect of progesterone in T. canis larvae on their enlargement and motility were evaluated, together to the possible presence of progesterone receptors (PRs). T. canis larvae were cultured in RPMI-1640 with different concentrations of progesterone (0, 20, 40, 80, 400 and 800 ng/mL). Enlargement and increases in motility were dependent on the concentration only from 0 to 80 ng/mL (p < 0.05). The mean percentage of PR + cells in newly obtained larvae as measured by flow cytometry was 8.16 ± 0.4. The number of PR + cells increased depending on concentration from 0 to 80 ng/mL (p < 0.001). Cells obtained from larvae stimulated at any of the studied hormone concentrations showed greater mean fluorescence intensity when compared to non-stimulated cells. Additionally, the expression and location of PR + cells were determined in the larvae. The sequence of an amplicon (420-bp) obtained by PCR from T. canis larvae showed 100% homology with a gene fragment that codes for the PR of the dog. PR + cells were immunolocated using confocal microscopy in the intestinal region of the larvae that had been recently obtained. The results of this study show that T. canis larvae can recognize and respond to the presence of progesterone through a molecule possibly able to bind it. Since we previously observed a similar response to prolactin, we suggest that both hormones could participate sequentially in the reactivation of T. canis larvae in pregnant bitches.


Assuntos
Progesterona/farmacologia , Progestinas/farmacologia , Receptores de Progesterona/efeitos dos fármacos , Toxocara canis/efeitos dos fármacos , Animais , Sequência de Bases , DNA de Helmintos/química , DNA de Helmintos/isolamento & purificação , Cães , Feminino , Citometria de Fluxo , Intestinos/parasitologia , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/fisiologia , Camundongos , Microscopia Confocal , Movimento/efeitos dos fármacos , Reação em Cadeia da Polimerase , Receptores de Progesterona/análise , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Toxocara canis/crescimento & desenvolvimento , Toxocara canis/fisiologia
12.
Plant Dis ; 102(11): 2101-2111, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30169136

RESUMO

Stubby root nematodes (SRN) are important plant parasites infecting many crops and widely distributed in many regions of the United States. SRN transmit Tobacco rattle virus, which causes potato corky ringspot disease, thereby having a significant economic impact on the potato industry. In 2015 to 2017, 184 soil samples and 16 nematode suspensions from North Dakota, Minnesota, Idaho, Oregon, Washington, South Carolina, North Carolina, and Florida were assayed for the presence of SRN. SRN were found in 106 soil samples with population densities of 10 to 320 SRN per 200 g of soil and in eight of the nematode suspensions. Sequencing of ribosomal DNA (rDNA) or species-specific polymerase chain reaction assays revealed the presence of four SRN species, including Paratrichodorus allius, P. minor, P. porosus, and Trichodorus obtusus. Accordingly, their rDNA sequences were characterized by analyzing D2-D3 of 28S rDNA, 18S rDNA, and internal transcribed spacer (ITS) rDNA obtained in this study and retrieved from GenBank. Both intra- and interspecies variations were higher in ITS rDNA than 18S rDNA and D2-D3 of 28S rDNA. Based on phylogenetic analysis, the four SRN species formed a monophyletic group, with P. allius more closely related to P. porosus than P. minor and T. obtusus. Indel variation of ITS2 rDNA was present in P. allius populations from the same geographic regions. This study documented the occurrence of SRN species across multiple states. The intra- and interspecies genetic diversity of rDNA in this study will provide more information for understanding the evolutionary relationships of SRN and will be valuable for future studies of SRN species identification and management.


Assuntos
Produtos Agrícolas/parasitologia , Variação Genética , Nematoides/genética , Doenças das Plantas/parasitologia , Animais , Beta vulgaris/parasitologia , DNA de Helmintos/química , DNA de Helmintos/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Meio-Oeste dos Estados Unidos , Nematoides/isolamento & purificação , Noroeste dos Estados Unidos , Pisum sativum/parasitologia , Filogenia , Alinhamento de Sequência , Solo/parasitologia , Solanum tuberosum/parasitologia , Sudeste dos Estados Unidos , Especificidade da Espécie
13.
J Parasitol ; 104(2): 117-132, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29231789

RESUMO

Adult and cystacanth forms of the acanthocephalan Serrasentis sagittifer from Australian coastal waters are redescribed and verified as the same species using both molecular and morphological data. This study provides the baseline 18S rDNA, 28S rDNA, and cox1 sequence data to serve as genetic barcode for S. sagittifer. The validity of the currently recognized species of Serrasentis is discussed. The most recently described species are junior synonyms of either Serrasentis nadakali or S. sagittifer, and a number of species are species inquirenda. When using morphological characters to distinguish the species of Serrasentis, consideration needs to be given to the maturity of the specimens, since the trunk elongates and the number and distribution of the ventral combs changes as worms mature, although the proboscis armature itself does not change. A simple key to assist in the identification of species of Serrasentis is provided. Adult S. sagittifer appear to be highly host specific to the cobia, Rachycentron canadum, in northern Australian waters, whereas cystacanths have been reported from a wide range of fish species. The relationship between host length and number of cystacanths shows that most paratenic infections are acquired as young fish, most likely via a crustacean intermediate host.


Assuntos
Acantocéfalos/anatomia & histologia , Acantocéfalos/classificação , Doenças dos Peixes/parasitologia , Helmintíase Animal/parasitologia , Acantocéfalos/genética , Acantocéfalos/crescimento & desenvolvimento , Animais , Austrália , Sequência de Bases , Sequência Consenso , DNA de Helmintos/química , DNA de Helmintos/isolamento & purificação , DNA Ribossômico/química , Feminino , Peixes , Interações Hospedeiro-Parasita , Oceano Índico , Funções Verossimilhança , Masculino , Oceano Pacífico , Filogenia , Alinhamento de Sequência
14.
Exp Parasitol ; 183: 50-55, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29024693

RESUMO

Echinococcus granulosus is now considered a complex consisting of at least four species and ten genotypes. Different molecular targets have been described for molecular characterization of E. granulosus; however, in almost all studies only one or two of the targets have been used, and only limited data is available on the utilization of multiple loci. Therefore, we investigated the genetic diversity among 64 strains isolated from 138 cyst specimens of human and animal isolates, using a set of nuclear and mitochondrial genes; i.e., cytochrome c oxidase subunit 1 (cox1), NADH dehydrogenase subunit 1 (nad1), ATPase subunit 6 (atp6), 12S rRNA (12S), and Actin II (act II). In comparison to the use of molecular reference targets (nad1 + cox1), using singular target (act II or 12S or atp6) yielded lower discriminatory power. Act II and 12S genes could accurately discriminate the G6 genotype, but they were not able to differentiate between G1 and G3 genotypes. As the G1 and G3 genotypes belong to the E. granulosus sensu stricto, low intra-species variation was observed for act II and 12S. The atp6 gene could identify the G3 genotype but could not differentiate G6 and G1 genotypes. Using concatenated sequence of five genes (cox1 + nad1 + atp6 + 12S + act II), genotypes were identified accurately, and markedly higher resolution was obtained in comparison with the use of reference markers (nad1 + cox1) only. Application of multilocus sequence analysis (MLSA) to large-scale studies could provide valuable epidemiological data to make efficient control and management measures for cystic echinococcosis.


Assuntos
Equinococose/parasitologia , Echinococcus granulosus/genética , Animais , Búfalos , Bovinos , DNA de Helmintos/química , DNA de Helmintos/isolamento & purificação , Equinococose/epidemiologia , Echinococcus granulosus/classificação , Echinococcus granulosus/fisiologia , Marcadores Genéticos , Variação Genética , Genótipo , Cabras , Coração/parasitologia , Especificidade de Hospedeiro , Humanos , Irã (Geográfico)/epidemiologia , Fígado/parasitologia , Pulmão/parasitologia , Tipagem de Sequências Multilocus , Filogenia , Ovinos , Baço/parasitologia
15.
J Parasitol ; 103(3): 268-284, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28350489

RESUMO

Much progress has recently been made in revising the taxonomic assignments of genera originally classified in the polyphyletic "Tetraphyllidea." Many of these genera, including Echeneibothrium, were accommodated in the order Rhinebothriidea. However, beyond this larger taxonomic action, little work has been conducted on this genus over the past 50 yr. Consequently, the criteria used for characterizing species of Echeneibothrium have lagged behind those typically used in more modern descriptions of elasmobranch-hosted cestode taxa. A series of collecting trips to Chile to obtain cestodes from the yellownose skate, Dipturus chilensis , provided a unique opportunity to apply modern morphological and molecular methods to investigate the 3 species of Echeneibothrium reported parasitizing this skate, specifically Echeneibothrium megalosoma, Echeneibothrium multiloculatum, and Echeneibothrium williamsi. In addition to redescribing all 3 species, using morphological data from light and scanning electron microscopy, maximum likelihood and bayesian inference phylogenetic analyses of the D1-D3 regions of the 28S rDNA gene were conducted to assess their relationships among other echeneibothriids for which comparable data are available. Sequencing of 59 specimens representing these 3 species of Echeneibothrium allowed us to assess the intra- and interspecific variation in the 28S rDNA gene. The redescriptions use standardized terminology for scolex morphology, proglottid anatomy, and microthrix forms and pattern; they also expand on the original descriptions to include data on scolex size, ovary size, vas deferens and vaginal configurations, testes arrangement, and genital pore position. Our morphological work led to a major reinterpretation of the scolex morphology with the recognition that all 3 species bear an apical bothridial sucker, rather than an apical loculus, prompting emendation of the diagnosis for the family Echeneibothriidae. The presence of a band of spinitriches at the apex of the apical modification of the scolex proper seems to represent an important feature for distinguishing the 2 portions of the myzorhynchus across species. Intraspecific variation ranged from 0 to 7 bp across species and interspecific variation ranged from a low of 39-46 bp between E. williamsi and E. multiloculatum to a high of 61-66 bp between E. multiloculatum and E. megalosoma. Phylogenetic analyses indicate that the 3 species of Echeneibothrium hosted by the yellownose skate are not each other's closest relatives, suggesting multiple colonization events of D. chilensis have occurred. Further phylogenetic investigation is also likely to confirm the status of the genus Pseudanthobothrium as a synonym of Echeneibothrium because its species generally group among members of Echeneibothrium.


Assuntos
Cestoides/classificação , Infecções por Cestoides/veterinária , Doenças dos Peixes/parasitologia , Rajidae/parasitologia , Animais , Cestoides/genética , Cestoides/ultraestrutura , Infecções por Cestoides/epidemiologia , Infecções por Cestoides/parasitologia , Chile/epidemiologia , DNA de Helmintos/química , DNA de Helmintos/isolamento & purificação , DNA Ribossômico/química , Doenças dos Peixes/epidemiologia , Intestinos/parasitologia , Funções Verossimilhança , Microscopia Eletrônica de Varredura/veterinária , Oceano Pacífico/epidemiologia , Filogenia , Reação em Cadeia da Polimerase , Prevalência , RNA Ribossômico 28S/genética
16.
Korean J Parasitol ; 55(1): 65-69, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28285508

RESUMO

A case of Taenia asiatica infection detected by small bowel series and colonoscopy is described. The patient was a 42-year-old Korean man accompanied by discharge of movable proglottids via anus. He used to eat raw pig liver but seldom ate beef. Small bowel series radiologic examinations showed flat tape-like filling defects on the ileum. By colonoscopy, a moving flat tapeworm was observed from the terminal ileum to the ascending colon. The tapeworm was identified as T. asiatica by mitochondrial DNA sequencing. The patient was prescribed with a single oral dose (16 mg/kg) of praziquantel.


Assuntos
Colonoscopia , Taenia/isolamento & purificação , Teníase/diagnóstico , Animais , Sequência de Bases , Colo/parasitologia , Colo/patologia , DNA de Helmintos/química , DNA de Helmintos/genética , DNA Mitocondrial/química , DNA Mitocondrial/genética , Comportamento Alimentar , Humanos , Íleo/diagnóstico por imagem , Íleo/parasitologia , Íleo/patologia , Coreia (Geográfico) , Masculino , Dados de Sequência Molecular , Radiografia Abdominal , Alinhamento de Sequência , Análise de Sequência de DNA , Taenia/classificação , Taenia/genética , Teníase/parasitologia
17.
Exp Parasitol ; 176: 75-81, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28238686

RESUMO

The full cDNA of Mi-ace-3 encoding an acetylcholinesterase (AChE) in Meloidogyne incognita was cloned and characterized. Mi-ace-3 had an open reading frame of 1875 bp encoding 624 amino acid residues. Key residues essential to AChE structure and function were conserved. The deduced Mi-ACE-3 protein sequence had 72% amino acid similarity with that of Ditylenchus destructor Dd-AChE-3. Phylogenetic analyses using 41 AChEs from 24 species showed that Mi-ACE-3 formed a cluster with 4 other nematode AChEs. Our results revealed that the Mi-ace-3 cloned in this study, which is orthologous to Caenorhabditis elegans AChE, belongs to the nematode ACE-3/4 subgroup. There was a significant reduction in the number of galls in transgenic tobacco roots when Mi-ace-1, Mi-ace-2, and Mi-ace-3 were knocked down simultaneously, whereas little or no effect were observed when only one or two of these genes were knocked down. This is an indication that the functions of these three genes are redundant.


Assuntos
Acetilcolinesterase/genética , Evolução Molecular , Regulação Enzimológica da Expressão Gênica , Tylenchoidea/genética , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Sequência de Aminoácidos , Animais , Clonagem Molecular , DNA Complementar/química , DNA Complementar/genética , DNA de Helmintos/química , DNA de Helmintos/genética , Técnicas de Silenciamento de Genes , Solanum lycopersicum/parasitologia , Técnicas de Amplificação de Ácido Nucleico , Fases de Leitura Aberta , Filogenia , Raízes de Plantas/parasitologia , Tumores de Planta/genética , Tumores de Planta/parasitologia , Interferência de RNA/fisiologia , Nicotiana/enzimologia , Nicotiana/genética , Nicotiana/parasitologia , Tylenchoidea/classificação , Tylenchoidea/enzimologia
18.
Exp Parasitol ; 171: 77-83, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27810319

RESUMO

In genetic diversity and population structure of Echinococcus granulosus, the gene flow can illustrate how the Echinococcus isolates have epidemiologically drifted among endemic neighboring countries. 51 isolates of hydatid cysts were collected from human, dog, cattle and sheep in northwest Iran, where placed co-border with Turkey. DNA samples were extracted, amplified and subjected to sequence analysis of NADH dehydrogenase subunit 1 (nad1) and cytochrome oxidase subunit 1 (cox1) genes. As well, sequences of Echinococcus at east to the southeast regions of Turkey were retrieved from GenBank database for the cox1 gene. The confirmed isolates were grouped as G1 (n = 74) and G3 (n = 6) genotypes. 31 unique haplotypes were identified inferred by the analyzed sequences of cox1 among two distinct populations. A parsimonious network of the sequence haplotypes displayed star-like features in the overall population containing TUR1, IR15 and IR22 as the most common haplotypes. According to AMOVA test, the high value of haplotype diversity (0.94758-0.98901) of E. granulosus was reflected the total genetic variability within populations while nucleotide diversity was low (0.00727-0.01046) in Iranian and Turkish metapopulations. Neutrality indices of the cox1 were shown negative values (-15.078 to -10.057) in Echinococcus populations which indicating a significant divergence from neutrality. A pairwise fixation index (Fst) as a degree of gene flow was partially high value for all populations (0.151). The statistically Fst value indicates that E. granulosus sensu stricto (G1-G3) are genetically moderate differentiated among Iranian and Turkish isolates. The occurrence of TUR1 and IR15 elucidate that there is possibly the dawn of domestication due to transfer of alleles between populations through the diffusion of stock raising or anthropogenic movements. To evaluate the hypothetical evolutionary scenario, further exploration is necessitated to analyze isolates from various host species in rest Middle East countries.


Assuntos
Equinococose/epidemiologia , Echinococcus granulosus/genética , Fluxo Gênico , Deriva Genética , Variação Genética , Animais , Sequência de Bases , Bovinos , Ciclo-Oxigenase 1/química , Ciclo-Oxigenase 1/genética , DNA de Helmintos/química , DNA de Helmintos/isolamento & purificação , DNA Mitocondrial/química , Cães , Equinococose/parasitologia , Echinococcus granulosus/classificação , Doenças Endêmicas , Genótipo , Haplótipos , Humanos , Irã (Geográfico)/epidemiologia , Filogenia , Análise de Sequência de DNA , Ovinos , Turquia/epidemiologia
20.
Acta Trop ; 164: 125-136, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27619188

RESUMO

Fork head box transcription factors subfamily O (FoxO) is regarded to be significant in cell-cycle control, cell differentiation, ageing, stress response, apoptosis, tumour formation and DNA damage repair. In the free-living nematode Caenorhabditis elegans, the FoxO transcription factor is encoded by Ce-daf-16, which is negatively regulated by insulin-like signaling (IIS) and involved in promoting dauer formation through bringing about its hundreds of downstream genes expression. In nematode parasites, orthologues of daf-16 from several species have been identified, with functions in rescue of dauer phenotypes determined in a surrogate system C. elegans. In this study, we identified the FoxO encoding gene, Acan-daf-16, from the parasitic nematode Angiostrongylus cantonensis, and determined the genomic structures, transcripts and functions far more thorough in longevity, stress resistance and dauer formation. Acan-daf-16 encodes two proteins, Acan-DAF-16A and Acan-DAF-16B, consisting of 555 and 491 amino acids, respectively. Both isoforms possess the highly conserved fork head domains. Acan-daf-16A and Acan-daf-16B are expressed from distinct promoters. The expression patterns of Acan-daf-16 isoforms in the C. elegans surrogate system showed that p Acan-daf-16a:gfp was expressed in all cells of C. elegans, including the pharynx, and the expression of p Acan-daf-16b:gfp was restricted to the pharynx. In addition to the same genomic organization to the orthologue in C. elegans, Ce-daf-16, both Acan-DAF-16 isoforms could restore the C. elegans daf-16(mg54) mutation in longevity, dauer formation and stress resistance, in spite of the partial complementation of Acan-DAF-16B isoform in longevity. These findings provide further evidence of the functional conservation of DAF-16s between parasitic nematodes and the free-living nematode C. elegans.


Assuntos
Angiostrongylus cantonensis/genética , Fatores de Transcrição Forkhead , Sequência de Aminoácidos , Animais , DNA de Helmintos/química , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Dados de Sequência Molecular , Ratos , Ratos Sprague-Dawley , Homologia de Sequência de Aminoácidos
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