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1.
Parasite ; 26: 43, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31335314

RESUMO

Neoechinorhynchus (Neoechinorhynchus) johnii Yamaguti, 1939 is redescribed from Eleutheronema tetradactylum (Polynemidae), Johnius carouna (Sciaenidae), Johnius sp., and Otolithes ruber (Sciaenidae) along the north and south coasts of Vietnam. Our description completes missing and inadequate information in the original descriptions and line drawings from Johnius goma in Japan and from Pseudosciaena diacanthus in the Indian Ocean. We add new information documented by scanning electron microscopy (SEM) and photomicroscopy, and explore the wide morphological diversity attributed to host species. The redescription includes: worms cylindrical with round proboscis with prominent apical organ, and large anterior hooks distant from small middle and posterior hooks; neck longer than the proboscis, nucleated lemnisci subequal, and receptacle with large basal triangulate cephalic ganglion and attached para-receptacle structure (PRS); male reproductive system in posterior half of trunk; adult females with introvert genital vestibule; and eggs spherical or rectangular. Gallium cuts and X-ray scans of hooks show high concentrations of sulfur on edge layer aiding in forming hardened calcium phosphate apatite of that layer with calcium and phosphorus in higher concentration in central part of hook. Molecular results consistently yielded a strongly supported distinct clade for the Neoechinorhynchus species from Vietnam for both 18S gene and the ITS1-5.8S-ITS2 region of ribosomal RNA. Phylogenetic analysis demonstrated that N. johnii occupies a separate position in the trees, probably indicating an Asian origin of this species.


Assuntos
Acantocéfalos/anatomia & histologia , Acantocéfalos/classificação , Doenças dos Peixes/parasitologia , Peixes/parasitologia , Filogenia , Acantocéfalos/ultraestrutura , Animais , DNA Intergênico/genética , Feminino , Genitália/ultraestrutura , Helmintíase Animal , Masculino , Microscopia Eletrônica de Varredura , Oceano Pacífico , RNA Ribossômico 18S/genética , Vietnã
2.
Parasit Vectors ; 12(1): 351, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31307517

RESUMO

BACKGROUND: Anopheles maculatus (s.s.) is an important vector of malaria in Indonesia. Previously it was considered the only member of the Maculatus Group present in Indonesia. A novel species was recently identified in the Kulon Progo District in Central Java. Until recently, few investigations have been conducted looking at An. maculatus genetic diversity in Indonesia, including allopatric island populations. METHODS: Indonesian An. maculatus (s.l.) samples were collected in several locations in Java, Lesser Sunda Island group, Sumatra and in Kulon Progo (Yogyakarta, central Java) where a novel species has been identified. Samples from a 30-year-old colony of the Kulon Progo population were also included in the analysis. Maximum-likelihood analysis established the phylogenies of the ITS2 (nuclear) and cox1 (mitochondrial) markers. Putative times of separation were based on cox1 genetic distances. RESULTS: Two species of the Maculatus Group are present in Indonesia. The novel sibling species is more closely related to Anopheles dispar than to An. maculatus (s.s.). Anopheles maculatus (s.s.) samples are homogeneous based on the ITS2 sequences. Indonesian samples and An. dispar belong to the same cox1 maternal lineage and differ from all other known members of the Maculatus Group. Divergence time between the different populations found in Java was estimated using an established cox1 mutation rate. CONCLUSIONS: A novel species within the Maculatus Group, most closely related to An. dispar, is confirmed present in the Kulon Progo area of Central Java. The divergence of this species from An. maculatus (s.s.) is explained by the stable refugia in the Kulon Progo area during the quaternary period of intense volcanic activity throughout most of Java. This novel species awaits detailed morphological description before applying a formal species name. For the interim, it is proposed that the Kulon Progo population be designated An. maculatus var. menoreh to distinguish it from An. maculatus (s.s.).


Assuntos
Anopheles/classificação , Variação Genética , Filogenia , Animais , Ciclo-Oxigenase 1/genética , DNA Intergênico/genética , Indonésia , Ilhas , Malária/transmissão , Mosquitos Vetores/classificação , Mutação
3.
Parasit Vectors ; 12(1): 360, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31340841

RESUMO

BACKGROUND: Perkinsosis, a disease caused by the protist Perkinsus, is responsible for mass mortalities of many molluscan species worldwide. The rapid, early and accurate detection of Perkinsus infection is necessary to react to outbreaks, and manage disease transmission. Current methods for diagnosis of Perkinsus spp. are time-consuming or require professional equipment and experienced personnel, rendering them unsuitable for field application. Recombinase polymerase amplification (RPA) assay is a highly sensitive and selective isothermal amplification technique that operates at temperatures of 37-42 °C, requires minimal sample preparation, and is capable of amplifying as low as 1-10 target DNA copies in less than 20 minutes. METHODS: We report a novel RPA assay that amplifies the internal transcriber spacer (ITS) region of P. beihaiensis, which, followed by rapid detection of amplicons using a lateral flow (LF) strip, enables easy visualization of results by the naked eye. RESULTS: The LF-RPA assay successfully amplified P. beihaiensis DNA using a set of primers of 20-25 bp in length. After incubation at 37 °C for 25 min, results were read within 5 min by the naked eye on a lateral flow strip. Our LF-RPA assay was comparably sensitive to qPCR assay, and capable of detecting as few as 26 copies of P. beihaiensis DNA. Cross-amplification occurred with other two Perkinsus species, P. olseni and P. chesapeaki, but not with other potential pathogen taxa in culture environments. We compared the performance of LF-RPA, conventional PCR and qPCR assays on 60 oyster samples. While LF-RPA assay results were 86.2% as sensitive, 77.4% as specific, and generally in agreement with those of conventional PCR results, they were more (93.3%) sensitive, (86.7%) specific, and agreed better with qPCR assay results. Future research should focus on developing simple DNA extraction methods that do not require professional laboratories and complicated extraction procedures, to facilitate application of this LF-RPA assay in the field. CONCLUSIONS: Our LF-RPA assay provides a rapid and efficient method for detecting species of Perkinsus. This novel assay has potential to be used in field applications.


Assuntos
Alveolados/isolamento & purificação , Crassostrea/parasitologia , Técnicas de Amplificação de Ácido Nucleico/métodos , Infecções Protozoárias em Animais/diagnóstico , Alveolados/genética , Animais , Primers do DNA/genética , DNA Intergênico/genética , Visualização de Dados , Eletroforese em Gel de Ágar , Reação em Cadeia da Polimerase/métodos , Infecções por Protozoários , Recombinases/genética , Sensibilidade e Especificidade
4.
BMC Evol Biol ; 19(1): 145, 2019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31311504

RESUMO

BACKGROUND: China is an important biogeographical zone in which the genetic legacies of the Tertiary and Quaternary periods are abundant, and the contemporary geography environment plays an important role in species distribution. Therefore, many biogeographical studies have focused on the organisms of the region, especially zooplankton, which is essential in the formation of biogeographical principles. Moreover, the generality of endemism also reinforces the need for detailed regional studies of zooplankton. Bosmina, a group of cosmopolitan zooplankton, is difficult to identify by morphology, and no genetic data are available to date to assess this species complex in China. In this study, 48 waterbodies were sampled covering a large geographical and ecological range in China, the goal of this research is to explore the species distribution of Bosmina across China and to reveal the genetic information of this species complex, based on two genetic markers (a mtDNA 16S and a nuclear ITS). The diversity of taxa in the Bosmina across China was investigated using molecular tools for the first time. RESULTS: Two main species were detected in 35 waterbodies: an endemic east Asia B. fatalis, and the B. longirostris that has a Holarctic distribution. B. fatalis had lower genetic polymorphism and population differentiation than B. longirostris. B. fatalis was preponderant in central and eastern China, whereas B. longirostris was dominated in western China. The third lineage (B. hagmanni) was only detected in a reservoir (CJR) of eastern China (Guangdong province). Bosmina had limited distribution on the Tibetan plateau. CONCLUSIONS: This study revealed that the biogeography of Bosmina appear to be affected by historical events (Pleistocene glaciations) and contemporary environment (such as altitude, eutrophication and isolated habitat).


Assuntos
Cladóceros/genética , DNA Intergênico/genética , DNA Mitocondrial/genética , Variação Genética , Animais , Núcleo Celular/genética , China , Ecossistema , Marcadores Genéticos , Geografia , Haplótipos/genética , Funções Verossimilhança , Mitocôndrias/genética , Filogenia , Polimorfismo Genético , Zooplâncton/genética
5.
Parasitol Res ; 118(7): 2159-2168, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31165239

RESUMO

Terranova pectinolabiata n. sp. is described from the great hammerhead, Sphyrna mokarran, from Australian waters. This represents the first report of a species of Terranova from the host species. The new species is characterised by the morphology of the caudal plates and labia. ITS sequences were obtained for 20 specimens which were identical, despite morphological variation that has traditionally been indicative of separation of species. Additionally, genetic analyses confirmed the identification of the larval Terranova Type II previously reported in Australian and New Caledonian waters as Terranova pectinolabiata n. sp.


Assuntos
Ascaridoidea/classificação , Ascaridoidea/genética , Tubarões/parasitologia , Animais , Ascaridoidea/isolamento & purificação , Austrália , DNA Intergênico/genética , Larva/genética
6.
Parasitol Res ; 118(7): 2213-2221, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31183599

RESUMO

The Centrorhynchidae (Acanthocephala: Palaeacanthocephala) is a cosmopolitan family commonly found in various avian and mammalian hosts. Within Centrorhynchidae, species of the genus Sphaerirostris Golvan, 1956 are usually parasitic in the digestive tract of various passerine birds. In the present study, adult specimens of Sphaerirostris picae (Rudolphi, 1819), the type species of this genus, were recovered from the small intestine of Acridotheres tristis (Sturnidae) and Dendrocitta vagabunda (Corvidae) in Pakistan. Molecular data from the nuclear or mitochondrial genome is either very limited or completely absent from this phylogenetically understudied group of acanthocephalans. To fill this knowledge gap, we sequenced and determined the internal transcribed spacers of ribosomal DNA (ITS rDNA) and the complete mitochondrial (mt) genome of S. picae. The ITS rDNA of S. picae was 95.2% similar to that of Sphaerirostris lanceoides which is the only member of the Centrorhynchidae whose ITS rDNA is available in GenBank. The phylogenetic tree based on the amino acid sequences of 12 mt protein-coding genes (PCGs) placed S. picae close to Centrorhynchus aluconis in a monophyletic clade of Polymorphida which also contain members of the families Polymorphidae and Plagiorhynchidae on separate branches. The mt gene arrangement, nucleotide composition and codon usage of 12 PCGs were discussed and compared with those of other acanthocephalan mt genomes. Within the Centrorhynchidae, S. picae and C. aluconis showed 67.7-86.8% similarity in the nucleotide sequences of 12 PCGs and 2 rRNAs, where nad4L is the most conserved gene while atp6 is the least conserved. The similarity in amino acid sequences ranged from 68.1 to 91.8%, where cox1 was recorded as the most conserved gene, while atp6 is highly variable among 12 PCGs. This novel mt genome of S. picae provides genetic resources for further studies of phylogenetics and molecular epidemiology of acanthocephalans.


Assuntos
Acantocéfalos/classificação , Acantocéfalos/genética , DNA Mitocondrial/genética , Genoma Mitocondrial/genética , Intestino Delgado/parasitologia , Passeriformes/parasitologia , Sequência de Aminoácidos/genética , Animais , Sequência de Bases , ATPases Transportadoras de Cálcio/genética , Ciclo-Oxigenase 1/genética , DNA Intergênico/genética , DNA de Protozoário/genética , DNA Ribossômico/genética , Paquistão , Filogenia , RNA Ribossômico/genética
7.
J Plant Res ; 132(4): 461-471, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31115709

RESUMO

Reproductive isolation, including prezygotic and postzygotic barriers, is a mechanism that separates species. Many species in the Nicotiana section Suaveolentes exhibit reproductive isolation in crosses with Nicotiana tabacum. In this study, we investigated whether the chromosome numbers and ploidy levels of eight Nicotiana suaveolens accessions are related to the reproductive isolation after crosses with N. tabacum by flow cytometry and chromosome analyses. Additionally, the internal transcribed spacer (ITS) regions of the eight N. suaveolens accessions were sequenced and compared with the previously reported sequences of 22 Suaveolentes species to elucidate the phylogenetic relationships in the section Suaveolentes. We revealed that four N. suaveolens accessions comprised 64 chromosomes, while the other four accessions carried 32 chromosomes. Depending on the ploidy levels of N. suaveolens, several types of reproductive isolation were observed after crosses with N. tabacum, including decreases in the number of capsules and the germination rates of hybrid seeds, as well as hybrid lethality and abscission of enlarged ovaries at 12-17 days after pollination. A phylogenetic analysis involving ITS sequences divided the eight N. suaveolens accessions into three distinct clades. Based on the results, we confirmed that N. suaveolens accessions vary regarding ploidy levels and reproductive isolation mechanisms in crosses with N. tabacum. These accessions will be very useful for revealing and characterizing the reproductive isolation mechanisms in interspecific crosses and their relationships with ploidy levels.


Assuntos
Ploidias , Isolamento Reprodutivo , Tabaco/genética , Cromossomos de Plantas/genética , Cruzamentos Genéticos , DNA Intergênico/genética , Citometria de Fluxo , Flores/anatomia & histologia , Germinação/genética , Filogenia , Folhas de Planta/anatomia & histologia , Análise de Sequência de DNA , Tabaco/anatomia & histologia , Tabaco/fisiologia
8.
Parasitol Int ; 71: 167-176, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31015033

RESUMO

A detailed morphological description and ribosomal DNA (rDNA) sequence molecular data for Aspidogaster ijimai from Japan are provided. Morphological analysis, including a description of the cirrus-sac, indicate the conspecificity of Japanese and continental East Asian A. ijimai specimens. Analysis of ITS1-5.8S-ITS2 rDNA sequences of Japanese, Chinese and Russian specimens confirmed the morphological results. Phylogenetic analysis using ITS rDNA sequences confirmed that A. ijimai is a sister species for Aspidogaster chongqingensis. Median-joining network analysis showed an initial molecular differentiation step of Russian specimens from group of Japanese-Chinese samples. Our 28S rDNA results based on maximum likelihood (ML) and Bayesian (BI) phylogenetic analyses indicated well-supported monophyly of the Aspidogaster conchicola + A. ijimai group, a finding that indicates that these species are congeneric. At the same time, our data demonstrated that the genus Lobatostoma is paraphyletic and the family Aspidogastridae is polyphyletic, results that confirm previous studies.


Assuntos
Bivalves/parasitologia , Carpas/parasitologia , Filogenia , Trematódeos/classificação , Animais , Teorema de Bayes , DNA de Helmintos/genética , DNA Intergênico/genética , DNA Ribossômico/genética , Extremo Oriente , Água Doce/parasitologia , Funções Verossimilhança , RNA Ribossômico 28S/genética
9.
Fungal Biol ; 123(4): 290-306, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30928038

RESUMO

Complex of microfungi colonizing mineral building materials, i.e. limestone and plaster, in interiors of cultural heritage was characterized. Wide-scale investigation was carried out with fourteen objects studied. We have revealed a specific culturable community. We have analyzed role of obtained microfungi in biodeterioraton process on the basis of our tests (pH and water activity preferences, ability to solubilize CaCO3) and literature data (substrate preferences and enzyme activities). The species most actively developing in mineral materials in indoor environments were Acremonium charticola, Acremonium furcatum, Lecanicillium sp., Parengyodontium album, Purpureocillium lilacinum and Sarocladium kiliense. Considering this fact and their ability to develop successfully at extremely wide range of pH values from slightly acidic to alkaline ones and their high enzymatic activities we conclude that the listed species are of high interest in seeking the cause of biodeterioration. These species can actively develop in materials penetrating for years deep into the substrates and causing their deterioration in conditions of considerably heightened moisture content. In this group, A. charticola and Lecanicillium sp. were able to solubilize CaCO3.


Assuntos
Materiais de Construção/microbiologia , Fungos/classificação , Fungos/isolamento & purificação , DNA Fúngico/química , DNA Fúngico/genética , DNA Intergênico/química , DNA Intergênico/genética , Enzimas/análise , Fungos/genética , Fungos/fisiologia , Concentração de Íons de Hidrogênio , Técnicas Microbiológicas , Técnicas de Diagnóstico Molecular , Filogenia , Análise de Sequência de DNA , Água/química
10.
Methods Mol Biol ; 1933: 187-194, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30945185

RESUMO

Long intergenic noncoding RNAs (lincRNAs), which possess diverse features such as remodeling chromatin and genome architecture, RNA stabilization, and genome architecture, are important regulatory factors in plant genomes. They serve to fine-tune the expression of neighboring genes. Here, we describe a procedure of discovery, identification, and functional characterization of plant lincRNAs after virus infection. From high-throughput RNA-Seq transcriptome analysis, the noncoding RNA transcripts with significant fold changes (upregulation or downregulation) will be discovered and identified. The lincRNA of interest will be further confirmed and validated using rapid amplification of cDNA ends (RACE). In addition, functional characterization of the lincRNA will be followed up through overexpression and knockdown strategies.


Assuntos
Arabidopsis/genética , Arabidopsis/virologia , DNA Intergênico/genética , Regulação da Expressão Gênica de Plantas , Genoma de Planta , RNA Longo não Codificante/genética , RNA de Plantas/genética , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de RNA , Transcriptoma
11.
Methods Mol Biol ; 1933: 197-205, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30945186

RESUMO

Long noncoding RNAs (lncRNAs) play important roles in regulating various biological processes including growth and stress responses in plants. RNA-seq data sets provide a good resource to exploring the noncoding transcriptome and studying their comprehensive interactions with the coding transcriptome. Here, we describe computational procedures for studying plant lncRNAs including long intergenic noncoding RNAs (lincRNAs) and long noncoding natural antisense transcripts (lncNATs). Bioinformatics tools for transcriptome assembly, lncRNA identification, and functional interpretations are included. Finally, we also introduce PLncDB, a user-friendly database that provides comprehensive information of plant lncRNAs for researchers to compare their own data sets to those in public database.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Biologia Computacional/métodos , Regulação da Expressão Gênica de Plantas , Sequenciamento de Nucleotídeos em Larga Escala/métodos , RNA Longo não Codificante/genética , RNA de Plantas/genética , DNA Intergênico/genética , RNA Antissenso/genética , Transcriptoma
12.
Methods Mol Biol ; 1933: 207-221, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30945187

RESUMO

Long intergenic noncoding RNA (lincRNA) plays important biological functions in plants. Identification and annotation of lincRNA in plants largely rely on RNA sequencing followed by computational analysis. In this protocol, we describe a multistep computational pipeline for lincRNA identification using RNA-sequencing data. This pipeline can also construct co-expression network that is made of both lincRNA and mRNA genes. The co-expression network generated by this pipeline can be used to provide putative annotation of lincRNAs that have no known biological functions.


Assuntos
Arabidopsis/genética , DNA Intergênico/genética , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Sequenciamento de Nucleotídeos em Larga Escala/métodos , RNA Longo não Codificante/genética , RNA de Plantas/genética , Biologia Computacional/métodos , Transcriptoma
13.
Genome ; 62(5): 295-304, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30998112

RESUMO

Whether ribosomal genes can be used as DNA barcodes for molecular identification of Demodex (Acariformes: Demodicidae) is unclear. To examine this, Demodex folliculorum, D. brevis, D. canis, and D. caprae were collected for DNA extraction, rDNA fragments amplification, sequencing, and analysis. The V2 and V4 regions of SSU rDNA; D5, D6, and D8 regions of LSU rDNA; and ITS region were obtained from the four morphospecies. BLAST analysis showed that the obtained sequences matched those of Demodex or Aplonobia (Acariformes: Tetranychidae) in Raphignathae. Phylogenetic trees derived from V2, V4, D5, D6, and D8 regions, but not from ITS region, showed that the four species of Demodex clustered independently. Sequence divergence analysis further demonstrated that D5, D6, and D8 regions had obvious barcoding gap between intraspecific and interspecific divergences, with the gap of D5 (16.91%) larger than that of D6 (11.82%) and D8 (4.66%). The V2 and V4 regions did not have a barcoding gap, as the intraspecific and interspecific divergences partially overlapped. For the ITS region, intraspecific and interspecific divergences completely overlapped. These results suggest that the D5, D6, and D8 regions of LSU rDNA, especially D5, are suitable DNA barcodes for Demodex.


Assuntos
Código de Barras de DNA Taxonômico , Ácaros/classificação , Animais , DNA Intergênico/genética , DNA Ribossômico/genética , Ácaros/genética , Filogenia
14.
mSphere ; 4(2)2019 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-30944210

RESUMO

Elizabethkingia anophelis is an emerging global multidrug-resistant opportunistic pathogen. We assessed the diversity among 13 complete genomes and 23 draft genomes of E. anophelis strains derived from various environmental settings and human infections from different geographic regions around the world from 1950s to the present. Putative integrative and conjugative elements (ICEs) were identified in 31/36 (86.1%) strains in the study. A total of 52 putative ICEs (including eight degenerated elements lacking integrases) were identified and categorized into three types based on the architecture of the conjugation module and the phylogeny of the relaxase, coupling protein, TraG, and TraJ protein sequences. The type II and III ICEs were found to integrate adjacent to tRNA genes, while type I ICEs integrate into intergenic regions or into a gene. The ICEs carry various cargo genes, including transcription regulator genes and genes conferring antibiotic resistance. The adaptive immune CRISPR-Cas system was found in nine strains, including five strains in which CRISPR-Cas machinery and ICEs coexist at different locations on the same chromosome. One ICE-derived spacer was present in the CRISPR locus in one strain. ICE distribution in the strains showed no geographic or temporal patterns. The ICEs in E. anophelis differ in architecture and sequence from CTnDOT, a well-studied ICE prevalent in Bacteroides spp. The categorization of ICEs will facilitate further investigations of the impact of ICE on virulence, genome epidemiology, and adaptive genomics of E. anophelis IMPORTANCE Elizabethkingia anophelis is an opportunistic human pathogen, and the genetic diversity between strains from around the world becomes apparent as more genomes are sequenced. Genome comparison identified three types of putative ICEs in 31 of 36 strains. The diversity of ICEs suggests that they had different origins. One of the ICEs was discovered previously from a large E. anophelis outbreak in Wisconsin in the United States; this ICE has integrated into the mutY gene of the outbreak strain, creating a mutator phenotype. Similar to ICEs found in many bacterial species, ICEs in E. anophelis carry various cargo genes that enable recipients to resist antibiotics and adapt to various ecological niches. The adaptive immune CRISPR-Cas system is present in nine of 36 strains. An ICE-derived spacer was found in the CRISPR locus in a strain that has no ICE, suggesting a past encounter and effective defense against ICE.


Assuntos
Conjugação Genética/genética , Flavobacteriaceae/genética , Flavobacteriaceae/isolamento & purificação , Variação Genética , Genoma Bacteriano , Imunidade Adaptativa , Animais , Proteínas da Membrana Bacteriana Externa/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Culicidae/microbiologia , DNA Intergênico/genética , Flavobacteriaceae/patogenicidade , Infecções por Flavobacteriaceae/microbiologia , Genômica , Saúde Global , Humanos , Filogenia , Virulência/genética
15.
Parasitol Int ; 71: 80-86, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30974206

RESUMO

To assess the prevalence and molecular characteristics of Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi in grazing adult sheep from Xinjiang Uygur Autonomous Region, China, 318 fecal samples were collected and screened for the presence of these parasites by polymerase chain reaction. The overall infection rate for the three pathogens was 13.5% (43/318), with observed individual infection rates of 0.9% (3/318), 7.5% (24/318), and 6.3% (20/318) for Cryptosporidium spp., G. duodenalis, and E. bieneusi, respectively. Three Cryptosporidium species were identified amongst the samples, including C. xiaoi (n = 1), C. ubiquitum (n = 1), and C. parvum (n = 1), with gp60-based subtyping analysis identifying C. parvum as subtype IIdA15G1 and C. ubiquitum as subtype XIIa. Eight E. bieneusi genotypes were identified based on internal transcribed spacer region sequencing, including six known (BEB6, CHG1, CHG3, CHS3, CHS8, and COS-I) and two novel (designated XJS1 and XJS2) genotypes. All G. duodenalis-positive samples were identified as assemblage E based on small subunit rRNA (n = 24) and gdh (n = 10) gene sequence analysis. These data support the occurrence of host adaptation by Cryptosporidium spp., G. duodenalis, and E. bieneusi in sheep, and the zoonotic risk may posed by these parasites in Xinjiang, China.


Assuntos
Cryptosporidium/genética , Enterocytozoon/genética , Giardia lamblia/genética , Ovinos/parasitologia , Animais , China/epidemiologia , Criptosporidiose/epidemiologia , Cryptosporidium/classificação , DNA Intergênico/genética , Enterocytozoon/classificação , Fezes/parasitologia , Genótipo , Giardia lamblia/classificação , Giardíase/epidemiologia , Giardíase/veterinária , Microsporidiose/epidemiologia , Microsporidiose/veterinária , Prevalência , RNA Ribossômico/genética , Análise de Sequência de DNA , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/parasitologia
16.
Parasitol Int ; 71: 59-72, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30844482

RESUMO

Pigeons members of the order Columbiformes are a cosmopolitan group of birds with abundant and large populations associated with human activities. Therefore, the current study was conducted to determine the parasitic infections within the domestic pigeon Columba livia domestica. Eighteen pigeons were examined for the presence of gastrointestinal helminths, of which 77.78% were infected with a cyclophyllidean cestoda parasites. The morphology of this parasite based on light and scanning electron microscopic studies, revealed the presence of gravid worms, 2.00-4.52 cm long and 0.23-0.59 mm wide; a scolex had four suckers equipped by 5-6 rows of minute hooks and retractable rostellum with 230-250 hooks; genital pores unilateral; oval testes with 27-37 in number; bilobed ovary; post-ovarian vitelline gland; and 24-28 egg capsules present in uterus with 5-6 spherical eggs in each capsule. Molecular analysis based on sequences of ITS2 and ND1 gene regions was performed to confirm the taxonomy of this parasite based on its morphology. This revealed close identity of up to 92.0% and 72.0% for ITS2 and ND1 gene regions, respectively, with other cestoda species obtained from GenBank. Phylogenetic analysis supported the placement of this cycllophylid species within Davaineidae with close relationships to the previously described species of R. chiltoni, R. dromaius, and R. beveridgei based on the ITS2 gene region and R. coreensis and R. sonini based on the ND1 gene regions. Heavy metals accumulation in the recovered parasite and its host showed significantly higher concentrations in the parasite compared to its host tissues. Generally, concentrations of metals exceeded the permissible limits recommended by the US Environmental Protection Agency. Therefore, pigeon cestodes can be regarded as useful bio-indicators when evaluating the environmental pollution of terrestrial ecosystems by heavy metals.


Assuntos
Cestoides/anatomia & histologia , Cestoides/genética , Infecções por Cestoides/veterinária , Columbidae/parasitologia , Poluição Ambiental/análise , Metais Pesados/análise , Animais , DNA de Helmintos/genética , DNA Intergênico/genética , Biomarcadores Ambientais , Feminino , Trato Gastrointestinal/parasitologia , Filogenia
17.
Parasitol Int ; 71: 180-185, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30926538

RESUMO

Trematodes of the genus Plesiochorus were recovered from the urinary bladder of a stranded female adult loggerhead sea turtle, Caretta caretta, on a beach in Rio de Janeiro State, Brazil. Morphological analysis of the specimens revealed characteristics resembling the sub-species Plesiochorus cymbiformis elongatus rather than the recently synonymised Plesiochorus cymbiformis. Molecular phylogenetic analysis of the ITS2 region also showed that P. c. elongatus was distinct from P. cymbiformis and related taxa. Further analysis of the ITS2 revealed substantial differentiation between P. cymbiformis from the USA and Brazil and the newly sequenced P. c. elongatus from Brazil, while a previously unspecified Plesiochorus sp. from the USA closely related to the novel Brazilian P. c. elongatus was reconciled as a USA isolate of P. c. elongatus. Based on both the morphological and molecular data it is suggested that P. c. elongatus should be referred to as Plesiochorus elongatus and be considered as the second species in the genus.


Assuntos
Filogenia , Trematódeos/classificação , Tartarugas/parasitologia , Bexiga Urinária/parasitologia , Animais , Brasil , DNA de Helmintos/genética , DNA Intergênico/genética , Feminino
18.
Parasitol Res ; 118(5): 1393-1402, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30863896

RESUMO

Anisakis and Contracaecum species are fish borne zoonotic nematodes. In our previous studies, other larval anisakid and raphidascarid nematodes, Anisakis and Hysterothylacium species, were genetically identified in marine fish from Turkish waters. However, there is no information on molecular identification of larval Contracaecum species in marine fish from Turkey. Therefore, the aim of this study was only to investigate the presence and molecular identification of Contracaecum species in commonly commercialized marine fish from Turkish waters. A total of 475 marine fish, which belong to 21 different species, were sampled from the Aegean (FAO 37.3.1), Mediterranean (FAO 37.3.2), and Black Sea (FAO 37.4.2). The prevalence of Contracaecum L3 larvae in the Aegean Sea was identified as 10% in Mugil cephalus. All Contracaecum L3 larvae were molecularly characterized with RFLP targeting the ITS region and rrnS gene. Moreover, all larvae were analyzed by sequencing of ITS region, rrnS and cox2 gene. All Contracaecum larvae were identified as C. overstreeti based on the cox2 sequence analysis. This is the first report of C. overstreeti larvae in M. cephalus as paratenic and intermediate hosts. Furthermore, the analysis reveals novel information on ITS region. Additionally, the rrnS gene of C. overstreeti was also achieved and deposited in Genbank for the first time. The PCR-RFLP patterns of the ITS region and rrnS gene from C. overstreeti were presented in the present study. Consequently, the presence of C. overstreeti larvae in M. cephalus from the Aegean Sea may also potentially capable of inducing allergic sensitization in humans.


Assuntos
Anisaquíase/veterinária , Anisakis/classificação , Anisakis/isolamento & purificação , Ascaridoidea/classificação , Ascaridoidea/isolamento & purificação , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/parasitologia , Smegmamorpha/parasitologia , Animais , Anisaquíase/parasitologia , Anisakis/genética , Ascaridoidea/genética , Mar Negro , DNA Intergênico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Peixes/parasitologia , Larva/genética , Mar Mediterrâneo , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Turquia
19.
Parasitol Res ; 118(5): 1465-1472, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30911911

RESUMO

Gnathostomiasis, an emerging food-borne parasitic zoonosis in Asia, is mainly caused by Gnathostoma spinigerum (Nematoda: Gnathostomatidae). Consumption of raw meat or freshwater fishes in endemic areas is the major risk factor. Throughout Southeast Asia, including Thailand, Lao PDR, Cambodia, and Myanmar, freshwater fish are often consumed raw or undercooked. The risk of this practice for gnathostomiasis infection in Lao PDR, Cambodia, and Myanmar has never been evaluated. Here, we identified larvae of Gnathostoma species contaminating freshwater fishes sold at local markets in these three countries. Public health authorities should advise people living in, or travelling to, these areas to avoid eating raw or undercooked freshwater fishes. Identification of larvae was done using molecular methods: DNA was sequenced from Gnathostoma advanced third-stage larvae recovered from snakehead fishes (Channa striata) and freshwater swamp eels (Monopterus albus). Phylogenetic analysis of a portion of the mitochondrial cytochrome c oxidase subunit I gene showed that the G. spinigerum sequences recovered from southern Lao PDR, Cambodia, and Myanmar samples had high similarity to those of G. spinigerum from China. Sequences of the nuclear ribosomal DNA internal transcribed spacer 2 region closely resembled sequences of G. spinigerum from Thailand, Indonesia, the USA, and central Lao PDR. This is the first molecular evidence of G. spinigerum from freshwater fishes in southern Lao PDR, Cambodia, and Myanmar.


Assuntos
Anguilla/parasitologia , Peixes/parasitologia , Gnathostoma/classificação , Gnatostomíase/veterinária , Smegmamorpha/parasitologia , Animais , Camboja , DNA Intergênico/genética , DNA de Protozoário/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Doenças Transmitidas por Alimentos/parasitologia , Água Doce , Variação Genética , Gnathostoma/genética , Gnathostoma/isolamento & purificação , Gnatostomíase/parasitologia , Indonésia , Laos , Larva , Mianmar , Filogenia , Zoonoses/parasitologia
20.
Parasitol Res ; 118(5): 1445-1456, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30919063

RESUMO

Digenean parasites feature a series of stages with a distinct appearance, reproduction mode, and lifestyle that together constitute their well-known, complex life cycle. Species descriptions of Digenea have always been based on one of these stages-the marita, or sexually reproducing adult in the final host. However, in some cases, data on the life cycle are essential for the differential diagnosis of closely related species. Here, we present the case of Notocotylus atlanticus, where different stages of its life cycle were discovered for the first time since the species description, and across the Atlantic. We used a material from a naturally infected intertidal marine snail, Ecrobia ventrosa, and several waterfowl species and also carried out infection experiments. For morphological studies, we employed light microscopy, SEM, and CLSM; molecular data obtained include sequences of ITS1 and 28S rRNA gene. We demonstrate that N. atlanticus adult worm morphology is barely sufficient to distinguish it from several other species. Cercariae morphology and identity of the first intermediate hosts provide crucial additional information. According to our preliminary phylogenetic reconstructions, two notocotylid lineages are associated with two major gastropod lineages-the Caenogastropoda and the Heterobranchia. The traditional character to identify notocotylid genera (structure of ventral organs) fails to explain the phylogeny and thus requires reassessment. Further reliable morphological, life cycle and molecular data on other species are likely to reveal more patterns in notocotylid systematics, host specificity, and evolution.


Assuntos
Estágios do Ciclo de Vida/fisiologia , Caramujos/parasitologia , Trematódeos/classificação , Trematódeos/crescimento & desenvolvimento , Animais , Cercárias/genética , DNA Intergênico/genética , Especificidade de Hospedeiro , Filogenia , RNA Ribossômico 28S/genética , Trematódeos/genética
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