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1.
Exp Parasitol ; 263-264: 108806, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39009178

RESUMEN

Dirofilaria immitis is a filarial parasitic nematode of veterinary significance. With the emergence of drug-resistant isolates in the USA, it is imperative to determine the likelihood of resistance occurring in other regions of the world. One approach is to conduct population genetic studies across an extensive geographical range, and to sequence the genomes of individual worms to understand genome-wide genetic variation associated with resistance. The immature life stages of D. immitis found in the host blood are more accessible and less invasive to sample compared to extracting adult stages from the host heart. To assess the use of immature life stages for population genetic analyses, we have performed whole genome amplification and whole-genome sequencing on nine (n = 9) individual D. immitis microfilaria samples isolated from dog blood. On average, less than 1% of mapped reads aligned to each D. immitis genome (nuclear, mitochondrial, and Wolbachia endosymbiont). For the dog genome, an average of over 99% of mapped reads aligned to the nuclear genome and less than 1% aligned to the mitochondrial genome. The average coverage for all D. immitis genomes and the dog nuclear genome was less than 1, while the dog mitochondrial genome had an average coverage of 2.87. The overwhelming proportion of sequencing reads mapping to the dog host genome can be attributed to residual dog blood cells in the microfilariae samples. These results demonstrate the challenges of conducting genome-wide studies on individual immature parasite life stages, particularly in the presence of extraneous host DNA.


Asunto(s)
ADN de Helmintos , Dirofilaria immitis , Dirofilariasis , Enfermedades de los Perros , Genoma de los Helmintos , Microfilarias , Secuenciación Completa del Genoma , Animales , Dirofilaria immitis/genética , Dirofilaria immitis/aislamiento & purificación , Perros , Enfermedades de los Perros/parasitología , Dirofilariasis/parasitología , Microfilarias/genética , Microfilarias/aislamiento & purificación , ADN de Helmintos/aislamiento & purificación , ADN de Helmintos/química , Femenino , Masculino
2.
BMC Biotechnol ; 21(1): 35, 2021 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-34001079

RESUMEN

BACKGROUND: The purpose of this study was to develop a reliable DNA extraction protocol to use on individual Teladorsagia circumcincta nematode specimens to produce high quality DNA for genome sequencing and phylogenetic analysis. Pooled samples have been critical in providing the groundwork for T. circumcincta genome construction, but there is currently no standard method for extracting high-quality DNA from individual nematodes. 11 extraction kits were compared based on DNA quality, yield, and processing time. RESULTS: 11 extraction protocols were compared, and the concentration and purity of the extracted DNA was quantified. Median DNA concentration among all methods measured on NanoDrop 2000™ ranged between 0.45-11.5 ng/µL, and on Qubit™ ranged between undetectable - 0.962 ng/µL. Median A260/280 ranged between 0.505-3.925, and median A260/230 ranged - 0.005 - 1.545. Larval exsheathment to remove the nematode cuticle negatively impacted DNA concentration and purity. CONCLUSIONS: A Schistosoma sp. DNA extraction method was determined as most suitable for individual T. circumcincta nematode specimens due to its resulting DNA concentration, purity, and relatively fast processing time.


Asunto(s)
ADN de Helmintos/genética , ADN de Helmintos/aislamiento & purificación , Técnicas Genéticas , Enfermedades de las Ovejas/parasitología , Infecciones por Strongylida/veterinaria , Estrongílidos/genética , Animales , Heces , Filogenia , Análisis de Secuencia de ADN , Ovinos , Estrongílidos/clasificación , Estrongílidos/aislamiento & purificación , Infecciones por Strongylida/parasitología
3.
Parasitology ; 148(8): 913-933, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33775267

RESUMEN

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.


Asunto(s)
Cysticercus/genética , Enfermedades de las Ovejas/parasitología , Teniasis/parasitología , Animales , Análisis por Conglomerados , Cysticercus/clasificación , ADN de Helmintos/química , ADN de Helmintos/aislamiento & purificación , Egipto/epidemiología , Femenino , Salud Global , Haplotipos , Masculino , Filogenia , Polimorfismo Genético , ARN Ribosómico/genética , Ríos , Alineación de Secuencia , Ovinos , Enfermedades de las Ovejas/epidemiología , Taenia/clasificación , Taenia/genética , Teniasis/epidemiología
4.
Parasitology ; 148(8): 1003-1018, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33843503

RESUMEN

The fauna of the Apennine Peninsula is, in comparison to other southern European peninsulas, relatively species-poor regarding the number of endemic cyprinoid species. Nonetheless, the recent introduction of non-native species has significantly increased the total number of freshwater species in this region. Such invasive species may represent a threat to the native fauna, associated among other things with the introduction of non-native parasites with their original hosts.In the present study, we investigated endemic cyprinoid species for the presence of helminth parasites. A total of 36 ectoparasitic monogenean species and five endoparasitic helminth species were collected from ten cyprinoid species in five localities in northern Italy. Out of 20 Dactylogyrus species (gill monogeneans specific to cyprinoids), four were identified as new to science and herein described: Dactylogyrus opertus n. sp. and Dactylogyrus sagittarius n. sp. from Telestes muticellus, Dactylogyrus conchatus n. sp. from T. muticellus and Protochondrostoma genei, and Dactylogyrus globulatus n. sp. from Chondrostoma soetta. All new Dactylogyrus species appear to be endemic to the Apennine Peninsula; however, they share a common evolutionary history with the endemic Dactylogyrus parasitizing cyprinoids of the Balkans. This common origin of cyprinoid-specific parasites supports a historical connection between these two (currently separated) geographical regions.


Asunto(s)
Infestaciones Ectoparasitarias/veterinaria , Enfermedades de los Peces/parasitología , Helmintiasis Animal/epidemiología , Helmintiasis Animal/parasitología , Peces Killi/parasitología , Animales , ADN de Helmintos/química , ADN de Helmintos/aislamiento & purificación , Infestaciones Ectoparasitarias/epidemiología , Infestaciones Ectoparasitarias/parasitología , Enfermedades de los Peces/epidemiología , Variación Genética , Branquias/parasitología , Helmintos/anatomía & histología , Helmintos/clasificación , Helmintos/genética , Italia/epidemiología , Filogenia , Ríos , Trematodos/clasificación , Trematodos/genética , Trematodos/aislamiento & purificación
5.
Exp Parasitol ; 224: 108098, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33713659

RESUMEN

Molecular diagnostics are powerful tools for disease detection but are typically confined to the laboratory environment due to the cumbersome methods required to extract nucleic acids from biological samples. Accurate diagnosis is essential for early detection of parasitic worm infections and for monitoring control programs, particularly during new transmission outbreaks to limit infection spread. We optimized the recently developed DNA dipstick technology to purify Schistosoma japonicum DNA from different life stages in <60 s. We successfully detected DNA from adult worms, eggs and infected snails. The speed and simplicity of this method enables the point-of-care detection of S. japonicum.


Asunto(s)
ADN de Helmintos/aislamiento & purificación , Schistosoma japonicum/aislamiento & purificación , Esquistosomiasis Japónica/diagnóstico , Animales , Hígado/parasitología , Ratones , Técnicas de Diagnóstico Molecular , Técnicas de Amplificación de Ácido Nucleico , Pruebas en el Punto de Atención , Reacción en Cadena en Tiempo Real de la Polimerasa , Schistosoma japonicum/genética , Esquistosomiasis Japónica/prevención & control , Caracoles/parasitología
6.
Exp Parasitol ; 230: 108157, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34543651

RESUMEN

Strongyloides venezuelensis has been used in different experimental studies, such as those aimed at the evaluation of diagnostic techniques for human strongyloidiasis, mainly the molecular diagnosis. In this study, three regions (genus, 18S and 28S targets) of Strongyloides ribosomal DNA were evaluated for the molecular diagnosis of experimental strongyloidiasis. Rats were infected subcutaneously with 400 or 4000 S. venezuelensis infective larvae (400iL3 and 4000iL3), and kept for 35 days. Fecal samples were collected daily to count eggs per gram of feces (EPG) and to perform the polymerase chain reaction (PCR). Egg count started on the 5th day post-infection (pi) and ended on days 33 and 34 pi, in 400iL3 and 4000iL3 groups, respectively. Based in EPG, fecal samples were selected from days 2, 5, 8, 11, 15, 23 and 35 pi for DNA extraction; PCR (genus, 18S and 28S); and sequencing. The PCR-28S products showed higher values of identity (95-100%) in the database with the Strongyloides sequences. Therefore, it is possible to reinforce the application of PCR-28S in the diagnosis of experimental and human strongyloidiasis.


Asunto(s)
ADN Ribosómico/genética , ARN Ribosómico 18S/genética , ARN Ribosómico 28S/genética , Strongyloides/genética , Estrongiloidiasis/diagnóstico , Animales , ADN de Helmintos/genética , ADN de Helmintos/aislamiento & purificación , ADN Ribosómico/aislamiento & purificación , Heces/parasitología , Humanos , Larva/genética , Masculino , Recuento de Huevos de Parásitos , Reacción en Cadena de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa/normas , Ratas , Ratas Wistar , Sensibilidad y Especificidad , Strongyloides/patogenicidad
7.
Parasitol Res ; 120(2): 731-737, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33442815

RESUMEN

Alveolar echinococcosis (AE) is a zoonosis caused by Echinococcus multilocularis, a heteroxenous parasite belonging to Cestoda class. AE is currently considered an important public health issue, but epidemiological and notably molecular data from several endemic countries, including Pakistan, are sparse. Here we report the first detection of Echinococcus multilocularis in wildlife from Pakistan after real-time PCR and sequencing confirmation in the faecal samples of three foxes from northern Kaghan and Siran regions. The occurrence is estimated at 4.4% (95% CI 0.9-12.4). In order to go further in the epidemiological investigations on E. multilocularis and due to the potential presence of other Echinococcus species, we suggest the need for further epidemiological surveys targeting E. multilocularis and E. granulosus sensu lato isolates from humans and intermediate hosts as well as definitive hosts from wildlife in Pakistan.


Asunto(s)
ADN de Helmintos/aislamiento & purificación , Echinococcus multilocularis/aislamiento & purificación , Zorros/parasitología , Animales , Animales Salvajes/parasitología , ADN de Helmintos/genética , Perros , Echinococcus multilocularis/genética , Heces/parasitología , Pakistán , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Análisis de Secuencia de ADN
8.
Parasitol Res ; 120(7): 2357-2362, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34156539

RESUMEN

Nectonema, the only horsehair worm (Nematomorpha) genus found in marine environments, was previously known to be parasitic only in decapod crustaceans. We report Nectonema sp. as the first record of a marine nematomorph parasitic in isopod crustaceans. This is also the third record of marine nematomorphs from the North Pacific. Six infected isopods (Natatolana japonensis) collected from 1425 m of depth in the Sea of Japan each contained one to seven (mean 2.33) nematomorphs in the body cavity in the pereon. There was no correlation between the host body length and number of parasites. For Nectonema sp., we describe and illustrate morphological features of the parasitic juvenile stage and present nucleotide sequences for the cytochrome c oxidase subunit I gene (COI or cox1; 451 nt), 18S rRNA gene (1777 nt), and region spanning the internal transcribed spacer 1 (ITS1) and the 28S rRNA gene including the 5.8S rRNA gene and ITS2 (1218 nt in total). In an 18S maximum-likelihood tree that included 24 nematomorph species, Nectonema sp. grouped with N. agile from the northwestern Atlantic; the 18S gene from these two taxa was divergent by 11.8% K2P distance, suggesting that they are different species. Nectonema species may have a broader range of host groups than previously suspected, but may have been previously misidentified as nematode parasites.


Asunto(s)
Helmintos/patogenicidad , Isópodos/parasitología , Animales , ADN de Helmintos/química , ADN de Helmintos/aislamiento & purificación , Femenino , Helmintos/clasificación , Helmintos/genética , Helmintos/aislamiento & purificación , Japón , Masculino , Filogenia , Reacción en Cadena de la Polimerasa , ARN Ribosómico 18S/química , ARN Ribosómico 18S/genética , ARN Ribosómico 28S/genética , ARN Ribosómico 5.8S/genética
9.
Mol Biol Rep ; 47(1): 703-709, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31713008

RESUMEN

Effective isolation of high-quality genomic DNA is one of the essential steps in molecular biology, biochemistry, and genetic studies. Here we describe a simplified procedure based on repeated freeze-thawing cycles to isolate genomic DNA from different organisms of microbes (Burkholderia pyrrocinia JK-SH007, Bacillus pumilus HRl0, Botrytis cinerea) and nematodes (Bursaphelenchus xylophilus). The DNA extraction buffer includes 10% of CTAB; 4% of NaCl (W/V); 20 mM of ethylenediamine tetraacetic acid; 100 mM of Tris-HCl, pH 8.0 and 1% of polyvinylpyrrolidone. The released DNA was purified from the mixture using a phenol/chloroform mixture and precipitated in 70% ethanol to remove proteins, carbohydrates, phenols, RNA, etc. Our method is a reproducible, simple, and rapid technique for routine DNA extractions from various microorganisms and nematodes. Furthermore, the low cost of this method could be an economic benefit to large-scale studies.


Asunto(s)
Fraccionamiento Químico/métodos , ADN Bacteriano/aislamiento & purificación , Técnicas Microbiológicas/métodos , Animales , Bacterias/química , Bacterias/genética , Tampones (Química) , ADN Bacteriano/análisis , ADN de Helmintos/análisis , ADN de Helmintos/aislamiento & purificación , Congelación , Técnicas Genéticas , Nematodos/química , Nematodos/genética
10.
BMC Vet Res ; 16(1): 16, 2020 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-31937305

RESUMEN

BACKGROUND: Parasites of the family Spirorchiidae cause disease and mortality in marine and freshwater turtles; two species, Hapalotrema mistroides and Neospirorchis sp., are reported in the resident population of loggerhead turtles of the Mediterranean Sea, with the first being the most widespread. In vivo diagnosis of spirorchidiasis can represent a challenge in guaranteeing prompt control and treatment of the disease and is currently limited to copromicroscopy. The aim of this study was the development of a real time PCR assay with TaqMan probe for the detection of H. mistroides infection in the blood of live loggerhead turtles, Caretta caretta, hospitalized in rehabilitation centres. Its potential use for in vivo diagnosis is explored. RESULTS: The developed real time PCR successfully detected H. mistroides DNA from both positive controls and experimental blood samples of live loggerhead sea turtles, showing good specificity, sensitivity and good reaction efficiency. Two out of three turtles which had demonstrated positivity at copromicroscopy also tested positive to this blood assay; DNA of H. mistroides was detected within the blood of one sea turtle, which tested negative for copromicroscopy. CONCLUSIONS: This study describes a specific and rapid molecular assay to detect H. mistroides infection from live sea turtles and highlights for the first time the presence of DNA of this species in turtle blood samples. Since this assay is able to detect low amounts of the parasitic free DNA in blood samples, its application could be helpful for in vivo diagnosis of H. mistroides infection as well as for epidemiological purposes.


Asunto(s)
Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Infecciones por Trematodos/veterinaria , Tortugas/parasitología , Animales , ADN de Helmintos/aislamiento & purificación , Heces/parasitología , Mar Mediterráneo , Proyectos Piloto , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Sensibilidad y Especificidad , Trematodos/genética , Trematodos/aislamiento & purificación , Infecciones por Trematodos/diagnóstico , Tortugas/sangre
11.
Exp Parasitol ; 208: 107800, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31726054

RESUMEN

The aims of this study were an establishment of the domestic rabbit as an intermediate host for cystic echinococcosis (CE) and to evaluate the potency of the crude germinal layer and the protoscoleces antigens to protect against the CE. Firstly; Two groups of white Newzeland rabbits were infected orally either by 5000 active oncospheres or viable protoscoleces separately. After 20 weeks, the slaughtered rabbits showed the presence of hydatid cysts at different internal organs. Molecular detection of the resulted cysts was conducted. Secondly; 27 rabbits were divided into nine groups (n = 3). Groups 1 and 2 were immunized with the crude germinal layer antigen while the groups 3 and 4 were immunized with the crude protoscoleces antigen. Groups 5 and 6 received the adjuvant mineral oil. Groups 7 and 8 were used as positive control. The last 9 group was kept as a negative control. The obtained results showed a significant high protection percentage of 83.4% and high antibody titer was recorded in groups that received the crude germinal layer antigen comparing with the groups that immunized with the crude protoscoleces antigen as their protection percentage was 66.7% with lower IgG response. In conclusion, the domestic rabbits could be used as a laboratory model for CE. Developing of the germinal layer antigen is more immunogenic than the protoscoleces one and could be used as a promising vaccine. Attention should be directed towards the existing rabbit in the environment adjacent to infected dogs as it could be a part of Echinococcus life cycle.


Asunto(s)
Modelos Animales de Enfermedad , Equinococosis/prevención & control , Echinococcus/inmunología , Conejos , Vacunación , Vacunas , Análisis de Varianza , Animales , Antígenos Helmínticos/inmunología , ADN de Helmintos/aislamiento & purificación , Perros , Echinococcus/genética , Ensayo de Inmunoadsorción Enzimática , Inmunoglobulina G/biosíntesis , Riñón/parasitología , Hígado/parasitología , Pulmón/parasitología , Masculino , Epiplón/parasitología , Potencia de la Vacuna
12.
Exp Parasitol ; 217: 107960, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32755552

RESUMEN

Guinea worm Dracunculus medinensis causes debilitating disease in people and is subject to an ongoing global eradication programme. Research and controls are constrained by a lack of diagnostic tools. We developed a specific and sensitive LAMP method for detecting D. medinensis larval DNA in copepod vectors. We were able to detect a single larva in a background of field-collected copepods. This method could form the basis of a "pond-side test" for detecting potential sources of Guinea worm infection in the environment, in copepods, including in the guts of fish as potential transport hosts, enabling research, surveillance and targeting of control measures. The key constraint on the utility of this assay as a field diagnostic, is a lack of knowledge of variation in the temporal and spatial distribution of D. medinensis larvae in copepods in water bodies in the affected areas and how best to sample copepods to obtain a reliable diagnostic sample. These fundamental knowledge gaps could readily be addressed with field collections of samples across areas experiencing a range of worm infection frequencies, coupled with field and laboratory analyses using LAMP and PCR.


Asunto(s)
Copépodos/parasitología , Dracunculus/aislamiento & purificación , Técnicas de Diagnóstico Molecular/normas , Técnicas de Amplificación de Ácido Nucleico/normas , Estanques/parasitología , África , Animales , Secuencia de Bases , Gatos , Copépodos/genética , Cartilla de ADN/química , ADN de Helmintos/aislamiento & purificación , Vectores de Enfermedades , Perros , Dracunculus/genética , Humanos , Papio , Sensibilidad y Especificidad , Factores de Tiempo
13.
Exp Parasitol ; 217: 107957, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32687847

RESUMEN

The ruminant livestock production sector is under threat due to the infections with gastrointestinal nematode parasites and the subsequent development of anthelmintic resistance. One of most common and pathogenic species in small ruminants is Haemonchus contortus. The ability to control the infections with this and other gastrointestinal nematodes relies heavily on the use of anthelmintic drugs. Although resistance to all major classes of anthelmintics has been shown in H. contortus, the precise mechanism of resistance acquisition is only known for benzimidazoles. F200Y (TAC) is a common point mutation in the isotype 1 ß tubulin gene which is associated with an effective increase in the resistance towards benzimidazole drugs. Here, we show the utility of using this mutation as a marker in a droplet digital PCR assay to track how two H. contortus laboratory strains, characterized by different resistance levels, change with respect to this mutation, when subjected to increasing concentrations of thiabendazole. Additionally, we wanted to investigate whether exposure to a discriminating dose of thiabendazole in the egg hatch test resulted in the death of all H. contortus eggs with a susceptible genotype. We found the MHco5 strain to maintain an overall higher frequency of the F200Y mutation (80-100%) over all drug concentrations, whilst a steady, gradual increase from around 30%-60% was observed in the case of the MHco4 strain. This is further supported by the dose-response curves, displaying a much higher tolerance of the MHco5 strain (LD50 = 0.38 µg/ml) in comparison to the MHco4 strain (LD50 = 0.07 µg/ml) to the effects of thiabendazole. All things considered, we show that the F200Y mutation is still a viable and reliable marker for the detection and surveillance of benzimidazole drug resistance in H. contortus in Europe.


Asunto(s)
Antihelmínticos/farmacología , Haemonchus/genética , Tasa de Mutación , Tiabendazol/farmacología , Tubulina (Proteína)/genética , Animales , ADN de Helmintos/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Resistencia a Medicamentos/genética , Frecuencia de los Genes , Marcadores Genéticos , Genotipo , Hemoncosis/parasitología , Hemoncosis/veterinaria , Haemonchus/clasificación , Haemonchus/efectos de los fármacos , Dosificación Letal Mediana , Óvulo/efectos de los fármacos , Fenotipo , Mutación Puntual , Reacción en Cadena de la Polimerasa , Ovinos , Enfermedades de las Ovejas/parasitología
14.
Korean J Parasitol ; 58(6): 689-694, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33412774

RESUMEN

Strongyloidiasis is caused by Strongyloides stercoralis and is one of the most neglected tropical diseases in tropical and subtropical regions. Although several strongyloidiasis cases have been reported in Korea, genetic analysis of Korean isolates is still incomplete. In this study, a parasite was isolated from a 61-year-old man diagnosed with strongyloidiasis during the treatment of lymphoma on his retroperitoneal lymph node. Diffuse symmetric wall thickening from the ascending to descending colon and a nematode-infected intestine was observed following microscopic examination. Genomic DNA was isolated from a patient tissue block, and S. stercoralis was identified by PCR and sequencing (18S rDNA). In order to determine phylogenetic location of a Korean isolate (named KS1), we analyzed cox1 gene (500-bp) and compared it with that from 47 previous S. stercoralis isolates (28 human isolates and 19 canid isolates) from Asian countries. Our results showed that phylogenetic tree could clearly be divided into 5 different groups according to hosts and regions. KS1 was most closely related with the Chinese isolates in terms of genetic distance.


Asunto(s)
Filogenia , Strongyloides stercoralis/genética , Estrongiloidiasis/parasitología , Animales , Asia , Pueblo Asiatico , ADN de Helmintos/genética , ADN de Helmintos/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Análisis de Secuencia de ADN , Strongyloides stercoralis/clasificación , Strongyloides stercoralis/aislamiento & purificación
15.
J Helminthol ; 94: e145, 2020 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-32284088

RESUMEN

Epidemiological studies of Echinococcus multilocularis infections in definitive hosts require a reliable and economic diagnostic method. In this study, the current copro-DNA examination technique was modified by increasing the faecal amounts tested and adding a step to neutralize the faeces before DNA extraction. Reliability of the modified method was evaluated using rectal faecal samples from red foxes and comparing them with intestinal worms detected using the sedimentation and counting technique (SCT) following necropsy. The modified copro-DNA examination method demonstrated 93.9% sensitivity (138/147) on the SCT. Its detectability increased depending on the worm burden, and the sensitivity was 100% in cases harbouring over 1000 worms. From 111 SCT-negative cases, six (5.4%) were copro-DNA-positive, and all were confirmed as E. multilocularis via sequencing analysis. Five of the remaining 105 SCT-negative cases (4.8%) retained polymerase chain reaction (PCR) inhibitors in the extracted solution, suggesting that approximately 5% of the red fox faeces retained these inhibitors after treatment with the present copro-DNA extraction method. Although further evaluation is needed for faeces deposited in the wild, the present copro-DNA examination technique will help monitor the E. multilocularis prevalence in definitive hosts. When used for detailed evaluations of endemicity (e.g. changes in infection pressure or spread in non-endemic areas), the absence of PCR inhibitors should be confirmed, and multiple trials on faecal subsamples are recommended.


Asunto(s)
ADN de Helmintos/aislamiento & purificación , Equinococosis/veterinaria , Heces/parasitología , Zorros/parasitología , Animales , Equinococosis/epidemiología , Echinococcus multilocularis , Heces/química , Prevalencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
16.
J Helminthol ; 94: e163, 2020 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-32539878

RESUMEN

A new species of Creptotrematina Yamaguti, 1954 was collected from characid fishes, Astyanax fasciatus (Cuvier, 1819) and Astyanax lacustris Lucerna & Soares, 2016 from the Batalha River in the State of Sao Paulo, Brazil. The new species most closely resembles Creptotrematina aguirrepequenoi, but differs by the elongated shape of vitelline follicles, the extension of these follicles in the posterior end of body and the fact that they are not confluent. The morphological differences were confirmed through molecular data. Three specimens were sequenced, and molecular analyses were based on the internal transcribed spacers 2 and D1-D3 domains of the 28S ribosomal RNA gene. The obtained topologies showed the new species as a sister taxon of C. aguirrepequenoi, a species originally described from Astyanax mexicanus in Mexico, and later found in Astyanax aeneus in Costa Rica. Isolates of the new species are reciprocally monophyletic, and genetic distance values are similar to those observed in other species pairs within Allocreadiidae. These findings corroborate that the genus Creptotrematina is mostly a parasite of characids, and widely extended across the Americas, with representative species occurring between Argentina and northern Mexico.


Asunto(s)
Characidae/parasitología , Enfermedades de los Peces/parasitología , Trematodos/anatomía & histología , Trematodos/clasificación , Infecciones por Trematodos/veterinaria , Animales , Brasil , ADN de Helmintos/aislamiento & purificación , Femenino , Filogenia , ARN Ribosómico 28S/genética , Ríos , Trematodos/aislamiento & purificación , Infecciones por Trematodos/parasitología
17.
J Helminthol ; 94: e118, 2020 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-31959266

RESUMEN

Glutathione S-transferases (GSTs) are a detoxifying enzyme family that is essential for parasite blood-feeding and survival, and represent potential targets for hookworm vaccine development. Multiple GST-encoding complementary DNAs (cDNAs) have been cloned from Ancylostoma caninum and Necator americanus, but there are no reports about the cloning of this enzyme from Ancylostoma ceylanicum, the animal-derived zoonotic hookworm. To study the molecular nature and tissue localization of GST of A. ceylanicum (Ace-GST), we designed primers based on the GST gene sequence of A. ceylanicum in GenBank, amplified the Ace-GST cDNA by reverse transcription polymerase chain reaction, and analysed its homology and genetic evolution relationship. The amplified product was cloned into the pET-32a vector and transformed into Escherichia coli BL21 (DE3) for expression. To prepare anti-GST polyclonal antibodies, the recombinant protein was purified and used to immunize Kunming mice. The level of immunoglobulin G (IgG) antibody in the serum of immunized mice was detected by indirect enzyme-linked immunosorbent assay, and the Ace-GST localization in adult worm was determined using the immunofluorescence method. The results showed that the full-length cDNA encoding Ace-GST was 468 bp, which had the highest homology with Ac-GST-1 (60.1%) and clustered into one branch (v-class) with Ac-GST-1 and Na-GST-1 in a phylogenetic tree. Mice immunized with recombinant Ace-GST showed specific IgG antibody response. Immunolocalization revealed that natural Ace-GST is mainly located in the epidermis, muscle and intestine of the adult. These results may lay a foundation for further studies on the biological function of Ace-GST.


Asunto(s)
Ancylostoma , Glutatión Transferasa/metabolismo , Ancylostoma/genética , Ancylostoma/inmunología , Ancylostoma/metabolismo , Anquilostomiasis , Animales , Anticuerpos Antihelmínticos , Antígenos Helmínticos/genética , Antígenos Helmínticos/metabolismo , Clonación Molecular , ADN de Helmintos/genética , ADN de Helmintos/aislamiento & purificación , Escherichia coli/genética , Glutatión Transferasa/genética , Inmunohistoquímica , Filogenia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transformación Bacteriana
18.
Anal Chem ; 91(19): 12149-12155, 2019 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-31454479

RESUMEN

Caenorhabditis elegans is used extensively as a medical and toxicological model organism. However, little is known about background levels of oxidatively induced DNA damage in the nematode or how culturing methods affect DNA damage levels. The tough C. elegans cuticle makes it challenging to extract genomic DNA without harsh procedures that can artifactually increase DNA damage. Therefore, a mild extraction protocol based on enzymatic digestion of the C. elegans cuticle with high-salt phase-separation of DNA has been developed and optimized. This method allows for efficient extraction of >50 µg DNA using a minimum of 250000 nematodes grown in liquid culture. The extracted DNA exhibited acceptable RNA levels (<10% contamination), functionality in polymerase chain reaction assays, and reproducible DNA fragmentation. Gas chromatography/tandem mass spectrometry (GC-MS/MS) with isotope-dilution measured lower lesion levels in high-salt extracts than in phenol extracts. Phenolic extraction produced a statistically significant increase in 8-hydroxyguanine, a known artifact, and additional artifactual increases in 2,6-diamino-4-hydroxy-5-formamidopyrimidine, 4,6-diamino-5-formamidopyrimidine, and 8-hydroxyadenine. The high-salt DNA extraction procedure utilizes green solvents and reagents and minimizes artifactual DNA damage, making it more suitable for molecular and toxicological studies in C. elegans. This is, to our knowledge, the first use of GC-MS/MS to measure multiple 8,5'-cyclopurine-2'-deoxynucleosides in a toxicologically important terrestrial organism.


Asunto(s)
Caenorhabditis elegans/genética , Fraccionamiento Químico/métodos , Daño del ADN , ADN de Helmintos/aislamiento & purificación , Adenina/análogos & derivados , Adenina/química , Animales , Artefactos , Femenino , Cromatografía de Gases y Espectrometría de Masas/métodos , Guanina/análogos & derivados , Guanina/química , Humanos , Células MCF-7 , Oxidación-Reducción , Fenoles/química , Pirimidinas/análisis , Pirimidinas/química , Técnica de Dilución de Radioisótopos , Reproducibilidad de los Resultados , Cloruro de Sodio/química , Espectrometría de Masas en Tándem/métodos
19.
J Clin Microbiol ; 57(4)2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30728195

RESUMEN

Strongyloides stercoralis can cause disease that ranges from asymptomatic chronic infection to fatal hyperinfection. Diagnosis from stool can be challenging because the most sensitive conventional tests require live larvae to be effective and there can be low larval output in chronic infection. Nucleic acid amplification tests (NAAT) have been developed to complement existing diagnostic methods. We compared a recently developed loop-mediated isothermal amplification (LAMP) assay with a real-time PCR that has previously been validated with larval microscopy. The limits of detection-quantified using serial dilutions of DNA extracts from single Strongyloides ratti third-stage (L3) larvae spiked into approximately 250 µl of 5 different S. stercoralis-negative stool specimens-were 10-3 (1/5 replicates) and 10-2 (1/5 replicates) dilutions for PCR and LAMP, respectively. PCR was positive for 4/5 replicates at 10-2 LAMP was compared to PCR using extracts from 396 stool specimens collected in Bangladesh and Australia, of which 53 were positive and 343 were negative by PCR. The positive percentage agreement of LAMP was 77.3% (95% score confidence interval [CI], 64.5 to 86.6). The negative percentage agreement was 100% (95% CI, 98.9 to 100). In a preliminary investigation, PCR and LAMP assays were positive using DNA extracted from serum (PCR, 3/16 extracts; LAMP, 2/16 extracts) and bronchoalveolar lavage fluid (PCR and LAMP, 2/2 extracts), demonstrating proof of concept. Compared to PCR, the lower number of positive results using the LAMP assay may have been due to reaction inhibitors and DNA degradation, and strategies to improve the LAMP assay are discussed.


Asunto(s)
Técnicas de Amplificación de Ácido Nucleico/normas , Reacción en Cadena en Tiempo Real de la Polimerasa/normas , Strongyloides stercoralis/aislamiento & purificación , Estrongiloidiasis/diagnóstico , Anciano , Animales , Australia , Bangladesh , Líquido del Lavado Bronquioalveolar/parasitología , Cartilla de ADN/genética , ADN de Helmintos/aislamiento & purificación , Heces/parasitología , Humanos , Larva , Límite de Detección , Masculino , Persona de Mediana Edad , Técnicas de Amplificación de Ácido Nucleico/métodos , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Sensibilidad y Especificidad , Estrongiloidiasis/sangre
20.
Exp Parasitol ; 197: 51-56, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30641035

RESUMEN

The pine wood nematode Bursaphelenchus xylophilus is a disastrous pathogen of pine forests in East Asia and Europe. Despite its decimating effect on pine forests, efficient and environmentally friendly methods available to control the pine wood nematode (PWN) are limited. The most abundant protein in nematode sperm, major sperm proteins (MSPs) have only been discovered in nematodes. In this study, phylogenetic analysis showed that BxMSP10 was highly conserved in the nematode and had a closer phylogenetic relationship with free-living nematodes than with plant-parasitic nematode species. BxMSP10 was specifically expressed in the seminal vesicle of male adults. dsRNA of BxMSP10 significantly decreased reproduction, egg hatching and population maintenance in B. xylophilus. These results indicated that BxMSP10 was a potential candidate for application in the control of B. xylophilus.


Asunto(s)
Proteínas del Helminto/fisiología , Rabdítidos/fisiología , Animales , Botrytis , ADN de Helmintos/aislamiento & purificación , Femenino , Expresión Génica , Hordeum/microbiología , Hordeum/parasitología , Hibridación in Situ , Intrones , Masculino , Filogenia , Pinus/parasitología , Enfermedades de las Plantas/parasitología , Interferencia de ARN , ARN de Helminto/aislamiento & purificación , ARN de Helminto/fisiología , Reproducción/fisiología , Rabdítidos/clasificación , Rabdítidos/genética
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