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1.
Ticks Tick Borne Dis ; 12(3): 101683, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33578257

RESUMO

We performed tick surveys in all regions (Kaetsu, Chuetsu, Joetsu, and Sado) of the Niigata prefecture, Japan. A total of 105 field surveys were done from 2016 to 2018 in 41 sites, from north to south, in the prefecture. All 4806 ticks collected were identified and classified by species, sex, and developmental stage. Twelve species were recorded: Dermacentor taiwanensis, Haemaphysalis flava, Haemaphysalis hystricis, Haemaphysalis japonica, Haemaphysalis longicornis, Haemaphysalis megaspinosa, Ixodes ovatus, Ixodes nipponensis, Ixodes persulcatus, Ixodes monospinosus, Ixodes columnae, and Ixodes turdus. The major tick species in Niigata prefecture were H. flava, H. longicornis, and I. ovatus and they comprised 93.4% of all samples. These three species have one generation per year. Climatic and anthropogenic factors may be involved in the substantial change of the endemic species composition from a previous tick survey (1959) in the Niigata prefecture. These factors include increasing temperatures, introduction of new hosts such as the wild boar, highway construction, and a rural exodus facilitating animal migration and reproduction. Tick hosts suitable for the transmission of Japanese spotted fever, Lyme borreliosis, and SFTS occur in Niigata prefecture. Heightened awareness of these three tick-borne diseases is needed for preparation and disease prevention.

2.
Sci Rep ; 11(1): 2595, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33510192

RESUMO

Japanese spotted fever, a tick-borne disease caused by Rickettsia japonica, was firstly described in southwestern Japan. There was a suspicion of Rickettsia japonica infected ticks reaching the non-endemic Niigata Prefecture after a confirmed case of Japanese spotted fever in July 2014. Therefore, from 2015 to 2017, 38 sites were surveyed and rickettsial pathogens were investigated in ticks from north to south of Niigata Prefecture including Sado island. A total of 3336 ticks were collected and identified revealing ticks of three genera and ten species: Dermacentor taiwanensis, Haemaphysalis flava, Haemaphysalis hystricis, Haemaphysalis longicornis, Haemaphysalis megaspinosa, Ixodes columnae, Ixodes monospinosus, Ixodes nipponensis, Ixodes ovatus, and Ixodes persulcatus. Investigation of rickettsial DNA showed no ticks infected by R. japonica. However, three species of spotted fever group rickettsiae (SFGR) were found in ticks, R. asiatica, R. helvetica, and R. monacensis, confirming Niigata Prefecture as a new endemic area to SFGR. These results highlight the need for public awareness of the occurrence of this tick-borne disease, which necessitates the establishment of public health initiatives to mitigate its spread.

3.
Infect Genet Evol ; 88: 104683, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33348056

RESUMO

Schistosomiasis is a major public health problem that is included in the neglected tropical diseases. The early diagnosis and detection of the pathogen are of critical importance in the control of the disease. The diagnostic techniques in use include the detection of worm's eggs in fecal examination or detection of circulating antigens in immunological based assays. These traditional strategies lack sensitivity in earlier detection of the schistosomiasis. Cell-free DNA (cfDNA) that includes the fragments of parasitic DNA circulating in the body fluids of host offers an alternative mean for the rapid pathogen detection and thus is a useful diagnostic tool. In this study, we explored the usefulness of the mitochondrial cfDNA markers for the diagnosis of schistosomiasis from the experimentally infected hosts (rabbits and mice). In this study we found mitochondrial DNA fragment cytochrome B gene as persistent and useful cfDNA marker for the early detection of schistosomiasis. We evaluated the sensitivity of cfDNA marker with varying numbers of cercaria. Overall, our results suggest that cfDNA markers can be useful for developing a diagnostic tool for the detection of S. japonicum infection.

4.
Pathogens ; 9(12)2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33255924

RESUMO

The current study evaluated the anthelmintic effect of different extracts of Leucaena leucocephala, Parkia platycephala, and Senna alata on trichostrongylid eggs and infective larvae and determined the potential active components of each plant. Dried and macerated plant material was concentrated using rotaevaporation to obtain the crude extract (CE), followed by solvent partitioning to obtain hexanic (HexE), acetatic (AcE), and butanolic (BuE) extracts used for phytochemical analysis and anthelmintic efficacy testing in vitro. All the crude and partitioned extracts tested showed inhibition activity in the hatching of trichostrongylid eggs. Larvicidal efficacy was observed at CE concentrations of 2.5, 5.0, and 7.5 mg/mL for P. platycephala and S. alata. However, L. leucocephala CE did not significantly reduce the number of living larvae in the tested concentrations. Chromatographic analysis revealed several active metabolites; gallic acid, ellagic acid, naringin, morin, and kaempferol on AcE of P. platycephala; gallic acid, rutin, and ellagic acid on BuE of P. platycephala; and gallic acid and naringin on BuE of L. leucocephala. The extracts of P. platycephala, L. leucocephala, and S. alata leaves showed egg hatching inhibition and larvicidal activity, probably produced by tannins and flavonoids, which may act alone or by synergism.

5.
Rev Bras Parasitol Vet ; 29(4): e017820, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33295378

RESUMO

Leishmania infantum infection in cats has been reported in several countries, including Brazil. However, the transmission of visceral leishmaniasis (VL) from cats to another host has not been proven yet. Therefore, the aim of this study was to verify the possibility of L. infantum transmission from cats to dogs. In order to verify the possibility of VL transmission from the cat to the dog, xenodiagnosis was carried out in a VL-positive cat, using 55 female Lutzomyia longipalpis. Five days later, 40 insects were dissected to verify Leishmania infection. The remaining 15 females were fed in a healthy dog. The potential infection of the dog was verified through clinical, serological, parasitological examinations, and PCR, at three, six, and twelve months post-infection. All 55 L. longipalpis females became visibly engorged. Leishmania promastigotes were detected in 27.5% of the dissected insects. Leishmania infection in the dog was confirmed upon first evaluation. DNA sequencing of the parasite isolated from the cat confirmed L. infantum infection and showed 99% similarity with the L. infantum DNA sequences from the dogs. Through this study, it was possible to confirm the L. infantum experimental transmission from a domestic cat to a domestic dog through its biological vector L. longipalpis.

6.
Parasitol Int ; 76: 102096, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32114084

RESUMO

In the present study, we demonstrate that the Japanese macaque (Macaca fuscata) can be used as an effective alternative in vivo model for investigating hypnozoite-induced relapsing infection caused by Plasmodium cynomolgi B strain, and that this model is comparable to the rhesus macaque model. Two female Japanese macaques (JM-1 and JM-2; aged 5 years; weighing about 4.0 kg) were used for the experiment. To produce sporozoites in mosquitoes, blood infected with P. cynomolgi B strain was collected from the donor monkey JM-1 and fed to approximately 200 mosquitoes using the standard artificial membrane feeding method. The isolated sporozoites (2 × 105) were intravenously inoculated into the JM-2 monkey, and the blood stage of the parasite was detected on day 8 after the infection. Chloroquine sulfate (CQ) was intramuscularly administered at a dosage of 6.0 mg/kg into the JM-2 monkey for 6 consecutive days from day 12 onward, after which the parasites disappeared from the peripheral blood. The first relapse occurred on day 26, which was treated again with CQ. Then, the second relapse occurred on day 44, which was cured by CQ treatment followed by the administration of primaquine phosphate (PQ) at a dosage of 1.0 mg/kg/day for 15 days. The JM-2 monkey was observed until 69 days after PQ administration, and there was no relapse during the entire follow-up period. We propose that the Japanese macaque model could contribute not only to drug screening for anti-hypnozoite activity, but could also be used as a powerful tool for investigating hypnozoite biology.


Assuntos
Modelos Animais de Doenças , Macaca fuscata , Malária/parasitologia , Plasmodium cynomolgi/fisiologia , Animais , Feminino , Recidiva
7.
Acta Trop ; 202: 105250, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31678236

RESUMO

Soil-transmitted helminth (STH) infections are important causes of morbidity in poorer areas of developing countries, with high endemicity in Southeast Asia. Humans are most often exposed to the infective forms of STHs in areas with sub-standard sanitation. The number of STH infections globally was estimated at 1.5 billion in 2018. In Indonesia, the prevalence of STH infections ranges from 2.5% to 62.0%. STH and taeniasis infections were evaluated on Samosir Island, North Sumatra, Indonesia. Field surveys were conducted in January 2003, February 2005, and February 2006 in Simanindo Subdistrict, with a subsequent survey conducted in the subdistricts of Simanindo and Ronggurnihuta in September 2015. A total of 371 individuals were screened between 2003 and 2006 and 368 were screened in 2015 (314 from Simanindo and 54 from Ronggurnihuta). Fecal samples were collected and examined microscopically by the Kato-Katz technique. The prevalence of STH infections in Simanindo for the years 2003, 2005, 2006, and 2015 was 41.4%, 52.2%, 55.7%, and 46.8%, respectively. The 2015 prevalence of STH infections in Ronggurnihuta was 66.7%. Taenia asiatica taeniasis prevalence was 3.4% and 2.2% for the years 2003 and 2005, respectively, with no cases detected in 2006 or 2015. The prevalence of STH infections in Simanindo and Ronggurnihuta was similar to other STH prevalence values reported for Indonesia. Country-level values have not changed substantially from those reported in the 1980s and 1990s, where prevalence ranged from 40% to 70%. Improvement of personal hygiene and environmental sanitation for control of STH infections on Samosir Island will require collaboration among multiple sectors.


Assuntos
Doenças Negligenciadas , Solo/parasitologia , Taenia , Teníase/transmissão , Adolescente , Adulto , Animais , Criança , Pré-Escolar , Fezes/parasitologia , Comportamento Alimentar , Feminino , Helmintíase/epidemiologia , Helmintíase/transmissão , Humanos , Indonésia/epidemiologia , Masculino , Doenças Negligenciadas/epidemiologia , Prevalência , Alimentos Crus/parasitologia , Fatores de Risco , Saneamento , Inquéritos e Questionários , Taenia/classificação , Taenia/parasitologia , Teníase/epidemiologia , Adulto Jovem
8.
Rev. bras. parasitol. vet ; 29(4): e017820, 2020. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1144228

RESUMO

Abstract Leishmania infantum infection in cats has been reported in several countries, including Brazil. However, the transmission of visceral leishmaniasis (VL) from cats to another host has not been proven yet. Therefore, the aim of this study was to verify the possibility of L. infantum transmission from cats to dogs. In order to verify the possibility of VL transmission from the cat to the dog, xenodiagnosis was carried out in a VL-positive cat, using 55 female Lutzomyia longipalpis. Five days later, 40 insects were dissected to verify Leishmania infection. The remaining 15 females were fed in a healthy dog. The potential infection of the dog was verified through clinical, serological, parasitological examinations, and PCR, at three, six, and twelve months post-infection. All 55 L. longipalpis females became visibly engorged. Leishmania promastigotes were detected in 27.5% of the dissected insects. Leishmania infection in the dog was confirmed upon first evaluation. DNA sequencing of the parasite isolated from the cat confirmed L. infantum infection and showed 99% similarity with the L. infantum DNA sequences from the dogs. Through this study, it was possible to confirm the L. infantum experimental transmission from a domestic cat to a domestic dog through its biological vector L. longipalpis.


Resumo A infecção por Leishmania infantum em gatos tem sido relatada em vários países, incluindo o Brasil. No entanto, a transmissão da leishmaniose visceral (LV) de gatos para outro hospedeiro ainda não foi comprovada. Portanto, o objetivo deste estudo foi verificar a possibilidade de transmissão de L. infantum de gatos para cães. Para verificar a possibilidade de transmissão da LV do gato para o cão, foi realizado xenodiagnóstico em um gato com LV, utilizando-se 55 fêmeas de Lutzomyia longipalpis. Cinco dias depois, 40 insetos foram dissecados para verificar a infecção por Leishmania. As 15 fêmeas restantes foram alimentadas em um cão saudável. A possível infecção no cão foi verificada por meio de exames clínicos, sorológicos, parasitológicos e PCR, três, seis e doze meses após a infecção. Todas as 55 fêmeas de L. longipalpis ficaram visivelmente ingurgitadas. Promastigotas de Leishmania foram detectadas em 27,5% dos insetos dissecados. A infecção por Leishmania no cão foi confirmada na primeira avaliação. O sequenciamento do DNA do parasito isolado do gato confirmou a infecção por L. infantum e apresentou 99% de similaridade com sequências de DNA de L. infantum de cães. Através deste estudo, foi possível confirmar a transmissão experimental de L. infantum de um gato doméstico para um cão doméstico através do seu vetor biológico L. longipalpis.

9.
PLoS One ; 14(11): e0224617, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31747401

RESUMO

In recent years, the prevalence and infection intensity of Schistosoma japonicum in endemic areas of the Philippines have significantly decreased due to yearly population-based treatment strategies, yet transmission rates remain high and uninterrupted. An important indicator of active disease transmission is the presence of Schistosoma japonicum and its snail intermediate host Oncomelania hupensis quadrasi in freshwater habitats. In this study, we sought to apply a species-specific real-time PCR (qPCR) assay for the detection of S. japonicum and O. hupensis quadrasi in freshwater samples using environmental DNA approach that can complement the commonly utilized malacological survey in determining potential transmission foci in order to have a more effective snail surveillance strategy for schistosomiasis japonica in endemic areas. The newly developed assay was specific to S. japonicum and O. hupensis quadrasi with no amplification detected against non-target trematode Fasciola spp. and snails such as Lymnaea spp., Pomacea canaliculata, and Melanoides spp. that typically co-exist in the same environment. The assay effectiveness was determined using 19 environmental water samples collected from Northern Samar (N = 5 sites), Leyte (N = 11 sites) and Compostela Valley (N = 3 sites) and compared to malacological survey for determining O. hupensis quadrasi snail colonies and snail crushing to visualize S. japonicum cercariae. TaqMan qPCR targeting a short fragment of the cytochrome c oxidase subunit 1 (cox1) gene was positive for S. japonicum in 9 sites, for O. hupensis quadrasi in 9 sites, and for both S. japonicum and O. hupensis quadrasi in 5 sampling sites. Moreover, it was able to detect O. hupensis quadrasi in 3 out of 12 sites found negative and 6 out of 7 sites found positive through malacological survey, and in 4 of the 5 snail sites positive for snails with cercariae. Overall, this method can complement malacological surveys for monitoring of schistosomes in endemic areas of the Philippines, especially those with high risk of human infection.


Assuntos
DNA Ambiental/isolamento & purificação , Monitoramento Epidemiológico , Schistosoma japonicum/isolamento & purificação , Esquistossomose Japônica/prevenção & controle , Caramujos/genética , Animais , Cercárias/genética , Vetores de Doenças , DNA Ambiental/genética , Humanos , Filipinas/epidemiologia , Schistosoma japonicum/genética , Esquistossomose Japônica/epidemiologia , Esquistossomose Japônica/parasitologia , Esquistossomose Japônica/transmissão , Caramujos/parasitologia , Especificidade da Espécie
10.
Pathogens ; 8(4)2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31547610

RESUMO

BACKGROUND: The perpetuation of schistosomiasis japonica in the Philippines depends to a major extent on the persistence of its intermediate host Oncomelania hupensis quadrasi, an amphibious snail. While the malacological survey remains the method of choice in determining the contamination of the environment as evidenced by snails infected with schistosome larval stages, an emerging technology known as environmental DNA (eDNA) detection provides an alternative method. Previous reports showed that O. hupensis quadrasi eDNA could be detected in water, but no reports have been made on its detection in soil. METHODS: This study, thus focused on the detection of O. hupensis quadrasi eDNA from soil samples collected from two selected schistosomiasis-endemic barangays in Gonzaga, Cagayan Valley using conventional and TaqMan-quantitative (qPCR) PCRs. RESULTS: The results show that qPCR could better detect O. hupensis quadrasi eDNA in soil than the conventional method. In determining the possible distribution range of the snail, basic edaphic factors were measured and correlated with the presence of eDNA. The eDNA detection probability increases as the pH, phosphorous, zinc, copper, and potassium content increases, possibly indicating the conditions in the environment that favor the presence of the snails. A map was generated to show the probable extent of the distribution of the snails away from the body of the freshwater. CONCLUSION: The information generated from this study could be used to determine snail habitats that could be possible hotspots of transmission and should, therefore, be targeted for snail control or be fenced off from human and animal contact or from the contamination of feces by being a dumping site for domestic wastes.

11.
Pathogens ; 8(2)2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31137506

RESUMO

Bovine cysticercosis, caused by Taenia saginata metacestodes, is the cause of significant economic losses to the meat production chain by condemnation and downgrading of infected carcasses. It is also a public health issue causing human taeniasis. This study evaluated the occurrence of bovine cysticercosis at the meat inspection procedures in slaughterhouses of south and north regions of the Tocantins State in Brazil. Specimens identified as cysts of T. saginata were collected and analyzed by molecular (PCR) and histopathological techniques. The cysts were collected from March to December of 2010 in slaughterhouses located in the cities of Alvorada (South) and Araguaína (North). The frequency of cystic lesions during the study was 0.033% (53/164,091) with 69.81% of calcified lesions and 30.9% of live cysts at meat inspection. From 14 samples submitted to molecular analysis, 28.57% (4/14) were positive for T. saginata. The histopathological analysis of the non-T. saginata samples showed lesions suggestive of granuloma and hydatid disease. The results indicated that the identification of the etiological agent is difficult by macroscopic inspection, emphasizing the need to associate specific diagnostic methods at meat inspection in abattoirs. In addition, species-specific PCR would be an effective tool for diagnosis, monitoring, and identifying cysticercosis, assisting the conventional tests.

12.
Parasitol Int ; 70: 1-4, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30630115

RESUMO

Yearly, several reports of unknown boats and corpses brought by the Tsushima Current are found ashore Japanese coast. Niigata prefecture had the highest number of the drifting ashore corpses in Japan with 45.7% (16/35) in 2017. Corpses from North Korea, confirmed by documents and photos were autopsied and in 3/16 was possible to recover worms full of eggs, morphologically identified as ascarids. Further molecular analysis of ITS1, 5.8S rDNA and ITS2 sequences confirmed all specimens were Ascaris lumbricoides. The contamination level by Ascaris lumbricoides eggs in the coast, the health impact and consequences of the epidemiological bridging produced by this forced migration in public health should be investigated. Moreover, control of helminthiases might be a necessary task in North Korea.


Assuntos
Ascaríase/epidemiologia , Ascaris lumbricoides/genética , Cadáver , Doenças Transmissíveis Importadas/parasitologia , Patologia Legal , Animais , Ascaríase/transmissão , Ascaris lumbricoides/isolamento & purificação , Autopsia , Doenças Transmissíveis Importadas/transmissão , DNA Ribossômico/genética , República Democrática Popular da Coreia/epidemiologia , Humanos , Japão , Saúde Pública , Navios , Migrantes
13.
Parasite Epidemiol Control ; 4: e00083, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30662968

RESUMO

The time is passing, and the worms are still a major struggle for local people in Asian countries, especially the less empowered and in a situation of social vulnerability. We are working in the field in Laos, Thailand, and the Philippines where the usual control programs based only on human treatment are partially effective. Areas with mass drug administration could diminish, but not eliminate STHs of endemic areas. The persistence of helminthic NTDs in the environment and animal hosts makes the eradication a very difficult task. Great changes in the landscapes of endemic areas, such as construction of dams, can change the fauna and the lifestyle of local people. Those changes can improve infrastructure, but it can also lead to social vulnerability. The challenge, then, is to conceive new and directed control programs for helminthiasis based on multi- and transdisciplinary approaches diminishing the health gap in a globalized world. In this short review, we summarize the actual scenario concerning the main helminths in Southeast Asia and how an environmental DNA approach and the use of GIS could contribute to surveillance and control programs.

14.
Int J Infect Dis ; 76: 130-136, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30201503

RESUMO

OBJECTIVES: Schistosomiasis is an important disease in Madagascar, and several studies on the disease have focused on the occurrence of the parasite in humans. However, the range of the pathogen in the environment and its impact on human infection is difficult to predict. An environmental DNA (eDNA) detection system for Schistosoma mansoni was developed to improve schistosomiasis eco-epidemiology studies. METHODS: Primers and probes were designed and tested in experimental biotopes. The field study was conducted in Maevatanana District of Madagascar. Seven water sources with human use were sampled, with a total of 21 water samples collected. Snails were collected, and patients were examined by ultrasound to determine the occurrence of schistosomiasis in the study area. RESULTS: One water source with active transmission was identified through the detection of S. mansoni eDNA in the water and the intermediate host Biomphalaria pfeifferi collected from the same water source. People with clinical schistosomiasis were found in the area, reinforcing the findings. CONCLUSIONS: The application of eDNA in eco-epidemiology enables the determination of hot spots and safe spots in endemic areas, constituting an alternative ecological tool for follow-up and monitoring of control programs for schistosomiasis, and contributing information on water safety for improving the standard of living of the people in endemic areas.


Assuntos
Biomphalaria/parasitologia , DNA de Helmintos/análise , Schistosoma mansoni/isolamento & purificação , Água/parasitologia , Animais , Ecologia , Humanos , Masculino , Schistosoma mansoni/genética , Esquistossomose mansoni/epidemiologia
15.
PLoS Negl Trop Dis ; 12(2): e0006260, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29420601

RESUMO

Most part of Southeast Asia is considered endemic for human-infecting Taenia tapeworms; Taenia solium, T. saginata, and T. asiatica. However, until now there was no report of the occurrence of human cases of T. asiatica in Lao PDR. This study, conducted in Savannakhet Province, Lao PDR, microscopically examined a total of 470 fecal samples by Kato Katz method and found 86% of people harboring at least one helminth. Hookworms were detected in 56% of the samples besides Opisthorchis like eggs (42%), Trichuris trichiura (27%), Ascaris spp. (14%), and Taenia spp. (4%) eggs. Serology for cysticercosis showed 6.8% positives with results varying from 3% to 14.3% in Ethnic School students and Kalouk Kao village respectively. Species-specific PCR targeting mitochondrial DNA (mtDNA) of 28 tapeworms, recovered from 16 patients, revealed T. solium (n = 2), T. saginata (n = 21), and T. asiatica (n = 5). Two patients were confirmed to be coinfected with T. saginata and T. asiatica, indicating the endemicity of the 3 human Taenia in Lao PDR. However, nucleotide sequencing of a nuclear DNA gene, DNA polymerase delta (pold) revealed that all the tapeworms identified as T. asiatica using mtDNA had T. saginata type allele at pold locus, demonstrating that they are not "pure T. asiatica" but the hybrid descendants between the two species, confirming the wide distribution of hybrids of T. saginata/ T. asiatica in Southeast Asia. The high prevalence of several helminthic NTDs in east Savannakhet area even with conventional control measures indicates the importance to establish wide and multifaceted health programs to sustainably improve the quality of life of the populations living in these communities.


Assuntos
Cisticercose/epidemiologia , Doenças Endêmicas , Doenças Negligenciadas/epidemiologia , Taenia/isolamento & purificação , Teníase/epidemiologia , Adolescente , Adulto , Idoso , Animais , Anticorpos Anti-Helmínticos/sangue , Criança , Cisticercose/sangue , Cisticercose/tratamento farmacológico , Cisticercose/parasitologia , DNA de Helmintos/genética , DNA Mitocondrial/genética , Fezes/parasitologia , Feminino , Humanos , Laos , Masculino , Pessoa de Meia-Idade , Doenças Negligenciadas/parasitologia , Reação em Cadeia da Polimerase , Prevalência , Análise de Sequência de DNA , Especificidade da Espécie , Taenia/classificação , Taenia/genética , Taenia/imunologia , Taenia saginata/genética , Taenia saginata/imunologia , Taenia saginata/isolamento & purificação , Taenia solium/genética , Taenia solium/imunologia , Taenia solium/isolamento & purificação , Teníase/parasitologia , Adulto Jovem
16.
Int J Parasitol ; 47(14): 971-979, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28797792

RESUMO

The specific status of Echinococcus canadensis has long been controversial, mainly because it consists of the mitochondrial lineages G6, G7, G8 and G10 with different host affinity: G6 (camel strain) and G7 (pig strain) with domestic cycles and G8 (cervid strain) and G10 (Fennoscandian cervid strain) with sylvatic or semi-domestic cycles. There is an argument whether the mitochondrial lineages should be recognised as separate species which correspond to the biological or epidemiological aggregation. In the present study, the specific status of E. canadensis was investigated using mitochondrial DNA and single copy nuclear DNA markers. Nucleotide sequences of complete mitochondrial cytochrome c oxidase subunit 1 (cox1) and partial nuclear phosphoenolpyruvate carboxykinase (pepck) and DNA polymerase delta (pold) were determined for 48 isolates of E. canadensis collected from different hosts in a wide range of regions. The mitochondrial phylogeny of cox1 showed that all the isolates were clearly divided into three clades corresponding to G6/G7, G8 and G10. Five and three alleles were confirmed at pepck and pold loci, respectively. These alleles were generally divided into two groups corresponding to G6/G7 or G8 and G10. However, allele sharing was confirmed among individuals belonging to different lineages. The allele sharing occurred primarily in regions where different mitochondrial DNA lineages were found in sympatry. The resultant nuclear mitochondrial discordance suggests the genetic exchangeability among E. canadensis isolates belonging to different lineages. An apparently mosaic parasite fauna that reflects faunal mixing due to natural and anthropogenic disturbance, including introductions and invasion, precludes us from designating each of G6/G7, G8 and G10 into a different species.


Assuntos
DNA de Helmintos/genética , DNA Mitocondrial/genética , Echinococcus/genética , Alelos , Animais , Sequência de Bases , Núcleo Celular/enzimologia , Núcleo Celular/genética , DNA Polimerase III/genética , DNA de Helmintos/química , DNA Mitocondrial/química , Echinococcus/classificação , Echinococcus/enzimologia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Marcadores Genéticos/genética , Haplótipos , Humanos , Filogenia , Polimorfismo Genético , Estudos Retrospectivos , Alinhamento de Sequência
17.
Acta Trop ; 169: 1-7, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28108370

RESUMO

Opisthorchiasis, which can lead to cholangiocarcinoma in cases of chronic infection, is a major public health problem in Southeast Asian countries. The trematode, Opisthorchis viverrini, is the causative agent of the disease. Accurate and rapid monitoring of O. viverrini is crucial for disease prevention and containment. Therefore, in this study we sought to develop a novel species-specific real-time PCR assay for detecting O. viverrini using environmental DNA (eDNA). The diagnostic sensitivity of the newly developed real-time PCR assay was similar to that of the traditional PCR assay for 50 fecal samples collected in Lao PDR (21 and 19 samples were positive by real-time PCR and traditional PCR, respectively). The efficacy of eDNA analysis and its applicability in the field were tested using a total of 94 environmental water samples collected from 44 sites in Savannakhet, Lao PDR during May and October 2015 and February 2016. O. viverrini eDNA was detected in five samples by real-time PCR, indicating the presence of the fluke in the area and the risk of infection for individuals consuming fish from these water sources. The application of eDNA analysis would facilitate the identification of O. viverrini endemic hotspots and contribute to the ecological control of opisthorchiasis, and this strategy can be applied to other eukaryotic water pathogens.


Assuntos
Monitoramento Ambiental/métodos , Opisthorchis/genética , Opisthorchis/isolamento & purificação , Água/parasitologia , Animais , Colangiocarcinoma/parasitologia , DNA de Helmintos/análise , DNA de Helmintos/genética , Peixes/parasitologia , Opistorquíase/parasitologia , Reação em Cadeia da Polimerase em Tempo Real , Alimentos Marinhos/parasitologia , Especificidade da Espécie
18.
Korean J Parasitol ; 54(4): 543-7, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27658609

RESUMO

In the present study, we report on the occurrence of paramphistomes, Fischoederius cobboldi and Paramphistomum epiclitum, in Lao PDR with the basis of molecular data. Parasite materials were collected from bovines bred in Ban Lahanam area, Savannakhet Province, Lao PDR at Lahanam public market. Morphological observations indicated 2 different species of paramphistomes. The mitochondrial gene cox1 of the specimens was successfully amplified by PCR and DNA sequencing was carried out for diagnosis of 11 specimens. Pairwise alignment of cox1 sequences were performed and confirmed F. cobboldi and P. epiclitum infecting bovines in Laos. Although there were many limiting points, as the small number of worm samples, and the restricted access of the animal host materials, we confirmed for the first time that 2 species of paramphistomes, F. cobboldi and P. epiclitum, are distributed in Lao PDR. More studies are needed to confirm the paramphistome species present in Savannakhet and its hosts to clear the natural history of these parasites of ruminants in the region and measure the impact of this parasite infection in the life and health of the local people.


Assuntos
Parasitologia de Alimentos , Paramphistomatidae/isolamento & purificação , Rúmen/parasitologia , Animais , Bovinos , Complexo IV da Cadeia de Transporte de Elétrons/genética , Laos , Microscopia , Paramphistomatidae/anatomia & histologia , Paramphistomatidae/classificação , Paramphistomatidae/genética , Análise de Sequência de DNA
19.
Rev Bras Parasitol Vet ; 23(1): 80-4, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24728365

RESUMO

Trichostrongylids infection has gained significant public health importance since Trichostrongylus spp. infections have been reported in humans in Lao PDR. In this study, gastrointestinal nematodes were identified and the intensity of infections was determined in goats and cattle, which are animals greatly used for meat production in Lahanam Village, Lao PDR. The total number of goats and bovines was 23 and 29, respectively, pertaining to 32 households surveyed in the area. Feacal samples were randomly collected from 14 goats and 11 bovines. Ninety three percent (13/14) of goats and 36% (3/11) of cattle were infected, with an average of 1,728 and 86 eggs per gram of faeces (EPG), respectively. Coproculture showed Trichostrongylus spp. (goats 16%; bovines 48%), Haemonchus spp. (goats 69%; bovines 37%), Cooperia spp. (bovines 8%) and Oesophagostomum spp. (goats 15%; bovines 6%). After performing the necropsy on an adult goat, Trichuris spp. was also found. We confirmed the presence of Oesophagostomum spp., H. contortus and T. colubriformis by morphology and DNA sequencing analysis of the ITS region of rDNA. Due to interactions between humans and goats in Lahanam Village and high EPG results, the diagnosis of species and the intensity of gastrointestinal nematode infection in these animals are important public-health issues. Other ruminant parasites, such as Oesophagostomum and Haemonchus, found in caprines and bovines, are reported to be causes of zoonosis and their presence in humans should be investigated in future field surveys in this area.


Assuntos
Doenças dos Bovinos/parasitologia , Doenças Transmitidas por Alimentos/parasitologia , Doenças das Cabras/parasitologia , Infecções por Nematoides/veterinária , Animais , Bovinos , Clima , Cabras , Laos , Zoonoses
20.
Parasitol Int ; 60(1): 108-10, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21109020

RESUMO

Cysticercosis caused by infection with embryonated eggs of the pork tapeworm Taenia solium is an important cause of neurological disease worldwide. Based on the phylogenetic analysis of mitochondrial DNA, the pathogen has been divided into two geographic clades, corresponding to Afro-American and Asian genotypes. In this study the genotyping of T. solium was carried out by using the nuclear DNA sequences of the immunodiagnostic antigen genes Ag1V1 and Ag2. The two geographic genotypes were supported by the Ag2 sequences, especially showing unique substitutions in each of the genotypes. It seems likely that the Ag2 may be a novel nuclear DNA marker to distinguish the two geographic genotypes of T. solium.


Assuntos
Cisticercose/parasitologia , Taenia solium/classificação , Taenia solium/genética , América/epidemiologia , Animais , Antígenos de Helmintos/genética , Ásia/epidemiologia , Sequência de Bases , Núcleo Celular/genética , Cisticercose/diagnóstico , Cisticercose/epidemiologia , Marcadores Genéticos , Genética Populacional , Genótipo , Geografia , Dados de Sequência Molecular , Análise de Sequência de DNA
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