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1.
Infect Genet Evol ; 95: 105085, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34530156

RESUMO

Blastocystis is a commonly encountered gastrointestinal protozoan in humans and animals with uncertain pathogenicity. Despite its potential public health impact, epidemiological data regarding the prevalence and molecular subtype (ST) distribution of Blastocystis have been rarely reported. Among Blastocystis STs, ST1-ST4 are common in humans, including healthy and immunodeficient populations. According to the Chi-squared (χ2) association based on the data compiled for this cross-sectional study, the presence of ST1 is associated with asymptomatic infection, whereas the presence of ST4 is associated with symptomatic infection. However, cross-sectional studies cannot clarify the potential pathogenicity of Blastocystis, unlike in vivo and in vitro studies. Poor hygiene, poor sanitation and zoonotic transmission are possible factors associated with high Blastocystis prevalence, although this protozoan may be part of the normal healthy human gastrointestinal microbiota. This review covers the prevalence, STs and distribution of Blastocystis infection in humans. Thus, future epidemiological and subtyping studies could reveal new STs in humans as well as possible associations of STs with disease, drug resistance and related mechanisms such as protease activity. These associations with proper ST identification may facilitate the control of potential threats to host health, including the direct pathogenic effects of Blastocystis or alterations of the gastrointestinal microbiome.

2.
Parasitol Res ; 120(8): 2887-2895, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34331137

RESUMO

Few data are available on the genetic identity of enteric protists Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi in humans in Thailand. In this study, 254 stool samples were collected from primary school children from Ratchaburi Province at the Thai-Myanmar border and examined for Cryptosporidium spp., G. duodenalis, E. bieneusi and Cyclospora cayetanensis using PCR techniques. The genotype identity of the pathogens was determined by DNA sequence analysis of the PCR products. Cryptosporidium felis was found in 1 stool sample, G. duodenalis in 19 stool samples, and E. bieneusi in 4 stool samples. For G. duodenalis, sub-assemblage AII was the dominant genotype, but one infection with assemblage F was found. The E. bieneusi genotypes found included known genotypes D and J, and one novel genotype (HPTM1). Cyclospora cayetanensis was not detected in any samples. Results of the preliminary study indicate that children at the Thai-Myanmar border from Ratchaburi Province, Thailand are infected with diverse zoonotic genotypes of Cryptosporidium spp., G. duodenalis, and E. bieneusi.


Assuntos
Criptosporidiose , Cryptosporidium , Enterocytozoon , Giardia lamblia , Giardíase , Microsporidiose , Criança , Criptosporidiose/epidemiologia , Cryptosporidium/genética , Cryptosporidium/isolamento & purificação , Enterocytozoon/genética , Enterocytozoon/isolamento & purificação , Fezes , Genótipo , Giardia lamblia/genética , Giardia lamblia/isolamento & purificação , Giardíase/epidemiologia , Humanos , Microsporidiose/epidemiologia , Mianmar , Instituições Acadêmicas , Tailândia
3.
BMC Vet Res ; 17(1): 203, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34078384

RESUMO

BACKGROUND: Pentatrichomonas hominis inhabits the digestive tracts of several vertebrates, such as humans, monkeys, pigs, dogs, cats and rats. This protozoan was originally considered a commensal of the digestive tract but has subsequently been identified as a potential zoonotic parasite and a causative agent of diarrhoea. Molecular techniques are considered more sensitive and specific to detect P. hominis. This study aimed to determine the presence and genetic diversity of P. hominis in animals in Thailand. A total of 403 faecal samples were collected from 119 cats, 55 dogs, 73 goats, 35 monkeys, 55 cattle and 66 pigs, and the presence of P. hominis was determined using the nested polymerase chain reaction method. Sequence analysis of small-subunit ribosomal RNA genes was used to determine the genotype of the organism. RESULTS: Twenty-six samples (26/403, 6.45%) were positive for P. hominis. The highest prevalence was found in cats (21/119; 17.65%), followed by cattle (3/55; 5.45%) and dogs (2/55; 3.64%). Seven out of 26 nucleotides demonstrated 100% sequence identity with existing sequences; additionally, 16 novel sequence patterns were identified. All nucleotide sequences of P. hominis-positive samples were shown in the same branch with the previously described P. hominis sequences found in humans, dogs and goat. CONCLUSION: This is the first study on P. hominis infections in animals in Thailand. Our findings revealed that the prevalence of P. hominis was significantly higher in cats than in cattle and dogs. Cats were the main reservoir host; however, P. hominis can infect several kinds of animals. Therefore, the proper waste management of animals is necessary to reduce and prevent infection in the community.


Assuntos
Infecções Protozoárias em Animais/parasitologia , Trichomonadida/classificação , Animais , Gatos/parasitologia , Bovinos/parasitologia , Cercopithecidae/parasitologia , Cães/parasitologia , Cabras/parasitologia , Filogenia , Prevalência , Infecções Protozoárias em Animais/epidemiologia , Suínos/parasitologia , Tailândia/epidemiologia
4.
Artigo em Inglês | MEDLINE | ID: mdl-33260351

RESUMO

Diabetes mellitus (DM) is a major global public health problem with an increasing prevalence. DM increases the risk of infections caused by bacteria, fungi, viruses, and parasites. We examined the prevalence, subtypes, and risk factors of Blastocystis infection in patients with and without DM in central Thailand. Stool samples and questionnaires were obtained from 130 people in the DM group and 100 people in the non-DM group. Blastocystis infection was identified via a nested polymerase chain reaction and subtyped via sequencing of the partial small-subunit ribosomal RNA (SSU rRNA) gene. Analysis of potential risk factors was conducted via binary logistic regression. The overall prevalence of Blastocystis infection was 10.8%, including rates of 9% and 12.3% in the non-DM and DM groups, respectively. The most prevalent subtype was ST3, followed by ST1, and ST4. Factors that potentially increased the risk of Blastocystis infection include patients being >65 years old, the presence of DM, a DM duration of ≥10 years, a low level of education, and animal ownership. In conclusion, this is the first study of Blastocystis infection in DM, and a high prevalence was found among this population. Therefore, health education promoting sanitation and hygiene is necessary to reduce and prevent infection in the community.


Assuntos
Infecções por Blastocystis , Blastocystis , Complicações do Diabetes , Diabetes Mellitus , Idoso , Animais , Blastocystis/genética , Infecções por Blastocystis/complicações , Infecções por Blastocystis/epidemiologia , DNA de Protozoário , Diabetes Mellitus/epidemiologia , Fezes , Feminino , Variação Genética , Humanos , Masculino , Filogenia , Prevalência , Tailândia/epidemiologia
5.
Insects ; 11(4)2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32260093

RESUMO

Crude extracts and essential oils of A. conyzoides were tested with larva and adult stages of Ae. aegypti mosquitoes to determine their insecticidal properties. The crude extracts and essential oils came from three varieties of A. conyzoides (with white flowers, purple flowers, or white-purple flowers) and from two places on each plant (leaves and flowers), giving six types overall: leaf-white (LW); leaf-purple (LP); leaf white-purple (LW-P); flower-white (FW); flower-purple (FP); and flower white-purple (FW-P). Chemical constituents and components of the essential oils were identified using gas chromatography-mass spectrometry (GC-MS). Electron microscopic and histopathological studies were performed to determine the toxicological effects on mosquitoes in terms of morphological alterations. The six types of crude extracts exhibited no activity against individuals in the larval stages. However, six types of essential oils were effective against adult Ae. aegypti females. The mortality of adult Ae. aegypti females was higher from leaf extracts, particularly LP (median lethal dose, LD50 = 0.84%). The number of chemical constituents identified by GC-MS was high in flowers, especially W-P. Precocene I was the most abundant chemical component among the five types of essential oils, except in LP, in which precocene II was the most abundant. Histopathological alterations in adult Ae. aegypti females included compound eye degeneration, muscular damage with cellular infiltration, gut epithelial degeneration and necrosis, pyknotic nuclei in the malpighian epithelium and ovarian cell degeneration. FW and FP plant types exhibited the highest severity of histopathological alterations in mosquitoes compared with other plants, probably owing to the presence of monoterpene compounds in their tissues. The present study demonstrated LP plant extracts from A. conyzoides could be effective adulticides against adult Ae. aegypti. As natural products are biodegradable and exhibit low toxicity to mammalian and non-target organisms, they are suitable candidates for use in vector control programmes.

6.
BMC Complement Med Ther ; 20(1): 63, 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32111225

RESUMO

BACKGROUND: Giardia duodenalis causes giardiasis in humans, particularly in developing countries. Despite the availability of treatments, resistance to some of the commercial anti-Giardia drugs has been reported in addition to their harmful side effects. Therefore, novel treatments for giardiasis are required. In this study, we aimed to assess the in vitro activity of crude extracts of Ageratum conyzoides against G. duodenalis trophozoites. METHODS: Plants were classified into three groups based on their flower colors: white (W), purple (P), and white-purple (W-P). Plants were separately cut into leaf (L) and flower (F) parts. Changes in internal organelle morphology of trophozoites following exposure to crude extracts were assessed using transmission electron microscopy (TEM). In subsequent experiments, efficacy of the most active essential oils from crude extracts [half maximal inhibitory concentrations (IC50) ≤ 100 µg/mL] against G. duodenalis trophozoites was tested. In vitro anti-Giardia assays using essential oils were performed in the same way as those performed using crude extracts. RESULTS: LW-P and FP extracts showed high activity (IC50 ≤ 100 µg/mL) against G. duodenalis trophozoites, with IC50 ± SD values of 45.67 ± 0.51 and 96.00 ± 0.46 µg/mL, respectively. In subsequent experiments, IC50 ± SD values of LW-P and FP essential oils were 35.00 ± 0.50 and 89.33 ± 0.41 µg/mL, respectively. TEM revealed the degeneration of flagella and ventral discs of G. duodenalis trophozoites following exposure to crude extracts. CONCLUSION: Crude LW-P and FP extracts of A. conyzoides showed the highest activity against G. duodenalis. Exposure to crude extract induced changes in the flagella and ventral discs of G. duodenalis trophozoites, which play important roles in attachment to the surface of mucosal cells. Our results suggest that the tested extracts warrant further research in terms of their efficacy and safety as giardiasis treatment.


Assuntos
Ageratum/química , Giardia lamblia/efeitos dos fármacos , Giardíase/tratamento farmacológico , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Trofozoítos/efeitos dos fármacos , Cromatografia Gasosa , Giardia lamblia/ultraestrutura , Espectrometria de Massas , Microscopia Eletrônica de Transmissão , Tailândia , Trofozoítos/ultraestrutura
7.
BMC Infect Dis ; 19(1): 808, 2019 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-31521133

RESUMO

BACKGROUND: Enterocytozoon bieneusi and Cryptosporidium spp. are prevalent zoonotic parasites associated with a high burden among children. To date only limited molecular epidemiological data on E. bieneusi and Cryptosporidium spp. in humans living in Thailand has been published. METHODS: PCR-based tools were used to detect and characterize E. bieneusi and Cryptosporidium spp. The internal transcribed spacer (ITS) region of the rRNA gene was used to investigate E. bieneusi, and the small subunit (SSU) rRNA gene was used to investigate Cryptosporidium spp., and 697 fecal samples from villagers and school children in rural areas in Thailand were analyzed. RESULTS: The infection rates were 2.15% (15/697) for E. bieneusi and 0.14% (1/697) for Cryptosporidium spp. The prevalence of E. bieneusi was significantly high in Loei province. Sequence analysis indicated that the Cryptosporidium isolate was C. parvum. Nine E. bieneusi genotypes were identified, EbpC, Peru12, TMH6, TMH3, TMH7, H, D, and two novel genotypes TMLH1 and TMLH2. E. bieneusi prevalence was significantly higher in male participants than in female participants, and in children aged 3-15 years than in participants aged > 15 years. CONCLUSIONS: The prevalence, genotypes, and zoonotic potential of E. bieneusi were found to vary significantly high even in one country. Transmission routes and key animal carriers of E. bieneusi may be associated with differences in hygiene, sanitation, and cultural behaviors. Further molecular studies including longitudinal studies will be required to unveil epidemiological characteristics of these opportunistic intestinal protozoa in all over the countries.


Assuntos
Criptosporidiose/epidemiologia , Cryptosporidium/classificação , Enterocytozoon/classificação , Microsporidiose/epidemiologia , Zoonoses/epidemiologia , Adolescente , Animais , Gatos , Criança , Pré-Escolar , Estudos Transversais , Criptosporidiose/parasitologia , Criptosporidiose/transmissão , Cryptosporidium/genética , Cryptosporidium/isolamento & purificação , Enterocytozoon/genética , Enterocytozoon/isolamento & purificação , Fezes/parasitologia , Feminino , Genótipo , Humanos , Higiene , Masculino , Microsporidiose/parasitologia , Microsporidiose/transmissão , Filogenia , Prevalência , População Rural , Saneamento , Suínos , Tailândia/epidemiologia , Zoonoses/transmissão
8.
BMC Vet Res ; 15(1): 308, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31462318

RESUMO

BACKGROUND: Enterocytozoon bieneusi has been increasingly reported to infect domestic animals and humans, with human infections primarily reported as zoonotic in origin. The aim of the present study was to determine the presence and genotype of E. bieneusi in humans and domestic animals in central Thailand by testing stool samples of 200 apparently healthy humans, 73 goats, 60 cattle and 65 pigs using nested-PCR/ sequence analysis based on the ITS region of SSU rRNA genes. RESULTS: E. bieneusi tested positive in 2 (1%) of the 200 stool samples collected from humans and 56 (28.3%) of the 198 stool samples collected from domestic animals. The highest prevalence of E. bieneusi was observed in pigs (39/65, 60%), followed by goats (14/73, 19.2%) and cattle (3/60, 5%). Seven novel E. bieneusi genotypes were identified, which were named GoatAYE1-4 and PigAYE1-3 and clustered in either zoonotic Group 1 or Group 2. Moreover, eleven previously described E. bieneusi genotypes were also identified (O, D, H, SX1, CHC8, CHG3, CS-10, SHZC1, LW1, WildBoar5, and EbpC). All novel genotypes exhibited zoonotic potential from a phylogenetic analysis of ITS region. CONCLUSION: Our data showed that the prevalence of E. bieneusi is low in apparently healthy individuals and higher in pigs than cattle and goats. This study provides baseline data useful for controlling and preventing E. bieneusi infection in farm communities, where pigs and goats appear to be the major reservoir of E. bieneusi. The results of our study support the view that E. bieneusi is a zoonotic pathogen that should be considered a potential public health threat.


Assuntos
Doenças dos Bovinos/microbiologia , Enterocytozoon/isolamento & purificação , Doenças das Cabras/microbiologia , Microsporidiose/veterinária , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Criança , Pré-Escolar , Estudos Transversais , Enterocytozoon/genética , Genótipo , Doenças das Cabras/epidemiologia , Cabras , Humanos , Lactente , Microsporidiose/epidemiologia , Microsporidiose/microbiologia , Pessoa de Meia-Idade , Filogenia , Prevalência , Tailândia/epidemiologia , Adulto Jovem , Zoonoses
9.
Parasitol Int ; 67(6): 824-828, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30165261

RESUMO

Blastocystis is a unicellular protist most commonly detected in humans and a variety of animals. The predominant mode of its transmission is the fecal-oral route, but its zoonotic potential is not completely understood. The objective of this study was to determine the presence and genetic diversity of Blastocystis on pig farms in Nakhon Pathom Province, Central Thailand. A total of 154 human and 90 pig stool samples were collected and analyzed. Nested PCR detected Blastocystis in 35.55% of the pig samples and 6.49% of the human samples. Subtyping based on regions of the small-subunit ribosomal RNA (SSU rRNA) gene identified three Blastocystis subtypes in pigs and humans: ST1, ST3, and ST5. Blastocystis ST5 was the predominant subtype, followed by ST1 and then ST3. All the sequences from the Blastocystis-positive samples from both pigs and humans were closely related. This study reveals a possibility of low host specificity of Blastocystis STs (ST1, ST3 and ST5) on pig farms in Thailand. We tentatively suggest that close contact with or exposure to pig stools may be a significant source of Blastocystis detected in pig handlers. Further studies are required to confirm the zoonotic transmission of this organism in Thailand, because pigs may play an important role in the transmission of Blastocystis.


Assuntos
Infecções por Blastocystis/veterinária , Blastocystis/genética , Variação Genética , Doenças dos Suínos/epidemiologia , Criação de Animais Domésticos , Animais , Infecções por Blastocystis/epidemiologia , Infecções por Blastocystis/parasitologia , DNA de Protozoário/genética , Filogenia , Prevalência , Suínos , Doenças dos Suínos/parasitologia , Tailândia/epidemiologia
10.
Infect Genet Evol ; 65: 107-111, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30003970

RESUMO

Blastocystis is a common intestinal pathogen of humans and a variety of animals, with various host-specific subtypes. The aim of this study was to determine the prevalence and subtype distribution of Blastocystis in humans and domestic animals, Thailand. 113 stool samples were collected from pigs, goats, and cattle in Ayutthaya Province (AP; central Thailand) and 218 stool samples were collected from pigs, dogs, cats, chickens, and humans in Kanchanaburi Province (KP; western Thailand). Blastocystis was detected by nested PCR targeting the SSU rRNA gene. Subtypes were identified by DNA sequencing, and phylogenetic analysis was conducted. The overall prevalence of Blastocystis in animals was 76.1% (86/113) and 11.88% (12/101) in AP and KP, respectively, and the prevalence in humans was 12.82% (15/117) in KP. The prevalence of Blastocystis in the AP and KP pigs were 87.88% (29/33) and 20.37% (11/54), respectively. Blastocystis ST5 was the most abundant in pigs in both areas while Blastocystis ST10 and ST12 were most frequently found in cattle and goats. In addition, low percentage of Blastocystis ST1 and Blastocystis ST14 were found in pigs and goats, respectively. In this study, Blastocystis ST3, followed by ST2 and ST1 were predominantly found in humans. In conclusion, pigs may be a natural host of Blastocystis and this ST may be the pig-adapted ST in the studied areas, in this study.


Assuntos
Infecções por Blastocystis/epidemiologia , Infecções por Blastocystis/parasitologia , Blastocystis , Doenças Parasitárias em Animais/epidemiologia , Doenças Parasitárias em Animais/parasitologia , Animais , Blastocystis/classificação , Blastocystis/genética , Bovinos , DNA de Protozoário , Humanos , Filogenia , Suínos , Tailândia/epidemiologia
11.
Parasit Vectors ; 10(1): 394, 2017 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-28835287

RESUMO

BACKGROUND: Dogs are the definitive hosts of Neospora caninum and play an important role in the transmission of the parasite. Despite the high sensitivity of existing molecular tools such as quantitative real-time PCR (qPCR), these techniques are not suitable for use in many countries because of equipment costs and difficulties in implementing them for field diagnostics. Therefore, we developed a simplified technique, loop-mediated isothermal amplification (LAMP), for the rapid visual detection of N. caninum. METHODS: LAMP specificity was evaluated using a panel containing DNA from a range of different organisms. Sensitivity was evaluated by preparing 10-fold serial dilutions of N. caninum tachyzoites and comparing the results with those obtained using qPCR. Assessment of the LAMP results was determined by recognition of a colour change after amplification. The usefulness of the LAMP assay in the field was tested on 396 blood and 115 faecal samples from dogs, and one placenta from a heifer collected in Lopburi, Nakhon Pathom, Sa Kaeo, and Ratchaburi provinces, Thailand. RESULTS: Specificity of the LAMP technique was shown by its inability to amplify DNA from non-target pathogens or healthy dogs. The detection limit was the equivalent of one genome for both LAMP and qPCR. LAMP and qPCR detected positive N. caninum infection in 15 of 396 (3.8%) blood samples; LAMP detected 9/115 (7.8%) positive faecal samples, while qPCR detected 5/115 (4.3%) positive faecal samples. The placental tissue was shown to be positive by both techniques. Agreement between LAMP and qPCR was perfect in blood samples (kappa value, 1.00) and substantial in faecal samples (kappa value, 0.697). CONCLUSIONS: This is the first known LAMP assay developed for the amplification of N. caninum. The technique effectively and rapidly detected the parasite with high sensitivity and specificity and was cost-effective. This assay could be used in the field to confirm the diagnosis of canine or bovine neosporosis.


Assuntos
Coccidiose/veterinária , Doenças do Cão/diagnóstico , Neospora/virologia , Técnicas de Amplificação de Ácido Nucleico/métodos , Animais , Coccidiose/diagnóstico , Coccidiose/parasitologia , Colorimetria , Corantes/metabolismo , Primers do DNA , Doenças do Cão/parasitologia , Cães , Fezes/parasitologia , Genes de Protozoários , Limite de Detecção , Técnicas de Diagnóstico Molecular , Neospora/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sensibilidade e Especificidade , Temperatura , Tailândia
12.
Vet Parasitol ; 233: 73-79, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28043391

RESUMO

Enterocytozoon bieneusi is an opportunistic intestinal pathogen infecting humans and a variety of animals. Its mode of transmission and zoonotic potential are not completely understood. E. bieneusi has been frequently identified in pigs. The objective of our study was to investigate E. bieneusi in pigs and humans in Western and Central Thailand to determine its presence, genetic diversity, and zoonotic potential. A total of 277 human and 210 pig faecal samples were collected and analysed. E. bieneusi was found in 5.4% and 28.1% of human and pig samples, respectively, by nested PCR. Genotyping based on the internal transcribed spacer regions of the small subunit ribosomal RNA demonstrated three known genotypes (D, H, PigEb10) and eight novel genotypes (TMH1-8) in humans, and five known genotypes (D, EbpA, EbpC, H, O) and 11 novel genotypes (TMP1-11) in pigs. All known genotypes identified in humans and pigs had zoonotic potential. Further studies are needed to evaluate zoonotic risk of novel genotypes, as pigs may play an important role in the transmission of E. bieneusi.


Assuntos
Enterocytozoon/genética , Microsporidiose/parasitologia , Doenças dos Suínos/parasitologia , Zoonoses/parasitologia , Animais , DNA Espaçador Ribossômico/genética , Enterocytozoon/patogenicidade , Fezes/parasitologia , Variação Genética , Genótipo , Humanos , Microsporidiose/transmissão , Suínos , Doenças dos Suínos/transmissão , Tailândia , Zoonoses/transmissão
13.
Korean J Parasitol ; 54(4): 455-60, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27658597

RESUMO

Blastocystis is a common zoonotic enteric protozoan that has been classified into 17 distinct subtypes (STs). A cross-sectional study was conducted to determine the prevalence and subtype distributions of Blastocystis in villagers living along the Chao Phraya River, Ayutthaya Province, Thailand, and to assess the risk of zoonotic infection. In total, 220 stool samples were collected, and DNA was extracted. PCR and sequencing were performed with primers targeting the small-subunit ribosomal RNA (SSU rRNA) genes. Blastocystis was present in 5.9% (13/220) of samples, and ST3 (5.0%; 11/220) was the predominant subtype, followed by ST2 (0.45%; 1/220) and ST6 (0.45%; 1/220). Phylogenetic trees were constructed with the maximum-likelihood method based on the Hasegawa-Kishino-Yano + G + I model, neighbor-joining, and maximum parsimony methods. The percentage of bootstrapped trees in which the associated taxa clustered together was relatively high. All the sequences of the Blastocystis-positive samples (KU051524-KU051536) were closely related to those from animals (pig, cattle, and chicken), indicating a zoonotic risk. Therefore, the villagers require proper health education, especially regarding the prevention of parasitic infection, to improve their personal hygiene and community health. Further studies are required to investigate the Blastocystis STs in the animals living in these villages.


Assuntos
Infecções por Blastocystis/epidemiologia , Infecções por Blastocystis/parasitologia , Blastocystis/classificação , Blastocystis/genética , Variação Genética , Genótipo , Adolescente , Adulto , Idoso , Blastocystis/isolamento & purificação , Criança , Pré-Escolar , Análise por Conglomerados , Estudos Transversais , DNA de Algas/química , DNA de Algas/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Fezes/parasitologia , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Filogenia , Prevalência , RNA Ribossômico 18S/genética , Rios , Análise de Sequência de DNA , Tailândia/epidemiologia , Adulto Jovem
14.
Asian Pac J Trop Med ; 9(6): 562-6, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27262067

RESUMO

OBJECTIVE: To determine the ability of oysters to trap and maintain viable Cryptosporidium oocysts, and the feasibility of Cryptosporidium multiplication in oysters' organs. METHODS: Seventy oysters were raised in experimentally seeded natural seawater for up to 3 months, with weekly oocysts inoculations. Cryptosporidium oocysts, viable and non-viable, as well as other stages were detected using two immunofluorescence vital staining techniques (Sporo-Glo and Merifluor(®)) with confocal microscopy. Viability rate at various times after inoculations were calculated. RESULTS: Cryptosporidium oocysts were found most concentrated in oysters' digestive organs than in gill and water inside the oysters. Oocysts numbers were 857.33 at 24 h after inoculation and strikingly decreased to 243.00 and 126.67 oocysts at 72 h and 7 days, respectively. The oocysts in oyster were also less viable over time; 70%, 60% and 30% viable at 24 h, 72 h and 7 days after inoculation, respectively. At 77 days, the number of oocysts was very low and none was found at 84 days onwards. Although some oocysts were ruptured with released sporozoites, there was no evidence throughout the study of sporozoites multiplication to indicate that oyster is a biological host. Despite the significant reduction in oocysts number after 7 days of inoculation, the remained viable oocysts can still cause cryptosporidiosis. CONCLUSION: The findings confirm that Cryptosporidium parvum does not multiply in oyster, and is therefore not a biological host. Nevertheless, the results suggest that oyster can be an effective transmission vehicle for Cryptosporidium oocysts, especially within 24-72 h of contamination, with viable oocysts present at up to 7 days post infection. Unless consuming well-cooked oyster dishes, eating raw oyster remains a public health concern and at least 3 days of depuration in clean sea water prior to consumption is recommended.

15.
Korean J Parasitol ; 53(1): 13-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25748704

RESUMO

Blastocystis sp. is a common zoonotic intestinal protozoa which has been classified into 17 subtypes (STs). A cross-sectional study was conducted to determine the prevalence and subtype distribution of Blastocystis in villagers living on the Thai-Myanmar border, where the risk of parasitic infection is high. A total of 207 stool samples were collected and DNA was extracted. PCR and sequencing using primers targeting small-subunit ribosomal RNA (SSU rRNA) gene were performed. The prevalence of Blastocystis infection was 37.2% (77/207). ST3 (19.8%; 41/207) was the predominant subtype, followed by ST1 (11.6%; 24/207), ST2 (5.3%; 11/207), and ST4 (0.5%; 1/207). A phylogenetic tree was reconstructed using the maximum likelihood (ML) method based on the Hasegawa-Kishino-Yano + G + I model. The percentage of bootstrapped trees in which the associated taxa clustered together was relatively high. Some sequences of Blastocystis positive samples (TK18, 39, 46, 71, and 90) were closely related to animals (pig and cattle) indicating zoonotic risks. Therefore, proper health education in parasitic prevention for the villagers should be promoted to improve their personal hygiene. Further longitudinal studies are required to monitor the prevalence of parasitic infections after providing health education and to investigate Blastocystis ST in animals living in these villages.


Assuntos
Infecções por Blastocystis/parasitologia , Blastocystis/classificação , Blastocystis/isolamento & purificação , Sorogrupo , Adulto , Idoso , Animais , Blastocystis/imunologia , Análise por Conglomerados , Estudos Transversais , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mianmar , Filogenia , RNA Ribossômico 18S/genética , População Rural , Análise de Sequência de DNA , Estudos Soroepidemiológicos , Tailândia , Adulto Jovem
16.
PLoS One ; 10(3): e0120997, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25822175

RESUMO

Naegleria fowleri is the causative agent of the fatal disease primary amebic meningoencephalitis. Detection of N. fowleri using conventional culture and biochemical-based assays is time-consuming and laborious, while molecular techniques, such as PCR, require laboratory skills and expensive equipment. We developed and evaluated a novel loop-mediated isothermal amplification (LAMP) assay targeting the virulence-related gene for N. fowleri. Time to results is about 90 min and amplification products were easily detected visually using hydroxy naphthol blue. The LAMP was highly specific after testing against related microorganisms and able to detect one trophozoite, as determined with spiked water and cerebrospinal fluid samples. The assay was then evaluated with a set of 80 water samples collected during the flooding crisis in Thailand in 2011, and 30 natural water samples from border areas of northern, eastern, western, and southern Thailand. N. fowleri was detected in 13 and 10 samples using LAMP and PCR, respectively, with a Kappa coefficient of 0.855. To the best of our knowledge, this is the first report of a LAMP assay for N. fowleri. Due to its simplicity, speed, and high sensitivity, the LAMP method described here might be useful for quickly detecting and diagnosing N. fowleri in water and clinical samples, particularly in resource-poor settings.


Assuntos
Naegleria fowleri/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Água/análise , Água/parasitologia , Sensibilidade e Especificidade , Tailândia , Virulência/genética , Água/química
17.
Parasite ; 21: 52, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25297887

RESUMO

Zoonotic Cryptosporidium spp., particularly C. meleagridis, C. canis, and C. felis, are enteric protozoa responsible for major public health concerns around the world. To determine the spread of this parasite in Thailand, we conducted molecular identification of Cryptosporidium spp. from animal samples around the country, by collecting and investigating the feces of seagulls (Chroicocephalus brunnicephalus and Chroicocephalus ridibundus), domestic pigeons (Columba livia domestica), dogs, and cats. Seagull and pigeon samples were collected at the seaside and on the riverside to evaluate their potential for waterborne transmission. Ten pigeon samples were combined into one set, and a total of seven sets were collected. Seventy seagull samples were combined into one set, and a total of 13 sets were collected. In addition, 111 dog samples were collected from cattle farms, and 95 dog and 80 cat samples were collected from a temple. We identified C. meleagridis in pigeons, Cryptosporidium avian genotype III in seagulls, C. canis in dogs, and C. felis in cats. In the temple, the prevalence was 2.1% (2/95) for dogs and 2.5% (2/80) for cats. No Cryptosporidium was found in dog samples from cattle farms. These are the first findings of C. meleagridis in domestic pigeons, and Cryptosporidium avian genotype III in seagulls. Our study invites further molecular epidemiological investigations of Cryptosporidium in these animals and their environment to evaluate the public health risk in Thailand.


Assuntos
Doenças das Aves/parasitologia , Doenças do Gato/parasitologia , Gatos/parasitologia , Charadriiformes/parasitologia , Columbidae/parasitologia , Criptosporidiose/parasitologia , Cryptosporidium/genética , Doenças do Cão/parasitologia , Cães/parasitologia , Criação de Animais Domésticos , Animais , Animais Domésticos/parasitologia , Animais Selvagens/parasitologia , Doenças das Aves/epidemiologia , Doenças do Gato/epidemiologia , Criptosporidiose/epidemiologia , Criptosporidiose/transmissão , Cryptosporidium/classificação , Cryptosporidium/isolamento & purificação , Reservatórios de Doenças/parasitologia , Doenças do Cão/epidemiologia , Fezes/parasitologia , Genótipo , Especificidade de Hospedeiro , RNA de Protozoário/genética , RNA Ribossômico/genética , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie , Tailândia/epidemiologia , Poluição da Água , Zoonoses
18.
Malar J ; 13: 3, 2014 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-24386898

RESUMO

BACKGROUND: Severe falciparum malaria (SM) remains a major cause of death in tropical countries. The reduced activity of ADAMTS13, increasing levels of ultra-large von Willebrand factor (ULVWF) in SM patients, are assumed as factors that intensify disease severity. However, the reason why ADAMTS13 activity is reduced in SM remains unclear. OBJECTIVES: To investigate whether rs4962153, febrile temperature, and microparticles, contribute to reduced ADAMTS13 activity. METHODS: Genotypic association of rs4962153 with ADAMTS13 antigen and activity was examined in 362 healthy Thai participants. The collagen binding assay was used to study the effects of febrile temperature and microparticles on ADAMTS13 activity. RESULTS: ADAMTS13 antigen and activity were decreased in participants with AA genotype, compared to AG and GG (antigen: p-value = 0.014, and < 0.001; activity: p-value = 0.036, and < 0.002, respectively). There was significantly reduced ADAMTS13 antigen in AG compared to GG (p-value = 0.013), but not in ADAMTS13 activity (p-value = 0.082). The number of rs4962153 A alleles correlated with the reduced level of antigen and activity (p-value <0.001 and p-value = 0.001, respectively). MPs showed an inhibitory effect on ADAMTS13 activity (p-value = 0.025). Finally, ADAMTS13 activity was decreased in a temperature and time-dependent manner. The interaction between these two factors was also observed (p-value <0.001). CONCLUSIONS: These findings suggest that the A allele of rs4962153, MPs, and febrile temperature, contribute to reduce ADAMTS13 activity in plasma. These data are useful in malaria or other diseases with reduced ADAMTS13 activity.


Assuntos
Proteínas ADAM/genética , Micropartículas Derivadas de Células/metabolismo , Febre/fisiopatologia , Malária Falciparum/genética , Polimorfismo de Nucleotídeo Único , Fator de von Willebrand/metabolismo , Proteínas ADAM/sangue , Proteína ADAMTS13 , Adolescente , Adulto , Ensaio de Imunoadsorção Enzimática , Feminino , Febre/parasitologia , Estudos de Associação Genética , Humanos , Malária Falciparum/parasitologia , Masculino , Plasmodium falciparum/fisiologia , Tailândia , Adulto Jovem
19.
Southeast Asian J Trop Med Public Health ; 45(6): 1252-63, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26466411

RESUMO

Intestinal parasitic infections can negatively impact growth and nutrition in children. The infections can induce oxidative stress, resulting in a variety of illnesses. We measured antioxidant enzyme levels in orphan children infected with intestinal parasites to investigate the influence of nutritional status on antioxidant enzymes. This cross sectional study was conducted at an orphanage in Thailand. Stool samples were obtained from each subject and examined for intestinal parasites. Anthropometric measurements, complete blood count and biochemical parameters, including serum superoxide dismutase (SOD) and glutathione peroxidase (GPx) levels, were obtained from studied subjects. One hundred twenty-eight children were included in the study. Intestinal parasites were found on microscopic examination of the stools in 36.7% (47/128); 18% (23/128) had a mixed parasite infection. Intestinal protozoa were found in 34.4% of subjects and intestinal helminthes were found in 2.3%. The median GPx level in children infected with intestinal parasites (2.3 ng/ml) was significantly lower than in non-infected children (7.7 ng/ml) (p < 0.05). However, there was no significant difference in SOD levels between the two groups. When comparing GPx levels in children with 1) pathogenic parasites, 2) non-pathogenic parasites and 3) no intestinal parasite infection, GPx levels differed significantly among three groups (2.2 ng/ml, 2.4 ng/ml and 7.7 ng/ml, respectively) (p < 0.05). When separating children by BMI and type of infection, the median SOD level in underweight children infected with pathogenic parasites (107.2 ng/ml) was significantly higher than in underweight children infected with non-pathogenic parasites (68.6 ng/ml) and without intestinal parasite infections (72.2 ng/ml). The present study identified two key findings: low GPx levels in children with intestinal parasitic infections, and the potential impact of malnutrition on some antioxidants.


Assuntos
Antioxidantes/análise , Crianças Órfãs , Enteropatias Parasitárias/enzimologia , Enteropatias Parasitárias/epidemiologia , Criança , Estudos de Coortes , Fezes/parasitologia , Humanos , Enteropatias Parasitárias/sangue , Tailândia/epidemiologia
20.
Trop Med Health ; 40(2): 31-5, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23097617

RESUMO

The majority of Giardia infections are transmitted by the fecal-oral route and cause giardiasis. Children who live in crowded conditions or low socio-economic areas are the risk group for Giardia infection. Interestingly, most of them are asymptomatic or only mildly infected and can shed the Giardia cysts in the environment. Thus, the diagnosis of Giardia infection in asymptomatic or mild infection plays an important role in achieving control of Giardia duodenalis transmission. The objective of this study was to examine parasitic infections using microscopy and to develop a real-time PCR method for detection of Giardia infection in the stool samples of children living on the Thai-Myanmar border. Both species-specific primers and fluorescent labeled G. duodenalis probe were designed using small-subunit ribosomal RNA (ssrRNA). The results showed that 10 (7.69%) and 40 (30.77%) of 130 stool samples were positive for G. duodenalis by microscopy and real-time PCR respectively. Only 3 out of 9 liquid stools revealed G. duodenalis positive using microscopy, but all of them were G. duodenalis-positive using real-time PCR. The detection limit of real-time PCR for G. duodenalis was 0.1 pg/25 µl reaction. It can detect both mild and asymptomatic Giardia infections in children living on the Thai-Myanmar border.

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