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1.
Malar J ; 17(1): 197, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29764451

RESUMO

BACKGROUND: In Thailand, artemisinin-based combination therapy (ACT) has been used to treat uncomplicated falciparum malaria since 1995. Unfortunately, artemisinin resistance has been reported from Thailand and other Southeast Asian countries since 2003. Malarone®, a combination of atovaquone-proguanil (ATQ-PG), has been used to cease artemisinin pressure in some areas along Thai-Cambodia border, as part of an artemisinin resistance containment project since 2009. This study aimed to determine genotypes and phenotypes of Plasmodium falciparum isolates collected from the Thai-Cambodia border after the artemisinin resistance containment project compared with those collected before. RESULTS: One hundred and nine of P. falciparum isolates collected from Thai-Cambodia border from Chanthaburi and Trat provinces during 1988-2016 were used in this study. Of these, 58 isolates were collected after the containment. These parasite isolates were characterized for in vitro antimalarial sensitivities including chloroquine (CQ), quinine (QN), mefloquine (MQ), piperaquine (PPQ), artesunate (AS), dihydroartemisinin (DHA), ATQ and PG and genetic markers for drug resistance including the Kelch13 (k13), Plasmodium falciparum chloroquine resistance transporter (pfcrt), P. falciparum multidrug resistance 1 (pfmdr1) and cytochrome b (cytb) genes. Mean CQ, QN, MQ, PPQ and AS IC50s of the parasite isolates collected from 2009 to 2016 exhibited significantly higher than those of parasites collected before 2009. Approximately 57% exhibited in vitro MQ resistance. Approximately 94% of the isolates collected from 2009 to 2016 contained the pfmdr1 184F allele. Mutations of the k13 gene were detected in approximately 90% of the parasites collected from 2009 to 2016 which were significantly higher than the parasite isolates collected before. No ATQ-resistant genotype and phenotype of P. falciparum were found among the isolates collected after the containment project. CONCLUSIONS: Although the containment project had been implemented in this area, the expansion of artemisinin-resistant parasites did not decline. In addition, reduced sensitivity of the partner drugs of ACT including MQ and PPQ were identified.


Assuntos
Antimaláricos/farmacologia , Artemisininas/farmacologia , Resistência a Medicamentos/genética , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/genética , Genótipo , Fenótipo , Plasmodium falciparum/fisiologia , Tailândia
2.
J Eukaryot Microbiol ; 64(6): 820-828, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28370779

RESUMO

Leishmania martiniquensis, a zoonotic hemoflagellate, is a causative agent of cutaneous (CL) and visceral leishmaniasis (VL) among humans and animals. This organism, first reported in Martinique Island, now has become an emerging infectious agent in Thailand. Symptomatic cases of L. martiniquensis infection among humans have continuously increased. In the meantime, asymptomatic infection of this novel species has seriously created national public health awareness and concern to prevent and control disease transmission. The unsuccessful serological test using the commercial rK39 dipstick based on antigen from Leishmania donovani to detect the antibodies against VL among infected Thai patients has encouraged us to further explore a new sensitive and specific antigenic epitope. In this study, we determined the sequences and expressed recombinant proteins of kinesin 39 (k39), heat shock protein 70 (hsp70), heat shock protein 83 (hsp83), and glycoprotein 63 (gp63) of L. martiniquensis to evaluate the diagnostic efficiency to detect antibodies against L. martiniquensis in patient sera. The preliminary results from western blot analysis have suggested that K39 is the most sensitive recombinant protein to detect L. martiniquensis. Moreover, this recombinant protein reacts with antibodies against L. donovani and Leishmania infantum, making it a promising antigen for further development of a universal rapid diagnostic tool for VL.


Assuntos
Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/imunologia , Western Blotting/métodos , Testes Diagnósticos de Rotina/métodos , Leishmaniose/diagnóstico , Proteínas Recombinantes/imunologia , Humanos , Sensibilidade e Especificidade , Tailândia
3.
Artigo em Inglês | MEDLINE | ID: mdl-27405118

RESUMO

Primaquine (PQ), an 8-aminoquinoline, is considered a tissue schizonticide drug for radical cure in vivax and ovale malaria, with minimal impact on asexual erythrocytic stages at therapeutic concentrations. Tafenoquine (TQ), a new 8-aminoquinoline analog of PQ, is active against both malaria parasite tissue and blood stages and is being promoted as a drug candidate for antimalarial chemotherapy and chemoprophylaxis and potential transmission blocking against Plasmodium vivax and P. falciparum. This study compared in vitro sensitivity of Thai P. falciparum isolates against three 8-aminoquinolines, PQ, TQ and sitamaquine (SQ), a related 8-aminoquinoline and assessed the importance of pfmdr1 polymorphism on the in vitro response. Seventy-eight laboratory adapted Thai P. falciparum isolates were evaluated for in vitro sensitivity to the three 8-aminoquinolines using a radioisotopic assay, and pfmdr1 polymorphisms were determined using PCR-based methods. All three drugs have weak antiplasmodial activity against asexual erythrocytic stage with SQ being the most potent by almost 10 folds. Cross susceptibility was observed in all three 8-aminoquinolines. Parasites containing pfmdr1 86Y, 184Y or 1034S allele exhibit significantly higher PQ IC50. TQ sensitivity was reduced in those parasites containing pfmdr1 86Y, 1034S or 1042N allele. However, there was no significant influence of pfmdr1 alleles on SQ sensitivity. The data highlight unique differences among three representative 8-aminoquinoline drugs that may be useful in understanding their potential utility in antimalarial development.


Assuntos
Aminoquinolinas/farmacologia , Antimaláricos/farmacologia , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Plasmodium falciparum , Primaquina/farmacologia , Humanos , Malária Falciparum/parasitologia , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/genética , Tailândia
4.
Parasitol Res ; 114(9): 3547-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26239798

RESUMO

Opisthorchis viverrini is highly prevalent throughout Southeast Asia. Chronic infection of this parasite leads to cholangiocarcinoma (CCA), a fatal bile duct cancer. The early and accurate detection of this parasite is very important; therefore, new PCR methods targeting cytochrome c oxidase subunit one and NADH dehydrogenase subunit one gene to detect O. viverrini in fecal specimens have been developed. Ninety O. viverrini-positive human fecal samples were used in this study. The PCR sensitivity of both genes was compared with internal transcribe spacer 2 (ITS2)-PCR. The sensitivity of cox1-PCR and nad1-PCR was 66.7 and 50 %, respectively. The sensitivity of cox1-PCR and nad1-PCR achieved 89.1 and 71.7 % in specimens containing O. viverrini eggs of >100 eggs per gram (EPG). Additionally, these primers can be used to provide the information on genetic diversity from mitochondrial genes of O. viverrini.


Assuntos
Neoplasias dos Ductos Biliares/etiologia , Colangiocarcinoma/etiologia , Complexo IV da Cadeia de Transporte de Elétrons/genética , NADH Desidrogenase/genética , Opistorquíase/diagnóstico , Opisthorchis/isolamento & purificação , Animais , Primers do DNA/genética , DNA de Helmintos/genética , DNA Mitocondrial/genética , DNA Espaçador Ribossômico/genética , Fezes/parasitologia , Proteínas de Helminto/genética , Humanos , Opistorquíase/complicações , Opistorquíase/parasitologia , Opisthorchis/genética , Reação em Cadeia da Polimerase , Tailândia
5.
J Med Assoc Thai ; 97 Suppl 2: S136-44, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25518187

RESUMO

BACKGROUND: Human Cytomegalovirus (HCMIV infects humans in all geographic areas. Polymorphisms ofglycoprotein B (gB) have been usedforgenotypic characterization of HCMV However information of gB genotyping of HCMV in Thailand is not clearly known especially in children. MATERIAL AND METHOD: A cross-sectional study was conducted to assess HCMV infection in 236 HIV seronegative and HIV seropositive children who attended an orphanage in Nonthaburi, Thailand by nested-PCR technique using urine specimens. HCMV gB genotypes were determined by restrictionfragment length polymorphism (RFLP), andDNA sequencing technique. RESULTS: Sixty-one percent (144/236) of the samples were HCMV positive, which consisted of 66.1% (37/56) of the HIV seropositive children and 59.4% (107/180) of the HIVsero-negative children. Multivariate analysis showed that children who living in one particular room were independently associated with HCMVinfection. Genotypic analysis revealed that the most prevalent genotype in these children was gB1; 85.4% (111/130) followed by gB3; 4.6% (6/130), gB2 and gB4 each at 2.3% (3/130). Mixed gB genotypes were identified in 5.4% (7/130) of the samples. CONCLUSION: HCMV infection, in particular gB1 genotype was commonly ident fled among these Thai orphans. Living in one particular room was associated with getting the infection. To prevent the transmission of HCMV infection in this setting, improvement in hygienic behavior ofchildcare workers should be focused.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Infecções por Citomegalovirus/epidemiologia , Citomegalovirus/genética , Infecções por HIV , Infecções Oportunistas Relacionadas com a AIDS/urina , Infecções Oportunistas Relacionadas com a AIDS/virologia , Criança , Crianças Órfãs/estatística & dados numéricos , Pré-Escolar , Estudos Transversais , Infecções por Citomegalovirus/urina , Infecções por Citomegalovirus/virologia , DNA Viral/análise , Demografia , Feminino , Genótipo , Humanos , Lactente , Recém-Nascido , Polimorfismo de Fragmento de Restrição , Prevalência , Tailândia/epidemiologia , Proteínas do Envelope Viral/análise
6.
J Med Assoc Thai ; 97 Suppl 2: S52-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25518176

RESUMO

BACKGROUND: Blastocystis infection is one of the most common intestinal protozoan infections reported in Thai population of all age groups for which epidemiological information is important to understand patterns of transmission for developing methods ofprevention and control for each specific group. The authors aimed to study prevalence, incidence and riskfactors associated with Blastocystis infection in orphans and childcare workers. Additionally, subtypes ofBlastocystis were identified MATERIAL AND METHOD: A retrospective cohort study of Blastocystis sp. was conducted in orphans aged less than 5 years and their childcare workers at Babies' Home, Nonthaburi Province, Thailand. A base line survey was conducted in December 2009 and afollow-up survey was conducted in April 2010. A total of 336 and 331 stool samples were collected. Blastocystis infection was examined using short-term in vitro cultivation in Jones's medium supplemented with 10% fetal calf serum. To analyze subtypes ofBlastocystis sp., PCR-RFLP of the small subunit ribosomal RNA gene was performed. RESULTS: Theprevalence ofBlastocystis infection in December 2009 and April 2010 were 8.1% and 13.3%, respectively The inlcidence rate ofBlastocystis infection was 1.6/100 person-months. Subtype analysis ofBlastocystis sp. in December 2009 and in April 2010 showed that subtype 3 was the most predominant (76% and 76%), followed by subtype 1 (16% and 20%), and unidentified subtype (8% and 4%), respectively. Subtype 3 is of human origin, thus person-to-person transmission is considered a major route ofBlastocystis infection in this population. CONCLUSION: Person-to-person transmission of Blastocystis infection in orphans living in the same house had been proposed, thus the prevalence and incidence of Blastocystis infection could be used to reflect the hygienic condition in the orphanage. Infection prevention and control practice can be effectively implemented.


Assuntos
Infecções por Blastocystis/epidemiologia , Adolescente , Blastocystis/genética , Blastocystis/isolamento & purificação , Infecções por Blastocystis/parasitologia , Infecções por Blastocystis/transmissão , Criança , Crianças Órfãs/estatística & dados numéricos , Pré-Escolar , Estudos de Coortes , Transmissão de Doença Infecciosa , Fezes/parasitologia , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Orfanatos , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Prevalência , Estudos Retrospectivos , Fatores de Risco , Tailândia/epidemiologia
7.
Acta Trop ; 249: 107081, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37993039

RESUMO

Leishmaniasis is an emerging infectious disease in Thailand, with Leishmania martiniquensis and Leishmania orientalis identified as the primary causative agents among immunocompetent and immunocompromised individuals. Variations in drug susceptibility among different Leishmania species have been reported in different regions. Therefore, drug susceptibility assays are essential to assess the effectiveness of antileishmanial drugs used or potentially used in the affected areas. This study investigated the in vitro drug sensitivity of L. martiniquensis and L. orientalis, along with two reference species causing VL, namely L. donovani and L. infantum, against six antileishmanial drugs. Using a parasite-rescue and transformation assay, the results demonstrated that the IC50 values of amphotericin B (AmB), miltefosine (MIL), and sodium stibogluconate (Sb(III)) against all Leishmania species tested were within the sensitive range of each drug. On the contrary, the IC50 values of artemisinin (ART) and dihydroartemisinin (DHA), drugs primarily used for malaria treatment, were outside the sensitive range of the Leishmania species tested except L. infantum. This in vitro study highlights that AmB could effectively exhibit good sensitivity against the intracellular amastigotes of L. martiniquensis and L. orientalis. Also, MIL and Sb(III) could be considered alternative drugs for antileishmanial treatment in Thailand.


Assuntos
Antiprotozoários , Leishmania , Leishmaniose , Parasitos , Humanos , Animais , Leishmaniose/tratamento farmacológico , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Anfotericina B/farmacologia , Anfotericina B/uso terapêutico
8.
BMC Microbiol ; 13: 60, 2013 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-23506297

RESUMO

BACKGROUND: Visceral leishmaniasis (VL) caused by Leishmania siamensis is an emerging disease continuously reported in six southern provinces of Thailand. To date, the phylogenetic relationships among Leishmania isolates from Thai patients and other Leishmania species are still unclear and the taxonomic diversity needs to be established. In this study, the phylogenetic inference trees were constructed based on four genetic loci (i.e., SSU-rRNA, ITS1, hsp70, and cyt b), using DNA sequences obtained from autochthonous VL patients from southern Thailand and reference sequences of reported Leishmania isolates from other studies deposited in GenBank. RESULTS: Phylogenetic analyses of hsp70 and cyt b loci supported a clade comprised of L. siamensis isolates, which is independent to the other members in the genus Leishmania. In combination with genetic distance analysis, sequence polymorphisms were observed among L. siamensis isolates and two different lineages could be differentiated, lineages PG and TR. Phylogenetic analysis of the cyt b gene further showed that L. siamensis lineage TR is closely related to L. enrietti, a parasite of guinea pigs. CONCLUSION: The finding of this study sheds further light on the relationships of L. siamensis, both in intra- and inter-species aspects. This information would be useful for further in-depth studies on the biological properties of this important parasite.


Assuntos
DNA de Protozoário/genética , Leishmania/classificação , Leishmania/genética , Leishmaniose Visceral/parasitologia , Análise por Conglomerados , DNA de Protozoário/química , Humanos , Leishmania/isolamento & purificação , Dados de Sequência Molecular , Tipagem de Sequências Multilocus , Filogenia , Tailândia
9.
BMC Infect Dis ; 13: 333, 2013 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-23870062

RESUMO

BACKGROUND: Leishmaniasis, caused by Leishmania siamensis, is an emerging disease in Thailand. Although reported cases have been increasing, epidemiological information of the disease including host and vector aspects is not clearly known. This study was a preliminary survey of the potential vector of L. siamensis in an affected area of leishmaniasis, Trang Province, southern Thailand. METHODS: The collection of sandflies was performed around the area where a case of leishmaniasis was reported using CDC light traps. Species of sandfly were identified based on morphological characteristics according to Lewis's key. PCR amplification and sequencing of the heat shock protein 70 gene (hsp70) was used to identify L. siamensis DNA in sandflies. RESULTS: A total of 146 male and female sandflies were collected in the affected areas. Of 71 female sandflies, four species were identified, i.e., Sergentomyia (Neophlebotomus) gemmea, S. (Neophlebotomus) iyengari, S. (Parrotomyia) barraudi and Phlebotomus (Anaphlebotomus) stantoni. Among these species, S. (Neophlebotomus) gemmea was the most predominant species in all areas. DNA of L. siamensis was identified in S. (Neophlebotomus) gemmea. Nucleotide sequences of PCR products using DNA extracted from S. (Neophlebotomus) gemmea showed 99.8% identity to L. siamensis. CONCLUSION: S. (Neophlebotomus) gemmea might be a potential vector of L. siamensis in an affected area, Trang Province, southern Thailand. However further studies are needed to prove whether these sandflies can be natural vectors of leishmaniasis.


Assuntos
Doenças Transmissíveis Emergentes/parasitologia , Insetos Vetores/parasitologia , Leishmania/isolamento & purificação , Leishmaniose/parasitologia , Psychodidae/parasitologia , Animais , Doenças Transmissíveis Emergentes/transmissão , DNA de Protozoário/análise , DNA de Protozoário/genética , Feminino , Leishmania/genética , Leishmaniose/transmissão , Masculino , Reação em Cadeia da Polimerase , Tailândia
10.
Southeast Asian J Trop Med Public Health ; 44(4): 636-40, 2013 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-24050097

RESUMO

We conducted a survey of human cytomegalovirus (HCMV) genotypes among 176 children aged 1 month to 5 years living at Phayathai Babies' Home in Nonthaburi Province, Thailand to determine the prevalence of HCMV glycoprotein B (gB) genotype. The study was conducted on urine samples using nested polymerase chain reaction and restriction fragment length polymorphism; the HCMV gB1 genotype was found in 89% of subjects, much higher than previous reports. Our results show a high proportion of HCMV gB1 infected children in this population.


Assuntos
Infecções por Citomegalovirus/epidemiologia , Citomegalovirus/genética , Orfanatos/estatística & dados numéricos , Proteínas do Envelope Viral/genética , Pré-Escolar , Infecções por Citomegalovirus/genética , DNA Viral/genética , Feminino , Genótipo , Humanos , Lactente , Masculino , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Prevalência , Tailândia
11.
Malar J ; 11: 7, 2012 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-22221394

RESUMO

BACKGROUND: The emergence of Plasmodium falciparum resistance to most currently used anti-malarial drugs is a major problem in malaria control along the Thai-Myanmar and Thai-Cambodia borders. Quinine (QN) with tetracycline/doxycycline has been used as the second-line treatment for uncomplicated falciparum malaria. In addition, QN monotherapy has been the first-line treatment for falciparum malaria in pregnant women. However, reduced in vitro and in vivo responses to QN have been reported. To date, a few genetic markers for QN resistance have been proposed including Plasmodium falciparum chloroquine resistance transporter (pfcrt), P. falciparum multidrug resistance 1 (pfmdr1), and P. falciparum Na+/H+ exchanger (pfnhe-1). This study was to investigate the role of the pfmdr1 and pfnhe-1 gene on in vitro QN sensitivity in Thai isolates of P. falciparum. METHODS: Eighty-five Thai isolates of P. falciparum from the Thai-Myanmar and Thai-Cambodia borders from 2003-2008 were determined for in vitro QN sensitivity using radioisotopic assay. Polymorphisms of the pfmdr1 and pfnhe-1 gene were determined by PCR-RFLP and sequence analysis. Associations between the in vitro QN sensitivity and the polymorphisms of the pfmdr1 and pfnhe-1 gene were evaluated. RESULTS: The mean QN IC50 was 202.8 nM (range 25.7-654.4 nM). Only four isolates were QN resistant when the IC50 of >500 nM was used as the cut-off point. Significant associations were found between the pfmdr1 mutations at codons N86Y and N1042D and in vitro QN sensitivity. However, no associations with the number of DNNND, DDNNNDNHNDD, and NHNDNHNNDDD repeats in the microsatellite ms4760 of the pfnhe-1 gene were identified. CONCLUSION: Data from the present study put doubt regarding the pfnhe-1 gene as to whether it could be used as the suitable marker for QN resistance in Thailand. In contrast, it confirms the influence of the pfmdr1 gene on in vitro QN sensitivity.


Assuntos
Antimaláricos/farmacologia , Malária Falciparum/parasitologia , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Plasmodium falciparum/efeitos dos fármacos , Quinina/farmacologia , Trocadores de Sódio-Hidrogênio/genética , Camboja , DNA de Protozoário/genética , Feminino , Humanos , Concentração Inibidora 50 , Mianmar , Testes de Sensibilidade Parasitária/métodos , Plasmodium falciparum/genética , Plasmodium falciparum/isolamento & purificação , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Polimorfismo de Nucleotídeo Único , Gravidez , Tailândia
12.
BMC Microbiol ; 11: 206, 2011 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-21933419

RESUMO

BACKGROUND: The glutamate dehydrogenase gene (gdh) is one of the most popular and useful genetic markers for the genotypic analysis of Giardia duodenalis (syn. G. lamblia, G. intestinalis), the protozoan that widely causes enteric disease in humans. To determine the distribution of genotypes of G. duodenalis in Thai populations and to investigate the extent of sequence variation at this locus, 42 fecal samples were collected from 3 regions of Thailand i.e., Central, Northern, and Eastern regions. All specimens were analyzed using PCR-based genotyping and recombinant subcloning methods. RESULTS: The results showed that the prevalence of assemblages A and B among these populations was approximately equal, 20 (47.6%) and 22 (52.4%), respectively. Sequence analysis revealed that the nucleotide diversity of assemblage B was significantly greater than that in assemblage A. Among all assemblage B positive specimens, the allelic sequence divergence within isolates was detected. Nine isolates showed mixed alleles, ranged from three to nine distinct alleles per isolate. Statistical analysis demonstrated the occurrence of genetic recombination within subassemblages BIII and BIV was likely. CONCLUSION: This study supports increasing evidence that G. duodenalis has the potential for genetic exchange.


Assuntos
Coinfecção/parasitologia , Variação Genética , Giardia lamblia/enzimologia , Giardia lamblia/genética , Giardíase/parasitologia , Glutamato Desidrogenase/genética , Recombinação Genética , Alelos , Pré-Escolar , Fezes/parasitologia , Feminino , Giardia lamblia/classificação , Giardia lamblia/isolamento & purificação , Glutamato Desidrogenase/metabolismo , Humanos , Lactente , Masculino , Dados de Sequência Molecular , Filogenia , Tailândia
13.
Artigo em Inglês | MEDLINE | ID: mdl-22299458

RESUMO

Small subunit ribosomal DNA (SSU-rDNA), glutamate dehydrogenase (gdh), beta-giardin, triosephosphate isomerase (tpi), and elongation factor 1-alpha (ef1-alpha) genes are useful genetic markers for genotypic analysis of the intestinal protozoan, Giardia duodenalis (syn. G. lamblia, G. intestinalis), the cause of enteric disease in humans. To quantitatively compare the discriminatory power of these loci, 43 fecal samples were collected from central, northern and eastern Thailand and G. duodenalis specimens were analyzed using PCR-based genotyping and subcloning methods. Approximately equal prevalence of assemblage A (21) and B (22) were present among these populations. Analysis of Simpson's index and Wallace coefficient values from assemblage B isolates together with the data obtained from GenBank showed that the combination of two loci provides a higher discrimination power for subgenotyping G. duodenalis than using any single locus.


Assuntos
Giardia lamblia/genética , Giardíase/parasitologia , DNA de Protozoário/genética , Bases de Dados de Ácidos Nucleicos , Fezes/parasitologia , Genes de Protozoários , Marcadores Genéticos , Genótipo , Humanos , Tipagem de Sequências Multilocus , Reação em Cadeia da Polimerase , Tailândia
14.
J Clin Microbiol ; 48(9): 3165-8, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20631108

RESUMO

A multiplex PCR assay for the simultaneous detection of Mycobacterium tuberculosis and Pneumocystis jirovecii was developed using IS6110-based detection for M. tuberculosis and mitochondrial large-subunit (mtLSU) rRNA gene detection for P. jirovecii. Ninety-five pulmonary blinded samples were examined using the developed multiplex PCR assay, and the results were compared with those obtained by the single nested PCRs targeting IS6110 for M. tuberculosis and mtLSU rRNA for P. jirovecii. Of the 95 pulmonary samples tested, the multiplex nested PCR developed here could detect 36 cases of M. tuberculosis infection, 35 cases of P. jirovecii infection, and 17 cases of M. tuberculosis and P. jirovecii coinfections. The sensitivities of the multiplex nested PCR in detecting M. tuberculosis and P. jirovecii were 92.1% and 81.4%, respectively, whereas the specificities in detecting M. tuberculosis and P. jirovecii were 98.2% and 100%, respectively.


Assuntos
Técnicas de Laboratório Clínico/métodos , Técnicas de Diagnóstico Molecular/métodos , Mycobacterium tuberculosis/isolamento & purificação , Infecções por Pneumocystis/diagnóstico , Pneumocystis carinii/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Tuberculose/diagnóstico , Elementos de DNA Transponíveis/genética , DNA Bacteriano/genética , DNA Fúngico/genética , DNA Mitocondrial/genética , DNA Ribossômico/genética , Humanos , Mycobacterium tuberculosis/genética , Infecções por Pneumocystis/microbiologia , Pneumocystis carinii/genética , Sensibilidade e Especificidade , Tuberculose/microbiologia
15.
Exp Parasitol ; 124(3): 357-9, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19961851

RESUMO

This study describes a simple technique for releasing miracidia from Opisthorchis-like eggs before DNA extraction by keeping PBS washed specimens at 4 degrees C for two days. Using PCR amplification, the sensitivity of the PBS incubation technique was as good as that obtained from freeze-thaw technique. Moreover, this low-cost technique is less laborious.


Assuntos
DNA de Helmintos/isolamento & purificação , Fezes/parasitologia , Opisthorchis/fisiologia , Animais , Temperatura Baixa , Humanos , Opisthorchis/genética , Opisthorchis/isolamento & purificação , Óvulo/fisiologia , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , Cloreto de Sódio , Fatores de Tempo
16.
Artigo em Inglês | MEDLINE | ID: mdl-20578509

RESUMO

A modified set of primers was developed to increase the sensitivity of nested PCR amplification of glutamate dehydrogenase (gdh) gene to detect and genotype Giardia duodenalis cysts in stool specimens. This modified set of primers had a significantly higher sensitivity (82%) than that of a previously published PCR primer set (53%).


Assuntos
Giardia lamblia/genética , Glutamato Desidrogenase/genética , Reação em Cadeia da Polimerase/métodos , Primers do DNA , Fezes/parasitologia , Genótipo , Humanos , Sensibilidade e Especificidade , Tailândia
17.
Am J Trop Med Hyg ; 103(4): 1502-1509, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32700674

RESUMO

There are two main species of Leishmania reported in Thailand, that is, Leishmania siamensis and Leishmania martiniquensis. Moreover, leishmaniasis cases caused by Leishmania donovani complex were also reported. There is still a lack of information concerning risk factors of Leishmania infection in Thailand. This study aimed to identify the risk factors of Leishmania infection caused by these three species among HIV-infected patients. A cross-sectional study was conducted in HIV clinic at Trang Hospital, Thailand. Nested PCR and sequencing were performed to detect Leishmania DNA in blood and saliva samples and identify Leishmania species. A standardized questionnaire was used to interview individuals. A total of 526 patients were recruited in this study. Sixty-three (12.0%) were positive for L. siamensis, 24 (4.6%) were positive for L. martiniquensis, and 23 (4.4%) were positive for L. donovani complex. Risk factors of L. siamensis infection included using intravenous drug (adjusted odds ratio [AOR] 2.01, 95% CI: 1.01-4.02). Risk factors of L. martiniquensis infection included female gender (AOR 4.23, 95% CI: 1.52-11.75), using recreational drug (AOR 3.43, 95% CI: 1.00-11.74), and having comorbidities (AOR 4.94, 95% CI: 2.00-12.21). Risk factors of L. donovani complex infection included having opportunistic infection (AOR 4.22, 95% CI: 1.00-17.79), CD4 count 200-500 cells/mm3 (AOR 3.64, 95% CI: 1.14-6.86), and not using insect repellent (AOR 3.04, 95% CI: 1.08-8.58). This study identified the risk factors of Leishmania infection caused by three Leishmania species in Thailand. The data could be useful for disease prevention and control. Further studies on trends of Leishmania infection and preventive measures are recommended.


Assuntos
Infecções por HIV/epidemiologia , Leishmania/isolamento & purificação , Leishmaniose/epidemiologia , Adulto , Contagem de Linfócito CD4 , Estudos Transversais , Feminino , Humanos , Leishmania/genética , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prevalência , Fatores de Risco , Saliva/parasitologia , Tailândia/epidemiologia
18.
Am J Trop Med Hyg ; 102(4): 838-843, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32043456

RESUMO

Human liver fluke infection caused by Opisthorchis viverrini increases the risk of cholangiocarcinoma (CCA) reported along the Mekong basin including Thailand, Lao People's Democratic Republic (PDR), Cambodia, and Vietnam. The highest incidence of CCA has been reported in northeastern Thailand where liver fluke infection is prevalent. This study aimed to investigate the prevalence of O. viverrini infection in a northeastern-descendent community in rural Sa Kaeo Province, eastern Thailand, using stool examination and molecular technique. The Kato-Katz method was performed to determine eggs per gram (EPG) for infection intensity. Phosphate-buffered saline-ethyl acetate concentration was used to prepare specimens for polymerase chain reaction (PCR) and restriction fragment length polymorphism of the internal transcribed spacer 2 (ITS2) region of the ribosomal RNA. From 1,245 specimens, 105 (8.4%) samples were identified as Opisthorchis-like eggs from stool examination, and all positive specimens indicated light infection (< 1,000 EPG). From positive Opisthorchis-like egg samples, 55.2% (58/105) were identified as O. viverrini eggs from ITS2-PCR assay for which low infection intensity might result in a negative PCR result (44.8%). Using multiple logistic regression analysis, males were at 3.1 times higher risk of acquiring O. viverrini infection than females. From phylogenetic analysis, in eastern Thailand, nucleotide sequences of O. viverrini were grouped as a monoclade as those isolated from Greater Mekong, Vietnam, Myanmar, and west Siberia. The results revealed that the surveyed community is a low-grade endemic area of O. viverrini infection. Thus, data from this study can be used to improve health-promoting programs and activities to control the infection and its subsequent CCA.


Assuntos
Opistorquíase/epidemiologia , Opisthorchis/isolamento & purificação , Adulto , Idoso , Animais , Fezes/parasitologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Opistorquíase/diagnóstico , Opisthorchis/genética , Contagem de Ovos de Parasitas , Filogenia , Prevalência , Fatores de Risco , Tailândia , Adulto Jovem
19.
J Clin Microbiol ; 47(11): 3739-41, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19710259

RESUMO

This study was performed to evaluate the incidence of and risk factors for Enterocytozoon bieneusi carriage in an orphanage in Bangkok, Thailand. E. bieneusi has been identified by PCR every 2 consecutive months since June 2003. The incidence ranged between 0.6 and 4.7/100 person-months. Person-to-person transmission was indicated by risk factor analysis and genotyping information.


Assuntos
Portador Sadio/epidemiologia , Portador Sadio/microbiologia , Enterocytozoon/isolamento & purificação , Microsporidiose/epidemiologia , Microsporidiose/microbiologia , Portador Sadio/transmissão , Pré-Escolar , Transmissão de Doença Infecciosa , Enterocytozoon/classificação , Enterocytozoon/genética , Feminino , Genótipo , Infecções por HIV/complicações , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Microsporidiose/transmissão , Orfanatos , Reação em Cadeia da Polimerase/métodos , Prevalência , Fatores de Risco , Tailândia/epidemiologia
20.
Planta Med ; 75(8): 839-42, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19288406

RESUMO

The root extract of Trichosanthes cucumerina L. and bryonolic acid (1), its main constituent, as well as the fruit juice and cucurbitacin B (3), its main constituent, were tested for cytotoxicity against four human breast cancer cell lines (SKBR3, MCF7, T47D, and MDA-MB435), two lung cancer cell lines (A549 and SK-LU1), and one colon cancer cell line (Caco-2). The root extract had higher IC (50) values than bryonolic acid (1) against three breast cancer cell lines (MCF7 = 267/121, T47D = 316/124, MDA-MB435 = 140/90 microL/mL) and one lung cancer cell line (A549 = 106/100 microL/mL). The fruit juice also had higher IC (50) values than cucurbitacin B (3) against the four breast cancer cell lines (131/73, 375/35, 249/60, and 156/26 microL/mL, respectively) and one lung cancer cell line (141/41 microL/mL) as shown above, as well as against the colon cancer cell line (101/1.5 microL/mL). However, the root extract inhibited SK-LU1 more strongly than did the fruit juice, cucurbitacin B (3), and bryonolic acid (1) (149/169/180/>500 microL/mL, respectively). The root extract inhibited the two lung and three breast cancer cell lines (SKBR3, MDA-MB435, and MCF7) more strongly than the fruit juice. Bryonolic acid (1) inhibited MDA-MB435 somewhat better than the other tested human cancer cell lines. The fruit juice inhibited the colon cancer cell line (Caco-2) more strongly than the root extract. Cucurbitacin (3) inhibited human cancer cell lines, especially Caco-2, much more strongly than bryonolic acid (1). In addition to bryonolic acid (1), bryononic acid (2), cucurbitacin B (3), and dihydrocucurbitacin B (4) also were isolated from the root extract.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias do Colo/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Trichosanthes/química , Triterpenos/uso terapêutico , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Células CACO-2/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Frutas , Humanos , Concentração Inibidora 50 , Fitoterapia , Preparações de Plantas/isolamento & purificação , Preparações de Plantas/farmacologia , Preparações de Plantas/uso terapêutico , Raízes de Plantas , Triterpenos/isolamento & purificação , Triterpenos/farmacologia
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