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1.
BMJ Paediatr Open ; 8(1)2024 02 26.
Article de Anglais | MEDLINE | ID: mdl-38413125

RÉSUMÉ

Paediatric sepsis prevalence data from low-income and middle-income countries are lacking. In a cross-sectional study, we assessed clinician recognition and documentation of non-neonatal community-acquired paediatric sepsis in two rural border provinces in Thailand among children admitted between October and December 2017. Of the 152 children meeting sepsis criteria (26.9 paediatric sepsis patients per 1000 admissions), 15 (9.9%) had a clinician-documented admission diagnosis of sepsis or septic shock and 18 (11.8%) had a discharge diagnosis with International Classification of Diseases-10 codes related to sepsis. Clinician underdocumentation may cause challenges in global paediatric sepsis surveillance.


Sujet(s)
Sepsie , Humains , Enfant , Thaïlande/épidémiologie , Études transversales , Sepsie/diagnostic , Sepsie/épidémiologie , Hôpitaux , Classification internationale des maladies
2.
Antibiotics (Basel) ; 11(11)2022 Nov 19.
Article de Anglais | MEDLINE | ID: mdl-36421303

RÉSUMÉ

Shigellosis is a leading global cause of diarrheal disease and travelers' diarrhea now being complicated by the dissemination of antibiotic resistance, necessitating the development of alternative antibacterials such as therapeutic bacteriophages (phages). Phages with lytic activity against Shigella strains were isolated from sewage. The genomes of 32 phages were sequenced, and based on genomic comparisons belong to seven taxonomic genera: Teetrevirus, Teseptimavirus, Kayfunavirus, Tequatrovirus, Mooglevirus, Mosigvirus and Hanrivervirus. Phage host ranges were determined with a diverse panel of 95 clinical isolates of Shigella from Southeast Asia and other geographic regions, representing different species and serotypes. Three-phage mixtures were designed, with one possessing lytic activity against 89% of the strain panel. This cocktail exhibited lytic activity against 100% of S. sonnei isolates, 97.2% of S. flexneri (multiple serotypes) and 100% of S. dysenteriae serotypes 1 and 2. Another 3-phage cocktail composed of two myophages and one podophage showed both a broad host range and the ability to completely sterilize liquid culture of a model virulent strain S. flexneri 2457T. In a Galleria mellonella model of lethal infection with S. flexneri 2457T, this 3-phage cocktail provided a significant increase in survival.

3.
Mil Med ; 2022 Feb 04.
Article de Anglais | MEDLINE | ID: mdl-35134989

RÉSUMÉ

INTRODUCTION: We established a murine wound infection model with doxycycline treatment against multidrug-resistant Acinetobacter baumannii (AB5075) in Institute of Cancer Research (ICR) outbred mice. METHODS: Using three groups of neutropenic ICR mice, two full-thickness dorsal dermal wounds (6 mm diameter) were made on each mouse. In two groups, wounds were inoculated with 7.0 × 104 colony-forming units of AB5075. Of these two groups, one received a 6-day regimen of doxycycline while the other was sham treated with phosphate-buffered saline as placebo control. Another uninfected/untreated group served as a control. Wound closure, clinical symptoms, bacterial burden in wound beds and organs, and wound histology were investigated. RESULTS: Doxycycline-treated wounds completely healed by day 21, but untreated, infected wounds failed to heal. Compared to controls, wound infections without treatment resulted in significant reductions in body weight and higher bacterial loads in wound beds, lung, liver, and spleen by day 7. Histological evaluation of wounds on day 21 revealed ulcerated epidermis, muscle necrosis, and bacterial presence in untreated wounds, while wounds treated with doxycycline presented intact epidermis. CONCLUSIONS: Compared to the previously developed BALB/c dermal wound model, this study demonstrates that the mouse strain selected impacts wound severity and resolution. Furthermore, this mouse model accommodates two dorsal wounds rather than only one. These variations offer investigators increased versatility when designing future studies of wound infection. In conclusion, ICR mice are a viable option as a model of dermal wound infection. They accommodate two simultaneous dorsal wounds, and upon infection, these wounds follow a different pattern of resolution compared to BALB/c mice.

4.
Mil Med ; 2022 Jan 05.
Article de Anglais | MEDLINE | ID: mdl-34986242

RÉSUMÉ

INTRODUCTION: The effective dual antibiotics ceftriaxone (CRO) and azithromycin (AZM) have successfully treated Neisseria gonorrhoeae (GC) infection, however, the CRO- and AZM-resistant strains have been sporadically detected globally and in Thailand. Furthermore, there are no currently antimicrobial susceptibility profiles of the GC isolates obtained from soldiers reported in Thailand. Hence, this is the first study to describe the antimicrobial susceptibility profiles of GC isolates obtained from predominately soldiers who seeking care at Military Camp Hospitals, in Thailand from 2014 to 2020. MATERIALS AND METHODS: A total of 624 symptomatic gonococcal samples were received from 10 military hospitals during 2014-2020. They were collected from urethral swabs and inoculated into selective media. The suspected GC isolates were subcultured and presumptively identified using conventional microbiology techniques. Antimicrobial susceptibility test was performed by Etest to determine minimal inhibitory concentration (µg/mL) against AZM, benzylpenicillin, cefepime, cefixime, ceftriaxone (CRO), ciprofloxacin, spectinomycin, and tetracycline using the criteria outlined in the Clinical and Laboratory Standards Institute guidelines. This study was approved by Institutional Review Board, Royal Thai Army Medical Department under protocol number S036b/56 and Walter Reed Army Institute of Research, and Silver Spring, MD under protocol number WR #2039. RESULTS: A total of 624 samples were collected from symptomatic gonococcal infectious patients with 91.5% (571/624) of samples obtained from soldiers. Of those, 78% (488/624) were identified as GC and 92% (449/488) of them were isolated from soldiers. All GC samples collected were susceptible to CRO (first-line treatment) with only one GC isolate identified as non-susceptible to cefepime and three isolates identified as non-susceptible to AZM. CONCLUSION: The recommended dual treatment of GC infections with CRO and AZM is currently an effective empirical treatment for patients who are seeking care at military hospitals in Thailand. Nevertheless, cefepime is a fourth-generation cephalosporin with documented high activity against GC strains equal to other "third-generation" cephalosporins such as CRO. Due to the active duty of military personnel, they concerned about the confidentiality and frequently seek treatment at civilian clinics. Additionally, due to the availability of antibiotics over the counter in Thailand, many choose the option to self-medicate without a physician's prescription. These could be subsequently driven the gradual increase of multidrug-resistant gonococcal strains throughout the country. Thus, the GC surveillance would be needed for further Force Health Protection and public health authorities in response to the drug-resistant GC threats.

5.
Microb Drug Resist ; 28(1): 102-105, 2022 Jan.
Article de Anglais | MEDLINE | ID: mdl-34242096

RÉSUMÉ

This study describes the first finding of Salmonella enterica serotype Choleraesuis (Salmonella Choleraesuis) isolate harboring mobile colistin resistance (mcr)-3.1 obtained from human blood sample. The clinical relevant blood sample was collected during October 2018. The phenotypic identification and antimicrobial susceptibility testing (AST) were studied by using automate microbiology platform (Phoenix M50, BD), and in-depth characterization by whole genome sequencing. The phenotypic identification was reported Salmonella Choleraesuis. AST result demonstrated that this isolate had high minimum inhibitory concentrations (MICs) against colistin, fluoroquinolone, and cephalosporin III and IV, which are first-line antibiotic treatment choices for Gram-negative bacterial pathogen infections. This Salmonella Choleraesuis is harboring mcr-3.1 and presented a diversity carbapenemase including blaTEM and blactx-m-55. Regarding the multilocus sequence typing result, this Salmonella presented ST139 that related to the Choleraesuis variant sensu stricto. Swine is not the host specific for the Salmonella Choleraesuis since it also causes enteric and other diseases in human. Hence, the presence of the mobile plasmid colistin mcr-3.1 resistant gene in human sample is resulting to the public health concerns due to the fact that it is enable to transmit to other hosts and distribute into an environment.


Sujet(s)
Antibactériens/pharmacologie , Colistine/pharmacologie , Multirésistance bactérienne aux médicaments/génétique , Salmonella/effets des médicaments et des substances chimiques , Salmonella/génétique , Gènes bactériens , Humains , Mâle , Tests de sensibilité microbienne , Adulte d'âge moyen , Phénotype , Sérogroupe , Thaïlande
6.
Antimicrob Agents Chemother ; 65(11): e0067121, 2021 10 18.
Article de Anglais | MEDLINE | ID: mdl-34398671

RÉSUMÉ

Information on causative diarrheal pathogens and their associated antimicrobial susceptibility remains limited for Cambodia. This study describes antimicrobial resistance patterns for Shigella and nontyphoidal Salmonella isolates collected in Cambodia over a 5-year period. Multidrug resistance was shown in 98% of Shigella isolates, with 70%, 11%, and 29% of isolates being resistant to fluoroquinolones, azithromycin, and cephalosporin, respectively. As many as 11% of Shigella isolates were resistant to nearly all oral and parenteral drugs typically used for shigellosis, demonstrating extreme drug resistance phenotypes. Although a vast majority of nontyphoidal Salmonella isolates remained susceptible to cephalosporins (99%) and macrolides (98%), decreased susceptibility to ciprofloxacin was found in 67% of isolates, which is notably higher than previous reports. In conclusion, increasing antimicrobial resistance of Shigella and nontyphoidal Salmonella is a major concern for selecting empirical treatment of acute infectious diarrhea in Cambodia. Treatment practices should be updated and follow local antimicrobial resistance data for the identified pathogens.


Sujet(s)
Shigella , Antibactériens/pharmacologie , Antibactériens/usage thérapeutique , Cambodge , Diarrhée/traitement médicamenteux , Résistance microbienne aux médicaments , Humains , Tests de sensibilité microbienne , Salmonella
7.
PLoS One ; 16(2): e0246598, 2021.
Article de Anglais | MEDLINE | ID: mdl-33544770

RÉSUMÉ

Arcobacter butzleri is an emerging zoonotic food-borne and water-borne pathogen that can cause diarrhea in humans. The global prevalence of A. butzleri infection is underestimated, and little is known about their phenotypic and genotypic characterization. The aim of this study was to determine antimicrobial susceptibility (AST) profiles, detect related virulence genes, and classify sequence type (ST) of A. butzleri isolates obtained from human stool and food samples. A total of 84 A. butzleri isolates were obtained from human diarrheal (n = 25), non-diarrheal (n = 24) stool, and food (n = 35) samples in Thailand. They were evaluated for phenotypic identification by conventional microbiological procedures and AST by Kirby-Bauer disc diffusion method as well as virulence genes detection. Representative isolates from each origin were selected based on the presence of virulence genes and AST profiles to analyze genetic diversity by multilocus sequence typing (MLST). All isolates showed resistance to nalidixic acid 40.5% (34/84), ciprofloxacin 11.9% (10/84), azithromycin 8.3% (7/84), and erythromycin 3.6% (3/84). Regarding the ten virulence genes detected, cj1349, mviN and pldA had the highest prevalence 100% (84/84), followed by tlyA 98.8% (83/84), cadF 97.6% (82/84), ciaB 71.4% (60/84), hecA and hecB 22.6% (19/84), iroE 15.5% (13/84) and irgA 10.7% (9/84), respectively. Three virulence genes were present among A. butzleri isolates of human diarrheal stool and food samples, with a significant difference observed among isolates; hecB [36% (9/25) and 8.6% (3/35)], hecA [36% (9/25) and 5.7% (2/35)], and irgA [24% (6/25) and 2.9% (1/35)] (p < 0.05), respectively. The hecA and hecB virulence genes functions are related to the mechanism of hemolysis, while irgA supports a bacterial nutritional requirement. MLST analysis of 26 A. butzleri isolates revealed that 16 novel STs exhibited high genetic diversity. The results of this study is useful for understanding potentially pathogenic and antimicrobial-resistant A. butzleri in Thailand. The pathogenic virulence markers hecB, hecA, and irgA have the potential to be developed for rapid diagnostic detection in human diarrheal stool. No significant relationships among STs and sources of origin were observed. Little is known about A. butzleri, the mechanism of action of these virulence genes, is a topic that needs further investigation.


Sujet(s)
Arcobacter/classification , Arcobacter/isolement et purification , Diarrhée/microbiologie , Infections bactériennes à Gram négatif/microbiologie , Animaux , Arcobacter/génétique , Arcobacter/pathogénicité , Diarrhée/anatomopathologie , Gènes bactériens , Génotype , Infections bactériennes à Gram négatif/épidémiologie , Infections bactériennes à Gram négatif/métabolisme , Infections bactériennes à Gram négatif/anatomopathologie , Humains , Typage par séquençage multilocus/méthodes , Thaïlande/épidémiologie , Facteurs de virulence/génétique
8.
Gut Pathog ; 12: 17, 2020.
Article de Anglais | MEDLINE | ID: mdl-32308742

RÉSUMÉ

BACKGROUND: Diarrhea remains a major public health problem for both civilian and military populations. This study describes the prevalence of acute diarrheal illness etiological agents, their antibiotic resistance distribution patterns, the resulting impact upon military force health protection, and potential prevention and treatment strategies. RESULTS: Forty-eight acute diarrhea stool samples from US military personnel deployed to Thailand from 2013-2017 were screened for enteric pathogens using ELISA, the TaqMan Array Card (TAC), and conventional microbiological methods. These isolates were also evaluated using antimicrobial susceptibility testing (AST) against ampicillin (AMP), azithromycin (AZM), ceftriaxone (CRO), ciprofloxacin (CIP), nalidixic acid (NA), erythromycin (ERY), and trimethoprim-sulfamethoxazole (SXT) using commercial methodology. Susceptibility results were interpreted following the CLSI and NARM guidelines. Questionnaire data obtained from 47/48 volunteers indicated that 89.4% (42/47) reported eating local food and the most common clinical symptoms were nausea and abdominal pain (51%; 24/47). Multiple bacterial species were identified from the 48 stool samples with diarrhea etiological agents being detected in 79% (38/48) of the samples distributed as follows: 43.8% (21/48) Campylobacter jejuni and Campylobacter species, 42% (20/48) diarrheagenic Escherichia coli, and 23% (11/48) Salmonella. Co-infections were detected in 46% (22/48) of the samples. All C. jejuni isolates were resistant to CIP and NA. One C. jejuni isolate exhibited resistance to both AZM and ERY. Lastly, an association between exposure to poultry and subsequent detection of the diarrhea-associated pathogens E. coli and P. shigelloides was significant (p < 0.05). CONCLUSION: The detection of Campylobacter isolates with CIP, AZM and ERY resistance has critical force health protection and public health implications, as these data should guide effective Campylobacteriosis treatment options for deployed military members and travelers to Southeast Asia. Additional research efforts are recommended to determine the association of pathogen co-infections and/or other contributing factors towards diarrheal disease in military and traveler populations. Ongoing surveillance and AST profiling of potential disease-causing bacteria is required for effective disease prevention efforts and treatment strategies.

9.
Gut Pathog ; 11: 19, 2019.
Article de Anglais | MEDLINE | ID: mdl-31080519

RÉSUMÉ

Campylobacter is the most common cause of traveler's diarrhea (TD) and human bacterial gastroenteritis. A heteroresistant Campylobacter jejuni (C. jejuni) isolate, identified by microbiological methods and characterized with molecular techniques, was obtained from a traveler in Nepal suffering TD. The presence of atypical colonies within the clear zone of inhibition was the first evidence of an atypical phenotype, leading to additional characterization of this heteroresistant strain. Antimicrobial susceptibility testing (AST) and population analysis profiling (PAP) demonstrated heteroresistance to azithromycin (AZM), a first-line antibiotic treatment for Campylobacter infections. Molecular analysis indicated a point mutation occurred on the 23S rRNA gene at the A2075G transitions, and the number of mutated gene copies was proportional to AZM resistance. Heteroresistant C. jejuni subpopulations from acute TD are likely underestimated, which may lead to treatment failures, as was the case for this patient. The presence of a heteroresistant strain in a high antibiotic environment may select for additional drug resistance and enable distribution into hospital and local communities.

10.
Sci Rep ; 8(1): 11736, 2018 08 06.
Article de Anglais | MEDLINE | ID: mdl-30082843

RÉSUMÉ

Hawaii has one of the highest incidences of Campylobacteriosis in the United States, but there remains little published data on circulating strains or antimicrobial resistance. We characterized 110 clinical Campylobacter isolates (106 C. jejuni, 4 C. coli) processed at Tripler Army Medical Center in Honolulu, HI from 2012-2016. Twenty-five percent of C. jejuni isolates exhibited fluoroquinolone (FQ) resistance, compared with 16% for tetracycline (TET), and 0% for macrolides. Two of the four C. coli isolates were resistant to FQ, TET, and macrolides. C. jejuni isolates further underwent multilocus sequence typing, pulsed-field gel electrophoresis, and molecular capsular typing. Nineteen capsule types were observed, with two capsule types (HS2 and HS9) being associated with FQ resistance (p < 0.001 and p = 0.006, respectively). HS2 FQ-resistant isolates associated with clonal complex 21, possibly indicating clonal spread in FQ resistance. Macrolides should be considered for treatment of suspect cases due to lack of observed resistance.


Sujet(s)
Campylobacter/effets des médicaments et des substances chimiques , Adulte , Antibactériens/pharmacologie , Campylobacter/génétique , Infections à Campylobacter/prévention et contrôle , Résistance bactérienne aux médicaments/génétique , Électrophorèse en champ pulsé , Femelle , Fluoroquinolones/pharmacologie , Hawaï , Humains , Macrolides/pharmacologie , Mâle , Typage par séquençage multilocus , Études rétrospectives , Tétracycline/pharmacologie , Jeune adulte
11.
Gut Pathog ; 10: 18, 2018.
Article de Anglais | MEDLINE | ID: mdl-29854008

RÉSUMÉ

Helicobacter fennelliae (H. fennelliae) is associated with human gastroenteritis; however, H. fennelliae was isolated and confirmed by phenotypic and genotypic identification from a non-diarrheal child stool sample in Cambodia. Antimicrobial susceptibility testing demonstrated that this isolate had a high minimal inhibitory concentration against macrolides and quinolones, which are first-line antibiotic treatment choices for Campylobacter infections. Consequently, macrolides and quinolones were likewise expected to be ineffective against Campylobacter-like organisms such as H. fennelliae. This isolate warranted further genetic characterization to better understand associated antibiotic resistance mechanisms. Resistant pathogens from asymptomatic diarrheal cases are likely underestimated, and as such colonized individuals may spread resistant organisms to local community members and the environment.

12.
Clin Infect Dis ; 67(1): 120-127, 2018 06 18.
Article de Anglais | MEDLINE | ID: mdl-29351583

RÉSUMÉ

Background: Travelers' diarrhea (TD) is a common illness experienced by travelers from developed countries who visit developing countries. Recent questionnaire-based surveillance studies showed that approximately 6%-16% of travelers experienced TD while visiting Thailand; however, a majority of TD information was limited mainly to US military populations. Methods: A TD surveillance study was conducted at Bumrungrad International Hospital in 2012-2014 in Bangkok, Thailand. Enteropathogens were identified using conventional methods and the TaqMan® array card (TAC), which uses real-time polymerase chain reaction for the simultaneous detection of multiple pathogens. Analyses to determine pathogen-disease and symptoms association were performed to elucidate the clinical relevance of each enteropathogen. Results: TAC identified more pathogens per sample than conventional methods. Campylobacter spp. were the most prevalent, followed by the diarrheagenic Escherichia coli and norovirus GII. These agents had significant pathogen-disease associations as well as high attributable fractions among diarrheal cases. A wide range of pathogen loads for Campylobacter spp. was associated with TD, while heat-labile toxin enterotoxigenic Escherichia coli was associated with an increased pathogen load. Most cases were associated with inflammatory diarrhea, while Campylobacter spp. and Shigella spp. were associated with dysentery. Conclusions: A pan-molecular diagnostic method such as TAC produces quantifiable and comparable results of all tested pathogens, thereby reducing the variability associated with multiple conventional methods. This allows better determination of the clinical relevance of each diarrhea etiologic agent, as well as their geographical relevance in Thailand.


Sujet(s)
Diarrhée/diagnostic , Réaction de polymérisation en chaine en temps réel , Maladie liée aux voyages , Adolescent , Adulte , Sujet âgé , Infections bactériennes/diagnostic , Infections bactériennes/épidémiologie , Campylobacter/isolement et purification , Diarrhée/épidémiologie , Escherichia coli entérotoxigène/isolement et purification , Escherichia coli/isolement et purification , Femelle , Humains , Surveillance immunologique , Mâle , Adulte d'âge moyen , Norovirus/isolement et purification , Séquençage par oligonucléotides en batterie , Thaïlande/épidémiologie , Voyage , Maladies virales/diagnostic , Maladies virales/épidémiologie , Jeune adulte
13.
Emerg Infect Dis ; 22(9): 1640-3, 2016 09.
Article de Anglais | MEDLINE | ID: mdl-27532684

RÉSUMÉ

We observed multidrug resistance in 10 (91%) of 11 Shigella isolates from a diarrheal surveillance study in Cambodia. One isolate was resistant to fluoroquinolones and cephalosporins and showed decreased susceptibility to azithromycin. We found mutations in gyrA, parC, ß-lactamase, and mphA genes. Multidrug resistance increases concern about shigellosis treatment options.


Sujet(s)
Antibactériens/pharmacologie , Diarrhée/épidémiologie , Diarrhée/microbiologie , Multirésistance bactérienne aux médicaments , Dysenterie bacillaire/épidémiologie , Dysenterie bacillaire/microbiologie , Shigella/effets des médicaments et des substances chimiques , Adolescent , Adulte , Antibactériens/usage thérapeutique , Cambodge/épidémiologie , Enfant d'âge préscolaire , Diarrhée/traitement médicamenteux , Diarrhée/histoire , Dysenterie bacillaire/traitement médicamenteux , Dysenterie bacillaire/histoire , Femelle , Gènes bactériens , Histoire du 21ème siècle , Humains , Nourrisson , Mâle , Tests de sensibilité microbienne , Adulte d'âge moyen , Mutation , Surveillance de la population , Shigella/génétique , Jeune adulte
14.
Vector Borne Zoonotic Dis ; 15(9): 539-44, 2015 Sep.
Article de Anglais | MEDLINE | ID: mdl-26378973

RÉSUMÉ

Currently, no vaccine has been developed to protect humans from naturally acquired heterologous Orientia tsutsugamushi infections. To enhance the validity of vaccine candidates, we are developing a murine chigger challenge model with the O. tsutsugamushi Lc-1-infected Leptotrombidium chiangraiensis Line-1. To this end, an intraperitoneal (i.p.) murine challenge model using an O. tsutsugamushi Lc-1 isolate was developed for eventual validation of the chigger challenge model. We have determined that the murine lethal dose that kills 50% of the challenged mice (MuLD50) of a liver/spleen homogenate developed from O. tsutsugamushi Lc-1-infected ICR Swiss mice to be 10(-6.9). Employing different inoculum doses of this homogenate, the bacterial load using quantitative real-time PCR (qPCR) was determined to range from 60 to 1.6 × 10(5) genome equivalent copies (GEC)/µL of liver and 33.4 to 2.2 × 10(5) GEC/µL of spleen tissue. The clinical outcomes relative to homogenate dose levels followed a dose-dependent pattern. The successful development and characterization of the O. tsutsugamushi Lc-1 i.p. challenge model will assist in the development and validation of a mouse chigger challenge scrub typhus model.


Sujet(s)
Orientia tsutsugamushi/physiologie , Fièvre fluviale du Japon/microbiologie , Trombiculidae/microbiologie , Animaux , Charge bactérienne , Modèles animaux de maladie humaine , Femelle , Humains , Injections péritoneales , Dose létale 50 , Foie/microbiologie , Souris , Souris de lignée ICR , Orientia tsutsugamushi/génétique , Rate/microbiologie
15.
J Med Entomol ; 51(3): 658-60, 2014 May.
Article de Anglais | MEDLINE | ID: mdl-24897859

RÉSUMÉ

Orientia tsutsugamushi is a pathogen transmitted by Leptotrombidium that causes scrub typhus. To develop an infection mouse model, a mite-derived isolate of O. tsutsugamushi was established from a laboratory-maintained colony of Leptotrombidium chiangraiensis (O. tsutsugamushi Lc-1). This Lc-1 isolate was initially presented to ICR (CD-1) mice by feeding an infected Lc chigger on the ear of a mouse. Once the Lc-1 was adapted to the ICR mice, quantitative real-time polymerase chain reaction was used to investigate O. tsutsugamushi genomic equivalent copies in tissues and sera. Furthermore, times to onset of the signs of infection are reported in this study. This study provides information useful for future research on this host-pathogen interaction and the associated vaccine efficacy trials.


Sujet(s)
Orientia tsutsugamushi/physiologie , Fièvre fluviale du Japon/microbiologie , Trombiculidae/microbiologie , Animaux , Modèles animaux de maladie humaine , Foie/microbiologie , Souris , Souris de lignée ICR , Réaction de polymérisation en chaine en temps réel , Rate/microbiologie
16.
ISRN Dent ; 2013: 362750, 2013.
Article de Anglais | MEDLINE | ID: mdl-23762572

RÉSUMÉ

Background. Oral lichen planus (OLP) is a common chronic inflammatory immune-mediated disease, with an etiopathogenesis associated with cell-mediated immunological dysfunction. Viral infection has been hypothesized as a predisposing factor in the pathogenesis of this disease. Viruses may alter host cell function by inducing the abnormal expression of cellular proteins leading to disease development. However, reports on the relationship between human papillomavirus (HPV) and OLP are inconclusive. Objective. To explore the association between HPV and OLP in Thai patients. Materials and Methods. DNA was extracted from thirty-seven fresh-frozen tissue biopsy specimens from OLP lesions, and polymerase chain reaction assay for the L1 and E1 genes covering 32 types of high- and low-risk HPV was performed. Results. HPV DNA was detected in one tissue biopsy from an atrophic-type OLP lesion. All control samples were negative. Genomic sequencing of the E1 gene PCR product demonstrated that the HPV-type 16 found in the lesion is closely related to the East Asian type. Conclusion. Our data indicate a low prevalence of HPV infection in OLP lesions in Thai patients.

17.
Exp Appl Acarol ; 58(1): 23-34, 2012 Sep.
Article de Anglais | MEDLINE | ID: mdl-22527840

RÉSUMÉ

Rodents are the natural hosts for Leptotrombidium mites that transmit Orientia tsutsugamushi, the causative agent of scrub typhus, a potentially fatal febrile human disease. Utilizing mite lines that included O. tsutsugamushi infected and non-infected Leptotrombidium species we investigated the varied infection response of outbred mice (ICR) exposed to L. chiangraiensis (Lc), L. imphalum (Li) and L. deliense (Ld). Each of six mite lines (Lc1, Lc5, Li3, Li4, Li7 and Ld) was separately placed in the inner ears of ICR mice either as a single individual (individual feeding, IF) or as a group of 2-4 individuals (pool feeding, PF). The species of infected chigger feeding on mice significantly affected mortality rates of the mice, with mite lines of Lc causing higher mean (±SE) mortality (90.7 ± 3.6 %) than mite lines of Li (62.9 ± 5.6 %) or Ld (53.6 ± 5.8 %). Mouse responses which included time to death, food consumption and total mice weight change depended on mite species and their O. tsutsugamushi genotype, more than on feeding procedure (IF vs. PF) except for mite lines within the Lc. Infected mite lines of Lc were the most virulent infected mites assessed whereas the infected Ld species was the least virulent for the ICR. Mice killed by various mite lines showed enlarged spleens and produced ascites. The results of this investigation of the clinical responses of ICR mice to feeding by various infected mite lines indicated that the different species of infected mites and their O. tsutsugamushi genotype produced different clinical presentations in ICR mice, a scrub typhus mouse model which mimics the natural transmission of O. tsutsugamushi that is critical for understanding scrub typhus disease in terms of natural transmission, host-pathogen-vector interaction and vaccine development.


Sujet(s)
Mites (acariens)/parasitologie , Orientia tsutsugamushi/physiologie , Fièvre fluviale du Japon/microbiologie , Animaux , Femelle , Souris , Souris de lignée ICR , Fièvre fluviale du Japon/transmission
18.
New Microbiol ; 34(2): 147-56, 2011 Apr.
Article de Anglais | MEDLINE | ID: mdl-21617826

RÉSUMÉ

Cervical cytological data may not be sufficient for cervical cancer screening and prevention. In this project, we determined HPV genotype among infected Thai women with different cytological findings by characterization of E1 genes. Five hundred and thirty-five specimens were tested by PCR amplification of the E1 genes. HPV genotypes were determined by sequencing, comparison with the GenBank database and were analyzed in relation to different cytological findings. HPV-DNA by PCR were typed and revealed 32 different genotypes. HR-HPV (HPV16, 18 or 52) was detected in all samples with cervical cancer cytology. HPV16 was most prevalent irrespective of cervical cytology. Moreover, HPV31 and 52 were most prevalent in the HSIL and LSIL groups whereas HPV66 was found mostly in the LSIL group. The LSIL group displayed the highest variation of HPV genotypes. Moreover, HPV31 and 52 predominated in the HSIL and LSIL groups especially HPV52 which was found in cancer samples. We hoped that these data of HPV genotypes can be used as preliminary data of HPV in Thailand and can serve as basic data for future research into the HPV genotype in south-east Asia.


Sujet(s)
Alphapapillomavirus/génétique , Alphapapillomavirus/isolement et purification , Protéines des oncogènes viraux/génétique , Infections à papillomavirus/virologie , Alphapapillomavirus/classification , Cytodiagnostic , Femelle , Génotype , Humains , Données de séquences moléculaires , Infections à papillomavirus/diagnostic , Réaction de polymérisation en chaîne , Thaïlande , Frottis vaginaux
19.
Asian Pac J Cancer Prev ; 11(1): 117-22, 2010.
Article de Anglais | MEDLINE | ID: mdl-20593940

RÉSUMÉ

One of the most common cancers in women worldwide is cervical cancer, with death rates highest in less developed countries, including Thailand. This study was conducted to explore the prevalence of human papillomavirus (HPV) and its related cytological abnormalities among women attending cervical screening clinics in Thailand using the polymerase chain reaction (PCR). LBC specimens (ThinPrep, Hologic, West Sussex, UK) were subjected to PCR of the E1 region to identify the most prevalent HPV types. Information on age and cytology grade was also collected. Among a total of 1,662 women, 29 different HPV types were found and the overall HPV prevalence was 8.7%. HPV prevalence among the general population amounted to 7.8%. The following HPV types were identified: HPV16 (17.9%), HPV90 (16.6%) and HPV71 (10.3%). The rates of other types were as follows; HPV66 (6.9%), HPV52 (6.2%), HPV34 (5.5%), HPV31 (5.3%), HPV42 (4.8%) and HPV39 (3.4%). HPV infection peaked in women aged around 20-39 years and thereafter gradually declined. As expected, HPV DNA can be found in normal cytology specimens. These results which elucidate HPV distribution in Thailand could be useful for vaccine development and the national cervical cancer prevention program.


Sujet(s)
Papillomaviridae/génétique , Infections à papillomavirus/génétique , Tumeurs du col de l'utérus/génétique , Adulte , Sujet âgé , Études cas-témoins , Col de l'utérus/virologie , ADN viral/génétique , Femelle , Génotype , Humains , Adulte d'âge moyen , Stadification tumorale , Infections à papillomavirus/épidémiologie , Infections à papillomavirus/virologie , Réaction de polymérisation en chaîne , Prévalence , Pronostic , Thaïlande/épidémiologie , Tumeurs du col de l'utérus/épidémiologie , Tumeurs du col de l'utérus/virologie , Frottis vaginaux , Jeune adulte
20.
Intervirology ; 53(3): 161-6, 2010.
Article de Anglais | MEDLINE | ID: mdl-20068350

RÉSUMÉ

OBJECTIVE: The aim of this study was to attain molecular knowledge of human papillomavirus type 18 (HPV18) by sequencing the whole genome of HPV18 isolated from Thai women at various clinical stages of disease progression. METHOD: Our group analyzed 9 samples of whole-genome HPV18 in infected women ranging from normal to cervical cancer by PCR, a sequencing method and bioinformatics programs. RESULTS: Phylogenetic analysis based on the whole genome showed that HPV18 samples were more closely related to the European and Asian-American type than the African type. The vaccine strain's L1 nucleotide (US patent 5820870) showed a close relationship to the African type. However, our data cannot indicate the correlation between cytological data and nucleotide or amino acid variation. CONCLUSION: Our group cannot draw any inference between the clinical stage of disease progression and amino acid alterations as there were only 1 or 2 samples available for each clinical trial. However, we hope that these new data on the HPV genome, which are representative of the entire genome of HPV in Southeast Asia, can serve as basis data for future research on the pathogenesis of cervical cancer. Additionally, the second-generation HPV18 vaccines should be tested on both HPV18-L1 and HPV18-L2 for increasing potential protection.


Sujet(s)
Génome viral , Papillomavirus humain de type 18/génétique , Papillomavirus humain de type 18/isolement et purification , Infections à papillomavirus/anatomopathologie , Infections à papillomavirus/virologie , Adulte , Sujet âgé , Analyse de regroupements , ADN viral/composition chimique , ADN viral/génétique , Femelle , Papillomavirus humain de type 18/classification , Humains , Adulte d'âge moyen , Données de séquences moléculaires , Phylogenèse , Analyse de séquence d'ADN , Similitude de séquences , Indice de gravité de la maladie , Thaïlande , Jeune adulte
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