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1.
Microbiol Spectr ; : e0428923, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38786200

RESUMEN

Most people infected with Mycobacterium tuberculosis (Mtb) are believed to be in a state of latent tuberculosis (TB) infection (LTBI). Although LTBI is asymptomatic and not infectious, there is a risk of developing active disease even decades after infection. Here, to characterize mutations acquired during LTBI, we collected and analyzed Mtb genomes from seven Japanese patient pairs, each pair consisting of two active TB patients whose starting dates of developing active disease were >3 years apart; one had a high suspicion of LTBI before developing active disease, whereas the other did not. Thereafter, we compared these genomes with those of longitudinal sample pairs within a host of chronic active TB infections combined with public data. The bacterial populations in patients with LTBI were genetically more homogeneous and accumulated single nucleotide polymorphisms (SNPs) slower than those from active disease. Moreover, the lower proportion of nonsynonymous SNPs indicated weaker selective pressures during LTBI than active disease. Finally, the different mutation spectrums indicated different mutators between LTBI and active disease. These results suggest that the likelihood of the acquisition of mutations responsible for antibiotic resistance and increased virulence was lower in the Mtb population from LTBI than active disease.IMPORTANCEControlling latent tuberculosis (TB) infection (LTBI) activation is an effective strategy for TB elimination, where understanding Mycobacterium tuberculosis (Mtb) dynamics within the host plays an important role. Previous studies on chronic active disease reported that Mtb accumulated genomic mutations within the host, possibly resulting in acquired drug resistance and increased virulence. However, several reports suggest that fewer mutations accumulate during LTBI than during the active disease, but the associated risk is largely unknown. Here, we analyzed the genomic dynamics of Mtb within the host during LTBI. Our results statistically suggest that Mtb accumulates mutations during LTBI, but most mutations are under low selective pressures, which induce mutations responsible for drug resistance and virulence. Thus, we propose that LTBI acts as a source for new TB disease rather than as a period for in-host genome evolution.

2.
Shokuhin Eiseigaku Zasshi ; 64(4): 136-144, 2023.
Artículo en Japonés | MEDLINE | ID: mdl-37673603

RESUMEN

In order to quickly analyze 8 types of nonvolatile amine, such as histamine, a simple analytical method was developed. A test solution was prepared only by diluting and filtering a trichloroacetic acid extract before analysis via LC-MS/MS.As a result of the additive recovery test with 11 types of food, including fresh seafood, seafood processed products, and other processed foods, all amines had an accuracy in the range of 70 to 120% with a repeatability of less than 15% RSD in 9 types of food. This confirmed the validity of the analytical method with the lower limit of quantification between 5 to 6 mg/kg.


Asunto(s)
Aminas , Espectrometría de Masas en Tándem , Cromatografía Liquida , Histamina , Alimentos Procesados
3.
Infect Genet Evol ; 114: 105495, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37652282

RESUMEN

Currently, tuberculosis (TB) in Japan is highly prevalent among elderly patients who were born during a time when TB was highly prevalent. Mycobacterium tuberculosis (Mtb) lineage 2 (L2) is the predominant strain in the country. Moreover, the proportion of foreign-born patients with TB has been increasing. This epidemiological situation in Japan motivated us to explore the heterogeneity in transmission dynamics among the sublineages of Mtb L2 within this aging population. For this purpose, we conducted a population-based whole genome sequencing analysis of 550 Mtb strains in Kobe, Japan, and employed pairwise single nucleotide polymorphism (SNP) distance clustering and terminal branch length (TBL) distribution analysis to assess Mtb transmission. The genomic clustering rate with a threshold of ≤5 SNPs was significantly lower in elderly patients aged 70 years or higher than in non-elderly patients. The elderly patient group showed significantly longer TBL than the non-elderly group. These results supported the notion that reactivation of distant infection is a major driving force for the high incidence of TB in elderly individuals. The age group distribution and frequency of lineages/sublineages were found to significantly differ between foreign-born and Japan-born patients. The increased proportion of foreign-born patients might have resulted in more strain diversity in Japan. The L2.2.A sublineage demonstrated a significant association with elderly patients and exhibited lower transmission rates, which indicate to be prone to reactivate from long-term latency. In contrast, L2.2.Modern, showed a strong association with younger and foreign-born patients. This sublineage showed a high genomic cluster rate, suggesting its high transmissibility. The other three major sublineages, namely L2.2.AA2, L2.2.AA3.1, and L2.2.AA3.2, exhibited a consistent increase in cluster rates across varying SNP thresholds, indicating their relatively recent emergence as endemic sublineages in Japan. In conclusion, this study highlights distinct differences in the transmission dynamics of L2 sublineages within an aging society.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Anciano , Humanos , Persona de Mediana Edad , Mycobacterium tuberculosis/genética , Japón/epidemiología , Genotipo , Tuberculosis/epidemiología , Tuberculosis/microbiología , Epidemiología Molecular
4.
One Health ; 16: 100559, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37363238

RESUMEN

Mycobacterium avium subsp. hominissuis (MAH) is one of the most prevalent mycobacteria causing non-tuberculous mycobacterial disease in humans and animals. Of note, MAH is a major cause of mycobacterial granulomatous mesenteric lymphadenitis outbreaks in pig populations. To determine the precise source of infection of MAH in a pig farm and to clarify the epidemiological relationship among pig, human and environmental MAH lineages, we collected 50 MAH isolates from pigs reared in Japan and determined draft genome sequences of 30 isolates. A variable number of tandem repeat analysis revealed that most pig MAH isolates in Japan were closely related to North American, European and Russian human isolates but not to those from East Asian human and their residential environments. Historical recombination analysis revealed that most pig isolates could be classified into SC2/4 and SC3, which contain MAH isolated from pig, European human and environmental isolates. Half of the isolates in SC2/4 had many recombination events with MAH lineages isolated from humans in East Asia. To our surprise, four isolates belonged to a new lineage (SC5) in the global MAH population. Members of SC5 had few footprints of inter-lineage recombination in the genome, and carried 80 unique genes, most of which were located on lineage specific-genomic islands. Using unique genetic features, we were able to trace the putative transmission route via their host pigs. Together, we clarify the possibility of species-specificity of MAH in addition to local adaptation. Our results highlight two transmission routes of MAH, one exposure on pig farms from the environment and the other via pig movement. Moreover, our study also warns that the evolution of MAH in pigs is influenced by MAH from patients and their residential environments, even if the MAH are genetically distinct.

5.
J Infect Chemother ; 29(3): 289-293, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36494058

RESUMEN

OBJECTIVES: The emergence of the Alpha variant of novel coronavirus 2019 (SARS-CoV-2) is a concerning issue but their clinical implications have not been investigated fully. METHODS: We conducted a nested case-control study to compare severity and mortality caused by the Alpha variant (B.1.1.7) with the one caused by the wild type as a control from December 2020 to March 2021, using whole-genome sequencing. 28-day mortality and other clinically important outcomes were evaluated. RESULTS: Infections caused by the Alpha variant were associated with an increase in the use of oxygen (43.4% vs 26.3%. p = 0.017), high flow nasal cannula (21.2% vs 4.0%, p = 0.0007), mechanical ventilation (16.2% vs 6.1%, p = 0.049), ICU care (30.3% vs 14.1%, p = 0.01) and the length of hospital stay (17 vs 10 days, p = 0.031). More patients with the Alpha variant received medications such as dexamethasone. However, the duration of each modality did not differ between the 2 groups. Likewise, there was no difference in 28-day mortality between the 2 groups (12% vs 8%, p = 0.48), even after multiple sensitivity analyses, including propensity score analysis. CONCLUSION: The Alpha variant was associated with a severe form of COVID-19, compared with the non-Alpha wild type, but might not be associated with higher mortality.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2/genética , Estudios de Casos y Controles , Japón/epidemiología
6.
Front Microbiol ; 13: 892447, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35756040

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of the current coronavirus disease 2019 (COVID-19) pandemic and associated respiratory infections, has been detected in the feces of patients. Therefore, determining SARS-CoV-2 RNA levels in sewage may help to predict the number of infected people within the area. In this study, we quantified SARS-CoV-2 RNA copy number using reverse transcription quantitative real-time PCR with primers and probes targeting the N gene, which allows the detection of both wild-type and variant strain of SARS-CoV-2 in sewage samples from two wastewater treatment plants (WWTPs) in Kobe City, Japan, during the fourth and fifth pandemic waves of COVID-19 between February 2021 and October 2021. The wastewater samples were concentrated via centrifugation, yielding a pelleted solid fraction and a supernatant, which was subjected to polyethylene glycol (PEG) precipitation. The SARS-CoV-2 RNA was significantly and frequently detected in the solid fraction than in the PEG-precipitated fraction. In addition, the copy number in the solid fraction was highly correlated with the number of COVID-19 cases in the WWTP basin (WWTP-A: r = 0.8205, p < 0.001; WWTP-B: r = 0.8482, p < 0.001). The limit of capturing COVID-19 cases per 100,000 people was 0.75 cases in WWTP-A and 1.20 cases in WWTP-B, respectively. Quantitative studies of RNA in sewage can be useful for administrative purposes related to public health, including issuing warnings and implementing preventive measures within sewage basins.

7.
Jpn J Infect Dis ; 75(6): 604-607, 2022 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-35768276

RESUMEN

Hepatitis E virus (HEV) is the causative agent of viral hepatitis E. In Japan, HEV genotype 3 (G3) and G4 are predominantly detected, while G1, mainly imported from countries in continental Asia, is rare. In the present study, we detected a G1 HEV strain in a patient who visited Japan from India. When PLC/PRF/5 cells (subclone 4-21) were inoculated with a stool suspension from this patient, accumulation of HEV RNA was observed in the spent culture medium, indicating that HEV had been successfully isolated from this specimen. A nearly complete HEV genome was obtained by RT-PCR amplification. Phylogenetic analyses revealed that the newly isolated HEV strain, designated 9HE36c, belongs to subtype 1g of HEV G1.


Asunto(s)
Virus de la Hepatitis E , Hepatitis E , Humanos , Virus de la Hepatitis E/genética , Filogenia , Japón , Genotipo , ARN Viral/genética , ARN Viral/análisis
8.
Jpn J Infect Dis ; 75(3): 249-253, 2022 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-34588370

RESUMEN

A rapid and simple alternative test to real-time reverse transcription-polymerase chain reaction (RT-PCR) is required for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to help curb the spread of coronavirus disease (COVID-19). In the present study, we compared the RT-PCR method with chemiluminescent enzyme immunoassay (CLEIA) and reverse transcription loop-mediated isothermal amplification (RT-LAMP). We observed that the number of SARS-CoV-2 RNA copies and the CLEIA antigen quantification values were highly correlated. The detection limit for antigen quantification was 42.8 RNA copies for saliva samples and 23.4 copies for nasopharyngeal swab samples. For both purified RNA and purification-free crude RNA, the number of RNA copies and RT-LAMP threshold time (Tt) values were inversely correlated. RT-LAMP with purified RNA detected low copy numbers of RNA (5-50 copies), whereas fewer than 250 RNA copies could not be detected using crude RNA. CLEIA antigen quantification is potentially useful for large-scale screening, as it is compatible with high-throughput testing. RT-LAMP with crude RNA samples is applicable for rapid point-of-care testing because it can directly use patient specimens. It is important to select a diagnostic method that is simple and rapid when compared with RT-PCR, depending on the situation.


Asunto(s)
COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , Humanos , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , ARN Viral/análisis , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , SARS-CoV-2/genética , Sensibilidad y Especificidad
10.
GigaByte ; 2021: gigabyte33, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-36824340

RESUMEN

Mycobacterium avium subsp. hominissuis (MAH) is one of the most important agents causing non-tuberculosis mycobacterial infection in humans and pigs. There have been advances in genome analysis of MAH from human isolates, but studies of isolates from pigs are limited despite its potential source of infection to human. Here, we obtained 30 draft genome sequences of MAH from pigs reared in Japan. The 30 draft genomes were 4,848,678-5,620,788 bp in length, comprising 4652-5388 coding genes and 46-75 (median: 47) tRNAs. All isolates had restriction modification-associated genes and 185-222 predicted virulence genes. Two isolates had tRNA arrays and one isolate had a clustered regularly interspaced short palindromic repeat (CRISPR) region. Our results will be useful for evaluation of the ecology of MAH by providing a foundation for genome-based epidemiological studies.

11.
Sci Rep ; 10(1): 17997, 2020 10 22.
Artículo en Inglés | MEDLINE | ID: mdl-33093577

RESUMEN

Mycobacterium tuberculosis (Mtb) strains of Beijing lineage have caused great concern because of their rapid emergence of drug resistance and worldwide spread. DNA mutation rates that reflect evolutional adaptation to host responses and the appearance of drug resistance have not been elucidated in human-infected Beijing strains. We tracked and obtained an original Mtb isolate of Beijing lineage from the 1999 tuberculosis outbreak in Japan, as well as five other isolates that spread in humans, and two isolates from the patient caused recurrence. Three isolates were from patients who developed TB within one year after infection (rapid-progressor, RP), and the other three isolates were from those who developed TB more than one year after infection (slow-progressor, SP). We sequenced genomes of these isolates and analyzed the propensity and rate of genomic mutations. Generation time versus mutation rate curves were significantly higher for RP. The ratio of oxidative versus non-oxidation damages induced mutations was higher in SP than RP, suggesting that persistent Mtb are exposed to oxidative stress in the latent state. Our data thus demonstrates that higher mutation rates of Mtb Beijing strains during human infection is likely to account for the higher adaptability and an emergence ratio of drug resistance.


Asunto(s)
ADN Bacteriano/genética , Farmacorresistencia Bacteriana/genética , Evolución Molecular , Genoma Bacteriano , Mutación , Mycobacterium tuberculosis/genética , Tuberculosis/microbiología , Beijing , ADN Bacteriano/análisis , Humanos , Japón/epidemiología , Tasa de Mutación , Mycobacterium tuberculosis/aislamiento & purificación , Mycobacterium tuberculosis/patogenicidad , Tuberculosis/epidemiología , Tuberculosis/genética
12.
Emerg Infect Dis ; 26(11): 2728-2732, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33079053

RESUMEN

We report 2 case-patients in Japan with Mycobacterium shigaense pulmonary infections. One patient was given aggressive treatment and the other conservative treatment, according to distinctive radiologic evidence. A close phylogenetic relationship based on whole-genome sequencing was found between strain from the conservatively treated patient and a reference strain of cutaneous origin.


Asunto(s)
Enfermedades Pulmonares/microbiología , Infecciones por Mycobacterium no Tuberculosas , Mycobacterium , Humanos , Japón , Infecciones por Mycobacterium no Tuberculosas/diagnóstico , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico , Filogenia
13.
J Antimicrob Chemother ; 75(7): 1722-1725, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32303065

RESUMEN

OBJECTIVES: Bacterial population kinetics of strains harbouring drug resistance-conferring mutations within a patient often show cryptic resistance in clinical practice. We report a case that showed emergence and dominance of Mycobacterium tuberculosis with uncommon rpoB and gyrA mutations, followed by an rpoC compensatory mutation, during treatment. METHODS: A pre-XDR-TB patient showed heteroresistance to rifampicin and levofloxacin during treatment as a result of intermittent self-cessation. WGS was applied to investigate intra-host strain composition using five pairs of isolates from sputum samples. RESULTS: The subclone in this study possessed rare mutations conferring resistance to rifampicin (rpoB V170F) and levofloxacin (gyrA S91P) and it rapidly outcompeted other subclones during treatment that included levofloxacin but not rifampicin (<7 days). The high-probability compensatory mutation rpoC V483A also emerged and became dominant subsequent to the rpoB V170F mutation. CONCLUSIONS: To the best of our knowledge, this is the first case showing the emergence of such a rare variant that dominated the population within a patient during treatment of TB.


Asunto(s)
Tuberculosis Extensivamente Resistente a Drogas , Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Antituberculosos/farmacología , Antituberculosos/uso terapéutico , Tuberculosis Extensivamente Resistente a Drogas/tratamiento farmacológico , Humanos , Cinética , Pruebas de Sensibilidad Microbiana , Mutación , Mycobacterium tuberculosis/genética , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico
14.
BMC Genomics ; 20(1): 752, 2019 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-31623552

RESUMEN

BACKGROUND: The rapid identification of lineage remains a challenge in the genotyping of clinical isolates of recombinogenic pathogens. The chromosome of Mycobacterium avium subsp. hominissuis (MAH), an agent of Mycobacterium avium complex (MAC) lung disease, is often mosaic and is composed of chromosomal segments originating from different lineages. This makes it difficult to infer the MAH lineage in a simple experimental set-up. To overcome this difficulty, we sought to identify chromosomal marker genes containing lineage-specific alleles by genome data mining. RESULTS: We conducted genetic population structure analysis, phylogenetic analysis, and a survey of historical recombination using data from 125 global MAH isolates. Six MAH lineages (EA1, EA2, SC1, SC2, SC3, and SC4) were identified in the current dataset. One P-450 gene (locus_tag MAH_0788/MAV_0940) in the recombination-cold region was found to have multiple alleles that could discriminate five lineages. By combining the information about allele type from one additional gene, the six MAH lineages as well as other M. avium subspecies were distinguishable. A recombination-cold region of 116 kb contains an insertion hotspot and is flanked by a mammalian cell-entry protein operon where allelic variants have previously been reported to occur. Hence, we speculate that the acquisition of lineage- or strain-specific insertions has introduced homology breaks in the chromosome, thereby reducing the chance of interlineage recombination. CONCLUSIONS: The allele types of the newly identified marker genes can be used to predict major lineages of M. avium. The single nucleotide polymorphism typing approach targeting multiallelic loci in recombination-cold regions will facilitate the epidemiological study of MAC, and may also be useful for equivalent studies of other nontuberculous mycobacteria potentially carrying mosaic genomes.


Asunto(s)
Genes Bacterianos/genética , Epidemiología Molecular/métodos , Infección por Mycobacterium avium-intracellulare/microbiología , Mycobacterium/genética , Alelos , Animales , Mapeo Cromosómico , Ligamiento Genético , Variación Genética , Genética de Población , Genoma Bacteriano/genética , Genotipo , Humanos , Mycobacterium/clasificación , Mycobacterium/aislamiento & purificación , Infección por Mycobacterium avium-intracellulare/epidemiología , Filogenia , Recombinación Genética
15.
J Infect Public Health ; 12(6): 867-872, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31204116

RESUMEN

BACKGROUND: We conducted active surveillance to elucidate the distribution of Streptococcus pneumoniae serotypes causing invasive pneumococcal disease (IPD) and clarified the genetic relatedness among the isolates in Kobe City, Japan. METHODS: Forty-five IPD-causing S. pneumoniae strains were analyzed from March 2016 to May 2018 through active surveillance in Kobe City, Hyogo, Japan. Serotypes were determined by multiplex serotyping PCR and the Quellung reaction with pneumococcal antisera. Fourteen Sp12F strains were subjected to whole-genome sequencing (WGS). RESULTS: Among 45 isolates, the most frequent serotypes were 12F (n=14, 31%), 24F (n=5, 11%), and 10A (n=4, 9%). Multilocus sequence typing (MLST) analysis of 14 isolates of Sp12F divided them into ST4846 (n=4) and ST6495 (n=10). WGS showed clonality of the 10 isolates of ST6495, with only 13 single nucleotide polymorphisms in the genomes. Meanwhile, ST4846 strains in Kobe differed from only the outbreak strains of Sp12F ST4846 in Tsuruoka, Japan, reported on 2018. CONCLUSIONS: Serotype monitoring showed Sp12F to be the predominant serotype in Kobe, and WGS revealed the clonal spread of Sp12F ST6495 in this city. Thus, the spread of Sp12F could become a serious public health problem in Japan, warranting thorough monitoring in future.


Asunto(s)
Bacteriemia/microbiología , Meningitis Bacterianas/microbiología , Infecciones Neumocócicas/microbiología , Serogrupo , Streptococcus pneumoniae/clasificación , Streptococcus pneumoniae/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Bacteriemia/epidemiología , Niño , Preescolar , Femenino , Genotipo , Humanos , Lactante , Recién Nacido , Japón/epidemiología , Masculino , Meningitis Bacterianas/epidemiología , Persona de Mediana Edad , Epidemiología Molecular , Tipificación de Secuencias Multilocus , Infecciones Neumocócicas/epidemiología , Serotipificación , Streptococcus pneumoniae/genética , Adulto Joven
16.
Infect Genet Evol ; 74: 103923, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31207401

RESUMEN

Japan reportedly has high incidence rate of nontuberculous mycobacterial lung disease (14.7 cases per 100,000 person in 2014). In Japan, the most common etiology is Mycobacterium avium subsp. hominissuis (MAH). MAH is a typical inhabitant of the environment, especially bathrooms, which are considered as a potential source of infection. To corroborate this hypothesis, we determined the detection rate of MAH in bathrooms of healthy volunteers by an ordinary culture method and we analyzed the genetic relatedness of these isolates with those from patients and other sources. We collected swabs of bathtub inlets, showerheads, bathroom drains, and shower water from 180 residences throughout Japan. The overall MAH detection rate was 16.1%, but the rate varied among regions: it was high in Kanto (9/34, 26.5%) and Kinki (9/33, 27.3%), but low in Kyushu (0/11, 0%), Tohoku (1/23, 4.3%), and Hokkaido (2/23, 8.7%). MAH was detected primarily in bathtub inlet samples (25 out of 170 residences). Variable numbers of tandem repeats (VNTR) analysis was used to examine the genetic relatedness of 57 MAH isolates from bathrooms of the healthy volunteers with human clinical isolates. A minimum spanning tree generated on the basis of the VNTR data indicated that isolates from the bathrooms of the healthy volunteers had a high degree of genetic relatedness with those from Japanese patients, bathrooms of patients, and river water, but not with those from Russian patients and Japanese pigs. These results showed that bathtub inlets in Japan provide an environmental niche for MAH and suggest that bathrooms are one of the important infection sources of MAH in Japan. Understanding country-specific lifestyle habits, such as bathing in Japan, as well as the genetic diversity of MAH, will help in elucidating the sources of this pathogen.


Asunto(s)
Enfermedades Pulmonares/microbiología , Repeticiones de Minisatélite , Mycobacterium avium/clasificación , Ríos/microbiología , ADN Bacteriano/genética , Voluntarios Sanos , Humanos , Japón , Mycobacterium avium/genética , Mycobacterium avium/aislamiento & purificación , Filogeografía , Federación de Rusia , Microbiología del Suelo , Cuartos de Baño , Microbiología del Agua
17.
J Microbiol Methods ; 163: 105657, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31228476

RESUMEN

OBJECTIVES: A simple, rapid, and new diagnostic test for mycobacteria, named Q Gene Mycobacteria, has been developed. It is based on multiplex PCR using primers harbouring DNA tags combined with a dipstick nucleic acid chromatography method, which does not require the denaturation of PCR products for hybridization and can identify five species of mycobacteria including Mycobacterium tuberculosis complex (MTC), Mycobacterium avium, Mycobacterium intracellulare, Mycobacterium kansasii, and Mycobacterium gordonae. This study aimed to evaluate Q Gene Mycobacteria for the accurate identification of these five species. METHODS: A total of 340 mycobacterial strains/isolates were tested, of which 159 were type strains (four MTC and 155 non-tuberculosis mycobacteria (NTM) including four subspecies) and 181 were clinical isolates (18 M. tuberculosis, two Mycobacterium bovis Bacillus Calmette et Guérin (BCG), and 161 NTM comprising 16 species) collected from eight laboratories and hospitals in Japan. Species identification of NTM isolates was performed using the DNA-DNA hybridization method and/or direct sequencing of 16S rRNA, hsp65, and rpoB genes. Q Gene Mycobacteria was compared with above conventional methods for identifying the five species. RESULTS: Q Gene Mycobacteria showed excellent concordance for species identification, specifically 99.4% (158/159) for type strains and 99.4% (180/181) for clinical isolates. The two strains that were misidentified as M. gordonae were Mycobacterium paragordonae. As they are genetically close and there is few case reports of M. paragordonae, it might not be a serious critical issue to distinguish M. paragordonae from M. gordonae. CONCLUSIONS: Q Gene Mycobacteria was able to identify frequently isolated mycobacterial species accurately and easily. Therefore, Q Gene Mycobacteria could be a useful tool for the identification of specific mycobacteria in clinical laboratories.


Asunto(s)
Genes vif , Mycobacterium tuberculosis/clasificación , Micobacterias no Tuberculosas/clasificación , Cromatografía/métodos , Genes Bacterianos , Humanos , Reacción en Cadena de la Polimerasa Multiplex/métodos , Infecciones por Mycobacterium no Tuberculosas/diagnóstico , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/aislamiento & purificación , Micobacterias no Tuberculosas/genética , Micobacterias no Tuberculosas/aislamiento & purificación , Tuberculosis/diagnóstico
18.
Artículo en Inglés | MEDLINE | ID: mdl-31086119

RESUMEN

We investigated the genetic characteristics of 161 Legionella pneumophila strains isolated over a period of 10 years from cooling towers in Japan. Minimum spanning tree analysis based on the sequence-based typing (SBT) of them identified three clonal complexes (CCs); CC1 (105/161, 65.2%), CC2 (22 /161, 13.7%), and CC3 (20/161, 12.4%). CC1 was formed by serogroup (SG) 1 and SG7, whereas CC2 was mainly formed by SG1. All of the CC3 isolates except two strains were SG13. The major sequence types (STs) in CC1 and CC2 were ST1 (88/105, 83.8%) and ST154 (15/22, 68.2%), respectively. These STs are known as typical types of L. pneumophila SG1 in Japanese cooling tower. Additionally, we identified 15 strains of ST2603 as the major type in CC3. This ST has not been reported in Japanese cooling tower. Whole genome sequencing (WGS) analysis of the representative strains in the three CCs, which were isolated from various cooling towers over the 10 years, elucidated high clonal population of L. pneumophila in Japanese cooling tower. Moreover, it revealed that the strains of CC2 are phylogenetically distant compared to those of CC1 and CC3, and belonged to L. pneumophila subsp. fraseri.


Asunto(s)
Genes Bacterianos , Legionella pneumophila/genética , Legionella pneumophila/aislamiento & purificación , Microbiología del Agua , Japón/epidemiología , Filogenia , Secuenciación Completa del Genoma
19.
PLoS One ; 14(2): e0212798, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30817803

RESUMEN

OBJECTIVES: Automated online software tools that analyse whole genome sequencing (WGS) data without the need for bioinformatics expertise can motivate the implementation of WGS-based molecular drug susceptibility testing (DST) in routine diagnostic settings for tuberculosis (TB). Pyrazinamide (PZA) is a key drug for current and future TB treatment regimens; however, it was reported that predictive power for PZA resistance by the available tools is low. Therefore, this low predictive power may make users hesitant to use the tools. This study aimed to elucidate why and to uncover the real performance of the tools when taking into account their variation calling lists (manual inspection), not just their automated reporting system (default setting) that was evaluated by previous studies. METHODS: WGS data from 191 datasets comprising 108 PZA-resistant and 83 susceptible strains were used to evaluate the potential performance of the available online tools (TB Profiler, TGS-TB, PhyResSE, and CASTB) for predicting phenotypic PZA resistance. RESULTS: When taking into consideration the variation calling lists, 73 variants in total (47 non-synonymous mutations and 26 indels) in pncA were detected by TGS-TB and PhyResSE, covering all mutations for the 108 PZA-resistant strains. The 73 variants were confirmed by Sanger sequencing. TB Profiler also detected all but three complete loss, two large deletion at the 3'-end, and one relatively large insertion of pncA. On the other hand, many of the 73 variants were lacking in the automated reporting systems except by TGS-TB; of these variants, CASTB detected only 20. By applying the 'non-wild type sequence' approach for predicting PZA resistance, accuracy of the results significantly improved compared with that of the automated results obtained by each tool. CONCLUSION: Users can obtain more accurate predictions for PZA resistance than previously reported by manually checking the results and applying the 'non-wild type sequence' approach.


Asunto(s)
Antituberculosos/farmacología , Biología Computacional/métodos , Mycobacterium tuberculosis/genética , Pirazinamida/farmacología , Amidohidrolasas/genética , Antituberculosos/uso terapéutico , Biología Computacional/instrumentación , ADN Bacteriano/genética , Conjuntos de Datos como Asunto , Farmacorresistencia Bacteriana/genética , Genoma Bacteriano/genética , Humanos , Internet , Pruebas de Sensibilidad Microbiana/métodos , Mutación , Pirazinamida/uso terapéutico , Programas Informáticos , Tuberculosis/tratamiento farmacológico , Tuberculosis/microbiología , Secuenciación Completa del Genoma
20.
Infect Genet Evol ; 62: 122-129, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29673985

RESUMEN

Mycobacterium avium subspecies hominissuis (MAH) is an important cause of infection in human pulmonary and swine intestinal cases. Although MAH is isolated from environmental sources frequently, infections of other animals have rarely been analysed. Recently, we detected granulomatous inflammation in bovine lung as an abnormal postmortem inspection case. To ascertain its genetic profile, we conducted a variable numbers of tandem repeats (VNTR) analysis and genomic characterization using deep sequencing. The VNTR type was a unique profile that differed from reported genotypes, but it was assigned within a broad genotypic complex of isolates from human patients and bathrooms. Genomic comparison with 116 registered genome sequences of the subspecies revealed that the strain was separate from five major genetic population groups proposed previously. Although the infection source remains unclear, its isolation from various resources such as animal infection cases should be elucidated more extensively to reveal its genetic diversity and ecological context.


Asunto(s)
Enfermedades de los Bovinos/microbiología , Enfermedades Pulmonares/veterinaria , Mycobacterium avium/clasificación , Mycobacterium avium/genética , Filogenia , Animales , Bovinos , Genotipo , Enfermedades Pulmonares/microbiología
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