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1.
J Health Popul Nutr ; 42(1): 146, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38129922

RESUMEN

BACKGROUND: Cholera can result in the expulsion of important microbiota from the gut and result in death if left untreated. The disease transmits mainly via drinking water carrying Vibrio cholerae; and household contacts (HHC) of cholera patients are at elevated risk during the first week of infection. The gut microbiota profiles of HHC-children of cholera patients at Dhaka city slums were investigated before (day 0) and after (day 8) delivery of chlorinated water as part of the major study 'CHoBI7 trial (cholera-hospital-based intervention for 7 days)'. RESULT: Results of sequencing and analysis of bacterial community DNA revealed the predominance of two bacterial phyla: Bacteroidetes and Firmicutes at day 0 with a relative abundance of 62 ± 6 (mean ± SEM%) and 32 ± 7, respectively. The pattern reversed at day 8 with a decreased relative abundance of Bacteroidetes (39 ± 12; p = 0.034) and an increased abundance of Firmicutes (49 ± 12; p = 0.057). Of 65 bacterial families confirmed at day 0, six belonging to Proteobacteria including Vibrionaceae disappeared at day 8. Interestingly, the relative abundance of four Firmicutes families-Lachnospiraceae, Bifidobacteriaceae, Clostridiaceae, and Ruminococcaceae was increased in all five study children at day 8. CONCLUSION: The observed exclusion of pathogenic Proteobacteria and enhancement of beneficial Firmicutes in the gut of children delivered with chlorinated water as part of WASH intervention reflect a great promise of the CHoBI7 program in preventing cholera and improving child health.


Asunto(s)
Cólera , Microbioma Gastrointestinal , Purificación del Agua , Humanos , Bangladesh , Cólera/prevención & control , Desinfección de las Manos/métodos , Estudios Prospectivos , Jabones , Purificación del Agua/métodos
2.
Diagnostics (Basel) ; 13(15)2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37568971

RESUMEN

A prostate-targeted biopsy (TB) core is usually collected from a site where magnetic resonance imaging (MRI) indicates possible cancer. However, the extent of the lesion is difficult to accurately predict using MRI or TB alone. Therefore, we performed several biopsies around the TB site (perilesional [p] TB) and analyzed the association between the positive cores obtained using TB and pTB and the Prostate Imaging Reporting and Data System (PI-RADS) scores. This retrospective study included patients who underwent prostate biopsies. The extent of pTB was defined as the area within 10 mm of a TB site. A total of 162 eligible patients were enrolled. Prostate cancer (PCa) was diagnosed in 75.2% of patients undergoing TB, with a positivity rate of 50.7% for a PI-RADS score of 3, 95.8% for a PI-RADS score of 4, and 100% for a PI-RADS score of 5. Patients diagnosed with PCa according to both TB and pTB had significantly higher positivity rates for PI-RADS scores of 4 and 5 than for a PI-RADS score of 3 (p < 0.0001 and p = 0.0009, respectively). Additional pTB may be performed in patients with PI-RADS ≥ 4 regions of interest for assessing PCa malignancy.

3.
Nat Commun ; 14(1): 1154, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36859426

RESUMEN

In 2022, one of its worst cholera outbreaks began in Bangladesh and the icddr,b Dhaka hospital treated more than 1300 patients and ca. 42,000 diarrheal cases from March-1 to April-10, 20221. Here, we present genomic attributes of V. cholerae O1 responsible for the 2022 Dhaka outbreak and 960 7th pandemic El Tor (7PET) strains from 88 countries. Results show strains isolated during the Dhaka outbreak cluster with 7PET wave-3 global clade strains, but comprise subclade BD-1.2, for which the most recent common ancestor appears to be that responsible for recent endemic cholera in India. BD-1.2 strains are present in Bangladesh since 2016, but not establishing dominance over BD-2 lineage strains2 until 2018 and predominantly associated with endemic cholera. In conclusion, the recent shift in lineage and genetic attributes, including serotype switching of BD-1.2 from Ogawa to Inaba, may explain the increasing number of cholera cases in Bangladesh.


Asunto(s)
Cólera , Vibrio cholerae O1 , Humanos , Bangladesh , Genómica , Brotes de Enfermedades , Factores de Transcripción
4.
Infect Genet Evol ; 105: 105363, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36087684

RESUMEN

Vibrio cholerae O1 El Tor, causative agent of the ongoing seventh cholera pandemic, is native to the aquatic environment of the Ganges Delta, Bay of Bengal (GDBB). Recent studies traced pandemic strains to the GDBB and proposed global spread of cholera had occurred via intercontinental transmission. In the research presented here, NotI-digested genomic DNA extracted from V. cholerae O1 clinical and environmental strains isolated in Bangladesh during 20042014 was analyzed by pulsed-field gel electrophoresis (PFGE). Results of cluster analysis showed 94.67% of the V. cholerae strains belonged to clade A and included the majority of clinical strains of spatio-temporal origin and representing different cholera endemic foci. The rest of the strains were estuarine, all environmental strains from Mathbaria, Bangladesh, and occurred as singletons, clustered in clades B and C, or in the small clades D and E. Cluster analysis of the Bangladeshi strains and including 157 El Tor strains from thirteen countries in Asia, Africa, and the Americas revealed 85% of the total set of strains belonged to clade A, indicating all were related, yet did not form an homogeneous cluster. Overall, 15% of the global strains comprised multiple small clades or segregated as singletons. Three sub-clades could be discerned within the major clade A, reflecting distinct lineages of V. cholerae O1 El Tor associated with cholera in Asia, Africa, and the Americas. The presence in Asia and the Americas of non-pandemic V. cholerae O1 El Tor populations differing by PFGE and from strains associated with cholera globally suggests different ecotypes are resident in distant geographies.


Asunto(s)
Cólera , Vibrio cholerae O1 , Humanos , Cólera/epidemiología , Electroforesis en Gel de Campo Pulsado , Toxina del Cólera/genética , Bangladesh/epidemiología
5.
mBio ; 13(2): e0384921, 2022 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-35404118

RESUMEN

Interorganellar cross talk is often mediated by membrane contact sites (MCSs), which are zones where participating membranes come within 30 nm of one another. MCSs have been found in organelles, including the endoplasmic reticulum, Golgi bodies, endosomes, and mitochondria. Despite its seeming ubiquity, reports of MCS involving mitochondrion-related organelles (MROs) present in a few anaerobic parasitic protozoa remain lacking. Entamoeba histolytica, the etiological agent of amoebiasis, possesses an MRO called the mitosome. We previously discovered several Entamoeba-specific transmembrane mitosomal proteins (ETMPs) from in silico and cell-biological analyses. One of them, ETMP1 (EHI_175060), was predicted to have one transmembrane domain and two coiled-coil regions and was demonstrated to be mitosome membrane integrated based on carbonate fractionation and immunoelectron microscopy (IEM) data. Immunoprecipitation analysis detected a candidate interacting partner, EH domain-containing protein (EHD1; EHI_105270). We expressed hemagglutinin (HA)-tagged EHD1 in E. histolytica, and subsequent immunofluorescence and IEM data indicated an unprecedented MCS between the mitosome and the endosome. Live imaging of a green fluorescent protein (GFP)-EHD1-expressing strain demonstrated that EHD1 is involved in early endosome formation and is observed in MCS between endosomes of various sizes. In vitro assays using recombinant His-EHD1 demonstrated ATPase activity. MCSs are involved in lipid transfer, ion homeostasis, and organelle dynamics. The serendipitous discovery of the ETMP1-interacting partner EHD1 led to the observation of the mitosome-endosome contact site in E. histolytica. It opened a new view of how the relic mitochondria of Entamoeba may likewise be involved in organelle cross talk, a conserved feature of mitochondria and other organelles in general. IMPORTANCE Membrane contact sites (MCSs) are key regulators of interorganellar communication and have been widely demonstrated between various organelles. However, studies on MCSs involving mitochondrion-related organelles (MROs), present in some anaerobic parasitic protozoans, remain scarce. Entamoeba histolytica, the etiological agent of amoebiasis, possesses an MRO called the mitosome. This organelle is crucial for cellular differentiation and disease transmission, thereby significantly contributing to the amoeba's parasitic lifestyle. Our recent discovery of the interaction between the Entamoeba-specific transmembrane mitosomal protein (ETMP1) and EH domain-containing protein (EHD1) showcases a newly found mitosome-endosome contact site in E. histolytica. This finding reflects the idea that despite their substantially divergent and reduced nature, MROs like mitosomes conserve mechanisms for interorganellar cross talk. We posit lipid and ion transport, mitosome fission, and quality control as potential processes that are mediated by the ETMP1-EHD1-tethered mitosome-endosome contact site in E. histolytica.


Asunto(s)
Amebiasis , Entamoeba histolytica , Entamoeba , Endosomas/metabolismo , Entamoeba histolytica/genética , Entamoeba histolytica/metabolismo , Humanos , Lípidos , Proteínas de la Membrana/metabolismo , Mitocondrias/metabolismo , Proteínas de Transporte Vesicular/metabolismo
6.
Microbiol Spectr ; 10(2): e0039122, 2022 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-35315699

RESUMEN

Comparative genomic analysis of Vibrio cholerae El Tor associated with endemic cholera in Asia revealed two distinct lineages, one dominant in Bangladesh and the other in India. An in-depth whole-genome study of V. cholerae El Tor strains isolated during endemic cholera in Bangladesh (1991 to 2017) included reference genome sequence data obtained online. Core genome phylogeny established using single nucleotide polymorphisms (SNPs) showed V. cholerae El Tor strains comprised two lineages, BD-1 and BD-2, which, according to Bayesian phylodynamic analysis, originated from paraphyletic group BD-0 around 1981. BD-1 and BD-2 lineages overlapped temporally but were negatively associated as causative agents of cholera during 2004 to 2017. Genome-wide association study (GWAS) revealed 140 SNPs and 31 indels, resulting in gene alleles unique to BD-1 and BD-2. Regression analysis of root to tip distance and year of isolation indicated early BD-0 strains at the base, whereas BD-1 and BD-2 subsequently emerged and progressed by accumulating SNPs. Pangenome analysis provided evidence of gene acquisition by both BD-1 and BD-2, of which six crucial proteins of known function were predominant in BD-2. BD-1 and BD-2 diverged and have distinctively different genomic traits, namely, heterogeneity in VSP-2, VPI-1, mobile elements, toxin encoding elements, and total gene abundance. In addition, the observed phage-inducible chromosomal island-like element (PLE1), and SXT ICE elements (ICETET) in BD-2 presumably provided a fitness advantage for the lineage to outcompete BD-1 as the etiological agent of endemic cholera in Bangladesh, with implications for global cholera epidemiology. IMPORTANCE Cholera is a global disease with specific reference to the Bay of Bengal Ganges Delta where Vibrio cholerae O1 El Tor, the causative agent of the disease showed two circulating lineages, one dominant in Bangladesh and the other in India. Results of an in-depth genomic study of V. cholerae associated with endemic cholera during the past 27 years (1991 to 2017) indicate emergence and succession of the two lineages, BD-1 and BD-2, arising from a common ancestral paraphyletic group, BD-0, comprising the early strains and short-term evolution of the bacterium in Bangladesh. Among the two V. cholerae lineages, BD-2 supersedes BD-1 and is predominant in the most recent endemic cholera in Bangladesh. The BD-2 lineage contained significantly more SNPs and indels, and showed richness in gene abundance, including antimicrobial resistance genes, gene cassettes, and PLE to fight against bacteriophage infection, acquired over time. These findings have important epidemic implications on a global scale.


Asunto(s)
Cólera , Vibrio cholerae O1 , Bangladesh/epidemiología , Teorema de Bayes , Cólera/epidemiología , Cólera/microbiología , Toxina del Cólera/genética , Toxina del Cólera/metabolismo , Estudio de Asociación del Genoma Completo , Genómica/métodos , Humanos , Vibrio cholerae O1/genética
7.
Asian J Psychiatr ; 67: 102917, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34875558

RESUMEN

PURPOSE: To compare the real-world effectiveness of antipsychotic treatments focusing on long-acting injectable antipsychotic medications (LAIs) and antipsychotic polytherapies except polytherapy involving clozapine (APEC) for patients with schizophrenia. METHODS: This prospective study was conducted over a 19-month period in 12 psychiatric emergency hospitals in Japan. Patients who were newly admitted to psychiatric emergency wards between September 2019 and March 2020 because of acute onset or exacerbation of Schizophrenia and Other Psychotic Disorders as defined by the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, were included. All patients were followed for one-year after discharge or until March 31, 2021. The primary outcome was the risk of treatment failure defined as psychiatric rehospitalization, discontinuation of medication, death, or continuation of hospitalization for one year. Cox proportional hazards multivariate regression was used for analyses. RESULTS: A total of 1011 patients were enrolled (women, 53.7%; mean [SD] age, 47.5 [14.8] years). During follow-up, 588 patients (58.2%) experienced treatment failure including rehospitalization (513 patients), discontinuation of medication (17 patients), death (11 patients), and continuation of hospitalization for one-year (47 patients). Switching to LAIs (hazard ratio [HR] 0.810, 95%CI 0.659-0.996) and APEC (HR 0.829, 95%CI 0.695-0.990) were significantly associated with a low rate of treatment failure. CONCLUSIONS: Switching to LAIs and APEC in early non-responders seems to be beneficial for the prevention of treatment failure in acutely admitted patients with schizophrenia. The risk of treatment failure was about 19% and 17% lower in patients treated with LAIs and APEC, respectively, than in patients treated without them.


Asunto(s)
Antipsicóticos , Esquizofrenia , Antipsicóticos/uso terapéutico , Preparaciones de Acción Retardada/uso terapéutico , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Esquizofrenia/tratamiento farmacológico
8.
Jpn J Infect Dis ; 74(1): 79-81, 2021 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-32741928

RESUMEN

Five novel strains of Serratia fonticola that produce FONA, a minor extended-spectrum beta-lactamase (ESBL), were isolated during routine surveillance of ESBL-producing Enterobacteriaceae in imported chicken meat in Japan in 2017 and 2018. These strains exhibited a clear ESBL phenotype in susceptibility tests carried out in the presence of clavulanic acid; however, all strains tested negative in a multiplex polymerase chain reaction assay used to detect TEM, SHV, and CTX-M ß-lactamase genes. After identification of the bacterial species as S. fonticola, full length blaFONA genes were amplified and the DNA sequences were determined. The blaFONA genes from all 5 strains were different from those previously reported (blaFONA-1 to blaFONA-6); they clustered close to one another but were distinct from previously reported blaFONA genes in a phylogenic analysis based on amino acid sequences.


Asunto(s)
Proteínas Bacterianas/metabolismo , Carne/microbiología , Serratia/aislamiento & purificación , beta-Lactamasas/metabolismo , Animales , Proteínas Bacterianas/genética , Pollos , Enterobacteriaceae/enzimología , Enterobacteriaceae/genética , Enterobacteriaceae/aislamiento & purificación , Infecciones por Enterobacteriaceae/microbiología , Contaminación de Alimentos/análisis , Microbiología de Alimentos/métodos , Humanos , Japón , Pruebas de Sensibilidad Microbiana , Serratia/enzimología , Serratia/genética
9.
J Infect Chemother ; 26(2): 157-161, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31735631

RESUMEN

Streptococcus pyogenes (group A streptococcus; GAS) is an important gram-positive human pathogen capable of causing diseases ranging from mild superficial skin and pharyngeal infections to more severe invasive diseases, including streptococcal toxic shock syndrome (STSS). GAS produces a T protein, and T serotyping has considerable discriminatory power for epidemiological characterization of GAS. To clarify the relationship between STSS and pharyngitis in Japan, we examined the T serotypes of GAS strains isolated from clinical specimens of streptococcal infections (STSS, 951 isolates; pharyngitis, 16268 isolates) from 2005 to 2017. The most prevalent T serotype from pharyngitis isolates was T12, followed by T1, T4, and TB3264. The most prevalent T serotype from STSS isolates was T1, followed by TB3264. Trend of increase and decrease in the frequency of T1 or TB3264 isolation from pharyngitis was correlated with that of STSS patients. The increase of T1 or TB3264 strain-infection in pharyngitis patients may increase the probability of causing STSS, indicating that careful monitoring of GAS serotypes is essential for the prediction of rapid increase of STSS in time to develop effective management strategies.


Asunto(s)
Faringitis/microbiología , Choque Séptico/microbiología , Infecciones Estreptocócicas/microbiología , Streptococcus pyogenes/clasificación , Streptococcus pyogenes/aislamiento & purificación , Humanos , Japón , Faringitis/epidemiología , Serotipificación , Choque Séptico/epidemiología , Infecciones Estreptocócicas/epidemiología
11.
Front Microbiol ; 10: 2766, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31849903

RESUMEN

Extended-spectrum ß-lactamases (ESBLs) form the most important resistance determinants prevalent worldwide. Data on ESBL-producing Escherichia coli from poultry and livestock are scarce in India. We present data on the functional and genomic characterization of ESBL-producing E. coli obtained from poultry in India. The whole genome sequences of 28 ESBL-producing E. coli were analyzed comprising of 12 broiler chicken E. coli isolates, 11 free-range chicken E. coli isolates, and 5 human extraintestinal pathogenic E. coli. All of the 28 ESBL-producing E. coli isolates were tested for antibiotic susceptibilities, in vitro conjugation, and virulence-associated phenotypic characteristics. A total of 13 sequence types were identified from the poultry E. coli, which included globally successful sequence types such as ST117 (9%), ST131 (4.3%), and ST10 (4.3%). The most common ESBL gene detected in poultry E. coli genomes was bla CTX-M-15 (17%). Also, FIB (73%) and FII (73%) were the most common plasmid replicons identified. Conjugation experiments demonstrated 54 (7/13), 30 (3/10), and 40% (2/5) of broiler, free-range, and human ExPEC E. coli to be able to transfer their ESBL genes, respectively. The in vitro virulence-associated phenotypic tests revealed the broiler, free-range, and human ExPEC isolates to be comparable in biofilm formation, resistance to serum bactericidal activity, adherence, and invasion capabilities. Our overall results showed prevalence of virulence phenotypes among the diverse ESBL-producing E. coli from poultry; while certain E. coli clones from broiler-poultry may indeed have the potential to cause infection in humans.

12.
Cell Rep ; 27(2): 561-571.e6, 2019 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-30970258

RESUMEN

Severe invasive group A Streptococcus (GAS) infection evades anti-bacterial immunity by attenuating the cellular components of innate immune responses. However, this loss of protection is compensated for by interferon (IFN)-γ-producing immature myeloid cells (γIMCs), which are selectively recruited upon severe invasive GAS infection in mice. Here, we demonstrate that γIMCs provide this IFN-γ-mediated protection by sequentially sensing GAS through two distinct pattern recognition receptors. In a mouse model, GAS is initially recognized by Toll-like receptor 2 (TLR2), which promptly induces interleukin (IL)-6 production in γIMCs. γIMC-derived IL-6 promotes the upregulation of a recently identified GAS-sensing receptor, macrophage-inducible C-type lectin (Mincle), in an autocrine or paracrine manner. Notably, blockade of γIMC-derived IL-6 abrogates Mincle expression, downstream IFN-γ production, and γIMC-mediated protection against severe invasive GAS infection. Thus, γIMCs regulate host protective immunity against severe invasive GAS infection via a TLR2-IL-6-Mincle axis.


Asunto(s)
Lectinas Tipo C/inmunología , Proteínas de la Membrana/inmunología , Células Mieloides/inmunología , Infecciones Estreptocócicas/inmunología , Receptor Toll-Like 2/inmunología , Animales , Inmunidad Innata/inmunología , Interferón gamma/inmunología , Interleucina-6/inmunología , Macrófagos/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Células RAW 264.7 , Streptococcus pyogenes/inmunología , Streptococcus pyogenes/patogenicidad
13.
Asian J Psychiatr ; 40: 82-87, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30772732

RESUMEN

PURPOSE: The effectiveness of antipsychotic treatments in the acute phase of schizophrenia in actual clinical practice remains somewhat unclear. Therefore, the purpose of the present naturalistic, multi-center study conducted from 1 year starting in September 2017 was to examine the response rate to an initial or second antipsychotic in newly admitted patients with acute-phase schizophrenia, as well as the response rate and quality of augmentation with two antipsychotics in patients who failed to respond to both the initial and second antipsychotics. RESULTS: In total, there were 660 (42.8%) and 243 (15.7%) responders to an initial and a second antipsychotic, respectively; thus, 58.5% of all patients were responders to an initial or second antipsychotic. Among 581 nonresponders (37.7%), the initial antipsychotic or a third antipsychotic was added to the second antipsychotic. Among these patients, 89.8% showed a Clinical Global Impression-Improvement score ≤3 (from 'minimally improved' to 'very much improved'). The rates of adverse events such as hyperglycemia, hyper-low-density lipoprotein cholesterolemia, hypertriglyceridemia, hyperprolactinemia, QTc prolongation, and extrapyramidal symptoms were not high in patients receiving augmentation with two antipsychotics compared with all patients, and no serious adverse events were reported. CONCLUSION: Antipsychotic augmentation may be an option in acute-phase treatment for patients who do not respond to either an initial or a second antipsychotic.


Asunto(s)
Antipsicóticos/farmacología , Evaluación de Resultado en la Atención de Salud , Esquizofrenia/dietoterapia , Enfermedad Aguda , Adulto , Antipsicóticos/administración & dosificación , Antipsicóticos/efectos adversos , Quimioterapia Combinada , Servicios de Urgencia Psiquiátrica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polifarmacia
15.
mBio ; 9(6)2018 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-30538184

RESUMEN

While Neisseria meningitidis typically exists in an asymptomatic nasopharyngeal carriage state, it may cause potentially lethal diseases in humans, such as septicemia or meningitis, by invading deeper sites in the body. Since the nutrient compositions of human cells are not always conducive to meningococci, N. meningitidis needs to exploit nutrients from host environments. In the present study, the utilization of cysteine by the meningococcal cysteine transport system (CTS) was analyzed for the pathogenesis of meningococcal infections. A N. meningitidis strain deficient in one of the three cts genes annotated as encoding cysteine-binding protein (cbp) exhibited approximately 100-fold less internalization into human brain microvascular endothelial cells (HBMEC) than the wild-type strain. This deficiency was restored by complementation with the three cts genes together, and the infectious phenotype of HBMEC internalization correlated with cysteine uptake activity. However, efficient accumulation of ezrin was observed beneath the cbp mutant. The intracellular survival of the cbp mutant in HBMEC was markedly reduced, whereas equivalent reductions of glutathione concentrations and of resistance to reactive oxygens species in the cbp mutant were not found. The cbp mutant grew well in complete medium but not in synthetic medium supplemented with less than 300 µM cysteine. Taking cysteine concentrations in human cells and other body fluids, including blood and cerebrospinal fluid, into consideration, the present results collectively suggest that the meningococcal CTS is crucial for the acquisition of cysteine from human cells and participates in meningococcal nutrient virulence.IMPORTANCENeisseria meningitidis colonizes at a nasopharynx of human as a unique host and has many strains that are auxotrophs for amino acids for their growth. To cause invasive meningococcal diseases (IMD) such as sepsis and meningitis, N. meningitidis passes through epithelial and endothelial barriers and infiltrates into blood and cerebrospinal fluid as well as epithelial and endothelial cells. However, meningococcal nutrients, including cysteine, become less abundant when it more deeply infiltrates the human body even during inflammation, such that N. meningitidis has to acquire nutrients in order to survive/persist, disseminate, and proliferate in humans. This was the first study to examine the relationship between meningococcal cysteine acquisition and the pathogenesis of meningococcal infections. The results of the present study provide insights into the mechanisms by which pathogens with auxotrophs acquire nutrients in hosts and may also contribute to the development of treatments and prevention strategies for IMD.


Asunto(s)
Cisteína/metabolismo , Células Endoteliales/microbiología , Proteínas de Transporte de Membrana/metabolismo , Viabilidad Microbiana , Neisseria meningitidis/crecimiento & desarrollo , Neisseria meningitidis/metabolismo , Factores de Virulencia/metabolismo , Células Cultivadas , Medios de Cultivo/química , Endocitosis , Eliminación de Gen , Prueba de Complementación Genética , Humanos , Proteínas de Transporte de Membrana/deficiencia , Neisseria meningitidis/genética , Virulencia , Factores de Virulencia/deficiencia
16.
Gut Pathog ; 9: 58, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29075330

RESUMEN

Of 19 environmental Escherichia coli (n = 12) and Klebsiella pneumoniae (n = 7) tested for quinolone resistance-related genes qnrA, qnrB, qnrC, qnrS and qepA, four each of E. coli and K. pneumoniae possessed qnrS, and another E. coli isolate possessed a new variant of qepA. This is the first detection of qepA in environmentally dwelling bacteria in Bangladesh.

17.
mBio ; 8(5)2017 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-29066550

RESUMEN

Escherichia coli sequence type 131 (ST131), a pandemic clone responsible for the high incidence of extraintestinal pathogenic E. coli (ExPEC) infections, has been known widely for its contribution to the worldwide dissemination of multidrug resistance. Although other ExPEC-associated and extended-spectrum-ß-lactamase (ESBL)-producing E. coli clones, such as ST38, ST405, and ST648 have been studied widely, no comparative genomic data with respect to other genotypes exist for ST131. In this study, comparative genomic analysis was performed for 99 ST131 E. coli strains with 40 genomes from three other STs, including ST38 (n = 12), ST405 (n = 10), and ST648 (n = 18), and functional studies were performed on five in-house strains corresponding to the four STs. Phylogenomic analysis results from this study corroborated with the sequence type-specific clonality. Results from the genome-wide resistance profiling confirmed that all strains were inherently multidrug resistant. ST131 genomes showed unique virulence profiles, and analysis of mobile genetic elements and their associated methyltransferases (MTases) has revealed that several of them were missing from the majority of the non-ST131 strains. Despite the fact that non-ST131 strains lacked few essential genes belonging to the serum resistome, the in-house strains representing all four STs demonstrated similar resistance levels to serum antibactericidal activity. Core genome analysis data revealed that non-ST131 strains usually lacked several ST131-defined genomic coordinates, and a significant number of genes were missing from the core of the ST131 genomes. Data from this study reinforce adaptive diversification of E. coli strains belonging to the ST131 lineage and provide new insights into the molecular mechanisms underlying clonal diversification of the ST131 lineage.IMPORTANCEE. coli, particularly the ST131 extraintestinal pathogenic E. coli (ExPEC) lineage, is an important cause of community- and hospital-acquired infections, such as urinary tract infections, surgical site infections, bloodstream infections, and sepsis. The treatment of infections caused by ExPEC has become very challenging due to the emergence of resistance to the first-line as well as the last-resort antibiotics. This study analyzes E. coli ST131 against three other important and globally distributed ExPEC lineages (ST38, ST405, and ST648) that also produced extended-spectrum ß-lactamase (ESBL). This is perhaps the first study that employs the high-throughput whole-genome sequence-based approach to compare and study the genomic features of these four ExPEC lineages in relation to their functional properties. Findings from this study highlight the differences in the genomic coordinates of ST131 with respect to the other STs considered here. Results from this comparative genomics study can help in advancing the understanding of ST131 evolution and also offer a framework towards future developments in pathogen identification and targeted therapeutics to prevent diseases caused by this pandemic E. coli ST131 clone.


Asunto(s)
Infecciones por Escherichia coli/microbiología , Escherichia coli/genética , Escherichia coli Patógena Extraintestinal/genética , Genoma Bacteriano , Antibacterianos/farmacología , Hibridación Genómica Comparativa , Infección Hospitalaria/microbiología , Farmacorresistencia Bacteriana Múltiple/genética , Evolución Molecular , Escherichia coli Patógena Extraintestinal/clasificación , Escherichia coli Patógena Extraintestinal/aislamiento & purificación , Genómica/métodos , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus , Virulencia/genética , Factores de Virulencia/genética , beta-Lactamasas/genética
18.
Gut Pathog ; 9: 19, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28439298

RESUMEN

BACKGROUND: The gut of human harbors diverse commensal microbiota performing an array of beneficial role for the hosts. In the present study, the major commensal gut bacteria isolated by culturing methods from 15 children of moderate income families, aged between 10 and 24 months, were studied for their response to different antibiotics, and the molecular basis of drug resistance. RESULTS: Of 122 bacterial colonies primarily selected from Luria-Bertani agar, bacterial genera confirmed by analytical profile index (API) 20E® system included Escherichia as the predominant (52%) organism, followed by Enterobacter (16%), Pseudomonas (12%), Klebsiella (6%), Pantoea (6%), Vibrio (3%), and Citrobacter (3%); while Aeromonas and Raoultella were identified as the infrequently occurring genera. An estimated 11 and 22% of the E. coli isolates carried virulence marker genes stx-2 and eae, respectively. Antimicrobial susceptibility assay revealed 78% of the gut bacteria to be multidrug resistant (MDR) with highest resistance to erythromycin (96%), followed by ampicillin (63%), tetracycline (59%), azithromycin (53%), sulfamethoxazole-trimethoprim (43%), cefixime (39%), and ceftriaxone (33%). PCR assay results revealed 56% of the gut bacteria to possess gene cassette Class 1 integron; while 8, 17.5 and 6% of the strains carried tetracycline resistance-related genes tetA, tetB, and tetD, respectively. The macrolide (erythromycin and azithromycin) resistance marker genes mphA, ereB, and ermB were found in 28, 3 and 5% of bacterial isolates, respectively; while 26, 12, 17, 32, 7, 4 and 3% of the MDR bacterial isolates carried the extended spectrum ß-lactamase (ESBL)-related genes e.g., blaTEM, blaSHV, blaCMY-9, blaCTX-M1, blaCTX-M2, blaCMY-2 and blaOXA respectively. Majority of the MDR gut bacteria harbored large plasmids [e.g., 140 MDa (43%), 105 MDa (30%), 90 MDa (14%)] carrying invasion and related antibiotic resistance marker genes. CONCLUSIONS: Our results suggest gut of young Bangladeshi children to be an important reservoir for multi-drug resistant pathogenic bacteria carrying ESBL related genes.

20.
Clin Infect Dis ; 63(8): 1087-1093, 2016 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-27439526

RESUMEN

Antimicrobial use in food animals selects for antimicrobial resistance in bacteria, which can spread to people. Reducing use of antimicrobials-particularly those deemed to be critically important for human medicine-in food production animals continues to be an important step for preserving the benefits of these antimicrobials for people. The World Health Organization ranking of antimicrobials according to their relative importance in human medicine was recently updated. Antimicrobials considered the highest priority among the critically important antimicrobials were quinolones, third- and fourth-generation cephalosporins, macrolides and ketolides, and glycopeptides. The updated ranking allows stakeholders in the agriculture sector and regulatory agencies to focus risk management efforts on drugs used in food animals that are the most important to human medicine. In particular, the current large-scale use of fluoroquinolones, macrolides, and third-generation cephalosporins and any potential use of glycopeptides and carbapenems need to be addressed urgently.


Asunto(s)
Antiinfecciosos , Farmacorresistencia Microbiana , Control de Medicamentos y Narcóticos , Inocuidad de los Alimentos , Animales , Antiinfecciosos/farmacología , Antiinfecciosos/uso terapéutico , Humanos , Gestión de Riesgos , Organización Mundial de la Salud
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