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1.
Cell ; 184(13): 3376-3393.e17, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34043940

RESUMO

We present a global atlas of 4,728 metagenomic samples from mass-transit systems in 60 cities over 3 years, representing the first systematic, worldwide catalog of the urban microbial ecosystem. This atlas provides an annotated, geospatial profile of microbial strains, functional characteristics, antimicrobial resistance (AMR) markers, and genetic elements, including 10,928 viruses, 1,302 bacteria, 2 archaea, and 838,532 CRISPR arrays not found in reference databases. We identified 4,246 known species of urban microorganisms and a consistent set of 31 species found in 97% of samples that were distinct from human commensal organisms. Profiles of AMR genes varied widely in type and density across cities. Cities showed distinct microbial taxonomic signatures that were driven by climate and geographic differences. These results constitute a high-resolution global metagenomic atlas that enables discovery of organisms and genes, highlights potential public health and forensic applications, and provides a culture-independent view of AMR burden in cities.


Assuntos
Farmacorresistência Bacteriana/genética , Metagenômica , Microbiota/genética , População Urbana , Biodiversidade , Bases de Dados Genéticas , Humanos
2.
EMBO J ; 42(5): e111484, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36592032

RESUMO

Plant pathogens compromise crop yields. Plants have evolved robust innate immunity that depends in part on intracellular Nucleotide-binding, Leucine rich-Repeat (NLR) immune receptors that activate defense responses upon detection of pathogen-derived effectors. Most "sensor" NLRs that detect effectors require the activity of "helper" NLRs, but how helper NLRs support sensor NLR function is poorly understood. Many Solanaceae NLRs require NRC (NLR-Required for Cell death) class of helper NLRs. We show here that Rpi-amr3, a sensor NLR from Solanum americanum, detects AVRamr3 from the potato late blight pathogen, Phytophthora infestans, and activates oligomerization of helper NLRs NRC2 and NRC4 into high-molecular-weight resistosomes. In contrast, recognition of P. infestans effector AVRamr1 by another sensor NLR Rpi-amr1 induces formation of only the NRC2 resistosome. The activated NRC2 oligomer becomes enriched in membrane fractions. ATP-binding motifs of both Rpi-amr3 and NRC2 are required for NRC2 resistosome formation, but not for the interaction of Rpi-amr3 with its cognate effector. NRC2 resistosome can be activated by Rpi-amr3 upon detection of AVRamr3 homologs from other Phytophthora species. Mechanistic understanding of NRC resistosome formation will underpin engineering crops with durable disease resistance.


Assuntos
Proteínas NLR , Plantas , Proteínas NLR/metabolismo , Plantas/metabolismo , Resistência à Doença , Domínios Proteicos , Imunidade Vegetal , Doenças das Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
3.
Trends Biochem Sci ; 47(8): 673-688, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35487808

RESUMO

Rapid phenotypic antimicrobial susceptibility testing (AST) requires the enrichment of live bacteria from patient samples, which is particularly challenging in the context of life-threatening bloodstream infections (BSIs) due to low bacterial titers. Over two decades, an extensive array of pathogen-specific biomolecules has been identified to capture live bacteria. The prevailing biomolecules are immune proteins of the complement system, antibodies, aptamers, phage proteins, and antimicrobial peptides. These biomolecules differ by their binder generation technologies and exhibit highly variable specificities, ranging from bacterial strains to most pathogenic bacteria. Here, we summarize how these diverse biomolecules were identified, list examples of successfully reported capture assays, and provide an outlook on the use of nanobodies raised against conserved surface-accessible proteins as promising biomolecules for pathogen capture.


Assuntos
Bactérias , Bacteriófagos , Humanos
4.
Brief Bioinform ; 25(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38706320

RESUMO

The advent of rapid whole-genome sequencing has created new opportunities for computational prediction of antimicrobial resistance (AMR) phenotypes from genomic data. Both rule-based and machine learning (ML) approaches have been explored for this task, but systematic benchmarking is still needed. Here, we evaluated four state-of-the-art ML methods (Kover, PhenotypeSeeker, Seq2Geno2Pheno and Aytan-Aktug), an ML baseline and the rule-based ResFinder by training and testing each of them across 78 species-antibiotic datasets, using a rigorous benchmarking workflow that integrates three evaluation approaches, each paired with three distinct sample splitting methods. Our analysis revealed considerable variation in the performance across techniques and datasets. Whereas ML methods generally excelled for closely related strains, ResFinder excelled for handling divergent genomes. Overall, Kover most frequently ranked top among the ML approaches, followed by PhenotypeSeeker and Seq2Geno2Pheno. AMR phenotypes for antibiotic classes such as macrolides and sulfonamides were predicted with the highest accuracies. The quality of predictions varied substantially across species-antibiotic combinations, particularly for beta-lactams; across species, resistance phenotyping of the beta-lactams compound, aztreonam, amoxicillin/clavulanic acid, cefoxitin, ceftazidime and piperacillin/tazobactam, alongside tetracyclines demonstrated more variable performance than the other benchmarked antibiotics. By organism, Campylobacter jejuni and Enterococcus faecium phenotypes were more robustly predicted than those of Escherichia coli, Staphylococcus aureus, Salmonella enterica, Neisseria gonorrhoeae, Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii, Streptococcus pneumoniae and Mycobacterium tuberculosis. In addition, our study provides software recommendations for each species-antibiotic combination. It furthermore highlights the need for optimization for robust clinical applications, particularly for strains that diverge substantially from those used for training.


Assuntos
Antibacterianos , Fenótipo , Antibacterianos/farmacologia , Aprendizado de Máquina , Farmacorresistência Bacteriana/genética , Biologia Computacional/métodos , Genoma Bacteriano , Genoma Microbiano , Humanos , Bactérias/genética , Bactérias/efeitos dos fármacos
5.
Hum Genomics ; 18(1): 54, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816866

RESUMO

This study evaluated ten nucleic acid extraction protocols (EP1 to EP10) for measuring five endogenous antibiotic resistance genes (ARGs) in four aircraft wastewater samples (AWW1 to AWW4). The targeted ARGs, including blaCTX-M, blaNDM-1, ermB, qnrS, and tetA, encompassed highly and minimally abundant ARGs. TetA and ermB were consistently detected across four aircraft wastewater samples using the DNeasy Blood and Tissue Kit and the AllPrep PowerViral DNA/RNA kit. QnrS displayed high detection rates with specific extraction protocols and aliquot volumes. Concentrations of ARGs varied across aircraft wastewater samples, with differing extraction protocols influencing quantitative results. The concentrations of tetA, ermB, and qnrS in AWW1 were distinct, while AWW2 to AWW4 exhibited a broader range for tetA, ermB, qnrS, blaCTX-M, and blaNDM-1. EP1 consistently produced the highest concentrations for several ARGs. Collective data analysis revealed varying ARG concentrations across the ten extraction protocols, suggesting the importance of careful extraction protocol selection in ARG monitoring in aircraft wastewater samples. Based on the results, we suggest that a small sample volume (as low as 0.2 mL) may be sufficient for ARG characterization in aircraft wastewater samples. The findings also emphasize the need for considering toilet paper removal without compromising nucleic acid extraction efficiency. The study highlights promising prospects for aircraft wastewater monitoring of ARGs, calling for further investigation into the import and spread of unique ARGs through transport hubs.


Assuntos
Aeronaves , Águas Residuárias , Águas Residuárias/microbiologia , Genes Bacterianos , Resistência Microbiana a Medicamentos/genética , Humanos , Ácidos Nucleicos/genética , Ácidos Nucleicos/isolamento & purificação , Farmacorresistência Bacteriana/genética , Antibacterianos
6.
Hum Genomics ; 18(1): 72, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937848

RESUMO

BACKGROUND: Wastewater surveillance (WWS) acts as a vigilant sentinel system for communities, analysing sewage to protect public health by detecting outbreaks and monitoring trends in pathogens and contaminants. To achieve a thorough comprehension of present and upcoming practices and to identify challenges and opportunities for standardisation and improvement in WWS methodologies, two EU surveys were conducted targeting over 750 WWS laboratories across Europe and other regions. The first survey explored a diverse range of activities currently undertaken or planned by laboratories. The second survey specifically targeted methods and quality controls utilised for SARS-CoV-2 surveillance. RESULTS: The findings of the two surveys provide a comprehensive insight into the procedures and methodologies applied in WWS. In Europe, WWS primarily focuses on SARS-CoV-2 with 99% of the survey participants dedicated to this virus. However, the responses highlighted a lack of standardisation in the methodologies employed for monitoring SARS-CoV-2. The surveillance of other pathogens, including antimicrobial resistance, is currently fragmented and conducted by only a limited number of laboratories. Notably, these activities are anticipated to expand in the future. Survey replies emphasise the collective recognition of the need to enhance the accuracy of results in WWS practices, reflecting a shared commitment to advancing precision and effectiveness in WWS methodologies. CONCLUSIONS: These surveys identified a lack of standardised common procedures in WWS practices and the need for quality standards and reference materials to enhance the accuracy and reliability of WWS methods in the future. In addition, it is important to broaden surveillance efforts beyond SARS-CoV-2 to include other emerging pathogens and antimicrobial resistance to ensure a comprehensive approach to protecting public health.


Assuntos
COVID-19 , SARS-CoV-2 , Águas Residuárias , Humanos , Águas Residuárias/virologia , Águas Residuárias/microbiologia , SARS-CoV-2/efeitos dos fármacos , COVID-19/epidemiologia , COVID-19/prevenção & controle , COVID-19/virologia , Europa (Continente)/epidemiologia , Inquéritos e Questionários , Esgotos/virologia , Esgotos/microbiologia , Resistência Microbiana a Medicamentos
7.
BMC Genomics ; 25(1): 156, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38331708

RESUMO

BACKGROUND: Campylobacter spp. is the most frequent cause of bacterial food-borne gastroenteritis and a high priority antibiotic resistant bacterium according to the World Health Organization (WHO). European monitoring of thermotolerant Campylobacter spp. does not reflect the global burden of resistances already circulating within the bacterial population worldwide. METHODS: We systematically compared whole genome sequencing with comprehensive phenotypic antimicrobial susceptibility, analyzing 494 thermotolerant Campylobacter poultry isolates from Vietnam and Germany. Any discrepancy was checked by repeating the wet lab and improving the dry lab part. Selected isolates were additionally analyzed via long-read Oxford Nanopore technology, leading to closed chromosomes and plasmids. RESULTS: Overall, 22 different resistance genes and gene variants (e. g. erm(B), aph(3')-IIIa, aph(2'')-If, catA, lnu(C), blaOXA, sat4) and point mutations in three distinct genes (gyrA, 23S rRNA, rpsL) associated with AMR were present in the Campylobacter isolates. Two AMR genes were missing in the database and one falsely associated with resistance. Bioinformatic analysis based on short-read data partly failed to identify tet(O) and aadE, when the genes were present as duplicate or homologous gene variants. Intriguingly, isolates also contained different determinants, redundantly conferring resistance to chloramphenicol, gentamicin, kanamycin, lincomycin and streptomycin. We found a novel tet(W) in tetracycline sensitive strains, harboring point mutations. Furthermore, analysis based on assemblies from short-read data was impaired to identify full length phase variable aad9, due to variations of the poly-C tract within the gene. The genetic determinant responsible for gentamicin resistance of one isolate from Germany could not be identified. GyrT86I, presenting the main determinant for (fluoro-)quinolone resistance led to a rare atypical phenotype of ciprofloxacin resistance but nalidixic acid sensitivity. Long-read sequencing predicted AMR genes were mainly located on the chromosome, and rarely on plasmids. Predictions from long- and short-read sequencing, respectively, often differed. AMR genes were often organized in multidrug resistance islands (MDRI) and partially located in proximity to transposase genes, suggesting main mobilization of resistance determinants is via natural transformation and transposition in Campylobacter. CONCLUSIONS: The results of this study suggest that there is frequent resistance gene duplication, mosaicism, and mutation leading to gene variation and truncation in Campylobacter strains that have not been reported in previous studies and are missing from databases. Furthermore, there is a need for deciphering yet unknown resistance mechanisms and resistance spread in thermotolerant Campylobacter spp. that may pose a challenge to global food safety.


Assuntos
Infecções por Campylobacter , Campylobacter , Humanos , Infecções por Campylobacter/microbiologia , Farmacorresistência Bacteriana/genética , Antibacterianos/farmacologia , Campylobacter/genética , Gentamicinas , Sequenciamento Completo do Genoma , Testes de Sensibilidade Microbiana
8.
Trends Genet ; 37(1): 35-45, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32951948

RESUMO

The golden age of antibiotics has passed, and the threat of untreatable antimicrobial resistant infections is now a reality for many individuals. Understanding how bacteria resist antimicrobial treatment and regulate gene expression in response to antibiotics is an important step towards combating resistance. In this review we focus on a ubiquitous class of bacterial gene regulators termed regulatory small RNAs (sRNAs) and how they contribute to antimicrobial resistance and tolerance. Small RNAs have notable roles in modulating the composition of the bacterial envelope, and through these functions control intrinsic antimicrobial resistance in many human pathogens. Recent technical advances that allow profiling of the 'sRNA interactome' have revealed a complex post-transcriptional network of sRNA interactions that can be used to identify network hubs and regulatory bottlenecks. Sequence-specific inhibition of these sRNAs with programmable RNA-targeting therapeutics may present avenues for treating antimicrobial resistant pathogens or resensitizing to our current antibiotics.


Assuntos
Antibacterianos/farmacologia , Bactérias/genética , Resistência Microbiana a Medicamentos , Regulação Bacteriana da Expressão Gênica , Redes Reguladoras de Genes , RNA Bacteriano/genética , Pequeno RNA não Traduzido/genética , Animais , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Humanos
9.
Am J Transplant ; 24(3): 406-418, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38379280

RESUMO

HLA donor-specific antibodies (DSA) elicit alloimmune responses against the graft vasculature, leading to endothelial cell (EC) activation and monocyte infiltration during antibody-mediated rejection (AMR). AMR promotes chronic inflammation and remodeling, leading to thickening of the arterial intima termed transplant vasculopathy or cardiac allograft vasculopathy (CAV) in heart transplants. Intragraft-recipient macrophages serve as a diagnostic marker in AMR; however, their polarization and function remain unclear. In this study, we utilized an in vitro Transwell coculture system to explore the mechanisms of monocyte-to-macrophage polarization induced by HLA I DSA-activated ECs. Anti-HLA I (IgG or F(ab')2) antibody-activated ECs induced the polarization of M2 macrophages with increased CD206 expression and MMP9 secretion. However, inhibition of TLR4 signaling or PSGL-1-P-selectin interactions significantly decreased both CD206 and MMP9. Monocyte adherence to Fc-P-selectin coated plates induced M2 macrophages with increased CD206 and MMP9. Moreover, Fc-receptor and IgG interactions synergistically enhanced active-MMP9 in conjunction with P-selectin. Transcriptomic analysis of arteries from DSA+CAV+ rejected cardiac allografts and multiplex-immunofluorescent staining illustrated the expression of CD68+CD206+CD163+MMP9+ M2 macrophages within the neointima of CAV-affected lesions. These findings reveal a novel mechanism linking HLA I antibody-activated endothelium to the generation of M2 macrophages which secrete vascular remodeling proteins contributing to AMR and CAV pathogenesis.


Assuntos
Receptor 4 Toll-Like , Doenças Vasculares , Humanos , Metaloproteinase 9 da Matriz , Selectina-P , Macrófagos , Endotélio , Antígenos HLA , Aloenxertos , Imunoglobulina G
10.
Antimicrob Agents Chemother ; : e0148123, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38717093

RESUMO

Persistent urinary tract infections (UTIs) in hospitalized patients constitute an important medical problem. It is estimated that 75% of nosocomial UTIs are associated with urinary tract catheters with P. aeruginosa being a species that forms biofilms on these catheters. These infections are highly resistant to standard-of-care antibiotics, and the effects of the host immune defenses, which allows for development of persistent infections. With antibiotics losing their efficacy, new treatment options against resilient infections, such as catheter-associated urinary tract infections (CAUTIs), are critically needed. Central to our anti-biofilm approach is the manipulation of the c-di-GMP signaling pathway in P. aeruginosa to switch bacteria from the protective biofilm to the unprotected planktonic mode of life. We recently identified a compound (H6-335-P1), that stimulates the c-di-GMP degrading activity of the P. aeruginosa BifA protein which plummets the intracellular c-di-GMP content and induces dispersal of P. aeruginosa biofilm bacteria into the planktonic state. In the present study, we formulated H6-335-P1 as a hydrochloride salt (Disperazol), which is water-soluble and facilitates delivery via injection or oral administration. Disperazol can work as a monotherapy, but we observed a 100-fold improvement in efficacy when treating murine P. aeruginosa CAUTIs with a Disperazol/ciprofloxacin combination. Biologically active Disperazol reached the bladder 30 min after oral administration. Our study provides proof of concept that Disperazol can be used in combination with a relevant antibiotic for effective treatment of CAUTIs.

11.
Small ; : e2403002, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38923293

RESUMO

Van der Waals (vdW) magnetic materials have broad application prospects in next-generation spintronics. Inserting magnetic elements into nonmagnetic vdW materials can introduce magnetism and enhance various transport properties. Herein, the unconventional magnetic and magneto-transport phenomena is reported in Ni0.28TaSeS crystal by intercalating Ni atoms into nonmagnetic 2H-TaSeS matrix. Magnetic characterization reveals a canted magnetic structure in Ni0.28TaSeS, which results in an antiferromagnetic (AFM) order along the c-axis and a ferromagnetic (FM) moment in the ab-plane. The presence of spin-flop (SF) behavior can also be attributed to the canted magnetic structure. Temperature-dependent resistivity exhibits a metallic behavior with an abrupt decrease corresponding to the magnetic transition. Magneto-transport measurements demonstrate a positive magnetoresistance (MR) with a plateau that is different from conventional magnetic materials. The field-dependent Hall signal exhibits nonlinear field dependence when the material is in magnetically ordered state. These unconventional magneto-transport behaviors are attributed to the field-induced formation of a complex spin texture in Ni0.28TaSeS. In addition, it further investigated the angle dependence of MR and observed an unusual fourfold anisotropic magnetoresistance (AMR) effect. This work inspires future research on spintronic devices utilizing magnetic atom-intercalated quasi-2D materials.

12.
Brief Bioinform ; 23(1)2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-34750606

RESUMO

Due to the rapid emergence of multi-drug resistant (MDR) bacteria, existing antibiotics are becoming ineffective. So, researchers are looking for alternatives in the form of antibacterial peptides (ABPs) based medicines. The discovery of novel ABPs using wet-lab experiments is time-consuming and expensive. Many machine learning models have been proposed to search for new ABPs, but there is still scope to develop a robust model that has high accuracy and precision. In this work, we present StaBle-ABPpred, a stacked ensemble technique-based deep learning classifier that uses bidirectional long-short term memory (biLSTM) and attention mechanism at base-level and an ensemble of random forest, gradient boosting and logistic regression at meta-level to classify peptides as antibacterial or otherwise. The performance of our model has been compared with several state-of-the-art classifiers, and results were subjected to analysis of variance (ANOVA) test and its post hoc analysis, which proves that our model performs better than existing classifiers. Furthermore, a web app has been developed and deployed at https://stable-abppred.anvil.app to identify novel ABPs in protein sequences. Using this app, we identified novel ABPs in all the proteins of the Streptococcus phage T12 genome. These ABPs have shown amino acid similarities with experimentally tested antimicrobial peptides (AMPs) of other organisms. Hence, they could be chemically synthesized and experimentally validated for their activity against different bacteria. The model and app developed in this work can be further utilized to explore the protein diversity for identifying novel ABPs with broad-spectrum activity, especially against MDR bacterial pathogens.


Assuntos
Antibacterianos , Peptídeos , Sequência de Aminoácidos , Antibacterianos/farmacologia , Aprendizado de Máquina , Peptídeos/química , Proteínas
13.
Int J Med Microbiol ; 314: 151605, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38290401

RESUMO

The threat of multidrug-resistant organisms (MDROs) and antimicrobial resistance (AMR) are real and increasing every day. They affect not only healthcare systems but also communities, causing economic and public health concerns. Governments must take action to tackle AMR and prevent the spread of MDROs and regional hubs have a critical role to play in achieving this outcome. Furthermore, bacteria have no borders, consequently, cooperation networks should be extended between countries as a crucial strategy for achieving the success of infection control. Euregions, which are a specific form of cooperation between local authorities of two or more bordering European countries, can help solve common problems and improve the lives of people living on both sides of the border. Regional collaboration strategies can enhance infection control and build resilience against antimicrobial resistance. This review identifies risk factors and the correct approaches to infection prevention and control, including education and awareness programs for healthcare professionals, appropriate prescribing practices, and infection prevention control measures. These measures can help reduce the incidence of antimicrobial resistance in the region and save lives. It is therefore essential to take concrete actions and foster the creation of more effective regional and cross-border centers to ensure the success of infection control policies and the management of healthcare-associated infections. This work sheds light on the issue of MDRO infections within healthcare settings, while also acknowledging the crucial role of the One Health concept in understanding the broader context of these infections. By recognizing the interdependence of human and animal health and the environment, we can take constructive steps toward mitigating the risks of these infections and promoting better health outcomes for all.


Assuntos
Anti-Infecciosos , Infecção Hospitalar , Animais , Humanos , Infecção Hospitalar/microbiologia , Controle de Infecções , Europa (Continente)/epidemiologia , Fatores de Risco
14.
Int J Med Microbiol ; 314: 151611, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38309143

RESUMO

Numbers of infections with Neisseria gonorrhoeae are among the top three sexually transmitted infections (STI) worldwide. In addition, the emergence and spread of antimicrobial resistance (AMR) in Neisseria gonorrhoeae pose an important public-health issue. The integration of genomic, phenotypic and epidemiological data to monitor Neisseria gonorrhoeae fosters our understanding of the emergence and spread of AMR in Neisseria gonorrhoeae and helps to inform therapy guidelines and intervention strategies. Thus, the Gonococcal resistance surveillance (Go-Surv-AMR) was implemented at the Robert Koch Institute in Germany in 2021 to obtain molecular, phenotypic and epidemiological data on Neisseria gonorrhoeae isolated in Germany. Here, we describe the structure and aims of Go-Surv-AMR. Furthermore, we point out future directions of Go-Surv-AMR to improve the integrated genomic surveillance of Neisseria gonorrhoeae. In this context we discuss current and prospective sequencing approaches and the information derived from their application. Moreover, we highlight the importance of combining phenotypic and WGS data to monitor the evolution of AMR in Neisseria gonorrhoeae in Germany. The implementation and constant development of techniques and tools to improve the genomic surveillance of Neisseria gonorrhoeae will be important in coming years.


Assuntos
Gonorreia , Neisseria gonorrhoeae , Humanos , Neisseria gonorrhoeae/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Estudos Prospectivos , Farmacorresistência Bacteriana/genética , Testes de Sensibilidade Microbiana , Gonorreia/tratamento farmacológico , Gonorreia/epidemiologia , Alemanha/epidemiologia
15.
Appl Environ Microbiol ; 90(5): e0212823, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38572968

RESUMO

Escherichia coli is a promising subject for globally coordinated surveillance of antimicrobial resistance (AMR) in water environments due to its clinical relevance and widespread use as an indicator of fecal contamination. Cefotaxime-resistant E. coli was recently evaluated favorably for this purpose by the World Health Organization TriCycle Protocol, which specifies tryptone bile x-glucuronide (TBX) medium and incubation at 35°C. We assessed comparability with the U.S. Environmental Protection Agency-approved method for E. coli quantification, which uses membrane-thermotolerant E. coli (mTEC) agar and incubation at 44.5°C, in terms of recovery of E. coli and cefotaxime-resistant E. coli from wastewater influent and surface waters. Total E. coli concentrations in wastewater influent were 106-108 CFU/100 mL, while cefotaxime-resistant E. coli were ~100-fold lower. Total E. coli in surface waters were ~102 CFU/100 mL, and cefotaxime-resistant isolates were near the limit of detection (0.4 CFU/100 mL). Total and putative cefotaxime-resistant E. coli concentrations did not differ significantly between media or by incubation method; however, colonies isolated on mTEC were more frequently confirmed to species (97.1%) compared to those from TBX (92.5%). Incubation in a water bath at 44.5°C significantly decreased non-specific background growth and improved confirmation frequency on both media (97.4%) compared to incubation at 35°C (92.3%). This study helps to advance globally coordinated AMR in water environments and suggests that the TriCycle Protocol is adaptable to other standard methods that may be required in different locales, while also offering a means to improve specificity by decreasing the frequency of false-positive identification of cefotaxime-resistant E. coli by modifying incubation conditions.IMPORTANCEAs antibiotic-resistant bacteria in water environments are increasingly recognized as contributors to the global antibiotic resistance crisis, the need for a monitoring subject that captures antibiotic resistance trends on a global scale increases. The World Health Organization TriCycle Protocol proposes the use of cefotaxime-resistant Escherichia coli isolated on tryptone bile x-glucuronide agar. The U.S. Environmental Protection Agency (USEPA) criteria for safe recreational waters also use E. coli as an indicator but specify the use of mTEC agar at a higher incubation temperature (44.5°C vs 35°C). We assessed the comparability of these methods for isolating total and cefotaxime-resistant E. coli, finding overall good agreement and performance, but significantly higher specificity toward E. coli selection with the use of the USEPA incubation protocol and mTEC agar. This study is the first to directly compare these methods and provides evidence that the methods may be used interchangeably for global surveillance of antibiotic resistance in the environment.


Assuntos
Antibacterianos , Cefotaxima , Escherichia coli , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Escherichia coli/genética , Cefotaxima/farmacologia , Antibacterianos/farmacologia , Microbiologia da Água , Monitoramento Ambiental/métodos , Farmacorresistência Bacteriana , Águas Residuárias/microbiologia , Meios de Cultura/química
16.
BMC Microbiol ; 24(1): 103, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38539119

RESUMO

Vancomycin-resistant enterococci (VRE) are major opportunistic pathogens and the causative agents of serious diseases, such as urinary tract infections and endocarditis. VRE strains mainly include species of Enterococcus faecium and E. faecalis which can colonise the gastrointestinal tract (GIT) of patients and, following growth and persistence in the gut, can transfer to blood resulting in systemic dissemination in the body. Advancements in genomics have revealed that hospital-associated VRE strains are characterised by increased numbers of mobile genetic elements, higher numbers of antibiotic resistance genes and often lack active CRISPR-Cas systems. Additionally, comparative genomics have increased our understanding of dissemination routes among patients and healthcare workers. Since the efficiency of currently available antibiotics is rapidly declining, new measures to control infection and dissemination of these persistent pathogens are urgently needed. These approaches include combinatory administration of antibiotics, strengthening colonisation resistance of the gut microbiota to reduce VRE proliferation through commensals or probiotic bacteria, or switching to non-antibiotic bacterial killers, such as bacteriophages or bacteriocins. In this review, we discuss the current knowledge of the genomics of VRE isolates and state-of-the-art therapeutic advances against VRE infections.


Assuntos
Enterococcus faecium , Microbioma Gastrointestinal , Infecções por Bactérias Gram-Positivas , Enterococos Resistentes à Vancomicina , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Enterococos Resistentes à Vancomicina/genética , Enterococcus faecium/genética , Microbioma Gastrointestinal/genética , Genômica , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/microbiologia , Testes de Sensibilidade Microbiana
17.
Crit Rev Microbiol ; 50(2): 196-211, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38400715

RESUMO

Antimicrobial resistance (AMR) in clinically priority pathogensis now a major threat to public health worldwide. Phages are bacterial parasites that efficiently infect or kill specific strains and represent the most abundant biological entities on earth, showing great attraction as potential antibacterial therapeutics in combating AMR. This review provides a summary of phage-inspired strategies to combat AMR. We firstly cover the phage diversity, and then explain the biological principles of phage therapy that support the use of phages in the post-antimicrobial era. Furthermore, we state the versatility methods of phage therapy both from direct access as well as collateral access. Among the direct access approaches, we discuss the use of phage cocktail therapy, phage-encoded endolysins and the bioengineering for function improvement of used phages or endolysins. On the other hand, we introduce the collateral access, including the phages antimicrobial immunity combined therapy and phage-based novel antibacterial mimic molecules. Nowadays, more and more talented and enthusiastic scientist, doctors, pharmacists, media, authorities, and industry are promoting the progress of phage therapy, and proposed more phages-inspired strategy to make them more tractable to combat AMR and benefit more people, more animal and diverse environment in "one health" framework.


Assuntos
Bacteriófagos , Animais , Humanos , Bactérias/genética , Farmacorresistência Bacteriana , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
18.
Crit Rev Microbiol ; : 1-40, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38425122

RESUMO

Antibiotics have remained the cornerstone for the treatment of bacterial infections ever since their discovery in the twentieth century. The uproar over antibiotic resistance among bacteria arising from genome plasticity and biofilm development has rendered current antibiotic therapies ineffective, urging the development of innovative therapeutic approaches. The development of antibiotic resistance among bacteria has further heightened the clinical failure of antibiotic therapy, which is often linked to its low bioavailability, side effects, and poor penetration and accumulation at the site of infection. In this review, we highlight the potential use of siderophores, antibodies, cell-penetrating peptides, antimicrobial peptides, bacteriophages, and nanoparticles to smuggle antibiotics across impermeable biological membranes to achieve therapeutically relevant concentrations of antibiotics and combat antimicrobial resistance (AMR). We will discuss the general mechanisms via which each delivery system functions and how it can be tailored to deliver antibiotics against the paradigm of mechanisms underlying antibiotic resistance.

19.
Microb Pathog ; 192: 106722, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38815775

RESUMO

The escalating threat of antimicrobial resistance (AMR) poses a grave concern to global public health, exacerbated by the alarming shortage of effective antibiotics in the pipeline. Biofilms, intricate populations of bacteria encased in self-produced matrices, pose a significant challenge to treatment, as they enhance resistance to antibiotics and contribute to the persistence of organisms. Amid these challenges, nanotechnology emerges as a promising domain in the fight against biofilms. Nanomaterials, with their unique properties at the nanoscale, offer innovative antibacterial modalities not present in traditional defensive mechanisms. This comprehensive review focuses on the potential of nanotechnology in combating biofilms, focusing on green-synthesized nanoparticles and their associated anti-biofilm potential. The review encompasses various aspects of nanoparticle-mediated biofilm inhibition, including mechanisms of action. The diverse mechanisms of action of green-synthesized nanoparticles offer valuable insights into their potential applications in addressing AMR and improving treatment outcomes, highlighting novel strategies in the ongoing battle against infectious diseases.


Assuntos
Antibacterianos , Bactérias , Biofilmes , Nanopartículas , Nanoestruturas , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Virulência/efeitos dos fármacos , Nanoestruturas/química , Nanopartículas/química , Humanos , Nanotecnologia , Farmacorresistência Bacteriana
20.
Respir Res ; 25(1): 262, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951782

RESUMO

BACKGROUND: Donor-specific antibodies (DSAs) are common following lung transplantation (LuTx), yet their role in graft damage is inconclusive. Mean fluorescent intensity (MFI) is the main read-out of DSA diagnostics; however its value is often disregarded when analyzing unwanted post-transplant outcomes such as graft loss or chronic lung allograft dysfunction (CLAD). Here we aim to evaluate an MFI stratification method in these outcomes. METHODS: A cohort of 87 LuTx recipients has been analyzed, in which a cutoff of 8000 MFI has been determined for high MFI based on clinically relevant data. Accordingly, recipients were divided into DSA-negative, DSA-low and DSA-high subgroups. Both graft survival and CLAD-free survival were evaluated. Among factors that may contribute to DSA development we analyzed Pseudomonas aeruginosa (P. aeruginosa) infection in bronchoalveolar lavage (BAL) specimens. RESULTS: High MFI DSAs contributed to clinical antibody-mediated rejection (AMR) and were associated with significantly worse graft (HR: 5.77, p < 0.0001) and CLAD-free survival (HR: 6.47, p = 0.019) compared to low or negative MFI DSA levels. Analysis of BAL specimens revealed a strong correlation between DSA status, P. aeruginosa infection and BAL neutrophilia. DSA-high status and clinical AMR were both independent prognosticators for decreased graft and CLAD-free survival in our multivariate Cox-regression models, whereas BAL neutrophilia was associated with worse graft survival. CONCLUSIONS: P. aeruginosa infection rates are elevated in recipients with a strong DSA response. Our results indicate that the simultaneous interpretation of MFI values and BAL neutrophilia is a feasible approach for risk evaluation and may help clinicians when to initiate DSA desensitization therapy, as early intervention could improve prognosis.


Assuntos
Rejeição de Enxerto , Transplante de Pulmão , Infecções por Pseudomonas , Pseudomonas aeruginosa , Transplante de Pulmão/efeitos adversos , Transplante de Pulmão/mortalidade , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Infecções por Pseudomonas/imunologia , Infecções por Pseudomonas/diagnóstico , Infecções por Pseudomonas/mortalidade , Adulto , Pseudomonas aeruginosa/imunologia , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/diagnóstico , Doadores de Tecidos , Estudos Retrospectivos , Sobrevivência de Enxerto , Estudos de Coortes , Isoanticorpos/sangue , Idoso
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