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1.
J R Soc Med ; 117(1): 11-23, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37351911

RESUMEN

OBJECTIVES: To understand severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission risks, perceived risks and the feasibility of risk mitigations from experimental mass cultural events before coronavirus disease 2019 (COVID-19) restrictions were lifted. DESIGN: Prospective, population-wide observational study. SETTING: Four events (two nightclubs, an outdoor music festival and a business conference) open to Liverpool City Region UK residents, requiring a negative lateral flow test (LFT) within the 36 h before the event, but not requiring social distancing or face-coverings. PARTICIPANTS: A total of 12,256 individuals attending one or more events between 28 April and 2 May 2021. MAIN OUTCOME MEASURES: SARS-CoV-2 infections detected using audience self-swabbed (5-7 days post-event) polymerase chain reaction (PCR) tests, with viral genomic analysis of cases, plus linked National Health Service COVID-19 testing data. Audience experiences were gathered via questionnaires, focus groups and social media. Indoor CO2 concentrations were monitored. RESULTS: A total of 12 PCR-positive cases (likely 4 index, 8 primary or secondary), 10 from the nightclubs. Two further cases had positive LFTs but no PCR. A total of 11,896 (97.1%) participants with scanned tickets were matched to a negative pre-event LFT: 4972 (40.6%) returned a PCR within a week. CO2 concentrations showed areas for improving ventilation at the nightclubs. Population infection rates were low, yet with a concurrent outbreak of >50 linked cases around a local swimming pool without equivalent risk mitigations. Audience anxiety was low and enjoyment high. CONCLUSIONS: We observed minor SARS-CoV-2 transmission and low perceived risks around events when prevalence was low and risk mitigations prominent. Partnership between audiences, event organisers and public health services, supported by information systems with real-time linked data, can improve health security for mass cultural events.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , SARS-CoV-2 , Prueba de COVID-19 , Dióxido de Carbono , Estudios Prospectivos , Medicina Estatal , Reino Unido/epidemiología
2.
Microbiol Resour Announc ; 12(9): e0016323, 2023 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-37504519

RESUMEN

The continued emergence and spread of antimicrobial resistance among pathogenic bacteria are ever-growing threats to health and economy. Here, we report the draft genomes for 45 Enterobacterales clinical isolates, including historical and contemporary drug-resistant organisms, obtained in Pakistan between 1998 and 2016: 5 Serratia, 3 Salmonella, 3 Enterobacter, and 34 Klebsiella.

3.
Front Microbiol ; 14: 1192097, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37455731

RESUMEN

Objectives: The study aim was to investigate multidrug-resistant (MDR) plasmids from a collection of 10 carbapenemase-producing Klebsiella pneumoniae clinical isolates identified within the same healthcare institution in Pakistan. Full characterization of the MDR plasmids including structure, typing characteristics, and AMR content as well as determination of their plasmid-based antimicrobial susceptibility profiles were carried out. Methods: Plasmids were isolated from 10 clinical isolates of Klebsiella pneumoniae, and from a corresponding set of Escherichia coli transconjugants, then sequenced using Nanopore/Illumina technology to generate plasmid hybrid assemblies. Full characterization of MDR plasmids, including determination of next generation sequencing (NGS)-based AMR profiles, plasmid incompatibility groups, and types, was carried out. The structure of MDR plasmids was analyzed using the Galileo AMR platform. For E. coli transconjugants, the NGS-based AMR profiles were compared to NGS-predicted AMR phenotypes and conventional broth microdilution (BMD) antimicrobial susceptibility testing (AST) results. Results: All carbapenemase-producing K. pneumoniae isolates (carrying either blaNDM-1, or/and blaOXA-48) carried multiple AMR plasmids encoding 34 antimicrobial resistance genes (ARGs) conferring resistance to antimicrobials from 6 different classes. The plasmid incompatibility groups and types identified were: IncC (types 1 and 3), IncFIA (type 26) IncFIB, IncFII (types K1, K2, K7, and K9), IncHI1B, and IncL. None of the blaNDM-1 and blaESBL-plasmids identified in this study were previously described. Most blaNDM-1-plasmids shared identical AMR regions suggesting potential genetic material/plasmid exchange between K. pneumoniae isolates of this collection. The majority of NGS-based AMR profiles from the E. coli transconjugants correlated well with both NGS-based predicted and conventional AST results. Conclusion: This study highlights the complexity and diversity of the plasmid-based genetic background of carbapenemase-producing clinical isolates from Pakistan. This study emphasizes the need for characterization of MDR plasmids to determine their complete molecular background and monitor AMR through plasmid transmission between multi-resistant bacterial pathogens.

4.
ACS Infect Dis ; 9(1): 122-139, 2023 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-36475632

RESUMEN

CXCL10 is a pro-inflammatory chemokine produced by the host in response to microbial infection. In addition to canonical, receptor-dependent actions affecting immune-cell migration and activation, CXCL10 has also been found to directly kill a broad range of pathogenic bacteria. Prior investigations suggest that the bactericidal effects of CXCL10 occur through two distinct pathways that compromise the cell envelope. These observations raise the intriguing notion that CXCL10 features a separable pair of antimicrobial domains. Herein, we affirm this possibility through peptide-based mapping and structure/function analyses, which demonstrate that discrete peptides derived from the N- and C-terminal regions of CXCL10 mediate bacterial killing. The N-terminal derivative, peptide P1, exhibited marked antimicrobial activity against Bacillus anthracis vegetative bacilli and spores, as well as antibiotic-resistant clinical isolates of Klebsiella pneumoniae, Acinetobacter baumannii, Enterococcus faecium, and Staphylococcus aureus, among others. At bactericidal concentrations, peptide P1 had a minimal degree of chemotactic activity, but did not cause red blood cell hemolysis or cytotoxic effects against primary human cells. The C-terminal derivative, peptide P9, exhibited antimicrobial effects, but only against Gram-negative bacteria in low-salt medium─conditions under which the peptide can adopt an α-helical conformation. The introduction of a hydrocarbon staple induced and stabilized α-helicity; accordingly, stapled peptide P9 displayed significantly improved bactericidal effects against both Gram-positive and Gram-negative bacteria in media containing physiologic levels of salt. Together, our findings identify and characterize the antimicrobial regions of CXCL10 and functionalize these novel determinants as discrete peptides with potential therapeutic utility against difficult-to-treat pathogens.


Asunto(s)
Antibacterianos , Antiinfecciosos , Humanos , Antibacterianos/farmacología , Antibacterianos/metabolismo , Quimiocina CXCL10/metabolismo , Quimiocina CXCL10/farmacología , Bacterias Gramnegativas , Bacterias Grampositivas , Antiinfecciosos/farmacología
5.
Eye (Lond) ; 37(5): 907-924, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-35941183

RESUMEN

Uveal melanoma (UM) survivors can experience significant emotional distress, although the factors underpinning this are poorly understood. Systematic reviews of distress in UM only include cross-sectional studies, thereby limiting our understanding of causal factors. This review identified prospective clinical, demographic, social and psychological predictors of distress in UM survivors. A systematic search of the literature for English language prospective studies was conducted. Thirteen papers, reporting data from seven unique datasets were included in a narrative synthesis of the results. Younger age (3 studies from 3 datasets), physical health (including visual impairment, ocular symptoms, and other UM-related factors; 3 studies from 3 datasets), and psychological factors (mainly baseline distress; 3 studies from 3 datasets and worry about recurrence; 2 studies from 2 datasets), significantly predicted distress. There was no consistent evidence for other demographic, clinical or social variables (significant in <50% of datasets). Generally, the quality of the papers was adequate. However, attrition rates were high or not reported in over half of the included studies. The findings of this review emphasise the importance of attempts to prevent and recognise distress immediately post-diagnosis of UM. Particular focus should be given to younger patients, those with physical and psychological health difficulties at the time of diagnosis, and those who develop adverse treatment symptoms during survivorship. More research into potential social and psychological variables and their role in predicting distress in survivors is recommended.


Asunto(s)
Supervivientes de Cáncer , Distrés Psicológico , Humanos , Estudios Prospectivos , Supervivientes de Cáncer/psicología , Estrés Psicológico/etiología , Estudios Transversales , Calidad de Vida/psicología
6.
Nurs Adm Q ; 46(2): 167-176, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35239587

RESUMEN

The coronavirus disease-2019 (COVID-19) pandemic posed unprecedented challenges for health care organizations, schools of nursing, and surrounding communities. Health care organizations encountered rapidly changing guidelines and shortages in the health care workforce and critical medical supplies. Schools of nursing were responding to abrupt suspensions of clinical placements, uncertainties about the transmission of the novel virus, and shortages of personal protective equipment. Despite these challenges, health care organizations and schools of nursing were laser-focused on the need to ensure a competent nursing workforce and timely pandemic response efforts. Thus, an innovative academic-practice collaboration between Yale New Haven Hospital and Quinnipiac University School of Nursing was developed to meet community vaccination and testing needs. The partnership was designed to provide undergraduate student nurses with valuable community health clinical hours during the spring 2021 semester while meeting the hospital's needs for supporting the COVID-19 vaccine clinics and testing sites. The positive outcomes of the collaboration and specific lessons learned are discussed.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , COVID-19/epidemiología , COVID-19/prevención & control , Vacunas contra la COVID-19/uso terapéutico , Humanos , SARS-CoV-2 , Universidades , Vacunación
7.
Microbiol Resour Announc ; 9(20)2020 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-32409526

RESUMEN

Infections in immunocompromised patients that are caused by extensively drug-resistant (XDR) Acinetobacter baumannii strains have been increasingly reported worldwide. In particular, carbapenem-resistant A. baumannii strains are a prominent cause of health care-associated infections. Here, we report draft genome assemblies for two clinical XDR A. baumannii isolates obtained from hospitalized patients in Pakistan.

8.
Microbiol Resour Announc ; 8(30)2019 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-31346012

RESUMEN

Shigella spp. are the most common cause of dysentery in developing countries and the second leading cause of diarrheal deaths worldwide. Multidrug-resistant (MDR) Shigella spp. are a serious threat to global health. Herein, we report draft genome sequences for three MDR Shigella isolates from Pakistan, two Shigella flexneri isolates and one Shigella sonnei isolate.

9.
PLoS One ; 13(6): e0198526, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29883490

RESUMEN

The emergence and dissemination of carbapenemases, bacterial enzymes able to inactivate most ß-lactam antibiotics, in Enterobacteriaceae is of increasing concern. The concurrent spread of resistance against colistin, an antibiotic of last resort, further compounds this challenge further. Whole-genome sequencing (WGS) can play a significant role in the rapid and accurate detection/characterization of existing and emergent resistance determinants, an essential aspect of public health surveillance and response activities to combat the spread of antimicrobial resistant bacteria. In the current study, WGS data was used to characterize the genomic content of antimicrobial resistance genes, including those encoding carbapenemases, in 10 multidrug-resistant Klebsiella pneumoniae isolates from Pakistan. These clinical isolates represented five sequence types: ST11 (n = 3 isolates), ST14 (n = 3), ST15 (n = 1), ST101 (n = 2), and ST307 (n = 1). Resistance profiles against 25 clinically-relevant antimicrobials were determined by broth microdilution; resistant phenotypes were observed for at least 15 of the 25 antibiotics tested in all isolates except one. Specifically, 8/10 isolates were carbapenem-resistant and 7/10 isolates were colistin-resistant. The blaNDM-1 and blaOXA-48 carbapenemase genes were present in 7/10 and 5/10 isolates, respectively; including 2 isolates carrying both genes. No plasmid-mediated determinants for colistin resistance (e.g. mcr) were detected, but disruptions and mutations in chromosomal loci (i.e. mgrB and pmrB) previously reported to confer colistin resistance were observed. A blaOXA-48-carrying IncL/M-type plasmid was found in all blaOXA-48-positive isolates. The application of WGS to molecular epidemiology and surveillance studies, as exemplified here, will provide both a more complete understanding of the global distribution of MDR isolates and a robust surveillance tool useful for detecting emerging threats to public health.


Asunto(s)
Antibacterianos/farmacología , Carbapenémicos/farmacología , Colistina/farmacología , Infecciones por Klebsiella/diagnóstico , Klebsiella pneumoniae/efectos de los fármacos , Proteínas Bacterianas/genética , Enzimas de Restricción del ADN/genética , ADN Bacteriano/química , ADN Bacteriano/aislamiento & purificación , ADN Bacteriano/metabolismo , Farmacorresistencia Bacteriana/genética , Humanos , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Tipificación Molecular , Plásmidos/genética , Plásmidos/metabolismo , Secuenciación Completa del Genoma
10.
mBio ; 8(6)2017 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-29138303

RESUMEN

The continued rise and spread of antimicrobial resistance among bacterial pathogens pose a serious challenge to global health. Countering antimicrobial-resistant pathogens requires a multifaceted effort that includes the discovery of novel therapeutic approaches. Here, we establish the capacity of the human CXC chemokines CXCL9 and CXCL10 to kill multidrug-resistant Gram-negative bacteria, including New Delhi metallo-beta-lactamase-1-producing Klebsiella pneumoniae and colistin-resistant members of the family Enterobacteriaceae that harbor the mobile colistin resistance protein MCR-1 and thus possess phosphoethanolamine-modified lipid A. Colistin-resistant K. pneumoniae isolates affected by genetic mutation of the PmrA/PmrB two-component system, a chromosomally encoded regulator of lipopolysaccharide modification, and containing 4-amino-4-deoxy-l-arabinose-modified lipid A were also found to be susceptible to chemokine-mediated antimicrobial activity. However, loss of PhoP/PhoQ autoregulatory control, caused by disruption of the gene encoding the negative regulator MgrB, limited the bactericidal effects of CXCL9 and CXCL10 in a variable, strain-specific manner. Cumulatively, these findings provide mechanistic insight into chemokine-mediated antimicrobial activity, highlight disparities amongst determinants of colistin resistance, and suggest that chemokine-mediated bactericidal effects merit additional investigation as a therapeutic avenue for treating infections caused by multidrug-resistant pathogens.IMPORTANCE As bacterial pathogens become resistant to multiple antibiotics, the infections they cause become increasingly difficult to treat. Carbapenem antibiotics provide an essential clinical barrier against multidrug-resistant bacteria; however, the dissemination of bacterial enzymes capable of inactivating carbapenems threatens the utility of these important antibiotics. Compounding this concern is the global spread of bacteria invulnerable to colistin, a polymyxin antibiotic considered to be a last line of defense against carbapenem-resistant pathogens. As the effectiveness of existing antibiotics erodes, it is critical to develop innovative antimicrobial therapies. To this end, we demonstrate that the chemokines CXCL9 and CXCL10 kill the most concerning carbapenem- and colistin-resistant pathogens. Our findings provide a unique and timely foundation for therapeutic strategies capable of countering antibiotic-resistant "superbugs."


Asunto(s)
Antibacterianos/metabolismo , Quimiocina CXCL10/metabolismo , Quimiocina CXCL9/metabolismo , Enterobacteriaceae/efectos de los fármacos , Viabilidad Microbiana/efectos de los fármacos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Enterobacteriaceae/fisiología , Humanos
11.
Genome Announc ; 4(6)2016 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-27979956

RESUMEN

The emergence and spread of colistin resistance among multidrug-resistant (MDR) Klebsiella pneumoniae represent a critical threat to global health. Here, we report the complete genome sequences of 10 MDR, colistin-susceptible and -resistant K. pneumoniae clinical isolates obtained in Pakistan between 2010 and 2013.

12.
Infect Immun ; 84(1): 320-8, 2016 01.
Artículo en Inglés | MEDLINE | ID: mdl-26553462

RESUMEN

Chemokines are best recognized for their role within the innate immune system as chemotactic cytokines, signaling and recruiting host immune cells to sites of infection. Certain chemokines, such as CXCL10, have been found to play an additional role in innate immunity, mediating CXCR3-independent killing of a diverse array of pathogenic microorganisms. While this is still not clearly understood, elucidating the mechanisms underlying chemokine-mediated antimicrobial activity may facilitate the development of novel therapeutic strategies effective against antibiotic-resistant Gram-negative pathogens. Here, we show that CXCL10 exerts antibacterial effects on clinical and laboratory strains of Escherichia coli and report that disruption of pyruvate dehydrogenase complex (PDHc), which converts pyruvate to acetyl coenzyme A, enables E. coli to resist these antimicrobial effects. Through generation and screening of a transposon mutant library, we identified two mutants with increased resistance to CXCL10, both with unique disruptions of the gene encoding the E1 subunit of PDHc, aceE. Resistance to CXCL10 also occurred following deletion of either aceF or lpdA, genes that encode the remaining two subunits of PDHc. Although PDHc resides within the bacterial cytosol, electron microscopy revealed localization of immunogold-labeled CXCL10 to the bacterial cell surface in both the E. coli parent and aceE deletion mutant strains. Taken together, our findings suggest that while CXCL10 interacts with an as-yet-unidentified component on the cell surface, PDHc is an important mediator of killing by CXCL10. To our knowledge, this is the first description of PDHc as a key bacterial component involved in the antibacterial effect of a chemokine.


Asunto(s)
Antibacterianos/metabolismo , Proteínas de la Membrana Bacteriana Externa/metabolismo , Quimiocina CXCL10/metabolismo , Inmunidad Innata/inmunología , Piruvato Deshidrogenasa (Lipoamida)/metabolismo , Sitios de Unión , Dihidrolipoamida Deshidrogenasa/genética , Acetiltransferasa de Residuos Dihidrolipoil-Lisina/genética , Farmacorresistencia Bacteriana Múltiple/genética , Escherichia coli , Técnicas de Inactivación de Genes , Humanos , Unión Proteica , Piruvato Deshidrogenasa (Lipoamida)/genética
13.
Proc Natl Acad Sci U S A ; 108(41): 17159-64, 2011 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-21949405

RESUMEN

Chemokines are a family of chemotactic cytokines that function in host defense by orchestrating cellular movement during infection. In addition to this function, many chemokines have also been found to mediate the direct killing of a range of pathogenic microorganisms through an as-yet-undefined mechanism. As an understanding of the molecular mechanism and microbial targets of chemokine-mediated antimicrobial activity is likely to lead to the identification of unique, broad-spectrum therapeutic targets for effectively treating infection, we sought to investigate the mechanism by which the chemokine CXCL10 mediates bactericidal activity against the Gram-positive bacterium Bacillus anthracis, the causative agent of anthrax. Here, we report that disruption of the gene ftsX, which encodes the transmembrane domain of a putative ATP-binding cassette transporter, affords resistance to CXCL10-mediated antimicrobial effects against vegetative B. anthracis bacilli. Furthermore, we demonstrate that in the absence of FtsX, CXCL10 is unable to localize to its presumed site of action at the bacterial cell membrane, suggesting that chemokines interact with specific, identifiable bacterial components to mediate direct microbial killing. These findings provide unique insight into the mechanism of CXCL10-mediated bactericidal activity and establish, to our knowledge, the first description of a bacterial component critically involved in the ability of host chemokines to target and kill a bacterial pathogen. These observations also support the notion of chemokine-mediated antimicrobial activity as an important foundation for the development of innovative therapeutic strategies for treating infections caused by pathogenic, potentially multidrug-resistant microorganisms.


Asunto(s)
Bacillus anthracis/inmunología , Proteínas Bacterianas/inmunología , Proteínas de Ciclo Celular/inmunología , Quimiocinas CXC/fisiología , Animales , Antiinfecciosos/farmacología , Bacillus anthracis/efectos de los fármacos , Bacillus anthracis/genética , Bacillus anthracis/ultraestructura , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Membrana Celular/inmunología , Membrana Celular/ultraestructura , Quimiocina CXCL10/farmacología , Quimiocina CXCL10/fisiología , Quimiocina CXCL9/farmacología , Quimiocina CXCL9/fisiología , Farmacorresistencia Microbiana/genética , Eliminación de Gen , Genes Bacterianos , Prueba de Complementación Genética , Interacciones Huésped-Patógeno/inmunología , Humanos , Ratones , Microscopía Electrónica de Transmisión , Mutación , Esporas Bacterianas/efectos de los fármacos , Esporas Bacterianas/inmunología
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