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2.
Antimicrob Resist Infect Control ; 13(1): 75, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38992708

RESUMEN

BACKGROUND: Nasal carriage of Staphylococcus aureus is a risk factor for surgical site infections (SSI) in orthopaedic surgery. The efficacy of decolonisation for S. aureus on reducing the risk of SSI is uncertain in this speciality. The objective was to evaluate the impact of a nasal screening strategy of S. aureus and targeted decolonisation on the risk of S. aureus SSI. METHODS: A retrospective pre-post and here-elsewhere study was conducted between January 2014 and June 2020 in 2 adult orthopaedic surgical sites (North and South) of a French university hospital. Decolonisation with Mupirocin and Chlorhexidine was conducted in S. aureus carriers starting February 2017 in the South site (intervention group). Scheduled surgical procedures for hip, knee arthroplasties, and osteosyntheses were included and monitored for one year. The rates of S. aureus SSI in the intervention group were compared to a historical control group (South site) and a North control group. The risk factors for S. aureus SSI were analysed by logistic regression. RESULTS: A total of 5,348 surgical procedures was included, 100 SSI of which 30 monomicrobial S. aureus SSI were identified. The preoperative screening result was available for 60% (1,382/2,305) of the intervention group patients. Among these screenings, 25.3% (349/1,382) were positive for S. aureus and the efficacy of the decolonisation was 91.6% (98/107). The rate of S. aureus SSI in the intervention group (0.3%, 7/2,305) was not significantly different from the historical control group (0.5%, 9/1926) but differed significantly from the North control group (1.3%, 14/1,117). After adjustment, the risk factors of S. aureus SSI occurrence were the body mass index (ORaper unit, 1.05; 95%CI, 1.0-1.1), the Charlson comorbidity index (ORaper point, 1.34; 95%CI, 1.0-1.8) and operative time (ORaper minute, 1.01; 95%CI, 1.00-1.02). Having benefited from S. aureus screening/decolonisation was a protective factor (ORa, 0.24; 95%CI, 0.08-0.73). CONCLUSIONS: Despite the low number of SSI, nasal screening and targeted decolonisation of S. aureus were associated with a reduction in S. aureus SSI.


Asunto(s)
Antibacterianos , Clorhexidina , Mupirocina , Procedimientos Ortopédicos , Infecciones Estafilocócicas , Staphylococcus aureus , Infección de la Herida Quirúrgica , Mupirocina/administración & dosificación , Mupirocina/uso terapéutico , Clorhexidina/uso terapéutico , Clorhexidina/administración & dosificación , Humanos , Infección de la Herida Quirúrgica/prevención & control , Estudios Retrospectivos , Infecciones Estafilocócicas/prevención & control , Femenino , Masculino , Staphylococcus aureus/efectos de los fármacos , Persona de Mediana Edad , Anciano , Procedimientos Ortopédicos/efectos adversos , Factores de Riesgo , Antibacterianos/uso terapéutico , Antibacterianos/administración & dosificación , Cuidados Preoperatorios , Portador Sano/tratamiento farmacológico , Tamizaje Masivo , Francia
3.
ACS Nano ; 18(26): 17086-17099, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38952327

RESUMEN

Traditional external field-assisted therapies, e.g., microwave (MW) therapy and phototherapy, cannot effectively and minimally damage eliminate deep-seated infection, owing to the poor penetrability of light and low reactive oxygen species (ROS) stimulation capability of MW. Herein, an implantable and wireless-powered therapeutic platform (CNT-FeTHQ-TS), in which external MW can be converted into internal light via MW wireless-powered light-emitting chips, is designed to eradicate deep-seated tissue infections by MW-induced deep-seated photodynamic therapy. In application, CNT-FeTHQ-TS is implanted at internal lesions, and the chip emits light under external MW irradiation. Subsequently, CNT-FeTHQ coating in the platform can respond to both MW and light simultaneously to generate ROS and MW-hyperthermia for rapid and precise sterilization at focus. Importantly, MW also improves the photodynamic performance of CNT-FeTHQ by introducing vacancies in FeTHQ to facilitate the photoexcitation process and changing the spin state of electrons to inhibit the complexation of photogenerated electron-hole pairs, which were confirmed by simulation calculations and in situ MW-irradiated photoluminescence experiments. In vivo, CNT-FeTHQ-TS can effectively cure mice with Staphylococcus aureus infection in dorsal subcutaneous tissue. This work overcomes the key clinical limitations of safe energy transmission and conversion for treating deep-seated infections.


Asunto(s)
Microondas , Fotoquimioterapia , Animales , Ratones , Especies Reactivas de Oxígeno/metabolismo , Tecnología Inalámbrica , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/química , Luz , Staphylococcus aureus/efectos de los fármacos , Infecciones Estafilocócicas/tratamiento farmacológico , Ratones Endogámicos BALB C , Antibacterianos/farmacología , Antibacterianos/química
4.
Methods Mol Biol ; 2833: 1-10, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38949695

RESUMEN

There is an increasing need for new treatment regimens to combat antibiotic-resistant strains of bacteria. Staphylococcus aureus is a clinically important, opportunist pathogen that has developed resistance to a range of antibiotics. The zebrafish larval model of systemic disease has been increasingly utilized to elucidate S. aureus virulence mechanisms and host-pathogen interactions. Here, we outline how this model can be used to investigate the effects of different antibiotics alone and in combination against S. aureus.


Asunto(s)
Antibacterianos , Modelos Animales de Enfermedad , Larva , Infecciones Estafilocócicas , Staphylococcus aureus , Pez Cebra , Animales , Pez Cebra/microbiología , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Staphylococcus aureus/efectos de los fármacos , Larva/microbiología , Larva/efectos de los fármacos , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Quimioterapia Combinada , Interacciones Huésped-Patógeno/efectos de los fármacos , Pruebas de Sensibilidad Microbiana
5.
Int J Mol Sci ; 25(13)2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-39000557

RESUMEN

The effects of intestinal microflora on extraintestinal immune response by intestinal cytokines and metabolites have been documented, but whether intestinal microbes stimulate serum antibody generation is unknown. Here, serum antibodies against 69 outer membrane proteins of Escherichia coli, a dominant bacterium in the human intestine, are detected in 141 healthy individuals of varying ages. Antibodies against E. coli outer membrane proteins are determined in all serum samples tested, and frequencies of antibodies to five outer membrane proteins (OmpA, OmpX, TsX, HlpA, and FepA) are close to 100%. Serum antibodies against E. coli outer membrane proteins are further validated by Western blot and bacterial pull-down. Moreover, the present study shows that OstA, HlpA, Tsx, NlpB, OmpC, YfcU, and OmpA provide specific immune protection against pathogenic E. coli, while HlpA and OmpA also exhibit cross-protection against Staphylococcus aureus infection. These finding indicate that intestinal E. coli activate extraintestinal antibody responses and provide anti-infective immunity.


Asunto(s)
Anticuerpos Antibacterianos , Proteínas de la Membrana Bacteriana Externa , Escherichia coli , Humanos , Escherichia coli/inmunología , Anticuerpos Antibacterianos/inmunología , Anticuerpos Antibacterianos/sangre , Proteínas de la Membrana Bacteriana Externa/inmunología , Adulto , Femenino , Staphylococcus aureus/inmunología , Masculino , Formación de Anticuerpos/inmunología , Persona de Mediana Edad , Proteínas de Escherichia coli/inmunología , Adulto Joven , Anciano , Infecciones Estafilocócicas/inmunología , Infecciones Estafilocócicas/microbiología , Adolescente , Infecciones por Escherichia coli/inmunología , Infecciones por Escherichia coli/microbiología
6.
Int J Mol Sci ; 25(13)2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-39000566

RESUMEN

Staphylococcal toxic shock syndrome (STSS) is a rare, yet potentially fatal disease caused by Staphylococcus aureus (S. aureus) enterotoxins, known as superantigens, which trigger an intense immune response. Our previous study demonstrated the protective effect of tofacitinib against murine toxin-induced shock and a beneficial effect against S. aureus sepsis. In the current study, we examined the effects of tofacitinib on T-cell response in peripheral blood using a mouse model of enterotoxin-induced shock. Our data revealed that tofacitinib suppresses the activation of both CD4+ and CD8+ T cells in peripheral blood. Furthermore, both gene and protein levels of Th1 cytokines were downregulated by tofacitinib treatment in mice with enterotoxin-induced shock. Importantly, we demonstrated that CD4+ cells, but not CD8+ cells, are pathogenic in mice with enterotoxin-induced shock. In conclusion, our findings suggest that tofacitinib treatment suppresses CD4+ T-cell activation and Th1 response, thereby aiding in protection against staphylococcal toxic shock in mice. This insight may guide the future development of novel therapies for STSS.


Asunto(s)
Linfocitos T CD4-Positivos , Activación de Linfocitos , Piperidinas , Pirimidinas , Choque Séptico , Infecciones Estafilocócicas , Células TH1 , Animales , Piperidinas/farmacología , Piperidinas/uso terapéutico , Células TH1/inmunología , Células TH1/efectos de los fármacos , Células TH1/metabolismo , Pirimidinas/farmacología , Pirimidinas/uso terapéutico , Choque Séptico/tratamiento farmacológico , Choque Séptico/inmunología , Choque Séptico/inducido químicamente , Ratones , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/metabolismo , Activación de Linfocitos/efectos de los fármacos , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/inmunología , Infecciones Estafilocócicas/microbiología , Enterotoxinas , Staphylococcus aureus/efectos de los fármacos , Citocinas/metabolismo , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Ratones Endogámicos C57BL , Femenino , Modelos Animales de Enfermedad , Superantígenos/inmunología
7.
Nat Commun ; 15(1): 5746, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38982056

RESUMEN

Candida albicans and Staphylococcus aureus are two commonly associated pathogens that cause nosocomial infections with high morbidity and mortality. Our prior and current work using a murine model of polymicrobial intra-abdominal infection (IAI) demonstrates that synergistic lethality is driven by Candida-induced upregulation of functional S. aureus α-toxin leading to polymicrobial sepsis and organ damage. In order to determine the candidal effector(s) mediating enhanced virulence, an unbiased screen of C. albicans transcription factor mutants was undertaken revealing that zcf13Δ/Δ fails to drive augmented α-toxin or lethal synergism during co-infection. A combination of transcriptional and phenotypic profiling approaches shows that ZCF13 regulates genes involved in pentose metabolism, including RBK1 and HGT7 that contribute to fungal ribose catabolism and uptake, respectively. Subsequent experiments reveal that ribose inhibits the staphylococcal agr quorum sensing system and concomitantly represses toxicity. Unlike wild-type C. albicans, zcf13Δ/Δ did not effectively utilize ribose during co-culture or co-infection leading to exogenous ribose accumulation and agr repression. Forced expression of RBK1 and HGT7 in the zcf13Δ/Δ mutant fully restores pathogenicity during co-infection. Collectively, our results detail the interwoven complexities of cross-kingdom interactions and highlight how intermicrobial metabolism impacts polymicrobial disease pathogenesis with devastating consequences for the host.


Asunto(s)
Candida albicans , Candidiasis , Coinfección , Proteínas Fúngicas , Infecciones Estafilocócicas , Staphylococcus aureus , Candida albicans/metabolismo , Candida albicans/patogenicidad , Candida albicans/genética , Animales , Coinfección/microbiología , Staphylococcus aureus/patogenicidad , Staphylococcus aureus/metabolismo , Staphylococcus aureus/genética , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/metabolismo , Candidiasis/microbiología , Ratones , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Infecciones Intraabdominales/microbiología , Femenino , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Percepción de Quorum/genética , Virulencia , Regulación Fúngica de la Expresión Génica , Modelos Animales de Enfermedad , Transactivadores/metabolismo , Transactivadores/genética
8.
World J Microbiol Biotechnol ; 40(9): 265, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38990361

RESUMEN

The increasing prevalence of infections related to methicillin-resistant Staphylococcus aureus (MRSA) necessitates the exploration of innovative therapeutic strategies that diverge from conventional antibiotic treatments. This is imperative to effectively combat resistance and manage these infections. The adoption of antivirulence strategies has emerged as a particularly promising avenue. This approach applies a heightened selective pressure on pathogens, thereby diminishing the likelihood of bacteria evolving resistance to antibiotics. In our pursuit of novel therapeutics for treating MRSA infections, we have focused on agents that inhibit the virulence of S. aureus without impeding its growth, aiming to minimize the development of drug resistance. α-Hemolysin, a critical virulence factor encoded by the hla gene, is a cytotoxin that forms pores in host cell membranes and plays a pivotal role in the progression of disease during bacterial infections. Herein, we identified that norwogonin could effectively inhibit Hla production via targeting agrAC, a crucial protein in quorum sensing, resulting in dose-dependent inhibition of hemolytic activity without suppressing S. aureus growth. In vitro assays illustrated that norwogonin decreased the thermal stability of agrAC, providing evidence of interaction between norwogonin and agrAC. Meanwhile, norwogonin alleviated Hla-mediated A549 cell damage and reduced lactate dehydrogenase release. In vivo studies suggested that norwogonin treatment blocked the establishment of a mouse model of pneumonia caused by S. aureus USA300. Notably, norwogonin enhanced the antibacterial potency of oxacillin. In conclusion, norwogonin is a promising candidate for treating S. aureus infections, offering a novel alternative to traditional antibiotics by targeting virulence factors and enhancing the efficacy of existing treatments.


Asunto(s)
Antibacterianos , Proteínas Bacterianas , Proteínas Hemolisinas , Staphylococcus aureus Resistente a Meticilina , Factores de Virulencia , Animales , Femenino , Humanos , Ratones , Células A549 , Antibacterianos/farmacología , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Toxinas Bacterianas/metabolismo , Modelos Animales de Enfermedad , Proteínas Hemolisinas/metabolismo , Hemólisis/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Ratones Endogámicos BALB C , Percepción de Quorum/efectos de los fármacos , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Virulencia/efectos de los fármacos , Factores de Virulencia/metabolismo
10.
Nat Commun ; 15(1): 5583, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38961085

RESUMEN

The function of many bacterial processes depends on the formation of functional membrane microdomains (FMMs), which resemble the lipid rafts of eukaryotic cells. However, the mechanism and the biological function of these membrane microdomains remain unclear. Here, we show that FMMs in the pathogen methicillin-resistant Staphylococcus aureus (MRSA) are dedicated to confining and stabilizing proteins unfolded due to cellular stress. The FMM scaffold protein flotillin forms a clamp-shaped oligomer that holds unfolded proteins, stabilizing them and favoring their correct folding. This process does not impose a direct energy cost on the cell and is crucial to survival of ATP-depleted bacteria, and thus to pathogenesis. Consequently, FMM disassembling causes the accumulation of unfolded proteins, which compromise MRSA viability during infection and cause penicillin re-sensitization due to PBP2a unfolding. Thus, our results indicate that FMMs mediate ATP-independent stabilization of unfolded proteins, which is essential for bacterial viability during infection.


Asunto(s)
Proteínas Bacterianas , Microdominios de Membrana , Proteínas de la Membrana , Staphylococcus aureus Resistente a Meticilina , Proteínas de la Membrana/metabolismo , Microdominios de Membrana/metabolismo , Staphylococcus aureus Resistente a Meticilina/metabolismo , Proteínas Bacterianas/metabolismo , Desplegamiento Proteico , Adenosina Trifosfato/metabolismo , Proteínas de Unión a las Penicilinas/metabolismo , Proteínas de Unión a las Penicilinas/genética , Proteínas de Unión a las Penicilinas/química , Humanos , Estabilidad Proteica , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/metabolismo , Animales , Ratones
11.
Nat Commun ; 15(1): 5526, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38951499

RESUMEN

An international collection of Staphylococcus aureus of clonal complex (CC) 398 from diverse hosts spanning all continents and a 30 year-period is studied based on whole-genome sequencing (WGS) data. The collection consists of publicly available genomic data from 2994 strains and 134 recently sequenced Swiss methicillin-resistant S. aureus (MRSA) CC398 strains. A time-calibrated phylogeny reveals the presence of distinct phylogroups present in Asia, North and South America and Europe. European MRSA diverged from methicillin-susceptible S. aureus (MSSA) at the beginning of the 1950s. Two major European phylogroups (EP4 and EP5), which diverged approximately 1974, are the main drivers of MRSA CC398 spread in Europe. Within EP5, an emergent MRSA lineage spreading among the European horse population (EP5-Leq) diverged approximately 1996 from the pig lineage (EP5-Lpg), and also contains human-related strains. EP5-Leq is characterized by staphylococcal cassette chromosome mec (SCCmec) IVa and spa type t011 (CC398-IVa-t011), and EP5-Lpg by CC398-SCCmecVc-t011. The lineage-specific antibiotic resistance and virulence gene patterns are mostly mediated by the acquisition of mobile genetic elements like SCCmec, S. aureus Genomic Islands (SaGIs), prophages and transposons. Different combinations of virulence factors are present on S. aureus pathogenicity islands (SaPIs), and novel antimicrobial resistance gene containing elements are associated with certain lineages expanding in Europe. This WGS-based analysis reveals the actual evolutionary trajectory and epidemiological trend of the international MRSA CC398 population considering host, temporal, geographical and molecular factors. It provides a baseline for global WGS-based One-Health studies of adaptive evolution of MRSA CC398 as well as for local outbreak investigations.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Filogenia , Infecciones Estafilocócicas , Secuenciación Completa del Genoma , Animales , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/clasificación , Staphylococcus aureus Resistente a Meticilina/patogenicidad , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/epidemiología , Humanos , Europa (Continente)/epidemiología , Caballos/microbiología , Staphylococcus aureus/genética , Staphylococcus aureus/clasificación , Staphylococcus aureus/patogenicidad , Genoma Bacteriano , Factores de Virulencia/genética , Cromosomas Bacterianos/genética , Evolución Molecular , Porcinos
12.
Sci Transl Med ; 16(754): eadi6887, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38959328

RESUMEN

Virulent infectious agents such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and methicillin-resistant Staphylococcus aureus (MRSA) induce tissue damage that recruits neutrophils, monocyte, and macrophages, leading to T cell exhaustion, fibrosis, vascular leak, epithelial cell depletion, and fatal organ damage. Neutrophils, monocytes, and macrophages recruited to pathogen-infected lungs, including SARS-CoV-2-infected lungs, express phosphatidylinositol 3-kinase gamma (PI3Kγ), a signaling protein that coordinates both granulocyte and monocyte trafficking to diseased tissues and immune-suppressive, profibrotic transcription in myeloid cells. PI3Kγ deletion and inhibition with the clinical PI3Kγ inhibitor eganelisib promoted survival in models of infectious diseases, including SARS-CoV-2 and MRSA, by suppressing inflammation, vascular leak, organ damage, and cytokine storm. These results demonstrate essential roles for PI3Kγ in inflammatory lung disease and support the potential use of PI3Kγ inhibitors to suppress inflammation in severe infectious diseases.


Asunto(s)
COVID-19 , Fosfatidilinositol 3-Quinasa Clase Ib , Inflamación , SARS-CoV-2 , COVID-19/patología , Fosfatidilinositol 3-Quinasa Clase Ib/metabolismo , Animales , Inflamación/patología , Humanos , Tratamiento Farmacológico de COVID-19 , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Ratones , Pulmón/patología , Inhibidores de las Quinasa Fosfoinosítidos-3/farmacología , Inhibidores de las Quinasa Fosfoinosítidos-3/uso terapéutico , Síndrome de Liberación de Citoquinas/tratamiento farmacológico , Permeabilidad Capilar/efectos de los fármacos , Ratones Endogámicos C57BL , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/patología
13.
Microb Genom ; 10(7)2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38967541

RESUMEN

Outbreaks of methicillin-resistant Staphylococcus aureus (MRSA) are well described in the neonatal intensive care unit (NICU) setting. Genomics has revolutionized the investigation of such outbreaks; however, to date, this has largely been completed retrospectively and has typically relied on short-read platforms. In 2022, our laboratory established a prospective genomic surveillance system using Oxford Nanopore Technologies sequencing for rapid outbreak detection. Herein, using this system, we describe the detection and control of an outbreak of sequence-type (ST)97 MRSA in our NICU. The outbreak was identified 13 days after the first MRSA-positive culture and at a point where there were only two known cases. Ward screening rapidly defined the extent of the outbreak, with six other infants found to be colonized. There was minimal transmission once the outbreak had been detected and appropriate infection control measures had been instituted; only two further ST97 cases were detected, along with three unrelated non-ST97 MRSA cases. To contextualize the outbreak, core-genome single-nucleotide variants were identified for phylogenetic analysis after de novo assembly of nanopore data. Comparisons with global (n=45) and national surveillance (n=35) ST97 genomes revealed the stepwise evolution of methicillin resistance within this ST97 subset. A distinct cluster comprising nine of the ten ST97-IVa genomes from the NICU was identified, with strains from 2020 to 2022 national surveillance serving as outgroups to this cluster. One ST97-IVa genome presumed to be part of the outbreak formed an outgroup and was retrospectively excluded. A second phylogeny was created using Illumina sequencing, which considerably reduced the branch lengths of the NICU isolates on the phylogenetic tree. However, the overall tree topology and conclusions were unchanged, with the exception of the NICU outbreak cluster, where differences in branch lengths were observed. This analysis demonstrated the ability of a nanopore-only prospective genomic surveillance system to rapidly identify and contextualize an outbreak of MRSA in a NICU.


Asunto(s)
Brotes de Enfermedades , Unidades de Cuidado Intensivo Neonatal , Staphylococcus aureus Resistente a Meticilina , Secuenciación de Nanoporos , Filogenia , Infecciones Estafilocócicas , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Staphylococcus aureus Resistente a Meticilina/clasificación , Humanos , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/microbiología , Recién Nacido , Secuenciación de Nanoporos/métodos , Infección Hospitalaria/epidemiología , Infección Hospitalaria/microbiología , Estudios Prospectivos , Genoma Bacteriano , Polimorfismo de Nucleótido Simple , Femenino
14.
Sci Rep ; 14(1): 15472, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38969796

RESUMEN

This study evaluated the determinants of mortality and the T cell immune response in patients with persistent Staphylococcus aureus bacteremia (SAB). This was a prospective cohort study and patients with confirmed SAB were enrolled from 2008 to 2020. We compared clinical, microbiological, and genotypic features between surviving and deceased patients with persistent SAB. The concentrations of cytokines and the proportions of IFN-γ secreting CD4+ T cells were measured serially during the bacteremia period. Of the 1760 patients, 242 had persistent bacteremia (PB), and 49 PB patients died within 30 days. In the multivariate analysis, the APACHE II score and female sex were independently associated with 30 days mortality. The level of IL-10 was significantly increased in the plasma of patients with a high Pitt bacteremia score and those who died within 12 weeks from the index day. The proportion of IFN-γ-secreting CD4+ T cells were the highest just before the positive-to-negative conversion of blood cultures in patients with a low Pitt bacteremia score and those who survived for 12 weeks. The level of IL-10 is correlated with clinical outcomes in PB patients. IFN-γ secreting CD4+ T cells might play a pivotal role in SAB PB.


Asunto(s)
Bacteriemia , Linfocitos T CD4-Positivos , Infecciones Estafilocócicas , Staphylococcus aureus , Humanos , Masculino , Femenino , Bacteriemia/mortalidad , Bacteriemia/microbiología , Bacteriemia/inmunología , Linfocitos T CD4-Positivos/inmunología , Infecciones Estafilocócicas/mortalidad , Infecciones Estafilocócicas/inmunología , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/inmunología , Persona de Mediana Edad , Factores de Riesgo , Anciano , Estudios Prospectivos , Interferón gamma/sangre , Interferón gamma/metabolismo , Interleucina-10/sangre , Adulto , Citocinas/sangre , Citocinas/metabolismo
15.
BMC Microbiol ; 24(1): 246, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38970013

RESUMEN

Previous studies have shown that antimicrobial photodynamic inactivation (aPDI) can be strongly potentiated by the addition of the non-toxic inorganic salt, potassium iodide (KI). This approach was shown to apply to many different photosensitizers, including the xanthene dye Rose Bengal (RB) excited by green light (540 nm). Rose Bengal diacetate (RBDA) is a lipophilic RB derivative that is easily taken up by cells and hydrolyzed to produce an active photosensitizer. Because KI is not taken up by microbial cells, it was of interest to see if aPDI mediated by RBDA could also be potentiated by KI. The addition of 100 mM KI strongly potentiated the killing of Gram-positive methicillin-resistant Staphylocccus aureus, Gram-negative Eschericia coli, and fungal yeast Candida albicans when treated with RBDA (up to 15 µM) for 2 hours followed by green light (540 nm, 10 J/cm2). Both RBDA aPDI regimens (400 µM RBDA with or without 400 mM KI followed by 20 J/cm2 green light) accelerated the healing of MRSA-infected excisional wounds in diabetic mice, without damaging the host tissue.


Asunto(s)
Candida albicans , Staphylococcus aureus Resistente a Meticilina , Fármacos Fotosensibilizantes , Yoduro de Potasio , Rosa Bengala , Infecciones Estafilocócicas , Cicatrización de Heridas , Animales , Rosa Bengala/farmacología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Cicatrización de Heridas/efectos de los fármacos , Yoduro de Potasio/farmacología , Ratones , Candida albicans/efectos de los fármacos , Fármacos Fotosensibilizantes/farmacología , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Escherichia coli/efectos de los fármacos , Diabetes Mellitus Experimental/microbiología , Diabetes Mellitus Experimental/tratamiento farmacológico , Fotoquimioterapia/métodos , Sinergismo Farmacológico , Luz , Masculino
16.
JCI Insight ; 9(13)2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38973612

RESUMEN

Staphylococcus aureus is a major human pathogen. An effective anti-S. aureus vaccine remains elusive as the correlates of protection are ill-defined. Targeting specific T cell populations is an important strategy for improving anti-S. aureus vaccine efficacy. Potential bottlenecks that remain are S. aureus-induced immunosuppression and the impact this might have on vaccine-induced immunity. S. aureus induces IL-10, which impedes effector T cell responses, facilitating persistence during both colonization and infection. Thus, it was hypothesized that transient targeting of IL-10 might represent an innovative way to improve vaccine efficacy. In this study, IL-10 expression was elevated in the nares of persistent carriers of S. aureus, and this was associated with reduced systemic S. aureus-specific Th1 responses. This suggests that systemic responses are remodeled because of commensal exposure to S. aureus, which negatively implicates vaccine function. To provide proof of concept that targeting immunosuppressive responses during immunization may be a useful approach to improve vaccine efficacy, we immunized mice with T cell-activating vaccines in combination with IL-10-neutralizing antibodies. Blocking IL-10 during vaccination enhanced effector T cell responses and improved bacterial clearance during subsequent systemic and subcutaneous infection. Taken together, these results reveal a potentially novel strategy for improving anti-S. aureus vaccine efficacy.


Asunto(s)
Interleucina-10 , Infecciones Estafilocócicas , Vacunas Estafilocócicas , Staphylococcus aureus , Interleucina-10/metabolismo , Interleucina-10/inmunología , Animales , Infecciones Estafilocócicas/prevención & control , Infecciones Estafilocócicas/inmunología , Vacunas Estafilocócicas/inmunología , Ratones , Staphylococcus aureus/inmunología , Femenino , Ratones Endogámicos C57BL , Células TH1/inmunología , Inmunización/métodos , Humanos , Anticuerpos Neutralizantes/inmunología , Eficacia de las Vacunas , Vacunación/métodos
17.
PLoS One ; 19(7): e0305211, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38968222

RESUMEN

Staphylococcus pseudintermedius is an opportunistic pathogen in dogs, and infection in humans is increasingly found, often linked to contact with dogs. We conducted a retrospective genotyping and antimicrobial susceptibility testing study of 406 S. pseudintermedius isolates cultured from animals (dogs, cats and an otter) and humans across Scotland, from 2007 to 2020. Seventy-five sequence types (STs) were identified, among the 130 isolates genotyped, with 59 seen only once. We observed the emergence of two methicillin resistant Staphylococcus pseudintermedius (MRSP) clones in Scotland: ST726, a novel locally-evolving clone, and ST551, first reported in 2015 in Poland, possibly linked to animal importation to Scotland from Central Europe. While ST71 was the most frequent S. pseudintermedius strain detected, other lineages that have been replacing ST71 in other countries, in addition to ST551, were detected. Multidrug resistance (MDR) was detected in 96.4% of MRSP and 8.4% of MSSP. A single MRSP isolate was resistant to mupirocin. Continuous surveillance for the emergence and dissemination of novel MDR MRSP in animals and humans and changes in antimicrobial susceptibility in S. pseudintermedius is warranted to minimise the threat to animal and human health.


Asunto(s)
Resistencia a la Meticilina , Mascotas , Infecciones Estafilocócicas , Staphylococcus , Secuenciación Completa del Genoma , Animales , Escocia , Staphylococcus/genética , Staphylococcus/efectos de los fármacos , Staphylococcus/aislamiento & purificación , Perros/microbiología , Gatos/microbiología , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/veterinaria , Infecciones Estafilocócicas/epidemiología , Humanos , Resistencia a la Meticilina/genética , Mascotas/microbiología , Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana , Estudios Retrospectivos , Enfermedades de los Perros/microbiología , Farmacorresistencia Bacteriana Múltiple/genética , Enfermedades de los Gatos/microbiología
18.
PLoS One ; 19(7): e0303395, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38968223

RESUMEN

BACKGROUND: Phenome-Wide Association study (PheWAS) is a powerful tool designed to systematically screen clinical observations derived from medical records (phenotypes) for association with a variable of interest. Despite their usefulness, no systematic screening of phenotypes associated with Staphylococcus aureus infections (SAIs) has been done leaving potential novel risk factors or complications undiscovered. METHOD AND COHORTS: We tailored the PheWAS approach into a two-stage screening procedure to identify novel phenotypes correlating with SAIs. The first stage screened for co-occurrence of SAIs with other phenotypes within medical records. In the second stage, significant findings were examined for the correlations between their age of onset with that of SAIs. The PheWAS was implemented using the medical records of 754,401 patients from the Marshfield Clinic Health System. Any novel associations discovered were subsequently validated using datasets from TriNetX and All of Us, encompassing 109,884,571 and 118,538 patients respectively. RESULTS: Forty-one phenotypes met the significance criteria of a p-value < 3.64e-5 and odds ratios of > 5. Out of these, we classified 23 associations either as risk factors or as complications of SAIs. Three novel associations were discovered and classified either as a risk (long-term use of aspirin) or complications (iron deficiency anemia and anemia of chronic disease). All novel associations were replicated in the TriNetX cohort. In the All of Us cohort, anemia of chronic disease was replicated according to our significance criteria. CONCLUSIONS: The PheWAS of SAIs expands our understanding of SAIs interacting phenotypes. Additionally, the novel two-stage PheWAS approach developed in this study can be applied to examine other disease-disease interactions of interest. Due to the possibility of bias inherent in observational data, the findings of this study require further investigation.


Asunto(s)
Fenotipo , Infecciones Estafilocócicas , Staphylococcus aureus , Humanos , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/genética , Staphylococcus aureus/genética , Masculino , Femenino , Persona de Mediana Edad , Adulto , Anciano , Fenómica , Estudio de Asociación del Genoma Completo , Adolescente , Factores de Riesgo , Adulto Joven , Niño
19.
PLoS One ; 19(7): e0305920, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38968271

RESUMEN

Sepsis is a life-threatening condition mainly caused by gram-negative and gram-positive bacteria. Understanding the type of causative agent in the early stages is essential for precise antibiotic therapy. This study sought to identify a host gene set capable of distinguishing between sepsis induced by gram-negative bacteria; Escherichia coli and gram-positive bacteria; Staphylococcus aureus in community-onset adult patients. In the present study, microarray expression information was used to apply the Least Absolute Shrinkage and Selection Operator (Lasso) technique to select the predictive gene set for classifying sepsis induced by E. coli or S. aureus pathogens. We identified 25 predictive genes, including LILRA5 and TNFAIP6, which had previously been associated with sepsis in other research. Using these genes, we trained a logistic regression classifier to distinguish whether a sample contains an E. coli or S. aureus infection or belongs to a healthy control group, and subsequently assessed its performance. The classifier achieved an Area Under the Curve (AUC) of 0.96 for E. coli and 0.98 for S. aureus-induced sepsis, and perfect discrimination (AUC of 1) for healthy controls from the other conditions in a 10-fold cross-validation. The genes demonstrated an AUC of 0.75 in distinguishing between sepsis patients with E. coli and S. aureus pathogens. These findings were further confirmed in two distinct independent validation datasets which gave high prediction AUC ranging from 0.72-0.87 and 0.62 in distinguishing three groups of participants and two groups of patients respectively. These genes were significantly enriched in the immune system, cytokine signaling in immune system, innate immune system, and interferon signaling. Transcriptional patterns in blood can differentiate patients with E. coli-induced sepsis from those with S. aureus-induced sepsis. These diagnostic markers, upon validation in larger trials, may serve as a foundation for a reliable differential diagnostics assay.


Asunto(s)
Infecciones por Escherichia coli , Escherichia coli , Sepsis , Infecciones Estafilocócicas , Staphylococcus aureus , Humanos , Sepsis/microbiología , Sepsis/genética , Sepsis/diagnóstico , Staphylococcus aureus/genética , Escherichia coli/genética , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/genética , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/genética , Adulto , Biomarcadores , Masculino , Femenino , Perfilación de la Expresión Génica , Persona de Mediana Edad
20.
BMC Microbiol ; 24(1): 241, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38961344

RESUMEN

BACKGROUND: Staphylococcus aureus, a commensal bacterium, colonizes the skin and mucous membranes of approximately 30% of the human population. Apart from conventional resistance mechanisms, one of the pathogenic features of S. aureus is its ability to survive in a biofilm state on both biotic and abiotic surfaces. Due to this characteristic, S. aureus is a major cause of human infections, with Methicillin-Resistant Staphylococcus aureus (MRSA) being a significant contributor to both community-acquired and hospital-acquired infections. RESULTS: Analyzing non-repetitive clinical isolates of MRSA collected from seven provinces and cities in China between 2014 and 2020, it was observed that 53.2% of the MRSA isolates exhibited varying degrees of ability to produce biofilm. The biofilm positivity rate was notably high in MRSA isolates from Guangdong, Jiangxi, and Hubei. The predominant MRSA strains collected in this study were of sequence types ST59, ST5, and ST239, with the biofilm-producing capability mainly distributed among moderate and weak biofilm producers within these ST types. Notably, certain sequence types, such as ST88, exhibited a high prevalence of strong biofilm-producing strains. The study found that SCCmec IV was the predominant type among biofilm-positive MRSA, followed by SCCmec II. Comparing strains with weak and strong biofilm production capabilities, the positive rates of the sdrD and sdrE were higher in strong biofilm producers. The genetic determinants ebp, icaA, icaB, icaC, icaD, icaR, and sdrE were associated with strong biofilm production in MRSA. Additionally, biofilm-negative MRSA isolates showed higher sensitivity rates to cefalotin (94.8%), daptomycin (94.5%), mupirocin (86.5%), teicoplanin (94.5%), fusidic acid (81.0%), and dalbavancin (94.5%) compared to biofilm-positive MRSA isolates. The biofilm positivity rate was consistently above 50% in all collected specimen types. CONCLUSIONS: MRSA strains with biofilm production capability warrant increased vigilance.


Asunto(s)
Biopelículas , Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Staphylococcus aureus Resistente a Meticilina/fisiología , China/epidemiología , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/microbiología , Antibacterianos/farmacología , Genes Bacterianos/genética , Humanos
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