Superantigens promote Staphylococcus aureus bloodstream infection by eliciting pathogenic interferon-gamma production DOI Creative Commons
Stephen W. Tuffs, Mariya I. Goncheva,

Stacey X. Xu

et al.

Proceedings of the National Academy of Sciences, Journal Year: 2022, Volume and Issue: 119(8)

Published: Feb. 14, 2022

Staphylococcus aureus is a foremost bacterial pathogen responsible for vast array of human diseases. Staphylococcal superantigens (SAgs) constitute family exotoxins from S. that bind directly to major histocompatibility complex (MHC) class II and T cell receptors drive extensive activation cytokine release. Although these toxins have been implicated in serious disease, including toxic shock syndrome, the specific pathological mechanisms remain unclear. Herein, we aimed elucidate how SAgs contribute pathogenesis during bloodstream infections utilized transgenic mice encoding MHC render susceptible SAg activity. We demonstrate bacteremia by massively increasing burden liver, this was mediated CD4+ cells produced interferon gamma (IFN-γ) high levels SAg-dependent manner. Bacterial burdens were reduced blocking IFN-γ, phenocopying SAg-deletion mutant strains, inhibiting proinflammatory response. Infection kinetics flow cytometry analyses suggested macrophage-driven mechanism, which confirmed through macrophage-depletion experiments. Experiments demonstrated excessive IFN-γ allowed replicate efficiently within macrophages. This indicates promote survival manipulating immune response inhibit effective clearing Altogether, work implicates as critical therapeutic targets preventing persistent or severe disease.

Language: Английский

Late-Onset Sepsis Among Very Preterm Infants DOI
Dustin D. Flannery, Erika M. Edwards, Sarah A. Coggins

et al.

PEDIATRICS, Journal Year: 2022, Volume and Issue: 150(6)

Published: Nov. 11, 2022

OBJECTIVES To determine the epidemiology, microbiology, and associated outcomes of late-onset sepsis among very preterm infants using a large nationally representative cohort NICUs across United States. METHODS Prospective observational study born 401 to 1500 g and/or 22 29 weeks’ gestational age (GA) from January 1, 2018, December 31, 2020, who survived >3 days in 774 participating Vermont Oxford Network centers. Late-onset was defined as isolation pathogenic bacteria blood cerebrospinal fluid, or fungi blood, obtained after birth. Demographics, clinical characteristics, were compared between with without sepsis. RESULTS Of 118 650 infants, 10 501 (8.9%) had for an incidence rate 88.5 per 1000 (99% confidence interval [CI] [86.4–90.7]). Incidence highest ≤23 weeks GA (322.0 1000, 99% CI [306.3–338.1]). The most common pathogens coagulase negative staphylococci (29.3%) Staphylococcus aureus (23.0%), but 34 different identified. Infected lower survival (adjusted risk ratio [aRR] 0.89, 95% [0.87–0.90]) increased risks home oxygen (aRR 1.32, [1.26–1.38]), tracheostomy 2.88, [2.47–3.37]), gastrostomy 2.09, [1.93–2.57]) survivors. CONCLUSIONS A substantial proportion continue suffer sepsis, particularly those at lowest GAs. higher mortality, survivors technology-dependent chronic morbidities. persistent burden diverse microbiology underscore need innovative potentially organism-specific prevention strategies.

Language: Английский

Citations

81

Biofilm Producing Methicillin-Resistant Staphylococcus aureus (MRSA) Infections in Humans: Clinical Implications and Management DOI Creative Commons
Ashlesha Kaushik, Helen Kest, Mangla Sood

et al.

Pathogens, Journal Year: 2024, Volume and Issue: 13(1), P. 76 - 76

Published: Jan. 15, 2024

Since its initial description in the 1960s, methicillin-resistant Staphylococcus aureus (MRSA) has developed multiple mechanisms for antimicrobial resistance and evading immune system, including biofilm production. MRSA is now a widespread pathogen, causing spectrum of infections ranging from superficial skin issues to severe conditions like osteoarticular endocarditis, leading high morbidity mortality. Biofilm production key aspect MRSA’s ability invade, spread, resist treatments. Environmental factors, such as suboptimal antibiotics, pH, temperature, tissue oxygen levels, enhance formation. Biofilms are intricate bacterial structures with dense organisms embedded polysaccharides, promoting their resilience. The process involves stages attachment, expansion, maturation, eventually disassembly or dispersion. formation complex molecular foundation, involving genes icaADBC, fnbA, fnbB, clfA, clfB, atl, agr, sarA, sarZ, sigB, sarX, psm, icaR, srtA. Recognizing pivotal led potential therapeutic strategies targeting elemental enzymatic properties combat biofilms. This review provides practical approach healthcare practitioners, addressing pathogenesis, disease spectrum, management guidelines, advances treatment. Effective appropriate therapy, surgical interventions, foreign body removal, robust infection control practices curtail spread within environments.

Language: Английский

Citations

41

The role of Staphylococcus aureus quorum sensing in cutaneous and systemic infections DOI Creative Commons
Yuriko Yamazaki, Tomoka Ito, Masakazu Tamai

et al.

Inflammation and Regeneration, Journal Year: 2024, Volume and Issue: 44(1)

Published: March 1, 2024

Abstract Background Staphylococcus aureus is a leading cause of human bacterial infections worldwide. It the most common causative agent skin and soft tissue infections, can also various other including pneumonia, osteomyelitis, as well life-threatening such sepsis infective endocarditis. The pathogen asymptomatically colonize skin, nasal cavity, intestine. S. colonizes approximately 20–30% nostrils, being an opportunistic for subsequent infection. Its strong ability to silently spread via contact makes it difficult eradicate S . A major concern with its capacity develop antibiotic resistance adapt diverse environmental conditions. variability in accessory gene regulator (Agr) region genome contributes spectrum phenotypes within population, enhancing likelihood survival different environments. Agr functions central quorum sensing (QS) system , allowing bacteria adjust expression response population density. Depending on expression, secretes toxins, contributing virulence infectious diseases. Paradoxically, expressing may be disadvantageous certain situations, hospitals, causing generate mutants responsible healthcare settings. Main body This review aims demonstrate molecular mechanisms governing ranging from harmless colonizer organism capable infecting organs. Emphasis will placed QS role orchestrating behavior across contexts. Short conclusion pathophysiology infection substantially influenced by phenotypic changes resulting factors beyond Agr. Future studies are expected give comprehensive understanding overall profile

Language: Английский

Citations

25

Staphylococcus aureus Infections and Human Intestinal Microbiota DOI Creative Commons

Aotong Liu,

Shari Garrett,

Wanqing Hong

et al.

Pathogens, Journal Year: 2024, Volume and Issue: 13(4), P. 276 - 276

Published: March 24, 2024

Staphylococcus aureus (S. aureus) is a common pathogen that can cause many human diseases, such as skin infection, food poisoning, endocarditis, and sepsis. These diseases be minor infections or life-threatening, requiring complex medical management resulting in substantial healthcare costs. Meanwhile, the critically ignored “organ,” intestinal microbiome greatly impacts physiological health, not only gastrointestinal but also disorders beyond gut. However, correlation between S. infection microbial homeostasis largely unknown. Here, we summarized recent progress understanding their interactions with intestine. summarizations will help us understand mechanisms behind these crosstalk challenges are facing now, which could contribute to preventing infections, effective treatment investigation, vaccine development.

Language: Английский

Citations

21

Towards a green climate: Production of slag–red brick waste-based geopolymer mingled with WO3 nanoparticles with bio-mechanical achievements DOI
Mostafa A. Sayed,

S.M.A. El-Gamal,

Alaa Mohsen

et al.

Construction and Building Materials, Journal Year: 2024, Volume and Issue: 413, P. 134909 - 134909

Published: Jan. 1, 2024

Language: Английский

Citations

17

Impeding Biofilm-Forming Mediated Methicillin-Resistant Staphylococcus aureus and Virulence Genes Using a Biosynthesized Silver Nanoparticles–Antibiotic Combination DOI Creative Commons
Mohamed A. Fareid, Gamal M. El-Sherbiny, Ahmed Askar

et al.

Biomolecules, Journal Year: 2025, Volume and Issue: 15(2), P. 266 - 266

Published: Feb. 11, 2025

Methicillin-resistant Staphylococcus aureus (MRSA) continues to represent a significant clinical challenge, characterized by consistently elevated rates of morbidity and mortality. Care regimen success is still difficult necessitates assessing new antibiotics as well supplemental services, including source control searching for alternative approaches combating it. Hence, we propose synthesize silver nanoparticles (Ag-NPs) employing cell-free filter (CFF) Streptomyces sp. augment antibiotic activity combat biofilm-forming MRSA. Seven bacterial isolates from samples were identified, profiled with Vitek-2, the phenotypic detecting biofilm Congo red medium microplate assay was carried out. The PCR technique used genes (icaA icaD) coded in forming. characterization Ag-NPs performed using several analytical methods, such UV spectroscopy, dynamic light scattering (DLS), zeta potential measurement, transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR). antibacterial properties oxacillin-Ag-NPs assessed against standard strains agar diffusion microdilution assay. biogenic synthesis resulted uniformly spherical particles, an average size 20 nm. These demonstrated MRSA, minimum inhibitory concentrations (MICs) ranging 12 15 μg/mL. Additionally, completely impede formation MRSA at sublethal doses 0.75 MICs. expression levels icaA icaD reduced 1.9- 2.2- 2.4- 2.8-fold, respectively. A synergistic effect noted when combination oxacillin, leading MICs 1.87 μg/mL oxacillin 4.0 FICi 0.375 further validated relationship between 4 Findings time-kill test highest reduction log10 (CFU)/mL initial inoculum after 12-hour exposure. cytotoxicity analysis revealed no cytotoxic effects on human skin cell line HFB-4 low concentrations, IC50 values 61.40 µg/mL 34.2 HepG-2. Comparable oxacillin-Ag-NPs, showed different exhibited value 31.2 HepG-2-cells. In conclusion, biosynthesis has effective hindered formation, suggesting valuable applications.

Language: Английский

Citations

2

Clinical outcomes of COVID-19 in Wuhan, China: a large cohort study DOI Creative Commons
Jiao Liu, Sheng Zhang, Zhixiong Wu

et al.

Annals of Intensive Care, Journal Year: 2020, Volume and Issue: 10(1)

Published: July 31, 2020

Since December 2019, an outbreak of Coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) initially emerged in Wuhan, China, and has spread worldwide now. Clinical features patients with COVID-19 have been described. However, risk factors leading to in-hospital deterioration poor prognosis not well identified. In this retrospective, single-center cohort study, 1190 adult inpatients (≥ 18 years old) laboratory-confirmed determined outcomes (discharged or died) were included from Wuhan Infectious Disease Hospital 29, February 28, 2020. The final follow-up date was March 2, data including characteristics, laboratory imaging information as treatments extracted electronic medical records compared. A multivariable logistic regression model used explore potential predictors associated death. confirmed included. Their median age 57 (interquartile range 47–67 years). Two hundred sixty-one (22%) developed a illness after admission. Multivariable demonstrated that higher SOFA score (OR 1.32, 95% CI 1.22–1.43, per increase, p < 0.001 for OR 1.30, 1.11–1.53, = death), lymphocytopenia 1.81, 1.13–2.89 0.013 deterioration; 4.44, 1.26–15.87, 0.021 death) on admission independent death patients. On D-dimer greater than 1 μg/L 3.28, 1.19–9.04, 0.021), leukocytopenia 5.10, 1.25–20.78), thrombocytopenia 8.37, 2.04–34.44) history diabetes 11.16, 1.87–66.57, 0.008) also risks Shorter time interval onset non-invasive mechanical ventilation survivors observed compared non-survivors (10.5 days, IQR 9.25–11.0 vs. 16.0 11.0–19.0 0.030). Treatment glucocorticoids increased progression 3.79, 2.39–6.01, 0.001). Administration antiviral drugs especially oseltamivir ganciclovir is decreased 0.17, 0.05–0.64, High could predict would develop in-hospital. elevated D-dimer, leukocytopenia, COVID-19. might be beneficial reducing mortality

Language: Английский

Citations

127

Preparation and optimization of ciprofloxacin encapsulated niosomes: A new approach for enhanced antibacterial activity, biofilm inhibition and reduced antibiotic resistance in ciprofloxacin-resistant methicillin-resistance Staphylococcus aureus DOI
Amir Mirzaie,

Niloufar Peirovi,

Iman Akbarzadeh

et al.

Bioorganic Chemistry, Journal Year: 2020, Volume and Issue: 103, P. 104231 - 104231

Published: Aug. 26, 2020

Language: Английский

Citations

98

The biogeography of infection revisited DOI
Sheyda Azimi, Gina R. Lewin, Marvin Whiteley

et al.

Nature Reviews Microbiology, Journal Year: 2022, Volume and Issue: 20(10), P. 579 - 592

Published: Feb. 8, 2022

Language: Английский

Citations

49

Low Dose of Sucralose Alter Gut Microbiome in Mice DOI Creative Commons
Zibin Zheng, Yingping Xiao,

Lingyan Ma

et al.

Frontiers in Nutrition, Journal Year: 2022, Volume and Issue: 9

Published: Feb. 25, 2022

Sucralose is a non-nutritive artificial sweetener (NNS) used in foods or beverages to control blood glucose levels and body weight gain. The consumption of NNS has increased recent years over the world, many researches have indicated long-term sucralose administration altered gut microbiome composition mice. These studies all focus on US Food Drug Administration (FDA) defined acceptable daily intake (ADI), approximately 5 mg/kg BW/day for human. In our study, mice were given with T1-4 (0.0003, 0.003, 0.03, 0.3 mg/mL) sucralose, respectively, Control group normal water. particular, mg/mL was equal ADI (5 BW/day). After 16 weeks, weighted sacrificed, liver each mouse isolated weighed, segments jejunum, ileum colon collected H&E-stained. contents ileum, cecum 16S rRNA gene sequencing. results showed affects intestinal barrier function evidenced by distinct lymphocyte aggregation while not change weight. sequencing suggested significantly changed microbiota, especially T1 T4 group. For example, reduction probiotics abundance (Lachnoclostridium Lachnospiraceae) found compared On other hand, Allobaculum, which reported positively correlated diabetes, addition, potential pathogens, including Tenacibaculum, Ruegeria, Staphylococcus also new findings indicate that low dose (T1) alter mice, these adverse health effects are level (T4). Overall, study provides guidance suggestions use beverages.

Language: Английский

Citations

39