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2.
BMC Microbiol ; 24(1): 246, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38970013

ABSTRACT

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.


Subject(s)
Candida albicans , Methicillin-Resistant Staphylococcus aureus , Photosensitizing Agents , Potassium Iodide , Rose Bengal , Staphylococcal Infections , Wound Healing , Animals , Rose Bengal/pharmacology , Methicillin-Resistant Staphylococcus aureus/drug effects , Wound Healing/drug effects , Potassium Iodide/pharmacology , Mice , Candida albicans/drug effects , Photosensitizing Agents/pharmacology , Staphylococcal Infections/drug therapy , Staphylococcal Infections/microbiology , Escherichia coli/drug effects , Diabetes Mellitus, Experimental/microbiology , Diabetes Mellitus, Experimental/drug therapy , Photochemotherapy/methods , Drug Synergism , Light , Male
4.
Methods Mol Biol ; 2833: 1-10, 2024.
Article in English | MEDLINE | ID: mdl-38949695

ABSTRACT

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.


Subject(s)
Anti-Bacterial Agents , Disease Models, Animal , Larva , Staphylococcal Infections , Staphylococcus aureus , Zebrafish , Animals , Zebrafish/microbiology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Staphylococcus aureus/drug effects , Larva/microbiology , Larva/drug effects , Staphylococcal Infections/drug therapy , Staphylococcal Infections/microbiology , Drug Therapy, Combination , Host-Pathogen Interactions/drug effects , Microbial Sensitivity Tests
5.
Sci Transl Med ; 16(754): eadi6887, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38959328

ABSTRACT

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.


Subject(s)
COVID-19 , Class Ib Phosphatidylinositol 3-Kinase , Inflammation , SARS-CoV-2 , COVID-19/pathology , Class Ib Phosphatidylinositol 3-Kinase/metabolism , Animals , Inflammation/pathology , Humans , COVID-19 Drug Treatment , Methicillin-Resistant Staphylococcus aureus/drug effects , Mice , Lung/pathology , Phosphoinositide-3 Kinase Inhibitors/pharmacology , Phosphoinositide-3 Kinase Inhibitors/therapeutic use , Cytokine Release Syndrome/drug therapy , Capillary Permeability/drug effects , Mice, Inbred C57BL , Staphylococcal Infections/drug therapy , Staphylococcal Infections/pathology
6.
Sci Rep ; 14(1): 15737, 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38977804

ABSTRACT

The COVID-19 pandemic has significantly transformed the infection spectrum of various pathogens. This study aimed to evaluate the impact of the COVID-19 pandemic on Staphylococcus aureus (S. aureus) infections among pediatric patients with community acquired pneumonia (CAP). We retrospectively reviewed pediatric CAP admissions before (from 2018 to 2019) and during (from 2020 to 2022) the COVID-19 pandemic. The epidemiology and antimicrobial resistance (AMR) profiles of S. aureus isolates were examined to assess the pandemic's effect. As a result, a total of 399 pediatric CAP patients with S. aureus infections were included. The positivity rate, gender, and age distribution of patients were similar across both periods. There was a marked reduction in respiratory co-infections with Haemophilus influenzae (H. influenzae) during the COVID-19 pandemic, compared to 2019. Additionally, there were significant changes in the resistance profiles of S. aureus isolates to various antibiotics. Resistance to oxacillin and tetracycline increased, whereas resistance to penicillin, gentamicin, and quinolones decreased. Notably, resistance to erythromycin significantly decreased in methicillin-resistant S. aureus (MRSA) strains. The number of S. aureus isolates, the proportion of viral co-infections, and the number of resistant strains typically peaked seasonally, primarily in the first or fourth quarters of 2018, 2019, and 2021. However, shifts in these patterns were noted in the first quarter of 2020 and the fourth quarter of 2022. These findings reveal that the COVID-19 pandemic has significantly altered the infection dynamics of S. aureus among pediatric CAP patients, as evidenced by changes in respiratory co-infections, AMR patterns, and seasonal trends.


Subject(s)
Anti-Bacterial Agents , COVID-19 , Community-Acquired Infections , Staphylococcal Infections , Staphylococcus aureus , Humans , COVID-19/epidemiology , COVID-19/microbiology , COVID-19/complications , Community-Acquired Infections/epidemiology , Community-Acquired Infections/microbiology , Community-Acquired Infections/drug therapy , Female , Male , Child , Child, Preschool , Retrospective Studies , Staphylococcus aureus/drug effects , Staphylococcus aureus/isolation & purification , Infant , Staphylococcal Infections/epidemiology , Staphylococcal Infections/drug therapy , Staphylococcal Infections/microbiology , Anti-Bacterial Agents/therapeutic use , Anti-Bacterial Agents/pharmacology , Adolescent , Coinfection/epidemiology , Coinfection/microbiology , SARS-CoV-2/isolation & purification , SARS-CoV-2/drug effects , Methicillin-Resistant Staphylococcus aureus/drug effects , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Pandemics , Hospitalization , Drug Resistance, Bacterial
7.
BMC Biotechnol ; 24(1): 47, 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38978013

ABSTRACT

The threat of methicillin-resistant Staphylococcus aureus (MRSA) is increasing worldwide, making it significantly necessary to discover a novel way of dealing with related infections. The quick spread of MRSA isolates among infected individuals has heightened public health concerns and significantly limited treatment options. Vancomycin (VAN) can be applied to treat severe MRSA infections, and the indiscriminate administration of this antimicrobial agent has caused several concerns in medical settings. Owing to several advantageous characteristics, a niosomal drug delivery system may increase the potential of loaded antimicrobial agents. This work aims to examine the antibacterial and anti-biofilm properties of VAN-niosome against MRSA clinical isolates with emphasis on cytotoxicity and stability studies. Furthermore, we aim to suggest an effective approach against MRSA infections by investigating the inhibitory effect of formulated niosome on the expression of the biofilm-associated gene (icaR). The thin-film hydration approach was used to prepare the niosome (Tween 60, Span 60, and cholesterol), and field emission scanning electron microscopy (FE-SEM), an in vitro drug release, dynamic light scattering (DLS), and entrapment efficiency (EE%) were used to investigate the physicochemical properties. The physical stability of VAN-niosome, including hydrodynamic size, polydispersity index (PDI), and EE%, was analyzed for a 30-day storage time at 4 °C and 25 °C. In addition, the human foreskin fibroblast (HFF) cell line was used to evaluate the cytotoxic effect of synthesized niosome. Moreover, minimum inhibitory and bactericidal concentrations (MICs/MBCs) were applied to assess the antibacterial properties of niosomal VAN formulation. Also, the antibiofilm potential of VAN-niosome was investigated by microtiter plate (MTP) and real-time PCR methods. The FE-SEM result revealed that synthesized VAN-niosome had a spherical morphology. The hydrodynamic size and PDI of VAN-niosome reported by the DLS method were 201.2 nm and 0.301, respectively. Also, the surface zeta charge of the prepared niosome was - 35.4 mV, and the EE% ranged between 58.9 and 62.5%. Moreover, in vitro release study revealed a sustained-release profile for synthesized niosomal formulation. Our study showed that VAN-niosome had acceptable stability during a 30-day storage time. Additionally, the VAN-niosome had stronger antibacterial and anti-biofilm properties against MRSA clinical isolates compared with free VAN. In conclusion, the result of our study demonstrated that niosomal VAN could be promising as a successful drug delivery system due to sustained drug release, negligible toxicity, and high encapsulation capacity. Also, the antibacterial and anti-biofilm studies showed the high capacity of VAN-niosome against MRSA clinical isolates. Furthermore, the results of real-time PCR exhibited that VAN-niosome could be proposed as a powerful strategy against MRSA biofilm via down-regulation of icaR gene expression.


Subject(s)
Anti-Bacterial Agents , Biofilms , Drug Delivery Systems , Liposomes , Methicillin-Resistant Staphylococcus aureus , Vancomycin , Biofilms/drug effects , Methicillin-Resistant Staphylococcus aureus/drug effects , Methicillin-Resistant Staphylococcus aureus/physiology , Vancomycin/pharmacology , Vancomycin/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Liposomes/chemistry , Humans , Microbial Sensitivity Tests , Staphylococcal Infections/drug therapy , Staphylococcal Infections/microbiology , Drug Liberation
8.
FASEB J ; 38(14): e23801, 2024 Jul 31.
Article in English | MEDLINE | ID: mdl-39018106

ABSTRACT

Intracellular pathogens including Staphylococcus aureus contribute to the non-healing phenotype of chronic wounds. Lactobacilli, well known as beneficial bacteria, are also reported to modulate the immune system, yet their role in cutaneous immunity remains largely unknown. We explored the therapeutic potential of bacteria-free postbiotics, bioactive lysates of lactobacilli, to reduce intracellular S. aureus colonization and promote healing. Fourteen postbiotics derived from various lactobacilli species were screened, and Latilactobacillus curvatus BGMK2-41 was selected for further analysis based on the most efficient ability to reduce intracellular infection by S. aureus diabetic foot ulcer clinical isolate and S. aureus USA300. Treatment of both infected keratinocytes in vitro and infected human skin ex vivo with BGMK2-41 postbiotic cleared S. aureus. Keratinocytes treated in vitro with BGMK2-41 upregulated expression of antimicrobial response genes, of which DEFB4, ANG, and RNASE7 were also found upregulated in treated ex vivo human skin together with CAMP exclusively upregulated ex vivo. Furthermore, BGMK2-41 postbiotic treatment has a multifaceted impact on the wound healing process. Treatment of keratinocytes stimulated cell migration and the expression of tight junction proteins, while in ex vivo human skin BGMK2-41 increased expression of anti-inflammatory cytokine IL-10, promoted re-epithelialization, and restored the epidermal barrier via upregulation of tight junction proteins. Together, this provides a potential therapeutic approach for persistent intracellular S. aureus infections.


Subject(s)
Keratinocytes , Lactobacillus , Staphylococcus aureus , Humans , Keratinocytes/microbiology , Keratinocytes/metabolism , Keratinocytes/drug effects , Skin/microbiology , Skin/metabolism , Wound Healing/drug effects , Probiotics/pharmacology , Staphylococcal Infections/microbiology , Staphylococcal Infections/drug therapy , Staphylococcal Infections/metabolism , Ribonucleases/metabolism
9.
Int J Mol Sci ; 25(13)2024 Jul 07.
Article in English | MEDLINE | ID: mdl-39000566

ABSTRACT

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.


Subject(s)
CD4-Positive T-Lymphocytes , Lymphocyte Activation , Piperidines , Pyrimidines , Shock, Septic , Staphylococcal Infections , Th1 Cells , Animals , Piperidines/pharmacology , Piperidines/therapeutic use , Th1 Cells/immunology , Th1 Cells/drug effects , Th1 Cells/metabolism , Pyrimidines/pharmacology , Pyrimidines/therapeutic use , Shock, Septic/drug therapy , Shock, Septic/immunology , Shock, Septic/chemically induced , Mice , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/drug effects , CD4-Positive T-Lymphocytes/metabolism , Lymphocyte Activation/drug effects , Staphylococcal Infections/drug therapy , Staphylococcal Infections/immunology , Staphylococcal Infections/microbiology , Enterotoxins , Staphylococcus aureus/drug effects , Cytokines/metabolism , CD8-Positive T-Lymphocytes/drug effects , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/metabolism , Mice, Inbred C57BL , Female , Disease Models, Animal , Superantigens/immunology
10.
World J Microbiol Biotechnol ; 40(9): 265, 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38990361

ABSTRACT

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.


Subject(s)
Anti-Bacterial Agents , Bacterial Proteins , Hemolysin Proteins , Methicillin-Resistant Staphylococcus aureus , Virulence Factors , Animals , Female , Humans , Mice , A549 Cells , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/metabolism , Bacterial Proteins/genetics , Bacterial Toxins/metabolism , Disease Models, Animal , Hemolysin Proteins/metabolism , Hemolysis/drug effects , Methicillin-Resistant Staphylococcus aureus/drug effects , Mice, Inbred BALB C , Quorum Sensing/drug effects , Staphylococcal Infections/drug therapy , Staphylococcal Infections/microbiology , Virulence/drug effects , Virulence Factors/metabolism
11.
New Microbiol ; 47(2): 183-185, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39023529

ABSTRACT

Staphylococcus aureus bacteremia presents clinical complexities, with prolonged duration associated with unfavorable outcomes. This research delves into unconventional treatments, such as combinations involving daptomycin, oxacillin, ceftaroline, and fosfomycin, with the aim of swiftly sterilizing bloodstream infection to reduce complications. Our examination of 30 MSSA bacteremia patients with infective endocarditis uncovers differing results between single-agent therapies (oxacillin or daptomycin) and combined treatment plans. Microbiologic clearance at the 72 hour mark demonstrates greater efficacy within the combination cohort (bacteremia persistence 29%) versus monotherapy (bacteremia persistence 78%). This limited case series suggests the potential superiority of combination therapy, prompting further investigations.


Subject(s)
Anti-Bacterial Agents , Bacteremia , Drug Therapy, Combination , Staphylococcal Infections , Staphylococcus aureus , Humans , Bacteremia/drug therapy , Bacteremia/microbiology , Anti-Bacterial Agents/therapeutic use , Anti-Bacterial Agents/administration & dosage , Staphylococcal Infections/drug therapy , Staphylococcal Infections/microbiology , Staphylococcus aureus/drug effects , Male , Female , Middle Aged , Aged , Adult , Daptomycin/therapeutic use , Daptomycin/administration & dosage
12.
ACS Nano ; 18(26): 17086-17099, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38952327

ABSTRACT

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.


Subject(s)
Microwaves , Photochemotherapy , Animals , Mice , Reactive Oxygen Species/metabolism , Wireless Technology , Photosensitizing Agents/pharmacology , Photosensitizing Agents/chemistry , Light , Staphylococcus aureus/drug effects , Staphylococcal Infections/drug therapy , Mice, Inbred BALB C , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry
14.
Int J Nanomedicine ; 19: 6319-6336, 2024.
Article in English | MEDLINE | ID: mdl-38919773

ABSTRACT

Purpose: This research was to innovate a nanozyme-based therapeutic strategy that combines aggregation-induced emission (AIE) photosensitizers with copper nanozymes. This approach is designed to address the hypoxic conditions often found in bacterial infections and aims to boost the effectiveness of photodynamic therapy (PDT) by ensuring sufficient oxygen supply for reactive oxygen species (ROS) generation. Methods: Our approach involved the synthesis of dihydroxyl triphenyl vinyl pyridine (DHTPY)-Cu@zoledronic acid (ZOL) nanozyme particles. We initially synthesized DHTPY and then combined it with copper nanozymes to form the DHTPY-Cu@ZOL composite. The nanozyme's size, morphology, and chemical properties were characterized using various techniques, including dynamic light scattering, transmission electron microscopy, and X-ray photoelectron spectroscopy. We conducted a series of in vitro and in vivo tests to evaluate the photodynamic, antibacterial, and wound-healing properties of the DHTPY-Cu@ZOL nanozymes, including their oxygen-generation capacity, ROS production, and antibacterial efficacy against methicillin-resistant Staphylococcus aureus (MRSA). Results: The DHTPY-Cu@ZOL exhibited proficient H2O2 scavenging and oxygen generation, crucial for enhancing PDT in oxygen-deprived infection environments. Our in vitro analysis revealed a notable antibacterial effect against MRSA, suggesting the nanozymes' potential to disrupt bacterial cell membranes. Further, in vivo studies using a diabetic rat model with MRSA-infected wounds showed that DHTPY-Cu@ZOL markedly improved wound healing and reduced bacterial presence, underscoring its efficacy as a non-antibiotic approach for chronic infections. Conclusion: Our study suggests that DHTPY-Cu@ZOL is a highly promising approach for combating antibiotic-resistant microbial pathogens and biofilms. The biocompatibility and stability of these nanozyme particles, coupled with their improved PDT efficacy position them as a promising candidate for clinical applications.


Subject(s)
Anti-Bacterial Agents , Copper , Methicillin-Resistant Staphylococcus aureus , Photochemotherapy , Photosensitizing Agents , Wound Infection , Photochemotherapy/methods , Animals , Methicillin-Resistant Staphylococcus aureus/drug effects , Copper/chemistry , Copper/pharmacology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Photosensitizing Agents/chemistry , Photosensitizing Agents/pharmacology , Wound Infection/drug therapy , Wound Infection/microbiology , Staphylococcal Infections/drug therapy , Reactive Oxygen Species/metabolism , Imidazoles/chemistry , Imidazoles/pharmacology , Pyridines/chemistry , Pyridines/pharmacology , Rats , Wound Healing/drug effects , Male , Humans , Rats, Sprague-Dawley
15.
J Mater Chem B ; 12(25): 6164-6174, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38828762

ABSTRACT

Catalytic therapy based on nanozymes is promising for the treatment of bacterial infections. However, its therapeutic efficacy is usually restricted by the limited amount of hydrogen peroxide and the weak acidic environment in infected tissues. To solve these issues, we prepared polyvinyl alcohol (PVA)-polyacrylic acid (PAA)-iron oxide (Fe3O4)/polyvinyl alcohol (PVA)-zinc peroxide (ZnO2) double-layer electrospun nanofibers (PPF/PZ NFs). In this design, PVA serves as the carrier for ZnO2 nanoparticles (NPs), Fe3O4 NPs, and PAA. The double-layer structure of nanofibers can spatially separate the PAA and ZnO2 to avoid their reaction with each other during preparation and storage, while in the wet wound bed, PVA can dissolve and PAA can provide H+ ions to promote the generation of hydrogen peroxide and subsequent conversion to hydroxyl radicals for bacteria killing. In vitro experimental results demonstrated that PPF/PZ NFs can reduce the methicillin-resistant Staphylococcus aureus by 3.1 log (99.92%). Moreover, PPF/PZ NFs can efficiently treat the bacterial infection in a mouse wound model and promote wound healing with negligible toxicity to animals, indicating their potential use as "plug-and-play" antibacterial wound dressings. This work provides a novel strategy for the construction of double-layer electrospun nanofibers as catalytic wound dressings with hydrogen peroxide/acid self-supplying properties for the efficient treatment of bacterial infections.


Subject(s)
Anti-Bacterial Agents , Hydrogen Peroxide , Methicillin-Resistant Staphylococcus aureus , Nanofibers , Wound Infection , Zinc Oxide , Nanofibers/chemistry , Animals , Mice , Hydrogen Peroxide/chemistry , Hydrogen Peroxide/pharmacology , Catalysis , Methicillin-Resistant Staphylococcus aureus/drug effects , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Wound Infection/drug therapy , Zinc Oxide/chemistry , Zinc Oxide/pharmacology , Polyvinyl Alcohol/chemistry , Acrylic Resins/chemistry , Acrylic Resins/pharmacology , Wound Healing/drug effects , Microbial Sensitivity Tests , Staphylococcal Infections/drug therapy , Particle Size
16.
BMC Infect Dis ; 24(1): 634, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38918705

ABSTRACT

BACKGROUND: CKD patients on hemodialysis (HD) with Staphylococcus aureus (SA) bacteremia present high morbidity, mortality and increased risk of MRSA. Vancomycin is the antibiotic of choice in these cases, it has a narrow therapeutic margin and inadequate dosage generates a risk of toxicity, therefore, the recommendation is to dosage it through serum levels. METHODS: This is a retrospective cohort study in 3 hospitals of third level of complexity in the city of Medellin in which there were differences in the measurement and implementation of vancomycin25 dosage based on trough levels (VL) in patients with chronic kidney disease on hemodialysis (CKD- HD) with uncomplicated bacteremia based infection by methilcillin-resistant Staphyloccocus aureus (MRSA). The primary outcome was the composite of hospital mortality, clinical response (fever, hemodynamic instability and altered consciousness), complications associated with bacteremia, or bacteriological response failure (positive cultures at first week follow-up) at 7 days. The composite variables were analyzed individually as secondary outcomes. RESULTS: The main unadjusted outcome (OR 1.3, CI 0.6 - 2.7) and adjusted for age, Charlson index, loading dose, initial dose, dosing frequency and MIC to vancomycin (OR 1.2, CI 0.5 - 2.7). Regarding adjusted secondary outcomes: clinical response (OR 1.4 CI 0.3 - 5.8), death (OR 1.3 CI 0.3 - 4.6) and complications (OR 0.9, CI 0.37 - 2.2). CONCLUSIONS: We conclude that the measurement of trough levels in patients with HD-CKD does not modify the composite outcome. The main limitation is the sample size and type of study, randomized control trials may be required to confirm the results presented.


Subject(s)
Anti-Bacterial Agents , Bacteremia , Methicillin-Resistant Staphylococcus aureus , Renal Dialysis , Renal Insufficiency, Chronic , Staphylococcal Infections , Vancomycin , Humans , Vancomycin/therapeutic use , Retrospective Studies , Bacteremia/drug therapy , Bacteremia/microbiology , Staphylococcal Infections/drug therapy , Staphylococcal Infections/microbiology , Male , Renal Dialysis/adverse effects , Female , Renal Insufficiency, Chronic/complications , Aged , Methicillin-Resistant Staphylococcus aureus/drug effects , Middle Aged , Anti-Bacterial Agents/therapeutic use , Anti-Bacterial Agents/pharmacokinetics , Anti-Bacterial Agents/administration & dosage , Aged, 80 and over , Microbial Sensitivity Tests
17.
Nanoscale ; 16(24): 11669-11678, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38855849

ABSTRACT

Implant infections are severe complications in clinical treatment, which often accompany the formation of bacterial biofilms with high antibiotic resistance. Sonodynamic therapy (SDT) is an antibiotic-free method that can generate reactive oxygen species (ROS) to kill bacteria under ultrasound (US) treatment. However, the extracellular polymeric substances (EPS) barrier of bacterial biofilms and the hypoxic microenvironment significantly limit the antibiofilm activity of SDT. In this study, lipid-shelled perfluoropentane (PFP) nanodroplets loaded with gallium protoporphyrin IX (GaPPIX) and oxygen (O2) (LPGO NDs) were developed for the treatment of implant infections. Under US stimulation, LPGO NDs undergo the cavitation effect and disrupt the biofilm structure like bombs due to liquid-gas phase transition. Meanwhile, the LPGO NDs release O2 and GaPPIX upon US stimulation. The released O2 can alleviate the hypoxic microenvironment in the biofilm and enhance the ROS formation by GaPPIX for enhanced bacterial killing. In vivo experimental results demonstrate that the LPGO NDs can efficiently treat implant infections of methicillin-resistant Staphylococcus aureus (MRSA) in a mouse model by disrupting the biofilm structure, alleviating hypoxia, and enhancing bacterial killing by SDT. Therefore, this work provides a new multifunctional sonosensitizer to overcome the limitations of SDT for treating implant infections.


Subject(s)
Biofilms , Fluorocarbons , Gallium , Methicillin-Resistant Staphylococcus aureus , Oxygen , Protoporphyrins , Staphylococcal Infections , Ultrasonic Therapy , Animals , Fluorocarbons/chemistry , Fluorocarbons/pharmacology , Mice , Gallium/chemistry , Gallium/pharmacology , Protoporphyrins/chemistry , Protoporphyrins/pharmacology , Methicillin-Resistant Staphylococcus aureus/drug effects , Biofilms/drug effects , Oxygen/chemistry , Staphylococcal Infections/drug therapy , Reactive Oxygen Species/metabolism , Nanoparticles/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Mice, Inbred BALB C , Female , Pentanes
18.
Biomed Res Int ; 2024: 6758817, 2024.
Article in English | MEDLINE | ID: mdl-38899039

ABSTRACT

Materials and Methods: In a research experiment, 48 male Wistar rats were anesthetized and second-degree burns were induced on their backs. The rats' wounds were then uniformly inoculated with MRSA. Various treatments were applied to the burn wounds daily, including Myrtus ointment, silver nanoparticles, silver nanoparticles-Myrtus ointment, silver sulfadiazine-Myrtus ointment, silver sulfadiazine 1%, mupirocin ointment, and a positive control. The study measured the antimicrobial effects, wound area, percentage of wound healing, antioxidant capacities, malondialdehyde, and nitric oxide concentrations in the serum of the rats. Data analysis was performed using GraphPad software, with one-way ANOVA and Tukey's tests used to determine the statistical significance of the results. Results: Rats treated with Myrtus ointment, silver nanoparticles-Myrtus ointment, and mupirocin had reduced bacterial growth compared to the positive control group, nanoparticle ointment, and silver sulfadiazine (P < 0.05). The wound area of the Myrtus ointment group decreased significantly on the seventh and fourteenth days, as well as the level of MDA and nitric oxide, compared to the other groups. In Myrtus and silver sulfadiazine-Myrtus ointment increased the thickness of the epidermis and dermis compared to the other groups. Conclusion: Based on the anti-inflammatory, antimicrobial, and wound healing properties of Myrtus, with further studies, an ointment of this plant may be used as a main or complementary treatment for burn wound infections caused by MRSA.


Subject(s)
Anti-Inflammatory Agents , Burns , Methicillin-Resistant Staphylococcus aureus , Myrtus , Ointments , Plant Extracts , Plant Leaves , Rats, Wistar , Wound Healing , Animals , Wound Healing/drug effects , Methicillin-Resistant Staphylococcus aureus/drug effects , Burns/drug therapy , Burns/microbiology , Plant Extracts/pharmacology , Male , Ointments/pharmacology , Rats , Anti-Inflammatory Agents/pharmacology , Plant Leaves/chemistry , Myrtus/chemistry , Anti-Infective Agents/pharmacology , Wound Infection/drug therapy , Wound Infection/microbiology , Staphylococcal Infections/drug therapy , Staphylococcal Infections/microbiology , Metal Nanoparticles/chemistry , Silver Sulfadiazine/pharmacology
19.
Nutrients ; 16(11)2024 May 24.
Article in English | MEDLINE | ID: mdl-38892531

ABSTRACT

Propolis has potential anti-inflammatory properties, but little is known about its efficacy against inflammatory reactions caused by drug-resistant bacteria, and the difference in efficacy between propolis and tree gum is also unclear. Here, an in vivo study was performed to study the effects of ethanol extract from poplar propolis (EEP) and poplar tree gum (EEG) against heat-inactivated methicillin-resistant Staphylococcus aureus (MRSA)-induced acute lung injury (ALI) in mice. Pre-treatment with EEP and EEG (100 mg/kg, p.o.) resulted in significant protective effects on ALI in mice, and EEP exerted stronger activity to alleviate lung tissue lesions and ALI scores compared with that of EEG. Furthermore, EEP significantly suppressed the levels of pro-inflammatory mediators in the lung, including TNF-α, IL-1ß, IL-6, and IFN-γ. Gut microbiota analysis revealed that both EEP and EEG could modulate the composition of the gut microbiota, enhance the abundance of beneficial microbiota and reduce the harmful ones, and partly restore the levels of short-chain fatty acids. EEP could modulate more serum metabolites and showed a more robust correlation between serum metabolites and gut microbiota. Overall, these results support the anti-inflammatory effects of propolis in the treatment of ALI, and the necessity of the quality control of propolis.


Subject(s)
Acute Lung Injury , Gastrointestinal Microbiome , Inflammation Mediators , Methicillin-Resistant Staphylococcus aureus , Propolis , Propolis/pharmacology , Animals , Methicillin-Resistant Staphylococcus aureus/drug effects , Acute Lung Injury/microbiology , Acute Lung Injury/drug therapy , Gastrointestinal Microbiome/drug effects , Mice , Male , Inflammation Mediators/blood , Inflammation Mediators/metabolism , Anti-Inflammatory Agents/pharmacology , Staphylococcal Infections/drug therapy , Cytokines/blood , Cytokines/metabolism , Hot Temperature , Disease Models, Animal
20.
Arch Microbiol ; 206(7): 288, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38834761

ABSTRACT

Bone infections caused by Staphylococcus aureus may lead to an inflammatory condition called osteomyelitis, which results in progressive bone loss. Biofilm formation, intracellular survival, and the ability of S. aureus to evade the immune response result in recurrent and persistent infections that present significant challenges in treating osteomyelitis. Moreover, people with diabetes are prone to osteomyelitis due to their compromised immune system, and in life-threatening cases, this may lead to amputation of the affected limbs. In most cases, bone infections are localized; thus, early detection and targeted therapy may prove fruitful in treating S. aureus-related bone infections and preventing the spread of the infection. Specific S. aureus components or overexpressed tissue biomarkers in bone infections could be targeted to deliver active therapeutics, thereby reducing drug dosage and systemic toxicity. Compounds like peptides and antibodies can specifically bind to S. aureus or overexpressed disease markers and combining these with therapeutics or imaging agents can facilitate targeted delivery to the site of infection. The effectiveness of photodynamic therapy and hyperthermia therapy can be increased by the addition of targeting molecules to these therapies enabling site-specific therapy delivery. Strategies like host-directed therapy focus on modulating the host immune mechanisms or signaling pathways utilized by S. aureus for therapeutic efficacy. Targeted therapeutic strategies in conjunction with standard surgical care could be potential treatment strategies for S. aureus-associated osteomyelitis to overcome antibiotic resistance and disease recurrence. This review paper presents information about the targeting strategies and agents for the therapy and diagnostic imaging of S. aureus bone infections.


Subject(s)
Anti-Bacterial Agents , Osteomyelitis , Staphylococcal Infections , Staphylococcus aureus , Osteomyelitis/microbiology , Osteomyelitis/drug therapy , Humans , Staphylococcus aureus/drug effects , Staphylococcus aureus/physiology , Staphylococcal Infections/drug therapy , Staphylococcal Infections/microbiology , Anti-Bacterial Agents/therapeutic use , Biofilms/drug effects , Animals
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