Complex Chronic Wound Biofilms Are Inhibited in vitro by the Natural Extract of Capparis spinose

The Challenges of The Diagnostic and Therapeutic Approach of Patients with Infectious Pathology in Emergency Medicine

The emergency department (ED) represents an important setting for addressing inappropriate antimicrobial prescribing practices because of the time constraints and the duration of microbiological diagnosis. The purpose of this study is to evaluate the etiology and antimicrobial resistance (AMR) pattern of the community-acquired pathogens, as well as the epidemiological characteristics of patients admitted through the ED, in order to guide appropriate antibiotic therapy.

METHODS

A retrospective observational study was performed on 657 patients, from whom clinical samples (urine, purulent secretions, blood cultures, etc.) were collected for microbiological diagnosis in the first 3 days after presentation in the ED. The identification of pathogens and the antimicrobial susceptibility testing with minimum inhibitory concentration determination were carried out according to the laboratory protocols.

RESULTS

From the 767 biological samples analyzed, 903 microbial isolates were identified. E. coli was most frequently isolated (24.25%), followed by Klebsiella spp., S. aureus (SA), and non-fermentative Gram-negative bacilli. E. coli strains maintained their natural susceptibility to most antibiotics tested. In the case of Pseudomonas spp. and Acinetobacter spp., increased rates of AMR were identified. Also, 32.3% of SA strains were community-acquired MRSA.

CONCLUSIONS

The introduction of rapid microbiological diagnostic methods in emergency medicine is imperative in order to timely identify AMR strains and improve therapeutic protocols.

Complex magnetic fields represent an eco-sustainable technology to counteract the resistant Candida albicans growth without affecting the human gingival fibroblasts

Novel technologies such as complex magnetic fields-CMFs represent an eco-sustainable proposal to counteract the infection associated to resistant microorganisms. The aim of this study was to evaluate the effect of two CMF programs (STRESS, ANTIBACTERIAL) against clinical antifungal resistant C. albicans also evaluating their uneffectiveness on gingival fibroblasts (hGFs). The STRESS program was more efficacious on C. albicans biofilm with up to 64.37% ± 10.80 of biomass and up to 99.19% ± 0.06 CFU/ml reductions in respect to the control also inducing an alteration of lipidic structure of the membrane. The MTT assay showed no CMFs negative effects on the viability of hGFs with a major ROS production with the ANTIBACTERIAL program at 3 and 24 h. For the wound healing assay, STRESS program showed the best effect in terms of the rate migration at 24 h, showing statistical significance of p < 0.0001. The toluidine-blue staining observations showed the typical morphology of cells and the presence of elongated and spindle-shaped with cytoplasmic extensions and lamellipodia was observed by SEM. The ANTIBACTERIAL program statistically increased the production of collagen with respect to control and STRESS program (p < 0.0001). CMFs showed a relevant anti-virulence action against C. albicans, no cytotoxicity effects and a high hGFs migration rate. The results of this study suggest that CMFs could represent a novel eco-sustainable strategy to counteract the resistant yeast biofilm infections.

Evaluation of the Antioxidant, Antimicrobial, and Anti-Biofilm Effects of the Stem Bark, Leaf, and Seed Extracts from Hymenaea courbaril and Characterization by UPLC-ESI-QTOF-MS/MS Analysis

Currently, biofilm-forming bacteria are difficult to treat by conventional antibiotic therapy and are, thus, becoming a clinical and epidemiological problem worldwide. Medicinal plants have been identified as novel alternative treatments due to their therapeutic and antimicrobial effects. In this context, the present study aimed to determine the total phenolic content, antioxidant capacity, and antimicrobial and anti-biofilm potential of nine extracts of Hymenaea courbaril (Fabaceae), popularly known as Jatobá. Furthermore, extracts that exhibited biofilm inhibitory activity against S. aureus (ATCC 25923) were selected for UPLC-HRMS/MS chemical analysis. Our results showed a high total phenolic content, mainly in the stem bark extract, and that the plant is rich in compounds with antioxidant activity. In the anti-biofilm analysis, leaf extracts stood out in comparison with chloramphenicol, with inhibition percentages of 78.29% and 78.85%, respectively. Through chemical analysis by UPLC-HRMS/MS, chrysoeriol-7-O-neohesperidoside, isorhamnetin-3-O-glucoside, and 3,7-di-O-methylquercetin were annotated for the first time in the leaves of H. courbaril. Therefore, these results showed the potential use of H. courbaril as an antioxidant and point to its use in antimicrobial therapy with an anti-biofilm effect.

The Antibacterial and Antifungal Capacity of Eight Commercially Available Types of Mouthwash against Oral Microorganisms: An In Vitro Study

This work aimed to evaluate and compare the antimicrobial actions and effects over time of eight types of mouthwash, based on the impact of chlorhexidine on the main microorganisms that are responsible for oral diseases: Enterococcus faecalis, Pseudomonas aeruginosa, and Candida albicans. The mouthwashes’ antimicrobial action was determined in terms of their minimum inhibitory concentration (MIC), minimum bactericidal/fungicidal concentration (MBC/MFC), and time-kill curves at different contact times (10 s, 30 s, 60 s, 5 min, 15 min, 30 min, and 60 min), against selected oral microorganisms. All the mouthwashes showed a notable effect against C. albicans (MICs ranging from 0.02% to 0.09%), and higher MIC values were recorded with P. aeruginosa (1.56% to >50%). In general, the mouthwashes showed similar antimicrobial effects at reduced contact times (10, 30, and 60 s) against all the tested microorganisms, except with P. aeruginosa, for which the most significant effect was observed with a long time (15, 30, and 60 min). The results demonstrate significant differences in the antimicrobial actions of the tested mouthwashes, although all contained chlorhexidine and most of them also contained cetylpyridinium chloride. The relevant antimicrobial effects of all the tested mouthwashes, and those with the best higher antimicrobial action, were recorded by A—GUM® PAROEX®A and B—GUM® PAROEX®, considering their effects against the resistant microorganisms and their MIC values.

Evaluation of Antimicrobial Properties and Potential Applications of Pseudomonas gessardii M15 Rhamnolipids towards Multiresistant Staphylococcus aureus

Staphylococcus aureus is a Gram-positive opportunistic human pathogen responsible for severe infections and thousands of deaths annually, mostly due to its multidrug-resistant (MDR) variants. The cell membrane has emerged as a promising new therapeutic target, and lipophilic molecules, such as biosurfactants, are currently being utilized. Herein, we evaluated the antimicrobial activity of a rhamnolipids mixture produced by the Antarctic marine bacterium Pseudomonas gessardii M15. We demonstrated that our mixture has bactericidal activity in the range of 12.5-50 µg/mL against a panel of clinical MDR isolates of S. aureus, and that the mixture eradicated the bacterial population in 30 min at MIC value, and in 5 min after doubling the concentration. We also tested abilities of RLs to interfere with biofilm at different stages and determined that RLs can penetrate biofilm and kill the bacteria at sub-MICs values. The mixture was then used to functionalize a cotton swab to evaluate the prevention of S. aureus proliferation. We showed that by using 8 µg of rhamnolipids per swab, the entire bacterial load is eradicated, and just 0.5 µg is sufficient to reduce the growth by 99.99%. Our results strongly indicate the possibility of using this mixture as an additive for wound dressings for chronic wounds.

Biofilms in Chronic Wound Infections: Innovative Antimicrobial Approaches Using the In Vitro Lubbock Chronic Wound Biofilm Model

Chronic wounds have harmful effects on both patients and healthcare systems. Wound chronicity is attributed to an impaired healing process due to several host and local factors that affect healing pathways. The resulting ulcers contain a wide variety of microorganisms that are mostly resistant to antimicrobials and possess the ability to form mono/poly-microbial biofilms. The search for new, effective and safe compounds to handle chronic wounds has come a long way throughout the history of medicine, which has included several studies and trials of conventional treatments. Treatments focus on fighting the microbial colonization that develops in the wound by multidrug resistant pathogens. The development of molecular medicine, especially in antibacterial agents, needs an in vitro model similar to the in vivo chronic wound environment to evaluate the efficacy of antimicrobial agents. The Lubbock chronic wound biofilm (LCWB) model is an in vitro model developed to mimic the pathogen colonization and the biofilm formation of a real chronic wound, and it is suitable to screen the antibacterial activity of innovative compounds. In this review, we focused on the characteristics of chronic wound biofilms and the contribution of the LCWB model both to the study of wound poly-microbial biofilms and as a model for novel treatment strategies.

Antimicrobial Combined Action of Graphene Oxide and Light Emitting Diodes for Chronic Wound Management

Innovative non-antibiotic compounds such as graphene oxide (GO) and light-emitting diodes (LEDs) may represent a valid strategy for managing chronic wound infections related to resistant pathogens. This study aimed to evaluate 630 nm LED and 880 nm LED ability to enhance the GO antimicrobial activity against Staphylococcus aureus- and Pseudomonas aeruginosa-resistant strains in a dual-species biofilm in the Lubbock chronic wound biofilm (LCWB) model. The effect of a 630 nm LED, alone or plus 5-aminolevulinic acid (ALAD)-mediated photodynamic therapy (PDT) (ALAD-PDT), or an 880 nm LED on the GO (50 mg/l) action was evaluated by determining the CFU/mg reductions, live/dead analysis, scanning electron microscope observation, and reactive oxygen species assay. Among the LCWBs, the best effect was obtained with GO irradiated with ALAD-PDT, with percentages of CFU/mg reduction up to 78.96% ± 0.21 and 95.17% ± 2.56 for S. aureus and P. aeruginosa, respectively. The microscope images showed a reduction in the cell number and viability when treated with GO + ALAD-PDT. In addition, increased ROS production was detected. No differences were recorded when GO was irradiated with an 880 nm LED versus GO alone. The obtained results suggest that treatment with GO irradiated with ALAD-PDT represents a valid, sustainable strategy to counteract the polymicrobial colonization of chronic wounds.