Biofilm and wound healing: from bench to bedside

Recent advancements in magnetic starch-based composites for biomedical applications: A review

The increasing demand for biomedical materials to address various diseases has highlighted the need for advanced biocompatible materials with improved biofunctionality for smart diagnostics and clinical therapies. Starch, a natural polymer, is an ideal starting material for the development of multifunctional biomedical materials due to its biocompatibility, low toxicity, and biodegradability. However, native starch lacks certain properties, particularly magnetic properties. By strategically modifying the structure of starch or its derivatives and incorporating different types of magnetic nanoparticles (MNPs), magnetic starch-based composites (MSBCs) can be developed. These composites take the advantages of both the magnetic materials and natural polysaccharides, enhancing the mechanical strength of starch and imparting additional properties, such as magneto-thermal effects, targeting ability, stimulus-responsive drug delivery, and easy separation. As a result, MSBCs have widespread applications in fields such as wound dressing and magneto-thermal therapy. This review highlights the types of MSBCs, their synthesis methods, and their current applications in biomedicine. Additionally, this review describes the major challenges faced by MSBCs in biomedical applications and provides an outlook on their potential for further development. This review aims to improve the understanding of magnetic starches and optimize their synthetic strategies, positioning MSBCs as promising platforms for biomedical applications.

Functional Amyloid Phenol-Soluble Modulin α1-Targeting Photothermal Nanoplatform for Effective Elimination of Biofilm-Associated Infections

Biofilm-associated infections (BAIs) often lead to chronic infections and implant failure and are challenging to treat due to their resilience and complex structure, especially the extracellular polymeric substance (EPS). Phenol-soluble modulin α1 (PSMα1), a key biofilm-forming protein in methicillin-resistant Staphylococcus aureus (MRSA), can assemble into amyloid fibrils through self/cross-fibrillation and thus function as a scaffold that contributes to the integrity of the biofilm matrix. Here, using a phage display library-based biopanning strategy, we identified KG7, a PSMα1-targeting peptide that binds specifically to the fibrillation-dependent sequence in PSMα1, significantly inhibiting the amyloid fibrillation of PSMα1 and the subsequent biofilm formation in vitro. Further, the KG7 peptide was conjugated to the surface of polydopamine (PDA)-modified hollow copper sulfide (CuS) nanoparticles to develop an EPS-targeting photothermal nanoplatform (CuS@PPDA). This nanoplatform achieved a 94.7% biofilm inhibition rate and cleared 56.8% of mature biofilms through the regulation of PSMα1 fibrillation and the destruction of extracellular DNA, thanks to the synergistic effect of KG7-mediated inhibition and photothermal capability. Additionally, Cu2+ release from the nanoplatform regulated macrophage polarization toward the M2 phenotype. In vivo studies also demonstrated that this nanoplatform significantly accelerated diabetic wound healing and prevented biofilm formation on implants, along with excellent antibacterial performance and tissue regeneration efficiency. This work introduces a proof-of-concept of photothermal nanoplatform targeting biofilm-scaffolding amyloid PSMα1, offering a promising treatment for BAIs.

SEMTWIST Quantification of Biofilm Infection in Human Chronic Wound Using Scanning Electron Microscopy and Machine Learning

Objective: To develop scanning electron microscopy-based Trainable Weka (Waikato Environment for Knowledge Analysis) Intelligent Segmentation Technology (SEMTWIST), an open-source software tool, for structural detection and rigorous quantification of wound biofilm aggregates in complex human wound tissue matrix. Approach: SEMTWIST model was standardized to quantify biofilm infection (BFI) abundance in 240 distinct SEM images from 60 human chronic wound-edge biospecimens (four technical replicates of each specimen). Results from SEMTWIST were compared against human expert assessments and the gold standard for molecular BFI detection, that is, peptide nucleic acid fluorescence in situ hybridization (PNA-FISH). Results: Correlation and Bland-Altman plot demonstrated a robust correlation (r = 0.82, p < 0.01), with a mean bias of 1.25, and 95% limit of agreement ranging from -43.40 to 47.11, between SEMTWIST result and the average scores assigned by trained human experts. While interexpert variability highlighted potential bias in manual assessments, SEMTWIST provided consistent results. Bacterial culture detected infection but not biofilm aggregates. Whereas the wheat germ agglutinin staining exhibited nonspecific staining of host tissue components and failed to provide a specific identification of BFI. The molecular identification of biofilm aggregates using PNA-FISH was comparable with SEMTWIST, highlighting the robustness of the developed approach. Innovation: This study introduces a novel approach "SEMTWIST" for in-depth analysis and precise differentiation of biofilm aggregates from host tissue elements, enabling accurate quantification of BFI in chronic wound SEM images. Conclusion: Open-source SEMTWIST offers a reliable and robust framework for standardized quantification of BFI burden in human chronic wound-edge tissues, supporting clinical diagnosis and guiding treatment.

Application of sodium alginate and polyethylene glycol bilayer multifunctional hydrogel microneedles in infectious and diabetic wounds

Chronic wounds are challenging to heal due to persistent infection, prolonged inflammation, and impaired angiogenesis, which can ultimately lead to severe disabilities. Current treatment strategies are unable to provide the comprehensive conditions needed for effective chronic wound healing. Herein, we proposed a multifunctional microneedle patch for chronic wound healing, consisting of a needle-like drug-loading gel (DG) constructed with polyethylene glycol (PEG) and a backing hydrogel (BHG) layer constructed with sodium alginate. This design combines the therapeutic effects of drug delivery with the protective benefits of a hydrogel. The needle-like DG layer effectively penetrates the bacterial biofilm, releasing Erythromycin, Vaccarin, Demethylsuberosin, and Cyanidin, agents with synergistic antibacterial, anti-inflammatory, pro-angiogenic, and antioxidant effects in a temperature response-dependent manner. Together, these components address multiple barriers to chronic wound healing. The DG layer also maintains a moist wound environment for the wound. The pH-responsive properties of Cyanidin visually indicate the wound healing status. The multifunctional microneedle patch (DG@BHG) significant enhances healing in both infected and diabetic wounds, leveraging the combined effects of drug action and hydrogel support. This approach presents a novel therapeutic strategy for chronic wound healing by addressing infection, inflammation, and angiogenesis simultaneously.

Enhancing patient outcomes: the role of octenidine-based irrigation solutions in managing sore and irritated peristomal skin

This article explores the potential benefits of cleansing damaged peristomal skin with an octenidine-based antimicrobial irrigation solution.

Nanomaterial-enabled anti-biofilm strategies: new opportunities for treatment of bacterial infections

Biofilms play a pivotal role in bacterial pathogenicity and antibiotic resistance, representing a major challenge in the treatment of bacterial infections. The limited diffusion and inactivation efficacy of antibiotics within biofilms hinder their clearance, and while increasing dosage may enhance effectiveness, it also promotes antibiotic resistance. Nano-delivery systems that target antimicrobial agents directly to biofilms offer a promising strategy to overcome this challenge. This review summarizes the resistance mechanisms and therapeutic challenges associated with biofilms, with a focus on recent advances in nano-delivery systems such as liposomes, nanoemulsions, cell membrane vesicles (CMVs), polymers, dendrimers, nanogels, inorganic nanoparticles, and metal-organic frameworks (MOFs). Furthermore, the review explores the potential applications and challenges of nano-delivery systems in biofilm treatment and provides recommendations to guide future research and development in this field.

Primary Ankle Fracture Dislocation Is Not a Negative Prognostic Factor for the Surgical Treatment of Syndesmotic Injury-A Retrospective Analysis of 246 Patients

Background/Objectives: Acute ankle sprains are common injuries that significantly affect both sports and daily activities. Syndesmotic injuries, a specific type of ligamentous damage, can occur as a part of a sprain or alongside fractures, affecting approximately 20% of ankle fractures. The aim of this study was to evaluate negative prognostic factors influencing surgical outcomes in tibiofibular syndesmotic injuries associated with ankle fractures. Methods: Data from 246 patients were analyzed to examine the impact of initial ankle dislocation, fracture type, and fixation method on postoperative complications and reoperation rates. Ankle joint fractures were treated with open reduction and internal fixation using an anatomically contoured plate designed for optimal tibia and fibula fixation. Four methods of syndesmosis fixation were recorded: one three-cortical screw, one four-cortical screw, two screws (either both four-cortex screws or one three-cortex and one four-cortex screw), or one endobutton. Data analysis was performed using SPSS version 25 (IBM Corp., Armonk, NY, USA). Results: Key findings reveal no significant association between initial dislocation and the necessity for reoperation (p = 0.613). However, smoking combined with dislocation significantly increases reoperation rates (35% vs. 15.5%, p = 0.026). Fixation type influenced outcomes, with single four-cortex screws linked to pain but fewer infections. Infection was the most common complication (33.3%), predominantly after fixation with a single three-cortex screw. Men had higher rates of fixation destabilization and infections, while women experienced pain persisting beyond six months postoperatively Conclusions: Patient-specific factors influence syndesmotic injury outcomes. Smoking, gender, and fixation type impact complications, emphasizing the need for tailored surgical approaches to enhance recovery and minimize reoperation risks. Future research should aim to corroborate these findings in larger, multicentric cohorts to refine surgical strategies for syndesmotic injury management.

Advancements in Wound Dressing Materials: Highlighting Recent Progress in Hydrogels, Foams, and Antimicrobial Dressings

Recent advancements in wound dressing materials have significantly improved acute and chronic wound management by addressing challenges such as infection control, moisture balance, and enhanced healing. Important progress has been made, especially with hydrogels, foams, and antimicrobial materials for creating optimized dressings. Hydrogels are known for maintaining optimal moisture levels, while foam dressings are excellent exudate absorbents. Meanwhile, antimicrobial dressing incorporates various antimicrobial agents to reduce infection risks. These dressing options reduce wound healing time while focusing on customized patient needs. Therefore, this review highlights the newest research materials and prototypes for wound healing applications, emphasizing their particular benefits and clinical importance. Innovations such as stimuli-responsive hydrogels and hybrid bioengineered composites are discussed in relation to their enhanced properties, including responsiveness to pH, temperature, glucose, or enzymes and drug delivery precision. Moreover, ongoing clinical trials have been included, demonstrating the potential of emerging solutions to be soon translated from the laboratory to clinical settings. By discussing interdisciplinary approaches that integrate advanced materials, nanotechnology, and biological insights, this work provides a contemporary framework for patient-centric, efficient wound care strategies.

Antimicrobial Blue Light Reduces Human-Wound Pathogens' Resistance to Tetracycline-Class Antibiotics in Biofilms

Biofilms contribute to chronic infections and the development of antimicrobial resistance (AMR). We are developing an antimicrobial blue light (aBL) device to reduce bacterial bioburden in wounds and decrease reliance on systemic antibiotics. aBL induces the generation of reactive oxygen species (ROS) through photoexcitation of endogenous chromophores, causing bacterial damage and death. This study explores the combination of tetracyclines (TCs) with aBL for the treatment of biofilm infections in vitro. Tetracyclines (TCs), including second-generation minocycline (MC), doxycycline (DOCT), and third-generation agents omadacycline (OM) and tigecycline (TG), were evaluated for their ability to enhance bactericidal effects and ROS production during aBL treatment of abiotic biofilm. TCs were tested under dark conditions and with varying aBL light parameters against biofilms of methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa (PA), and Escherichia coli (E. coli). Results showed that TCs alone were ineffective against these biofilm cultures. However, when combined with aBL either before or after TC treatment, significant enhancement of microbicidal activity was observed. When the aBL is added before the TCs, there was equivalent bactericidal effect, indicating that TCs primary action against biofilms were not as photosensitizers. These findings suggest that aBL can significantly enhance the antimicrobial activity of TCs, potentially offering a new effective approach to treating biofilm-associated infections and combating AMR when aBL is applicable.

A review on multifunctional calcium alginate fibers for full-time and multipurposed wound treatment: From fundamentals to advanced applications

Recent progress in wound healing has highlighted the need for more effective treatment strategies capable of addressing the complex biological and physiological challenges of wound repair. Traditional wound dressings often fail to address the complex and evolving needs of chronic, acute, and burn wounds, particularly in terms of promoting healing, preventing infection, and supporting tissue regeneration. In response to these challenges, calcium alginate fibers (CAFs) have emerged as promising materials, characterized by their exceptional structural properties and diverse biological functions, offering significant commercial potential for the development of advanced wound dressings and therapeutic solutions. Here, a brief review of the CAFs for promoting wound healing is presented, with specific discussions of the fundamental characteristics of CAFs and its feasibility to be applied for adjusting physiological and pathological processes involved in wound healing. Then, a comprehensive and in-depth depiction of emerging representative fabrication techniques for generating CAFs is categorized and reviewed. Moreover, emerging applications benefits from the CAFs are reviewed, highlighting the multifunctional roles and benefits of CAFs in facilitating wound repair. Finally, the challenges and perspectives for further advancing CAFs toward a more powerful and versatile therapeutic strategy are discussed, particularly regarding new opportunities in biomedical research and clinical applications.

Empirical use, phytochemical, and pharmacological effects in wound healing activities of compounds in Diospyros leaves: A review of traditional medicine for potential new plant-derived drugs

ETHNOPHARMACOLOGICAL RELEVANCE

Wound healing extracts' activity is increasingly being studied in the field of traditional medicine. Among medicinal plants, Diospyros is known to have healing effects on wounds, along with activities such as anti-biofilm, anti-inflammatory, antibacterial, antioxidant, and regulation of the immune system. However, the current use of the leaves could be more optimal, and the scientific basis needs to be improved.

AIM OF THIS REVIEW

This review aimed to critically examine the literature on the traditional use and bioactive metabolites of several Diospyros species, demonstrating the significant potential in wound healing, antibacterial, anti-biofilm, regulatory effect on the immune system, anti-inflammatory, and antioxidant activities. The critical analysis was conducted to provide robust perspectives and recommendations for future studies on the use of Diospyros potential resources of wound healing material, including related activities.

MATERIALS AND METHODS

Exploratory studies on Diospyros species over the past 20 years were examined, with a focus on general information, practical use, secondary metabolite, and pharmacological activities related to wound healing. Data were meticulously collected from scientific databases including Scopus, ScienceDirect, Web of Science, Taylor & Francis, Google Scholar, PubMed as well as various botanical and biodiversity sources. Furthermore, manual searches were conducted to ensure comprehensive coverage. Reference manager software was used to manage articles and remove duplicates, then the gathered data were summarized and verified, ensuring the thoroughness and validity of the review process.

RESULTS

The results showed that Diospyros leaves have great potential to be harnessed as herbal medications, evidenced by both scientific findings and community uses. Various substances, including flavonoids, coumarins, tannins, terpenoids, steroids, lignans, quinones, and secoiridoids were identified. Chemical compound investigations in both in vivo and in vitro studies of Diospyros leaves reported wound healing activity, as well as antibacterial, anti-inflammatory, anti-biofilm, antioxidant, and immunomodulatory properties.

CONCLUSION

The review highlights the traditional uses and bioactive metabolites of Diospyros species in wound healing, identifying various beneficial compounds such as flavonoids and tannins. These compounds demonstrate various therapeutic effects, including antibacterial, anti-biofilm, anti-inflammatory, antioxidant, and immunomodulatory activities. Diospyros leaf extracts have a favorable safety profile, but further studies, including in vivo investigations and clinical trials, are necessary to confirm their efficacy and safety for clinical applications. Diospyros leaf extracts have significant potential for the development of wound healing substances due to the wide range of bioactivities targeting various stages of wound healing.

Molecular Modification of Queen Bee Acid and 10-Hydroxydecanoic Acid with Specific Tripeptides: Rational Design, Organic Synthesis, and Assessment for Prohealing and Antimicrobial Hydrogel Properties

Royal jelly and medical grade honey are traditionally used in treating wounds and infections, although their effectiveness is often variable and insufficient. To overcome their limitations, we created novel amphiphiles by modifying the main reparative and antimicrobial components, queen bee acid (hda) and 10-hydroxyl-decanoic acid (hdaa), through peptide bonding with specific tripeptides. Our molecular design incorporated amphiphile targets as being biocompatible in wound healing, biodegradable, non-toxic, hydrogelable, prohealing, and antimicrobial. The amphiphilic molecules were designed in a hda(hdaa)-aa1-aa2-aa3 structural model with rational selection criteria for each moiety, prepared via Rink/Fmoc-tBu-based solid-phase peptide synthesis, and structurally verified by NMR and LC-MS/MS. We tested several amphiphiles among those containing moieties of hda or hdaa and isoleucine-leucine-aspartate (ILD-amidated) or IL-lysine (ILK-NH2). These tests were conducted to evaluate their prohealing and antimicrobial hydrogel properties. Our observation of their hydrogelation and hydrogel-rheology showed that they can form hydrogels with stable elastic moduli and injectable shear-thinning properties, which are suitable for cell and tissue repair and regeneration. Our disc-diffusion assay demonstrated that hdaa-ILK-NH2 markedly inhibited Staphylococcus aureus. Future research is needed to comprehensively evaluate the prohealing and antimicrobial properties of these novel molecules modified from hda and hdaa with tripeptides.

Unveiling the nanoworld of antimicrobial resistance: integrating nature and nanotechnology

A significant global health crisis is predicted to emerge due to antimicrobial resistance by 2050, with an estimated 10 million deaths annually. Increasing antibiotic resistance necessitates continuous therapeutic innovation as conventional antibiotic treatments become increasingly ineffective. The naturally occurring antibacterial, antifungal, and antiviral compounds offer a viable alternative to synthetic antibiotics. This review presents bacterial resistance mechanisms, nanocarriers for drug delivery, and plant-based compounds for nanoformulations, particularly nanoantibiotics (nAbts). Green synthesis of nanoparticles has emerged as a revolutionary approach, as it enhances the effectiveness, specificity, and transport of encapsulated antimicrobials. In addition to minimizing systemic side effects, these nanocarriers can maximize therapeutic impact by delivering the antimicrobials directly to the infection site. Furthermore, combining two or more antibiotics within these nanoparticles often exhibits synergistic effects, enhancing the effectiveness against drug-resistant bacteria. Antimicrobial agents are routinely obtained from secondary metabolites of plants, including essential oils, phenols, polyphenols, alkaloids, and others. Integrating plant-based antibacterial agents and conventional antibiotics, assisted by suitable nanocarriers for codelivery, is a potential solution for addressing bacterial resistance. In addition to increasing their effectiveness and boosting the immune system, this synergistic approach provides a safer and more effective method of tackling future bacterial infections.

Biochemistry of Bacterial Biofilm: Insights into Antibiotic Resistance Mechanisms and Therapeutic Intervention

Biofilms, composed of structured communities of bacteria embedded in a self-produced extracellular matrix, pose a significant challenge due to their heightened resistance to antibiotics and immune responses. This review highlights the mechanisms underpinning antibiotic resistance within bacterial biofilms, elucidating the adaptive strategies employed by microorganisms to withstand conventional antimicrobial agents. This encompasses the role of the extracellular matrix, altered gene expression, and the formation of persister cells, contributing to the recalcitrance of biofilms to eradication. A comprehensive understanding of these resistance mechanisms provides a for exploring innovative therapeutic interventions. This study explores promising avenues for future research, emphasizing the necessity of uncovering the specific genetic and phenotypic adaptations occurring within biofilms. The identification of vulnerabilities in biofilm architecture and the elucidation of key biofilm-specific targets emerge as crucial focal points for the development of targeted therapeutic strategies. In addressing the limitations of traditional antibiotics, this review discusses innovative therapeutic approaches. Nanomaterials with inherent antimicrobial properties, quorum-sensing inhibitors disrupting bacterial communication, and bacteriophages as biofilm-specific viral agents are highlighted as potential alternatives. The exploration of combination therapies, involving antimicrobial agents, biofilm-disrupting enzymes, and immunomodulators, is emphasized to enhance the efficacy of existing treatments and overcome biofilm resilience.

Local Treatment of Wound Infections: A Review of Clinical Trials from 2013 to 2024

Significance: Management of infection is a critical aspect of wound care. It involves the application of various interventions to treat the wound and prevent the infection from spreading to other parts of the body, which may lead to serious complications, including sepsis. Local treatment of skin wound infections is the favored route of administration, reducing the risk of adverse systemic effects while providing very high therapeutic concentrations at the target site. The purpose of this article was to review clinical trials from 2013 and onward, focusing on local treatment of acute wounds and burns as well as chronic wounds as their primary outcome measurement. Recent Advances: Based on our literature search, 49 clinical trials were focusing on treating infected chronic wounds, and 6 trials studied infection as their primary outcome in acute wounds during the last 10 years. Critical Issues: Currently commercially available local treatments do not prevent the onset of invasive infection. Therefore, there is a need for more effective local therapies. Future Directions: Despite multiple preclinical studies introducing novel and promising strategies in terms of novel antimicrobial agents and delivery methods to prevent and treat skin wound infections locally, many have yet to be tested in a clinical setting. These preclinically tested approaches could still be valuable additions to today's care of infected skin wounds.

RF pulsed plasma modified composite scaffold for enhanced anti-microbial activity and accelerated wound healing

Infected wounds present significant challenges pertaining to healing and often demand administration of strong antibiotics to patients. Also, drug resistant microbes may alter the physiology of wounds to create biofilms, frequently leading to high morbidity and mortality. In this investigation, a biodegradable, microporous composite agarose-chitosan scaffold was fabricated. Furthermore, its surface was modified with diphenyldiselenide deposition, using low pressure pulsed plasma technology. The optimized plasma parameters, viz. 5ON/15OFF (ms) of plasma pulse rate and 80 min of treatment time resulted in scaffolds having enhanced anti-bacterial activity against gram positive microbes like Staphylococcus (S.) aureus and S. epidermidis. The scaffolds were non-toxic to skin cells, as confirmed by the MTT assay. Cell proliferation through plasma treated and untreated scaffolds was assessed by culturing primary human dermal fibroblasts (HdaF) and human keratinocytes (HaCaT) and visualizing via confocal microscopy. Moreover, in-vivo rat model confirmed accelerated wound healing with plasma treated scaffold (100 % on day 14), as compared to the untreated scaffold (100 % on day 16) when compared with over-the-counter (OTC) ointment Betadine (100 % on day 12).

Clinical Presentation and Integrated Management of Pressure Injuries in the Emergency Hospital Setting: A Plastic Surgeon's Perspective

Background: Pressure injuries are localized areas of tissue damage or necrosis that occur when pressure is applied to the skin for prolonged periods, often over bony prominences, often the sacrum, heels, ischial tuberosities, and greater trochanters. The pathophysiology is complex, involving a combination of mechanical forces, ischemia, and tissue hypoxia. Methods: We conducted a 2-year retrospective study aiming to assess the clinical characteristics, risk factors, and management of pressure injuries in patients admitted to an emergency hospital who underwent a plastic surgery examination. Results: This study included 176 patients with clinically diagnosed pressure ulcers, with findings showing 28.52% of cases as stage III and 35.57% as stage IV. Common sites included the sacrum (40.94%), ischium (15.1%), and heel (14.43%). The median patient age was 76 years, with 47.15% between 60 and 80 years and 36.93% ≥ 80 years, often presenting with comorbidities increasing the risk of pressure injuries, such as cardiovascular disease (71.59%), diabetes (18.18%) and obesity (9.66%). Important risk factors included neurological diseases (46.02%), spinal cord injuries (14.7%), and nutritional deficiencies, as indicated by anemia (10.43g/dL; 95% CI [10.04; 10.82]), low serum albumin (2.56 g/dL; 95% CI [2.43; 2.69]) and proteins (5.54 g/dL; 95% CI [5.34; 5.73]). Mortality was significant, at 36.93%, with 23.3% occurring within the first 7 days of hospitalization due to the patients' critical condition. Decision-making for surgical intervention considered the patient's general status, comorbidities, and ulcer severity. Surgical treatment consisted of seriate debridement, negative pressure vacuum therapy, and/or coverage using skin grafting, local advancement, or rotation flaps. Conclusions: The key question for a plastic surgeon to consider is how pressure ulcers should be managed. Various debridement and covering techniques should be tailored to the wound's characteristics, considering patient comorbidities and general health condition.

Capturing the micro-communities: Insights into biogenesis and architecture of bacterial biofilms

Biofilm is an assemblage of microorganisms embedded within the extracellular matrix that provides mechanical stability, nutrient absorption, antimicrobial resistance, cell-cell interactions, and defence against host immune system. Various biomolecules such as lipids, carbohydrates, protein polymers (amyloid), and eDNA are present in the matrix playing significant role in determining the distinctive properties of biofilm. The formation of biofilms contributes to resistance against antimicrobial therapy in most of the human infections and exacerbates existing diseases. Therefore, this field requires several state-of-the-art techniques to fully understand the 3-D organization of biofilms, their cell behaviour and responses to pharmaceutical treatments. Here, we explore the assembly and regulation of biofilm biogenesis in the context of matrix components and highlight the significance of high-resolution imaging and analysing techniques for monitoring complex biofilm architecture. Our review also emphasizes the novelty and advancements in techniques to visualise biofilm structure and composition, providing valuable insights to understand biofilm-related infections.

H2Se-evolving bio-heterojunctions promote cutaneous regeneration in infected wounds by inhibiting excessive cellular senescence

Pathogenic infection leads to excessive senescent cell accumulation and stagnation of wound healing. To address these issues, we devise and develop a hydrogen selenide (H2Se)-evolving bio-heterojunction (bio-HJ) composed of graphene oxide (GO) and FeSe2 to deracinate bacterial infection, suppress cellular senescence and remedy recalcitrant infected wounds. Excited by near-infrared (NIR) laser, the bio-HJ exerts desired photothermal and photodynamic effects, resulting in rapid disinfection. The crafted bio-HJ could also evolve gaseous H2Se to inhibit cellular senescence and dampen inflammation. Mechanism studies reveal the anti-senescence effects of H2Se-evolving bio-HJ are mediated by selenium pathway and glutathione peroxidase 1 (GPX1). More critically, in vivo experiments authenticate that the H2Se-evolving bio-HJ could inhibit cellular senescence and potentiate wound regeneration in rats. As envisioned, our work not only furnishes the novel gasotransmitter-delivering bio-HJ for chronic infected wounds, but also gets insight into the development of anti-senescence biomaterials.

Effect of Alkanna tinctoria Root Against MRSA and MDR-Pseudomonas aeruginosa Biofilms on Excision Wound in Diabetic Mice: Comparative Study Between Methanolic Extract and Traditional Hydrophobic Preparation

Alkanna tinctoria, commonly called dyer's alkanet (family-Boraginaceae), is used traditionally in Saudi Arabia to treat skin infections. A methanolic extract and a traditional formulation of the root used in folklore were prepared. LC-MS analysis was conducted to identify probable compounds present in the extract and the traditional hydrophobic formulation. The in vivo activity on excision wound was evaluated in diabetic mice while crystal violet assay was employed for in vitro evaluation. Human keratinocyte (HaCaT) cells were used to study in vitro cytotoxic effects. Several probable phytoconstituents were revealed by LC-MS analysis in the methanolic extract and the traditional formulation, and three of the constituents were the same. The extract ointment and traditional hydrophobic extract exhibited antibacterial and antibiofilm activity against both tested pathogens. The methanolic extract was relatively more cytotoxic on HaCaT cells compared to the hydrophobic formulation. The methanolic extract ointment did not significantly affect the wound healing, whereas the traditional formulation accelerated wound healing in diabetic mice. The results revealed that A. tinctoria in its traditional formulation is an effective wound healing agent but the methanolic extract of the plant does not affect the healing of wounds.

Negative pressure therapy in pediatric patient with surgical site infection: experience report

OBJECTIVE

To describe the use of negative pressure wound therapy and hydrofiber dressing with silver in a pediatric patient with a hard-to-heal surgical wound infection.

METHOD

This is a descriptive professional experience report on the use of conventional dressings and negative pressure wound therapy in a pediatric patient with a surgical wound infection. It was developed in 2023 at a Public Health Service that is a reference in the care of pediatric patients in the state of Paraná.

RESULTS

The surgical wound dehiscence started 12 days after peritoneostomy. Initially, the wound was treated with hydrofiber dressing with silver for 22 days and subsequently, negative pressure wound therapy was used for 15 days, regenerating the wound.

CONCLUSION

Negative pressure wound therapy in pediatrics proved to be safe, effective and efficient for the treatment of complex wounds and corroborated the skin regeneration process, as did hydrofiber dressing with silver.

Endogenous/exogenous stimuli‐responsive smart hydrogels for diabetic wound healing

Diabetes significantly impairs the body's wound‐healing capabilities, leading to chronic, infection‐prone wounds. These wounds are characterized by hyperglycemia, inflammation, hypoxia, variable pH levels, increased matrix metalloproteinase activity, oxidative stress, and bacterial colonization. These complex conditions complicate effective wound management, prompting the development of advanced diabetic wound care strategies that exploit specific wound characteristics such as acidic pH, high glucose levels, and oxidative stress to trigger controlled drug release, thereby enhancing the therapeutic effects of the dressings. Among the solutions, hydrogels emerge as promising due to their stimuli‐responsive nature, making them highly effective for managing these wounds. The latest advancements in mono/multi‐stimuli‐responsive smart hydrogels showcase their superiority and potential as healthcare materials, as highlighted by relevant case studies. However, traditional wound dressings fall short of meeting the nuanced needs of these wounds, such as adjustable adhesion, easy removal, real‐time wound status monitoring, and dynamic drug release adjustment according to the wound's specific conditions. Responsive hydrogels represent a significant leap forward as advanced dressings proficient in sensing and responding to the wound environment, offering a more targeted approach to diabetic wound treatment. This review highlights recent advancements in smart hydrogels for wound dressing, monitoring, and drug delivery, emphasizing their role in improving diabetic wound healing. It addresses ongoing challenges and future directions, aiming to guide their clinical adoption.

An In Vitro Artificial Wound Slough-Biofilm Model Developed for Evaluating a Novel Antibiofilm Technology

Eschar and slough in wounds serve as a reservoir for microorganisms and biofilms, damaged/devitalised cells, and inflammatory chemokines/cytokines, which work to initiate and prolong persistent inflammation and increase the risk of infection. Biofilm-related inflammation and infections are considered to be highly prevalent in acute wounds and chronic wounds. As slough is known to harbour biofilms, measuring the efficacy of antimicrobials in killing microbes both within and under slough is warranted. This highlights the need for more clinically relevant wound biofilm models to address this significant clinical need. Consequently, in this study, we developed an in vitro artificial wound slough (AWS) biofilm model produced by forming a biofilm below a layer of AWS, the latter of which was composed of the main protein components reported in wound eschar and slough, namely collagen, elastin, and fibrin. The model was employed to investigate the antibiofilm and antibacterial efficacy of a new patented smart next-generation antibiofilm technology composed of silver-zinc EDTA complexes and designed as a family of multifunctional metal complexes referred to as MMCs, in a liquid format, and to determine both the performance and penetration through AWS to control and manage biofilms. The results demonstrated the ability of the AWS-biofilm model to be employed for the evaluation of the efficacy of a new antibiofilm and antimicrobial next-generation smart technology. The results also demonstrated the potential for the proprietary EDTA multifunctional metal complexes to be used for the disruption of biofilms, such as those that form in chronic wounds.

Combating antimicrobial resistance in osteoarticular infections: Current strategies and future directions

The emergence of antimicrobial resistance (AMR) has profoundly impacted the management of osteoarticular infections (OAIs), presenting significant challenges for healthcare systems worldwide. This review provides a comprehensive overview of the current landscape of AMR in OAIs, emphasizing the necessity for assertive and innovative strategies to combat this escalating health threat. It discusses the evolution of resistance among key pathogens, including ESKAPEE organisms, and the implications for treatment protocols and healthcare outcomes. The importance of antibiotic stewardship programs (ASPs) is highlighted as a core strategy to optimize antibiotic use and mitigate the development of resistance. Additionally, the review explores the potential of pharmacological approaches, including novel antibiotic regimens and combination therapies, alongside surgical interventions and alternative therapies such as bacteriophage-based treatments and probiotics, in managing these complex infections. The role of rapid diagnostic methods in improving treatment accuracy and the critical need for global surveillance to track AMR trends are also examined. By integrating insights from recent literature and expert recommendations, this review underscores the multifaceted approach required to address the challenge of AMR in OAIs effectively. It calls for a concerted effort among clinicians, researchers, and policymakers to foster innovation in treatment strategies, enhance diagnostic capabilities, and implement robust stewardship and surveillance programs. The goal is to adapt to the evolving landscape of OAIs and ensure optimal patient care in the face of rising AMR.

Optimising wound healing: the role of gelling fibre technology and antimicrobial silver nanoparticles

Gelling-fibre dressings have been found to be a rapid and effective tool for exudate management. Suprasorb Liquacel Pro is a soft, conformable non-woven dressing made from sodium carboxymethyl cellulose and strengthening cellulose fibres. When it comes into contact with wound exudate or blood, the absorbent dressing forms a gel, creating a moist wound environment. Cell debris and bacteria in the exudate are retained inside the fibre dressing and removed during the dressing change. The high vertical absorption of exudate into the fibre dressing protects the wound environment and the wound edge, thus supporting the healing process. Suprasorb Liquacel Ag has additional antimicrobial abilities with the inclusion of nanosilver technology, shown to be effective in killing bacteria and managing bioburden.

Accelerated healing of intractable biofilm-infected diabetic wounds by trypsin-loaded quaternized chitosan hydrogels that disrupt extracellular polymeric substances and eradicate bacteria

Complex and stubborn bacterial biofilm infections significantly hinder diabetic wound healing and threaten public health. Therefore, a dressing material that effectively clears biofilms and promotes wound healing is urgently required. Herein, we introduce a novel strategy for simultaneously dispersing extracellular polymeric substances and eradicating drug-resistant bacteria. We prepared an ultrabroad-spectrum and injectable quaternized chitosan (QCS) hydrogel loaded with trypsin, which degrades biofilm extracellular proteins. Increased temperature initiated QCS gelation to form the hydrogel, enabling the sustained release of trypsin and effective adherence of the hydrogel to irregularly shaped wounds. To reproduce clinical scenarios, biofilms formed by a mixture of Staphylococcus aureus (S. aureus), Methicillin-resistant S. aureus, and Pseudomonas aeruginosa were administered to the wounds of rats with streptozotocin-induced diabetes. Under these severe infection conditions, the hydrogel efficiently suppressed inflammation, promoted angiogenesis, and enhanced collagen deposition, resulting in accelerated healing of diabetic wounds. Notably, the hydrogel demonstrates excellent biocompatibility without cytotoxicity. In summary, we present a trypsin-loaded QCS hydrogel with tremendous clinical applications potential for the treatment of chronic infected wounds.

Assessing Biofilm at the Bedside: Exploring Reliable Accessible Biofilm Detection Methods

INTRODUCTION

Biofilm is linked through a variety of mechanisms to the pathogenesis of chronic wounds. However, accurate biofilm detection is challenging, demanding highly specialized and technically complex methods rendering it unapplicable for most clinical settings. This study evaluated promising methods of bedside biofilm localization, fluorescence imaging of wound bacterial loads, and biofilm blotting by comparing their performance against validation scanning electron microscopy (SEM).

METHODS

In this clinical trial, 40 chronic hard-to-heal wounds underwent the following assessments: (1) clinical signs of biofilm (CSB), (2) biofilm blotting, (3) fluorescence imaging for localizing bacterial loads, wound scraping taken for (4) SEM to confirm matrix encased bacteria (biofilm), and (5) PCR (Polymerase Chain Reaction) and NGS (Next Generation Sequencing) to determine absolute bacterial load and species present. We used a combination of SEM and PCR microbiology to calculate the diagnostic accuracy measures of the CSB, biofilm blotting assay, and fluorescence imaging.

RESULTS

Study data demonstrate that 62.5% of wounds were identified as biofilm-positive based on SEM and microbiological assessment. By employing this method to determine the gold truth, and thus calculate accuracy measures for all methods, fluorescence imaging demonstrated superior sensitivity (84%) and accuracy (63%) compared to CSB (sensitivity 44% and accuracy 43%) and biofilm blotting (sensitivity 24% and accuracy 40%). Biofilm blotting exhibited the highest specificity (64%), albeit with lower sensitivity and accuracy. Using SEM alone as the validation method slightly altered the results, but all trends held constant.

DISCUSSION

This trial provides the first comparative assessment of bedside methods for wound biofilm detection. We report the diagnostic accuracy measures of these more feasibly implementable methods versus laboratory-based SEM. Fluorescence imaging showed the greatest number of true positives (highest sensitivity), which is clinically relevant and provides assurance that no pathogenic bacteria will be missed. It effectively alerted regions of biofilm at the point-of-care with greater accuracy than standard clinical assessment (CSB) or biofilm blotting paper, providing actionable information that will likely translate into enhanced therapeutic approaches and better patient outcomes.

Synthesis and Characterization of Multifunctional Chitosan-Silver Nanoparticles: An In-Vitro Approach for Biomedical Applications

Antibiotics are successful in promoting health quality by preventing various infectious diseases and minimizing mortality and morbidity all over the world. However, the indiscriminate use of antibiotics has led to the emergence of multi-drug-resistant bacteria, which pose a serious threat to health care sector. Therefore, it is necessary to develop novel antimicrobial agents with versatile characteristics, such as antibacterial activity, low toxicity, wound healing potency, and antioxidant property. In this context, silver chitosan nanoparticles were synthesized in the present study, and their physical characterization revealed that the size of synthesized chitosan-silver nanoparticles was 14-25 nm, with positive surface charge. The functional groups and crystalline nature of the nanoparticles were confirmed by FT-IR and XRD analysis. Further, the silver chitosan nanoparticles showed antibacterial activity against two important clinical pathogens, S. aureus and E. coli. The MTT assay carried out in the present study showed that the synthesized nanoparticles are non-toxic to host cells. A scratch assay on fibroblast cells (L292) demonstrated that the silver chitosan nanoparticles showed promising wound healing activity. A fluorescent DCFH-DA staining assay revealed anantioxidant property of the synthesized nanoparticles. Overall, the study emphasizes the versatile nature of synthesized chitosan-silver nanoparticles, suggesting their great compatibility for biomedical applications.

Innovative approaches to wound healing: insights into interactive dressings and future directions

The objective of this review is to provide an up-to-date and all-encompassing account of the recent advancements in the domain of interactive wound dressings. Considering the gap between the achieved and desired clinical outcomes with currently available or under-study wound healing therapies, newer more specific options based on the wound type and healing phase are reviewed. Starting from the comprehensive description of the wound healing process, a detailed classification of wound dressings is presented. Subsequently, we present an elaborate and significant discussion describing interactive (unconventional) wound dressings. Latter includes biopolymer-based, bioactive-containing and biosensor-based smart dressings, which are discussed in separate sections together with their applications and limitations. Moreover, recent (2-5 years) clinical trials, patents on unconventional dressings, marketed products, and other information on advanced wound care designs and techniques are discussed. Subsequently, the future research direction is highlighted, describing peptides, proteins, and human amniotic membranes as potential wound dressings. Finally, we conclude that this field needs further development and offers scope for integrating information on the healing process with newer technologies.

Deep and Superficial Debridement Techniques in Lower Extremity Split-thickness Skin Grafting

Background

Patients with nonhealing lower extremity (LE) wounds often require a split-thickness skin graft (STSG) for closure. Nonviable tissue must be debrided before STSG inset. Our study aimed to compare differences in debridement depth on STSG outcomes.

Methods

Chronic, atraumatic LE wounds receiving STSG from December 2014 to December 2022 at a single institution were reviewed. Demographics, wound characteristics, operative details, and outcomes were collected. Superficially debrided wounds were compared with wounds receiving deep debridement (DD), defined by debriding to the level of white tissue underlying the granulation tissue. Subanalysis was performed on wounds that had a negative and positive postdebridement culture. Primary outcome was graft failure.

Results

Overall, 244 wounds in 168 patients were identified. In total, 158 (64.8%) wounds were superficially debrided and 86 (35.3%) received DD. The cohort had a median Charlson Comorbidity Index of 4 [interquartile range (IQR): 3]. Diabetes (56.6%) and peripheral artery disease (36.9%) were prevalent. The only statically significant demographic difference between groups was congestive heart failure (SD: 14.9% versus DD: 3.0%, P = 0.017). Wound size, depth, and all microbiology results were similar between groups. Postoperatively, the DD group demonstrated significantly less graft failure (10.5% versus 22.2%, P = 0.023). In a multivariate regression, DD was independently associated with lower odds of graft failure (OR: 0.0; CI, 0.0-0.8; P = 0.034). Sub-analysis of graft failure supported this finding in culture-positive wounds (DD: 7.6% versus DD: 22.1%, P = 0.018) but not in culture-negative wounds (13.6% versus 22.2%, P = 0.507).

Conclusions

The DD technique demonstrates improved outcomes in chronic, culture-positive LE wounds receiving STSG.

Nanoformulations for dismantling fungal biofilms: The latest arsenals of antifungal therapy

Globally, fungal infections have evolved as a strenuous challenge for clinicians, particularly in patients with compromised immunity in intensive care units. Fungal co-infection in Covid-19 patients has made the situation more formidable for healthcare practitioners. Surface adhered fungal population known as biofilm often develop at the diseased site to elicit antifungal tolerance and recalcitrant traits. Thus, an innovative strategy is required to impede/eradicate developed biofilm and avoid the formation of new colonies. The development of nanocomposite-based antibiofilm solutions is the most appropriate way to withstand and dismantle biofilm structures. Nanocomposites can be utilized as a drug delivery medium and for fabrication of anti-biofilm surfaces capable to resist fungal colonization. In this context, the present review comprehensively described different forms of nanocomposites and mode of their action against fungal biofilms. Amongst various nanocomposites, efficacy of metal/organic nanoparticles and nanofibers are particularly emphasized to highlight their role in the pursuit of antibiofilm strategies. Further, the inevitable concern of nanotoxicology has also been introduced and discussed with the exigent need of addressing it while developing nano-based therapies. Further, a list of FDA-approved nano-based antifungal formulations for therapeutic usage available to date has been described. Collectively, the review highlights the potential, scope, and future of nanocomposite-based antibiofilm therapeutics to address the fungal biofilm management issue.

Enhanced applications in dentistry through autoclave-assisted sonochemical synthesis of Pb/Ag/Cu trimetallic nanocomposites

In recent years, researchers have increasingly focused on the development of multiphase trimetallic nanocomposites (TMNC) incorporating ternary metals or metal oxides, which hold significant potential as alternatives for combatting biofilms and bacterial infections. Enhanced oral health is ensured by the innovative techniques used to effectively prevent bacterial adherence and formation of biofilm on dental sutures. In this investigation, TMNC, which consists of Pb, Ag, and Cu, was synthesized using an autoclave-assisted sonochemical technique. Following synthesis, TMNC were characterized using FTIR, XRD, BET, XPS, TGA, and Raman spectroscopy to analyze their shape and microstructure. Subsequent evaluations, including MTT assay, antibacterial activity testing, and biofilm formation analysis, were conducted to assess the efficiency of the synthesized TMNC. Cytotoxicity and anti-human oral squamous cell carcinoma activities of TMNC were evaluated using the Human Oral Cancer cell line (KB) cell line through MTT assay, demonstrating a dose-dependent increase in anti-human oral squamous cell carcinoma activity against the KB cell line compared to the normal cell line, resulting in notably high cell viability. Furthermore, an ultrasonic probe was employed to incorporate TMNC onto dental suturing threads, with different concentrations of TMNC, ultrasonic power levels, and durations considered to determine optimal embedding conditions that result in the highest antibacterial activity. The inhibitory effects of TMNC, both in well diffusion assays and when incorporated into dental suturing threads, against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria on Mueller-Hinton agar (MHA) were assessed using various concentrations of TMNC. The results of the study indicated that the efficacy of TMNC in inhibiting bacterial growth on dental suturing threads remained impressive, even at low concentrations. Moreover, an evaluation of their potential to destabilize biofilms formed by S. aureus and E. coli, the two pathogens in humans, indicated that TMNC would be a promising anti-biofilm agent.

Development of Clindamycin-Releasing Polyvinyl Alcohol Hydrogel with Self-Healing Property for the Effective Treatment of Biofilm-Infected Wounds

Self-healing hydrogels have good mechanical strength, can endure greater external force, and have the ability to heal independently, resulting in a strong bond between the wound and the material. Bacterial biofilm infections are life-threatening. Clindamycin (Cly) can be produced in the form of a self-healing hydrogel preparation. It is noteworthy that the antibacterial self-healing hydrogels show great promise as a wound dressing for bacterial biofilm infection. In this study, we developed a polyvinyl alcohol/borax (PVA/B) self-healing hydrogel wound dressing that releases Cly. Four ratios of PVA, B, and Cly were used to make self-healing hydrogels: F1 (4%:0.8%:1%), F2 (4%:1.2%:1%), F3 (1.6%:1%), and F4 (4%:1.6%:0). The results showed that F4 had the best physicochemical properties, including a self-healing duration of 11.81 ± 0.34 min, swelling ratio of 85.99 ± 0.12%, pH value of 7.63 ± 0.32, and drug loading of 98.34 ± 11.47%. The B-O-C cross-linking between PVA and borax caused self-healing, according to FTIR spectra. The F4 formula had a more equal pore structure in the SEM image. The PVA/B-Cly self-healing hydrogel remained stable at 6 ± 2 °C for 28 days throughout the stability test. The Korsmeyer-Peppas model released Cly by Fickian diffusion. In biofilm-infected mouse wounds, PVA/B-Cly enhanced wound healing and re-epithelialization. Our results indicate that the PVA/B-Cly produced in this work has reliable physicochemical properties for biofilm-infected wound therapy.

Nanoparticle-Based Strategies for Managing Biofilm Infections in Wounds: A Comprehensive Review

Chronic wounds containing opportunistic bacterial pathogens are a growing problem, as they are the primary cause of morbidity and mortality in developing and developed nations. Bacteria can adhere to almost every surface, forming architecturally complex communities called biofilms that are tolerant to an individual's immune response and traditional treatments. Wound dressings are a primary source and potential treatment avenue for biofilm infections, and research has recently focused on using nanoparticles with antimicrobial activity for infection control. This Review categorizes nanoparticle-based approaches into four main types, each leveraging unique mechanisms against biofilms. Metallic nanoparticles, such as silver and copper, show promising data due to their ability to disrupt bacterial cell membranes and induce oxidative stress, although their effectiveness can vary based on particle size and composition. Phototherapy-based nanoparticles, utilizing either photodynamic or photothermal therapy, offer targeted microbial destruction by generating reactive oxygen species or localized heat, respectively. However, their efficacy depends on the presence of light and oxygen, potentially limiting their use in deeper or more shielded biofilms. Nanoparticles designed to disrupt extracellular polymeric substances directly target the biofilm structure, enhancing the penetration and efficacy of antimicrobial agents. Lastly, nanoparticles that induce biofilm dispersion represent a novel strategy, aiming to weaken the biofilm's defense and restore susceptibility to antimicrobials. While each method has its advantages, the selection of an appropriate nanoparticle-based treatment depends on the specific requirements of the wound environment and the type of biofilm involved. The integration of these nanoparticles into wound dressings not only promises enhanced treatment outcomes but also offers a reduction in the overall use of antibiotics, aligning with the urgent need for innovative solutions in the fight against antibiotic-tolerant infections. The overarching objective of employing these diverse nanoparticle strategies is to replace antibiotics or substantially reduce their required dosages, providing promising avenues for biofilm infection management.

Diabetes-related lower limb wounds: Antibiotic susceptibility pattern and biofilm formation

The expeditious incidence of diabetes mellitus in Riyadh, Saudi Arabia, there is a significant increase in the total number of people with diabetic foot ulcers. For diabetic lower limb wound infections (DLWs) to be effectively treated, information on the prevalence of bacteria that cause in this region as well as their patterns of antibiotic resistance is significant. Growing evidence indicates that biofilm formers are present in chronic DFU and that these biofilm formers promote the emergence of multi-drug antibiotic resistant (MDR) strains and therapeutic rejection. The current study targeted to isolate bacteria from wounds caused by diabetes specifically at hospitals in Riyadh and assess the bacterium's resistance to antibiotics and propensity to develop biofilms. Totally 63 pathogenic microbes were identified from 70 patients suffering from DFU. Sixteen (25.4%) of the 63 bacterial strains were gram-positive, and 47 (74.6%) were gram-negative. Most of the gram-negative bacteria were resistant to tigecycline, nitrofurantoin, ampicillin, amoxicillin, cefalotin, and cefoxitin. Several gram-negative bacteria are susceptible to piperacillin, meropenem, amikacin, gentamicin, imipenem, ciprofloxacin, and trimethoprim. The most significant antibiotic that demonstrated 100% susceptibility to all pathogens was meropenem. Serratia marcescens and Staphylococcus aureus were shown to have significant biofilm formers. MDR bacterial strains comprised about 87.5% of the biofilm former strains. To the best of our knowledge, Riyadh, Saudi Arabia is the first region where Serratia marcescens was the most common bacteria from DFU infections. Our research findings would deliver information on evidence-based alternative strategies to develop effective treatment approaches for DFU treatment.

Current Knowledge and Perspectives of Phage Therapy for Combating Refractory Wound Infections

Wound infection is one of the most important factors affecting wound healing, so its effective control is critical to promote the process of wound healing. However, with the increasing prevalence of multi-drug-resistant (MDR) bacterial strains, the prevention and treatment of wound infections are now more challenging, imposing heavy medical and financial burdens on patients. Furthermore, the diminishing effectiveness of conventional antimicrobials and the declining research on new antibiotics necessitate the urgent exploration of alternative treatments for wound infections. Recently, phage therapy has been revitalized as a promising strategy to address the challenges posed by bacterial infections in the era of antibiotic resistance. The use of phage therapy in treating infectious diseases has demonstrated positive results. This review provides an overview of the mechanisms, characteristics, and delivery methods of phage therapy for combating pathogenic bacteria. Then, we focus on the clinical application of various phage therapies in managing refractory wound infections, such as diabetic foot infections, as well as traumatic, surgical, and burn wound infections. Additionally, an analysis of the potential obstacles and challenges of phage therapy in clinical practice is presented, along with corresponding strategies for addressing these issues. This review serves to enhance our understanding of phage therapy and provides innovative avenues for addressing refractory infections in wound healing.

Cellular therapeutics and immunotherapies in wound healing - on the pulse of time?

Chronic, non-healing wounds represent a significant challenge for healthcare systems worldwide, often requiring significant human and financial resources. Chronic wounds arise from the complex interplay of underlying comorbidities, such as diabetes or vascular diseases, lifestyle factors, and genetic risk profiles which may predispose extremities to local ischemia. Injuries are further exacerbated by bacterial colonization and the formation of biofilms. Infection, consequently, perpetuates a chronic inflammatory microenvironment, preventing the progression and completion of normal wound healing. The current standard of care (SOC) for chronic wounds involves surgical debridement along with localized wound irrigation, which requires inpatient care under general anesthesia. This could be followed by, if necessary, defect coverage via a reconstructive ladder utilizing wound debridement along with skin graft, local, or free flap techniques once the wound conditions are stabilized and adequate blood supply is restored. To promote physiological wound healing, a variety of approaches have been subjected to translational research. Beyond conventional wound healing drugs and devices that currently supplement treatments, cellular and immunotherapies have emerged as promising therapeutics that can behave as tailored therapies with cell- or molecule-specific wound healing properties. However, in contrast to the clinical omnipresence of chronic wound healing disorders, there remains a shortage of studies condensing the current body of evidence on cellular therapies and immunotherapies for chronic wounds. This review provides a comprehensive exploration of current therapies, experimental approaches, and translational studies, offering insights into their efficacy and limitations. Ultimately, we hope this line of research may serve as an evidence-based foundation to guide further experimental and translational approaches and optimize patient care long-term.

Biofilm Formation and Antimicrobial Resistance of Staphylococcus aureus and Streptococcus uberis Isolates from Bovine Mastitis

This study aimed to assess (a) the biofilm producer ability and antimicrobial resistance profiles of Staphylococcus (Staph.) aureus and Streptococcus (Strep.) uberis isolated from cows with clinical mastitis (CM) and subclinical mastitis (SCM), and (b) the association between biofilm producer ability and antimicrobial resistance. We isolated a total of 197 Staph. aureus strains (SCM = 111, CM = 86) and 119 Strep. uberis strains (SCM = 15, CM = 104) from milk samples obtained from 316 cows distributed in 24 dairy herds. Biofilm-forming ability was assessed using the microplate method, while antimicrobial susceptibility was determined using the disk diffusion method against 13 antimicrobials. Among the isolates examined, 57.3% of Staph. aureus and 53.8% of Strep. uberis exhibited the ability to produce biofilm, which was categorized as strong, moderate, or weak. In terms of antimicrobial susceptibility, Staph. aureus isolates displayed resistance to penicillin (92.9%), ampicillin (50.8%), and tetracycline (52.7%). Conversely, Strep. uberis isolates exhibited resistance to penicillin (80.6%), oxacillin (80.6%), and tetracycline (37.8%). However, no significant correlation was found between antimicrobial resistance patterns and biofilm formation ability among the isolates.

Extracellular vesicles from Staphylococcus aureus promote the pathogenicity of Pseudomonas aeruginosa

Co-infections with Staphylococcus aureus and Pseudomonas aeruginosa are common in patients with chronic wounds, but little is known about their synergistic effect mediated by extracellular vesicles (EVs). In this study, we investigated the effect of EVs derived from S. aureus (SaEVs) on the pathogenicity of P. aeruginosa. By using lipophilic dye, we could confirm the fusion between SaEV and P. aeruginosa membranes. However, SaEVs did not alter the growth and antibiotic susceptible pattern of P. aeruginosa. Differential proteomic analysis between SaEV-treated and non-treated P. aeruginosa was performed, and the results revealed that lipopolysaccharide (LPS) biosynthesis protein in P. aeruginosa significantly increased after SaEV-treatment. Regarding this result, we also found that SaEVs promoted LPS production, biofilm formation, and expression of polysaccharide polymerization-related genes in P. aeruginosa. Furthermore, invasion of epithelial cells by SaEV-pretreated P. aeruginosa was enhanced. On the other hand, uptake of P. aeruginosa by RAW 264.7 macrophages was impaired after pretreatment P. aeruginosa with SaEVs. Proteomic analysis SaEVs revealed that SaEVs contain the proteins involving in host cell colonization, inhibition of host immune response, anti-phagocytosis of the macrophages, and protein translocation and iron uptake of S. aureus. In conclusion, SaEVs serve as a mediator that promote P. aeruginosa pathogenicity by enhancing LPS biosynthesis, biofilm formation, epithelial cell invasion, and macrophage uptake impairment.

Xanthone Derivatives Enhance the Therapeutic Potential of Neomycin against Polymicrobial Gram-Negative Bacterial Infections

Gram-negative bacterial infections are difficult to manage as many antibiotics are ineffective owing to the presence of impermeable bacterial membranes. Polymicrobial infections pose a serious threat due to the inadequate efficacy of available antibiotics, thereby necessitating the administration of antibiotics at higher doses. Antibiotic adjuvants have emerged as a boon as they can augment the therapeutic potential of available antibiotics. However, the toxicity profile of antibiotic adjuvants is a major hurdle in clinical translation. Here, we report the design, synthesis, and biological activities of xanthone-derived molecules as potential antibiotic adjuvants. Our SAR studies witnessed that the p-dimethylamino pyridine-derivative of xanthone (X8) enhances the efficacy of neomycin (NEO) against Escherichia coli and Pseudomonas aeruginosa and causes a synergistic antimicrobial effect without any toxicity against mammalian cells. Biochemical studies suggest that the combination of X8 and NEO, apart from inhibiting protein synthesis, enhances the membrane permeability by binding to lipopolysaccharide. Notably, the combination of X8 and NEO can disrupt the monomicrobial and polymicrobial biofilms and show promising therapeutic potential against a murine wound infection model. Collectively, our results unveil the combination of X8 and NEO as a suitable adjuvant therapy for the inhibition of the Gram-negative bacterial infections.

Bacterial Biofilm in Chronic Wounds and Possible Therapeutic Approaches

Wound repair and skin regeneration is a very complex orchestrated process that is generally composed of four phases: hemostasis, inflammation, proliferation, and remodeling. Each phase involves the activation of different cells and the production of various cytokines, chemokines, and other inflammatory mediators affecting the immune response. The microbial skin composition plays an important role in wound healing. Indeed, skin commensals are essential in the maintenance of the epidermal barrier function, regulation of the host immune response, and protection from invading pathogenic microorganisms. Chronic wounds are common and are considered a major public health problem due to their difficult-to-treat features and their frequent association with challenging chronic infections. These infections can be very tough to manage due to the ability of some bacteria to produce multicellular structures encapsulated into a matrix called biofilms. The bacterial species contained in the biofilm are often different, as is their capability to influence the healing of chronic wounds. Biofilms are, in fact, often tolerant and resistant to antibiotics and antiseptics, leading to the failure of treatment. For these reasons, biofilms impede appropriate treatment and, consequently, prolong the wound healing period. Hence, there is an urgent necessity to deepen the knowledge of the pathophysiology of delayed wound healing and to develop more effective therapeutic approaches able to restore tissue damage. This work covers the wound-healing process and the pathogenesis of chronic wounds infected by biofilm-forming pathogens. An overview of the strategies to counteract biofilm formation or to destroy existing biofilms is also provided.

An Overview of Biofilm-Associated Infections and the Role of Phytochemicals and Nanomaterials in Their Control and Prevention

Biofilm formation is considered one of the primary virulence mechanisms in Gram-positive and Gram-negative pathogenic species, particularly those responsible for chronic infections and promoting bacterial survival within the host. In recent years, there has been a growing interest in discovering new compounds capable of inhibiting biofilm formation. This is considered a promising antivirulence strategy that could potentially overcome antibiotic resistance issues. Effective antibiofilm agents should possess distinctive properties. They should be structurally unique, enable easy entry into cells, influence quorum sensing signaling, and synergize with other antibacterial agents. Many of these properties are found in both natural systems that are isolated from plants and in synthetic systems like nanoparticles and nanocomposites. In this review, we discuss the clinical nature of biofilm-associated infections and some of the mechanisms associated with their antibiotic tolerance. We focus on the advantages and efficacy of various natural and synthetic compounds as a new therapeutic approach to control bacterial biofilms and address multidrug resistance in bacteria.

Evaluating the cost-effectiveness of diabetic foot ulcer management by wound care specialists in Indonesia

Diabetic foot ulcers affect quality of life and economically burden patients and the Indonesian healthcare system. The comparative cost-effectiveness of wound care specialists in private practices (e.g., wound clinics) and wound care nurses in national hospitals remains unknown. Thus, we used a decision tree to compare the cost and healing rates for patients after 12 weeks of wound care. Uncertainty was addressed using one-way and probabilistic sensitivity analyses. Among 89 participants (42 in the national hospital and 47 in the private practice), no significant differences were observed between the two groups in terms of sex, age, education level, smoking status, duration of diabetes, Wagner wound classification, glycated haemoglobin levels, neuropathy status, ankle-brachial index, baseline characteristics, quality of life, DMIST (depth, maceration, inflammation/infection, size, tissue type of the wound bed, type of wound edge, and tunnelling/undermining) score and wound location (p > 0.05). However, significant differences were observed for days from first visit/assessment until complete healing, mean quality of life (p ≤ 0.001) and wound size (p = 0.047). Wound care specialists in private practices had a significantly lower cost of 2,804,423.3 Indonesian rupiah compared to 6,483,493.4 Indonesian rupiah for wound care nurses in national hospitals. The incremental cost-effectiveness ratio was -165,723.9. Therefore, wound care specialists in private practices are more cost-effective for managing diabetic foot ulcers. Probability sensitivity analysis confirmed that 80%-90% of the scenarios were cost-effective. These findings may inform healthcare resource allocation in Indonesia. Additionally, evidence-based cost-effectiveness measures were strengthened in private practices and national hospitals.

Hyperbaric oxygen therapy counteracts Pseudomonas aeruginosa biofilm micro-compartment phenomenon in murine thermal wounds

Background

Biofilm antibiotic tolerance is partly explained by the behavior of a biofilm as an independent pharmacokinetic micro-compartment. Hyperbaric oxygen therapy has been shown to potentiate antibiotic effects in biofilms. The present study investigates the effect of hyperbaric oxygen therapy (HBOT) on the biofilm micro-pharmacokinetic/pharmacodynamic behavior of tobramycin in an animal biofilm model.

Methods

Full-thickness necroses were created mid-scapular on mice by means of a thermal lesion. After four days, three 16 h seaweed alginate biofilm beads containing Pseudomonas aeruginosa PAO1 were inserted under the necrosis, and three beads were inserted under the adjacent non-affected skin. The mice were randomized to three groups I) HBOT for 1.5 h at 2.8 atm and 0.8 mg tobramycin/mouse subcutaneously; II) Tobramycin as monotherapy, same dose; III) Saline control group. Half the number of mice from group 1 and 2 were sacrificed, and beads were recovered in toto after 3 h and the other half and the placebo mice were sacrificed and beads collected after 4.5 h.

Results

Lower CFUs were seen in the burned group receiving HBOT at 3 and 4.5 h compared to beads in the atmospheric environment (p = 0.043 and p = 0.0089). At 3 h, no CFU difference was observed in the non-burned skin (HBOT vs atmospheric). At 4.5 h, CFU in the non-burned skin had lower CFUs in the group receiving HBOT compared to the corresponding atmospheric group (p = 0.02). CFU was higher in the burned skin than in the non-burned skin at 3 h when HBOT was applied (p = 0.04), effect faded out at 4.5 h.At both time points, the tobramycin content in the beads under burned skin were higher in the HBOT group than in the atmospheric groups (p = 0.031 and p = 0.0078). Only at 4.5 h a higher tobramycin content was seen in the beads under the HBOT-treated burned skin than the beads under the corresponding non-burned skin (p = 0.006).

Conclusion

HBOT, as an anti-biofilm adjuvant treatment of chronic wounds, counteracts biofilm pharmacokinetic micro-compartmentalization through increased available tobramycin and augmented bacterial killing.

α,α-disubstituted β-amino amides eliminate Staphylococcus aureus biofilms by membrane disruption and biomass removal

Bacterial biofilms account for up to 80% of all infections and complicate successful therapies due to their intrinsic tolerance to antibiotics. Biofilms also cause serious problems in the industrial sectors, for instance due to the deterioration of metals or microbial contamination of products. Efforts are put in finding novel strategies in both avoiding and fighting biofilms. Biofilm control is achieved by killing and/or removing biofilm or preventing transition to the biofilm lifestyle. Previous research reported on the anti-biofilm potency of α,α-disubstituted β-amino amides A1, A2 and A3, which are small antimicrobial peptidomimetics with a molecular weight below 500 Da. In the current study it was investigated if these derivatives cause a fast disintegration of biofilm bacteria and removal of Staphylococcus aureus biofilms. One hour incubation of biofilms with all three derivatives resulted in reduced metabolic activity and membrane permeabilization in S. aureus (ATCC 25923) biofilms. Bactericidal properties of these derivatives were attributed to a direct effect on membranes of biofilm bacteria. The green fluorescence protein expressing Staphylococcus aureus strain AH2547 was cultivated in a CDC biofilm reactor and utilized for disinfectant efficacy testing of A3, following the single tube method (American Society for Testing and Materials designation number E2871). A3 at a concentration of 90 μM acted as fast as 100 μM chlorhexidine and was equally effective. Confocal laser scanning microscopy studies showed that chlorhexidine treatment lead to fluorescence fading indicating membrane permeabilization but did not cause biomass removal. In contrast, A3 treatment caused a simultaneous biofilm fluorescence loss and biomass removal. These dual anti-biofilm properties make α,α-disubstituted β-amino amides promising scaffolds in finding new control strategies against recalcitrant biofilms.

Evaluation of the Microbial Profile on the Polydioxanone Membrane and the Collagen Membrane Exposed to Multi-Species Subgingival Biofilm: An In Vitro Study

Dehiscence in surgeries involving membranes often leads to bacterial contamination, hindering the healing process. This study assessed bacterial colonization on various membrane materials. Polydioxanone (PDO) membranes, with thicknesses of 0.5 mm and 1 mm, and a collagen membrane were examined. Packages containing polystyrene pins were crafted using these membranes, attached to 24-well plates, and exposed to oral bacteria from supra and subgingival biofilm. After a week's anaerobic incubation, biofilm formation was evaluated using the DNA-DNA hybridization test. Statistical analysis employed the Kruskal-Wallis test with Dunn's post hoc test. The biofilm on the polystyrene pins covered by the 0.5 mm PDO membrane showed a higher count of certain pathogens. The collagen membrane had a greater total biofilm count on its inner surface compared to both PDO membranes. The external collagen membrane face had a higher total biofilm count than the 0.5 mm PDO membrane. Furthermore, the 1 mm PDO membrane exhibited a greater count of specific pathogens than its 0.5 mm counterpart. In conclusion, the collagen membrane presented more biofilm and pathogens both internally and on its inner surface.

Unlocking the Power of Onion Peel Extracts: Antimicrobial and Anti-Inflammatory Effects Improve Wound Healing through Repressing Notch-1/NLRP3/Caspase-1 Signaling

Onion peels are often discarded, representing an unlimited amount of food by-products; however, they are a valuable source of bioactive phenolics. Thus, we utilized UPLC-MS/MS to analyze the metabolomic profiles of red (RO) and yellow (YO) onion peel extracts. The cytotoxic (SRB assay), anti-inflammatory (Griess assay), and antimicrobial (sensitivity test, MIC, antibiofilm, and SP-SDS tests) properties were assessed in vitro. Additionally, histological analysis, immunohistochemistry, and ELISA tests were conducted to investigate the healing potential in excisional skin wound injury and Candida albicans infection in vivo. RO extract demonstrated antibacterial activity, limited skin infection with C. albicans, and improved the skin's appearance due to the abundance of quercetin and anthocyanin derivatives. Both extracts reduced lipopolysaccharide-induced nitric oxide release in vitro and showed a negligible cytotoxic effect on MCF-7 and HT29 cells. When extracts were tested in vivo for their ability to promote tissue regeneration, it was found that YO peel extract had the greatest impact. Further biochemical analysis revealed that YO extract suppressed NLRP3/caspase-1 signaling and decreased inflammatory cytokines. Furthermore, YO extract decreased Notch-1 levels and boosted VEGF-mediated angiogenesis. Our findings imply that onion peel extract can effectively treat wounds by reducing microbial infection, reducing inflammation, and promoting tissue regeneration.