The humanistic and economic burden of chronic wounds: a protocol for a systematic review

Real-Life Data on Wound Healing Speed and Duration to Wound Closure by Different Aetiology in a Primary Care Centre in the Netherlands

Correct classification of wounds is of paramount importance for diagnostic and therapeutic pathways. The aim of this study was to provide insight in the incidence of different aetiology of wounds and the healing time in a primary care setting. All patients with a wound presented in Primary Care (PC) practice from January 2017 through 2020 were included. A retrospective analysis related to age, sex, duration of wound healing, healing-rates, aetiology and comorbidity of the patients was performed. The prevalence of wounds in primary care was is 3.9 per 1000. In more than 90% of the wounds heal within 37 days. The wound healing speed and duration to closure differ significantly (P = .002) between aetiology. This study shows that 90% of wounds that enter a Dutch GP practice heal within 37 days. This study provides unique data on wound healing rates differentiated by etiology.

The rat as an animal model in chronic wound research: An update

The increasing global prevalence of chronic wounds underscores the growing importance of developing effective animal models for their study. This review offers a critical evaluation of the strengths and limitations of rat models frequently employed in chronic wound research and proposes potential improvements. It explores these models in the context of key comorbidities, including diabetes, venous and arterial insufficiency, pressure-induced blood flow obstruction, and infections. Additionally, the review examines important wound factors including age, sex, smoking, and the impact of anesthetic and analgesic drugs, acknowledging their substantial effects on research outcomes. A thorough understanding of these variables is crucial for refining animal models and can provide valuable insights for future research endeavors.

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.

Magneto-responsive biocomposites in wound healing: from characteristics to functions

The number of patients with non-healing wounds continuously increases, and has become a prominent societal issue that imposes a heavy burden on both patients and the entire healthcare system. Although traditional dressings play an important role in wound healing, the complexity and diversity of the healing process pose serious challenges in this field. Magneto-responsive biocomposites, with their excellent biocompatibility, remote spatiotemporal controllability, and unique convenience, demonstrate enticing advantages in the field of wound dressings. However, current research on magneto-responsive biocomposites as wound dressings lacks comprehensive and in-depth reviews, which to some extent, restricts the deeper understanding and further development of this field. Based on this, this paper reviews the latest advances in magnetic responsive wound dressings for wound healing. First, we review the process of skin wound healing and parameters for assessing repair progress. Then, we systematically discuss the preparation strategies and unique characteristics of magneto-responsive biocomposites, focusing on magneto-induced orientation, magneto-induced mechanical stimulation, and magnetocaloric effect. Subsequently, this review elaborates the multiple mechanisms of magneto-responsive biocomposites in promoting wound healing, including regulating cell behavior, enhancing electrical signal, controlling drug release, and accelerating tissue reconstruction. Finally, we further propose the development direction and future challenges of magnetic responsive biomaterials as wound dressings in clinical application.

The Optimal Effective Dose of Adipose-Derived Stem Cell Exosomes in Wound Healing

INTRODUCTION

Although the effect of adipose-derived mesenchymal stem cell exosomes (ADSC-exos) on wound healing with different doses are shown in various studies, efficient and sufficient doses of ADSC-exos are still unknown. The study aimed to determine the optimal dose of ADSC-exos in wound healing.

METHODS

The 45 Sprague-Dawley rats were randomly divided into five groups, with seven animals in each. After dorsal circular defects were created, each wound was injected as follows: group 1: saline, group 2: 10 μg/mL of ADSC-exos, group 3: 100 μg/mL of ADSC-exos, group 4: 200 μg/mL of ADSC-exos, and group 5: 400 μg/mL of ADSC-exos. The effects of ADSC-exos on epithelization, angiogenesis, and collagen formation were analyzed macroscopically, histopathologically, and immunohistochemically on day 14.

RESULTS

A total of 200 μg/mL and 400 μg/mL ADSC-exos groups had higher epithelial tongue length, epithelial tongue area, and angiogenesis scores than the other groups. Although there was no statistical difference in fibrosis scores among groups, collagen fibers were becoming well-organized as the ADSC-exos doses increased. While the wound area was clinically smaller in the 200 μg/mL ADSC-exos group, there was no statistically significant difference among groups on day 14.

CONCLUSIONS

A total of 200 μg/mL of ADSC-exos was found to be the adequate and effective dose for re-epithelialization and angiogenesis in cutaneous wound healing. Moreover, the collagen density increased with a more regular pattern in the 200 μg/mL group, which can be important in scar regulation.

Monoclonal Antibodies in the Management of Inflammation in Wound Healing: An Updated Literature Review

Chronic wounds pose a significant clinical challenge due to their complex pathophysiology and the burden of long-term management. Monoclonal antibodies (mAbs) are emerging as a novel therapeutic option in managing difficult wounds, although comprehensive data on their use in wound care are lacking. This study aimed to explore existing scientific knowledge of mAbs in treating chronic wounds based on a rationale of direct inhibition of the main molecules involved in the underlying inflammatory pathophysiology. We performed a literature review excluding primary inflammatory conditions with potential ulcerative outcomes (e.g., hidradenitis suppurativa). mAbs were effective in treating wounds from 16 different etiologies. The most commonly treated conditions were pyoderma gangrenosum (treated with 12 different mAbs), lipoid necrobiosis, and cutaneous vasculitis (each treated with 3 different mAbs). Fourteen mAbs were analyzed in total. Rituximab was effective in 43.75% of cases (7/16 diseases), followed by tocilizumab (25%, 4/16 diseases), and both etanercept and adalimumab (18.75%, 3/16 conditions each). mAbs offer therapeutic potential for chronic wounds unresponsive to standard treatments. However, due to the complex molecular nature of wound healing, no single target molecule can be identified. Therefore, the use of mAbs should be considered as a translational approach for limited cases of multi-resistant conditions.

LincRNA-EPS Promotes Proliferation of Aged Dermal Fibroblast by Inducing CCND1

The aging process is linked to numerous cellular changes, among which are modifications in the functionality of dermal fibroblasts. These fibroblasts play a crucial role in sustaining the healing of skin wounds. Reduced cell proliferation is a hallmark feature of aged dermal fibroblasts. Long intergenic non-coding RNA (lincRNAs), such as LincRNA-EPS (Erythroid ProSurvival), has been implicated in various cellular processes. However, its role in aged dermal fibroblasts and its impact on the cell cycle and its regulator, Cyclin D1 (CCND1), remains unclear. Primary dermal fibroblasts were isolated from the skin of 17-week-old (young) and 88-week-old (aged) mice. Overexpression of LincRNA-EPS was achieved through plasmid transfection. Cell proliferation was detected using the MTT assay. Real-time PCR was used to quantify relative gene expressions. Our findings indicate a noteworthy decline in the expression of LincRNA-EPS in aged dermal fibroblasts, accompanied by reduced levels of CCND1 and diminished cell proliferation in these aging cells. Significantly, the overexpression of LincRNA-EPS in aged dermal fibroblasts resulted in an upregulation of CCND1 expression and a substantial increase in cell proliferation. Mechanistically, LincRNA-EPS induces CCND1 expression by sequestering miR-34a, which was dysregulated in aged dermal fibroblasts, and directly targeting CCND1. These outcomes underscore the crucial role of LincRNA-EPS in regulating CCND1 and promoting cell proliferation in aged dermal fibroblasts. Our study provides novel insights into the molecular mechanisms underlying age-related changes in dermal fibroblasts and their implications for skin wound healing. The significant reduction in LincRNA-EPS expression in aged dermal fibroblasts and its ability to induce CCND1 expression and enhance cell proliferation highlight its potential as a therapeutic target for addressing age-related skin wound healing.

Chia seed-mediated fabrication of ZnO/Ag/Ag2O nanocomposites: structural, antioxidant, anticancer, and wound healing studies

Plant extract-mediated fabrication of metal nanocomposites is used in cell proliferation inhibition and topical wound treatment, demonstrating significant effectiveness. Salvia hispanica L. (chia) seed extract (CE) is used as the reaction medium for the green fabrication of ecofriendly ZnO(CE) nanoparticles (NPs) and Ag/Ag2O(CE) and ZnO/Ag/Ag2O(CE) nanocomposites. The resultant nanoparticles and nanocomposite materials were characterized using UV-visible, Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy-dispersive X-ray (EDX) techniques. In the context of antioxidant studies, ZnO/Ag/Ag2O(CE) exhibited 57% reducing power and 86% 2,2, diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging. All three materials showed strong antibacterial activity against Staphylococcus aureus (S. aureus), Escherichia coli (E.coli), and Bacillus subtilis (B. subtilis) bacterial strains. Additionally, ZnO(CE), Ag/Ag2O(CE), and ZnO/Ag/Ag2O(CE) also revealed 64.47%, 42.56%, and 75.27% in vitro Michigan Cancer Foundation-7 (MCF7) cancer cell line inhibition, respectively, at a concentration of 100 μg/mL. Selectively, the most effective composite material, ZnO/Ag/Ag2O(CE), was used to evaluate in vivo wound healing potential in rat models. The study revealed 96% wound closure in 10 days, which was quite rapid healing compared to wound healing using clinically available ointment. Therefore, in conclusion, the ZnO/Ag/Ag2O(CE) nanocomposite material could be considered for further testing and formulation as a good anticancer and wound healing agent.

Porcine-derived collagen peptides promote re-epithelialisation through activation of integrin signalling

Chronic non-healing cutaneous wounds represent a major burden to patients and healthcare providers worldwide, emphasising the continued unmet need for credible and efficacious therapeutic approaches for wound healing. We have recently shown the potential for collagen peptides to promote proliferation and migration during cutaneous wound healing. In the present study, we demonstrate that the application of porcine-derived collagen peptides significantly increases keratinocyte and dermal fibroblast expression of integrin α2β1 and activation of an extracellular signal-related kinase (ERK)-focal adhesion kinase (FAK) signalling cascade during wound closure in vitro. SiRNA-mediated knockdown of integrin β1 impaired porcine-derived collagen peptide-induced wound closure and activation of ERK-FAK signalling in keratinocytes but did not impair ERK or FAK signalling in dermal fibroblasts, implying the activation of differing downstream signalling pathways. Studies in ex vivo human 3D skin equivalents subjected to punch biopsy-induced wounding confirmed the ability of porcine-derived collagen peptides to promote wound closure by enhancing re-epithelialisation. Collectively, these data highlight the translational and clinical potential for porcine-derived collagen peptides as a viable therapeutic approach to promote re-epithelialisation of superficial cutaneous wounds.

Negative pressure wound therapy in the management of postoperative spinal wound infections: a systematic review

INTRODUCTION

Postoperative wound infection after spinal surgery might be a challenge to manage. A wide range of procedures have been described for managing infected spinal wounds. An increasingly common procedure in the management of surgical site infections (SSI) is negative pressure wound therapy (NPWT), also known as vacuum-assisted closure. As there is a paucity of clear clinical advice the present investigation aims to update current evidence on the use of NPWT to manage postoperative SSI occurring after instrumented spine surgery.

METHODS

This systematic review was conducted according to the preferred reporting Items for systematic reviews and meta-analyses: the 2020 PRISMA statement. In January 2024, the following databases were accessed: PubMed, Web of Science, and Google Scholar. No time constraint was set for the search. All the clinical studies investigating the unique use of NPWT in treating postoperative spinal wound infections were accessed.

RESULTS

A total of 381 patients were included in the present study. Of them 52.5% (200 of 381 patients) were women. The mean age was 52.2 ± 15.2 years. The average length of the NPWT was 21.2 days (range 7-90 days).

CONCLUSION

NPWT could be a valuable adjuvant therapy for the management of SSI after spine surgery. Additional high-quality investigations are required to assess the efficacy and safety of NPWT in SSI after spine surgery, especially if combined with contraindications or risk factors, such as the presence of intraoperative CSF leak.

LEVEL OF EVIDENCE

Level IV, Systematic review.

Incorporation of natural and synthetic polymers into honey hydrogel for wound healing: A review

Background and Aims

The difficulty in treating chronic wounds due to the prolonged inflammation stage has affected a staggering 6.5 million people, accompanied by 25 billion USD annually in the United States alone. A 1.9% rise in chronic wound prevalence among Medicare beneficiaries was reported from 2014 to 2019. Besides, the global wound care market values were anticipated to increase from USD 20.18 billion in 2022 to USD 30.52 billion in 2030, suggesting an expected rise in chronic wounds financial burdens. The lack of feasibility in using traditional dry wound dressings sparks hydrogel development as an alternative approach to tackling chronic wounds. Since ancient times, honey has been used to treat wounds, including burns, and ongoing studies have also demonstrated its wound-healing capabilities on cellular and animal models. However, the fluidity and low mechanical strength in honey hydrogel necessitate the incorporation of other polymers. Therefore, this review aims to unravel the characteristics and feasibility of natural (chitosan and gelatin) and synthetic (polyvinyl alcohol and polyethylene glycol) polymers to be incorporated in the honey hydrogel.

Methods

Relevant articles were identified from databases (PubMed, Google Scholar, and Science Direct) using keywords related to honey, hydrogel, and polymers. Relevant data from selected studies were synthesized narratively and reported following a structured narrative format.

Results

The importance of honey's roles and mechanisms of action in wound dressings were discussed. Notable studies concerning honey hydrogels with diverse polymers were also included in this article to provide a better perspective on fabricating customized hydrogel wound dressings for various types of wounds in the future.

Conclusion

Honey's incapability to stand alone in hydrogel requires the incorporation of natural and synthetic polymers into the hydrogel. With this review, it is hoped that the fabrication and commercialization of the desired honey composite hydrogel for wound treatment could be brought forth.

Alcaligenes faecalis corrects aberrant matrix metalloproteinase expression to promote reepithelialization of diabetic wounds

Chronic wounds are a common and costly complication of diabetes, where multifactorial defects contribute to dysregulated skin repair, inflammation, tissue damage, and infection. We previously showed that aspects of the diabetic foot ulcer microbiota were correlated with poor healing outcomes, but many microbial species recovered remain uninvestigated with respect to wound healing. Here, we focused on Alcaligenes faecalis, a Gram-negative bacterium that is frequently recovered from chronic wounds but rarely causes infection. Treatment of diabetic wounds with A. faecalis accelerated healing during early stages. We investigated the underlying mechanisms and found that A. faecalis treatment promotes reepithelialization of diabetic keratinocytes, a process that is necessary for healing but deficient in chronic wounds. Overexpression of matrix metalloproteinases in diabetes contributes to failed epithelialization, and we found that A. faecalis treatment balances this overexpression to allow proper healing. This work uncovers a mechanism of bacterial-driven wound repair and provides a foundation for the development of microbiota-based wound interventions.

Extracellular Vesicles Derived from Opuntia ficus-indica Fruit (OFI-EVs) Speed Up the Normal Wound Healing Processes by Modulating Cellular Responses

Plant-derived extracellular vesicles (EVs) have been recognized as important mediators of intercellular communication able to transfer active biomolecules across the plant and animal kingdoms. EVs have demonstrated an impressive array of biological activities, displaying preventive and therapeutic potential in mitigating various pathological processes. Indeed, the simplicity of delivering exogenous and endogenous bioactive molecules to mammalian cells with their low cytotoxicity makes EVs suitable agents for new therapeutic strategies for a variety of pathologies. In this study, EVs were isolated from Opuntia ficus-indica fruit (OFI-EVs) and characterized by particle size distribution, concentration, and bioactive molecule composition. OFI-EVs had no obvious toxicity and demonstrated a protective role in the inflammatory process and oxidative stress in vitro model of chronic skin wounds. The results demonstrated that pretreatment with OFI-EVs decreased the activity and gene expression of pro-inflammatory cytokines (IL-6, IL-8, and TNF-α) in the LPS-stimulated human leukemia monocytic cell line (THP-1). Furthermore, OFI-EVs promote the migration of human dermal fibroblasts (HDFs), speeding up the normal wound healing processes. This study sheds light, for the first time, on the role of OFI-EVs in modulating important biological processes such as inflammation and oxidation, thereby identifying EVs as potential candidates for healing chronic cutaneous wounds.

miR-146a Decreases Inflammation and ROS Production in Aged Dermal Fibroblasts

Aging is associated with a decline in the functionality of various cell types, including dermal fibroblasts, which play a crucial role in maintaining skin homeostasis and wound healing. Chronic inflammation and increased reactive oxygen species (ROS) production are hallmark features of aging, contributing to impaired wound healing. MicroRNA-146a (miR-146a) has been implicated as a critical regulator of inflammation and oxidative stress in different cell types, yet its role in aged dermal fibroblasts and its potential relevance to wound healing remains poorly understood. We hypothesize that miR-146a is differentially expressed in aged dermal fibroblasts and that overexpression of miR-146a will decrease aging-induced inflammatory responses and ROS production. Primary dermal fibroblasts were isolated from the skin of 17-week-old (young) and 88-week-old (aged) mice. Overexpression of miR-146a was achieved through miR-146a mimic transfection. ROS were detected using a reliable fluorogenic marker, 2,7-dichlorofluorescin diacetate. Real-time PCR was used to quantify relative gene expression. Our investigation revealed a significant reduction in miR-146a expression in aged dermal fibroblasts compared to their younger counterparts. Moreover, aged dermal fibroblasts exhibited heightened levels of inflammatory responses and increased ROS production. Importantly, the overexpression of miR-146a through miR-146a mimic transfection led to a substantial reduction in inflammatory responses through modulation of the NF-kB pathway in aged dermal fibroblasts. Additionally, the overexpression of miR-146a led to a substantial decrease in ROS production, achieved through the downregulation of NOX4 expression in aged dermal fibroblasts. These findings underscore the pivotal role of miR-146a in mitigating both inflammatory responses and ROS production in aged dermal fibroblasts, highlighting its potential as a therapeutic target for addressing age-related skin wound healing.

Hydration response technology dressings for low to excessively exuding wounds: a systematic review

OBJECTIVE

The aim of this systematic review was to identify and qualify the current available evidence of the wound exudate handling capabilities and the cost-effectiveness of hydration response technology (HRT). HRT combines physically modified cellulose fibres and gelling agents resulting in wound dressings that absorb and retain larger quantities of wound exudate.

METHOD

A systematic search was conducted in MEDLINE (via PubMed and PubMed Central) according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The search was conducted using an unlimited search period. Studies or reviews that evaluated effect on wound exudate and cost-effectiveness, as well as the impact on wound healing were considered. Records focusing on wound management using HRT devices were included.

RESULTS

The literature search identified four studies and one comparative analysis, ranging from low to moderate quality, that compared HRT dressings to other interventions (carboxymethyl cellulose dressing, other superabsorbent dressings, negative pressure wound therapy).

CONCLUSION

The analysed data supported the beneficial use of dressings with HRT for exuding wounds which was characterised by fewer dressing changes, improved periwound skin conditions and reduced costs.

Challenges and Prospects of Development of Herbal Biomaterial Based Ethical Wound Care Products-A Scoping Review

Total wound care is an unmet therapeutic need considering the morbidity and mortality associated with the rising prevalence of nonhealing/chronic wounds. Current wound management fails to address all aspects/types of wounds despite the availability of scores of traditional and modern, investigational products. Traditional medicine drugs of wound healing repute validated to target multiple biological pathways and key events in the mammalian wound healing cascade, reportedly affecting wound healing phases. Advances in the development of biocomposite matrices and their analytical characterization warrant a relook at consolidating time-tested wound healing properties of herbal bioactives for prospective development as ethical wound care products. Aside from the bottlenecks of their multiconstituent profiling and clinical trial data generation, regulatory hurdles also cloister any systematic attempts at their re-engineering into clinical deliverables. In the context of national policy changes to bring in totally indigenous solutions, countries with a huge knowledge/material resource on wound healing bioactives need to essentially facilitate the same.

VOLKSMED Database: A Source for Forgotten Wound Healing Plants in Austrian Folk Medicine

The global increase in the incidence of wounds is concerning and fuels the search for new treatment options. The use of traditional medicinal plants in wound healing represents an appreciated available therapeutic possibility. This work introduces the VOLKSMED database, which contains plants and other materials used in Austrian folk medicine, either as monographs or mixtures. This work focuses on the monographs of the database. Concerning wound healing, Hypericum sp., Arnica montana, Calendula officinalis, Plantago sp., and Malva sp. are the most commonly used plants. The focus of this paper is set on selected lesser-known plants (Abies alba, Anthyllis vulneraria, Brassica sp., Gentiana sp., Larix decidua, Picea abies, Sambucus sp., Sanicula europaea) and their status quo in literature concerning wound healing. A systematic search using the databases SciFinder, SCOPUS, and PubMed yielded substantial evidence for the wound healing potential of Brassica sp., Gentiana sp., the Pinaceae A. abies, L. decidua, and P. abies, as well as Sambucus nigra. In vivo and clinical studies substantiate their use in Austrian folk medicine. According to the literature, especially A. vulneraria, Sambucus racemosa, and S. europaea would be worth investigating in-depth since data concerning their wound healing effects - even though scarce - are convincing. In conclusion, the VOLKSMED database contains promising opportunities for further treatment options in the field of wound healing. Future research should consider the listed plants to support their traditional use in Austrian folk medicine and possibly promote the implementation of old knowledge in modern medicine.

The application of small intestinal submucosa in tissue regeneration

The distinctive three-dimensional architecture, biological functionality, minimal immunogenicity, and inherent biodegradability of small intestinal submucosa extracellular matrix materials have attracted considerable interest and found wide-ranging applications in the domain of tissue regeneration engineering. This article presents a comprehensive examination of the structure and role of small intestinal submucosa, delving into diverse preparation techniques and classifications. Additionally, it proposes approaches for evaluating and modifying SIS scaffolds. Moreover, the advancements of SIS in the regeneration of skin, bone, heart valves, blood vessels, bladder, uterus, and urethra are thoroughly explored, accompanied by their respective future prospects. Consequently, this review enhances our understanding of the applications of SIS in tissue and organ repair and keeps researchers up-to-date with the latest research advancements in this area.

The past, present and future of polymicrobial infection research: Modelling, eavesdropping, terraforming and other stories

Over the last two centuries, great advances have been made in microbiology as a discipline. Much of this progress has come about as a consequence of studying the growth and physiology of individual microbial species in well-defined laboratory media; so-called "axenic growth". However, in the real world, microbes rarely live in such "splendid isolation" (to paraphrase Foster) and more often-than-not, share the niche with a plethora of co-habitants. The resulting interactions between species (and even between kingdoms) are only very poorly understood, both on a theoretical and experimental level. Nevertheless, the last few years have seen significant progress, and in this review, we assess the importance of polymicrobial infections, and show how improved experimental traction is advancing our understanding of these. A particular focus is on developments that are allowing us to capture the key features of polymicrobial infection scenarios, especially as those associated with the human airways (both healthy and diseased).

Defining wound bed conformability: a new testing methodology to assess the relative swelling rise of foam dressings

OBJECTIVE

Using a dressing that expands and conforms to the wound bed upon exudate absorption is one of the best ways to promote wound healing. While many products claim wound bed conformability, no externally replicated or verified test methodology had been developed to quantify a wound dressing's ability to conform to the wound bed. The Relative Swelling Rise (RSR) test methodology was developed to measure the relative swelling rise of foam dressings upon fluid absorption, and offers a quantifiable and easily replicated method to measure wound bed conformability.

METHOD

The RSR test method was developed, validated and reliability tested by Coloplast A/S, Denmark. External replication was provided by ALS Odense, Denmark (previously DB Lab). Circular fences provide a fixed diameter to apply and contain the fluid and prevent horizontal spreading in the test set-up. The swelling height is quantified relative to the fence's inner diameter, i.e., the ratio alpha (α), and allows evaluation of a material's ability to conform to the wound bed.

RESULTS

Biatain Silicone foam products (n=3, Coloplast A/S, Denmark) were tested, all afforded an average α-ratio from 0.30 to 0.60. The relative standard deviations were between 1-3%, demonstrating the strength of the test. Robustness of the methodology was demonstrated through the internal validation study, the reliability study, and both an internal and external replication study, as well as a systematic literature review and expert review of the construct, content, criterion and generalisability of the method.

CONCLUSION

Having a validated, effective and easily replicable testing method to quantify wound bed conformability of foam dressings is an important step towards achieving better healing outcomes.

Is Shock Wave Application Effective on Various Chronic Wounds in the Geriatric Population? Preliminary Clinical Study

Purpose

Extracorporeal shock wave therapy (ESWT) is a beneficial adjunct modality for chronic wounds. Limited research has been conducted on pressure ulcers (PUs), while the majority of studies have focused on diabetic foot ulcers (DFUs) and venous leg ulcers (VLUs). This study aimed to evaluate the short-term effects of radial ESWT in older adults with chronic wounds.

Patients and Methods

This study involved a total of 31 wounds: PUs (n=22), VLUs (n=7), and DFUs (n=2). A single radial ESWT was performed with 300 + 100 shocks per cm2, pressure of 2.5 bar, energy of 0.15 mJ/mm2, and frequency of 5 Hz. Assessments using digital planimetry and clinical methods, utilizing the Wound Bed Score (WBS) and the Bates-Jansen Wound Assessment Tool (BWAT) were performed before the radial ESWT application (M0) and one week after (M1).

Results

A significant wound decrease in planimetry was noted (pre-ESWT vs post-ESWT), with wound area from 9.4 cm2 to 6.2 cm2, length from 6.4 cm to 3.9 cm, and width from 2.8 cm to 2.1 cm (p<0.001). Additionally, a substantial clinical improvement was noted in both the WBS with a 31.25% increase and the BWAT with a 20.00% increase (p<0.001). It was also found a significant correlation between the planimetric and clinical outcomes for both tools: WBS (r=-0.446, p=0.012) and BWAT (r=0.327, p=0.073).

Conclusion

The ESWT application yields substantial immediate clinical effects that support the healing of chronic wounds in older adults. Even a single ESWT session can prove to be clinically effective and beneficial in the management of chronic wounds.

The mutual regulation between γδ T cells and macrophages during wound healing

Macrophages are the main cells shaping the local microenvironment during wound healing. As the prime T cells in the skin, γδ T cells participate in regulating microenvironment construction, determining their mutual regulation helps to understand the mechanisms of wound healing, and explore innovative therapeutic options for wound repair. This review introduced their respective role in wound healing firstly, and then summarized the regulatory effect of γδ T cells on macrophages, including chemotaxis, polarization, apoptosis, and pyroptosis. Last, the retrograde regulation on γδ T cells by macrophages was also discussed. The main purpose is to excavate novel interventions for treating wound and provide new thought for further research.

Burden of Chronic Nonhealing Wounds: An Overview of the Worldwide Humanistic and Economic Burden to the Healthcare System

Chronic wounds have long been a significant public health concern, but the true impact of these wounds is unknown since research designs and measuring techniques vary, leading to inconsistent estimates. The definition of a wound is a loss of epithelial continuity caused by damage to the tissue. The following conditions can cause chronic wounds: panniculitis, pyoderma gangrenosum, traumatic, neurological, metabolic, hematologic, neoplastic, or infection-related. The growing global incidence of diabetes and the aging population necessitate greater attention to chronic wounds. Regrettably, it is sad that significant healthcare institutions have overlooked wound research. The study of health-related illnesses and occurrences in particular populations, including their distribution, frequency, and determinants, and the application of this research to control health problems.

Unlocking the Power of Light on the Skin: A Comprehensive Review on Photobiomodulation

Photobiomodulation (PBM) is a procedure that uses light to modulate cellular functions and biological processes. Over the past decades, PBM has gained considerable attention for its potential in various medical applications due to its non-invasive nature and minimal side effects. We conducted a narrative review including articles about photobiomodulation, LED light therapy or low-level laser therapy and their applications on dermatology published over the last 6 years, encompassing research studies, clinical trials, and technological developments. This review highlights the mechanisms of action underlying PBM, including the interaction with cellular chromophores and the activation of intracellular signaling pathways. The evidence from clinical trials and experimental studies to evaluate the efficacy of PBM in clinical practice is summarized with a special emphasis on dermatology. Furthermore, advancements in PBM technology, such as novel light sources and treatment protocols, are discussed in the context of optimizing therapeutic outcomes and improving patient care. This narrative review underscores the promising role of PBM as a non-invasive therapeutic approach with broad clinical applicability. Despite the need for further research to develop standard protocols, PBM holds great potential for addressing a wide range of medical conditions and enhancing patient outcomes in modern healthcare practice.

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.

Bringing innovative wound care polymer materials to the market: Challenges, developments, and new trends

The development of innovative products for treating acute and chronic wounds has become a significant topic in healthcare, resulting in numerous products and innovations over time. The growing number of patients with comorbidities and chronic diseases, which may significantly alter, delay, or inhibit normal wound healing, has introduced considerable new challenges into the wound management scenario. Researchers in academia have quickly identified promising solutions, and many advanced wound healing materials have recently been designed; however, their successful translation to the market remains highly complex and unlikely without the contribution of industry experts. This review article condenses the main aspects of wound healing applications that will serve as a practical guide for researchers working in academia and industry devoted to designing, evaluating, validating, and translating polymer wound care materials to the market. The article highlights the current challenges in wound management, describes the state-of-the-art products already on the market and trending polymer materials, describes the regulation pathways for approval, discusses current wound healing models, and offers a perspective on new technologies that could soon reach consumers. We envision that this comprehensive review will significantly contribute to highlighting the importance of networking and exchanges between academia and healthcare companies. Only through the joint of these two actors, where innovation, manufacturing, regulatory insights, and financial resources act in harmony, can wound care products be developed efficiently to reach patients quickly and affordably.

Telodendrimer functionalized hydrogel platform for sustained antibiotics release in infection control

Wound infection commonly causes delayed healing, especially in the setting of chronic wounds. Local release of antibiotics is considered a viable approach to treat chronic wounds. We have developed a versatile telodendrimer (TD) platform for efficient loading of charged antibiotic molecules via a combination of multivalent and synergistic charge and hydrophobic interactions. The conjugation of TD in biocompatible hydrogel allows for topical application to provide sustained antibiotic release. Notably, a drug loading capacity as high as 20 % of the drug-to-resin dry weight ratio can be achieved. The payload content (PC) and release profile of the various antibiotics can be optimized by fine-tuning TD density and valency in hydrogel based on the charge and hydrophobic features of the drug, e.g., polymyxin B (PMB), gentamycin (GM), and daptomycin (Dap), for effective infection control. We have shown that hydrogel with moderately reduced TD density demonstrates a more favorable release profile than hydrogel with higher TD density. Antibiotics loaded in TD hydrogel have comparable antimicrobial potency and reduced cytotoxicity compared to the free antibiotics due to a prolonged, controlled drug release profile. In a mouse model of skin and soft tissue infection, the subcutaneous administration of PMB-loaded TD hydrogel effectively eliminated the bacterial burden. Overall, these results suggest that engineerable TD hydrogels have great potential as a topical treatment to control infection for wound healing. STATEMENT OF SIGNIFICANCE: Wound infection causes a significant delay in the wound healing process, which results in a significant financial and resource burden to the healthcare system. PEGA-telodendrimer (TD) resin hydrogel is an innovative and versatile platform that can be fine-tuned to efficiently encapsulate different antibiotics by altering charged and hydrophobic structural moieties. Additionally, this platform is advantageous as the TD density in the resin can also be fine-tuned to provide the desired antibiotic payload release profile. Sustained antibiotics release through optimization of TD density provides a prolonged therapeutic window and reduces burst release-induced cytotoxicity compared to conventional antibiotics application. Studies in a preclinical mouse model of bacteria-induced skin and soft tissue infection demonstrated promising therapeutic efficacy as evidenced by effective infection control and prolonged antibacterial efficacy of antibiotics-loaded PEGA-TD resin. In conclusion, the PEGA-TD resin platform provides a highly customizable approach for effective antibiotics release with significant potential for topical application to treat various bacterial wound infections to promote wound healing.

Polyvinyl alcohol/carboxymethyl chitosan-based hydrogels loaded with taxifolin liposomes promote diabetic wound healing by inhibiting inflammation and regulating autophagy

With the improvement of modern living standards, the challenge of diabetic wound healing has significantly impacted the public health system. In this study, our objective was to enhance the bioactivity of taxifolin (TAX) by encapsulating it in liposomes using a thin film dispersion method. Additionally, polyvinyl alcohol/carboxymethyl chitosan-based hydrogels were prepared through repeated freeze-thawing. In vitro and in vivo experiments were conducted to investigate the properties of the hydrogel and its effectiveness in promoting wound healing in diabetic mice. The results of the experiments revealed that the encapsulation efficiency of taxifolin liposomes (TL) was 89.80 ± 4.10 %, with a drug loading capacity of 17.58 ± 2.04 %. Scanning electron microscopy analysis demonstrated that the prepared hydrogels possessed a porous structure, facilitating gas exchange and the absorption of wound exudates. Furthermore, the wound repair experiments in diabetic mice showed that the TL-loaded hydrogels (TL-Gels) could expedite wound healing by suppressing the inflammatory response and promoting the expression of autophagy-related proteins. Overall, this study highlights that TL-Gels effectively reduce wound healing time by modulating the inflammatory response and autophagy-related protein expression, thus offering promising prospects for the treatment of hard-to-heal wounds induced by diabetes.

Molecular characterization of chronic cutaneous wounds reveals subregion- and wound type-specific differential gene expression

A limited understanding of the pathology underlying chronic wounds has hindered the development of effective diagnostic markers and pharmaceutical interventions. This study aimed to elucidate the molecular composition of various common chronic ulcer types to facilitate drug discovery strategies. We conducted a comprehensive analysis of leg ulcers (LUs), encompassing venous and arterial ulcers, foot ulcers (FUs), pressure ulcers (PUs), and compared them with surgical wound healing complications (WHCs). To explore the pathophysiological mechanisms and identify similarities or differences within wounds, we dissected wounds into distinct subregions, including the wound bed, border, and peri-wound areas, and compared them against intact skin. By correlating histopathology, RNA sequencing (RNA-Seq), and immunohistochemistry (IHC), we identified unique genes, pathways, and cell type abundance patterns in each wound type and subregion. These correlations aim to aid clinicians in selecting targeted treatment options and informing the design of future preclinical and clinical studies in wound healing. Notably, specific genes, such as PITX1 and UPP1, exhibited exclusive upregulation in LUs and FUs, potentially offering significant benefits to specialists in limb preservation and clinical treatment decisions. In contrast, comparisons between different wound subregions, regardless of wound type, revealed distinct expression profiles. The pleiotropic chemokine-like ligand GPR15L (C10orf99) and transmembrane serine proteases TMPRSS11A/D were significantly upregulated in wound border subregions. Interestingly, WHCs exhibited a nearly identical transcriptome to PUs, indicating clinical relevance. Histological examination revealed blood vessel occlusions with impaired angiogenesis in chronic wounds, alongside elevated expression of genes and immunoreactive markers related to blood vessel and lymphatic epithelial cells in wound bed subregions. Additionally, inflammatory and epithelial markers indicated heightened inflammatory responses in wound bed and border subregions and reduced wound bed epithelialization. In summary, chronic wounds from diverse anatomical sites share common aspects of wound pathophysiology but also exhibit distinct molecular differences. These unique molecular characteristics present promising opportunities for drug discovery and treatment, particularly for patients suffering from chronic wounds. The identified diagnostic markers hold the potential to enhance preclinical and clinical trials in the field of wound healing.

Novel sampling technique maintaining the two-dimensional organization of microbes during cultivation from chronic wounds: The Imprint method

This study aimed to develop and validate "the Imprint method,", a technique for sampling microbes from chronic wounds while preserving their two-dimensional spatial organization. We used nylon filters to sample bacteria and compared with sampling using Eswabs in 12 patients. The Imprint method identified a mean of 0.93 unique species more than Eswab (4.3 ± 2.2 and 3.4 ± 1.4 unique species, respectively; mean ± SD; n = 30). Accuracy between the Eswab and the Imprint method was 93.2% and in cases of disagreement between methods, Imprint had a higher sensitivity in 6/8 of the most prevalent species. In vitro validation confirmed that the Imprint method could transfer bacterial colonies while replicating their two-dimensional organization and the area covered by bacteria on the plate sampled. Clinical testing demonstrated that the imprint method is a rapid and feasible technique that identified more unique bacterial species than Eswab with a good agreement between methods but that Imprint was better at detecting important pathogens such as Staphylococcus aureus and Pseudomonas aeruginosa. The Imprint method is a novel technique that cultures and records the two-dimensional organization of microbes, providing an alternative or supplement to conventional surface culture using Eswab.

Signaling Pathways Triggering Therapeutic Hydrogels in Promoting Chronic Wound Healing

In recent years, there has been a significant increase in the prevalence of chronic wounds, such as pressure ulcers, diabetic foot ulcers, and venous ulcers of the lower extremities. The main contributors to chronic wound formation are bacterial infection, prolonged inflammation, and peripheral vascular disease. However, effectively treating these chronic wounds remains a global challenge. Hydrogels have extensively explored as wound healing dressing because of their excellent biocompatibility and structural similarity to extracellular matrix (ECM). Nonetheless, much is still unknown how the hydrogels promote wound repair and regeneration. Signaling pathways play critical roles in wound healing process by controlling and coordinating cells and biomolecules. Hydrogels, along with their therapeutic ingredients that impact signaling pathways, have the potential to significantly enhance the wound healing process and its ultimate outcomes. Understanding this interaction will undoubtedly provide new insights into developing advanced hydrogels for wound repair and regeneration. This paper reviews the latest studies on classical signaling pathways and potential targets influenced by hydrogel scaffolds in chronic wound healing. This work hopes that it will offer a different perspective in developing more efficient hydrogels for treating chronic wounds.

Pyolytics as a product of the physical–chemical repurposing of antiseptics and an alternative to larval therapy for chronic wounds

The traditional treatment of chronic wounds involves daily cleansing of the wound surface from purulent necrotic masses using mechanical and medicinal methods, accompanied by regular replacement of wound dressing. In this case, medicinal wound cleansing lasts 10–15 mins from the time of replacement of the old wound dressing with the new one. According to established practice, medicinal sanitation of infected and purulent wounds during dressing involves irrigation of the wound surface with cleansing solutions, antiseptics, and/or antibiotics. In severe cases, the above therapy is supplemented with live larvae of the necrophage fly, which are injected into purulent necrotic masses and left in them under wound dressing until wounds are completely cleansed from pus. Nevertheless, the generally accepted course of treatment of chronic wounds remains ineffective. The use of pyolytics and their supplementation with wound dressings in the form of warm wet compresses, which create a local greenhouse effect in wounds, was reported to accelerate the healing of chronic wounds. Pyolytics are a group of antiseptics developed in Russia. They are warm alkaline solutions of hydrogen peroxide; when they interact with purulent necrotic masses, these solutions dissolve very quickly and foam them. Because of the interaction with pyolytics, thick purulent masses immediately turn into fluffy oxygenated foam. Pyolytics have been developed because of the physicochemical repurposing of aqueous solutions of sodium hydrogen carbonate and hydrogen peroxide. To accelerate the healing of chronic wounds, a recommendation was to irrigate the surface of chronic wounds with 3% hydrogen peroxide and 2–10% sodium bicarbonate solutions, heated to 37–45°C, which have alkaline activity at pH 8.4–8.5 and are enriched with dissolved carbon dioxide or oxygen (due to excess pressure of 0.2 atm). This study presented the importance of treating chronic wounds using politics and treatment outcomes using pyolytics along with warm moist dressing compresses, demonstrating a wound-healing effect. Consequently, physical and chemical reprofiling of antiseptics may make them effective pyolytics, and the combination of pyolytics with warm wound dressings such as warm moist compresses, which create a local greenhouse effect on wounds, accelerates the healing of chronic wounds.

Human Mesenchymal Stem Cells on Size-Sorted Gelatin Hydrogel Microparticles Show Enhanced In Vitro Wound Healing Activities

The demand for innovative therapeutic interventions to expedite wound healing, particularly in vulnerable populations such as aging and diabetic patients, has prompted the exploration of novel strategies. Mesenchymal stem cell (MSC)-based therapy emerges as a promising avenue for treating acute and chronic wounds. However, its clinical application faces persistent challenges, notably the low survivability and limited retention time of engraftment in wound environments. Addressing this, a strategy to sustain the viability and functionality of human MSCs (hMSCs) in a graft-able format has been identified as crucial for advanced wound care. Hydrogel microparticles (HMPs) emerge as promising entities in the field of wound healing, showcasing versatile capabilities in delivering both cells and bioactive molecules/drugs. In this study, gelatin HMPs (GelMPs) were synthesized via an optimized mild processing method. GelMPs with distinct diameter sizes were sorted and characterized. The growth of hMSCs on GelMPs with various sizes was evaluated. The release of wound healing promoting factors from hMSCs cultured on different GelMPs were assessed using scratch wound assays and gene expression analysis. GelMPs with a size smaller than 100 microns supported better cell growth and cell migration compared to larger sizes (100 microns or 200 microns). While encapsulation of hMSCs in hydrogels has been a common route for delivering viable hMSCs, we hypothesized that hMSCs cultured on GelMPs are more robust than those encapsulated in hydrogels. To test this hypothesis, hMSCs were cultured on GelMPs or in the cross-linked methacrylated gelatin hydrogel (GelMA). Comparative analysis of growth and wound healing effects revealed that hMSCs cultured on GelMPs exhibited higher viability and released more wound healing activities in vitro. This observation highlights the potential of GelMPs, especially those with a size smaller than 100 microns, as a promising carrier for delivering hMSCs in wound healing applications, providing valuable insights for the optimization of advanced therapeutic strategies.

Kick-Starting Wound Healing: A Review of Pro-Healing Drugs

Cutaneous wound healing consists of four stages: hemostasis, inflammation, proliferation/repair, and remodeling. While healthy wounds normally heal in four to six weeks, a variety of underlying medical conditions can impair the progression through the stages of wound healing, resulting in the development of chronic, non-healing wounds. Great progress has been made in developing wound dressings and improving surgical techniques, yet challenges remain in finding effective therapeutics that directly promote healing. This review examines the current understanding of the pro-healing effects of targeted pharmaceuticals, re-purposed drugs, natural products, and cell-based therapies on the various cell types present in normal and chronic wounds. Overall, despite several promising studies, there remains only one therapeutic approved by the United States Food and Drug Administration (FDA), Becaplermin, shown to significantly improve wound closure in the clinic. This highlights the need for new approaches aimed at understanding and targeting the underlying mechanisms impeding wound closure and moving the field from the management of chronic wounds towards resolving wounds.

Next-generation of smart dressings: Integrating multiplexed sensors and theranostic functions

Non-healing wounds represent a significant burden for healthcare systems and society, giving rise to severe economic and human issues. Currently, the use of dressings and visual assessment represent the primary and standard care for wounds. Conventional dressings, like cotton gauze, provide only passive physical protection. Besides, they end up paradoxically hampering the wound-healing process by producing tissue damage and pain when removed during routine check-ups. In response to these limitations, researchers, engineers, and technologists are developing innovative dressings that incorporate advanced diagnostic and therapeutic functionalities, coined as "smart dressings". Now, the maturation of smart dressing is bringing them closer to real-life applications, leading to an exciting new generation of these devices. The next generation of smart dressings is capable of monitoring in real-time multiple biomarkers while including pro-healing capabilities in a single platform. Such multiplexed and theranostic smart dressings are expected to offer a timely biomarker-directed diagnosis of non-healing wounds while enabling rapid, automated, and personalized treatments of infection and chronicity. Herein, we provide an insightful overview of these advantageous devices, delving into the diverse spectrum of possible engineering strategies. This encompasses the use of electrochemical and optical platforms with diverse multiplexing architectures, such as multi-zone sensing arrays and multi-layered devices. Open or closed-loop theranostic mechanisms using various stimuli-responsive materials that could be internally or externally controlled are also included. Finally, a critical discussion on the main challenges and future directions of smart dressings is also offered.

Nanophotonic and hydrogel-based diagnostic system for the monitoring of chronic wounds

Chronic wounds present a major healthcare burden, yet most wounds are only assessed superficially, and treatment is rarely based on the analysis of wound biomarkers. This lack of analysis is based on the fact that sampling of wound biomarkers is typically invasive, leading to a disruption of the wound bed while biomarker detection and quantification is performed in a remote laboratory, away from the point of care. Here, we introduce the diagnostic element of a novel theranostic system that can non-invasively sample biomarkers without disrupting the wound and that can perform biomarker quantification at the point of care, on a short timescale. The system is based on a thermally switchable hydrogel scaffold that enhances wound healing through regeneration of the wound tissue and allows the extraction of wound biomarkers non-destructively. We demonstrate the detection of two major biomarkers of wound health, i.e., IL-6 and TNF-α, in human matrix absorbed into the hydrogel dressing. Quantification of the biomarkers directly in the hydrogel is achieved using a chirped guided mode resonant biosensor and we demonstrate biomarker detection within the clinically relevant range of pg/mL to μg/mL concentrations. We also demonstrate the detection of IL-6 and TNF-α at concentration 1 ng/mL in hydrogel dressing absorbed with clinical wound exudate samples. The high sensitivity and the wide dynamic range we demonstrate are both essential for the clinical relevance of our system. Our test makes a major contribution towards the development of a wound theranostic for guided treatment and management of chronic wounds.

Self-Defensive Antimicrobial Shape Memory Polyurethanes with Honey-Based Compounds

Infection treatment plays a crucial role in aiding the body in wound healing. To that end, we developed a library of antimicrobial polymers based on segmented shape memory polyurethanes with nondrug-based antimicrobials (i.e., honey-based phenolic acids (PAs)) using both chemical and physical incorporation approaches. The antimicrobial shape memory polymers (SMPs) have high transition temperatures (>55 °C) to enable maintenance of temporary, programmed shapes in physiological conditions unless a specific external stimulus is present. Polymers showed tunable mechanical and shape memory properties by changing the ratio, chemistry, and incorporation method of PAs. Cytocompatible (∼100% cell viability) synthesized polymers inhibited growth rates of Staphylococcus aureus (∼100% with physically incorporated PAs and >80% with chemically incorporated PAs) and Escherichia coli (∼100% for samples with cinnamic acid (physical and chemical)). Crystal violet assays showed that all formulations inhibit biofilm formation in surrounding solutions, and chemically incorporated samples showed surface antibiofilm properties with S. aureus. Molecular dynamics simulations confirm that PAs have higher levels of interactions with S. aureus cell membranes than E. coli. Long-term antimicrobial properties were measured after storage of the sample in aqueous conditions; the polymers retained their antimicrobial properties against E. coli after up to 20 days. As a proof of concept, magnetic particles were incorporated into the polymer to trigger user-defined shape recovery by applying an external magnetic field. Shape recovery disrupted preformed S. aureus biofilms on polymer surfaces. This antimicrobial biomaterial platform could enable user- or environmentally controlled shape change and/or antimicrobial release to enhance infection treatment efforts.

Continuum of care in hard-to-heal wounds by copper dressings: a case series

OBJECTIVE

The quest for an ideal wound dressing has been a longstanding challenge due to the complex nature of wound healing, including stages of haemostasis, inflammation, maturation and remodelling, with overlapping timelines. This makes it difficult to find a single dressing that optimally supports all phases of wound healing. In addition, the ideal wound dressing should possess antibacterial properties and be capable of effectively debriding and lysing necrotic tissue. Copper is an essential trace element that participates in many of the key physiological wound healing processes.

METHOD

Copper stimulates secretion of various cytokines and growth factors, thus promoting angiogenesis, granulation tissue formation, extracellular matrix proteins secretion and re-epithelialisation. Harnessing this knowledge, we have used copper oxide-impregnated wound dressings in numerous cases and observed their benefits throughout the entire wound healing process.

RESULTS

This led us to postulate the 'continuum of care' hypothesis of copper dressings. In this study we describe four cases of hard-to-heal wounds of various aetiologies, in which we applied copper dressings consistently across all stages of wound healing, with rapid uneventful healing.

CONCLUSION

We believe we have successfully implemented the continuum of care principle.

Immobilization of Papain in Chitosan Membranes as a Potential Alternative for Skin Wounds

Papain (an enzyme from the latex of Carica papaya) is an interesting natural bioactive macromolecule used as therapeutic alternative for wound healing due to debridement action in devitalized or necrotic tissues. However, its use in high doses can induce potential skin irritation and side effects. In this study, experiments explored the ability of chitosan membrane to immobilize papain, consequently improving enzymatic activity and controlling enzyme release. Papain-loading capacity was tested via experiments of force microscopy (AFM), scanning electron microscopy (SEM-FEG), and X-ray diffraction analyses. Fourier transform infrared spectroscopy and thermal analyses assessed the enzyme interactions with the copolymer. The investigation of the feasibility of membranes included pH on the surface, elasticity, and breaking strength measurements. The surface wettability and swelling capacity of different formulations revealed the best formulation for in vitro papain release experiments. The membranes had a transparent, rough, crystalline characteristic, which was homogeneous with the membrane within the neutrality. The immobilization of papain in the chitosan membrane resulted in a decrease in the vibration band characteristic of pure papain, suggesting a displacement in the vibration bands in the FTIR spectrum. The presence of papain decreased hydrophobicity on the surface of the membrane and disturbed the membrane's ability to swell. Chitosan membranes containing papain 2.5% (0.04 g) and 5.0% (0.08 g) preserved feasible properties and improved the enzymatic activity compared (0.87 ± 0.12 AU/mg and 1.59 ± 0.10 AU/mg) with a free papain sample (0.0042 ± 0.001 AU/mg). Concentrations of over 10% (0.16 g) led to phase separation into membranes. Chitosan membranes exhibited a slow papain release behavior adjusted via the Higushi model. The experimental achievements suggest a novel and promising method for the enhancement of papain. The results indicate the potential for prolonged bioactivity for use on wounds.

Elaboration of Nanostructured Levan-Based Colloid System as a Biological Alternative with Antimicrobial Activity for Applications in the Management of Pathogenic Microorganisms

Considering the documented health benefits of bacterial exopolysaccharides (EPSs), specifically of bacterial levan (BL), including its intrinsic antimicrobial activity against certain pathogenic species, the current study concentrated on the development of active pharmaceutical ingredients (APIs) in the form of colloid systems (CoSs) containing silver nanoparticles (AgNPs) employing in-house biosynthesized BL as a reducing and capping agent. The established protocol of fermentation conditions implicating two species of lactic acid bacteria (LAB), i.e., Streptococcus salivarius K12 and Leuconostoc mesenteroides DSM 20343, ensured a yield of up to 25.7 and 13.7 g L-1 of BL within 72 h, respectively. An analytical approach accomplished by Fourier-transform infrared (FT-IR) spectroscopy allowed for the verification of structural features attributed to biosynthesized BL. Furthermore, scanning electron microscopy (SEM) revealed the crystalline morphology of biosynthesized BL with a smooth and glossy surface and highly porous structure. Molecular weight (Mw) estimated by multi-detector size-exclusion chromatography (SEC) indicated that BL biosynthesized using S. salivarius K12 has an impressively high Mw, corresponding to 15.435 × 104 kilodaltons (kDa). In turn, BL isolated from L. mesenteroides DSM 20343 was found to have an Mw of only 26.6 kDa. Polydispersity index estimation (PD = Mw/Mn) of produced BL displayed a monodispersed molecule isolated from S. salivarius K12, corresponding to 1.08, while this was 2.17 for L. mesenteroides DSM 20343 isolate. The presence of fructose as the main backbone and, to a lesser extent, glucose and galactose as side chain molecules in EPS hydrolysates was supported by HPLC-RID detection. In producing CoS-BL@AgNPs within green biosynthesis, the presence of nanostructured objects with a size distribution from 12.67 ± 5.56 nm to 46.97 ± 20.23 was confirmed by SEM and energy-dispersive X-ray spectroscopy (EDX). The prominent inhibitory potency of elaborated CoS-BL@AgNPs against both reference test cultures, i.e., Pseudomonas aeruginosa, Escherichia coli, Enterobacter aerogenes, and Staphylococcus aureus and those of clinical origin with multi-drug resistance (MDR), was confirmed by disc and well diffusion tests and supported by the values of the minimum inhibitory and bactericidal concentrations. CoS-BL@AgNPs can be treated as APIs suitable for designing new antimicrobial agents and modifying therapies in controlling MDR pathogens.

Digital Twin in Healthcare: A Study for Chronic Wound Management

Although the concept of digital twin technology has been in existence for nearly half a century, its application in healthcare is a relatively recent development. In healthcare, the utilization of digital twin and data-driven models has proven to enhance clinical decision support, particularly in the treatment and assessment of chronic wounds, leading to improved clinical outcomes. This article proposes the implementation of a digital twin in the domain of healthcare, specifically in the management of chronic wounds, by leveraging artificial intelligence techniques. The digital twin is composed of data collection, data processing, and AI models dedicated to wound healing. A novel AI pipeline is utilized to track the healing of chronic wounds. The digital twin, serving as a virtual representation of the actual wound, simulates and replicates the healing process. Furthermore, the proposed wound-healing prediction model effectively guides the treatment of chronic wounds. Additionally, by comparing the actual wound with its digital twin, the system enables early identification of non-healing wounds, facilitating timely adjustments and modifications to the treatment plan. By incorporating a digital twin in healthcare, the proposed system enables personalized and tailored treatments, potentially playing a crucial role in proactive problem identification.

PLGA-based electrospun nanofibers loaded with dual bioactive agent loaded scaffold as a potential wound dressing material

Chronic and infectious wounds are major public health issues with financial and clinical manifestations. Developing a multitasking extracellular matrix mimicking scaffold can bring revolution saving millions of lives. Many bioactive agents are offering therapeutic promises in managing infectious wounds but require a suitable delivery system to ensure not only their bioavailability possible on the wound site but also control their burst release hence making them either useless or highly cytotoxic. In this study, we reported the dual bioactive agent-loaded electrospinning nanofibers potentially useable against infectious wounds. The zinc oxide nanoparticles (ZnO NPs) and vascular endothelial growth factors (VEGF), highly relevant bioactive agents, were chosen to be co-delivered to the wound site through the core-shell electrospun membrane. The physicochemical properties of prepared membranes were characterized through various physicochemical tools. Our result demonstrated that PLGA polymer can be electrospun into smooth fibers. X-ray diffraction analysis revealed the successful loading of ZnO NPs which was further confirmed by TEM. The fabricated membrane exhibited a suitable mechanical behavior. Moreover, the incorporation of ZnO NPs has turned the nanofibers into an effective antibacterial scaffold. Besides, the membranes were also evaluated for their cytotoxicity. The in vitro cell culturing on various membranes revealed that cell maintained their maximum viability on all the membranes. The potential of in vivo wound healing was further demonstrated through animal experiments. Our results show that membranes could not only influence early wound contraction, but also better tissue organization demonstrated through histopathological evaluation. We successfully demonstrated the rich vascularization network by synching the actions of ZnO NPs and VEGF. In conclusion, the fabricated membranes possess suitable physicochemical properties and promising biological activity and hence should be further exploited for in vivo wound healing potential.

Topical application of Lactobacilli successfully eradicates Pseudomonas aeruginosa biofilms and promotes wound healing in chronic wounds

Chronic wounds are difficult to treat due to the presence of biofilm which prevents wound healing. Pseudomonas aeruginosa is one of the most common pathogens found in chronic wounds and conventional treatment strategies have been ineffective in the eradication of its biofilm, without harming the surrounding healthy tissue at the same time. Here, we introduced an innovative approach applying the probiotic product Bio-K+ (containing three lactobacilli) topically as an antimicrobial and antibiofilm agent. We identified lactic acid as the main active component. While antibiotics and antiseptics such as silver-ions only demonstrated limited efficacy, Bio-K+ was able to completely eradicate mature P. aeruginosa biofilms established in an in-vitro and ex-vivo human skin model. Furthermore, it demonstrated biocompatibility in the co-culture with human dermal fibroblasts and accelerated the migration of fibroblasts in a cell migration assay promoting wound healing. To enhance clinical practicability, we introduced Bio-K+ into the hydrocolloid dressing Aquacel, achieving sustained release of lactic acid and biofilm eradication. This new treatment approach applying probiotics could represent a major improvement in the management of chronic wounds and can be extended in treating other biofilm-associated infections.

Use of bioelectric dressings for patients with hard-to-heal wounds: a case report

There are many types of dressings available for the management of hard-to-heal (chronic) wounds. This case report illustrates the efficacy of bioelectric dressings in healing hard-to-heal wounds in five patients. Of the patients, four had diabetic foot ulcers (DFUs) and one had a surgical site infection. Wounds were examined using the TIMES concept and debridement was carried out if needed. Amorphous hydrogel was used as conduction fluid before the application of the bioelectric wound dressings. The wound was covered with foam dressing and crepe bandage. In this case report, among all five wounds, one wound healed completely while the other four reduced in size, with the presence of more granulation and re-epithelialisation. In this case report, bioelectric wound dressings were effective in managing infection and promoting wound healing.

Wirelessly Powered Drug-Free and Anti-Infective Smart Bandage for Chronic Wound Care

We present a wirelessly powered ultraviolet-C (UVC) radiation-based disinfecting bandage for sterilization and treatment in chronic wound care and management. The bandage contains embedded low-power UV light-emitting diodes (LEDs) in the 265 to 285 nm range with the light emission controlled via a microcontroller. An inductive coil is seamlessly concealed in the fabric bandage and coupled with a rectifier circuit to enable 6.78 MHz wireless power transfer (WPT). The maximum WPT efficiency of the coils is 83% in free space and 75% on the body at a coupling distance of 4.5 cm. Measurements show that the UVC LEDs are emitting radiant power of about 0.6 mW and 6.8 mW with and without fabric bandage, respectively, when wirelessly powered. The ability of the bandage to inactivate microorganisms was examined in a laboratory which shows that the system can effectively eradicate Gram-negative bacteria, Pseudoalteromonas sp. D41 strain, on surfaces in six hours. The proposed smart bandage system is low-cost, battery-free, flexible and can be easily mounted on the human body and, therefore, shows great promise for the treatment of persistent infections in chronic wound care.

Research hotspot and trend of chronic wounds: A bibliometric analysis from 2013 to 2022

Chronic wounds have been confirmed as a vital health problem facing people in the global population aging process. While significant progress has been achieved in the study of chronic wounds, the treatment effect should be further improved. The number of publications regarding chronic wounds has been rising rapidly. In this study, bibliometric analysis was conducted to explore the hotspots and trends in the research on chronic wounds. All relevant studies on chronic wounds between 2013 and 2022 were collected from the PubMed database of the Web of Science (WOS) and the National Center for Biotechnology Information (NCBI). The data were processed and visualised using a series of software. On that basis, more insights can be gained into hotspots and trends of this research field. Wound Repair and Regeneration has the highest academic achievement in the field of chronic wound research. The United States has been confirmed as the most productive country, and the University of California System ranks high among other institutions. Augustin, M. is the author of the most published study, and Frykberg, RG et al. published the most cited study. Furthermore, the hotspots of wound research over the last decade were identified (e.g., bandages, infection and biofilms, pathophysiology and therapy). This study will help researchers gain insights into chronic wound research's hotspots and trends accurately and quickly. Moreover, the exploration of bacterial biofilm and the pathophysiological mechanism of the chronic wound will lay a solid foundation and clear direction for treating chronic wounds.

Antibacterial Efficacy of Green Synthesized Silver Nanoparticles Using Salvia nubicola Extract against Ralstonia solanacearum, the Causal Agent of Vascular Wilt of Tomato

Ralstonia solanacearum is a phytopathogen causing bacterial wilt diseases of tomato and affecting its productivity, which leads to prominent economic losses annually. As an alternative to conventional pesticides, green synthesized nanoparticles are believed to possess strong antibacterial activities besides being cheap and ecofriendly. Here, we present the synthesis of silver nanoparticles (Sn-AgNPs) from medicinally important aqueous plant extracts of Salvia nubicola. Characterization of biologically synthesized nanoparticles was performed through UV-vis spectrophotometry, Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy (TEM), and thermogravimetric analysis. The antibacterial activity of the biosynthesized silver nanoparticles was tested against the phytopathogen R. solanacearum through in vitro experiments. Preliminary phytochemical analysis of the plant extracts revealed the presence of substantial amounts of flavonoids (57.08 mg GAE/g), phenolics (42.30 mg GAE/g), tannins, and terpenoids. The HPLC phenolic profile indicated the presence of 25 possible bioactive compounds. Results regarding green synthesized silver nanoparticles revealed the conformation of different functional groups through FTIR analysis, which could be responsible for the bioreduction and capping of Ag ions into silver NPs. TEM results revealed the spherical, crystalline shape of nanoparticles with the size in the range of 23-63 nm, which validates SEM results. Different concentrations of Sn-AgNPs (T1 (500 μg/mL) to T7 (78.1 μg/mL)) with a combination of plant extracts (PE-Sn-AgNPs) and plant extracts alone exhibited an efficient inhibition of R. solanacearum. These findings could be used as an effective alternative preparation against the bacterial wilt of tomato.

Multi-Functional Chitosan Nanovesicles Loaded with Bioactive Manganese for Potential Wound Healing Applications

Chronic skin wound is a chronic illness that possesses a risk of infection and sepsis. In particular, infections associated with antibiotic-resistant bacterial strains are challenging to treat. To combat this challenge, a suitable alternative that is complementary to antibiotics is desired for wound healing. In this work, we report multi-functional nanoscale chitosan vesicles loaded with manganese (Chi-Mn) that has potential to serve as a new tool to augment traditional antibiotic treatment for skin wound healing. Chi-Mn showed antioxidant activity increase over time as well as antimicrobial activity against E. coli and P. aeruginosa PA01. The modified motility assay that mimicked a skin wound before bacterial colonization showed inhibition of bacterial growth with Chi-Mn treatment at a low area density of 0.04 µg of Mn per cm2. Furthermore, this study demonstrated the compatibility of Chi-Mn with a commercial antibiotic showing no loss of antimicrobial potency. In vitro cytotoxicity of Chi-Mn was assessed with macrophages and dermal cell lines (J774A.1 and HDF) elucidating biocompatibility at a wide range (2 ppm-256 ppm). A scratch wound assay involving human dermal fibroblast (HDF) cells was performed to assess any negative effect of Chi-Mn on cell migration. Confocal microscopy study confirmed that Chi-Mn tested at the MIC (16 ppm Mn) has no effect on cell migration with respect to control. Overall, this study demonstrated the potential of Chi-Mn nanovesicles for wound healing applications.

Ozonated Sunflower Oil Exerted Potent Anti-Inflammatory Activities with Enhanced Wound Healing and Tissue Regeneration Abilities against Acute Toxicity of Carboxymethyllysine in Zebrafish with Improved Blood Lipid Profile

Ozonated sunflower oil (OSO) is an established therapeutic agent and nutraceutical harboring various therapeutic values, including antiallergic, derma-protective, and broad-spectrum antimicrobial activity. Conversely, the medicinal aspects of OSO for wound healing, tissue regeneration, and treatment of inflammation in dyslipidemia have yet to be fully elucidated. Herein, a comparative effect of OSO and sunflower oil (SO) was investigated to heal cutaneous wound and tissue regeneration of zebrafish impediment by carboxymethyllysine (CML) toxicity, following impact on hepatic inflammation and blood lipid profile. After OSO (final 2%, 1 μL) and SO's (final 2%, 1 μL) treatment, substantial healing was elicited by OSO in the cutaneous wound of zebrafish impaired by CML (final 25 μg). As an important event of wound healing, OSO scavenges the reactive oxygen species (ROS), rescues the wound from oxidative injury, and triggers the essential molecular events for the wound closer. Furthermore, the intraperitoneal injection of OSO was noted to counter the CML-induced adversity and prompt tissue regeneration in the amputated tail fin of zebrafish. Additionally, OSO counters the CML-induced neurotoxicity and rescues the zebrafish from acute mortality and paralysis, along with meticulous recovery of hepatic inflammation, fatty liver changes, and diminished ROS and proinflammatory interleukin (IL)-6 production. Moreover, OSO efficiently ameliorated CML-induced dyslipidemia by alleviating the total blood cholesterol (TC), triglyceride (TG), and increasing high-density lipoproteins cholesterol (HDL-C). The outcome of multivariate assessment employing principal component analysis and hierarchical cluster analysis supports a superior therapeutic potential of OSO over SO against the clinical manifestation of CML. Conclusively, OSO owing to its antioxidant and anti-inflammatory potential, counters CML-induced toxicity and promotes wound healing, tissue regeneration, hepatoprotection, improved blood lipid profile, and survivability of zebrafish.