Prevalence and incidence of chronic wounds and related complications: a protocol for a systematic review

Alginate-Based Materials Loaded with Nanoparticles in Wound Healing

Alginate is a naturally derived polysaccharide widely applied in drug delivery, as well as regenerative medicine, tissue engineering and wound care. Due to its excellent biocompatibility, low toxicity, and the ability to absorb a high amount of exudate, it is widely used in modern wound dressings. Numerous studies indicate that alginate applied in wound care can be enhanced with the incorporation of nanoparticles, revealing additional properties beneficial in the healing process. Among the most extensively explored materials, composite dressings with alginate loaded with antimicrobial inorganic nanoparticles can be mentioned. However, other types of nanoparticles with antibiotics, growth factors, and other active ingredients are also investigated. This review article focuses on the most recent findings regarding novel alginate-based materials loaded with nanoparticles and their applicability as wound dressings, with special attention paid to the materials of potential use in the treatment of chronic wounds.

New Smart Bioactive and Biomimetic Chitosan-Based Hydrogels for Wounds Care Management

Wound management represents a continuous challenge for health systems worldwide, considering the growing incidence of wound-related comorbidities, such as diabetes, high blood pressure, obesity, and autoimmune diseases. In this context, hydrogels are considered viable options since they mimic the skin structure and promote autolysis and growth factor synthesis. Unfortunately, hydrogels are associated with several drawbacks, such as low mechanical strength and the potential toxicity of byproducts released after crosslinking reactions. To overcome these aspects, in this study new smart chitosan (CS)-based hydrogels were developed, using oxidized chitosan (oxCS) and hyaluronic acid (oxHA) as nontoxic crosslinkers. Three active product ingredients (APIs) (fusidic acid, allantoin, and coenzyme Q10), with proven biological effects, were considered for inclusion in the 3D polymer matrix. Therefore, six API-CS-oxCS/oxHA hydrogels were obtained. The presence of dynamic imino bonds in the hydrogels' structure, which supports their self-healing and self-adapting properties, was confirmed by spectral methods. The hydrogels were characterized by SEM, swelling degree, pH, and the internal organization of the 3D matrix was studied by rheological behavior. Moreover, the cytotoxicity degree and the antimicrobial effects were also investigated. In conclusion, the developed API-CS-oxCS/oxHA hydrogels have real potential as smart materials in wound management, based on their self-healing and self-adapting properties, as well as on the benefits of APIs.

Antimicrobial Nano-Zinc Oxide Biocomposites for Wound Healing Applications: A Review

Chronic wounds are a major concern for global health, affecting millions of individuals worldwide. As their occurrence is correlated with age and age-related comorbidities, their incidence in the population is set to increase in the forthcoming years. This burden is further worsened by the rise of antimicrobial resistance (AMR), which causes wound infections that are increasingly hard to treat with current antibiotics. Antimicrobial bionanocomposites are an emerging class of materials that combine the biocompatibility and tissue-mimicking properties of biomacromolecules with the antimicrobial activity of metal or metal oxide nanoparticles. Among these nanostructured agents, zinc oxide (ZnO) is one of the most promising for its microbicidal effects and its anti-inflammatory properties, and as a source of essential zinc ions. This review analyses the most recent developments in the field of nano-ZnO–bionanocomposite (nZnO-BNC) materials—mainly in the form of films, but also hydrogel or electrospun bandages—from the different preparation techniques to their properties and antibacterial and wound-healing performances. The effect of nanostructured ZnO on the mechanical, water and gas barrier, swelling, optical, thermal, water affinity, and drug-release properties are examined and linked to the preparation methods. Antimicrobial assays over a wide range of bacterial strains are extensively surveyed, and wound-healing studies are finally considered to provide a comprehensive assessment framework. While early results are promising, a systematic and standardised testing procedure for the comparison of antibacterial properties is still lacking, partly because of a not-yet fully understood antimicrobial mechanism. This work, therefore, allowed, on one hand, the determination of the best strategies for the design, engineering, and application of n-ZnO-BNC, and, on the other hand, the identification of the current challenges and opportunities for future research.

Controlled Delivery of Vancomycin from Collagen-tethered Peptide Vehicles for the Treatment of Wound Infections

Despite the great promise of antibiotic therapy in wound infections, antibiotic resistance stemming from frequent dosing diminishes drug efficacy and contributes to recurrent infection. To identify improvements in antibiotic therapies, new antibiotic delivery systems that maximize pharmacological activity and minimize side effects are needed. In this study, we developed elastin-like peptide and collagen-like peptide nanovesicles (ECnVs) tethered to collagen-containing matrices to control vancomycin delivery and provide extended antibacterial effects against methicillin-resistant Staphylococcus aureus (MRSA). We observed that ECnVs showed enhanced entrapment efficacy of vancomycin by 3-fold as compared to liposome formulations. Additionally, ECnVs enabled the controlled release of vancomycin at a constant rate with zero-order kinetics, whereas liposomes exhibited first-order release kinetics. Moreover, ECnVs could be retained on both collagen-fibrin (co-gel) matrices and collagen-only matrices, with differential retention on the two biomaterials resulting in different local concentrations of released vancomycin. Overall, the biphasic release profiles of vancomycin from ECnVs/co-gel and ECnVs/collagen more effectively inhibited the growth of MRSA for 18 and 24 h, respectively, even after repeated bacterial inoculation, as compared to matrices containing free vancomycin, which just delayed the growth of MRSA. Thus, this newly developed antibiotic delivery system exhibited distinct advantages for controlled vancomycin delivery and prolonged antibacterial activity relevant to the treatment of wound infections.

A collagen-based theranostic wound dressing with visual, long-lasting infection detection capability

Continuous wound monitoring is one strategy to minimise infection severity and inform prompt variations in therapeutic care following infection diagnosis. However, integration of this functionality in therapeutic wound dressings is still challenging. We hypothesised that a theranostic dressing could be realised by integrating a collagen-based wound contact layer with previously demonstrated wound healing capability, and a halochromic dye, i.e. bromothymol blue (BTB), undergoing colour change following infection-associated pH changes (pH: 5-6 ➔ >7). Two different BTB integration strategies, i.e. electrospinning and drop-casting, were pursued to introduce long-lasting visual infection detection capability through retention of BTB within the dressing. Both systems had an average BTB loading efficiency of 99 wt% and displayed a colour change within 1 min of contact with simulated wound fluid. Drop-cast samples retained up to 85 wt% of BTB after 96 h in a near-infected wound environment, in contrast to the fibre-bearing prototypes, which released over 80 wt% of BTB over the same time period. An increase in collagen denaturation temperature (DSC) and red shifts (ATR-FTIR) suggest the formation of secondary interactions between the collagen-based hydrogel and the BTB, which are attributed to count for the long-lasting dye confinement and durable dressing colour change. Given the high L929 fibroblast viability in drop-cast sample extracts (92 %, 7 days), the presented multiscale design is simple, cell- and regulatory-friendly, and compliant with industrial scale-up. This design, therefore, offers a new platform for the development of theranostic dressings enabling accelerated wound healing and prompt infection diagnosis.

Evaluation of a chitosan dressing in the management of hard-to-heal wounds

It is vital that as tissue viability teams, we are constantly striving to improve service delivery, healing rates and positive patient outcomes. In 2021 the author's team were introduced to a unique bioactive microfibre gelling (BMG) dressing, MaxioCel®, which uses chitosan to maintain a cohesive structure to increase fluid handling, antimicrobial and wound-healing properties.

METHOD

Following Isle of Wight NHS Foundation Trust guidelines and with patient consent, 11 patients with chronic wounds of various aetiologies and wound durations were enrolled in a multicentre, clinical 4-week evaluation.

RESULTS

Over a 4-week evaluation period, all patients showed a significant improvement in wound healing parameters including average tissue type, condition of periwound skin, patient comfort, exudate levels. The assessments demonstrated a significant decrease in necrotic and sloughy tissue (from >75% at the start of treatment), replaced with healthy granulation and epithelial tissue (>80% by week 4). Significant reduction in pain score was also reported in all patients, with average pain score at the start of the evaluation reducing from 5.8 ± 2.7 to a score of 2.5 ± 1.9 within 3 weeks.

CONCLUSION

The complicated wounds seen in this study were previously non-healing and MaxioCel, with BMG technology, demonstrated both significant clinical improvement and a positive impact on patient quality of life within just 4 weeks, resulting in its addition to the team's woundcare formulary.

Larval Therapy and Larval Excretions/Secretions: A Potential Treatment for Biofilm in Chronic Wounds? A Systematic Review

Chronic wounds present a global healthcare challenge and are increasing in prevalence, with bacterial biofilms being the primary roadblock to healing in most cases. A systematic review of the to-date knowledge on larval therapy's interaction with chronic-wound biofilm is presented here. The findings detail how larval therapy-the controlled application of necrophagous blowfly larvae-acts on biofilms produced by chronic-wound-relevant bacteria through their principle pharmacological mode of action: the secretion and excretion of biologically active substances into the wound bed. A total of 12 inclusion-criteria-meeting publications were identified following the application of a PRISMA-guided methodology for a systematic review. The findings of these publications were qualitatively analyzed to provide a summary of the prevailing understanding of larval therapy's effects on bacterial biofilm. A further review assessed the quality of the existing evidence to identify knowledge gaps and suggest ways these may be bridged. In summary, larval therapy has a seemingly unarguable ability to inhibit and degrade bacterial biofilms associated with impaired wound healing. However, further research is needed to clarify and standardize the methodological approach in this area of investigation. Such research may lead to the clinical application of larval therapy or derivative treatments for the management of chronic-wound biofilms and improve patient healing outcomes at a time when alternative therapies are desperately needed.

Secretome of Adipose-Derived Stem Cells Cultured in Platelet Lysate Improves Migration and Viability of Keratinocytes

Chronic wounds depict a silent epidemic challenging medical professionals worldwide. Regenerative medicine uses adipose-derived stem cells (ADSC) in promising new therapies. In this study, platelet lysate (PL) as a xenogen-free substitute for foetal bovine serum (FBS) in ADSC culture was used to create an ADSC secretome containing cytokines for optimal wound healing conditions. The ADSC secretome was tested on keratinocytes for migrational behaviour and viability. Therefore, human ADSC were characterized under FBS (10%) and PL (5% and 10%) substitution, regarding morphology, differentiation, viability, gene and protein expression. ADSC were then cultured in 5% PL and their secretome was used for stimulation of keratinocyte migration and viability. To enhance the effect, ADSC were treated with Epithelial Growth Factor (EGF, 100 ng/mL) and hypoxia (1% O₂). In both PL and FBS groups, ADSC expressed typical stem cell markers. PL induced a significantly higher increase in cell viability compared to FBS substitution. ADSC secretome contained various beneficial proteins which enhance the wound healing capacity of keratinocytes. This could be optimized treating ADSC with hypoxia and EGF. In conclusion, the study shows that ADSC cultivated in 5% PL can effectively support wound healing conditions and can be considered as a promising new therapy for individual treatment of chronic wound disorders.

Nanomaterials and nanomaterials-based drug delivery to promote cutaneous wound healing

Various factors could damage the structure and integrity of skin to cause wounds. Nonhealing or chronic wounds seriously affect the well-being of patients and bring heavy burdens to the society. The past few decades have witnessed application of numerous nanomaterials to promote wound healing. Owing to the unique physicochemical characteristics at nanoscale, nanomaterials-based therapy has been regarded as a potential approach to promote wound healing. In this review, we first overview the wound categories, wound healing process and critical influencing factors. Then applications of nanomaterials with intrinsic therapeutic effect and nanomaterials-based drug delivery systems to promote wound healing are addressed in detail. Finally, current limitations and future perspectives of nanomaterials in wound healing are discussed.

SCI-QOL and WOUND-Q Have the Best Patient-reported Outcome Measure Design: A Systematic Literature Review of PROMs Used in Chronic Wounds

Chronic wounds are a significant burden on healthcare systems due to high costs of care (2%-4% total healthcare cost) and a considerable burden on patient's quality of life. Patient-reported outcome measures (PROMs) are questionnaires developed to enable patient self-assessments of their outcomes. A gap in knowledge exists because previous reviews on wound-specific PROMs did not evaluate the quality of the development. The main question is which PROM has the best quality development properties and should be used in clinical care and research.

Methods

PubMed, Embase, and CINAHL were searched from their inception through December 2021. Studies that included patients aged 18 years or older, with chronic wounds, and who reported using a condition-specific PROM for wounds were extracted. We excluded generic PROMs, comments, guidelines, and editorial letters. The COSMIN-guidelines were used to evaluate the quality of the PROMs.

Results

Of the 16,356 articles, a total of 251 articles describing 33 condition-specific PROMs for wounds were used. In total, 17 of 33 (52%) PROMs were developed for specific wound types, and nine of 33 (27%) PROMs were developed for any type of wound. Two of 33 (6%) PROMs were not rated because no development article was available. Only the SCI-QOL (Spinal Cord Injury-QOL) and the WOUND-Q rated "very good" in PROM design.

Conclusions

Thirty-three condition-specific PROMs were found. Only the SCI-QOL and the WOUND-Q rated very good in PROM design. The WOUND-Q is the only condition-specific PROM, which can be used in all types of chronic wounds in any anatomic location.

Bilayer nanofibrous wound dressing prepared by electrospinning containing gallic acid and quercetin with improved biocompatibility, antibacterial, and antioxidant effects

OBJECTEIVES

The purpose of this study was to prepare an antibacterial, antioxidant, and biocompatible bilayer nanofibrous wound dressing by using electrospinning.

METHODS

The micromorphology and bilayer structure characteristics of the GA-Qe-PVP-PCL nanofibers were analyzed by SEM. The physicochemical characteristics were analyzed by XRD and FTIR. The uptake, mechanical properties, water contact angle, water vapor transmission and in vitro drug release were evaluated. In addition, the effect of antibacterial, antioxidant and biocompatability of the nanofibers were evaluated, respectively.

RESULTS

The SEM results showed that the GA-Qe-PVP-PCL nanofibers had a smooth surface, no beading phenomenon, and a prominent bilayer structure. The diameter and porosity of the drug-loading layer and waterproof support layer of the nanofibers were 842 ± 302 nm, 242 ± 50 nm, and 88.56 ± 1.67%, 94.49 ± 1.57%, respectively. Moreover, the water uptake, mechanical properties, water contact angle, and water vapor transmission showed ideal performance. The results of in vitro drug release indicated that GA and Qe were both released rapidly, which was conducive to accelerating wound healing. The GA-Qe-PVP-PCL nanofibers exhibited antibacterial effects against both bacteria as well as high antioxidant activity. Additionally, the GA-Qe-PVP-PCL nanofibers possessed good compatibility, could promote the proliferation, adhesion, and migration of L929 fibroblast cells.

CONCLUSION

The nanofibers we developed met the requirements of ideal materials for wound dressing, which makes the nanofibers the potential to be a wound dressing for wound care.

Nutritional markers for predicting lower extremity free tissue transfer outcomes in the chronic wound population

BACKGROUND

Optimizing nutritional status is critical to maximize flap success and healing. Prealbumin and albumin have been utilized as easily obtained proxies for overall nutritional status. The aim of this study was to investigate whether these markers are correlated with healing time and overall flap healing after lower extremity (LE) free tissue transfer (FTT) in the chronic wound population.

METHODS

A retrospective review of LE chronic wound FTT patients treated by a single surgeon at our institution from 2011 to 2020 was performed. Data collected included demographics, comorbidities, flap characteristics, and perioperative labs. The outcomes of interest were flap healing (FH) and time to flap healing (TFH).

RESULTS

We identified 69 patients undergoing LE FTT for limb salvage meeting our inclusion criteria. When using a threshold of <3.5 g/dl for low albumin and < 20 mg/dl for low prealbumin, no significance was found between FH or TFH and preoperative albumin or preoperative prealbumin. With low albumin defined as <2.7 g/dl with the prealbumin threshold unchanged, TFH was significantly increased, and FH was significantly decreased compared with the defined normal preoperative albumin group.

CONCLUSIONS

Low preoperative albumin, when defined as <3.5 g/dl, and prealbumin did not correlate with TFH or FH. Contrarily, when defined as <2.7 g/dl, low preoperative albumin correlated significantly with increased TFH and decreased FH rates. Further investigation into validated biomarkers and their thresholds is needed to assess the effect of nutritional status on wound healing and guide perioperative optimization.

Specialized Nurse-led Care of Chronic Wounds During Hospitalization and After Discharge: A Randomized Controlled Trial

OBJECTIVE

To evaluate the effectiveness of specialized nurse-led care of patients with chronic wounds, provided both during hospitalization and postdischarge, on wound healing and readmission rates.

METHODS

An unblinded randomized controlled trial was conducted. Participants were patients with chronic wounds, randomly assigned to either the experimental group (cared for by wound care nurses both during hospitalization and postdischarge) or to the control group (cared for according to standard practice). Wound healing was identified as the primary outcome.

RESULTS

Overall, 1,570 patients were randomized, 1,298 of whom were included in the per-protocol analysis (707 in the experimental group and 591 in the control group). Nurse-led wound care quadrupled the probability of healing and reduced the number of treatment weeks and hospital readmissions.

CONCLUSIONS

Chronic wound care that was entrusted to specialized nurses improved outcomes in terms of wound healing, repair and regeneration, length of treatment, and rate of readmission, compared with standard practice. Future studies should evaluate the impact of care provided by specialized wound care nurses on patients' quality of life and healthcare costs. Nurse managers should promote the implementation of chronic wound clinical-care pathways entrusted to specialized nurses to improve patients' clinical outcomes and reduce hospital readmissions.

Molecular mechanism of VEGF and its role in pathological angiogenesis

Over the last seven decades, a significant scientific contribution took place in the delineation of the implications of vascular endothelial-derived growth factor (VEGF) in the processes of angiogenesis. Under pathological conditions, mainly in response to hypoxia or ischemia, elevated VEGF levels promote vascular damage and the growth of abnormal blood vessels. Indeed, the development of VEGF biology has revolutionized our understanding of its role in pathological conditions. Hence, targeting VEGF or VEGF-mediated molecular pathways could be an excellent therapeutic strategy for managing cancers and intraocular neovascular disorders. Although anti-VEGF therapies, such as monoclonal antibodies and small-molecule tyrosine kinase inhibitors, have limited clinical efficacy, they can still significantly improve the overall survival rate. This thus demands further investigation through the development of alternative strategies in the management of VEGF-mediated pathological angiogenesis. This review article focuses on the recent developments toward the delineation of the functional biology of VEGF and the role of anti-VEGF strategies in the management of tumor and eye pathologies. Moreover, therapeutic angiogenesis, an exciting frontier for the treatment of ischemic disorders, is highlighted in this review, including wound healing.

The basement membrane in epidermal polarity, stemness, and regeneration

The epidermis is a specialized epithelium that constitutes the outermost layer of the skin, and it provides a protective barrier against environmental assaults. Primarily consisting of multilayered keratinocytes, the epidermis is continuously renewed by proliferation of stem cells and the differentiation of their progeny, which undergo terminal differentiation as they leave the basal layer and move upward toward the surface, where they die and slough off. Basal keratinocytes rest on a basement membrane at the dermal-epidermal junction that is composed of specific extracellular matrix proteins organized into interactive and mechanically supportive networks. Firm attachment of basal keratinocytes, and their dynamic regulation via focal adhesions and hemidesmosomes, is essential for maintaining major skin processes, such as self-renewal, barrier function, and resistance to physical and chemical stresses. The adhesive integrin receptors expressed by epidermal cells serve structural, signaling, and mechanosensory roles that are critical for epidermal cell anchorage and tissue homeostasis. More specifically, the basement membrane components play key roles in preserving the stem cell pool, and establishing cell polarity cues enabling asymmetric cell divisions, which result in the transition from a proliferative basal cell layer to suprabasal cells committed to terminal differentiation. Finally, through a well-regulated sequence of synthesis and remodeling, the components of the dermal-epidermal junction play an essential role in regeneration of the epidermis during skin healing. Here too, they provide biological and mechanical signals that are essential to the restoration of barrier function.

Recent advances in nanomedicines for regulation of macrophages in wound healing

Macrophages are essential immune cells and play a major role in the immune response as pro-inflammatory or anti-inflammatory agents depending on their plasticity and functions. Infiltration and activation of macrophages are usually involved in wound healing. Herein, we first described macrophage polarization and their critical functions in wound healing process. It is addressed how macrophages collaborate with other immune cells in the wound microenvironment. Targeting macrophages by manipulating or re-educating macrophages in inflammation using nanomedicines is a novel and feasible strategy for wound management. We discussed the design and physicochemical properties of nanomaterials and their functions for macrophages activation and anti-inflammatory signaling during wound therapy. The mechanism of action of the strategies and appropriate examples are also summarized to highlight the pros and cons of those approaches. Finally, the potential of nanomedicines to modulate macrophage polarization for skin regeneration is discussed.

An exploration of public perceptions and attitudes towards maggot therapy

OBJECTIVE

The aim of the study was to explore public opinion and perceptions of maggot therapy (larval therapy), a treatment option for hard-to-heal wounds.

METHOD

The study used a mixed-method approach to obtain quantitative and qualitative data. A focus group was convened to explore opinions and views of maggot therapy with a small group of members of the public. Analysis of emerging themes from the focus group was used to design an anonymised web-based survey, which was made available online to members of the public through email and social media.

RESULTS

The focus group participants identified four key themes concerning the acceptability of maggot therapy. The subsequent online survey was completed by 412 participants, analysis of which revealed some worries and fears. Only 36% of survey participants agreed that they would accept maggot therapy as a first choice for a hypothetical painful wound, although this number increased with wound severity. The most predominant concerns regarding maggot therapy were sensation and a feeling of disgust associated with the therapy. However, participants could see some benefits to maggot therapy.

CONCLUSION

Our study showed that public perception of maggot therapy is varied. Survey participants expressed worries and fears associated with its use. However, positive relationships existed between knowledge scores and potential acceptability of maggot therapy, suggesting that information dissemination and education may be an important factor in public perception and acceptability of maggot therapy.

Regenerative Medicine to Improve Outcomes of Ventral Hernia Reconstruction (REPAIR Study) Phase 1: Find the Best Decellularization Protocol for the Human Dermis

Background: Tissue regeneration is a complex process that allows wounds to heal. Many options are currently available to help human skin repair and to reduce the recurrence of hernias. The aim of this study is to analyze the best decellularization protocol for allogenic human dermal tissues. Methods: Dermal flaps from donors were used and compared with a control group. Each flap was subjected to seven different decellularization protocols and washed with a sequence of five solutions. The samples were then subjected to four control tests (such as Nile Red), and long-term contacts were analyzed to assess whether the decellularized dermis samples could support the growth of human fibroblasts. Results: All the samples had an average residual viability of 60%. Except for one sample, the decellularization treatments were able to reduce cell viability significantly. The Nile Red test showed a significant reduction in phospholipid content (mean 90%, p-value < 0.05) in all treatments. The cell growth increased in a linear manner. As described in the literature, sodium-dodecyl-sulfate (SDS) caused an interference between the test and the detergent. Conclusions: This paper shows the first step to finding the best decellularization protocol for allografting human dermal tissues. Further biocompatibility tests and DNA quantification are necessary.

The Immediate Clinical Effects Following a Single Radial Shock Wave Therapy in Pressure Ulcers: A Preliminary Randomized Controlled Trial of The SHOWN Project

OBJECTIVE

Recent preliminary reports indicate that extracorporeal shock wave therapy (ESWT) might be useful for chronic wounds, especially venous leg ulcers (VLUs) and diabetic foot ulcers (DFUs). However, there is limited evidence for the utility and safety of ESWT in pressure ulcers (PUs). Therefore, this randomized controlled trial (RCT) aimed to assess immediate planimetric and clinical effects following a single radial ESWT session in PUs.

APPROACH

A group of 40 patients with PUs was randomly assigned into two groups: active ESWT (n=20), which underwent a single treatment with radial ESWT (300+100 impulses per 1 cm2, 2.5 bars, 0.15 mJ/mm2, and 5 Hz) and placebo ESWT (n=20) which was exposed to sham-radial ESWT. All patients continued standard wound care procedures. The planimetric assessment and clinical outcomes using Wound Bed Score (WBS) and Bates-Jansen Wound Assessment Tool (BWAT) were assessed before (M0) and after ESWT sessions (M1).

RESULTS

There was a significant planimetric enhancement observed after active ESWT reported as a reduction in all metric parameters: wound area from 11.51 cm2 to 8.09 cm2 (p<0.001), wound length from 4.97 cm to 4.41 cm (p<0.001), and wound width from 3.15 cm to 2.49 cm (p<0.0001). Also, there was a significant beneficial clinical improvement observed with a WBS as an increased score from 3.85 to 9.65 points (p<0.001) and with the BWAT as a decreased score from 45.45 to 30.70 points (p<0.001). In turn, a regression in the placebo ESWT group was observed in all studied outcomes.

INNOVATION

This study is the first RCT to provide the positive and immediate clinical effects of radial ESWT in promoting the healing of PUs.

CONCLUSION

This preliminary RCT showed that even a single session of ESWT is a promising and clinically effective modality in managing PUs. However, there is still limited data regarding the usefulness of ESWT in PUs, and further studies are in demand.

rhEGF-Loaded Hydrogel in the Treatment of Chronic Wounds in Patients with Diabetes: Clinical Cases

The aim of the study was to evaluate the healing process of chronic wounds treated with carboxymethylcellulose loaded with recombinant human epidermal growth factor in patients with diabetes. The case series consisted of 10 patients treated at the university hospital for 12 weeks. Data were analyzed using SPSS version 22.0. according to the intention to treat the principle, without the loss or exclusion of the participants. The sample consisted of 70% (7/10) males with a mean age of 61.9 years (±9.4); all (100%) had diabetes mellitus and 70% (7/10) had systolic hypertension associated with diabetes mellitus. Sixty percent (6/10) presented lesions of diabetic etiology and 40% (4/10) presented lesions of venous etiology; 70% (7/10) had had lesions for less than 5 years. The mean glycated hemoglobin was 7.8% (±2.7%), while the mean ankle-arm index (AAI) was 0.94 (±0.21). The mean initial area of all wounds was 13.4 cm², and the mean final area was 7.8 cm², with a reduction rate of 28.9% over the 12 weeks of treatment. The reduction rate of diabetic ulcers was higher (33.4%) than that of venous ulcers (22.1%). Regarding the type of tissue, there was an increase in granulation and epithelialization, and a decrease in slough and the amount of exudate that were statistically significant (p = 0.021). No participant had severe or local adverse events during the study period. Epidermal growth factor was effective in the treatment of chronic wounds, especially diabetic ulcers, resulting in the reduction of the wound area and the improvement of tissue and exudate quality.

Bacterial Interactions in the Context of Chronic Wound Biofilm: A Review

Chronic wounds, defined by their resistance to care after four weeks, are a major concern, affecting millions of patients every year. They can be divided into three types of lesions: diabetic foot ulcers (DFU), pressure ulcers (PU), and venous/arterial ulcers. Once established, the classical treatment for chronic wounds includes tissue debridement at regular intervals to decrease biofilm mass constituted by microorganisms physiologically colonizing the wound. This particular niche hosts a dynamic bacterial population constituting the bed of interaction between the various microorganisms. The temporal reshuffle of biofilm relies on an organized architecture. Microbial community turnover is mainly associated with debridement (allowing transitioning from one major representant to another), but also with microbial competition and/or collaboration within wounds. This complex network of species and interactions has the potential, through diversity in antagonist and/or synergistic crosstalk, to accelerate, delay, or worsen wound healing. Understanding these interactions between microorganisms encountered in this clinical situation is essential to improve the management of chronic wounds.

Filamentous bacteriophage delays healing of Pseudomonas-infected wounds

Chronic wounds infected by Pseudomonas aeruginosa (Pa) are characterized by disease progression and increased mortality. We reveal Pf, a bacteriophage produced by Pa that delays healing of chronically infected wounds in human subjects and animal models of disease. Interestingly, impairment of wound closure by Pf is independent of its effects on Pa pathogenesis. Rather, Pf impedes keratinocyte migration, which is essential for wound healing, through direct inhibition of CXCL1 signaling. In support of these findings, a prospective cohort study of 36 human patients with chronic Pa wound infections reveals that wounds infected with Pf-positive strains of Pa are more likely to progress in size compared with wounds infected with Pf-negative strains. Together, these data implicate Pf phage in the delayed wound healing associated with Pa infection through direct manipulation of mammalian cells. These findings suggest Pf may have potential as a biomarker and therapeutic target in chronic wounds.

A Review on Recent Progress of Stingless Bee Honey and Its Hydrogel-Based Compound for Wound Care Management

Stingless bee honey has a distinctive flavor and sour taste compared to Apis mellifera honey. Currently, interest in farming stingless bees is growing among rural residents to meet the high demand for raw honey and honey-based products. Several studies on stingless bee honey have revealed various therapeutic properties for wound healing applications. These include antioxidant, antibacterial, anti-inflammatory, and moisturizing properties related to wound healing. The development of stingless bee honey for wound healing applications, such as incorporation into hydrogels, has attracted researchers worldwide. As a result, the effectiveness of stingless bee honey against wound infections can be improved in the future to optimize healing rates. This paper reviewed the physicochemical and therapeutic properties of stingless bee honey and its efficacy in treating wound infection, as well as the incorporation of stingless bee honey into hydrogels for optimized wound dressing.

Wound Healing Activity of 80% Methanolic Crude Extract and Solvent Fractions of the Leaves of Justicia schimperiana (Hochst. ex Nees) T. Anderson (Acanthaceae) in Mice

Introduction

Justicia schimperiana has been used traditionally for the treatment of wound and skin burn, but there is no scientific evidence that supports the traditional claim.

Objective

To evaluate the wound healing activity of 80% methanol crude extract and solvent fractions of the leaves of Justicia schimperiana in mice.

Methods

Mice were used for wound healing study, while rats were used for acute dermal toxicity test. The 80% methanol crude extract and chloroform, ethyl acetate and aqueous fractions were formulated in ointments with 5% and 10% strength. Burn, excision and incision wound models were used to evaluate the effect of the crude extract, whereas the activity of the solvent fractions was evaluated using excision wound model. Parameters such as wound contraction, and period of epithelialization were studied in the excision and burn wound models, while tensile strength was measured in incision wound model.

Results

Treatment of wound with 80% methanol extract of Justicia schimperiana leaves using 5% (w/w) and 10% (w/w) ointment formulation induced significant (P<0.05) improvement in wound contraction rate, epithelialization time and skin breaking strength in excision, incision and burn wound model, respectively as compared to negative control. The chloroform, ethyl acetate and aqueous fractions with 5% (w/w) and 10% (w/w) ointment formulation showed significant (p<0.001) improvement in wound contraction and epithelialization time in excision wound model as compared to the negative control group.

Conclusion

This study has demonstrated that the 80% methanol crude extract and solvent fractions of Justicia schimperiana leaves possess wound healing activity.

Functional and Patient-reported Outcomes following Transmetatarsal Amputation in High-risk Limb Salvage Patients

Background

Transmetatarsal amputation (TMA) is performed in patients with nonhealing wounds of the forefoot. Compared with below-knee amputations, healing after TMA is less reliable, and often leads to subsequent higher-level amputation. The aim of this study was to evaluate the functional and patient-reported outcomes of TMA.

Methods

A retrospective review of patients who underwent TMA from 2013 to 2021 at our limb-salvage center was conducted. Primary outcomes included postoperative complications, secondary proximal lower extremity amputation, ambulatory status, and mortality. Univariate and multivariate analyses were performed to evaluate independent risk factors for higher-level amputation after TMA. Patient-reported outcome measures for functionality and pain were also obtained.

Results

A total of 146 patients were identified. TMA success was achieved in 105 patients (72%), and 41 patients (28%) required higher-level amputation (Lisfranc: 31.7%, Chopart: 22.0%, below-knee amputations: 43.9%). There was a higher incidence of postoperative infection in patients who subsequently required proximal amputation (39.0 versus 9.5%, P < 0.001). At mean follow-up duration of 23.2 months (range, 0.7-97.6 months), limb salvage was achieved in 128 patients (87.7%) and 83% of patients (n = 121) were ambulatory. Patient-reported outcomes for functionality corresponded to a mean maximal function of 58.9%. Pain survey revealed that TMA failure patients had a significantly higher pain rating compared with TMA success patients (P = 0.016).

Conclusions

TMA healing remains variable, and many patients will eventually require a secondary proximal amputation. Multi-institutional studies are warranted to identify perioperative risk factors for higher-level amputation and to further evaluate patient-reported outcomes.

Clinical Evaluation of the Efficacy and Tolerability of Rigenase® and Polyhexanide (Fitostimoline® Plus) vs. Hyaluronic Acid and Silver Sulfadiazine (Connettivina® Bio Plus) for the Treatment of Acute Skin Wounds: A Randomized Trial

OBJECTIVES

Compare the efficacy and tolerability of Connettivina® Bio Plus (Group A) gauze and cream, and Fitostimoline® Plus (Group B) gauze and cream for the treatment of acute superficial skin lesions.

DESIGN

Single-center, parallel, randomized trial. A block randomization method was used.

SETTING

University of Salerno-AOU San Giovanni di Dio e Ruggi d'Aragona.

PARTICIPANTS

Sixty patients were enrolled. All patients fulfilled the study requirements.

INTERVENTION

One application of the study drugs every 24 h, and a six-week observation period.

MAIN OUTCOME MEASURES

Efficacy and tolerability of the study drugs.

RESULTS

In total, 60 patients (Group A, n = 30; Group B, n = 30) were randomized; mean age was 58.5 ± 15.8 years. All patients were included in the outcome analysis. Total wound healing was achieved in 17 patients undergoing treatment with Connettivina® Bio Plus and 28 patients undergoing treatment with Fitostimoline® Plus. The greater effectiveness of the latter was significant (p = 0.00104). In Group B, a significantly greater degree of effectiveness was observed in reducing the fibrin in the wound bed (p = 0.04746). Complications or unexpected events were not observed.

CONCLUSIONS

Both Connettivina® Bio Plus and Fitostimoline® Plus are secure and effective for treating acute superficial skin lesions. Fitostimoline® Plus was more effective than Connettivina® Bio Plus in wound healing of acute superficial skin lesions, especially if fibrin had been observed in the wound bed.

Chronic Inflammation in Non-Healing Skin Wounds and Promising Natural Bioactive Compounds Treatment

Chronic inflammation is one of the hallmarks of chronic wounds and is tightly coupled to immune regulation. The dysregulation of the immune system leads to continuing inflammation and impaired wound healing and, subsequently, to chronic skin wounds. In this review, we discuss the role of the immune system, the involvement of inflammatory mediators and reactive oxygen species, the complication of bacterial infections in chronic wound healing, and the still-underexplored potential of natural bioactive compounds in wound treatment. We focus on natural compounds with antioxidant, anti-inflammatory, and antibacterial activities and their mechanisms of action, as well as on recent wound treatments and therapeutic advancements capitalizing on nanotechnology or new biomaterial platforms.

Resveratrol Microencapsulation into Electrosprayed Polymeric Carriers for the Treatment of Chronic, Non-Healing Wounds

Chronic, non-healing wounds represent a challenging socio-economic burden, demanding innovative approaches for successful wound management. Resveratrol (RSV) represents a promising therapeutic candidate, but its therapeutic efficacy and clinical applicability have been hampered by its rapid degradation and/or depletion. Herein, RSV was encapsulated into poly(ε-caprolactone) (PCL) microparticles by electrospraying with the aim to prolong and preserve RSV’s release/activity, without affecting its therapeutic properties. Electrospraying led to the fabrication of spherical (2 to 10 μm in size), negatively charged (<−1 mV), and quasi-monodisperse (PDI < 0.3) microparticles, with 60% RSV release after 28 days. Microencapsulation of RSV into PCL prevented its photochemical degradation and preserved its antioxidant properties over 72 h. The RSV-PCL microparticles did not exhibit any cytotoxicity on human dermal fibroblasts. RSV released from the microparticles was biologically functional and induced a significant increase in collagen type I deposition. Furthermore, the produced RSV-PCL microparticles reduced the expression of inflammatory (IL-6, IL-8, COX-2) and proteolytic (MMP-2, MMP-9) mediators. Collectively, our data clearly illustrate the potential of electrosprayed polymeric carriers for the sustained delivery of RSV to treat chronic wounds.

Electrical monitoring of infection biomarkers in chronic wounds using nanochannels

Chronic wounds represent an important healthcare challenge in developed countries, being wound infection a serious complication with significant impact on patients' life conditions. However, there is a lack of methods allowing an early diagnosis of infection and a right decision making for a correct treatment. In this context, we propose a novel methodology for the electrical monitoring of infection biomarkers in chronic wound exudates, using nanoporous alumina membranes. Lysozyme, an enzyme produced by the human immune system indicating wound infection, is selected as a model compound to prove the concept. Peptidoglycan, a component of the bacterial layer and the native substrate of lysozyme, is immobilized on the inner walls of the nanochannels, blocking them both sterically and electrostatically. The steric blocking is dependent on the pore size (20-100 nm) and the peptidoglycan concentration, whereas the electrostatic blocking depends on the pH. The proposed analytical method is based on the electrical monitoring of the steric/electrostatic nanochannels unblocking upon the specific degradation of peptidoglycan by lysozyme, allowing to detect the infection biomarker at 280 ng/mL levels, which are below those expected in wounds. The low protein adsorption rate and thus outstanding filtering properties of the nanoporous alumina membranes allowed us to discriminate wound exudates from patients with both sterile and infected ulcers without any sample pre-treatment usually indispensable in most diagnostic devices for analysis of physiological fluids. Although size and charge effects in nanochannels have been previously approached for biosensing purposes, as far as we know, the use of nanoporous membranes for monitoring enzymatic cleavage processes, leading to analytical systems for the specific detection of the enzymes has not been deeply explored so far. Compared with previously reported methods, our methodology presents the advantages of no need of neither bioreceptors (antibodies or aptamers) nor competitive assays, low matrix effects and quantitative and rapid analysis at the point-of-care, being also of potential application for the determination of other protease biomarkers.

Biofilm Survival Strategies in Chronic Wounds

Bacterial biofilms residing in chronic wounds are thought to have numerous survival strategies, making them extremely difficult to eradicate and resulting in long-term infections. However, much of our knowledge regarding biofilm persistence stems from in vitro models and experiments performed in vivo in animal models. While the knowledge obtained from such experiments is highly valuable, its direct translation to the human clinical setting should be undertaken with caution. In this review, we highlight knowledge obtained from human clinical samples in different aspects of biofilm survival strategies. These strategies have been divided into segments of the following attributes: altered transcriptomic profiles, spatial distribution, the production of extracellular polymeric substances, an altered microenvironment, inter-and intra-species interactions, and heterogeneity in the bacterial population. While all these attributes are speculated to contribute to the enhanced persistence of biofilms in chronic wounds, only some of them have been demonstrated to exist in human wounds. Some of the attributes have been observed in other clinical diseases while others have only been observed in vitro. Here, we have strived to clarify the limitations of the current knowledge in regard to this specific topic, without ignoring important in vitro and in vivo observations.

Advances in the Sensing and Treatment of Wound Biofilms

Wound biofilms represent a particularly challenging problem in modern medicine. They are increasingly antibiotic resistant and can prevent the healing of chronic wounds. However, current treatment and diagnostic options are hampered by the complexity of the biofilm environment. In this review, we present new chemical avenues in biofilm sensors and new materials to treat wound biofilms, offering promise for better detection, chemical specificity, and biocompatibility. We briefly discuss existing methods for biofilm detection and focus on novel, sensor-based approaches that show promise for early, accurate detection of biofilm formation on wound sites and that can be translated to point-of-care settings. We then discuss technologies inspired by new materials for efficient biofilm eradication. We focus on ultrasound-induced microbubbles and nanomaterials that can both penetrate the biofilm and simultaneously carry active antimicrobials and discuss the benefits of those approaches in comparison to conventional methods.

Advances in the Sensing and Treatment of Wound Biofilms

Wound biofilms represent a particularly challenging problem in modern medicine. They are increasingly antibiotic resistant and can prevent the healing of chronic wounds. However, current treatment and diagnostic options are hampered by the complexity of the biofilm environment. In this review, we present new chemical avenues in biofilm sensors and new materials to treat wound biofilms, offering promise for better detection, chemical specificity, and biocompatibility. We briefly discuss existing methods for biofilm detection and focus on novel, sensor-based approaches that show promise for early, accurate detection of biofilm formation on wound sites and that can be translated to point-of-care settings. We then discuss technologies inspired by new materials for efficient biofilm eradication. We focus on ultrasound-induced microbubbles and nanomaterials that can both penetrate the biofilm and simultaneously carry active antimicrobials and discuss the benefits of those approaches in comparison to conventional methods.

Enhancing the electrocatalytic activity of palladium nanocluster tags by selective introduction of gold atoms: Application for a wound infection biomarker detection

In this work, an unprecedented study exploring the role that slight changes into the Pd/Au proportion have in the electrocatalytic activity of bimetallic Pd-AuNPs toward the oxygen reduction reaction (ORR) is conducted. In particular, a careful control of the amount of Au atoms introduced in the cluster and the evaluation of the optimum Pd:Au ratio for getting the maximum catalytic activity is performed for the first time. First, PdNPs are synthesized by alcohol reduction in the presence of polyvinylpyrrolidone, and gold atoms are selectively introduced on vertex or corner positions of the cluster in different amounts following a galvanic substitution procedure. Average elemental analysis done relying on EDX spectroscopy allows to evaluate the Pd:Au ratio in the Pd-AuNPs obtained. Lineal sweep voltammetry and chronoamperometry are used for the evaluation of the Pd-AuNPs electrocatalytic activity toward ORR at a neutral pH compared to PdNPs and AuNPs alone. Our results indicate that, the synergy between both metals is strongly enhanced when the amount of gold is controlled and occupies the more reactive positions of the cluster, reaching a maximum activity for the NPs containing a 30% of gold, while an excess of this metal leads to a decrease in such activity, as a shelter of the PdNPs is achieved. Chronoamperometric analysis allows the quantification of the optimal Pd-AuNPs at over 6 × 10⁹ NPs/mL levels. Such optimal Pd-AuNPs were used as tags, taking advantage of the bio-functionalities of gold present in the cluster, in a proof-of-concept electrochemical immunosensor for the detection of hyaluronidase wound infection biomarker, using magnetic beads as platforms. Hyaluronidase was detected at levels as low as 50 ng/mL (0.02 U/mL; 437 U/mg) with good reproducibility (RSD below 8%) and selectivity (evaluated against bovine serum albumin, immunoglobulin G and lysozyme). The low matrix effects inherent to the use of magnetic bead platforms allowed us to discriminate between wound exudates with both sterile and infected ulcers without sample pre-treatment. This novel electrocatalytic immunoassay has the advantage, over common methods for NP tags electrochemical detection, of the signal generation in the same neutral medium where the immunoassay takes place (10 mM PBS pH 7.4), avoiding the use of additional and hazardous reagents, bringing it closer to their use as point-of-care devices. Overall, our findings may be of great interest not only for biosensing, but also for applications such as energy converting on fuel cells, in which the ORR has a pivotal role.

Healing Mechanisms in Cutaneous Wounds: Tipping the Balance

Acute and chronic cutaneous wounds pose a significant health and economic burden. Cutaneous wound healing is a complex process that occurs in four distinct, yet overlapping, highly coordinated stages: hemostasis, inflammation, proliferation, and remodeling. Postnatal wound healing is reparative, which can lead to the formation of scar tissue. Regenerative wound healing occurs during fetal development and in restricted postnatal tissues. This process can restore the wound to an uninjured state by producing new skin cells from stem cell reservoirs, resulting in healing with minimal or no scarring. Focusing on the pathophysiology of acute burn wounds, this review highlights reparative and regenerative healing mechanisms (including the role of cells, signaling molecules, and the extracellular matrix) and discusses how components of regenerative healing are being used to drive the development of novel approaches and therapeutics aimed at improving clinical outcomes. Important components of regenerative healing, such as stem cells, growth factors, and decellularized dermal matrices, are all being evaluated to recapitulate more closely the natural regenerative healing process.

Antiseptic Agents for Chronic Wounds: A Systematic Review

In many parts of the world, antiseptic agents remain non-indicated in chronic wound care. In the current context of bacterial resistance to antibiotics and the development of new-generation antiseptic agents, wound antisepsis represents an asset for the prevention of wound infection. We aimed to evaluate four common antiseptic agents in chronic wound care complete healing. The review protocol was based on the Cochrane Handbook for Systematic Reviews of Intervention and devised in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) statement guidelines. Five databases and three clinical trials registries were searched from inception to 30 June 2021 without language restrictions. We included randomised trials evaluating the efficacy of antiseptic agents in chronic wound care in adults. Interventions considered were those using antiseptics for cleansing or within a dressing. Risk of bias was assessed using the bias excel tool provided by the Bristol Academy. Evidence quality was assessed using Grading of Recommendation Assessment, Development and Evaluation (GRADE) criteria. Of 838 studies, 6 were finally included, with a total of 725 patients. The included studies assessed iodine (cadexomer or povidone iodine) (n = 3), polyhexanide (n = 2), and octenidine (n = 1). Limited evidence suggested a better wound healing completion with iodine compared to saline (two randomised controlled trials (RCT), 195 patients, pooled RR 1.85 (95%CI (1.27 to 2.69)), moderate-quality evidence). There was not enough evidence to suggest a difference in wound healing using octenidine or polyhexamide. None of the antiseptic agents influenced adverse event occurrence compared to saline.

Perception and Readiness to Undertake Maggot Debridement Therapy with the Use of Lucilia sericata Larvae in the Group of Nurses

The sight and smell of larvae in the wound may cause negative visual and olfactory impressions in sensitive individuals because of decaying body parts, carrion, and suffering. However, Maggot Debridement Therapy (MDT) is highly effective, safe, and cheap in wound healing and tissue revitalization for both the patient and health systems. The aim of the study was to assess the readiness to undertake MDT in a group of qualified nurses who perform therapeutic procedures in patients treated for chronic wounds. A diagnostic survey was used. The research tool was a scientific research protocol consisting of three questionnaires (sociodemographics, MDT perception questionnaire, pictures of wounds for visual assessment). The study included 290 nurses; the mean age was over 42.6 ± 9.9 years, and the median was 44 years. The perception and readiness to implement the method in the tested sample is at the average (standard) level. The image of maggots in the wound causes negative emotions among medical personnel. The higher the knowledge of the MDT method, the greater the motivation to implement it in practice.

Chronic wounds: Treatment consensus

The Wound Healing Foundation (WHF) recognised a need for an unbiased consensus on the best treatment of chronic wounds. A panel of 13 experts were invited to a virtual meeting which took place on 27 March 2021. The proceedings were organised in the sub-sections diagnosis, debridement, infection control, dressings, grafting, pain management, oxygen treatment, outcomes and future needs. Eighty percent or better concurrence among the panellists was considered a consensus. A large number of critical questions were discussed and agreed upon. Important takeaways included that wound care needs to be simplified to a point that it can be delivered by the patient or the patient's family. Another one was that telemonitoring, which has proved very useful during the COVID-19 pandemic, can help reduce the frequency of interventions by a visiting nurse or a wound care center. Defining patient expectations is critical to designing a successful treatment. Patient outcomes might include wound specific outcomes such as time to heal, wound size reduction, as well as improvement in quality of life. For those patients with expectations of healing, an aggressive approach to achieve that goal is recommended. When healing is not an expectation, such as in patients receiving palliative wound care, outcomes might include pain reduction, exudate management, odour management and/or other quality of life benefits to wound care.

Isolating and cryopreserving pig skin cells for single-cell RNA sequencing study

The pig skin architecture and physiology are similar to those of humans. Thus, the pig model is very valuable for studying skin biology and testing therapeutics. The single-cell RNA sequencing (scRNA-seq) technology allows quantitatively analyzing cell types, compositions, states, signaling, and receptor-ligand interactome at single-cell resolution and at high throughput. scRNA-seq has been used to study mouse and human skins. However, studying pig skin with scRNA-seq is still rare. A critical step for successful scRNA-seq is to obtain high-quality single cells from the pig skin tissue. Here we report a robust method for isolating and cryopreserving pig skin single cells for scRNA-seq. We showed that pig skin could be efficiently dissociated into single cells with high cell viability using the Miltenyi Human Whole Skin Dissociation kit and the Miltenyi gentleMACS Dissociator. Furthermore, the obtained single cells could be cryopreserved using 90% FBS + 10% DMSO without causing additional cell death, cell aggregation, or changes in gene expression profiles. Using the developed protocol, we were able to identify all the major skin cell types. The protocol and results from this study are valuable for the skin research scientific community.

Recent Advances on Bacterial Cellulose-Based Wound Management: Promises and Challenges

Wound healing is a therapeutic challenge due to the complexity of the wound. Various wounds could cause severe physiological trauma and bring social and economic burdens to the patient. The conventional wound healing treatments using bandages and gauze are limited particularly due to their susceptibility to infection. Different types of wound dressing have developed in different physical forms such as sponges, hydrocolloids, films, membranes, and hydrogels. Each of these formulations possesses distinct characteristics making them appropriate for the treatment of a specific wound. In this review, the pathology and microbiology of wounds are introduced. Then, the most recent progress on bacterial cellulose- (BC-) based wound dressing discussed and highlighted their antibacterial and reepithelization properties in vitro and in vivo wound closure. Finally, the challenges and future perspectives on the development of BC-based wound dressing biomaterials are outlined.

Role of copper nanoparticles in wound healing for chronic wounds: literature review

Chronic wounds are defined as wounds that fail to proceed through the normal phases of wound healing in an orderly and timely manner. The most common and inevitable impairment to wound healing is the installation of an infection, usually in the case of chronic wounds. Therefore, the objective of the present review was to identify the importance of copper nanoparticles in dressings for wound healing. Nanoparticles such as silver, gold and copper combat infectious processes through the inhibition of protein synthesis, peroxidation of the cell membrane and destroying the nucleic acids of bacteria and viruses. Among bioactive nanoparticles, copper plays a complex role in various cells, it modulates several cytokines and growth factor mechanisms of action and is essentially involved in all stages of the wound healing process. More importantly, copper plays a key role in skin regeneration and angiogenesis and accelerates the healing process through induction of vascular endothelial growth factor (VEGF) and angiogenesis by hypoxia-induced factor-1-alpha (HIF-1α) action where copper enhances HIF-1α expression and HIF-1α binding to the critical motifs in the promoter and putative enhancer regions of HIF-1-regulated genes.

Effects of Quercetin and Curcumin Combination on Antibacterial, Antioxidant, In Vitro Wound Healing and Migration of Human Dermal Fibroblast Cells

Wound healing impairment due to a postponed, incomplete, or uncoordinated healing process has been a challenging clinical problem. Much research has focused on wound care, particularly on discovery of new therapeutic approaches for acute and chronic wounds. This study aims to evaluate the effect of the combination of quercetin and curcuminoids at three different ratios on the antimicrobial, antioxidant, cell migration and wound healing properties. The antioxidant activities of quercetin, curcuminoids and the mixtures were tested by DPPH and ABTS free radical scavenging assays. The disc diffusion method was performed to determine the antibacterial activities of quercetin, curcuminoids and the mixtures against S. aureus and P. aeruginosa. The cytotoxicity and cell migratory enhancing effects of quercetin, curcuminoids and the mixtures against human dermal fibroblasts were investigated by MTT assay, scratch assay and Transwell migration assay, respectively. The results showed the synergism of the quercetin and curcuminoid combination to inhibit the growth of S. aureus and P. aeruginosa, with the inhibition zone ranging from 7.06 ± 0.25 to 8.78 ± 0.38 mm, respectively. The DPPH free radical scavenging assay demonstrated that the combination of quercetin and curcuminoids yielded lower IC₅₀ values (15.38–23.70 µg/mL) than curcuminoids alone (25.75 µg/mL). Quercetin and a 3:1 quercetin/curcuminoid mixture at non-toxic concentrations showed the ability to stimulate the migration of fibroblasts across the matrix, whereas only quercetin alone accelerated the wound closure of fibroblasts. In conclusion, the mixture of quercetin and curcuminoids at a 3:1 ratio was the best formulations for use in wound healing due to the antimicrobial, antioxidant and cell-migration-enhancing activities.

Feasibility of collecting wound fluid during ongoing negative pressure wound therapy by the use of an additional container - A prospective observational study

Negative‐pressure‐wound‐therapy is commonly used in clinical routine for wound management. Aim of the present study was to assess the feasibility and safety of using an additional container to collect wound fluid during ongoing negative‐pressure‐wound‐therapy. In this present prospective observational study, patients with negative‐pressure‐wound‐therapy were included. An additional container was inserted in the connecting tube between the wound and the vacuum generating device. The following 3 days, the container was changed daily and replaced by a new one. Further safety outcome parameters were assessed. A questionnaire was answered by the responsible surgeon. Twenty‐two patients with negative‐pressure‐wound‐therapy with a median (IQR) age of 58.5 (53.0‐70.0) years were included in the present study. In median, the duration of negative‐pressure‐wound‐therapy was 5.0 (4.6‐5.5) days. In mean ± SD the collected volume of the wound fluid in millilitres (mL) was on day one 7 ± 4 on day two 8 ± 7 and 10 ± 11 on day three. In one patient, there was <0.1 mL of clear water in the additional container. No safety concerns due to the additional container were observed. This study demonstrates that collecting wound fluid during ongoing negative‐pressure‐wound‐therapy over a time period of 3 days is feasible and safe. No safety concerns were observed.