Acute and impaired wound healing: pathophysiology and current methods for drug delivery, part 1: normal and chronic wounds: biology, causes, and approaches to care

Antimicrobial hybrid coatings: A review on applications of nano ZnO based materials for biomedical applications

The extreme survivability of infectious microorganisms on various surfaces prompts for the risk of disease transmissions, posing a perilous concern for global health. Thus, the treatment of these pathogenic microorganisms using the nanomaterials functionalized with antimicrobial coatings reaps relevant scope in the ongoing trend of research. Driven by their admirable biocompatibility, cost-effectiveness, and minimal toxicity, ZnO nanoparticles (ZnO-NPs) based antimicrobial hybrid coatings have emerged as a robust material to prevent the growth of infectious microorganisms on various surfaces, which in turn boosted their applications in the area of biomedical sciences. In this context, the current review focuses on the synthesis of ZnO-NPs based hybrid coatings using different polymers and inorganic materials for effective utilization in biomedical domains including dentistry, orthopedics, implantable medical devices and wound healing. The synergistic effect of ZnO-NPs hybrids with remarkable antibacterial, antifungal and antiviral property has been discussed. Finally, we highlight the future potential of ZnO-NPs based antimicrobial hybrid coatings for potential clinical translation.

Revealing the promising era of silk-based nanotherapeutics: a ray of hope for chronic wound healing treatment

Chronic wounds significantly contribute to disability and affect the mortality rate in diabetic patients. In addition, pressure ulcers, diabetic foot ulcers, arterial ulcers, and venous ulcers pose a significant health burden due to their associated morbidity and death. The complex healing process, environmental factors, and genetic factors have been identified as the rate-limiting stages of chronic wound healing. Changes in temperature, moisture content, mechanical strain, and genetics can result in slow wound healing, increased susceptibility to bacterial infections, and poor matrix remodelling. These obstacles can be addressed with natural biomaterials exhibiting antimicrobial, collagen synthesis, and granulation tissue formation properties. Recently, silk proteins have gained significant attention as a natural biomaterial owing to good biocompatibility, biodegradability, reduced immunogenicity, ease of sterilization, and promote the wound healing process. The silk components such as sericin and fibroin in combination with nano(platforms) effectively promote wound repair. This review emphasises the potential of sericin and fibroin when combined with nano(platforms) like nanoparticles, nanofibers, and nanoparticles-embedded films, membranes, gels, and nanofibers.

A review on smart dressings with advanced features

Wound care is a multifaceted and collaborative process, and chronic wounds can have significant repercussions on a patient's well-being and impose a financial burden on the healthcare industry. While traditional wound dressings can effectively facilitate healing, their limitations in addressing the intricacies of the wound healing process remain a formidable obstacle. Smart wound dressings have emerged as a promising solution to tackle this challenge, offering numerous advantages over conventional dressings, such as real-time monitoring of wound healing and enhanced wound care management. These advanced medical dressings incorporate microelectronic sensors that can monitor the wound environment and provide timely interventions for accelerated and comprehensive healing. Furthermore, advancements in drug delivery systems have enabled real-time monitoring, targeted therapy, and controlled release of medications. Smart wound dressings exhibit versatility, as they are available in various forms and can be utilised for treating different types of acute or chronic wounds. Ultimately, the development of innovative wound care technologies and treatments plays a vital role in addressing the complexities presented by wounds and enhancing patients' quality of life. This review sheds light on the diverse types of smart dressings and their distinctive features, emphasising their potential in advancing the field of wound care.

A sesbania gum/γ-polyglutamic acid photo-crosslinking composite hydrogel loaded with multi-component traditional Chinese medicine extract synergizes microenvironment amelioration in infected diabetic wound healing

The intricate physiological microenvironment of the diabetic wound characterized by overexpressed reactive oxygen species (ROS), persistent inflammation, angiogenetic dysfunction, and bacterial infection impeded the healing process. Herein, a photo-crosslinking composite hydrogel was fabricated based on the methacrylate modification of sesbania gum (SG) and γ-polyglutamic acid (γ-PGA), which could trigger free radical polymerization to form interpenetrating polymer network under 365 nm UV. Meanwhile, the micronized traditional Chinese medicine Huoxue Tongluo extract (HXTL) was encapsulated into the hydrogel to prepare the wound dressing (H-SGPGA). The 1H NMR and FT-IR successfully confirmed the synthesis of the methacrylate SG (SGMA) and γ-PGA (γ-PGAMA). Then, the enhanced mechanical properties, ROS scavenging (DPPH: 88.2 % ± 0.9 %; ABTS+: 90.5 % ± 0.4 %) and the antibacterial capacity (97.04 % ± 0.58 % against S. aureus) of H-SGPGA was investigated and confirmed in vitro. Finally, in the S. aureus infected diabetic wound model, the in vivo result demonstrated that the H-SGPGA significantly accelerated the diabetic wound repair process (8.31 % ± 5.54 % wound area on day 12) by promoting epidermis regeneration (79.13 % ± 5.99 %), collagen deposition (71.4 % ± 9.1 %), and angiogenesis (294.1 % ± 29.6 % of control group). Therefore, the composite H-SGPGA provided a potential treatment as the hydrogel dressing for the diabetic wound.

Development of hyaluronic acid-based hydrogels for chronic diabetic wound healing: A review

This research delves into the advancements in chronic skin wound treatment, with a particular focus on diabetic foot ulcers, utilizing hyaluronic acid (HA)-based hydrogels. Hyaluronic acid, an integral component of the skin's extracellular matrix, plays a crucial role in process such as inflammation, angiogenesis, and tissue regeneration. Due to their three-dimensional network structure, biocompatibility, hydrophilicity, and gas exchange capabilities, HA-based hydrogels are considered highly suitable for promoting wound healing. Nonetheless, pure HA hydrogels exhibit limitations including insufficient mechanical strength and rapid release of encapsulated substances. To address these limitations, the incorporation of bioactive materials such as chitosan and collagen was investigated. This combination not only optimized mechanical strength and degradation rates but also enhanced antibacterial and anti-inflammatory properties. Furthermore, responsive hydrogel dressings were developed to adapt to the specific characteristics of the diabetic wound microenvironment, enabling on-demand drug release. These advancements present new perspectives for the treatment of diabetic foot ulcers.

Efficacy of continuous topical oxygen therapy in hard-to-heal wounds in Colombia: a retrospective analysis

OBJECTIVE

To evaluate the use of continuous topical oxygen therapy (cTOT) in hard-to-heal or chronic wounds in Colombia, South America.

METHOD

This multicentre, retrospective analysis studied the efficacy of treating hard-to-heal wounds using a cTOT device in patients over a 3-6-month period. Data were collected retrospectively from patient records. Descriptive statistics were used to summarise the characteristics of the patient population, types of wounds and treatment outcomes. Patients were divided into two groups: a continuous cTOT-treated group (n=47) and a discontinuous cTOT-treated group (n=22). The duration of treatment and wound size reduction were compared. Changes in pain medication usage and the incidence of infections were also analysed.

RESULTS

A total of 69 patients were included in the analysis. Complete healing was achieved in 64% of the continuous cTOT-treated group and 36% of the discontinuous cTOT-treated group, with most patients being pain-free and not requiring medication after treatment.

CONCLUSION

The results of this study suggest the benefits of cTOT over traditional treatments in accelerating wound healing and reducing pain, medication necessity and wound infection.

Influence of anticoagulant concomitant medication on wound healing: Analysis of a multicentre cohort of 212 patients with a uniform wound model

AIMS

Various factors can impair wound healing by disrupting key stages of the process. This study evaluates the impact of concomitant anticoagulant medication on wound healing in a cohort of 212 patients.

METHODS

Data from 2 open-label, blindly evaluated, prospective, randomized, multicentre phase III trials (n = 212) were analysed. Healing durations of patients taking anticoagulants were compared to a control group (split-thickness skin graft donor site halves treated with standard moist wound dressing). Kaplan-Meier estimators and multivariable Cox regression were applied.

RESULTS

Kaplan-Meier analysis demonstrated significantly accelerated wound healing in patients treated with enoxaparin or nadroparin. Among monotherapies, 75% of patients on enoxaparin achieved wound closure within 16.5 days (95% confidence interval [CI]: 14-21), and those on nadroparin within 15 days (95% CI: 11.5-19), compared to 24 days (95% CI: 20-28) in patients receiving other anticoagulants (log-rank test: P < .001). Cox regression confirmed a significantly faster healing rate with enoxaparin or nadroparin (hazard ratio = 1.50, 95% CI: 1.02-2.19, P = .039).

CONCLUSION

Enoxaparin and nadroparin may enhance wound healing, whereas phenprocoumon, acetylsalicylic acid, and certain low-molecular-weight heparins (certoparin, tinzaparin, dalteparin, bemiparin) appear to delay wound healing. Anticoagulant monotherapy with enoxaparin or nadroparin should be considered postoperatively when feasible.

Inhibition of Th2 Differentiation Accelerates Chronic Wound Healing by Facilitating Lymphangiogenesis

Background/Objectives: Chronic wounds pose a significant healthcare burden, and there remains no effective animal model for study. We aimed to develop a mouse model of chronic wounds that remain open for at least 4 weeks and to investigate the role of the lymphatic system in wound healing. Methods: Full-thickness excisional wounds were created on the dorsal surface of mouse tails to simulate chronic wounds. Lymphatic drainage was assessed using FITC-dextran lymphangiography. Histology and immunofluorescence were used to analyze immune cell infiltration. The effect of inhibiting Th2 differentiation via IL-4 and IL-13 neutralization on wound closure was also evaluated. Results: Our chronic wound model was successful, and wounds remained open for 4 weeks. Impaired lymphatic drainage was observed extending beyond the wound area. Increased CD4+ T-helper cell infiltration and Th2 cell accumulation were observed in the impaired lymphatic drainage zone. Inhibition of IL-4 and IL-13 accelerated wound healing. Conclusions: Impaired lymphatic drainage and Th2-mediated inflammation contribute to delayed healing, and gradients of lymphatic fluid flow are associated with spatial differences in lymphangiogenesis. Targeting Th2 cytokines may offer a novel therapeutic approach for chronic wounds.

Prevalence and Mechanisms of Itch in Chronic Wounds: A Narrative Review

Itch is a commonly experienced problem by individuals with chronic wounds and greatly compromises their quality of life. Scratching can further hinder the wound healing process. Despite this being a clinically recognized issue, our knowledge of its exact prevalence in chronic wounds of different types and the molecular mechanisms driving it is limited. The multifactorial nature of wound itch makes its characterization particularly challenging. The present review is based on a thorough PubMed search, and it aims to provide an overview of existing evidence on the epidemiology, impact, and pathophysiology of wound itch, along with general recommendations on its management. Importantly, our work highlights the merit of screening chronic wound patients for associated pruritus and incorporating anti-itch measures in mainstream wound care.

Proangiogenic Cyclic Peptide Nanotubes for Diabetic Wound Healing

An intricate biochemical system of coordinated cellular reactions is involved in restoring damaged tissue after wounds. In chronic wounds, such as diabetic foot ulcers, poor angiogenesis is a common stumbling block due to elevated glucose levels, increased proteolytic enzyme activity, and decreased production of growth factors. While various strategies, including modulation of inflammatory cells, administration of growth factors, and therapies involving stem cells or genes, have been explored to promote angiogenesis, they often suffer from limitations such as poor biodistribution, immunological rejection, administration/dosing, and proteolytic instability. Glycosaminoglycans, such as heparan sulfate, facilitate growth factor interactions with their receptors to induce angiogenic signaling, but their exogenous administration is hindered by poor stability, low serum half-life, and immunogenicity. Cyclic peptides, known for their structural stability and specificity, offer a promising alternative for inducing angiogenesis upon functional modifications. In this work, we developed heparan sulfate (HS)-mimetic cyclic peptide nanotubes (CPNTs) grafted with bioactive groups to enhance angiogenesis without using exogenous growth factors, drugs, or supplements. These CPNTs incorporate glutamic acid, serine, and sulfonated lysine to mimic the functional groups in heparin. The sulfonated cyclic hexapeptide nanotubes developed from DPro-LTrp-DLeu-LSer-DGlu-LLys demonstrated significant proangiogenic activity in HUVECs under hyperglycemic conditions; enhanced endothelial cell motility, invasion, and tube formation; and upregulation of proangiogenic genes and proteins. These HS-mimicking nanotubes have shown a strong potential for promoting impaired angiogenesis, without incorporating exogenous growth factors, and show strong potential in treating diabetic wounds. To the best of our knowledge, this is the first report on the use of HS-mimetic proangiogenic cyclic peptide nanotubes for diabetic wound healing.

Cognition and quality of life in patients with a diabetes-related foot ulcer

AIM

This study aimed to compare cognitive function and quality of life (QoL) in individuals with diabetes and a diabetes-related foot ulcer (DFU) to a control group with diabetes and no active foot ulceration.

MATERIALS & METHODS

A cross-sectional case-control study was conducted between December 2022 and August 2024. Forty-two adults with diabetes and an active DFU were compared to forty age- and sex-matched controls with diabetes but no DFU. Cognitive function was assessed using the Trail Making Test (TMT), and QoL was measured using the EuroQol EQ-5D-5L. Statistical analyses included Mann-Whitney U tests, logistic regression, and correlation analyses to evaluate differences and associations between cognitive function and QoL.

RESULTS

Individuals with a DFU demonstrated significantly poorer cognitive function compared to controls, taking approximately twice as long to complete the TMT (p < 0.001). Both rote memory (TMT-A) and executive functioning (TMT-B) were significantly impaired in the DFU group. QoL scores were also significantly lower in the DFU group (p = 0.005), with a notable association between cognitive impairment and reduced QoL (p = 0.01, r = -0.29). Logistic regression indicated that longer TMT completion time was associated with 4.13 increased odds of DFU (p < 0.001).

CONCLUSIONS

Cognitive function is significantly impaired in individuals with DFU and is associated with poorer QoL. These findings highlight the need to integrate cognitive assessments into DFU management to optimise adherence and improve patient outcomes.

The design principle of natural polysaccharide hydrogels for promoting wound healing: a prospective review

Acute skin injuries and chronic non-healing wounds are common in daily life, posing significant physical trauma to patients and creating substantial social and economic burdens. Polysaccharide-based hydrogels not only maintain optimal moisture levels for wound recovery but also act as effective barriers against bacterial infection. Polysaccharides, with their unique properties such as biocompatibility, biodegradability, and non-toxicity, are promising materials for constructing hydrogels designed for wound healing. This review discusses wound physiology, key design factors for wound-healing hydrogels, and the fundamental principles of hydrogel gelation. It also provides an overview of the current applications of polysaccharide-based hydrogels-including those derived from hyaluronic acid, chitosan, sodium alginate, cellulose, glucose, and starch-as advanced wound dressings. Finally, the review outlines current challenges and future research directions for polysaccharide-based hydrogels in wound healing, aiming to inspire further exploration and innovation in this field.

Spray-drying-engineered CS/HA-bilayer microneedles enable sequential drug release for wound healing

High incidence and mortality rates of chronic wounds place a heavy burden on global healthcare systems. Achieving phased delivery of antimicrobial and regenerative drugs is crucial for promoting chronic wound healing. Herein, a microneedle (MN) patch with a biphasic release system was developed using a combination of solvent casting and spraying methods. Additionally, a copper/PDMS mold was introduced to address the issue of deformation in the chitosan material during drying on polydimethylsiloxane (PDMS). The MNs have a bilayer structure, with a hyaluronic acid (HA) coating loaded with doxycycline (DOX) for antibacterial action and a chitosan (CS) core loaded with vascular endothelial growth factor (VEGF) for promoting cell migration and proliferation. Notably, in vitro drug release studies showed that the coating drug was released by 98.8% within 10 hours, while the release of the core drug could be sustained for up to 70 hours. In vivo studies showed that chronic wounds on C57 mice treated with CS/HA-bilayer MNs achieved nearly complete healing by day 9. These wounds exhibited reduced inflammatory cell infiltration, increased epithelial tissue regeneration, and enhanced collagen deposition. This work integrates the staged management of bacterial infection and angiogenesis and offers promising prospects for enhancing chronic wound healing.

The role of hyperbaric oxygen therapy in the treatment of diabetic foot ulcers - A literature review

Diabetic Foot Ulcers (DFUs) are chronic foot wounds, in a person with diabetes, which are associated with peripheral arterial insufficiency and/or peripheral neuropathy of the lower limb. Recent UK audit figures report that approximately 50-60 % of DFUs remain unhealed after 12 weeks. Previous research has suggested that ischaemia plays a key role in the pathophysiology of many chronic wounds, including DFUs. For this reason, hyperbaric oxygen therapy (HOT) has been investigated. The study aimed to investigate 1) Current understanding of the physiology of normal wound healing and the pathological mechanisms that occur in DFUs to interrupt these processes; 2) Effectiveness of current DFU treatment approaches; 3) Effectiveness from clinical trials and meta-analyses for any demonstrated therapeutic benefits of HOT in the treatment of DFUs, 4) Patient selection criteria for HOT, and patients who stand to benefit most from treatment. The review found that wound healing is a complex process, involving many cells and signalling molecules, and it remains incompletely understood. However, current evidence suggests that hyperglycaemia, hypoxia, chronic inflammation (due to infection, immune-cell dysfunction or other causes), peripheral neuropathy, and macro- and micro-vascular dysfunction may all adversely affect DFU healing. The review found that current NICE guidelines do not approve HOT therapy in the UK for DFU's, despite encouraging clinical research findings. HOT shows theoretical promise and has been successfully used in the treatment of individual DFUs for several decades. Despite this, there remains a lack of strong clinical evidence of benefits to encourage HOT's wider use. The review found that there were four important patient selection criteria for HOT treatment, including glycaemic control, possible contraindications and complications associated with treatment, ulcer severity and resistance to first and second line treatments. The review concluded that further high-quality clinical research is needed to improve the evidence base.

Polyphenols in wound healing: unlocking prospects with clinical applications

Wound healing is a multifaceted, complex process that factors like aging, metabolic diseases, and infections may influence. The potentiality of polyphenols, natural compounds, has shown anti-inflammatory and antimicrobial properties in promoting wound healing and their potential applications in wound management. The studies reviewed indicate that polyphenols have multiple mechanisms that promote wound healing. This involves enhancing antioxidant defenses, reducing oxidative stress, modulating inflammatory responses, improving healing times, reducing infection rates, and enhancing tissue regeneration in clinical trials and in vivo and in vitro studies. Polyphenols have been proven to be effective in managing hard-to-heal wounds, especially in diabetic and elderly populations. Polyphenols have shown significant benefits in promoting angiogenesis and stimulating collagen synthesis. Polyphenol treatment has been demonstrated to have therapeutic effects in wound healing and chronic wound management. Their ability to regulate key healing processes makes them suitable for new wound care products and treatments. Future research should enhance formulations and delivery methods to optimize polyphenols' bioavailability and therapeutic efficacy in wound management approaches.

"Harnessing green synthesized zinc oxide nanoparticles for dual action in wound management: Antibiotic delivery and healing Promotion"

Wound infections are characterized by the invasion of microorganisms into bodily tissues, leading to inflammation and potentially affecting any type of wound, including surgical incisions and chronic ulcers. If left untreated, they can delay recovery and cause tissue damage. Healthcare providers face challenges in treating these infections, which necessitate efficient treatment plans involving microbiological testing and clinical evaluation. The effectiveness of conventional treatments like antibiotics is limited by resistance. Various forms of nanotechnology have been developed, each exhibiting unique properties that address particular issues with conventional therapies. Among all the Nanocarriers, zinc oxide nanoparticles (ZnO NPs), offer promising treatments for persistent wound infections. ZnO NPs possess strong antibacterial, antioxidant, anti-inflammatory, and anti-diabetic properties, making them suitable for wound care applications. These nanoparticles can be produced economically and environmentally using green synthesis techniques that minimize toxicity and are biocompatible. While chemical and physical techniques offer precise control over nanoparticle characteristics, they often involve hazardous substances and energy-intensive procedures. The antibacterial qualities, low toxicity, and biological compatibility of green-synthesized ZnO NPs make them a promising treatment for wound infections. Their use in scaffolds, drug delivery systems, and wound dressings provides a viable approach to combat antibiotic resistance and enhance wound treatment outcomes. Furthermore research is necessary to fully realize the benefits of ZnO NPs in clinical practice.

Tailored bioengineering and nanomedicine strategies for sex-specific healing of chronic wounds

Chronic wounds, defined by their prolonged healing process, significantly impair patients' quality of life and impose a hefty financial burden on healthcare systems worldwide. Sex- and gender-specific mechanisms regulate inflammation and infection, angiogenesis, matrix synthesis and cell recruitment. All of these processes contribute to cutaneous wound healing but remain largely understudied. This review aims to spotlight the innovative realm of bioengineering and nanomedicine, which is at the helm of revolutionizing complex chronic wound care. It underscores the significance of integrating patient sex into the development and (pre)clinical testing of these avant-garde treatment modalities, in order to enhance healing prospects for all patients regardless of sex. Moreover, we explore the representation of male and female patients in clinical trials of bioengineered and nanomedicine products. Finally, we examine the primary reasons for the historical neglect in translating sex-specific wound healing research into clinical practice and propose strategic solutions. By tackling these issues, the article advocates advanced treatment frameworks that could significantly improve healing outcomes for individuals of all sexes, thereby optimizing both efficacy and inclusivity in chronic wound management.

Copper-Based Nanozymes: Potential Therapies for Infectious Wounds

Bacterial infections are a significant obstacle to the healing of acute and chronic wounds, such as diabetic ulcers and burn injuries. Traditional antibiotics are the primary treatment for bacterial infections, but they present issues such as antibiotic resistance, limited efficacy, and potential side effects. This challenge leads to the exploration of nanozymes as alternative therapeutic agents. Nanozymes are nanomaterials with enzyme-like activities. Owing to their low production costs, high stability, scalability, and multifunctionality, nanozymes have emerged as a prominent focus in antimicrobial research. Among various types of nanozymes, metal-based nanozymes offer several benefits, including broad-spectrum antimicrobial activity and robust catalytic properties. Specifically, copper-based nanozymes (CuNZs) have shown considerable potential in promoting wound healing. They exhibit strong antimicrobial effects, reduce inflammation, and enhance tissue regeneration, making them highly advantageous for use in wound care. This review describes the dual functions of CuNZs in combating infection and facilitating wound repair. Recent advancements in the design and synthesis of CuNZs, evaluating their antimicrobial efficacy, healing promotion, and biosafety both in vitro and in vivo on the basis of their core components, are critically important.

Application of novel strategies in chronic wound management with focusing on pressure ulcers: new perspective

Invading blood cells, extracellular tissue, and soluble mediators all play important roles in the wound-healing process. There is a substantial global burden of disease and mortality attributable to skin defects that do not heal. About 1% to 2% of the population in industrialized nations suffers from chronic wounds that don't heal, despite healthcare breakthroughs; this condition is very costly, costing about $25 billion each year in the US alone. Amputation, infection (affecting as many as 25% of chronic wounds), sepsis, and dermal replacements are all consequences of conventional therapeutic approaches like growth factor therapy and diabetic foot ulcers account for 85% of lower limb amputations. Despite these obstacles, scientists are constantly looking for new ways to speed healing and close wounds. The unique immunomodulatory capabilities and multipotency of mesenchymal stem cells (MSCs) have made them a potential therapeutic choice in tissue engineering and regenerative medicine. Animal models of wound healing have shown that MSCs can speed up the process by as much as 40% through enhancing angiogenesis, modulating inflammation, and promoting fibroblast migration. Clinical trials provide more evidence of their effectiveness; for instance, one RCT found that, after 12 weeks, patients treated with MSCs had a 72% smaller wound size than those in the control group. This review offers a thorough examination of MSCs by combining the latest research with preclinical evidence. Highlighting their potential to transform treatment paradigms, it delves into their biological properties, how they work during regeneration and healing, and therapeutic usefulness in controlling chronic wounds.

Application of DynaCT biliary soft tissue reconstruction technology in diagnosis and treatment of hepatolithiasis

BACKGROUND

Hepatobiliary stone disease involves an intrahepatic bile duct stone that occurs above the confluence of the right and left hepatic ducts. One-step percutaneous transhepatic cholangioscopic lithotripsy (PTCSL) using the percutaneous transhepatic one-step biliary fistulation (PTOBF) technique enables the clearing of intrahepatic stones and the resolution of strictures. However, hepatolithiasis with associated strictures still has high residual and recurrence rates after one-step PTCSL. DynaCT can achieve synchronized acquisition with a flat-panel detector during C-arm rotation. The technical approach and application value of DynaCT biliary soft tissue reconstruction technology for the diagnosis and treatment of hepatolithiasis with bile duct stenosis were evaluated in this study.

AIM

To explore the value of DynaCT biliary soft tissue reconstruction technology for the diagnosis and treatment of hepatolithiasis with bile duct stenosis, and to assess the feasibility and effectiveness of the PTOBF technique guided by DynaCT biliary soft tissue reconstruction technology.

METHODS

The clinical data of 140 patients with complex biliary stenosis disease combined with bile duct stenosis who received PTOBF and were admitted to the First Affiliated Hospital of Guangzhou Medical University from January 2020 to December 2024 were collected. The patients were divided into two groups: DynaCT-PTOBF group (70 patients) and conventional PTOBF group (70 patients). These groups were compared in terms of the preoperative bile duct stenosis, location of the liver segment where the stone was located, intraoperative operative time, immediate stone retrieval rate, successful stenosis dilatation rate, postoperative complication rate, postoperative reoperation rate, stone recurrence rate, and stenosis recurrence rate.

RESULTS

DynaCT biliary soft tissue reconstruction technology was successfully performed in 70 patients. The DynaCT-PTOBF group had a higher detection rate of target bile ducts where bile duct stones and biliary strictures were located than the PTOBF group. Compared with the PTOBF group, the DynaCT-PTOBF group was characterized by a significantly greater immediate stone removal rate (68.6% vs 50.0%, P = 0.025), greater immediate stenosis dilatation success rate (72.9% vs 55.7%, P = 0.034), greater final stenosis release rate (91.4% vs 75.7%, P = 0.012), shorter duration of intraoperative hemorrhage (3.14 ± 2.00 vs 26.5 ± 52.1, P = 0.039), and lower incidence of distant cholangitis (2.9% vs 11.4%, P = 0.49). There were no significant differences between the two groups in terms of the final stone removal rate, reoperation rate, or long-term complication incidence rate.

CONCLUSION

DynaCT biliary soft tissue reconstruction technology guiding the PTOBF technique in patients with hepatolithiasis with bile duct stenosis is feasible and accurate. It may be beneficial for optimizing the preoperative evaluation of the PTOBF technique.

A systematic in vitro study of the effect of normoglycaemic and hyperglycaemic conditions on the biochemical and cellular interactions of clinically-available wound dressings with different physicochemical properties

Diabetic foot, leg ulcers and decubitus ulcers affect millions of individuals worldwide leading to poor quality of life, pain and in several cases to limb amputations. Despite the global dimension of this clinical problem, limited progress has been made in developing more efficacious wound dressings, the design of which currently focusses on wound protection and control of its exudate volume. The present in vitro study systematically analysed seven types of clinically-available wound dressings made of different biomaterial composition and engineering. Their physicochemical properties were analysed by infrared spectroscopy, swelling and evaporation tests and variable pressure scanning electron microscopy. These properties were linked to the interactions with inflammatory cells in simulated normoglycaemic and hyperglycaemic conditions. It was observed that the swelling behaviour and evaporation prevention at different glucose levels depended more on the engineering of the fibres than on the hydrophilicity and hydrophobicity of their biomaterials. Likewise, the data show that the engineering of the dressings as either non-woven or woven or knitted fibres seems to determine the swelling behaviour and interactions with inflammatory cells more than their polymer composition. Dressings presenting absorbent layers made of synthetic, non-woven fibres supported the adhesion of monocytes macrophages and stimulate the release of factors known to play a role in the chronic inflammation. Non-woven absorbent layers based on carboxymethyl cellulose mainly stimulating the iNOS, an enzyme producing free radicals; in the case of Kerracel this was combined with a swelling of fibres preventing the penetration of cells. Kaltostat, an alginate-based wound dressing, showed the higher level of swelling and supporte the adhesion of inflammatory cells with limited activation. Knitted dressings showed a limited adhesion of inflammatory cells. In conclusion, this work offers insights about the interactions of these wound dressings with inflammatory cells upon exudate changes thus providing further criteria of choice to clinicians.

Early experience on injectable micronized putty type human-derived acellular dermal matrix (ADM) in management of diabetic foot wounds in Singapore

Diabetic foot wounds (DFW) are notoriously difficult to treat owing to poor vascularity, delayed healing and higher rates of infection. Human-derived acellular dermal matrices (ADM) have been used in DFW treatment, utilizing a matrix scaffold for new tissue generation. We investigate the efficacy of a micronized injectable human-derived ADM in the treatment of DFW. We retrospectively recruited 13 patients with diabetic foot wounds. Wounds were adequately debrided, and a micronized injectable ADM was applied. Wound sizes were recorded prior to treatment, at 2 and 4 weeks post-treatment. The mean defect of wounds treated was 19.21 cm3. Our results showed a statistically significant reduction in wound size of 45% and 59% at 2 and 4 weeks post-treatment, respectively (p < 0.01). ADM was also effective in infected DFW as 84% of our wounds had positive tissue cultures at the time of application. Micronized injectable ADM has proven to be an effective treatment for DFW. Advantages include a ready-to-use injectable, single-stage treatment, minimal pain, mouldable matrix to fit any wound shape, allows for outpatient treatment and simple wound dressings.

Orchestration of Macrophage Polarization Dynamics by Fibroblast-Secreted Exosomes during Skin Wound Healing

Macrophages undertake pivotal yet dichotomous functions during skin wound healing, mediating both early proinflammatory immune activation and late anti-inflammatory tissue remodeling processes. The timely phenotypic transition of macrophages from inflammatory M1 to proresolving M2 activation states is essential for efficient healing. However, the endogenous mechanisms calibrating macrophage polarization in accordance with the evolving tissue milieu remain undefined. In this study, we reveal an indispensable immunomodulatory role for fibroblast-secreted exosomes in directing macrophage activation dynamics. Fibroblast-derived exosomes permitted spatiotemporal coordination of macrophage phenotypes independent of direct intercellular contact. Exosomes enhanced macrophage sensitivity to both M1 and M2 polarizing stimuli, yet they also accelerated timely switching from M1 to M2 phenotypes. Exosome inhibition dysregulated macrophage responses, resulting in aberrant inflammation and impaired healing, whereas provision of exogenous fibroblast-derived exosomes corrected defects. Topical application of fibroblast-derived exosomes onto chronic diabetic wounds normalized dysregulated macrophage activation to resolve inflammation and restore productive healing. Our findings elucidate fibroblast-secreted exosomes as remote programmers of macrophage polarization that calibrate immunological transitions essential for tissue repair. Harnessing exosomes represents a previously unreported approach to steer productive macrophage activation states with immense therapeutic potential for promoting healing in chronic inflammatory disorders.

Self-assembled Arginine-Glycine-Aspartic Acid Mimic Peptide Hydrogels as Multifunctional Biomaterials for Wound Healing

Clinical management of nonhealing ulcers requires advanced materials that can enhance wound closure rates without relying on the release of drugs or other growth factors to obviate systemic deleterious side effects. In our previous work, we synthesized an integrin-binding cell adhesive MNH2 {Fmoc-FFβAR(K)βA-NH2 consisting of an RGD mimic, [R(K)], with an amide terminus}, MOH {Fmoc-FFβAR(K)βA-OH consisting of an RGD mimic, [R(K)], with acid terminus}, and MR (Fmoc-FFβARGDβA-NH2 consisting of an RGD peptide, reference) with multifunctional activity. Here, we reported the synthesis, characterization, and performance of a reversed derivative, R-MNH2 (Fmoc-FFβA(K)RβA-NH2 consisting of an RGD mimic, [K(R)], with an amide terminus) of an antimicrobial cell adhesive peptide, MNH2. Both peptides (MNH2 and R-MNH2) were found to interact with αvβ3 integrin, as shown by docking studies; however, they differed in cell adhesive properties, hydrogel formation, and antimicrobial efficacy. Later, the wound healing ability of a series of RGD/RGD peptide mimics (MR, R-MNH2, MNH2, and MOH) was studied in a methicillin-resistant Staphylococcus aureus (MRSA)-infected Balb/c mouse model. All studied peptides showed cell adhesion and wound healing properties; however, only the amide-terminal RGD peptide mimic, MNH2, and its reversed derivative, R-MNH2, showed antimicrobial activity in both in vitro and in vivo studies. Of these, MNH2 showed the highest integrin-mediated spreading, migration, and proliferation of dermal cells in vitro as well as in vivo. Therefore, the MNH2 peptide mimic represents a paradigm shift in the development of dermoconductive strategies to treat chronic wounds.

Intelligent bacteria-targeting ZIF-8 composite for fluorescence imaging-guided photodynamic therapy of drug-resistant superbug infections and burn wound healing

Infected burn wounds are characterized by persistent drug-resistant bacterial infection coupled with an inflammatory response, impeding the wound-healing process. In this study, an intelligent nanoparticle system (CCM+TTD@ZIF-8 NPs) was prepared using curcumin (CCM), an aggregation-induced emission luminogens (TTD), and ZIF-8 for infection-induced wound healing. The CCM+TTD@ZIF-8 NPs showed multiple functions, including bacteria targeting, fluorescence imaging and pH response-guided photodynamic therapy (PDT), and anti-inflammatory. The positive charges of ZIF-8 NPs allowed the targeting of drug-resistant bacteria in infected wounds, thereby realizing fluorescence imaging of bacteria by emitting red fluorescence at the infected site upon blue light irradiation. The pH-responsive characteristics of the CCM+TTD@ZIF-8 NPs also enabled controllable CCM release onto the infected wound site, thereby promoting the specific accumulation of ROS at the infected site, with outstanding bactericidal efficacy against drug-resistant Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa) strains in vitro/in vivo. Additionally, due to the excellent bactericidal effect and anti-inflammatory properties of CCM+TTD@ZIF-8 NPs combined with blue light irradiation, the regeneration of epidermal tissue, angiogenesis, and collagen deposition was achieved, accelerating the healing process of infected burn wounds. Therefore, this CCM+TTD@ZIF-8 NPs with multifunctional properties provides great potential for infected burn wound healing.

Metal nanoparticles incorporated chitosan-based electrospun nanofibre mats for wound dressing applications: A review

Wound healing is a dynamic physiological process essential for regenerating skin and maintaining coherence in hypodermic tissues. Chitosan-based electrospun nanofibre wound dressings show great promise for expediting the integration of skin and tissues due to their nano-topographic, biodegradable, biocompatible, and antimicrobial properties. However, their moderate bactericidal efficacy and limited mechanical strength hinder their widespread clinical application. The incorporation of specific metal nanoparticles (MNPs) and the functionalization of chitosan have brought attention to their crucial role in wound healing applications, yielding promising results by enhancing antibacterial properties, cell proliferation, cell signaling, and the mechanical robustness of the materials. Chitosan naturally mitigates the cytotoxicity of the incorporated metal nanoparticles within the nanofibers. Chitosan and modified chitosan-based electrospun mats incorporated with metal nanoparticles demonstrate substantial potential for expediting wound healing. This review offers a comprehensive overview of recent advancements in electrospun chitosan-based mats containing MNPs aimed at enhancing wound healing. It covers various aspects, including modification techniques, fabrication methods, wound closure mechanisms, MNP release profiles, histological considerations, addresses existing challenges, and outlines potential future developments.

Smart chitosan-based nanofibers for real-time monitoring and promotion of wound healing

Timely healing of acute wounds and stopping wound chronicity are current and future priorities in wound therapy. It is urgent and relevant to develop a wound dressing that has antimicrobial and monitors the wound microenvironment in real time. In this study, quaternary ammonium chitosan (HTCC) was selected as the antimicrobial agent and CS/PEO/HTCC nanofiber membranes (CPHs) were prepared by electrostatic spinning technique. The nanofiber membrane (CPH91) with the best antimicrobial performance was screened by the disk diffusion method and drug susceptibility testing by dilution method, and its antimicrobial effect on S. aureus was better than that of E. coli. Subsequently, functional carbon dots (CDs) were synthesized by solvothermal method and doped into CPH91 nanofibers by electrospinning. A good linear relationship between pH value (5.0-8.0) and the fluorescence intensity of CDs was observed. In addition, the nanofibers (CPH91@CDs) had good morphology, hydrophilicity, and biocompatibility. Changes in fluorescence intensity of CPH91@CDs at different pH (5.0-8.0) were monitored and converted into RGB values that were linearly fitted to pH value. Finally, the potential of CPH91@CDs of improving wound healing and instantaneously controlling wound healing process was confirmed by an infected wound model (S. aureus) on the back of SD rats.

Advances in Metal and Metal Oxide Nanomaterials for Topical Antimicrobial Applications: Insights and Future Perspectives

Nanotechnology has seen significant growth in the past few decades, with the use of nanomaterials reaching a wide scale. Given that antimicrobial resistance is peaking, nanotechnology holds distinct potential in this area. This review discusses recent applications of metal and metal oxide nanoparticles as antibacterial, antifungal, and antiviral agents, particularly focusing on their topical applications and their role in chronic wound therapy. We explore their use in various forms, including coated, encapsulated, and incorporated in hydrogels or as complexes, proposing them as topical antimicrobials with promising properties. Some studies have shown that metal and metal oxide nanoparticles can exhibit cytotoxic and genotoxic effects, while others have found no such properties. These effects depend on factors such as nanoparticle size, shape, concentration, and other characteristics. It is essential to establish the dose or concentration associated with potential toxic effects and to investigate the severity of these effects to determine a threshold below which metal or metal oxide nanoparticles will not produce negative outcomes. Therefore, further research should focus on safety assessments, ensuring that metal and metal oxide nanoparticles can be safely used as therapeutics in biomedical sciences.

Mechanism of cold exposure delaying wound healing in mice

Cold temperatures have been shown to slow skin wound healing. However, the specific mechanisms underlying cold-induced impairment of wound healing remain unclear. Here, we demonstrate that small extracellular vesicles derived from cold-exposed mouse plasma (CT-sEVs) decelerate re-epithelialization, increase scar width, and weaken angiogenesis. CT-sEVs are enriched with miRNAs involved in the regulation of wound healing-related biological processes. Functional assays revealed that miR-423-3p, enriched in CT-sEVs, acts as a critical mediator in cold-induced impairment of angiogenic responses and poor wound healing by inhibiting phosphatase and poly(A) binding protein cytoplasmic 1 (PABPC1). These findings indicate that cold delays wound healing via miR-423-3p in plasma-derived sEVs through the inhibition of the ERK or AKT phosphorylation pathways. Our results enhance understanding of the molecular mechanisms by which cold exposure delays soft tissue wound healing.

A comprehensive review of the application of 3D-bioprinting in chronic wound management

INTRODUCTION

Chronic wounds require more sophisticated care than standard wound care because they are becoming more severe as a result of diseases like diabetes. By resolving shortcomings in existing methods, 3D-bioprinting offers a viable path toward personalized, mechanically strong, and cell-stimulating wound dressings.

AREAS COVERED

This review highlights the drawbacks of traditional approaches while navigating the difficulties of managing chronic wounds. The conversation revolves around employing natural biomaterials for customized dressings, with a particular emphasis on 3D-bioprinting. A thorough understanding of the uses of 3D-printed dressings in a range of chronic wound scenarios is provided by insights into recent research and patents.

EXPERT OPINION

The expert view recognizes wounds as a historical human ailment and emphasizes the growing difficulties and expenses related to wound treatment. The expert acknowledges that 3D printing is revolutionary, but also points out that it is still in its infancy and has the potential to enhance mass production rather than replace it. The review highlights the benefits of 3D printing for wound dressings by providing instances of smart materials that improve treatment results by stimulating angiogenesis, reducing pain, and targeting particular enzymes. The expert advises taking action to convert the technology's prospective advantages into real benefits for patients, even in the face of resistance to change in the healthcare industry. It is believed that the increasing evidence from in-vivo studies is promising and represents a positive change in the treatment of chronic wounds toward sophisticated 3D-printed dressings.

Skin Structure, Physiology, and Pathology in Topical and Transdermal Drug Delivery

Several industries are increasingly focused on enhancing the delivery of active ingredients through the skin to optimize therapeutic outcomes. By facilitating the penetration of active ingredients through the skin barrier, these enhancers can significantly improve the efficacy of various formulations, ranging from skincare products to therapeutic agents targeting systemic circulation. As the understanding of skin physiology and the mechanisms of drug absorption deepen, these industries are adopting permeation enhancers more widely, ultimately leading to better patient outcomes and expanded treatment options. However, the structure and physiological function of the skin can vary according to different factors, such as the area of the body and between individuals. These variations, along with external environmental exposures, aging and pathological conditions, introduce complexities that must be carefully considered when designing effective delivery systems. Considering the intricacies of skin structure and physiology, tailoring systems to account for regional differences, individual variability, and changes induced by environmental factors or disease is critical to optimizing therapeutic outcomes. This review discusses the features of skin structure, physiology, and pathologies, as well as the application of permeation enhancers in these contexts. Furthermore, it addresses the use of animal skin models in transdermal delivery and dermatological studies, along with the latest developments in this field.

An Update on Molecular Mechanisms of Scarring-A Narrative Review

Fibroblasts, the principal cellular mediators of connective tissue remodeling, play a crucial role in the formation of physiological and pathological scars. Understanding the intricate interplay between fibroblasts and other cellular and molecular components is essential for elucidating the underlying mechanisms driving scar formation. Hypertrophic scars, keloids and atrophic scars arise from dysregulated wound healing processes characterized by persistent inflammation, aberrant collagen deposition, and impaired extracellular matrix remodeling. Fibroblasts play a central role in the pathogenesis of such pathological scars, driving aberrant extracellular matrix remodeling, subsequently contributing to the formation of raised or depressed fibrotic lesions. The investigation of complex interactions between fibroblasts and the microenvironment is crucial for developing targeted therapeutic interventions aimed at modulating fibroblast activity and improving clinical outcomes in patients with pathological scars. Further research into the molecular pathways governing fibroblast behavior and their heterogeneity holds promise for advancing scar management strategies. This narrative review was performed to shed light on the mechanisms behind scar formation, with a special focus on the role of fibroblasts in the formation of different types of scars, providing insights into the pathophysiology of these conditions. Through the analysis of current knowledge, this review seeks to identify the key cellular and molecular mechanisms involved in fibroblast activation, collagen synthesis, and extracellular matrix remodeling in hypertrophic scar, keloid, or atrophic scar formation.

Homologous cell membrane-based hydrogel creates spatiotemporal niches to improve outcomes of dysregulated chronic wound healing

The (M2M + TGF-β)@HAMA hydrogel dressing improves the outcomes of dysregulated chronic wound healing by protecting the open wound from repeated bacterial infections, reprogramming endogenous monocytes and M1 macrophages into an M2-phenotype, as well as enhancing fibroblastic proliferation and migration for matrix remodeling and granulation tissue formation.Image 1.

The Impact of the Combination of Proteolytic Enzyme and Rutin on the Post-operative Management of Inflammation: A Randomized, Controlled, Double-Blind, Comparative Clinical Trial

Introduction Post-operative wound infections are a common complication that may impede recovery and require longer hospital stays. These infections substantially impact patient outcomes, increasing the likelihood of complications and healthcare expenses. Effective management of inflammation and pain is crucial for optimizing post-operative care. Method In this study, a total of 65 patients were randomized to either one of the three groups - EnMax tablet (Advanced Vital Enzymes Private Limited (ADVENZA), Thane, India) along with standard of care (SOC), Placebo tablet along with SOC, and Marketed reference preparation along with SOC. Follow-up visits were conducted on days 1, 3, 6, and 8. Results On day 8, EnMax demonstrated a statistically significant reduction in inflammation scores of 91.49%, compared to 80% with the marketed reference preparation and 63.64% with placebo. The EnMax group also showed a greater reduction in Visual Analog Scale (VAS) pain scores of 95.29% compared to the marketed reference preparation of 86.42%. Significant reductions in C-reactive protein (CRP) of 51.24% and erythrocyte sedimentation rate (ESR) at 59.80% were observed in the EnMax group, while the marketed reference preparation showed reductions of 35.23% and 46.38%, respectively. Both patient and investigator assessments favored EnMax over the marketed reference and placebo formulation. The study reported no adverse events, with stable vital signs and clinically insignificant changes in complete blood count (CBC), indicating the safety and tolerability of the investigational products. Conclusion EnMax, a combination of systemic microbial and plant proteases with the herbal component rutin, achieved significant reductions in post-operative inflammation, pain, and analgesic use, and improved overall patient and investigator assessment scores, outperforming placebo and demonstrating comparable, slightly superior efficacy to the marketed reference preparation. This study not only serves as a valuable guideline for current clinical practice in managing post-surgical inflammation and pain but also establishes a robust baseline for further research in postoperative care and other inflammatory conditions.

A pro-reparative bioelectronic device for controlled delivery of ions and biomolecules

Wound healing is a complex physiological process that requires precise control and modulation of many parameters. Therapeutic ion and biomolecule delivery has the capability to regulate the wound healing process beneficially. However, achieving controlled delivery through a compact device with the ability to deliver multiple therapeutic species can be a challenge. Bioelectronic devices have emerged as a promising approach for therapeutic delivery. Here, we present a pro-reparative bioelectronic device designed to deliver ions and biomolecules for wound healing applications. The device incorporates ion pumps for the targeted delivery of H+ and zolmitriptan to the wound site. In vivo studies using a mouse model further validated the device's potential for modulating the wound environment via H+ delivery that decreased M1/M2 macrophage ratios. Overall, this bioelectronic ion pump demonstrates potential for accelerating wound healing via targeted and controlled delivery of therapeutic agents to wounds. Continued optimization and development of this device could not only lead to significant advancements in tissue repair and wound healing strategies but also reveal new physiological information about the dynamic wound environment.

Evaluation of Full Thickness Wounds Following Application of a Visco-Liquid Hemostat in a Swine Model

Wound healing is a complex dynamic biomechanical process as the body attempts to restore the integrity of traumatized or devitalized tissues. There are four stages of wound of healing that begins with hemostasis followed by inflammation, proliferation and finally weeks later wound remodeling. Full thickness wounds usually are covered with a dressing material after hemostasis, which allows for controlled hydration. We investigated the potential of a visco-liquid hemostat, polyhedral oligomeric silsesquioxane (POSS), for providing hemostasis and to maintain a microenvironment in the wound bed that would maintain moisture content and promote early re-epithelialization. We hypothesized that the hemostatic agent POSS if left in the wound bed would maintain a protective barrier and accelerate wound healing similar to using saline to irrigate the wound to keep the wound moist. We compared the early phase of wound repair (3-7 days) in a porcine full thickness wound model to evaluate the efficacy of the material. Biopsies were taken after 3 and 7 days to determine the acute response of the POSS hemostat or saline on inflammation, cell migration, concentrations of metalloproteinase (MMPs), and tissue inhibitors of metalloproteinase (TIMPs). Accelerated healing was observed in POSS treated wounds by changes in wound contraction, keratinocyte migration, and development of granulation tissue in comparison to saline treated wounds. Increased concentrations at day 3 of MMP-2, MMP-3, and in MMP-1 at day 7 in POSS treated wounds compared to saline coincide with keratinocyte migration observed in the tissue histology and changes in wound contraction. Tissue concentrations of TIMP-1 and TIMP-2 in POSS treated wounds appear to coordinate the sequence of MMP events in the healing tissue. Matrix metalloproteinase-13, a marker for tissue remodeling, was not upregulated in the early wound healing cascade in either POSS or saline treated wounds at 3 or 7 days. Overall, the data suggests POSS treatment contributed to enhanced early cell migration and wound closure compared to saline treatment.

Self-Assembled Fibroblast Growth Factor Nanoparticles as a Therapeutic for Oxidant-Induced Neuronal and Skin Cell Injury

Traumatic brain injury (TBI) and spinal cord injury (SCI) are neurological conditions that result from immediate mechanical injury, as well as delayed injury caused by local inflammation. Furthermore, TBI and SCI often lead to secondary complications, including pressure wounds of the skin, which can heal slowly and are prone to infection. Pressure wounds are localized areas of damaged tissue caused by prolonged pressure on the skin due to immobility and loss of neurological sensation. With the aim to ameliorate these symptoms, we investigated whether fibroblast growth factors 2 (FGF-2) could contribute to recovery. FGF-2 plays a significant role in both neurogenesis and skin wound healing. We developed a recombinant fusion protein containing FGF-2 linked to elastin-like polypeptides (FGF-ELP) that spontaneously self-assembles into nanoparticles at around 33 °C. The nanoparticle's size was ranging between 220 and 250 nm in diameter at 2 μM. We tested this construct for its ability to address neuronal and skin cell injuries. Hydrogen peroxide was used to induce oxidant-mediated injury on cultured neuronal cells to mimic the impact of reactive oxidants released during the inflammatory response in vivo. We found that FGF-ELP nanoparticles protected against hydrogen peroxide-mediated injury and promoted neurite outgrowth. In the skin cell models, cells were depleted from serum to mimic the reduced levels of nutrients and growth factors in chronic skin wounds. FGF-ELP increased the proliferation and migration of human keratinocytes, fibroblasts, and endothelial cells. FGF-ELP is, therefore, a potentially useful agent to provide both neuroprotection and promotion of cellular processes involved in skin wound healing.

Research Progress of Hydrogel Microneedles in Wound Management

Microneedles are a novel drug delivery system that offers advantages such as safety, painlessness, minimally invasive administration, simplicity of use, and controllable drug delivery. As a type of polymer microneedle with a three-dimensional network structure, hydrogel microneedles (HMNs) possess excellent biocompatibility and biodegradability and encapsulate various therapeutic drugs while maintaining drug activity, thus attracting significant attention. Recently, they have been widely employed to promote wound healing and have demonstrated favorable therapeutic effects. Although there are reviews about HMNs, few of them focus on wound management. Herein, we present a comprehensive overview of the design and preparation methods of HMNs, with a particular emphasis on their application status in wound healing, including acute wound healing, infected wound healing, diabetic wound healing, and scarless wound healing. Finally, we examine the advantages and limitations of HMNs in wound management and provide suggestions for future research directions.

A novel chlorin derivative Shengtaibufen (STBF) mediated photodynamic therapy combined with iodophor for the treatment of chronic superficial leg wounds infected with methicillin-resistant Staphylococcus aureus: A retrospective clinical study

OBJECTIVE

Chronic wounds are costly and difficult to treat, resulting in morbidity and even mortality in some cases due to a high methicillin-resistant Staphylococcus aureus (MRSA) burden contributing to chronicity. We aimed to observe the antimicrobial activity and healing-promoting effect of a novel photosensitizer Shengtaibufen (STBF)-mediated antibacterial photodynamic therapy (PDT) on MRSA-infected chronic leg ulcers.

PATIENTS AND METHODS

This was a retrospective, comparative, single-center clinical study. A total of 32 patients with chronic lower limb wounds infected with MRSA from January 2022 to December 2023 were finally included in this study by searching the electronic medical records of the dermatology department of Huadong Hospital, including a group of red light combined with iodophor (control+iodophor, n=16, receiving red light once a week for 8 weeks and routine dressing change with iodophor once a day) and a group of STBF-mediated PDT (STBF-PDT) combined with iodophor (STBF-PDT+iodophor, n=16, receiving STBF-PDT and routine dressing change with iodophor once a day). STBF-PDT was performed once a week (1 mg/ml STBF, 1 h incubation, 630 nm red light, 80 J/cm2) for 8 weeks. The primary endpoints included wound clinical signs, wound size, wound-related pain, re-epithelialization score, MRSA load and wound-related quality of life (wound-QoL). Any adverse events were also recorded.

RESULTS

We found that STBF-PDT+iodophor could effectively alleviate clinical infection symptoms, accelerate wound closure, reduce average biological burden and improve wound-QoL without severe adverse events in comparison to the control+iodophor group. The STBF-PDT+iodophor group obtained a mean percentage reduction of 65.22% in wound size (from 18.96±11.18 cm2 to 6.59±7.94 cm2) and excellent re-epithelialization scores, as compared with a decrease of 30.17% (from 19.23±9.80 cm2 to 13.43±9.32 cm2) for the control+iodophor group. Significant differences in wound area were observed at week 6 (p=0.028*) and week 8 (p=0.002**). The bacterial load decreased by 99.86% (from 6.45 × 107±2.69 × 107 to 8.94 × 104±1.92 × 105 CFU/cm2, p<0.0001) in the STBF-PDT+iodophor group and 1.82% (from 6.61 × 107±2.13 × 107 to 6.49 × 107±2.01 × 107 CFU/cm2, p=0.029) in the control+iodophor group. The wound-QoL in STBF-PDT+iodophor group had a 51.62% decrease in overall score (from 29.65±9.33 at the initial to 14.34±5.17 at week 8, p<0.0001) compared to those receiving red light and routine wound care (from 30.73±17.16 to 29.32±15.89 at week 8, p=0.003). Moreover, patients undergoing STBF-PDT+iodophor exhibited great improvements in all domains of wound-QoL (physical, psychological and everyday-life), whereas the control+iodophor group ameliorated in only one field (everyday-life).

CONCLUSION

Our data confirmed that a novel photosensitizer, STBF-mediated PDT, when combined with iodophor, served as a potential modality for MRSA infection and a possible therapy for other drug-resistant microorganisms, and as a promising alternative for chronic cutaneous infectious diseases.

Teicoplanin-Decorated Reduced Graphene Oxide Incorporated Silk Protein Hybrid Hydrogel for Accelerating Infectious Diabetic Wound Healing and Preventing Diabetic Foot Osteomyelitis

Developing hybrid hydrogel dressings with anti-inflammatory, antioxidant, angiogenetic, and antibiofilm activities with higher bone tissue penetrability to accelerate diabetic wound healing and prevent diabetic foot osteomyelitis (DFO) is highly desirable in managing diabetic wounds. Herein, the glycopeptide teicoplanin is used for the first time as a green reductant to chemically reduce graphene oxide (GO). The resulting teicoplanin-decorated reduced graphene oxide (rGO) is incorporated into a mixture of silk proteins (SP) and crosslinked with genipin to yield a physicochemically crosslinked rGO-SP hybrid hydrogel. This hybrid hydrogel exhibits high porosity, self-healing, shear-induced thinning, increased cell proliferation and migration, and mechanical properties suitable for tissue engineering. Moreover, the hybrid hydrogel eradicates bacterial biofilms with a high penetrability index in agar and hydroxyapatite disks covered with biofilms, mimicking bone tissue. In vivo, the hybrid hydrogel accelerates the healing of noninfected wounds in a diabetic rat and infected wounds in a diabetic mouse by upregulating anti-inflammatory cytokines and downregulating matrix metalloproteinase-9, promoting M2 macrophage polarization and angiogenesis. The implantation of hybrid hydrogel into the infected site of mouse tibia improves bone regeneration. Hence, the rGO-SP hybrid hydrogel can be a promising wound dressing for treating infectious diabetic wounds, providing a further advantage in preventing DFO.

Homogenized and Lyophilized Amniotic Membrane Dressings for the Treatment of Diabetic Foot Ulcers in Ambulatory Patients

BACKGROUND

Diabetic foot ulcers (DFUs) constitute a complication that occurs in 19% to 34% of patients with diabetes mellitus (DM). The aim of this study is to describe median days to healing, average velocity of wound closure, and percentage of wound surface closed at 3, 6, and 12 weeks through the use of homogenized and lyophilized amniotic membrane (hAMpe) dressings for the treatment of DFUs in ambulatory patients.

METHODS

An observational, descriptive, longitudinal study was performed. Patients presenting with granulation-based DFU, after proper debridement, were included from August 19, 2021, until July 14, 2023. hAMpe dressings placed every 3 days were used for the treatment of these ulcers.

RESULTS

Sixteen patients were included with a mean age of 52.38 (8.07) years. The analyzed lesions were postsurgical ulcers in 15 of the 16 included patients. Median ulcer size was 19.5 cm2 (6.12-36). The median ABI was 1.10 (1-1.14). The median days to healing was 96 (71-170). The median percentage closure of the wound at 3 weeks was 41% (28.9%-55.3%), at 6 weeks it was 68.2% (48.6%-74.2%), and at 12 weeks it was 100% (81%-100%). The average velocity closure was 1.04% per day (95% CI 0.71%-1.31%). It was higher during the closure of the first 50% of the ulcer, 2.12% per day (95% CI 0.16%-4.09%), and decreased from 50% to 25% of the ulcer size to 0.67% per day (95% CI 0.23%-1.10%) and from 25% to closure to 0.47% per day (95% CI 0.14%-0.80%), P < .001.

CONCLUSION

These results are difficult to compare to other studies given the higher surface area of the ulcers included in our sample. The development of hAMpe dressings enables patients to apply them without requiring assistance from health care teams and was not associated with any recognized complications.

Unveiling the Unexplored Multifactorial Potential of 5-Aminosalicylic Acid in Diabetic Wound Therapy

Diabetic wounds (DWs) are considered chronic complications observed in patients suffering from type 2 diabetes mellitus (DM). Usually, DWs originate from the interplay of inflammation, oxidation, impaired tissue re-epithelialization, vasculopathy, nephropathy, and neuropathy, all of which are related to insulin resistance and sensitivity. The conventional approaches available for the treatment of DWs are mainly confined to the relief of wound pressure, debridement of the wound, and management of infection. In this paper, we speculate that treatment of DWs with 5-aminosalicylic acid (5-ASA) and subsequent activation of peroxisome proliferator-activated receptor gamma (PPAR-γ) and transforming growth factor beta (TGF-β) via the AhR pathway might be highly beneficial for DW patients. This estimation is based on several lines of evidence showing that 5-ASA and PPAR-γ activation are involved in the restoration of insulin sensitivity, re-epithelialization, and microcirculation. Additionally, 5-ASA and TGF-β activate inflammation and the production of pro-inflammatory mediators. Suitable stabilized formulations of 5-ASA with high absorption rates are indispensable for scrutinizing its probable pharmacological benefits since 5-ASA is known to possess lower solubility profiles because of its reduced permeability through skin tissue. In vitro and in vivo studies with stabilized formulations and a control (placebo) are mandatory to determine whether 5-ASA indeed holds promise for the curative treatment of DWs.

Review of Malaysian medicinal plants with potential wound healing activity

Wound is defined as the damage to biological tissues including skin, mucous membranes and organ tissues. The acute wound heals in less than 4 weeks without complications, while a chronic wound takes longer than 6 weeks to heal. Wound healing occurs in 4 phases, namely, coagulation, inflammatory, proliferative and remodeling phases. Triclosan and benzalkonium chloride are commonly used as skin disinfectants in wound healing. However, they cause allergic contact dermatitis and antibiotic resistance. Medicinal plants are widely studied due to the limited availability of wound healing agents. The present review included six commonly available medicinal plants in Malaysia such as Aloe barbadensis Miller, Carica papaya Linn., Centella asiatica Linn., Cymbopogon nardus Linn., Ficus benghalensis Linn. and Hibiscus rosa sinensis Linn. Various search engines and databases were used to obtain the scientific findings, including Google Scholar, ScienceDirect, PubMed Central and Research Gate. The review discussed the possible mechanism of action of medicinal plants and their active constituents in the wound healing process. In addition, their application in nanotechnology and wound dressings was also discussed in detail.

Design of chitosan-based drug-loaded laminated materials with superhydrophilic/superhydrophobic properties for simultaneous effective hemostasis and antiadhesion

Hemostatic materials play a crucial role in trauma medicine. However, existing materials have poor hemostatic efficacy and a tendency to adhere to the wound surface, limiting their clinical effectiveness. Herein, a drug-loaded, superhydrophilic/superhydrophobic laminated material (DSLM), consisting of a superhydrophobic inner layer with a micropore array, a superhydrophilic chitosan-based sponge layer loaded with hemostatic/antimicrobial drugs, and a superhydrophobic outer layer, was developed. Furthermore, the DSLM allows unidirectional flow of blood and exudates from the wound bed through the superhydrophobic inner layer while facilitating efficient drug delivery. In addition, it possesses excellent biocompatibility and antiadhesion properties, as confirmed by in vivo and in vitro experiments. Compared with traditional hemostatic materials, the DSLM remarkably increased the survival time by over threefold in the acute femoral transaction wound bleeding model, and simultaneously prevented secondary wound damage by reducing peeling force to one-eighth incomparison to pristine gauze. The DSLM holds promise as a versatile clinical biomaterial for prehospital acute trauma treatment, with its simple structure facilitating manufacturing and expanding applications in biomedicine.

Antibacterial polylysine-containing hydrogels for hemostatic and wound healing applications: preparation methods, current advances and future perspectives

The treatment of various types of wounds such as dermal wounds, multidrug resistant bacteria-infected wounds, and chronic diabetic wounds is one of the critical challenges facing healthcare systems. Delayed wound healing can impose a remarkable burden on patients and health care professionals. In this case, given their unique three-dimensional porous structure, biocompatibility, high hydrophilicity, capability to provide a moist environment while absorbing wound exudate, permeability to both gas and oxygen, and tunable mechanical properties, hydrogels with antibacterial function are one of the most promising candidates for wound healing applications. Polylysine is a cationic polymer with the advantages of inherent antibacterial properties, biodegradability, and biocompatibility. Therefore, its utilization to engineer antibacterial hydrogels for accelerating wound healing is of great interest. In this review, we initially discuss polylysine properties, and then focus on the most recent advances in polylysine-containing hydrogels (since 2016) prepared using various chemical and physical crosslinking methods for hemostasis and wound healing applications. Finally, the challenges and future directions in the engineering of these antibacterial hydrogels for wound healing are discussed.

Dual Drug Delivery for Augmenting Bacterial Wound Complications via Tailored Ultradeformable Carriers

Addressing the complex challenge of healing of bacterially infected wounds, this study explores the potential of lipid nanomaterials, particularly advanced ultradeformable particles (UDPs), to actively influence the wound microenvironment. The research introduces a novel therapeutic approach utilizing silver sulfadiazine (SSD) coupled with vitamin E (VE) delivered through UDPs (ethosomes/transferosomes/transethosomes). Comparative physicochemical characterization of these nanosized drug carriers reveals the superior stability of transethosomes, boasting a zeta potential of -36.5 mV. This method demonstrates reduced side effects compared to conventional therapies, with almost 90% SSD and 72% VE release achieved in wound pH in a sustained manner. Cytotoxicity assessment shows 60% cell viability even at the highest concentration (175 μg/mL), while hemolysis test demonstrates RBC lysis below 5% at a concentration of 250 μg/mL. Vitamin E-SSD-loaded transethosomes (VSTEs) significantly enhance cellular migration and proliferation, achieving 95% closure within 24 h, underscoring their promising efficacy. The synergistic method effectively reduces bacterial burden, evidenced by an 80% reduction in Escherichia coli and Staphylococcus aureus within the wound microenvironment. This approach offers a promising strategy to address complications associated with skin injuries.

Microbiological Species and Antibiotic Resistance in Diabetic and Nondiabetic Lower Extremity Wounds: A Comparative Cross-Sectional Study

Severe lower extremity wounds have an increased risk of complications and limb loss. The aim of this study was to evaluate and compare the microbiological profile and antibiotic resistance of wounds in diabetic and nondiabetic patients. A cross-sectional comparative study was carried out at a public hospital including 111 patients with moderate to severe wound infections. Tissue samples were collected during a surgical procedure. One hundred and four patients (94%) had positive cultures and 88 (79%) had a Gram-negative microorganism. Among the 185 cultured microorganisms, 133 (72%) were Gram-negative species. Pseudomonas aeruginosa (23 cases) was the most isolated Gram-negative species, and Enterococcus faecalis (26 cases) was the most prevalent Gram-positive species. Among 185 isolated species, 45 (24%) were extended-spectrum beta-lactamase producers, 23 (12%) were carbapenem-resistant, and 5 (3%) were methicillin-resistant Staphylococcus aureus. Findings revealed that there was no significant difference in the microbiological profile and antibiotic resistance among patients with lower extremity wounds whether they were diabetic or nondiabetic.

Clinical use of 0.1% polyhexanide and propylbetaine on acute and hard-to-heal wounds: a literature review

OBJECTIVE

To summarise the findings on the effect of the clinical use of 0.1% polyhexanide-propylbetaine (PHMB/betaine) solution/gel on acute and hard-to-heal (chronic) wound healing.

METHOD

A literature search was conducted in MEDLINE, CINAHL, Embase, Scopus and the CENTRAL Trials Registry of the Cochrane Collaboration. Paired reviewers conducted title and abstract screening and full-text screening to identify experimental, quasi-experimental and observational studies. Study quality and risk of bias were not formally evaluated.

RESULTS

A total of 17 studies met the eligibility criteria. The findings from 12 studies indicated that the use of 0.1% PHMB/betaine solution/gel had: a low risk of contact sensitivity; could help debridement during wound cleansing; aided effective wound bed preparation; reduced wound size, odour and exudate; improved pain control; reduced microbial load; and enhanced wound healing. The results of three studies indicated that both 0.1% PHMB and saline solution were effective in reducing bacterial load, while another showed that adding 0.1% PHMB to tie-over dressings had no effect on reducing bacterial loads in wounds. Another study concluded that disinfection and granulation of pressure ulcers with hydrobalance dressing with 0.3% PHMB was faster and more effective than using 0.1% PHMB/betaine.

CONCLUSION

The findings of this literature review showed that 0.1% PHMB/betaine solution/gel appeared to be useful and safe for wound cleansing, was effective in removing soft debris and slough from the wound bed, and created a wound environment optimal for healing. Although these actions cannot be attributed solely to this treatment modality, these results do highlight the unique action of this combined product. However, more robust studies are needed to confirm these results.

Molecular evidence sterile tissue damage during pathogenesis of pododermatitis aseptica hemorrhagica circumscripta is associated with disturbed epidermal-dermal homeostasis

Podermatitis aseptica hemorrhagica circumscripta is associated with metalloproteinase 2 weakening of distal phalangeal suspensory structures and sinkage of the distal phalanx in the claw capsule. Pressure from the tuberculum flexorium on the sole epidermis and dermis produces hemorrhagic tissue injury and defective horn production appearing as yellow-red, softened claw horn in region 4 of the sole. A model of the MAPK/ERK signal cascade orchestrating epidermal-dermal homeostasis was employed to determine if sterile inflammatory responses are linked to disturbed signal transduction for epidermal homeostasis in sole epidermis and dermis. The objective was to assess shifts in target genes of inflammation, up- and downstream MAPK/ERK signal elements, and targeted genes supporting epidermal proliferation and differentiation. Sole epidermis and dermis was removed from lateral claws bearing lesions of podermatitis aseptica hemorrhagica circumscripta, medial claws from the same limb and lateral claws from completely normal limbs of multiparous, lactating Holstein cows. The abundance levels of targeted transcripts were evaluated by real-time QPCR. Lesion effects were assessed by ANOVA, and mean comparisons were performed with t-tests to assess variations between mean expression in ulcer-bearing or medial claw dermis and epidermis and completely normal lateral claw dermis and epidermis or between ulcer-bearing dermis and epidermis and medial claw dermis and epidermis. The lesions were sterile and showed losses across multiple growth factors, their receptors, several downstream AP1 transcription components, CMYC, multiple cell cycle and terminal differentiation elements conducted by MAPK/ERK signals and β 4, α 6 and collagen 17A hemidesmosome components. These losses coincided with increased cytokeratin 6, β 1 integrin, proinflammatory metalloproteinases 2 and 9, IL1B and physiologic inhibitors of IL1B, the decoy receptor and receptor antagonist. Medial claw epidermis and dermis from limbs with lateral claws bearing podermatitis aseptica hemorrhagica circumscripta showed reductions in upstream MAPK/ERK signal elements and downstream targets that paralleled those in hemorrhagic lesions. Inhibitors of IL1B increased in the absence of real increases in inflammatory targets in the medial claw dermis and epidermis. Losses across multiple signal path elements and downstream targets were associated with negative effects on targeted transcripts supporting claw horn production and wound repair across lesion-bearing lateral claws and lesion-free medial claw dermis and epidermis. It was unclear if the sterile inflammation was causative or a consequence of these perturbations.

Growth factors and growth factor gene therapies for treating chronic wounds

Chronic wounds are an unmet clinical need affecting millions of patients globally, and current standards of care fail to consistently promote complete wound closure and prevent recurrence. Disruptions in growth factor signaling, a hallmark of chronic wounds, have led researchers to pursue growth factor therapies as potential supplements to standards of care. Initial studies delivering growth factors in protein form showed promise, with a few formulations reaching clinical trials and one obtaining clinical approval. However, protein-form growth factors are limited by instability and off-target effects. Gene therapy offers an alternative approach to deliver growth factors to the chronic wound environment, but safety concerns surrounding gene therapy as well as efficacy challenges in the gene delivery process have prevented clinical translation. Current growth factor delivery and gene therapy approaches have primarily used single growth factor formulations, but recent efforts have aimed to develop multi-growth factor approaches that are better suited to address growth factor insufficiencies in the chronic wound environment, and these strategies have demonstrated improved efficacy in preclinical studies. This review provides an overview of chronic wound healing, emphasizing the need and potential for growth factor therapies. It includes a summary of current standards of care, recent advances in growth factor, cell-based, and gene therapy approaches, and future perspectives for multi-growth factor therapeutics.