The Basic Science of Wound Healing

Interleukin-33 induces angiogenesis after myocardial infarction via AKT/eNOS signaling pathway

Myocardial infarction (MI) is one of the leading causes of mortality and morbidity worldwide. MI-damaged vascular structures are difficult to completely restore due to the heart's low regenerative capacity. Given interleukin-33 (IL-33) as a potent endothelial activator promoting angiogenesis, this study investigated the role of IL-33 in angiogenesis and cardiac repair after MI. A mouse model of MI was established. IL-33 improved cardiac function and induced an increase in vascular density after MI. Besides, IL-33 promoted human endothelial cells proliferation, migration, and differentiation under both normoxic and hypoxic conditions, consistently with increased angiogenesis in vivo. Mechanistic studies demonstrated that IL-33 could promote angiogenesis by activating eNOS and AKT, and stimulating NO production in vivo and in vitro. Given that injection of exogenous IL-33 induced an inflammatory response, we employed a multifunctional biomimetic nanoparticle drug delivery system to deliver IL-33, thereby enhancing its targeting to the heart for fibrotic therapy and reducing inflammation. In conclusion, our results indicate that IL-33 promotes endothelial angiogenesis after MI through AKT/eNOS/NO signaling pathway. PM&EM/IL-33 nanoparticles may hold promising therapeutic potential for protecting cardiac ischemic injury and mitigating inflammation.

A response surface methodology study on the development of pH-sensitive wound dressings using Rhodamine B-loaded chitosan nanoparticles and sodium alginate-based films

Purpose

This study aimed to develop an innovative, intelligent wound dressing capable of signaling infections through color changes.

Design/methodology/approach

Using response surface methodology, the Rhodamine B fluorescence colorant was encapsulated within colloidal nanoparticles and integrated into a sodium alginate patch at various concentrations. The physical and chemical characteristics of the nanoparticles and the wound dressing were thoroughly analyzed via dynamic light scattering (DLS), zeta potential measurements, scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). Additionally, the biodegradability, hydrophilicity, swelling behavior, release kinetics, porosity, mechanical properties, biocompatibility, and infection detection capability of the wound dressing were evaluated.

Findings

The results indicated that the average diameter of the synthesized colloidal nanoparticles was 300 nm before loading with Rhodamine B and increased to 400 nm after loading, with zeta potentials of 52 mV and -6 mV, respectively. The Rhodamine B-loaded wound dressing demonstrated adequate levels of swelling and hydrophilicity. Release studies revealed the gradual release of Rhodamine B at low pH. Cytotoxicity assays confirmed the high biocompatibility of the engineered wound dressing with the L929 cell line. Furthermore, bacterial exposure experiments indicated that the color change was activated in the presence of infection, making it visible under UV-A light.

Originality/value

This research presents a novel approach to wound care by developing a smart wound dressing that can detect infections via color changes. These findings underscore the potential of this innovative wound dressing to improve infection management in clinical settings through its responsive and biocompatible design.

The promoting effect of Balanus albicostatus cement protein 19k (Balcp19k) on wound healing by regulating fibroblast migration and relieving early-stage inflammation responses

The high incidence of skin wounds (e.g., burns, diabetic ulcers, venous ulcers, pressure sores, and radiation injuries) remains a significant challenge in clinical settings. Dressing materials, infused with bioactive components, are essential and extensively utilized in specific circumstances. According to traditional Chinese medicine therapeutic regimens, powders made of the flesh/shells of Balanus albicostatus were used to treat sores due to their ability to alleviate inflammatory responses. Nevertheless, information is scarce regarding the effective components and the pharmacological mechanisms involved. In this work, purified Balanus albicostatus cement protein 19k (Balcp19k) was obtained as a single-component material via an E. coli-based heterologous expression system. It had the potential to promote fibroblast proliferation and migration, which were crucial for wound healing. Immunofluorescence revealed that Balcp19k treatment promoted M2 macrophage transformation in wound tissues. Correspondingly, the expression of inflammation-related genes (e.g., IL-6, TNF-α, and IFN-γ) was significantly reduced (p < 0.05). Moreover, histological examination indicated that this treatment accelerated skin-wound healing by promoting collagen fiber deposition and angiogenesis, and restraining inflammatory cell infiltration in the full-thickness skin of mice. In conclusion, Balcp19k is a biocompatible, effective constituent found in Balanus albicostatus. This bioactive protein could be novel therapeutic material for wound healing, with ability to regulate fibroblast migration, alleviate early-stage inflammatory responses, and enhance collagen fiber deposition and angiogenesis.

Pharmacological effects of triamcinolone associated with surgical glue on cutaneous wound healing in rats

PURPOSE

The surgical glue is widely used in closing cutaneous surgical wounds. Corticosteroids are indicated for their anti-inflammatory and immunomodulatory properties. The present work evaluated the pharmacological effects of triamcinolone (AT) incorporated into surgical glue (C) on the initial phase of the wound healing process in Wistar rats.

METHODS

Through in-vivo studies, the effects of the healing process, C or C+AT in the same rat were evaluated for seven and 14 days post-surgery.

RESULTS

The C+AT association did not change the physicochemical properties of the polymer. This association in wound healing confirmed the anti-inflammatory and immunomodulatory effects of the corticosteroid, with less neovascularization and fibrosis, in addition to the remodeling of the extracellular matrix carried out by the balance of myofibroblasts and less dense collagen fibers, culminating in tissue regeneration and possible reduction of side effects.

CONCLUSION

This association is a powerful and innovative pharmacological tool, promising in translational medicine.

Is there a place for natural agents with anti-inflammatory and antioxidative properties in critically ill patients? Potential usefulness of Xanthohumol

Multi-organ dysfunction is a major issue in critically ill patients, where a significant inflammatory response appears to be the primary factor driving the degree of organ impairment, which correlates with the extent of organ injury. The management of inflammation requires a multidisciplinary approach, including antibiotics for infection control, circulatory and respiratory support, and correction of coagulation abnormalities. However, the use of anti-inflammatory treatments is typically restricted to a selected group of medications, with their effectiveness remaining the subject of extensive debate. Xanthohumol (Xn), a natural compound extracted from hops, possesses strong anti-inflammatory and antioxidative properties, with a mild anti-coagulation effect. Its biological activity is related to the inhibition of different inflammatory pathways, reduction in cytokine production and secretion, and an increase in antioxidative enzyme activity. This review examined the potential use of Xn as an adjuvant in the treatment of various pathologies in critically ill patients.

Smart drug delivery and responsive microneedles for wound healing

Wound healing is an ongoing concern for the medical community. The limitations of traditional dressings are being addressed by materials and manufacturing technology. Microneedles (MNs) are a novel type of drug delivery system that has been widely used in cancer therapy, dermatological treatment, and insulin and vaccine delivery. MNs locally penetrate necrotic tissue, eschar, biofilm and epidermis into deep tissues, avoiding the possibility of drug dilution and degradation and greatly improving administration efficiency with less pain. MNs represent a new direction for wound treatment and transdermal delivery. In this study, we summarise the skin wound healing process and the mechanical stimulation of MNs in the context of the wound healing process. We also introduce the structural design and manufacture of MNs. Subsequently, MNs are categorised according to the loaded drugs, where the design of the MNs according to the traumatic biological/biochemical microenvironment (pH, glucose, and bacteria) and the physical microenvironment (temperature, light, and ultrasound) is emphasised. Finally, the advantages of MNs are compared with traditional drug delivery systems and their prospects are discussed.

The Effect of Topical Cow's Milk on the Healing of Diabetic Foot Ulcers: A Randomized Controlled Pilot Clinical Trial

Diabetic foot ulcer (DFU) is a very serious side effect among the diabetic patients with substantial clinical and economic consequences. The aim of this study was to investigate the efficacy of cows' milk topical ointment, as an available and cost-effective natural product, on accelerating the healing of DFU. In this randomized controlled clinical trial, patients with grade 1 or 2 DFU were randomly divided into two groups of intervention (n = 50) and control (n = 49). For patients of intervention group, cows' milk 20% topical ointment was applied on the ulcer once daily for two weeks, while a type of novel dressing was used for control group with the same frequency and duration. Both groups received usual standard wound care measures. The percentage of change in the ulcer size and the number of cases with complete wound healing (>90% reduction in the ulcer size) were recorded in the both groups. The ulcer size significantly reduced in both groups on the seventh and 14th days of intervention; however, the percentage of reduction was significantly higher in the intervention (milk) group compared to control at both time points (44.64 ± 15.98 vs. 24.95 ± 12.78, P < .001; 67.67 ± 22.15 vs. 42.87 ± 19.74, P < .001). Furthermore, although more patients in the intervention group (n = 4, 8%) showed complete healing of the ulcer compared to control (n = 0), the difference was not statistically significant (P = .117). Cow's milk 20% topical ointment improves and accelerates the healing of diabetic foot ulcers. However, more clinical studies are required to confirm these effects.

Advances in proteins, polysaccharides, and composite biomaterials for enhanced wound healing via microenvironment management: A review

Wound management is crucial yet imposes substantial social and economic burdens on patients and healthcare systems. The recent rapid advancements in biomaterials and manufacturing technology have created favorable conditions for expediting wound healing. This review examines the latest developments in biomacromolecule-based wound dressings, with a particular focus on proteins and polysaccharides, and their role in modulating the wound microenvironment. The importance of extracellular matrix (ECM)-inspired materials, such as hydrogels and biomimetic dressings, is emphasized. Additionally, this review explores the functionalization of wound dressings, emphasizing properties such as hemostatic capabilities, pain relief, antimicrobial activity, and innovative smart functions like electroceuticals and wound condition monitoring. The study integrates discussions on both the macroscopic healing outcomes and the microscopic pathophysiological mechanisms, highlighting recent advances in managing wound environments to expedite healing. Finally, the review critically assesses the challenges associated with the clinical translation of these wound-healing materials in the future.

Transdermal characteristic study of bovine sialoglycoproteins with anti-skin aging and accelerating skin wound healing

BACKGROUND

Sialoglycoproteins play important roles in various biological processes, including cell adhesion, immune response, and cell signaling. Our previous studies indicated that the bovine sialoglycoproteins could be developed as a reagent against skin aging and as a new candidate for accelerating skin wound healing as well as inhibiting scar formation. However, transdermal characteristic of the bovine sialoglycoproteins is still unknown.

AIMS

This study investigated the transdermal permeation of the bovine sialoglycoproteins through porcine skin using the Franz diffusion cell method.

RESULTS

Our study showed that the bovine sialoglycoproteins could penetrate through the porcine skin with a linear permeation pattern described by the regression equation N% = 11.49 t-3.858, with a high coefficient of determination (R2 = 0.9903). The histochemical results demonstrated the widespread distribution of the bovine sialoglycoproteins between the epidermal and dermal layers, which suggesting parts of the bovine sialoglycoproteins had ability to traverse the epidermal barrier. The results of the lectin microarrays indicated highly enriched glycopatterns on the bovine sialoglycoproteins, which also appeared in permeated porcine skin. The LC-MS/MS analysis further showed that the bovine sialoglycoproteins were composed of approximately 100 proteins with molecular weight ranging from 748.4 kDa to 10 kDa, and there were 23 specific bovine sialoglycoproteins with molecular weight ranging from 69.2 kDa to 10 kDa to be characterized in permeated porcine skin.

CONCLUSIONS

Parts of the bovine sialoglycoproteins with molecular weight less than 69.2 kDa had ability to traverse the epidermal barrier. Understanding the permeation characteristics of the bovine sialoglycoproteins for developing innovative formulations with therapeutic benefits, contributing to advancements in cosmetic and dermatological fields.

Recombinant human amelogenin promotes wound healing by enhancing angiogenesis

The first barrier of the human body is the skin, and more serious harm may occur when skin wound healing is delayed. One of the components of enamel matrix proteins is amelogenin, which inhibits inflammation and promotes periodontal tissue regeneration. However, its role in skin wound healing and angiogenesis is inconclusive. Thus, this study aimed to assess the therapeutic effect of recombinant human amelogenin (rhAM) on mouse skin wounds and to determine its effect on angiogenesis and its underlying mechanism. rhAM was expressed in Escherichia coli and purified using the optimized acetic acid method. A skin injury mouse model was established to explore the effects of rhAM on skin wound healing. After treatment with rhAM for 7 days, the wound healing rate was calculated, and the therapeutic effect of rhAM on skin wounds was assessed using hematoxylin & eosin (HE), Masson, and CD31 immunofluorescence staining. The expression of growth and inflammatory factors in wound tissues were detected using Western Blot. In addition, the rhAM effects on the proliferation and migration of human umbilical vein endothelial cells (HUVEC) and mouse fibroblasts (NIH 3T3) were studied in vitro using the Cell Counting Kit-8, cell scratch, cytoskeleton staining, and qPCR. The rhAM effect on HUVEC angiogenesis and its potential mechanism was studied using tube formation and Western Blot. The results showed that the purity of the obtained rhAM was more than 90 % using the optimized acetic acid method, and high-dose rhAM treatment could improve wound healing rate in mice. Additionally, more blood vessels and collagen were produced in the skin wound, and the expression of angiopoietin-related protein 2 (ANGPTL2) and transforming growth factor (TGF)-β1 was upregulated; however, that of interleukin-6 was down-regulated. We also found that rhAM promoted the proliferation and migration of HUVEC and NIH 3T3, the mRNA levels of vascular endothelial growth factor (VEGF), fibroblast growth factor, TGF-β1 and ANGPTL2 in HUVEC cells were upregulated, and expression of VEGF and phosphorylation of the p38 mitogen-activated protein kinase were activated. Therefore, rhAM could promote skin wound healing by upregulating angiogenesis and inhibiting inflammation.

Emerging Frontiers in In Situ Forming Hydrogels for Enhanced Hemostasis and Accelerated Wound Healing

With a surge in the number of accidents and chronic wounds worldwide, there is a growing need for advanced hemostatic and wound care solutions. In this regard, in situ forming hydrogels have emerged as a revolutionary biomaterial due to their inherent properties, which include biocompatibility, biodegradability, porosity, and extracellular matrix (ECM)-like mechanical strength, that render them ideal for biomedical applications. This review demonstrates the advancements of in situ forming hydrogels, tracing their evolution from injectable to more sophisticated forms, such as sprayable and 3-D printed hydrogels. These hydrogels are designed to modulate the pathophysiology of wounds, enhancing hemostasis and facilitating wound repair. The review presents different methodologies for in situ forming hydrogel synthesis, spanning a spectrum of physical and chemical cross-linking techniques. Furthermore, it showcases the adaptability of hydrogels to the dynamic requirements of wound healing processes. Through a detailed discussion, this article sheds light on the multifunctional capabilities of these hydrogels such as their antibacterial, anti-inflammatory, and antioxidant properties. This review aims to inform and inspire continued advancement in the field, ultimately contributing to the development of sophisticated wound care solutions that meet the complexity of clinical needs.

3D printing of bacterial cellulose for potential wound healing applications: Current trends and prospects

Several advances in skin tissue engineering have been made to restore skin damage, facilitating wound healing. Bacterial cellulose (BC), a naturally occurring polymer, has gained attention as a potential material in wound healing due to its unique physical and biological properties. In recent years, with the advent of 3D bio-printing technology, new avenues have opened for fabricating customized wound dressings and scaffolds for tissue engineering purposes. The existing literature in this field mainly focuses on the ways of modifications of bacterial cellulose to make it printable. Still, the applicability of 3D printed scaffolds for wound healing needs to be explored more. This review article focuses on the current research on using 3D-printed BC for skin regeneration, including its production methods and physical and biological properties, making it a better choice than traditional dressings. Furthermore, it also highlights the limitations and future directions for using BC in wound healing and tissue engineering applications. This review provides a comprehensive and up-to-date exploration of the applications of 3D-printed BC in wound healing, drawing insights from pre-existing studies and emphasizing patient compliance, clinical outcomes, and economic viability.

Postoperative Wound Care in Dermatologic Surgery: Update And Narrative Review

Dermatologic surgery is associated with a very low risk of complications. There is no widely accepted, evidence-based protocol with recommendations for postoperative wound care after dermatologic surgery. In this narrative review, we will be discussing the evidence on surgical wound care products and procedures. Overall, we found relatively few studies and, in many cases, a lack of statistically significant differences, possibly because of the low rate of complications. We'll be discussing the evidence on when we should initiate wound care procedures and their frequency, the type of ointment and antiseptics that should be applied, and the type of dressings that should be used. Despite the very few studies available on postoperative wound care following dermatologic surgery, there is sufficient evidence as to not recommend the use of prophylactic topical antibiotics. We also analyze the currently available evidence on surgical wound care in special situations, such as management of skin grafts, partial skin graft donor sites, xenografts/biomembranes, and surgical wounds to the legs.

Clinically Applied Biomechanics of Mesh-reinforced Ventral Hernia Repair: A Practical Review

Background

Ventral hernia repair is inherently prone to recurrence. This article is a practical review that summarizes the literature on the biomechanics of ventral hernia repairs to provide clinically applicable, evidence-based recommendations to reduce hernia recurrence.

Methods

A practical review of all relevant literature in PubMed concerning the mechanics of ventral hernia repairs and the forces involved was conducted in August 2023.

Results

Of the 598 full-text publications retrieved, 29 satisfied inclusion criteria. Among these, 5 articles included enough numeric data for a quantitative analysis of the ultimate tensile strength of the layers of the abdominal wall.

Conclusions

The utilization of mesh in ventral hernia repairs is recommended to strengthen weakened abdominal wall tissue. It is essential to primarily close the anterior sheath with a robust mesh-tissue overlap to promote "load-sharing" between the mesh and the abdominal wall. This approach reduces mesh deformity and stress on fixation points, leading to lower hernia recurrence rates. Minimizing mesh fixation (when placed in the retromuscular plane) can reduce postoperative pain and hospital stay without significantly affecting hernia recurrence. Orienting mesh according to abdominal anisotropy is crucial for reducing mesh stiffness, improving healing, and preventing recurrence. Future studies with advanced computer modeling will continue to provide further insights into mesh biomechanics and abdominal wall healing.

[Translated article] Postoperative Wound Care in Dermatologic Surgery: Update And Narrative Review

Dermatologic surgery is associated with a very low risk of complications. There is no widely accepted, evidence-based protocol with recommendations for postoperative wound care after dermatologic surgery. In this narrative review, we will be discussing the evidence on surgical wound care products and procedures. Overall, we found relatively few studies and, in many cases, a lack of statistically significant differences, possibly because of the low rate of complications. We'll be discussing the evidence on when we should initiate wound care procedures and their frequency, the type of ointment and antiseptics that should be applied, and the type of dressings that should be used. Despite the very few studies available on postoperative wound care following dermatologic surgery, there is sufficient evidence as to not recommend the use of prophylactic topical antibiotics. We also analyze the currently available evidence on surgical wound care in special situations, such as management of skin grafts, partial skin graft donor sites, xenografts/biomembranes, and surgical wounds to the legs.

A comparative study of the established methods and evaluation of rat trauma models

BACKGROUND

Scientific animal models are indispensable for studying trauma repair. This work aimed at establishing a more scientific rat trauma model by studying different rat trauma models caused by different trauma numbers, locations, and trauma attachment tension unloaders and rat age.

METHODS

A four-trauma self-upper, lower, left and right control model; a two-trauma self-trauma bare and ring control model; and a young and old rat trauma model were created to evaluate the condition of these traumas.

RESULTS

In the four-trauma self-control model, the healing status of the upper proximal cephalic trauma was better than that of the lower proximal caudal trauma, whereas there was no significant difference between the left and right trauma. The healing rate and postwound condition of the trauma with a ring control in the two-trauma model were better than those of the bare side. The healing speed of the old rats was slower, and the amount of extracellular matrix in the subcutaneous tissue after healing was significantly lower than that of the young rats.

CONCLUSION

The double trauma with a ring is a more scientific and reasonable experimental model. There is a significant difference between young and old rats in the wound healing process. Therefore, the appropriate age of the rats should be selected according to the main age range of the patients with similar conditions in the clinical setting being mimicked.

Exploring nanobioceramics in wound healing as effective and economical alternatives

Wound healing is a sophisticated process for which various treatment methods have been developed. Bioceramics with the ability to release inorganic ions in biological environments play a crucial role in cellular metabolism and exhibit bactericidal activity, contributing to numerous physiological processes. Their multifaceted roles in biological systems highlight their significance. The release of different metallic ions from bioceramics enables the repair of both hard and soft tissues. These ions may be effective in cell motility, proliferation, differentiation, adhesion, angiogenesis, and antibiosis. Unlike conventional medications, the bioactivity and antibacterial properties of bioceramics are typically not associated with side effects or bacterial resistance. Bioceramics are commonly recognized for their capcity to facilitate the healing of hard tissues due to their exceptional mechanical properties. In this review, we first explore wound treatment and its prevalent methods, and subsequently, we discuss the application of three primary categories of bioceramics-oxide ceramics, silicate-based ceramics, and calcium-phosphate ceramics-in the context of wound treatment. This review introduces bioceramics as a cost-effective and efficient alternative for wound repair. Our aim is to inspire researchers to incorporate bioceramics with other biomaterials to achieve enhanced, economical, expedited, and safer wound healing.

A mathematical model for wound healing in the reef-building coral Pocillopora damicornis

Coral reefs, among the most diverse ecosystems on Earth, currently face major threats from pollution, unsustainable fishing practices , and perturbations in environmental parameters brought on by climate change. Corals also sustain regular wounding from other sea life and human activity. Recent reef restoration practices have even involved intentional wounding by systematically breaking coral fragments and relocating them to revitalize damaged reefs, a practice known as microfragmentation. Despite its importance, very little research has explored the inner mechanisms of wound healing in corals. Some reef-building corals have been observed to initiate an immunological response to wounding similar to that observed in mammalian species. Utilizing prior models of wound healing in mammalian species as the mathematical basis, we formulated a mechanistic model of wound healing, including observations of the immune response and tissue repair in scleractinian corals for the species Pocillopora damicornis. The model consists of four differential equations which track changes in remaining wound debris, number of cells involved in inflammation, number of cells involved in proliferation, and amount of wound closure through re-epithelialization. The model is fit to experimental wound size data from linear and circular shaped wounds on a live coral fragment. Mathematical methods, including numerical simulations and local sensitivity analysis, were used to analyze the resulting model. The parameter space was also explored to investigate drivers of other possible wound outcomes. This model serves as a first step in generating mathematical models for wound healing in corals that will not only aid in the understanding of wound healing as a whole, but also help optimize reef restoration practices and predict recovery behavior after major wounding events.

Effect of macrophages combined with supernatant of mesenchymal stem cell culture and macrophage culture on wound healing in rats

Wound healing is an orderly sequence of events restoring the integrity of the damaged tissue. It consists of inflammatory, proliferation, and remodeling phases. The objective of the current study was to investigate the effect of local transplantation of cultured macrophage loaded with mesenchymal stem cell/macrophage culture supernatants on wound healing. Sixty-four healthy adult male Wistar rats were randomized into 4 groups of sixteen animals each: 1) SHAM group. 2) MAC-MSC/SN group: One-milliliter application of a mixture comprising mesenchymal stem cell and macrophage culture supernatants in a 1:1 ratio was administered locally to the wound bed. 3) MAC group: Local transplantation of macrophage cells cultured in the wound bed. 4) MAC + MAC-MSC/SN group: Local transplantation of cultured macrophage in combination with mesenchymal stem cell/ macrophage culture supernatants in the wound bed. An incisional wound model was used for biomechanical studies, while an excisional wound model was used for biochemical, histopathological, and planimetric assessments. The wound area was significantly reduced in the MAC + MAC-MSC/SN group compared to other groups (P < 0.05). Biomechanical measurements from the MAC + MAC-MSC/SN group were significantly higher compared to other experimental groups (P < 0.05). Biochemical and quantitative histopathological analyses revealed a significant difference between MAC + MAC-MSC/SN and other groups (P < 0.05). MAC + MAC-MSC/SN showed the potential to improve wound healing significantly. This appears to work by angiogenesis stimulation, fibroblast proliferation, inflammation reduction, and granulation tissue formation during the initial stages of the healing process. This accelerated healing leads to earlier wound area reduction and enhanced tensile strength of the damaged area due to the reorganization of granulation tissue and collagen fibers.

A Systematic Review on Biochemical Perspectives on Natural Products in Wound Healing: Exploring Phytochemicals in Tissue Repair and Scar Prevention

Wound healing is a critical process in tissue repair following injury, and traditional herbal therapies have long been utilized to facilitate this process. This review delves into the mechanistic understanding of the significant contribution of pharmacologically demonstrated natural products in wound healing. Natural products, often perceived as complex yet safely consumed compared to synthetic chemicals, play a crucial role in enhancing the wound-healing process. Drawing upon a comprehensive search strategy utilizing databases such as PubMed, Scopus, Web of Science, and Google Scholar, this review synthesizes evidence on the role of natural products in wound healing. While the exact pharmacological mechanisms of secondary metabolites in wound healing remain to be fully elucidated, compounds from alkaloids, phenols, terpenes, and other sources are explored here to delineate their specific roles in wound repair. Each phytochemical group exerts distinct actions in tissue repair, with some displaying multifaceted roles in various pathways, potentially enhancing their therapeutic value, supported by reported safety profiles. Additionally, these compounds exhibit promise in the prevention of keloids and scars. Their potential alongside economic feasibility may propel them towards pharmaceutical product development. Several isolated compounds, including chlorogenic acid, thymol, and eugenol from natural sources, are undergoing investigation in clinical trials, with many reaching advanced stages. This review provides mechanistic insights into the significant role of pharmacologically demonstrated natural products in wound healing processes.

Antibacterial properties of photo-crosslinked chitosan/methacrylated hyaluronic acid nanoparticles loaded with bacitracin

The current treatments for wounds often fail to induce adequate healing, leaving wounds vulnerable to persistent infections and development of drug-resistant microbial biofilms. New natural-derived nanoparticles were studied to impair bacteria colonization and hinder the formation of biofilms in wounds. The nanoparticles were fabricated through polyelectrolyte complexation of chitosan (CS, polycation) and hyaluronic acid (HA, polyanion). UV-induced photo-crosslinking was used to enhance the stability of the nanoparticles. To achieve this, HA was methacrylated (HAMA, degree of modification of 20 %). Photo-crosslinked nanoparticles obtained from HAMA and CS had a diameter of 478 nm and a more homogeneous size distribution than nanoparticles assembled solely through complexation (742 nm). The nanoparticles were loaded with the antimicrobial agent bacitracin (BC), resulting in nanoparticles with a diameter of 332 nm. The encapsulation of BC was highly efficient (97 %). The BC-loaded nanoparticles showed significant antibacterial activity against gram-positive bacteria Staphylococcus aureus, Methicillin-resistant S. aureus and S. epidermidis. Photo-crosslinked HAMA/CS nanoparticles loaded with BC demonstrated inhibition of biofilm formation and a positive effect on the proliferation of mammalian cells (L929). These crosslinked nanoparticles have potential for the long-term treatment of wounds and controlled antibiotic delivery at the location of a lesion.

Novel Synthesized Benzophenone Thiazole Hybrids Exhibited Ex Vivo and In Silico Anti-Inflammatory Activity

Novel benzophenone-thiazole hybrids with different substituents were synthesized and evaluated for anti-inflammatory activity using an ex vivo human whole-blood assay. All hybrids (3c and 5a-h) showed significant anti-inflammatory activity via prostaglandin E2 (PGE2) release inhibition. Moreover, 5c (82.8% of PGE2 inhibition), 5e (83.1% of PGE2 inhibition), and 5h (82.1% of PGE2 inhibition) were comparable to the reference drugs. Molecular docking revealed potential preferable binding to the active sites of cyclooxygenase 2 (COX-2) and microsomal prostaglandin E synthase-1 (mPGES-1) enzymes. This study provides the first evidence that benzophenone-thiazole hybrids may also dock in mPGES-1, a new attractive anti-inflammatory drug target, besides providing promising ex vivo anti-inflammatory activity. Thus, the novel hybrids are promising anti-inflammatory lead compounds and highlight the significance of optimal substituent selection in the design of potent PGE2 inhibitors.

Hypothermically Stored Amnion Is Robust and Provides a Scaffold for Supporting Wound Healing by Retaining the Characteristics of Native Tissue

Placental-derived products have been used since the early 1900s for wound applications and have shown clinical utility in supporting wound healing. A hypothermically stored amniotic membrane (HSAM) was developed using a proprietary process to allow for the retention of the extracellular matrix (ECM), viable cells, and key proteins. To evaluate its utility, we characterized the HSAM and compared it to a native unprocessed amniotic membrane (uAM) and a dehydrated amniotic membrane (dAM), as well as assessing the functionality of the HSAM as a scaffold to promote cell growth. The HSAM, uAM, and dAM were compared using scanning electron microscopy (SEM), histology, and thickness. Scaffold durability was assessed in vitro using mechanical testing and a simulated wound fluid (SWF) model. The ability of the HSAM to act as a scaffold was evaluated using an in vitro attachment model. The HSAM showed similar structural characteristics compared to the uAM; however, the dAM was significantly more compact. There were no significant differences between the HSAM and the uAM following degradation in an SWF model. ECM- and placental-related proteins were shared between the HSAM and uAM, and the HSAM enhanced the attachment and proliferation of fibroblasts in vitro. The HSAM is substantially similar to the uAM by retaining key regulatory proteins, resisting degradation in SWF, and acting as a scaffold for cellular growth and invasion.

Wound Healing and Acute Dermal Toxicity Studies of Ludwigia octovalvis (Jacq.) P. H. Raven (Onagraceae) in Sprague-Dawley Rats

Introduction

The aerial part of Ludwigia octovalvis has been used traditionally in some parts of Asia for the management of wounds owing to the presence of phytochemicals such as tannins, flavonoids, and triterpenoids among others. The incidence of wounds, their associated complications, and the cost of wound care are on the increase globally, therefore, the need to develop alternative wound care agents. The aim of this study was to scientifically investigate the wound healing potential of the ethanolic extract of L. octovalvis using the excision wound healing model in rats and also carry out an acute dermal toxicity investigation of the plant extract.

Method

A 70% ethanol extract of L. octovalvis was prepared for the wound healing activity using the excision wound healing model in Sprague-Dawley rats. Aqueous creams (1, 3, and 10%) were prepared and topically applied to the wounds once daily according to the groups of animals. The wounds were assessed for rates of wound closure on days 3, 5, 7, 9, and 11. Re-epithelialization periods were also determined. Sections of wound tissues obtained on day 13 were subjected to histological investigations. An acute dermal toxicity of the plant extract was investigated.

Results

L. octovalvis treatment (1, 3, and 10%) exhibited a mean percentage wound contraction range of 85.36 ± 7.22-94.14 ± 2.23 on day 11. The extract exhibited re-epithelialization periods of 17.3 ± 1.2, 19.8 ± 2.6, and 16.0 ± 1.7 days for the 1, 3, and 10% extract creams, respectively, whereas the cream-only and 1% silver sulfadiazine treatments resulted in a re-epithelialization period of greater than 28 days. Histopathological investigation revealed enhanced fibroblast infiltration and collagen deposition in the treatment groups. No adverse reaction was observed in the acute dermal toxicity study.

Conclusions

Extract of L. octovalvis exhibited wound healing by enhancing wound contraction, re-epithelialization, fibroblast infiltration, and collagen deposition at the wound site. The extract did not exhibit any toxic reaction in the acute dermal toxicity study.

Zein-Coated Zn Metal Particles-Incorporated Nanofibers: A Potent Fibrous Platform for Loading and Release of Zn Ions for Wound Healing Application

Metal particles incorporated into polymer matrices in various forms and geometries are attractive material platforms for promoting wound healing and preventing infections. However, the fate of these metal particles and their degraded products in the tissue environment are still unknown, as both can produce cytotoxic effects and promote unwanted wound reactions. In this study, we develop biodegradable fibrous biomaterials embedded with metal particles that have an immune activation functions. Initially, biodegradable zinc (Zn) nanoparticles were modified with zein (G), a protein derived from corn. The zein-coated zinc particles (Z-G) were then embedded in polycaprolactone (P) fibers at different weight ratios to create fibrous biomaterials via electrospinning, which were subsequently analyzed for potential wound healing applications. We performed multimodal evaluations of the fibrous scaffolds, examining physicochemical properties such as fiber morphology, mechanical strength, hydrophilicity, degradation, and release of zinc ions (Zn2+), as well as biological properties, including in vitro cell culture studies. We provide evidence that the integration of 2.4 wt % of Z-G particles in polycaprolactone (PCL) nanofibrous scaffolds improved its physicochemical and biological functions. The in vitro cellular response of the scaffolds was evaluated using a series of cytotoxicity assays and immunocytochemistry analyses with three different cell types: mouse-derived fibroblast cell lines (NIH/3T3), human dermal fibroblasts (HDFn), and human umbilical vein endothelial cells (HUVECs). The composite fibrous scaffold exhibited robust activation and proliferation of NIH/3T3 and HDFn cells, along with a significant angiogenic potential in HUVECs. Immunocytochemistry confirmed elevated expression of vimentin and α-smooth muscle actin (α-SMA), suggesting that NIH/3T3 and Haden cells were highly differentiated into myofibroblasts. Additionally, the increased expression of CD31 and VE-cadherin in HUVECs suggests that the scaffold supports tube formation, thereby enhancing neovascularization and promoting an effective immune response. Overall, our findings demonstrate the regenerative potential of the self-enhanced Zn hemostatic bioscaffolds, which deliver both Zn2+ ions and zein proteins to nourish cells. This capability not only modulates cellular activities but also contributes to tissue repair and remodeling, making the scaffolds suitable for wound repair and various bioengineering applications.

Cyanoacrylate Adhesives for Cutaneous Wound Closure

Cyanoacrylate-based adhesives are widely used in wound closure, providing good cosmetic results and little discomfort. However, reports in the literature are found about negative effects that include the release of cytotoxic chemicals during biodegradation. In this study, we sought to evaluate and compare the effectiveness of four cyanoacrylate-based adhesives on the closure of skin incisions in Rattus norvegicus. The animals (n = 140) were divided into five groups of 28 animals each according to the wound closure technique: G1 and G2 (n-2-ethyl-cyanoacrylate); G3 (n-2-butyl-cyanoacrylate); G4 (n-2-octyl-cyanoacrylate); and G5 (5 nylon stitches). Midline incisions measuring 5.0 cm in length were created and closed using the different materials evaluated, and on D3, D7, D14, and D21, tensiometric and histopathological analyses were performed. Shorter wound closure and adhesion times were observed in G4 animals. At D3 and D7, G5 presented greater tensiometric resistance in the animals of G5, with a decrease in D14 and D21 compared to the other groups. On the other hand, the wounds of G3 and G4 were more resistant in D14 and D21, reaching maximum resistance values. Polymorphonuclear and mononuclear cells are more prevalent and more granulation tissue was observed in G5. The deposition of type III collagen was more evident in G5, whilst there was no difference in the amount of type I collagen in any of the groups treated with cyanoacrylate adhesives. Larger areas stained positive for VEGF-α in G2 and smaller areas in G4, with peaks at D7 and D14. In general, cyanoacrylate adhesives cause less intense inflammatory reactions, resulting in shorter healing times when compared to nylon sutures.

Advances in Electrospun Nanofiber Membranes for Dermatological Applications: A Review

In recent years, a wide variety of high-performance and versatile nanofiber membranes have been successfully created using different electrospinning methods. As vehicles for medication, they have been receiving more attention because of their exceptional antibacterial characteristics and ability to heal wounds, resulting in improved drug delivery and release. This quality makes them an appealing choice for treating various skin conditions like wounds, fungal infections, skin discoloration disorders, dermatitis, and skin cancer. This article offers comprehensive information on the electrospinning procedure, the categorization of nanofiber membranes, and their use in dermatology. Additionally, it delves into successful case studies, showcasing the utilization of nanofiber membranes in the field of skin diseases to promote their substantial advancement.

Enhancing Patient Outcomes: A Novel Nomogram Prediction Model Based on Systemic Immune-Inflammation Index for Esophageal Stricture After Endoscopic Submucosal Dissection

BACKGROUND

Endoscopic submucosal dissection (ESD) is a widely utilized treatment for early esophageal cancer. However, the rising incidence of postoperative esophageal stricture poses a significant challenge, adversely affecting patients' quality of life and treatment outcomes. Developing precise predictive models is urgently required to enhance treatment outcomes.

MATERIALS AND METHODS

This study retrospectively analyzed clinical data from 124 patients with early esophageal cancer who underwent ESD at Ningbo Medical Center Lihuili Hospital. Patients were followed up to assess esophageal stricture incidence. Binary logistic regression analysis was used to identify factors associated with post-ESD esophageal stricture. A novel nomogram prediction model based on Systemic Immune-inflammation Index (SII) was constructed and evaluated using receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA).

RESULTS

ROC curve analysis showed that the optimal value of SII for predicting esophageal stricture was 312.67. Both univariate and multivariate analyses identified lesion infiltration depth (< M2 vs. ≥ M2, p = 0.002), lesion longitudinal length (< 4 cm vs. ≥ 4 cm, p = 0.008), circumferential resection range (< 0.5, 0.5-0.75, ≥ 0.75, p = 0.014), and SII (< 312.67 vs. ≥ 312.67, p = 0.040) as independent risk factors for post-ESD esophageal stricture. A novel nomogram prediction model incorporating these four risk factors was developed. Validation using ROC curve analysis demonstrated satisfactory model performance, while calibration curves indicated good agreement between model-predicted risk and observed outcomes.

CONCLUSION

We successfully constructed a novel nomogram prediction model based on SII, which can accurately and intuitively predict the occurrence of esophageal stricture after ESD, providing guidance for clinicians and improving treatment outcomes.

In Situ Triggered Self-Contraction Bioactive Microgel Assembly Accelerates Diabetic Skin Wound Healing by Activating Mechanotransduction and Biochemical Pathway

Chronic nonhealing skin wounds, characterized by reduced tissue contractility and inhibited wound cell survival under hyperglycemia and hypoxia, present a significant challenge in diabetic care. Here, an advanced self-contraction bioactive core-shell microgel assembly with robust tissue-adhesion (SMART-EXO) is introduced to expedite diabetic wound healing. The SMART-EXO dressing exhibits strong, reversible adhesion to damaged tissue due to abundant hydrogen and dynamic coordination bonds. Additionally, the core-shell microgel components and dynamic coordination bonds provide moderate rigidity, customizable self-contraction, and an interlinked porous architecture. The triggered in situ self-contraction of the SMART-EXO dressing enables active, tunable wound contraction, activating mechanotransduction in the skin and promoting the optimal fibroblast-to-myofibroblast conversion, collagen synthesis, and angiogenesis. Concurrently, the triggered contraction of SMART-EXO facilitates efficient loading and on-demand release of bioactive exosomes, contributing to re-epithelialization and wound microenvironment regulation in diabetic mice. RNA-seq results reveal the activation of critical signaling pathways associated with mechanosensing and exosome regulation, highlighting the combined biomechanical and biochemical mechanisms. These findings underscore SMART-EXO as a versatile, adaptable solution to the complex challenges of diabetic wound care.

Speech intelligibility prediction based on a physiological model of the human ear and a hierarchical spiking neural network

A speech intelligibility (SI) prediction model is proposed that includes an auditory preprocessing component based on the physiological anatomy and activity of the human ear, a hierarchical spiking neural network, and a decision back-end processing based on correlation analysis. The auditory preprocessing component effectively captures advanced physiological details of the auditory system, such as retrograde traveling waves, longitudinal coupling, and cochlear nonlinearity. The ability of the model to predict data from normal-hearing listeners under various additive noise conditions was considered. The predictions closely matched the experimental test data under all conditions. Furthermore, we developed a lumped mass model of a McGee stainless-steel piston with the middle-ear to study the recovery of individuals with otosclerosis. We show that the proposed SI model accurately simulates the effect of middle-ear intervention on SI. Consequently, the model establishes a model-based relationship between objective measures of human ear damage, like distortion product otoacoustic emissions, and speech perception. Moreover, the SI model can serve as a robust tool for optimizing parameters and for preoperative assessment of artificial stimuli, providing a valuable reference for clinical treatments of conductive hearing loss.

45S5 Bioactive Glass-Ointment Positively Effects on Wound Healing in Rats by Regulating TNFα, Il-10, VEGF, and TGFβ

AIM

This study aimed to investigate the effects of 45S5 bioactive glass-ointment (BG) on cutaneous wound healing in rats at the molecular, biochemical, and histopathological levels.

MATERIALS AND METHODS

Thirty-two rats were divided into four groups (n = 8): Control, Sham, BG, and DEX (Dexpanthenol). While no wound treatment was applied to the CONTROL, a wound model was created in the Sham, and no treatment was applied. A wound model was created for other groups, and BG and DEX were applied locally for 21 days. During the 21-day experiment period, feed and water consumption and weight changes were observed. Wound areas were calculated on days 0, 3, 7, 4, and 21. Following treatment, the rats were euthanized and tissues from the wound area and blood samples were collected. While the expression levels of tumor necrosis factor-alpha (TNFα), Interleukin 6 (IL6), Interleukin 10 (IL10), transforming growth factor-beta (TGFβ), and vascular endothelial growth factor (VEGF) genes were determined by qPCR, the levels of TNFα, IL6, and IL10 proteins were measured by ELISA.

RESULTS

It was observed that the BG group showed anti-inflammatory activity by suppressing TNFα levels and stimulating IL-10. In addition, it was determined that BG increased fibroblast activity and vascularization.

CONCLUSION

Current findings showed that topical application of BG has anti-inflammatory effects, while also accelerating healing by increasing vascularity and making positive contributions to tissue healing.

Wound closure techniques for spinoplastic surgery: a review of the literature

PURPOSE

The approach to skin closure in spinal surgery is dependent on surgeon preference and experience. Wound complications, including dehiscence and surgical site infection (SSI), are common following spine surgery. The authors reviewed various wound closure techniques employed in spinal surgery.

METHODS

A systematic review was conducted to identify articles comparing wound closure techniques after posterior spinal surgery. Articles that employed experimental or observational cohort study designs and reported rates of SSI, dehiscence, or scarring following spinal surgery were included.

RESULTS

Eight studies examining closure techniques of the skin were identified: five retrospective cohort studies and three randomized-controlled trials. No differences in the incidence of SSI were reported based on suture technique, although staples were associated with higher SSI rates in single level spinal fusion, and barbed suture resulted in decreased wound complications. The use of intracutaneous sutures was associated with a higher incidence of wound dehiscence when compared to tension-relieving far-near near-far suture (FNS) and far-near near-far interrupted point (FNP) sutures. However, the latter two also resulted in the highest rates of delayed wound healing (i.e., time to fully heal). Modified Allgöwer-Donati suture (MADS) resulted in smaller scar area when compared to vertical mattress suture.

CONCLUSION

Significant differences exist in wound healing when comparing suture techniques in spinal surgery. Surgical staples allow for faster closing time, but are also associated with higher wound complications. Intracutaneous sutures appear to have higher rates of dehiscence compared to vertical mattress suture but display faster wound healing. Future studies are necessary to elucidate contributory factors, including local ischemia and changes in tensile forces.

LEVEL OF EVIDENCE

Level IV.

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

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

Outcomes of Sleeve Gastrectomy in Patients With Organ Transplant-Related Immunosuppression

INTRODUCTION

Obesity is frequent among organ transplant recipients, increasing the risk of acute graft rejection and overall morbimortality. Laparoscopic sleeve gastrectomy (LSG) effectively improves graft survival and associated comorbidities. We first compared 30-d outcomes between chronic immunosuppressed (CI) and nonchronic immunosuppressed (non-CI) patients. Then, between organ transplant and non-organ transplant CI patients who underwent LSG.

METHODS

Patients who underwent LSG within the metabolic and bariatric surgery accreditation and quality improvement program 2017-2019 were included. Using 1:1 and 1:4 propensity score matching analysis, the cohorts were matched for 30 characteristics. We then compared 30-d outcomes between CI and non-CI (analysis 1) and between organ transplant and non-organ transplant CI patients who underwent LSG (analysis 2).

RESULTS

A total of 486,576 patients were included. The matched cohorts in analysis 1 (n = 8978) and analysis 2 (n = 1152, n = 371) had similar preoperative characteristics. Propensity score matching in analysis 1 showed that patients in the CI group had significantly higher rates of renal complications (0.4% versus 0.2%, P = 0.006), unplanned intensive care unit admission (1.1% versus 0.7%, P = 0.003), blood transfusions (1.1% versus 0.7%, P = 0.003), readmissions (4.6% versus 3.5%, P < 0.001), reoperations (1.4% versus 1.0%, P = 0.033), interventions (1.3% versus 1.0%, P = 0.026), and postoperative bleeding (0.6% versus 0.4%, P = 0.013). In analysis 2, patients with organ transplant CI had a higher rate of pulmonary complications (1.1% versus 0.3%, P = 0.043), renal complications (2.4% versus 0.2%, P < 0.001), blood transfusions (6.5% versus 1.3%, P < 0.001), and readmissions (10.0% versus 4.6%, P < 0.001).

CONCLUSIONS

Patients with transplant-related CI who underwent LSG have higher 30-d postoperative complication rates compared to nontransplant-related CI patients; however, there were no differences in terms of mortality, intensive care unit admissions, staple line leaks, or bleeding. LSG is safe and feasible in this high-risk population.

Self-Healing Materials for Bioelectronic Devices

Though the history of self-healing materials stretches far back to the mid-20th century, it is only in recent years where such unique classes of materials have begun to find use in bioelectronics-itself a burgeoning area of research. Inspired by the natural ability of biological tissue to self-repair, self-healing materials play a multifaceted role in the context of soft, wireless bioelectronic systems, in that they can not only serve as a protective outer shell or substrate for the internal electronic circuitry-analogous to the mechanical barrier that skin provides for the human body-but also, and most importantly, act as an active sensing safeguard against mechanical damage to preserve device functionality and enhance overall durability. This perspective presents the historical overview, general design principles, recent developments, and future outlook of self-healing materials for bioelectronic devices, which integrates topics in many research disciplines-from materials science and chemistry to electronics and bioengineering-together.

Transmural macrophage migration into an arterial bioresorbable vascular graft promotes inflammatory-mediated response and collagen deposition for vascular remodeling

Macrophages are the primary cell type orchestrating bioresorbable vascular graft (BVG) remodeling and infiltrate from three sources: the adjacent native vessel, circulating blood, and transmural migration from outer surface of the graft. To elucidate the kinetics of macrophage infiltration into the BVG, we fabricated two different bilayer arterial BVGs consisting of a macroporous sponge layer and a microporous electrospun (ES) layer. The Outer ES graft was designed to reduce transmural cell infiltration from the outer surface and the Inner ES graft was designed to reduce cell infiltration from the circulation. These BVGs were implanted in mice as infrarenal abdominal aorta grafts and extracted at 1, 4, and 8 weeks (n = 5, 10, and 10 per group, respectively) for evaluation. Cell migration into BVGs was higher in the Inner ES graft than in the Outer ES graft. For Inner ES grafts, the majority of macrophage largely expressed a pro-inflammatory M1 phenotype but gradually changed to tissue-remodeling M2 macrophages. In contrast, in Outer ES grafts macrophages primarily maintained an M1 phenotype. The luminal surface endothelialized faster in the Inner ES graft; however, the smooth muscle cell layer was thicker in the Outer ES graft. Collagen fibers were more abundant and matured faster in the Inner ES graft than that in the Outer ES graft. In conclusion, compared to macrophages infiltrating from the circulating blood, transmural macrophages from outside promote the acute inflammatory-mediated response for vascular remodeling and subsequent collagen deposition within BVGs. STATEMENT OF SIGNIFICANCE: To elucidate the kinetics of macrophage infiltration into the bioresorbable vascular graft (BVG), two different bilayer arterial BVGs were implanted in mice as infrarenal abdominal aorta grafts. Cell migration into BVGs was higher in the inner electrospun graft which cells mainly infiltrate from outer surface than in the outer electrospun graft which cells mainly infiltrate from the circulating blood. In the inner electrospun grafts, the majority of macrophages changed from the M1 phenotype to the M2 phenotype, however, outer electrospun grafts maintained the M1 phenotype. Collagen fibers matured faster in the Inner electrospun graft. Compared to macrophages infiltrating from the circulating blood, transmural macrophages from outside promote the acute inflammatory-mediated response for vascular remodeling and subsequent collagen deposition within BVGs.

Unraveling and Harnessing the Immune Response at the Cell-Biomaterial Interface for Tissue Engineering Purposes

Biomaterials are defined as "engineered materials" and include a range of natural and synthetic products, designed for their introduction into and interaction with living tissues. Biomaterials are considered prominent tools in regenerative medicine that support the restoration of tissue defects and retain physiologic functionality. Although commonly used in the medical field, these constructs are inherently foreign toward the host and induce an immune response at the material-tissue interface, defined as the foreign body response (FBR). A strong connection between the foreign body response and tissue regeneration is suggested, in which an appropriate amount of immune response and macrophage polarization is necessary to trigger autologous tissue formation. Recent developments in this field have led to the characterization of immunomodulatory traits that optimizes bioactivity, the integration of biomaterials and determines the fate of tissue regeneration. This review addresses a variety of aspects that are involved in steering the inflammatory response, including immune cell interactions, physical characteristics, biochemical cues, and metabolomics. Harnessing the advancing knowledge of the FBR allows for the optimization of biomaterial-based implants, aiming to prevent damage of the implant, improve natural regeneration, and provide the tools for an efficient and successful in vivo implantation.

Prediction of wound healing status following dental extraction using Adapted-University of Connecticut osteonecrosis numerical scale: A retrospective study

Background and Aims

There is a scarcity of evidence concerning the use of a prognostic instrument for predicting normal healing, delayed healing, and medication-related osteonecrosis of the jaw (MRONJ) occurrence following tooth extraction in medically compromised patients. The present study aimed to predict healing outcomes following tooth extraction in medically compromised patients using an Adapted-University of Connecticut osteonecrosis numerical scale (A-UCONNS).

Methods

The digital medical records of medically compromised patients were reviewed, who underwent tooth extraction. The A-UCONNS parameters included the initial pathological condition, dental procedures, comorbidities (smoking habits, type and duration of medication, and type of intervention), and administered antiresorptive (AR) medications. Each parameter was assigned a different weight, and the scores were then accumulated and classified into three categories: minimal risk (less than 10), moderate risk (10-15), and significant risk (16 or more). The patient's healing status was categorized as normal healing, delayed healing, or MRONJ.

Results

A total of 353 male patients (mean age: 67.4 years) were recruited from a pool of 3977 patients, where 12.46% of patients had delayed wound healing, and 18.69% developed MRONJ. The median A-UCONNS scores for MRONJ were higher based on initial pathology, comorbidity, and AR drugs compared to normal or delayed healing. In addition, a significant relationship existed between A-UCONNS and healing outcomes (p < 0.05), with a unit increase in A-UCONNS associated with 1.347 times higher odds of experiencing MRONJ compared to normal healing. In contrast, a low score was linked to an increased likelihood of normal wound healing.

Conclusion

The A-UCONNS could act as a promising tool for predicting wound healing outcomes. It can provide clinicians the ability to pinpoint patients at high risk and allow tailoring of patient-specific strategies for improving healing outcomes following tooth extraction.

Photodynamic therapy mediated by methylene blue-loaded PEG accelerates skin mouse wound healing: an immune response

PURPOSE

Conventional approaches for enhancing wound healing may not always yield satisfactory results. Instead, we test the effectiveness of a newly developed photodynamic therapy (PDT) that uses methylene blue (MB) loaded with polyethylene glycol (PEG) (MB-PEG) hydrogel to accelerate wound healing process in mice.

METHODS

A dorsal skin incision with 6 mm punch which topically subjected to MB-PEG hydrogel and a low-level laser light of red light to assess the regeneration process of wounded skin. A total of 63 adult male CD1 mice divided into normal group (no treatment) and other wound groups received different treatments of laser (650 ± 5 nm and power intensity of 180 mW/cm2), MB-PEG, or PDT (MB-PEG followed by laser). The wound healing parameters were investigated by histological examination of the skin and measuring of proinflammatory cytokines at the early stage (48 h) and a late one on day 21.

RESULTS

at 48 h, the score of tissue granulation, inflammation, and angiogenesis process were markedly improved in wounded groups that received MB + PEG combined with laser compared to the group treated with laser alone. On day 21, a significant improvement of the inflammation was detected in the group treated with MB + PEG plus laser compared to the other groups. At 48 h, the upregulated serum levels of tumor necrosis factor (TNF)-α and interleukin (IL)-1β in the wound group were significantly (P < 0.001) reduced in the group treated with MB + PEG combined with laser.

CONCLUSION

MB-PEG based hydrogel improves and accelerates wound closure in the context of laser compared to either single treatment.

Cerium oxide nanoparticles in wound care: a review of mechanisms and therapeutic applications

Skin wound healing is a complex and tightly regulated process. The frequent occurrence and reoccurrence of acute and chronic wounds cause significant skin damage to patients and impose socioeconomic burdens. Therefore, there is an urgent requirement to promote interdisciplinary development in the fields of material science and medicine to investigate novel mechanisms for wound healing. Cerium oxide nanoparticles (CeO2 NPs) are a type of nanomaterials that possess distinct properties and have broad application prospects. They are recognized for their capabilities in enhancing wound closure, minimizing scarring, mitigating inflammation, and exerting antibacterial effects, which has led to their prominence in wound care research. In this paper, the distinctive physicochemical properties of CeO2 NPs and their most recent synthesis approaches are discussed. It further investigates the therapeutic mechanisms of CeO2 NPs in the process of wound healing. Following that, this review critically examines previous studies focusing on the effects of CeO2 NPs on wound healing. Finally, it suggests the potential application of cerium oxide as an innovative nanomaterial in diverse fields and discusses its prospects for future advancements.

Multifunctional polypeptide-based hydrogel bio-adhesives with pro-healing activities and their working principles

Wound healing is a complex physiological process involving hemostasis, inflammation, proliferation, and tissue remodeling. Therefore, there is an urgent need for suitable wound dressings for effective and systematical wound management. Polypeptide-based hydrogel bio-adhesives offer unique advantages and are ideal candidates. However, comprehensive reviews on polypeptide-based hydrogel bio-adhesives for wound healing are still lacking. In this review, the physiological mechanisms and evaluation parameters of wound healing were first described in detail. Then, the working principles of hydrogel bio-adhesives were summarized. Recent advances made in multifunctional polypeptide-based hydrogel bio-adhesives involving gelatin, silk fibroin, fibrin, keratin, poly-γ-glutamic acid, ɛ-poly-lysine, serum albumin, and elastin with pro-healing activities in wound healing and tissue repair were reviewed. Finally, the current status, challenges, developments, and future trends of polypeptide-based hydrogel bio-adhesives were discussed, hoping that further developments would be stimulated to meet the growing needs of their clinical applications.

Biogenerated Oxygen-Related Environmental Stressed Apoptotic Vesicle Targets Endothelial Cells

The dynamic balance between hypoxia and oxidative stress constitutes the oxygen-related microenvironment in injured tissues. Due to variability, oxygen homeostasis is usually not a therapeutic target for injured tissues. It is found that when administered intravenously, mesenchymal stem cells (MSCs) and in vitro induced apoptotic vesicles (ApoVs) exhibit similar apoptotic markers in the wound microenvironment where hypoxia and oxidative stress co-existed, but MSCs exhibited better effects in promoting angiogenesis and wound healing. The derivation pathway of ApoVs by inducing hypoxia or oxidative stress in MSCs to simulate oxygen homeostasis in injured tissues is improved. Two types of oxygen-related environmental stressed ApoVs are identified that directly target endothelial cells (ECs) for the accurate regulation of vascularization. Compared to normoxic and hypoxic ones, oxidatively stressed ApoVs (Oxi-ApoVs) showed the strongest tube formation capacity. Different oxygen-stressed ApoVs deliver similar miRNAs, which leads to the broad upregulation of EC phosphokinase activity. Finally, local delivery of Oxi-ApoVs-loaded hydrogel microspheres promotes wound healing. Oxi-ApoV-loaded microspheres achieve controlled ApoV release, targeting ECs by reducing the consumption of inflammatory cells and adapting to the proliferative phase of wound healing. Thus, the biogenerated apoptotic vesicles responding to oxygen-related environmental stress can target ECs to promote vascularization.

Injectable and Microporous Microgel-Fiber Granular Hydrogel Loaded with Bioglass and siRNA for Promoting Diabetic Wound Healing

Injectable hydrogels find extensive application in the treatment of diabetic wound healing. However, traditional bulk hydrogels are significantly limited due to their nano-porous structure, which obstructs cell migration and tissue infiltration. Moreover, regulating inflammation and matrix metalloproteinase -9 (MMP-9) expression in diabetic wounds is crucial for enhancing wound healing. This study marks the first instance of introducing an efficient, scalable, and simple method for producing microfiber-gel granules encapsulating bioceramics powders. Utilizing this method, an injectable microporous granular microgel-fiber hydrogel (MFgel) is successfully developed by assembling microgel-fibers made from hyaluronic acid (HA) and sodium alginate (SA) loaded with small interfering RNA (siRNA) and bioglass (BG) particles. Compared to traditional hydrogels (Tgel), MFgel possesses a highly interconnected network with micron-sized pores, demonstrating favorable properties for cell adhesion and penetration in in vitro experiments. Additionally, MFgel exhibits a higher compressive modulus and superior mechanical stability. When implanted subcutaneously in mice, MFgel promotes cellular and tissue infiltration, facilitating cell proliferation. Furthermore, when applied to skin defects in diabetic rats, MFgel not only effectively regulates inflammation and suppresses MMP-9 expression but also enhances angiogenesis and collagen deposition, thereby significantly accelerating diabetic wound healing. Taken together, this hydrogel possesses great potential in diabetic wound healing applications.

The Use of Fast-Acting Insulin Topical Solution on Skin to Promote Surgical Wound Healing in Cats

Wound healing is a complex biological process involving a coordinated sequence of events aimed at restoring tissue integrity and function. Recent advancements in wound care have introduced novel therapies, with topical insulin application emerging as a promising strategy for promoting tissue healing. This study, involving 60 female cats (n = 60) undergoing elective spaying, aimed to evaluate the effects of topical fast-acting insulin on the healing process of surgical wounds. Each surgical suture was divided into two regions: the control zone (Zcr) without insulin application and the study zone (Zst), where insulin was applied topically for 10 min every 24 h over eight consecutive days. Assessment of suture healing was conducted using an adapted scale at two time points post-surgery: T1 (day 2) and T2 (day 8). Statistically significant differences were registered in the final healing scale scores between Zcr and Zst (p < 0.022), as well as for the parameter of regional fluid (p-value = 0.017). Additionally, at T2, all Zst regions exhibited wound closure, whereas Zcr did not, although not in a statistically significant manner. The observed discrepancy at T2 between the Zcr and Zst regions may suggest a potential benefit of utilizing insulin. No side effects resulting from the insulin topical application performed by the tutors were recorded in the Zst suture group. This study represents the first exploration of the benefits of topical insulin application for surgical wound healing in cats.

Uterine Cesarean Scar Tissue-An Immunohistochemical Study

Background and Objectives: Wound healing encompasses a multitude of factors and entails the establishment of interactions among components of the basement membrane. The quantification of particle concentrations can serve as valuable biomarkers for assessing biomechanical muscle properties. The objective of this study was to examine the immunoexpression and immunoconcentration of myometrial collagen type VI, elastin, alpha-smooth muscle actin, and smooth muscle myosin heavy chain, as well as the expression of platelets and clusters of differentiation 31 in the uterine scar following a cesarean section (CS). Materials and Methods: A total of 177 biopsies were procured from a cohort of pregnant women who were healthy, specifically during the surgical procedure of CS. The participants were categorized into seven distinct groups. Group 1 consisted of primiparas, with a total of 52 individuals. The subsequent groups were organized based on the duration of time that had elapsed since their previous CS. The analysis focused on the immunoexpression and immunoconcentration of the particles listed. Results: No significant variations were observed in the myometrial immunoconcentration of collagen type VI, elastin, smooth muscle myosin, and endothelial cell cluster of differentiation 31 among the analyzed groups. The concentration of alpha-smooth muscle actin in the myometrium was found to be significantly higher in patients who underwent CS within a period of less than 2 years since their previous CS, compared to those with a longer interval between procedures. Conclusions: Our findings indicate that the immunoconcentration of uterine myometrial scar collagen type VI, elastin, smooth muscle myosin heavy chain, alpha-smooth muscle actin, and endothelial cell marker cluster of differentiation 31 remains consistent regardless of the duration elapsed since the previous CS. The findings indicate that there are no significant alterations in the biomechanical properties of the uterine muscle beyond a period of 13 months following a CS.

Quality of life following liposuction for lipoedema: a prospective outcome study

BACKGROUND

The study examines, for the first time, the impact on quality of life after liposuction for lipoedema. The influence of aesthetic plastic interventions and their effects on treatment outcomes has been a major focus of our research group over the past 20 years.

METHODS

A total of 35 patients were invited to participate in our prospective study, with 30 responding to both the pre- and postoperative questionnaires. The patients received the questionnaires pre-operatively, and 6 months after the liposuction. Our questionnaire set included a self-developed, indication-specific part, along with standardised and validated questionnaires such as the Questions on Life Satisfaction (FLZM), Patient Health Questionnaire (PHQ-4), Rosenberg Self-Esteem Scale (RSES) and the Freiburg personality inventory-revised (FPI-R).

RESULTS

Our self-developed questionnaire showed that our patients feel more balanced, more attractive and more self-confident after the treatment. The FLZM showed significant improvements in all three modules: the general satisfaction with life, the state of health and the outer appearance (body image). Using the PHQ-4, a significant improvement in the two subscales of anxiety and depression could be determined, as well as a reduction in overall mental stress. In addition, the RSES showed a significant improvement in self-esteem post-operatively. Furthermore, the FPI-R indicated a significant improvement in emotional stability.

CONCLUSIONS

Liposuction improves the quality of life in lipoedema patients. Post-operatively, our patients reported less pain and were more satisfied with their bodies and appearance. The hypothesis that liposuction in lipoedema improves the quality of life as a multidimensional construct could be confirmed.

Fucoidan-coated cotton dressing functionalized with biomolecules capped silver nanoparticles (LB-Ag NPs-FN-OCG) for rapid healing therapy of infected wounds

The colonization of pathogenic microbes poses a significant clinical barrier that hinders the physiological wound-healing process. Addressing this challenge, we developed a novel wound dressing using a modified cotton gauze dressing coated with fucoidan and functionalized with silver nanoparticles (LB-Ag NPs-FN-OCG) for the rapid treatment of infected wounds. Firstly, phytochemical-capped LB-Ag NPs were synthesized and characterized using high performance liquid chromatography (HPLC), transmission electron microscopy (TEM), and zeta potential analysis. Secondly, different concentrations of LB-Ag NPs (0.1%-1%) were functionalized into FN-OCG to identify appropriate concentrations that were non-toxic with superior antibacterial activities. Screening assays, including antibacterial, hemolysis, chick chorioallantoic membrane (CAM) assay, and cytotoxicity assay, revealed that LB-Ag NPs (0.5%)-FN-OCG were non-toxic and demonstrated greater efficiency in inhibiting bacterial pathogens (Escherichia coli, Salmonella enterica, Staphylococcus aureus, and Listeria monocytogenes) and promoting fibroblast cell (NIH3T3) migration. In vivo assays revealed that LB-Ag NPs (0.5%)-FN-OCG treatment exhibited excellent wound healing activity (99.73 ± 0.01%) compared to other treatments by inhibiting bacterial colonization, maintaining the blood parameters, developing granulation tissue, new blood vessels, and collagen deposition. Overall, this study highlights that LB-Ag NPs (0.5%)-FN-OCG serve as a antibacterial wound dressing for infected wound healing applications.

Improved in vitro wound healing in response to a superoxidised solution

OBJECTIVE

This study assessed wound healing in response to a superoxidised solution using an in vitro wound healing model.

METHOD

Prewounded reconstructed full-thickness human skin models were treated with 10µl of either superoxidised solution (Hydrocyn aqua, Bactiguard South East Asia Sdn. Bhd., Malaysia) or Dulbecco's phosphate buffered saline (DPBS) and incubated at 37°C for up to seven days, with additional treatments added every 48 hours. On days 0, 1, 2, 5 and 7, triplicate samples were taken for specific immunostaining against cytokeratin 14 and vimentin. At each timepoint, horizontal and vertical wound diameters were measured to demonstrate wound closure. Maintenance media was taken at the same timepoints for the measurement of secreted proinflammatory cytokines interleukin (IL)-1β, IL-6 and tumour necrosis factor (TNF)-ɑ.

RESULTS

At day 1, the superoxidised solution induced significantly lower diameter measurements compared with baseline data at day 0. Both treatment groups demonstrated significantly lower diameter measurements by day 2 when compared with the baseline; however, the average wound size of samples treated with the superoxidised solution was significantly lower when compared to the DPBS-treated group (p<0.05). No significant difference in expression of any proinflammatory was identified at any timepoint.

CONCLUSION

Application of the superoxidised solution resulted in significantly improved wound closure over the first 48 hours in comparison to DPBS-treatment. Furthermore, application of the superoxidised solution did not induce significant proinflammatory effects, despite the significantly reduced wound diameter.

Technological Interventions Enhancing Curcumin Bioavailability in Wound-Healing Therapeutics

Wound healing has been a challenge in the medical field. Tremendous research has been carried out to expedite wound healing by fabricating various formulations, some of which are now commercially available. However, owing to their natural source, people have been attracted to advanced formulations with herbal components. Among various herbs, curcumin has been the center of attraction from ancient times for its healing properties due to its multiple therapeutic effects, including antioxidant, antimicrobial, anti-inflammatory, anticarcinogenic, neuroprotective, and radioprotective properties. However, curcumin has a low water solubility and rapidly degrades into inactive metabolites, which limits its therapeutic efficacy. Henceforth, a carrier system is needed to carry curcumin, guard it against degradation, and keep its bioavailability and effectiveness. Different formulations with curcumin have been synthesized, and exist in the form of various synthetic and natural materials, including nanoparticles, hydrogels, scaffolds, films, fibers, and nanoemulgels, improving its bioavailability dramatically. This review discusses the advances in different types of curcumin-based formulations used in wound healing in recent times, concentrating on its mechanisms of action and discussing the updates on its application at several stages of the wound healing process. Impact statement Curcumin is a herbal compound extracted from turmeric root and has been used since time immemorial for its health benefits including wound healing. In clinical formulations, curcumin shows low bioavailability, which mainly stems from the way it is delivered in the body. Henceforth, a carrier system is needed to carry curcumin, guard it against degradation, while maintaining its bioavailability and therapeutic efficacy. This review offers an overview of the advanced technological interventions through tissue engineering approaches to efficiently utilize curcumin in different types of wound healing applications.

Complications and influence of cutaneous closure technique on subdermal plexus flaps in 97 dogs (2006-2022)

OBJECTIVE

To determine the incidence and severity of complications for subdermal plexus flaps in dogs and compare the complications when using sutures or staples for cutaneous closure of subdermal plexus flaps.

STUDY DESIGN

Retrospective monocentric study.

SAMPLE POPULATION

Ninety-seven client-owned dogs.

METHODS

Dogs that underwent wound reconstruction using subdermal plexus flaps were retrospectively identified. Type of flap, cutaneous closure technique, complications and level of complication associated with their use were recorded. Follow-up was considered adequate if it was more than 10 days postoperatively or until a complication occurred.

RESULTS

Complications were seen in 52 dogs (53.6%), of which 13/18 (72.2%) of dogs had cutaneous closure with skin staples versus 39/79 (49.3%) with skin sutures. The location of the mass/wound on the head and use of an advancement flap was associated with lower incidence of complications (p < .001; p = .018 respectively). Location of the mass/wound on the proximal pelvic limb was associated with a low level of complications (p = .01) on univariable analysis only. On multivariable analysis, only an increased bodyweight was associated with an increased incidence of complications (p = .029).

CONCLUSIONS

Increased weight may be associated with an increased risk of complications with subdermal plexus flaps. No risk factor was found to be associated with the severity of complications.

CLINICAL SIGNIFICANCE

Overall incidence of complications for subdermal plexus flaps in dogs in this study was 53.6%. The number of dogs included in the study was not sufficient to assess if the skin closure technique affects the incidence of complications.