Wound Bed Research Articles

Chitosan nonwoven fabric composited calcium alginate and adenosine diphosphate as a hemostatic bandage for acute bleeding wounds

Acute bleeding following accidental injury is a leading cause of mortality. However, conventional hemostatic bandages impede wound healing by inducing excessive blood loss, dehydration, and adherence to granulation tissue. Strategies such as incorporating active hemostatic agents and implementing chemical modifications can augment the properties of these bandages. Nevertheless, the presence of remote thrombosis and initiators may pose risks to human health. Here, a hemostatic bandage was developed by physically combined chitosan nonwoven fabric, calcium alginate sponge, and adenosine diphosphate. The presented hemostatic bandage not only exhibits active and passive mechanisms for promoting clotting but also demonstrates excellent mechanical properties, breathability, ease of removal without causing damage to the wound bed or surrounding tissues, as well as maintaining an optimal moist environment conducive to wound healing. In vitro evaluation results indicated that the hemostatic bandage possesses favorable cytocompatibility with low levels of hemolysis. Furthermore, it effectively aggregates various blood cells while activating platelets synergistically to promote both extrinsic and intrinsic coagulation pathways. In an in vivo rat model study involving liver laceration and femoral artery injury scenarios, our developed hemostatic bandage demonstrated rapid clot formation capabilities along with reduced blood loss compared to commercially available fabrics.

Substantiation of tactics of chronic wound bed preparation at various stages of the infectious process on the basis of the analysis of the results of microbiological, clinical and morphological parameters

The chronic wounds (CW) bed preparation requires an integrated approach using wound assessment, microbiological and histological analysis, which will avoid skin graft failure.The aim was to evaluate the possibility of using microbiological and morphological parameters of CW assessment to substantiate the choice of tactics of wound bed preparation to skin grafting (SG).Morphological and microbiological indicators of CW (n = 229) at various stages of the infectious process were analyzed. To prepare CW to SG, the following treatment methods were used: dressings, vacuum therapy (VT), mechanical debridement (MD), and ultrasound debridement (UD).The criteria that determine the possibility of CW preparation “under a bandage” in combination with MD are: the absence of inflammation signs and the normal state of granulations (red-pink color, firm and moist), a negative result of wound swabs, the histological result of Si 1/Si 2 and Sp 1/Sp 2. For CW performed with pathologically altered granulations colonized by potential pathogens and having Sp 3, Si 2/Si 3 criteria, the use of 2 UD procedures is indicated (1st in combination with MD, 2nd before SG), between which VT is applied. Critically colonized wounds showing the signs of Sp 3 in combination with Si 1 or Si 2, from which microorganisms are isolated in an amount of ≤105 CFU/ml and are characterized by persistent properties, are an indication for VT, which is performed between two UD procedures. Clinical infection signs, the presence of bright red friable and bulge granulations in the wound, morphological signs of Si 3/Si 2 and Sp 1/Sp 2 are indications for the use of 2 UD procedures in combination with systemic antibiotic therapy based on wound swab culture results.Microbiological and morphological parameters characterize the CW state at various stages of the infectious process (colonization, critical colonization, infection) and are recommended as criteria for choosing tactics for wound bed prepara tion to SG.

Pleiotropic effects of hyaluronic acid and silver sulfadiazine dressings in the treatment of acute and chronic skin lesions.

Hyaluronic acid (HA) is a natural unbranched polymer that belongs to a group of heteropolysaccharide glycosaminoglycans (GAGs) that are major components of the extracellular matrix (ECM), while silver sulfadiazine exerts antibacterial activity. In this study, we evaluated the efficacy and safety of dressings with hyaluronic acid and silver sulfadiazine in acute and chronic lesions, according to the wound bed preparation and TIME principles. Thirty-two patients with acute and chronic injuries participated in the study. After collecting their personal histories and making a differential diagnosis by evaluating their ankle/arm index, patients with a Winsor Index below 0.8 underwent lower extremity color Doppler echocardiography. The dressing protocol followed the principles of wound bed preparation, identifying the prevailing clinical sign by evaluating the lesion background, margins, and perilesional skin. A product containing low molecular weight hyaluronic acid (200 kDa) and silver sulfadiazine 1% was used for the dressing. In the acute lesion group, the protocol we applied resulted in all injuries being healed. Of the 20 treated wounds in the chronic lesion group, 10 healed at the end of 8 weeks of treatment and 8 saw an improvement with a reduction in the lesion area. Consisting of a combination of hyaluronic acid and silver sulfadiazine, the dressing is widely used in the management of acute and chronic skin wounds. In the present study, the healing rate of acute wounds was 100%; in chronic wounds, healing was reported in 50% of cases while in 40% of the remainder, we found a 40% reduction in the lesion area.

Местное лечение контаминированной кожной раны оригинальной лекарственной комбинацией в сочетании с магнитотерапией в эксперименте

Currently, treatment of contaminated skin wounds aggravated by ischemia of superficial soft tissues is a problem that presents certain difficulties. The search for the new ways of treatment and drugs possessing a multidirectional effect is a relevant problem. In this study, we aimed to explore the peculiarities of wound evolution and the effectiveness of the designed combination of medicines and magnetic therapy in a contaminated skin wound case. For the experiment, we divided male Wistar rats into 3 groups and modeled a contaminated skin wound in each of the animals. In the first group, no treatment was performed, in the second, we used the developed combination (benzalkonium chloride, dexpanthenol, pentoxifylline and carboxymethylcellulose sodium salt, combined with magnetic therapy), in the third — ointment with dioxomethyltetrahydropyrimidine + chloramphenicol and magnetic therapy. Planimetry, acid-base balance registration, measurements of microhemocirculation and local temperature of the wound bed underpinned monitoring assessment of the wounds. At the end of the study, the wound area in the second group was 10.7 and 3.7 (p < ; 0.05 ) times smaller than in the first and third groups, respectively, and healing rate — 2.6 and 1.3 (p < 0.05 ) times faster. The maximum values of microhemocirculation and the lowest pH were registered in the second group. Thus, combination of drugs and magnetotherapy we designed promoted healing of a contaminated skin wound, which allows recommending this treatment method for further study at the preclinical level.

Machine Perfusion Deters Ischemia-Related Derangement of a Rodent Free Flap: Development of a Model

IntroductionMachine perfusion can enable isolated support of composite tissues, such as free flaps. The goal of perfusion in this setting is to preserve tissues prior to transplantation or provide transient support at the wound bed. This study aimed to establish a rodent model of machine perfusion in a fasciocutaneous-free flap to serve as an affordable testbed and determine the potential of the developed support protocol to deter ischemia-related metabolic derangement. MethodsRat epigastric-free flaps were harvested and transferred to a closed circuit that provides circulatory and respiratory support. Whole rat blood was recirculated for 8 h, while adjusting the flow rate to maintain arterial-like perfusion pressures. Blood samples were collected during support. Extracellular tissue lactate and glucose levels were characterized with a microdialysis probe and compared with warm ischemic, cold ischemic, and anastomosed-free flap controls. ResultsMaintenance of physiologic arterial pressures (85-100 mmHg) resulted in average pump flow rates of 360–430 μL/min. Blood-based measurements showed maintained glucose and oxygen consumption throughout machine perfusion. Average normalized lactate to glucose ratio for the perfused flaps was 5-32-fold lower than that for the warm ischemic flap controls during hours 2-8 (P < 0.05). ConclusionsWe developed a rat model of ex vivo machine perfusion of a fasciocutaneous-free flap with maintained stable flow and tissue metabolic activity for 8 h. This model can be used to assess critical elements of support in this setting as well as explore other novel therapies and technologies to improve free tissue transfer.

Materials and Device Designs for Wireless Monitoring of Temperature and Thermal Transport Properties of Wound Beds during Healing.

Chronic wounds represent a major health risk for diabetic patients. Regeneration of such wounds requires regular medical treatments over periods that can extend for several months or more. Schemes for monitoring the healing process can provide important feedback to the patient and caregiver. Although qualitative indicators such as malodor or fever can provide some indirect information, quantitative measurements of the wound bed have the potential to yield important insights. The work presented here introduces materials and engineering designs for a wireless system that captures spatio-temporal temperature and thermal transport information across the wound continuously throughout the healing process. Systematic experimental and computational studies establish the materials aspects and basic capabilities of this technology. In vivo studies reveal that both the temperature and the changes in this quantity offer information on wound status, with indications of initial exothermic reactions and mechanisms of scar tissue formation. Bioresorbable materials serve as the foundations for versions of this device that create possibilities for monitoring on and within the wound site, in a way that bypasses the risks of physical removal.

Effectiveness of stingless bee (Kelulut) honey versus conventional gel dressing in diabetic wound bed preparation: A randomized controlled trial

PurposeKelulut honey contains trehalulose and has high antioxidant content, such as phenolic and flavonoid substances, which can promote wound healing. This study evaluated the effectiveness of Kelulut honey in diabetic wound healing compared to a commercially available conventional gel dressing (Intrasite gel). MethodsA prospective, randomized, single-blinded control trial was performed on eligible diabetic patients with full-thickness cavity wounds. Patients’ demographics, size and site of wounds, and baseline routine blood investigations were recorded. The wounds were dressed every other day with Kelulut honey for the intervention group or gel for the control group. The wound size reduction and granulation tissue formation percentage were calculated every 6 days for 1 month. ResultsSeventy-one patients were randomized. After 30 days of follow-up, 62 participants were available for analysis: 30 from the control group and 32 from the treatment group. The control group had increased granulation tissue at baseline and more wounds on the lower limb and posterior trunk. Both groups showed an increasing mean and median percentage of wound epithelialization and granulation tissue over time, with significantly higher values at every timepoint in the honey group (p < 0.05). However, repeated measures analysis of variance and analysis of covariance revealed no significant interaction effect between the different treatments and time, with F (2.02, 121.28) = 0.88, p = 0.417 and F (1.60, 93.95) = 0.79, p = 0.431, respectively. ConclusionThis study revealed that Kelulut honey was comparable to and as effective as the conventional gel in treating diabetic wounds in terms of promoting epithelialization and granulation tissue formation.

Papain Covalent Immobilization in Bacterial Cellulose Films as a Wound Dressing

Ideally, the dressings used in the clinic have characteristics that help the wound closure process. Among several factors that affect the success of this healing process, there is debridement. It manages the wound bed components and the re-epithelialization process. Still, the property of debridement is not generally associated with dressings. Here, we show a chemically modified bacterial cellulose film conjugated to a proteolytic enzyme, papain, as a dressing with debridement properties. Bacterial cellulose films were reacted with a spacer derived from succinic acid and finally had this enzyme covalently immobilized in its structure by an amide bond. FT-IR and UV–vis showed bands typically of bioconjugated polymer. Enzymatic immobilization was very effective under the conditions applied with high yield (33% w/w), and these remained activated after the coupling reaction. The bacterial cellulose film with the enzyme papain attached to it was also very compatible with fibroblast cells, suggesting that it could be a promising wound dressing material for future research.

Biofilm microenvironment triggered self-enhancing photodynamic immunomodulatory microneedle for diabetic wound therapy

The treatment of diabetic wounds faces enormous challenges due to complex wound environments, such as infected biofilms, excessive inflammation, and impaired angiogenesis. The critical role of the microenvironment in the chronic diabetic wounds has not been addressed for therapeutic development. Herein, we develop a microneedle (MN) bandage functionalized with dopamine-coated hybrid nanoparticles containing selenium and chlorin e6 (SeC@PA), which is capable of the dual-directional regulation of reactive species (RS) generation, including reactive oxygen species (ROS) and reactive nitrogen species (RNS), in response to the wound microenvironment. The SeC@PA MN bandage can disrupt barriers in wound coverings for efficient SeC@PA delivery. SeC@PA not only depletes endogenous glutathione (GSH) to enhance the anti-biofilm effect of RS, but also degrades GSH in biofilms through cascade reactions to generate more lethal RS for biofilm eradication. SeC@PA acts as an RS scavenger in wound beds with low GSH levels, exerting an anti-inflammatory effect. SeC@PA also promotes the M2-phenotype polarization of macrophages, accelerating wound healing. This self-enhanced, catabolic and dynamic therapy, activated by the wound microenvironment, provides an approach for treating chronic wounds.

A Programmable Oxygenation Device Facilitates Oxygen Generation and Replenishment to Promote Wound Healing.

Inadequate oxygenation is one of the chief culprits for delayed wound healing. However, current oxygen therapies, such as hyperbaric oxygen therapy and topical oxygen therapy, face hurdles in providing sustained and long-term oxygenation to reverse wound hypoxia. Furthermore, their efficacy in rejuvenating wound injury is restricted by limited penetration of oxygen in the wound bed. Herein, this study proposes a programmable and portable oxygenation device (named GUFO oxydevice) by ingeniously integrating i) a controllable oxygen generation and unidirectional transmission system (COGT-UTS), and ii) a supramolecular assembled perfluorinated hyperbranched polymer/gelatin (GUF) hydrogel in which the perfluorinated hyperbranched polymer (FHBP) acts as an oxygen reservoir to ensure sustained and convenient oxygen replenishment and thus directly regulate the hypoxic wound microenvironment. Accelerating the wound healing process by GUFO oxydeviceis achieved in both a diabetic rat and an acute porcine wound model without any secondary tissue damages. The present study demonstrates that the GUFO oxydevice holds promise as a practically feasible candidate for wound treatment.

USE OF LOW-INTENSITY LASER RADIATION IN THE COMPLEX TREATMENT OF WOUNDS

Abstract. Increasing the eff ectiveness of treatment of infected wounds is an extremely urgent problem, which, despite signifi cant achievements, is far from a fi nal solution. The development of new methods of local impact on wounds, especially laser irradiation and evaluation of its eff ectiveness, are promising.The aim of the study. To evaluate the eff ectiveness of using low-intensity laser irradiation in the complex treatment of wounds.The object of the study was 10 patients with wounds of the lower extremities. Among the examined were 6 men and 4 women aged from 48 to 83 years. 6 patients had type 2 diabetes; in 4 – CHD, obliterating atherosclerosis of the vessels of the lower extremities. All patients involved in the study signed the appropriate informed consent.The complex treatment of all patients included irradiation of the wound with a low-intensity laser (B-Cure Laser); with a power of 250 mW; wavelength 808 nM; with a pulse frequency of 15 kHz; with a pulse duration of 17 μs with an energy of 3.75 Joule/min; with a spot of radiation 45Ч10 mm, lasting 3 minutes around the perimeter of the wound edges and 1 minute on the wound bed. The wound area was measured using the «IntimoMeasure» program. All patients underwent microbiological and cytological examination of smearsprints from the wound on days 1, 3, 5, 7 and 10.Research results. It has been established that the use of low-intensity laser irradiation of the wound has a positive eff ect on the wound healing process.As early as 2-3 days after the start of treatment, the amount of discharge from the wound signifi cantly decreased, the amount of necrotic tissue decreased, and the demarcation line was clearly defi ned. A decrease in the number of necrotic tissues and microorganisms, an increase in the number of leukocytes, monocytes, macrophages, and plasma cells was noted in the smears.After 4-6 days, signs of granulation formation appeared, the number of lymphocytes, macrophages, and plasma cells increased. The concentration of microorganisms did not exceed 10Ч2-3 CFU/ml. At 7-8 days, most of the wounds were without signs of necrotic tissue, granulation tissue increased intensively, signs of connective tissue formation, epithelization from the edges of the wound appeared.On 9-10 days, most of the wounds were represented by granulation tissue with pronounced proliferation of the epithelium at the edges of the wound. During the fi rst three days, the area of the wound decreased by almost 17 % compared to the initial size, and from the 7th day it did not exceed 60 % of the initial level.Conclusions. 1. Low-intensity laser irradiation of wounds against the background of complex drug therapy is an eff ective method of treatment, promotes rapid cleansing of wounds, intensive development of granulations, accelerates epithelization. 2. Availability, ease of use and absolute safety allow recommending this method for use in complex wound treatment.

Review of the role of biofilms in equine wounds: Clinical indications and treatment strategies

SummaryRecognition of the role that biofilms play in the persistence of wounds and lack of response to therapy in horses is increasing. Prevention of biofilm development in the early stages of wound care involves three primary strategies: wound debridement and cleansing to reduce bacterial counts in the wound bed, appropriate use of advanced wound dressings and implementation of topical antimicrobial agents. Once formed, eradication of biofilms requires elimination to improve the wound environment for contraction and epithelialisation while not further harming the native cells integral to the healing process, which is achieved predominantly through repeated lavage and debridement combined with topical antimicrobial therapy. Pseudomonas, Enterococcus and Staphylococcus bacterial species have been most commonly identified in equine wounds with delayed healing. This review will establish why and how biofilms form, how to recognise clinical indications that biofilms have formed in equine wounds and review current diagnostic options and biofilm‐based wound care strategies to eradicate biofilms. Clinical scenarios for cases in which biofilms developed and were successfully treated will be presented. This review will advance practitioners' understanding of the presence and role of biofilms in equine wounds and provide an updated summary of recommended treatment strategies.

Comparison of the Ventral Approach to the Canine Hip Joint Using Gelpi Retractors and an Elastic O-Ring Wound Retractor.

This study included 10 fresh adult cadavers of large breed dogs (6 males and 4 females). Their weight ranged from 25 to 45 kg (mean ± SD: 33.9 ± 6.2 kg). The breeds represented were crossbreed dogs (n = 5), German shepherds (n = 2), Bernese mountain dogs (n = 1), American Staffordshire terriers (n = 1), and Gordon setters (n = 1). Access to the target area and identification of the femoral head and neck was achieved with two Gelpi retractors inserted orthogonally and with the O-WR in all procedures. In each dog, the approach to the hip joint was made on the left and right sides. There was no significant difference in the area of the surgical wound bed between the two sides using either the Gelpi retractors (-0.52 ± 1.87 cm2; CI 95%: -1.86, 0.81 cm2; p = 0.398) or the O-WR (-0.27 ± 2.34 cm2; CI 95%: -1.94, 1.41 cm2; p = 0.729). The area of the surgical wound bed was 6.28 ± 1.72 cm2 (2.72-9.70 cm2) for the Gelpi retractors and 6.34 ± 1.81 cm2 (4.13-10.77 cm2) for the O-WR, and the difference between the Gelpi retractors and the O-WR was not significant (-0.06 ± 1.72 cm2; CI 95%: -0.86, 0.74 cm2; p = 0.879).

Primary Closure Versus Delayed Primary Closure of Class III and IV Surgical Wounds Following Emergency Laparotomy: A Prospective Comparative Study.

Introduction Emergency surgery has a high risk of complications due to the detrimental effect of perioperative sepsis and the relative lack of preoperative optimization of patients. Despite advances in critical care for the management of sepsis, its prevention is dependent on various patient and surgeon factors. Surgical site infection continues to be a major determinant of morbidity and mortality following emergency abdominal surgery, especially in contaminated or dirty wounds. This study aims to compare two techniques of abdominal wall closure, primary closure with subcutaneous suction drains and delayed primary closure following negative pressure wound therapy, in terms of incidence of surgical site infection and morbidity. Materials and methods The study was a prospective comparative study including 50 patients with an acute surgical abdomen requiring laparotomy. The patients were randomized into two groups, Group A (n=25) who underwent primary closure, and Group B (n=25) who underwent delayed primary closure. In Group B patients, a vacuum-assisted closure device was applied in the subcutaneous space for five days prior to the closure of the skin. Outcomes were compared in terms of the incidence of superficial and deep surgical site infection, its association with diabetes mellitus, and the total duration of hospital stay. A chi-square test and an unpaired t-test were used for the test of significance. Results A total of 50 patients, comparable in age, were included in the study. The overall incidence of surgical site infection was significantly higher in patients of Group A as compared to Group B (p=0.0046). There was a positive correlation between diabetes mellitus and the occurrence of wound infection in both groups with the odds ratio being 2.67 and 2.38 respectively. The incidence of superficial wound infection was significantly higher in Group A when compared to Group B (52% versus 24%; p=0.04). Deep surgical site infection was higher in patients of Group A (20% versus 8%) but was not statistically significant (p=0.22). The average duration of hospital stay was 41.56 ± 6.96 and 37.86 ± 6.68 days for patients who developed complications fromGroups A and B respectively, while it was nearly two and a half times lower in uncomplicated cases of Groups A and B (11.71± 1.70 days and 16.58± 1.06 days respectively). The one-tailed unpaired t-test showed a significant difference in means of hospital stay between patients with and without complications (T: 17.06, critical value: 1.677). Conclusion Delayed primary closure is an effective method of managing contaminated and dirty wounds following emergency laparotomy. Negative pressure wound therapy is one technique for preventing wound bed infection and accelerating wound healing in such cases. By combining the above in emergency surgeries, the incidence of surgical site infection and duration of hospital stay can be significantly reduced.

Sternotomy or Thoracotomy: Which One?

Abstract: Penetrating injuries to the chest present a frequent and challenging problems. Median sternotomy and thoracotomy are two choices to explore any trauma to the chest. We report a 37-year-old man with wound and pain in his left chest due to being stabbed with a knife one hour ago. On physical examination, an open wound measured 5x1.5 cm as high as the third rib parallel to the left parasternal line, the edges of the wound bed were flattened by the periosteum. Laboratory examination showed leukocytosis. FAST showed an important left pleural effusion and pericardial fluid. CTA study showed the presence of air in the anterior mediastinum and the left pleural cavity. In the fifth intercostal space, a left anterolateral thoracotomy was performed and 800 ml of blood was evacuated from the left chest. The left lung was lowered to open the pericardium, which caused a further drop in blood pressure; then, the pericardium was opened and a blood clot (1500 ml) was removed. An epicardial wounds were found on the anterior surface of the right ventricle. The left anterior coronary artery was actively bleeding. The hemorrhagic lesion was stitched with 4.0 polypropylene reinforced with a Teflon strip. The patient recovered uneventfully on the sixth postoperative day. During the 14-month follow-up, the patient was fine and back to work. In conclusion, surgeon must be able to decide the technique of approach in the operating room considering the site of injury and the presence of involving organ. Thoracotomy patient can also receive median sternotomy if the cardiac injuries could not be repaired through thoracotomy. In addition, some patients with median sternotomy also received additional thoracotomy due to their pulmonary injuries. Keywords: penetrating injuries; thoracotomy; sternotomy; cardiac injury

The application of nano-hydrogels and hydrogels in wound dressings.

Wounds and the healing process are one of the main concerns of medical science today. A wound is any loss of integrity, or rupture of the layers of skin (epidermis, dermis, and hypodermis) or subcutaneous tissue caused by physical factors (surgical incision, trauma, pressure, and gunshot wounds) or chemical factors (acid burns). It is observed that soft tissue, muscle, or bone is involved in occurrences of wounds. Lesions and fractures of the skin surface necessitate medical attention, wherein dressings expedite the healing process by establishing a physical barrier between the wound and the external environment, thereby preventing further injury or infection. Hydrogel dressings create a moist environment that facilitates common healing steps, such as granulation hyperplasia, epidermal repair, and removal of excess dead tissue. The limited adhesion of the hydrogel and the hydrated wound bed allows for easy removal of the dressing without secondary damage, thereby significantly reducing the discomfort and risk of infection during dressing changes. These modern, wet dressings foster a moist healing environment by absorbing excess inflammatory secretions and allowing proper passage of steam and air, which expedites the healing process. In this analysis, the utilization of hydrogels as wound dressings is briefly presented.

Graft-Host Interaction and Its Effect on Wound Repair Using Mouse Models.

Autologous skin grafting has been commonly used in clinics for decades to close large wounds, yet the cellular and molecular interactions between the wound bed and the graft that mediates the wound repair are not fully understood. The aim of this study was to better understand the molecular changes in the wound triggered by autologous and synthetic grafting. Defining the wound changes at the molecular level during grafting sets the basis to test other engineered skin grafts by design. In this study, a full-thickness skin graft (SKH-1 hairless) mouse model was established. An autologous full-thickness skin graft (FTSG) or an acellular fully synthetic Biodegradable Temporising Matrix (BTM) was grafted. The wound bed/grafts were analysed at histological, RNA, and protein levels during the inflammation (day 1), proliferation (day 5), and remodelling (day 21) phases of wound repair. The results showed that in this mouse model, similar to others, inflammatory marker levels, including Il-6, Cxcl-1, and Cxcl-5/6, were raised within a day post-wounding. Autologous grafting reduced the expression of these inflammatory markers. This was different from the wounds grafted with synthetic dermal grafts, in which Cxcl-1 and Cxcl-5/6 remained significantly high up to 21 days post-grafting. Autologous skin grafting reduced wound contraction compared to wounds that were left to spontaneously repair. Synthetic grafts contracted significantly more than FTSG by day 21. The observed wound contraction in synthetic grafts was most likely mediated at least partly by myofibroblasts. It is possible that high TGF-β1 levels in days 1-21 were the driving force behind myofibroblast abundance in synthetic grafts, although no evidence of TGF-β1-mediated Connective Tissue Growth Factor (CTGF) upregulation was observed.

Вміст факторів росту та фактора 1α, індукованого гіпоксією, в рановому ложі шкіри щурів із метаболічним синдромом

Minor injuries in healthy people usually heal well, but larger wounds or the presence of various physiological (age) or pathological conditions (metabolic syndrome, obesity, diabetes, and cancer) can impede this process. The aim of our work was to determine the factors that may influence the duration of healing (growth factors and hypoxia-induced factor 1α) in the wound bed of rats with metabolic syndrome. The experiments were conducted on 80 white non-linear laboratory rats, aged 4-5 months, which were divided after birth into 2 groups of 40 animals each (20 males and 20 females). Group I rats were subcutaneously injected with saline at a dose of 8 μg/ ml on days 2, 4, 6, 8, and 10 after birth. Group II rats were administered a sodium glutamate solution at a dose of 4.0 mg/ kg at the same time. At the age of 4 months, animals of both subgroups were modeled with incised wounds . The control animals were rats in each of the groups in which wounds were not modeled. The material for biochemical studies was the skin in the areas of the former wound bed. Rats in the control group had their skin excised at the same sites as those in the experimental groups. The skin was homogenized and the content of growth factors of endothelial and nerve cells (VEGF, NGF, respectively) and hypoxia-inducible factor (HIF-1α) was determined by immuno-enzymatic method. In unoperated male rats with metabolic syndrome, the skin content of VEGF, NGF, and HIF-1a increased compared to control animals without the syndrome. In unoperated females with metabolic syndrome, VEGF levels decreased with a simultaneous increase in NGF and HIF-1α. In the wound bed of animals with metabolic syndrome, after the closure of the wound surface, the content of VEGF and HIF-1α increased, and the content of NGF remained unchanged compared with the values in unoperated rats. The results obtained indicate the involvement of growth factors VEGF and NGF and HIF-1α in prolonging the duration of healing of incised wounds in rats with metabolic syndrome. At the same time, these growth factors and HIF-1α may be involved in the mechanisms of development of some postoperative complications.

Multifunctional natural microneedles based methacrylated Bletilla striata polysaccharide for repairing chronic wounds with bacterial infections

The expeditious healing of chronic wounds with bacterial infections poses a formidable challenge in clinical practice because of the persistent bacterial presence, excessive inflammation, and the accumulation of reactive oxygen species (ROS) in clinical practice. Thus, in this study, natural antimicrobial material microneedles (MNs) with multifunctional properties were prepared by adding peony leaf extract (PLE) into a matrix of methacrylated Bletilla striata polysaccharide (BSPMA) and methacrylated chitosan (CSMA) via cross-linking under ultra-violet light to accelerate the rapid healing of chronic wounds with bacterial infections. Results showed that BCP-MNs effectively inhibited the growth of Escherichia coli, Staphylococcus aureus, and methicillin-resistant S. aureus (MRSA) by disrupting bacterial cell membranes and accelerated the healing of infected wounds by enhancing cell migration, epidermal regeneration, pro-collagen deposition, and angiogenesis and reducing inflammation. Furthermore, BCP-MNs not only possessed good mechanical properties, stability, and biocompatibility but also showed potent antioxidant effects to eliminate excessive ROS accumulation in the wound bed. In conclusion, BCP-MNs possess multifunctional wound-healing properties and can serve as excellent wound dressing in to treat infected wounds.

Antimicrobial and Cytotoxic Activities of Water-Soluble Isoxazole-Linked 1,3,4-Oxadiazole with Delocalized Charge: In Vitro and In Vivo Results.

The distinct structure of cationic organic compounds plays a pivotal role in enhancing their water solubility, which in turn influences their bioavailability. A representative of these compounds, which contains a delocalized charge, is 5-amino-2-(5-amino-3-methyl-1,2-oxazol-4-yl)-3-methyl-2,3-dihydro-1,3,4-oxadiazol-2-ylium bromide (ED). The high-water solubility of ED obviates the need for potentially harmful solvents during in vitro testing. The antibacterial and antifungal activities of the ED compound were assessed in vitro using the microtiter plate method and a biocellulose-based biofilm model. Additionally, its cytotoxic effects on wound bed fibroblasts and keratinocytes were examined. The antistaphylococcal activity of ED was also evaluated using an in vivo larvae model of Galleria mellonella. Results indicated that ED was more effective against Gram-positive bacteria than Gram-negative ones, exhibiting bactericidal properties. Furthermore, ED demonstrated greater efficacy against biofilms formed by Gram-positive bacteria. At bactericidal concentrations, ED was non-cytotoxic to fibroblasts and keratinocytes. In in vivo tests, ED was non-toxic to the larvae. When co-injected with a high load of S. aureus, it reduced the average larval mortality by approximately 40%. These findings suggest that ED holds promise for further evaluation as a potential treatment for biofilm-based wound infections, especially those caused by Gram-positive pathogens like S. aureus.