A Clinical Decision Support Tool for the Management of Diabetes-Related Foot Ulcers (DRFUs) Using a Topical Haemoglobin Spray

Diabetes related foot ulcers (DFUs) are complex and costly to manage, with the prevalence of non-healing wounds steadily increasing across the globe. Non-healing wounds can occur when clinicians fail to undertake an appropriate assessment, fail to recognise the importance of systemic or local complications, or provide the optimal treatment. The aetiological causes behind non-healing wounds are multifactorial; however, the purpose of this article is to focus on the role of oxygen in non-healing wounds and to introduce readers to advances in the delivery of topical oxygen therapy (TOT) via a haemoglobin spray. Importantly, this article incorporates a clinical decision support tool (CDST) to help clinicians identify the most appropriate individuals for whom topical haemoglobin may be most beneficial and the most appropriate time for introducing the intervention to improve wound healing outcomes.

Nanozyme-driven multifunctional dressings: moving beyond enzyme-like catalysis in chronic wound treatment

The treatment of chronic wounds presents significant challenges due to the necessity of accelerating healing within complex microenvironments characterized by persistent inflammation and biochemical imbalances. Factors such as bacterial infections, hyperglycemia, and oxidative stress disrupt cellular functions and impair angiogenesis, substantially delaying wound repair. Nanozymes, which are engineered nanoscale materials with enzyme-like activities, offer distinct advantages over conventional enzymes and traditional nanomaterials, making them promising candidates for chronic wound treatment. To enhance their clinical potential, nanozyme-based catalytic systems are currently being optimized through formulation advancements and preclinical studies assessing their biocompatibility, anti-oxidant activity, antibacterial efficacy, and tissue repair capabilities, ensuring their safety and clinical applicability. When integrated into multifunctional wound dressings, nanozymes modulate reactive oxygen species levels, promote tissue regeneration, and simultaneously combat infections and oxidative damage, extending beyond conventional enzyme-like catalysis in chronic wound treatment. The customizable architectures of nanozymes enable precise therapeutic applications, enhancing their effectiveness in managing complex wound conditions. This review provides a comprehensive analysis of the incorporation of nanozymes into wound dressings, detailing fabrication methods and emphasizing their transformative potential in chronic wound management. By identifying and addressing key limitations, we introduce strategic advancements to drive the development of nanozyme-driven dressings, paving the way for next-generation chronic wound treatments.

Topical Oxygenation Improves Microvascularity in a Human Ex Vivo Palatal Tissue Model: A Histological Analysis

Background: Several therapies involving the use of oxygen have been developed; however, the literature to date has poorly addressed the effects of Topical Oxygen Therapy (TOT) on oral tissues. The aim of the present pilot study was to histologically evaluate the response to TOT in epithelial-connective samples harvested from the palate. Methods: In eight patients selected for a free gingival graft (FGG) procedure, the lateral portions of the graft were randomly assigned to receive TOT (test) or no treatment (control). Both the portions were stained with hematoxylin-eosin for the evaluation of histomorphological changes and with Picrosirius for the study of collagen. Immunohistochemical staining was performed with antibodies for the characterization of the inflammatory infiltrate and neoangiogenesis. Results: The analysis failed to show morphological variations in both groups, demonstrating that there was no tissue damage due to TOT. The prevalence of type I collagen in both samples supported this finding. Immune cells were present in low levels and mainly consisted of CD3+ T lymphocytes. The histomorphometric analysis showed an increased average vessel area (7607.95 μm2 ± 3983.24 vs. 4038.42 μm2 ± 1823.52), an increased number and caliber of vessels (49.82 ± 20.55 vs. 32.35 ± 16.64), and a higher microvessel density (7.89 ± 3.25 vessels/0.26 mm2 vs. 5.13 ± 2.63 vessels/0.26 mm2) in the test group. Conclusions: Although further investigations are needed, TOT could improve and speed up oral wound healing through the local condition of hyperoxia.

Anaerobic bacteria in chronic wounds: Roles in disease, infection and treatment failure

Infection is among the most common factors that impede wound healing, yet standard treatments routinely fail to resolve chronic wound infections. The chronic wound environment is largely hypoxic/anoxic, and wounds are predominantly colonised by facultative and obligate anaerobic bacteria. Oxygen (O2) limitation is an underappreciated driver of microbiota composition and behaviour in chronic wounds. In this perspective article, we examine how anaerobic bacteria and their distinct physiologies support persistent, antibiotic-recalcitrant infections. We describe the anaerobic energy metabolisms bacteria rely on for long-term survival in the wound environment, and why many antibiotics become less effective under hypoxic conditions. We also discuss obligate anaerobes, which are among the most prevalent taxa to colonise chronic wounds, yet their potential roles in influencing the microbial community and wound healing have been overlooked. All of the most common obligate anaerobes found in chronic wounds are opportunistic pathogens. We consider how these organisms persist in the wound environment and interface with host physiology to hinder wound healing processes or promote chronic inflammation. Finally, we apply our understanding of anaerobic physiologies to evaluate current treatment practices and to propose new strategies for treating chronic wound infections.

CD9 promotes TβR2-TβR1 association driving the transition of human dermal fibroblasts to myofibroblast under hypoxia

BACKGROUND

During wound healing, fibroblast to myofibroblast transition is required for wound contraction and remodeling. While hypoxia is an important biophysical factor in wound microenvironment, the exact regulatory mechanism underlying hypoxia and fibroblast-to-myofibroblast transition remains unclear. We previously found that tetraspanin CD9 plays an important role in oxygen sensing and wound healing. Herein, we investigated the effects of physiological hypoxia on fibroblast-to-myofibroblast transition and the biological function and mechanism of CD9 in it.

METHODS

Human skin fibroblasts (HSF) and mouse dermis wounds model were established under physiological hypoxia (2% O2). The cell viability and contractility of HSF under hypoxia were evaluated by CCK8 and collagen gel retraction, respectively. The expression and distribution of fibroblast-to-myofibroblast transition markers and CD9 in HSF were detected by Western blotting and immunofluorescence. CD9 slicing and overexpressing HSFs were constructed to determine the role of CD9 by small interfering RNA and recombinant adenovirus vector. The association of TβR2 and TβR1 was measured by immunoprecipitation to explore the regulatory mechanism. Additionally, further validation was conducted on mouse dermis wounds model through histological analysis.

RESULTS

Enhanced fibroblast-to-myofibroblast transition and upregulated CD9 expression was observed under hypoxia in vitro and in vivo. Besides, reversal of fibroblast-to-myofibroblast transition under hypoxia was observed when silencing CD9, suggesting that CD9 played a key role in this hypoxia-induced transition. Moreover, hypoxia increased fibroblast-to-myofibroblast transition by activating TGF-β1/Smad2/3 signaling, especially increased interaction of TβR2 and TβR1. Ultimately, CD9 was determined to directly affect TβR1-TβR2 association in hypoxic fibroblast.

CONCLUSION

Collectively, these findings suggest that CD9 promotes TβR2-TβR1 association, thus driving the transition of human dermal fibroblasts to myofibroblast under hypoxia.

Risk Factors for Dehiscence of Operative Incisions in Newborns after Laparotomy

BACKGROUND

 Surgical wound dehiscence (SWD) in neonates is a life-threatening complication. The aim was to define risk factors of postoperative incision dehiscence in this population.

METHODS

 Data of 144 patients from 2010 to 2020 were analyzed retrospectively. All full-term newborns or preterm newborns up to 42 weeks of amenorrhea (adjusted) who had a laparotomy within 30 days were included. Descriptive patient information and perioperative data were collected. SWD was defined as any separation of cutaneous edges of postoperative wounds.

RESULTS

 Overall, SWD occurred in 16/144 (11%) patients, with a significantly increased incidence in preterm newborns (13/59, 22%) compared with full-term newborns (3/85, 4%; p < 0.001). SWD was significantly associated with exposure to postnatal steroids (60% vs. 4%, p < 0.001) and nonsteroidal anti-inflammatory drugs (25% vs. 4%, p < 0.01), invasive ventilation duration before surgery (median at 10 vs. 0 days, p < 0.001), preoperative low hemoglobin concentration (115 vs. 147 g/L, p < 0.001) and platelet counts (127 vs. 295 G/L, p < 0.001), nonabsorbable suture material (43% vs. 8%, p < 0.001), the presence of ostomies (69% vs. 18%, p < 0.001), positive bacteriological wound cultures (50% vs. 6%, p < 0.001), and relaparotomy (25% vs. 3%, p < 0.01). Thirteen of 16 patients with SWD presented necrotizing enterocolitis/intestinal perforations (81%, p < 0.001).

CONCLUSION

 This study identified prematurity and a number of other factors linked to the child's general condition as risk factors for SWD. Some of these can help physicians recognize and respond to at-risk patients and provide better counseling for parents.

Evaluation of wound healing and anti-inflammatory activity of hydro-alcoholic extract and solvent fractions of the leaves of Clerodendrum myricoides (Lamiaceae) in mice

BACKGROUND

Wounds significantly affect people's quality of life and the clinical and financial burden of healthcare systems around the world. Many of the current drugs used to treat wounds have problems such as; allergies and drug resistance. Hence, the exploration of new therapeutic agents from natural origin may avert this problem. Clerodendrum myricoides have long been used to treat wounds in Ethiopia. Despite this, nothing has so far been reported about the wound healing and anti-inflammatory activity of C. myricoides. This study aimed to evaluate the wound healing and anti-inflammatory activity of 80% methanol extract and solvent fractions of C. myricoides leaves in mice.

METHODS

Leaves of C. myricoides were extracted using the maceration technique. The extract was formulated as 5% and 10% w/w ointments. The wound healing activity of the extract was evaluated using excision, incision, and burn wound models whereas the healing activities of solvent fractions were evaluated using the excision wound model. A carrageenan-induced paw edema model was used for the anti-inflammatory test.

RESULTS

In the dermal toxicity test, 2000 mg/kg of 10% extract was found to be safe. In excision and burn wound models, treatment with 10% and 5% extract showed a significant (p<0.001) wound contraction. Solvent fractions of the extract significantly reduced wound contraction. A significant reduction in periods of epithelialization and favorable histopathology changes were shown by extract ointments. In incision wounds, 10% (p<0.001) and 5% (p<0.01) extracts significantly increase skin-breaking strength. After one hour of treatment, 400 mg/kg (p<0.001) and 200 mg/kg (p<0.05) showed significant reduction in paw edema.

CONCLUSION

Results of this study indicate that 80% methanol extract and the solvent fraction of the leaves of C. myricoides possess wound-healing and anti-inflammatory activity and support traditional claims.

Nanomaterial-related hemoglobin-based oxygen carriers, with emphasis on liposome and nano-capsules, for biomedical applications: current status and future perspectives

Oxygen is necessary for life and plays a key pivotal in maintaining normal physiological functions and treat of diseases. Hemoglobin-based oxygen carriers (HBOCs) have been studied and developed as a replacement for red blood cells (RBCs) in oxygen transport due to their similar oxygen-carrying capacities. However, applications of HBOCs are hindered by vasoactivity, oxidative toxicity, and a relatively short circulatory half-life. With advancements in nanotechnology, Hb encapsulation, absorption, bioconjugation, entrapment, and attachment to nanomaterials have been used to prepare nanomaterial-related HBOCs to address these challenges and pend their application in several biomedical and therapeutic contexts. This review focuses on the progress of this class of nanomaterial-related HBOCs in the fields of hemorrhagic shock, ischemic stroke, cancer, and wound healing, and speculates on future research directions. The advancements in nanomaterial-related HBOCs are expected to lead significant breakthroughs in blood substitutes, enabling their widespread use in the treatment of clinical diseases.

Oxygen Delivery Biomaterials in Wound Healing Applications

Oxygen (O2 ) delivery biomaterials have attracted great interest in the treatment of chronic wounds due to their potential applications in local and continuous O2 generation and delivery, improving cell viability until vascularization occurs, promoting structural growth of new blood vessels, simulating collagen synthesis, killing bacteria and reducing hypoxia-induced tissue damage. Therefore, different types of O2 delivery biomaterials including thin polymer films, fibers, hydrogels, or nanocomposite hydrogels have been developed to provide controlled, sufficient and long-lasting O2 to prevent hypoxia and maintain cell viability until the engineered tissue is vascularized by the host system. These biomaterials are made by various approaches, such as encapsulating O2 releasing molecules into hydrogels, polymer microspheres and 3D printed hydrogel scaffolds and adsorbing O2 carrying reagents into polymer films of fibers. In this article, different O2 generating sources such as solid inorganic peroxides, liquid peroxides, and photosynthetic microalgae, and O2 carrying perfluorocarbons and hemoglobin are presented and the applications of O2 delivery biomaterials in promoting wound healing are discussed. Furthermore, challenges encountered and future perspectives are highlighted.

Oxygen-Generating Hydrogels as Oxygenation Therapy for Accelerated Chronic Wound Healing

Hypoxia in chronic wounds impairs the activities of reparative cells, resulting in tissue necrosis, bacterial infections, decreased angiogenesis, and delayed wound healing. To achieve effective oxygenation therapy and restore oxygen homeostasis, oxygen-generating hydrogels based on different oxygen sources have been developed to release dissolved oxygen in the wound bed, which not only alleviate hypoxia, but also accelerate chronic wound healing. This review first discusses the vital role of oxygen and hypoxia in the wound healing process. The advancements in oxygen-generating hydrogels, which produce oxygen through the decomposition of hydrogen peroxide, metal peroxides, glucose-activated cascade reactions, and photosynthesis of algae microorganisms for chronic wound healing, are discussed and summarized. The therapeutic effects and challenges of using oxygen-generating hydrogels for the clinical treatment of chronic wounds are concluded and prospected.

Hard-to-Heal Wound Healing: Superiority of Hydrogel EHO-85 (Containing Olea europaea Leaf Extract) vs. a Standard Hydrogel. A Randomized Controlled Trial

Chronic wounds, especially those that are hard-to-heal, constitute a serious public-health problem. Although progress has been made in the development of wound dressings for healing, there is little high-quality evidence of their efficacy, with no evidence of superiority in the use of one hydrogel over another. To evaluate the superiority of a hydrogel (EHO-85), containing Olea europaea leaf extract (OELE), over a standard hydrogel (SH), the promotion and/or improvement of healing of difficult-to-heal wounds was compared in a prospective, parallel-group multicenter, randomized, observer-blinded, controlled trial ("MACAON"). Non-hospitalized patients with pressure, venous or diabetic foot-ulcers difficult-to-heal were recruited and treated with standard care, and EHO-85 (n = 35) or VariHesive (n = 34) as SH. Wound-area reduction (WAR; percentage) and healing rate (HR; mm2/day) were measured. EHO-85 showed a statistically significant superior effect over VariHesive. At the end of the follow-up period, the relative WAR decreased by 51.6% vs. 18.9% (p < 0.001), with a HR mean of 10.5 ± 5.7 vs. 1.0 ± 7.5 mm2/day (p = 0.036). EHO-85 superiority is probably based on its optimal ability to balance the ulcer bed, by modulating pH and oxidative stress. That complements the wetting and barrier functions, characteristics of conventional hydrogels. These results support the use of EHO-85 dressing, for treatment of hard-to-heal ulcers. Trial Registration AEMPS:PS/CR623/17/CE.

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 oxydevice is 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.

Recent advances in biosensors for real time monitoring of pH, temperature, and oxygen in chronic wounds

Chronic wounds are among the major healthcare issues affecting millions of people worldwide with high rates of morbidity, losses of limbs and mortality. Microbial infection in wounds is a severe problem that can impede healing of chronic wounds. Accurate, timely and early detection of infections, and real time monitoring of various wound healing biomarkers related to infection can be significantly helpful in the treatment and care of chronic wounds. However, clinical methodologies of periodic assessment and care of wounds require physical visit to wound care clinics or hospitals and time-consuming frequent replacement of wound dressing patches, which also often adversely affect the healing process. Besides, frequent replacements of wound dressings are highly expensive, causing a huge amount of burden on the national health care systems. Smart bandages have emerged to provide in situ physiochemical surveillance in real time at the wound site. These bandages integrate smart sensors to detect the condition of wound infection based on various parameters, such as pH, temperature and oxygen level in the wound which reduces the frequency of changing the wound dressings and its associated complications. These devices can continually monitor the healing process, paving the way for tailored therapy and improved quality of patient's life. In this review, we present an overview of recent advances in biosensors for real time monitoring of pH, temperature, and oxygen in chronic wounds in order to assess infection status. We have elaborated the recent progress in quantitative monitoring of several biomarkers important for assessing wounds infection status and its detection using smart biosensors. The review shows that real-time monitoring of wound status by quantifying specific biomarkers, such as pH, temperature and tissue oxygenation to significantly aid the treatment and care of chronic infected wounds.

Biomedical applications of MnO2 nanomaterials as nanozyme-based theranostics

Manganese dioxide (MnO₂) nanoenzymes/nanozymes (MnO₂-NEs) are 1-100 nm nanomaterials that mimic catalytic, oxidative, peroxidase, and superoxide dismutase activities. The oxidative-like activity of MnO₂-NEs makes them suitable for developing effective and low-cost colorimetric detection assays of biomolecules. Interestingly, MnO₂-NEs also demonstrate scavenging properties against reactive oxygen species (ROS) in various pathological conditions. In addition, due to the decomposition of MnO₂-NEs in the tumor microenvironment (TME) and the production of Mn²⁺, they can act as a contrast agent for improving clinical imaging diagnostics. MnO₂-NEs also can use as an in situ oxygen production system in TME, thereby overcoming hypoxic conditions and their consequences in the progression of cancer. Furthermore, MnO₂-NEs as a shell and coating make the nanosystems smart and, therefore, in combination with other nanomaterials, the MnO₂-NEs can be used as an intelligent nanocarrier for delivering drugs, photosensitizers, and sonosensitizers in vivo. Moreover, these capabilities make MnO₂-NEs a promising candidate for the detection and treatment of different human diseases such as cancer, metabolic, infectious, and inflammatory pathological conditions. MnO₂-NEs also have ROS-scavenging and anti-bacterial properties against Gram-positive and Gram-negative bacterial strains, which make them suitable for wound healing applications. Given the importance of nanomaterials and their potential applications in biomedicine, this review aimed to discuss the biochemical properties and the theranostic roles of MnO₂-NEs and recent advances in their use in colorimetric detection assays of biomolecules, diagnostic imaging, drug delivery, and combinatorial therapy applications. Finally, the challenges of MnO₂-NEs applications in biomedicine will be discussed.

Vaginal oxygen plus hyaluronic acid on genito-urinary symptoms of breast cancer survivors

OBJECTIVES

This study aimed to evaluate the efficacy of vaginal oxygen and hyaluronic acid on genito-urinary symptoms of breast cancer survivors.

METHODS

Patients were enrolled at the Menopause Outpatient Clinic of a university hospital. Breast cancer patients in a stable relationship, suffering from vaginal atrophy (VA) consequent to hypoestrogenism, were included. Natural oxygen was introduced into the vagina for 15 min, coupled in the last 5 min with a 2% solution of hyaluronic acid. Treatment was repeated five times, every 15 days.

RESULTS

Out of the 40 breast cancer patients enrolled, 65% had no sexual intercourse due to pain. During treatment, the Vaginal Health Index Score gradually improved from 9.5 ± 2.2 to 16.8 ± 2.8 (p < 0.001), the visual analog scale score for dyspareunia decreased from 8.9 ± 1.3 to 3.4 ± 2.1 (p < 0.001) and the Female Sexual Function Index increased from 8.6 ± 6.3 to 15.2 ± 8.1 (p < 0.001). At the end of treatment, only 15% women (p = 0.001 vs. pretreatment) had no intercourse due to pain. Benefits remained 30 days after last treatment.

CONCLUSION

Vaginal oxygenation coupled with hyaluronic acid every 15 days improves VA, sexuality and urinary symptoms of breast cancer patients. Beside data confirmation, additional studies are needed to determine the best interval between treatments, the optimal length of treatment and the long-term duration of the benefits.

Transdermal drug delivery via microneedles to mediate wound microenvironment

Cutaneous wound healing is a complex process, while modulating the wound microenvironment has become an essential therapeutic goal. In clinics, advanced dressings or dermal templates can promote wound healing but their ability in mediating wound microenvironment is limited. In the last decade, microneedle (MN) array patches have emerged as a new class of wound dressings. These dressings enable non-invasive transdermal and precise medication delivery. Combined with smart materials, MN additionally allows real-time monitoring of wound site markers such as inflammatory factors, oxygen levels, vascularization, pH and temperature, etc., while releasing therapeutic molecules responsively to the wound site. In this review, the MN-based strategies were reviewed for modulating wound microenvironment via introducing the main characteristics of the wound microenvironment and various types of MN-based delivery systems. Additionally, the progress and future trends in the application of MNs in mediating wound microenvironments are also discussed.

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

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

The initiation of oxidative stress and therapeutic strategies in wound healing

When the production of reactive oxygen species (ROS) is overloaded surpassing the capacity of the reductive rheostat, mammalian cells undergo a series of oxidative damage termed oxidative stress (OS). This phenomenon is ubiquitously detected in many human pathological conditions. Wound healing program implicates continuous neovascularization, cell proliferation, and wound remodeling. Increasing evidence indicates that reactive oxygen species (ROS) have profound impacts on the wound healing process through regulating a series of the physiological and pathological program including inflammatory response, cell proliferation, angiogenesis, granulation as well as extracellular matrix formation. In most pathological wound healing processes, excessive ROS exerts a negative role on the wound healing process. Interestingly, the moderate increase of ROS levels is beneficial in killing bacteria at the wound site, which creates a sterile niche for revascularization. In this review, we discussed the physiological rhythms of wound healing and the role of ROS in this progress, aim to explore the potential manipulation of OS as a promising therapeutic avenue.

Case report: Long-term follow-up of a large full-thickness skin defect treated with a photosynthetic scaffold for dermal regeneration

It is broadly described that almost every step of the regeneration process requires proper levels of oxygen supply; however, due to the vascular disruption in wounds, oxygen availability is reduced, being detrimental to the regeneration process. Therefore, the development of novel biomaterials combined with improved clinical procedures to promote wound oxygenation is an active field of research in regenerative medicine. This case report derives from a cohort of patients enrolled in a previously published ongoing phase I clinical trial (NCT03960164), to assess safety of photosynthetic scaffolds for the treatment of full skin defects. Here, we present a 56 year old patient, with a scar contracture in the cubital fossa, which impaired the elbow extension significantly affecting her quality of life. As part of the treatment, the scar contracture was removed, and the full-thickness wound generated was surgically covered with a photosynthetic scaffold for dermal regeneration, which was illuminated to promote local oxygen production. Then, in a second procedure, an autograft was implanted on top of the scaffold and the patient's progress was followed for up to 17 months. Successful outcome of the whole procedure was measured as improvement in functionality, clinical appearance, and self-perception of the treated area. This case report underscores the long-term safety and applicability of photosynthetic scaffolds for dermal regeneration and their stable compatibility with other surgical procedures such as autograft application. Moreover, this report also shows the ability to further improve the clinical outcome of this procedure by means of dermal vacuum massage therapy and, more importantly, shows an overall long-term improvement in patient´s quality of life, supporting the translation of photosynthetic therapies into human patients.

A Narrative Review on Means to Promote Oxygenation and Angiogenesis in Oral Wound Healing

Oral mucosa serves as the primary barrier against pathogen invasions, mechanical stresses, and physical trauma. Although it is generally composed of keratinocytes and held in place by desmosomes, it shows variation in tissue elasticity and surface keratinization at different sites of the oral cavity. Wound healing undergoes four stages of tissue change sequences, namely haemostasis, inflammation, proliferation, and remodelling. The wound healing of oral hard tissue and soft tissue is largely dependent on the inflammatory response and vascular response, which are the targets of many research. Because of a less-robust inflammatory response, favourable saliva properties, a unique oral environment, and the presence of mesenchymal stem cells, oral wounds are reported to demonstrate rapid healing, less scar formation, and fewer inflammatory reactions. However, delayed oral wound healing is a major concern in certain populations with autoimmune disorders or underlying medical issues, or those subjected to surgically inflicted injuries. Various means of approach have been adopted to improve wound tissue proliferation without causing excessive scarring. This narrative review reappraises the current literature on the use of light, sound, mechanical, biological, and chemical means to enhance oxygen delivery to wounds. The current literature includes the use of hyperbaric oxygen and topical oxygen therapy, ultrasounds, lasers, platelet-rich plasma (PRP)/platelet-rich fibrin (PRF), and various chemical agents such as hyaluronic acid, astaxanthin, and Centella asiatica to promote angiogenesis in oral wound healing during the proliferation process. The arrival of a proprietary oral gel that is reported to improve oxygenation is highlighted.

How Microalgae is Effective in Oxygen Deficiency Aggravated Diseases? A Comprehensive Review of Literature

Hypoxia can aggravate the conditions of many oxygen-deficiency-aggravated diseases (ODAD), such as cancer, ischemic heart disease, and chronic wounds. Photosynthetic microalgae can alleviate the hepatotoxicity of the local microenvironment by producing oxygen. In addition, microalgae extracts have antitumor, anti-inflammatory, antibacterial, and antioxidant effects. These properties make them attractive candidates for developing methods to treat ODAD. Although researchers have exploited the advantages of microalgae and developed a variety of microalgae-based biomaterials to treat ODAD, a comprehensive review of this topic has not been presented previously. Therefore, in this review, we summarize the development and progress made in the field of developing microalgae-based biomaterials toward the treatment of ODAD. The challenges and prospects of this field are also discussed.

Smoking increases the risk of postoperative wound complications: A propensity score-matched cohort study

Cigarette smoking is associated with surgical complications, including wound healing and surgical site infection. However, the association between smoking status and postoperative wound complications is not completely understood. Our objective was to investigate the effect of smoking on postoperative wound complications for major surgeries. Data were collected from the 2013 to 2018 participant use files of the American College of Surgeons National Surgical Quality Improvement Program database. A propensity score matching procedure was used to create the balanced smoker and nonsmoker groups. Multivariable logistic regression was used to calculate the odds ratios (ORs) with 95% confidence intervals (CIs) for postoperative wound complications, pulmonary complications, and in-hospital mortality associated with smokers. A total of 1 156 002 patients (578 001 smokers and 578 001 nonsmokers) were included in the propensity score matching analysis. Smoking was associated with a significantly increased risk of postoperative wound disruption (OR 1.65, 95% CI 1.56-1.75), surgical site infection (OR 1.31, 95% CI 1.28-1.34), reintubation (OR 1.47, 95% CI 1.40-1.54), and in-hospital mortality (OR 1.13, 95% CI 1.07-1.19) compared with nonsmoking. The length of hospital stay was significantly increased in smokers compared with nonsmokers. Our analysis indicates that smoking is associated with an increased risk of surgical site infection, wound disruption, and postoperative pulmonary complications. The results may drive the clinicians to encourage patients to quit smoking before surgery.

Skin γδ T Cells and Their Function in Wound Healing

For the skin immune system, γδ T cells are important components, which help in defensing against damage and infection of skin. Compared to the conventional αβ T cells, γδ T cells have their own differentiation, development and activation characteristics. In adult mice, dendritic epidermal T cells (DETCs), Vγ4 and Vγ6 γδ T cells are the main subsets of skin, the coordination and interaction among them play a crucial role in wound repair. To get a clear overview of γδ T cells, this review synopsizes their derivation, development, colonization and activation, and focuses their function in acute and chronic wound healing, as well as the underlining mechanism. The aim of this paper is to provide cues for the study of human epidermal γδ T cells and the potential treatment for skin rehabilitation.

Hyperbaric oxygen therapy: when pressure is good for diabetic foot ulcers

The diabetic foot ulcer (DFU) as a common complication of diabetes. Even with adequate treatment, up to 35% of these ulcers do not heal. This is due to the effect of aging, repeated ischemia-reperfusion (IR) injury, bacterial colonisation of the wound and chronic hypoxia. All wound-healing processes are highly dependent on oxygen, so hyperbaric oxygen therapy (HBOT) can be employed to improve wound healing and correct the four pathophysiological factors for chronic wounds. It is, in fact, internationally recognised as a treatment option for non-healing DFUs. Several trials and systematic reviews have been performed on its efficacy, which show a positive trend towards increased wound healing and reduced amputation risk. Some controversy exists due to contradictory results in these studies, which may be due to grouping patients with and without peripheral arterial occlusive disease (PAOD) together. Side effects are usually mild and transient, and the treatment is considered safe.

Duration of postoperative hyperlactatemia has predictive value in recurrent fistula after major definitive surgery for intestinal fistula

PURPOSE

The present study aimed to identify the predictive value of duration of postoperative hyperlactatemia in screening patients at high risk of recurrent fistula after major definitive surgery (DS) for intestinal fistula.

METHODS

If the initial postoperative lactate (IPL) > 2 mmol/L, DS was defined as major definitive surgery. The 315 enrolled patients with major DS were divided into group A (2 mmol/L < IPL ≤ 4 mmol/L), group B (mmol/L < IPL ≤ 6 mmol/L), and group C (IPL > 6 mmol/L). The characteristics of patients were collected, and the duration of postoperative hyperlactatemia was analyzed. According to the occurrence of recurrent fistula (RF), patients were further divided into RF group A, and Non-RF group A; RF group B, and Non-RF group B; and RF group C, and Non-RF group C.

RESULTS

The duration of postoperative hyperlactatemia was comparable between the RF group A and the Non-RF group A [12 (IQR: 12-24) vs 24 (IQR: 12-24), p = 0.387]. However, the duration of hyperlactatemia was associated with RF in group B (adjusted OR = 1.061; 95% CI: 1.029-1.094; p < 0.001) and group C (adjusted OR = 1.059; 95% CI: 1.012-1.129; p = 0.017). In group B, the cutoff point of duration of 42 h had the optimal predictive value (area under ROC = 0.791, sensitivity = 0.717, specificity = 0.794, p < 0.001). In group C, the cutoff point of duration of 54 h had the optimal predictive value (area under ROC = 0.781, sensitivity = 0.730, specificity = 0.804, p < 0.001).

CONCLUSION

The duration of postoperative hyperlactatemia has a value in predicting RF in patients with an IPL of more than 4 mmol/L after major definitive surgery for intestinal fistula.

Oxygenation therapies for improved wound healing: Current trends and technologies

Degree of oxygenation is one of the important parameters governing various processes, including cell proliferation, angiogenesis, extracellular matrix production, and even combating the microbial burden at the wound site, all...

Plasma TNFα and Unknown Factor/s Potentially Impede Erythroblast Enucleation Obstructing Terminal Maturation of Red Blood Cells in Burn Patients

INTRODUCTION

In this study, using burn patient's peripheral blood mononuclear cells (PBMCs), we have shown that the Epo independent stage of terminal enucleation to reticulocyte formation is impeded in the presence of autologous plasma (BP). Furthermore, substitution with allogeneic control plasma (CP) from the healthy individual in place of BP rectified this enucleation defect. The exclusive role of burn microenvironment in late-stage erythropoiesis defect was further demarcated through control healthy human bone marrow cells cultured in the presence of CP, BP, and cytokines.

METHODS

PBMCs and human bone marrow (huBM) were differentiated ex vivo to enucleated reticulocytes in the presence of required growth factors and 5% CP or BP. Effect of systemic mediators in burn microenvironment like IL-6, IL-15, and TNFα was also explored. Neutralization experiments were carried out by adding varying concentrations (25 ng-400 ng/mL) of Anti-TNFα Ab to either CP+TNFα or BP.

RESULTS

Reticulocyte proportion and maturation index were significantly improved upon substituting BP with CP during differentiation of burn PBMCs. In the huBM ex vivo culture, addition of IL-6 and IL-15 to CP inhibited the proliferation stages of erythropoiesis, whereas TNFα supplementation caused maximum diminution at erythroblast enucleation stage. Supplementation with anti-TNFα in the BP showed significant but partial restoration in the enucleation process, revealing the possibility of other crucial microenvironmental factors that could impact RBC production in burn patients.

CONCLUSION

Exogenous TNFα impairs late-stage erythropoiesis by blocking enucleation, but neutralization of TNFα in BP only partially restored terminal enucleation indicating additional plasma factor(s) impair(s) late-stage RBC maturation in burn patients.