Oxygen therapies and their effects on wound healing

Development of an aminoguanidine hybrid hydrogel composites with hydrogen and oxygen supplying performance to boost infected diabetic wound healing

Diabetic wounds tend to develop into non-healing wounds associated with a complex inflammatory microenvironment of uncontrollable bacterial infection, reactive oxygen species (ROS) accumulation, and chronic hypoxia. This study developed a multifunctional hydrogel system by integrating aminoguanidine and hydrogen and oxygen gas-release nanoparticles (PAP NPs) into phenylboronic acid-modified quaternized chitosan and an oxidized dextran network. Hollow mesoporous Prussian blue (HPB) nanozymes with superoxide dismutase- and catalase-like activities are promising bioreactors for simultaneously alleviating ROS accumulation and hypoxia by converting elevated endogenous hydrogen peroxide (H2O2) into oxygen in diabetic wounds. Simultaneously, incorporating ammonia borane (AB)-loaded HPB NPs served as a source of hydrogen, further reducing ROS overproduction and modulating pro-inflammatory cytokine responses. Aminoguanidine in the hydrogel network inhibits the formation of advanced glycation end products (AGEs), inhibiting skin cell apoptosis and promoting their proliferation and migration. Moreover, the hydrogel exhibited significant mechanical characteristics and self-healing capacity owing to the Schiff base and phenylboronate ester linkages. Incorporating PAP NPs into the hydrogel produced an exceptional photothermal response, effectively eradicating bacteria with a mortality rate exceeding 95 % within 10 min and protecting the wound from potential infections. In vivo studies demonstrated that PAP@Gel significantly accelerated the healing of infected diabetic wounds by mitigating oxidative stress, enhancing oxygenation, inhibiting inflammation and AGE formation, and reversing bacterial infections. This study highlights a promising nanomedicine approach for designing future diabetic wound dressings, providing a novel strategy for catalytic ROS scavenging and synergistic hydrogen and oxygen therapies.

Analysis of microbial environment changes in wound healing of pressure ulcers in rats promoted by moist exposed burn ointment

This study explored the effects of Moist Exposed Burn Ointment (MEBO) on the healing process of pressure-induced wounds. Using a stage IV pressure ulcer model established in 42 rats, divided equally into a control gel group and an MEBO group, we investigated the efficacy of MEBO through topical application. The control group received Carbomer gel, while the MEBO group was treated with MEBO until complete wound healing. Results showed that MEBO significantly accelerated wound healing compared to the control group. Histological analysis, including hematoxylin and eosin (HE) staining and Masson's trichrome staining, revealed enhanced epithelialization and collagen deposition in the MEBO group. Furthermore, 16S rRNA sequencing indicated that MEBO reduced microbial diversity at the wound site and reshaped the microbial composition. Notably, The increased abundance of Acinetobacter and Staphylococcus, coupled with a reduction in Pseudomonas, may reflect a shift in the wound microbiome that could be conducive to healing. However, the exact role of these microbial shifts in promoting wound healing requires further investigation, as microbial dynamics in wound environments are complex and context-dependent. These findings suggest that MEBO facilitates wound healing by optimizing the wound microbiome, thereby offering a promising therapeutic approach for managing pressure ulcers.

Accelerating healing at high altitudes: Oxygen and bFGF delivery through nanoparticle-loaded gel dressings

High altitude environment is mainly characterized by low oxygen. Due to persistent hypoxia, nonhealing wounds are common in high-altitude areas. Moreover, Basic fibroblast growth factor (bFGF) is a versatile biologically active substance that has crucial impact on wound healing. Given the limited availability of atmospheric oxygen and reduced blood oxygen saturation in high-altitude area, and the challenge that arises from direct oxygen and bFGF delivery to wounds through the traumatized vascular structure, it necessitates an innovative solution for local and permeable delivery of oxygen and bFGF. In this study, we present a strategy that involves revamping traditional gel-based wound dressings through the incorporation of nanoparticles encapsulating oxygen and bFGF, engineered to facilitate the localized delivery of dissolved oxygen and bFGF to wound surfaces. The prospective evaluation of this delivery technique's therapeutic impacts on epithelial, endothelial and fibroblasts cells can be materialized. Further experiment corroborated these effects on a high-altitude wounds' murine model. Given its biocompatibility, efficacy, and utility, we posit that NOB-Gel exhibits remarkable translational potential for managing and hastening the healing process of an array of clinical wounds, more so for wounds inflicted at high altitudes.

Nanomaterials-incorporated polymeric microneedles for wound healing applications

There is a growing and urgent need for developing novel biomaterials and therapeutic approaches for efficient wound healing. Microneedles (MNs), which can penetrate necrotic tissues and biofilm barriers at the wound and deliver active ingredients to the deeper layers in a minimally invasive and painless manner, have stimulated the interests of many researchers in the wound-healing filed. Among various materials, polymeric MNs have received widespread attention due to their abundant material sources, simple and inexpensive manufacturing methods, excellent biocompatibility and adjustable mechanical strength. Meanwhile, due to the unique properties of nanomaterials, the incorporation of nanomaterials can further extend the application range of polymeric MNs to facilitate on-demand drug release and activate specific therapeutic effects in combination with other therapies. In this review, we firstly introduce the current status and challenges of wound healing, and then outline the advantages and classification of MNs. Next, we focus on the manufacturing methods of polymeric MNs and the different raw materials used for their production. Furthermore, we give a summary of polymeric MNs incorporated with several common nanomaterials for chronic wounds healing. Finally, we discuss the several challenges and future prospects of transdermal drug delivery systems using nanomaterials-based polymeric MNs in wound treatment application.

Hydrogel-Based Oxygen and Drug Delivery Dressing for Improved Wound Healing

Herein, we propose a Carbopol hydrogel-based oxygen nanodelivery "nanohyperbaric" system as a wound dressing material for an enhanced wound healing process. Oxygen nanobubbles (ONBs) were used to supply oxygen, and collagenase was added in the gel as a drug model. Both oxygen and collagenase would benefit the wound healing process, and the Carbopol hydrogel serves as the matrix to load ONBs and collagenase in the wound dressing. The obtained ONB-embedded Carbopol hydrogel with collagenase (ONB-CC) could provide 12.08 ± 0.75 μg of oxygen from 1 mL of ONB-CC and exhibited a notable capacity to prolong the oxygen holding for up to 3 weeks and maintained the enzymatic activity of collagenase at more than 0.05 U per 0.1 mL of ONB-CC for up to 17 days. With HDFa cells, the ONB-CC did not show a notable effect on the cell viability. In a scratch assay, the oxygen from ONBs or collagenase aided cell migration; further, the ONB-CC induced the most obvious scratch closure, indicating an improvement in wound healing as a cocktail in the ONB-CC. The mRNA expression further demonstrated the effectiveness of the ONB-CC. Studies in rats with punched wounds treated with the ONB-CC dressing showed improved wound closure. Histopathological images showed that the ONB-CC dressing enhanced re-epithelization and formation of new blood vessels and hair follicles. The proposed ONB-CC has excellent potential as an ideal wound dressing material to accelerate wound healing by integration of multiple functions.

Topical oxygen therapy as a novel strategy to promote wound healing and control the bacteria in implantology, oral surgery and periodontology: A review

Globally, oral infections and inflammatory lesions persist as substantial public health concerns, necessitating the introduction of novel oral treatment protocols. Oral diseases are linked to various causative factors, with dental plaque/biofilm resulting from inadequate hygiene practices playing a predominant role. The strategic implementation of novel topical therapies holds promise for effectively controlling the biofilms, addressing oral infections and promoting enhanced oral wound healing. This review aims to providing a comprehensive overview of the available evidence pertaining to the potential efficacy of topical oxygen and lactoferrin-releasing biomaterials, exemplified by the blue®m formula, as novel oral care interventions within the scope of contemporary implantology, oral surgery and periodontology.

Nano oxygen chamber by cascade reaction for hypoxia mitigation and reactive oxygen species scavenging in wound healing

Hypoxia, excessive reactive oxygen species (ROS), and impaired angiogenesis are prominent obstacles to wound healing following trauma and surgical procedures, often leading to the development of keloids and hypertrophic scars. To address these challenges, a novel approach has been proposed, involving the development of a cascade enzymatic reaction-based nanocarriers-laden wound dressing. This advanced technology incorporates superoxide dismutase modified oxygen nanobubbles and catalase modified oxygen nanobubbles within an alginate hydrogel matrix. The oxygen nano chamber functions through a cascade reaction between superoxide dismutase and catalase, wherein excessive superoxide in the wound environment is enzymatically decomposed into hydrogen peroxide, and this hydrogen peroxide is subsequently converted into oxygen by catalase. This enzymatic cascade effectively controls wound inflammation and hypoxia, mitigating the risk of keloid formation. Concurrently, the oxygen nanobubbles release oxygen continuously, thus providing a sustained supply of oxygen to the wound site. The oxygen release from this dynamic system stimulates fibroblast proliferation, fosters the formation of new blood vessels, and contributes to the overall wound healing process. In the rat full-thickness wound model, the cascade reaction-based nano oxygen chamber displayed a notable capacity to expedite wound healing without scarring. Furthermore, in the pilot study of porcine full-thickness wound healing, a notable acceleration of tissue repair was observed in the conceived cascade reaction-based gel treated group within the 3 days post-surgery, which represents the proliferation stage of healing process. These achievements hold significant importance in ensuring the complete functional recovery of tissues, thereby highlighting its potential as a promising approach for enhancing wound healing outcomes.

Diabetic Foot Ulcer Management and Treatment: An Overview of Published Patents

BACKGROUND

One of the most challenging effects of diabetes is diabetic foot ulceration (DFU). DFU may occur in up to one-third of individuals with diabetes mellitus (D.M.) at some point in their lives. The major cause of morbidity in D.M. patients is DFU. The length of treatment is difficult, and DFU recurrence is common.

OBJECTIVE

The most crucial element for the treatment and prevention of DFUs require a multidisciplinary approach. Patients who are at risk should be identified, depending on the type of risk, prophylactic actions etc. It is imperative to identify at-risk patients and take preventative measures accordingly.

METHOD

The at-risk diabetes-related foot ulcer was identified based on the risk category classification, while the foot ulcers were evaluated using Wagner's classification system.

RESULTS

Literature reported that patients with lower limb vascular insufficiency, loss of vibratory sensation, or protective sensation loss have an increased risk of developing foot ulcers. Proper categorization and therapeutic measures will be implemented after the DFU has been formed. The appropriate assessment and management of general health status should include glycemic control, the diagnosis and treatment of vascular disease, standard care for wounds, diagnosis, and infection treatments.

CONCLUSION

The review reflects the updated awareness of the treatment and management of DFU based on the current and past literature and patent analysis.

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.

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.

An oxygen-releasing agent promotes healing of skin wounds in rats

OBJECTIVE

To evaluate the local effect of a slow oxygen-release gel on the healing of standardised skin wounds caused in rats.

METHOD

Skin wounds were created on the backs of male rats (Rattus norvegicus, Wistar) that were randomly allocated into two groups. In the treated (T) and control (C) groups, oxygen gel and distilled water, respectively, were applied to the wounds on alternate days for 28 days. Postoperatively, euthanasia was performed at 5, 10, 14, 21 and 28 days, followed by clinical, histological (Masson's trichrome) and immunohistochemical analysis. Data were subjected to analysis of variance (ANOVA) and Bonferroni's test.

RESULTS

The cohort comprised 50 rats. On clinical and histological analysis, groups C and T showed similar characteristics 5 days post-operation. Subsequently, group T showed better healing at 14, 21 and 28 days and presented more intense inflammatory infiltrate up to 10 days. At days 14, 21 and 28, group T exhibited a reduction in oedema and increased angiogenesis, granulation tissue formation, and deposition of collagen fibres than group C. Immunohistochemical analysis showed the presence of tumour necrosis factor (TNF)-α and vascular endothelial growth factor (VEGF) in both the groups, but the levels were significantly higher in group T (p<0.05).

CONCLUSION

The local application of slow oxygen-release gel accelerated the healing of standardised skin wounds created surgically in rats, with increased angiogenesis and better collagen fibre formation.

Effect of the Timing of Hyperbaric Oxygen Therapy on the Prognosis of Patients with Idiopathic Sudden Sensorineural Hearing Loss

This study aimed to evaluate the effects of hyperbaric oxygen therapy (HBOT) on the hearing recovery of patients with idiopathic sudden sensorineural hearing loss (ISSNHL). The clinical data of 79 patients diagnosed with ISSNHL and treated with HBOT between January 2017 and December 2019 were retrospectively reviewed. The pure tone audiometry (PTA) scores before and after HBOT were recorded. The associations of HBOT efficacy with demographic and clinical characteristics and the duration from disease onset to HBOT administration were determined. The average PTA score was 80.06 ± 25.94 dB before and 60.75 ± 21.26 dB after HBOT; the difference was significant. HBOT improved the hearing of 55.7% of the patients with ISSNHL (defined as an average PTA ≥ 11dB or a final average PTA score below 29 dB). There was a significant inverse relationship between the duration from symptom onset to HBOT administration and PTA score reduction after HBOT, which was adjusted for factors including age, sex, laterality of hearing loss, initial PTA score, reception of intratympanic steroid injections, tinnitus, dizziness, vertigo, diabetes, hypertension, and coronary artery disease. Commencing HBOT at an earlier stage is closely linked to greater improvements in hearing for patients with ISSNHL.

Functional molecule-mediated assembled copper nanozymes for diabetic wound healing

BACKGROUND

The complex hyperglycemic, hypoxic, and reactive oxygen species microenvironment of diabetic wound leads to vascular defects and bacterial growth and current treatment options are relatively limited by their poor efficacy.

RESULTS

Herein, a functional molecule-mediated copper ions co-assembled strategy was constructed for collaborative treatment of diabetic wounds. Firstly, a functional small molecule 2,5-dimercaptoterephthalic acid (DCA) which has symmetrical carboxyl and sulfhydryl structure, was selected for the first time to assisted co-assembly of copper ions to produce multifunctional nanozymes (Cu-DCA NZs). Secondly, the Cu-DCA NZs have excellent multicatalytic activity, and photothermal response under 808 nm irradiation. In vitro and in vivo experiments showed that it not only could efficiently inhibit bacterial growth though photothermal therapy, but also could catalyze the conversion of intracellular hydrogen peroxide to oxygen which relieves wound hypoxia and improving inflammatory accumulation. More importantly, the slow release of copper ions could accelerate cellular proliferation, migration and angiogenesis, synergistically promote the healing of diabetic wound furtherly.

CONCLUSIONS

The above results indicate that this multifunctional nanozymes Cu-DCA NZs may be a potential nanotherapeutic strategy for diabetic wound healing.

Potential of nanoemulsions for accelerated wound healing: innovative strategies

Wounds represent various significant health concerns for patients and also contribute major costs to healthcare systems. Wound healing comprises of overlapped and various coordinated steps such as homeostasis, inflammation, proliferation, and remodeling. In response to the failure of many strategies in delivering intended results including wound closure, fluid loss control, and exhibiting properties such as durability, targeted delivery, accelerated action, along with histocompatibility, numerous nanotechnological advances have been introduced. To understand the magnitude of wound therapy, this systematic and updated review discussing the effectiveness of nanoemulsions has been undertaken. This review portrays mechanisms associated with wound healing, factors for delayed wound healing, and various technologies utilized to treat wounds effectively. While many strategies are available, nanoemulsions have attracted the tremendous attention of scientists globally for the research in wound therapy due to their long-term thermodynamic stability and bioavailability. Nanoemulsions not only aid in tissue repair, but are also considered as an excellent delivery system for various synthetic and natural actives. Nanotechnology provides several pivotal benefits in wound healing, including improved skin permeation, controlled release, and stimulation of fibroblast cell proliferation. The significant role of nanoemulsions in improved wound healing along with their preparation techniques has also been highlighted with special emphasis on mechanistic insights. This article illustrates recent research advancements for the utilization of nanoemulsions in wound treatment. An adequate literature search has been conducted using the keywords 'Nanoemulsions in wound healing', 'Wound therapy and nanoemulsions', 'Herbal actives in wound therapy', 'Natural oils and wounds treatment' etc., from PubMed, Science Direct, and Google Scholar databases. Referred and original publications in the English language accessed till April 2022 has been included, whereas nonEnglish language papers, unpublished data, and nonoriginal papers were excluded from the study.

Oxygen Nanobubbles-Embedded Hydrogel as Wound Dressing to Accelerate Healing

Herein, we propose an oxygen nanobubbles-embedded hydrogel (ONB-G) with carbopol for oxygenation of wounds to accelerate the wound healing process. We integrate carbopol, hydrogel, and dextran-based oxygen nanobubbles (ONBs) to prepare ONB-G where ONBs can hold and release oxygen to accelerate wound healing. Oxygen release tests showed that the proposed ONB-G could encapsulate oxygen in the hydrogels for up to 34 days; meanwhile, fluorescence studies indicated that the ONB-G could maintain high oxygen levels for up to 4 weeks. The effect of carbopol concentration on the oxygen release capacity and rheological features of the ONB-G were also investigated along with the sterility of ONB-G. HDFa cell-based studies were first conducted to evaluate the viability, proliferation, and revival of cells in hypoxia. Scratch assay and mRNA expression studies indicated the potential benefit for wound closure. Histological evaluation of tissues with a pig model with incision and punch wounds showed that treatment with ONB-G exhibited improved healing compared with hydrogel without ONBs or treated without the gel. Our studies show that dextran-shell ONBs embedded in a gel (ONB-G) have the potential to accelerate wound healing, given its oxygen-holding capacity and release properties.

Functional carbohydrate-based hydrogels for diabetic wound therapy

Diabetes wound are grave and universal complications of diabetes. Owing to poor treatment course, high amputation rate and mortality, diabetes wound treatment and care have become a global challenge. Wound dressings have received much attention due to their ease of use, good therapeutic effect, and low costs. Among them, carbohydrate-based hydrogels with excellent biocompatibility are considered to be the best candidates for wound dressings. Based on this, we first systematically summarized the problems and healing mechanism of diabetes wounds. Next, common treatment methods and wound dressings were discussed, and the application of various carbohydrate-based hydrogels and their corresponding functionalization (antibacterial, antioxidant, autoxidation and bioactive substance delivery) in the treatment of diabetes wounds were emphatically introduced. Ultimately, the future development of carbohydrate-based hydrogel dressings was proposed. This review aims to provide a deeper understanding of wound treatment and theoretical support for the design of hydrogel dressings.

Microalgae share key features with human erythrocytes and can safely circulate through the vascular system in mice

As animal cells cannot produce oxygen, erythrocytes are responsible for gas interchange, being able to capture and deliver oxygen upon tissue request. Interestingly, several other cells in nature produce oxygen by photosynthesis, raising the question of whether they could circulate within the vascular networks, acting as an alternative source for oxygen delivery. To address this long-term goal, here some physical and mechanical features of the photosynthetic microalga Chlamydomona reinhardtii were studied and compared with erythrocytes, revealing that both exhibit similar size and rheological properties. Moreover, key biocompatibility aspects of the microalgae were evaluated in vitro and in vivo, showing that C. reinhardtii can be co-cultured with endothelial cells, without affecting each other's morphology and viability. Moreover, short-term systemic perfusion of the microalgae showed a thoroughly intravascular distribution in mice. Finally, the systemic injection of high numbers of microalgae did not trigger deleterious responses in living mice. Altogether, this work provides key scientific insights to support the notion that photosynthetic oxygenation could be achieved by circulating microalgae, representing another important step towards human photosynthesis. KEY POINTS: • C. reinhardtii and endothelial cells are biocompatible in vitro. • C. reinhardtii distribute throughout the entire vasculature after mice perfusion. • C. reinhardtii do not trigger deleterious responses after injection in mice.

The Role of Hyperbaric Oxygen Therapy in the Treatment of Surgical Site Infections: A Narrative Review

Surgical site infections (SSIs) are among the most prevalent postoperative complications, with significant morbidity and mortality worldwide. In the past half century, hyperbaric oxygen therapy (HBOT), the administration of 100% oxygen intermittently under a certain pressure, has been used as either a primary or alternative therapy for the management or treatment of chronic wounds and infections. This narrative review aims to gather information and evidence supporting the role of HBOT in the treatment of SSIs. We followed the Scale for the Quality Assessment of Narrative Review Articles (SANRA) guidelines and scrutinized the most relevant studies identified in Medline (via PubMed), Scopus, and Web of Science. Our review indicated that HBOT can result in rapid healing and epithelialization of various wounds and has potential beneficial effects in the treatment of SSIs or other similar infections following cardiac, neuromuscular scoliosis, coronary artery bypass, and urogenital surgeries. Moreover, it was a safe therapeutic procedure in most cases. The mechanisms related to the antimicrobial activity of HBOT include direct bactericidal effects through the formation of reactive oxygen species (ROS), the immunomodulatory effect of HBOT that increase the antimicrobial effects of the immune system, and the synergistic effects of HBOT with antibiotics. We emphasized the essential need for further studies, especially randomized clinical trials and longitudinal studies, to better standardize HBOT procedures as well as to determine its full benefits and possible side effects.

H2O2-PLA-(Alg)2Ca Hydrogel Enriched in Matrigel® Promotes Diabetic Wound Healing

Hydrogel-based dressings exhibit suitable features for successful wound healing, including flexibility, high water-vapor permeability and moisture retention, and exudate absorption capacity. Moreover, enriching the hydrogel matrix with additional therapeutic components has the potential to generate synergistic results. Thus, the present study centered on diabetic wound healing using a Matrigel-enriched alginate hydrogel embedded with polylactic acid (PLA) microspheres containing hydrogen peroxide (H2O2). The synthesis and physicochemical characterization of the samples, performed to evidence their compositional and microstructural features, swelling, and oxygen-entrapping capacity, were reported. For investigating the three-fold goal of the designed dressings (i.e., releasing oxygen at the wound site and maintaining a moist environment for faster healing, ensuring the absorption of a significant amount of exudate, and providing biocompatibility), in vivo biological tests on wounds of diabetic mice were approached. Evaluating multiple aspects during the healing process, the obtained composite material proved its efficiency for wound dressing applications by accelerating wound healing and promoting angiogenesis in diabetic skin injuries.

The Influence of Combined Physical Therapy Procedures on Oxygen Partial Pressure in Tissues Surrounding Ulcer in Patients With Venous Leg Ulcers

Venous ulcers in lower legs remain a profound treatment problem in contemporary medicine. Proper healing requires, among other things, sufficient blood supply and provision of suitable amount of oxygen to the treated tissues. The aim of the study was to assess the influence of combined physical therapy applied in patients with chronic venous leg ulcers on the oxygen partial pressure values. Fifty-four patients (25 females and 29 males), in the age range of 38 to 89 years with chronic venous leg ulcers, underwent a cycle of 15 procedures with the use of Laserobaria-S device. During a procedure, the patient's lower limb was simultaneously exposed to oxygen having the pressure of 1.5 ATA, low-frequency magnetic field, and low-energy light radiation. Before procedures, directly after the first procedure, as well as on completion of the entire therapeutic cycle, the patients underwent oxygen partial pressure measurements in the tissues surrounding the ulceration area, by means of transcutaneous oximetry, with the use of Medicap Précise 8008s device. The combined physical therapy shows a statistically significant increase of oxygen partial pressure values in tissues surrounding the ulceration, from the average of 68.63 ± 17.04 mm Hg before commencing the therapeutic cycle, to the average of 74.20 ± 18.92 mm Hg after the first procedure (P < .001) and to the average value of 83.79 ± 20.74 mm Hg (P < .001) after completion of therapeutic cycle. Combined physical therapy procedures cause a statistically significant increase of oxygen partial pressure values in tissues surrounding the ulceration, assessed using the objective method of transcutaneous oximetry, both in women and men.

Hyperbaric Oxygen Therapy in Plastic, Aesthetic, and Reconstructive Surgery: Systematic Review

Introduction: Hyperbaric oxygen therapy (HBOT) has been used over the past six decades to treat multiple conditions. This systematic review aims to identify and evaluate the clinical outcomes of hyperbaric oxygen therapy in the field of plastic, reconstructive, and aesthetic surgery, found in the literature from the year 2000 to the present. Methods: A systematic review of the literature focused on the conceptual and methodological aspects of the PRISMA Declaration. The search for clinical trials focused on the results of hyperbaric therapy in plastic, reconstructive, and cosmetic surgery. The Newcastle–Ottawa scale suggested by the Cochrane manual was applied to each study. The study was carried out with a defined protocol and was registered in PROSPERO, with code CRD42022301261. Results: From the 170 articles identified, 6 were selected. Five of them showed that hyperbaric oxygen therapy favored the reduction of the size of skin ulcers and increased the formation of granulation tissue (two trials; p < 0.05), increased the partial pressure of transcutaneous oxygen in patients with free flaps (one trial; p < 0.001), reduced perfusion in keloid scarring disorder (one trial; p < 0.01), and accelerated both the fading of melanin pigmentation and the decrease in age spot size (one trial; p < 0.05). The methodological quality was moderate in all cases because there was no blinding method reported. One study failed to find differences in flap survival, time to resolution of venous congestion, resolution of edema, and postoperative recovery period (p > 0.05). Conclusions: Hyperbaric oxygen therapy has been increasingly used in the field of plastic and reconstructive surgery, and has shown potential benefits in promoting wound healing, reducing the risk of infection, and improving the survival of tissues used in reconstructive procedures. Further research with more rigorous clinical trials is needed to fully understand the efficacy and optimal use of this therapy in the field of plastic and reconstructive surgery.

Photoresponsive polymeric microneedles: An innovative way to monitor and treat diseases

Microneedles (MN) technology is an emerging technology for the transdermal delivery of therapeutics. When combined with photoresponsive (PR) materials, MNs can deliver therapeutics precisely and effectively with enhanced efficacy or synergistic effects. This review systematically summarizes the therapeutic applications of PRMNs in cancer therapy, wound healing, diabetes treatment, and diagnostics. Different PR approaches to activate and control the release of therapeutic agents from MNs are also discussed. Overall, PRMNs are a powerful tool for stimuli-responsive controlled-release therapeutic delivery to treat various diseases.

Smart bioadhesives for wound healing and closure

The high demand for rapid wound healing has spurred the development of multifunctional and smart bioadhesives with strong bioadhesion, antibacterial effect, real-time sensing, wireless communication, and on-demand treatment capabilities. Bioadhesives with bio-inspired structures and chemicals have shown unprecedented adhesion strengths, as well as tunable optical, electrical, and bio-dissolvable properties. Accelerated wound healing has been achieved via directly released antibacterial and growth factors, material or drug-induced host immune responses, and delivery of curative cells. Most recently, the integration of biosensing and treatment modules with wireless units in a closed-loop system yielded smart bioadhesives, allowing real-time sensing of the physiological conditions (e.g., pH, temperature, uric acid, glucose, and cytokine) with iterative feedback for drastically enhanced, stage-specific wound healing by triggering drug delivery and treatment to avoid infection or prolonged inflammation. Despite rapid advances in the burgeoning field, challenges still exist in the design and fabrication of integrated systems, particularly for chronic wounds, presenting significant opportunities for the future development of next-generation smart materials and systems.

Diabetic Foot Complications: A Retrospective Cohort Study

Diabetes mellitus is a highly prevalent disease globally and contributes to significant morbidity and mortality. As a consequence of multiple pathophysiologic changes which are associated with diabetes, these patients frequently suffer from foot-related disorders: infections, ulcerations, and gangrene. Approximately half of all amputations occur in diabetic individuals, usually as a complication of diabetic foot ulcers. In this retrospective study, we analyzed and characterized a cohort of 69 patients and their diabetes-related foot complications. The main characteristics of our cohort were as follows: older age at diagnosis (mean age 66); higher incidence of diabetes in males; predominantly urban patient population. The most frequent complications of the lower extremity were ulcerations and gangrene. Moreover, in our study, 35% of patients required surgical reintervention, and 27% suffered from complications, while 13% required ICU admission. However, diabetic foot lesions are preventable via simple interventions which pointedly reduce foot amputations. Early identification and the appropriate medical and surgical treatment of the complications associated with diabetic foot disease are important because they still remain common, complex and costly.

Keeping an eye on the diabetic foot: The connection between diabetic eye disease and wound healing in the lower extremity

Diabetic eye disease is strongly associated with the development of diabetic foot ulcers (DFUs). DFUs are a common and significant complication of diabetes mellitus (DM) that arise from a combination of micro- and macrovascular compromise. Hyperglycemia and associated metabolic dysfunction in DM lead to impaired wound healing, immune dysregulation, peripheral vascular disease, and diabetic neuropathy that predisposes the lower extremities to repetitive injury and progressive tissue damage that may ultimately necessitate amputation. Diabetic retinopathy (DR) is caused by cumulative damage to the retinal mic-rovasculature from hyperglycemia and other diabetes-associated factors. The severity of DR is closely associated with the development of DFUs and the need for lower extremity revascularization procedures and/or amputation. Like the lower extremity, the eye may also suffer end-organ damage from macrovascular compromise in the form of cranial neuropathies that impair its motility, cause optic neuropathy, or result in partial or complete blindness. Additionally, poor perfusion of the eye can cause ischemic retinopathy leading to the development of proliferative diabetic retinopathy or neovascular glaucoma, both serious, vision-threatening conditions. Finally, diabetic corneal ulcers and DFUs share many aspects of impaired wound healing resulting from neurovascular, sensory, and immunologic compromise. Notably, alterations in serum biomarkers, such as hemoglobin A1c, ceruloplasmin, creatinine, low-density lipoprotein, and high-density lipoprotein, are associated with both DR and DFUs. Monitoring these parameters can aid in prognosticating long-term outcomes and shed light on shared pathogenic mechanisms that lead to end-organ damage. The frequent co-occurrence of diabetic eye and foot problems mandate that patients affected by either condition undergo reciprocal comprehensive eye and foot evaluations in addition to optimizing diabetes management.

Reduced Hospitalizations and Amputations in Patients with Diabetic Foot Ulcers Treated with Cyclical Pressurized Topical Wound Oxygen Therapy: Real-World Outcomes

Background: This study sought to examine the real-world impact of multimodality cyclical-pressure topical wound oxygen therapy (TWO2) on hospitalizations and amputations in patients with diabetic foot ulcer (DFU) compared with patients without TWO2. Methods: We conducted a retrospective review of deidentified patient medical records at 2 U.S. Veterans Affairs hospitals between January 2012 and January 2020. DFU patients were assigned to TWO2 or NO TWO2 cohorts based on their treatment records. Patients received appropriate standard of care and may have received other advanced wound treatments, including skin substitutes, negative pressure wound therapy, and growth factors. Primary study outcomes were patients requiring hospitalization and/or amputation within 360 days of initial wound documentation. Findings: Among unmatched cohorts of 202 patients with DFU (91 TWO2, 111 NO TWO2), 6.6% and 12.1% of TWO2 patients had hospitalizations and amputations, respectively, compared with 54.1% and 41.4% of NO TWO2 patients within 360 days (p < 0.0001, p < 0.0001), representing 88% and 71% reductions. Among propensity score-matched cohorts of 140 DFU patients (70 TWO2, 70 NO TWO2), compared with NO TWO2, 82% fewer TWO2 patients were hospitalized (7.1% vs. 40.0%, p < 0.0001) and 73% fewer TWO2 patients had amputations (8.6% vs. 31.4%, p = 0.0007). Logistic regression among matched cohorts demonstrated nearly ninefold and fivefold higher risk of hospitalization and amputation, respectively, for NO TWO2 versus TWO2. Interpretation: This retrospective cohort study demonstrates that treating patients with DFU with TWO2 is associated with significant reductions in hospitalizations and amputations in the real-world setting.

Efficacy and safety of topical oxygen therapy for diabetic foot ulcers: An updated systematic review and meta-analysis

To evaluate the efficacy and safety of topical oxygen therapy (TOT) in diabetic foot ulcers (DFUs), researchers systematically retrieved relevant studies from PubMed, EMBASE, Web of Science, CENTRAL and ClinicalTrials.gov. Relevant studies were searched from database inception to January 2022. Two researchers independently screened the literature, extracted data and assessed the quality of the included studies. Statistical analysis was performed in Stata 16.0. A total of seven RCTs involving 614 participants were included. Compared with the control group, the TOT group had a higher healing rate (RR = 1.63, 95% CI [1.33, 2.00]). According to descriptive analysis, TOT reduced the ulcer area and improved healing durability and quality of life. Furthermore, it had no effect on the occurrence of adverse events. However, it was unclear whether it would be able to reduce the healing time. The existing evidence suggests that TOT is effective and safe for chronic DFUs. Further studies are warranted to validate our findings.

Self-reinforcement hydrogel with sustainable oxygen-supply for enhanced cell ingrowth and potential tissue regeneration

Hydrogels composed of natural biopolymers are attractive for tissue regeneration applications owing to their advantages such as biocompatibility and ease of administration, etc.. Yet, the low oxygen level and the crosslinked network inside bulk hydrogels, as well as the hypoxic status in defect areas, hamper cell viability, function, and eventual tissue repair. Herein, based on Ca²⁺-crosslinked alginate hydrogel, oxygen-generating calcium peroxide (CaO₂) was introduced, which could provide a dynamic crosslinking alongside the CaO₂ decomposition. Compared to the CaCl₂-crosslinked alginate hydrogel, bone marrow mesenchymal stromal cells cultured with CaO₂-contained system displayed remarkably improved biological behaviors. Furthermore, in vivo evaluations were carried out on a subcutaneous implantation in rats, and the results demonstrated the importance of the local oxygen availability in a series of crucial events for tissue regeneration, such as activating cell viability, migration, angiogenesis, and osteogenesis. In summary, the obtained Ca²⁺-crosslinked alginate hydrogel achieved a better microenvironment for cell ingrowth and potential tissue regeneration as the CaCl₂ crosslinker being replaced by oxygen-generating CaO₂ nanoparticles, due to its contribution in remedying the local hypoxic condition, promisingly, the release of Ca²⁺ makes the hydrogel to be a possible candidate scaffold for bone tissue engineering.

Is combined physical therapy more effective than topical hyperbaric oxygen therapy in the treatment of venous leg ulcers? Preliminary study

Introduction

Recently, increased frequency of chronic leg ulcers has been observed. The aim of the study was to compare therapeutic efficacy of combined physical therapy to topical hyperbaric oxygen therapy in the treatment of venous leg ulcers.

Materials and Methods

Participants included 36 patients (14 females and 22 males) between 18 and 80 years of age with chronic venous leg ulcers. They were randomly divided into two study groups. Group I underwent topical hyperbaric oxygen therapy; group II underwent combined physical therapy. Before and after the therapeutic cycle (15 procedures) measurement of ulceration size by planimetry and analysis of laboratory parameters of blood was performed.

Results

In both groups, a statistically significant reduction of ulcer surface area was obtained (25.11±17.8cm2 to 16.93±13.89cm2, p=0.000196) vs. (34.17±14.82cm2 to 23.99±15.15cm2, p=0.004337). Blood morphology revealed a statistically significant reduction in patients from group II who underwent combined physical therapy (p=0.01). In both groups, statistically significant reduction of fibrinogen level (p=0.01 and p<0.001), and total protein level (p=0.01) was achieved. In group II reduction of the inflammation marker C-reactive protein (CRP) was noted.

Conclusions

Topical hyperbaric oxygen therapy and combined physical therapy had statistically significant effects on the reduction of surface area of treated venous leg ulcers. The changes in morphological and biochemical parameters may indicate the anti-inflammatory and anti-clotting action effects of combined physical therapy.

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...

A First in Human Trial Implanting Microalgae Shows Safety of Photosynthetic Therapy for the Effective Treatment of Full Thickness Skin Wounds

Insufficient oxygen supply represents a relevant issue in several fields of human physiology and medicine. It has been suggested that the implantation of photosynthetic cells can provide oxygen to tissues in the absence of a vascular supply. This approach has been demonstrated to be successful in several in vitro and in vivo models; however, no data is available about their safety in human patients. Here, an early phase-1 clinical trial (ClinicalTrials.gov identifier: NCT03960164, https://clinicaltrials.gov/ct2/show/NCT03960164) is presented to evaluate the safety and feasibility of implanting photosynthetic scaffolds for dermal regeneration in eight patients with full-thickness skin wounds. Overall, this trial shows that the presence of the photosynthetic microalgae Chlamydomonas reinhardtii in the implanted scaffolds did not trigger any deleterious local or systemic immune responses in a 90 days follow-up, allowing full tissue regeneration in humans. The results presented here represent the first attempt to treat patients with photosynthetic cells, supporting the translation of photosynthetic therapies into clinics.

Clinical Trial Registration:www.clinicaltrials.gov/ct2/show/NCT03960164, identifier: NCT03960164.

Nano-Silver Medical Antibacterial Dressing Combined with High-Flow Oxygen Therapy Facilitates Ulcer Wound Healing of Superficial Malignant Tumors

Background

Due to the poor healing of superficial malignant tumor ulcer wounds, patients suffer great pain and significantly reduced quality of life. Related research shows that oxygen therapy can reduce wound bleeding and promote wound healing.

Objective

This study aims to explore the therapeutic effect of nano-silver antibacterial dressing combined with high-flow oxygen therapy on surface malignant tumor ulcers.

Methods

In this retrospective analysis, 64 patients with superficial malignant tumors and ulcer infection were included and divided into the research group and the control group, with 32 cases in each group. After conventional debridement, the control group was treated with vaseline dressing, while the research group was treated with nano-silver medical antibacterial dressing combined with high-flow oxygen therapy. Both groups were treated for 7 days. The frequency of dressing change and the number of times of blood oozing between the two groups after treatment were recorded. The pain, clinical efficacy, and levels of procalcitonin (PCT) and C-reactive protein (CRP) were compared between the two groups before and after treatment.

Results

The dressing changes and blood oozing were less frequent in the research group compared with the control group. The pain score and the levels of PCT and CRP in the research group were lower than those in the control group. The overall response rate was significantly higher in the research group as compared to the control group. All the above differences were statistically significant (P<0.05).

Conclusion

Nano-silver medical antibacterial dressing combined with high-flow oxygen therapy can reduce the frequency of dressing changes in patients, relieve pain, reduce inflammation, and accelerate the healing of superficial malignant tumor ulcer wounds.

Enhancing wound healing dressing development through interdisciplinary collaboration

The process of wound healing includes four phases: Hemostasis, inflammation, proliferation, and remodeling. Many wound dressings and technologies have been developed to enhance the body's ability to close wounds and restore the function of damaged tissues. Several advancements in wound healing technology have resulted from innovative experiments by individual scientists or physicians working independently. The interplay between the medical and scientific research fields is vital to translating new discoveries in the lab to treatments at the bedside. Tracing the history of wound dressing development reveals that there is an opportunity for deeper collaboration between multiple disciplines to accelerate the advancement of novel wound healing technologies. In this review, we explore the different types of wound dressings and biomaterials used to treat wounds, and we investigate the role of multidisciplinary collaboration in the development of various wound management technologies to illustrate the benefit of direct collaboration between physicians and scientists.

Silica-supported near-infrared carbon dots and bicarbonate nanoplatform for triple synergistic sterilization and wound healing promotion therapy

Widespread bacterial infection and the emergence of antibiotic resistance exhibit an increasing threat to public health. Additionally, chronic wounds caused by bacterial infection have become a major challenge and threat in medical. Therefore, it is of great significance to explore effective and safe nanomaterials which possess antibacterial and wound healing promotion performance. Herein, we developed silica-supported near-infrared carbon dots (QPCuRC@MSiO₂) and bicarbonate (BC) nanoplatform (BC/QPCuRC@MSiO₂@PDA), which possess triple synergistic antibacterial including quaternary ammonium compounds (QACs), photothermal therapy (PTT), and photodynamic therapy (PDT). Meanwhile, the nanoplatform realized the controlled release of CO₂ in situ triggered by 808 nm laser irradiation for wound healing. In vitro and in vivo antibacterial assays displayed that the BC/QPCuRC@MSiO₂@PDA possess excellent antibacterial property, the antibacterial rate up to 99.6% and 99.99% to Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), respectively. Wound healing evaluation proved that suitable release of CO₂ could promote the process of infected wound healing, and the wound healing rate up to 100% after treatment for 14 days. Additionally, the cellular imaging experiment revealed that the BC/QPCuRC@MSiO₂@PDA could be considered as fluorescence probe. Together, these results demonstrated that the BC/QPCuRC@MSiO₂@PDA have great potential in biomedical field.

Dissolved oxygen technologies as a novel strategy for non-healing wounds: A critical review

Non-healing wounds are steadily becoming a global-health issue. Prolonged hypoxia propagates wound chronicity; yet, oxygenating treatments are considered inadequate to date. Dissolved oxygen (DO) in aqueous solutions introduces a novel approach to enhanced wound oxygenation, and is robustly evaluated for clinical applications. A systematic literature search was conducted, whereby experimental and clinical studies of DO technologies were categorized per engineering approach. Technical principles, methodology, endpoints and outcomes were analysed for both oxygenating and healing effects. Forty articles meeting our inclusion criteria were grouped as follows: DO solutions (17), oxygen (O₂ ) dressings (9), O₂ hydrogels (11) and O₂ emulsions (3). All technologies improved wound oxygenation, each to a variable degree. They also achieved at least one statistically significant outcome related to wound healing, mainly in epithelialization, angiogenesis and collagen synthesis. Scarcity in clinical data and methodological variability precluded quantitative comparisons among the biotechnologies studied. DO technologies warrantee further evaluation for wound oxygenation in the clinical setting. Standardised methodologies and targeted research questions are pivotal to facilitate global integration in healthcare.

A Pragmatic, Single-Center, Prospective, Randomized Controlled Trial of Adjunct Hemoglobin-Mediated Granulox Topical Oxygen Therapy Twice Weekly for Foot Ulcers

BACKGROUND

Achieving timely healing of foot ulcers can help avoid complications such as infection and amputation; topical oxygen therapy has shown promise in achieving this. We evaluated the clinical effectiveness of Granulox, a hemoglobin spray device designed to deliver oxygen to the surface of wounds, for the healing of foot ulcers.

METHODS

We conducted a single-center, prospective, randomized controlled trial comparing standard of care (once-weekly podiatric medical clinic visits) versus standard care plus adjunct Granulox therapy twice weekly in adults with foot ulcers. After a 2-week screening phase, patients in whom the index wound had healed by less than 50% were randomized 1:1. Outcome measures were collated during the trial phase at 6 and 12 weeks.

RESULTS

Of 79 patients enrolled, 38 were randomized. After 12 weeks, the median percentage wound size reduction compared with the size of the ulcer at the start of the trial phase was 100% for the control arm and 48% for the Granulox arm (P = .21, Mann-Whitney U test). In the former, eight of 14 foot ulcers had healed; in the latter, four of 15 (P = .14, Fisher exact test). In the control arm, two amputations and one withdrawal occurred, whereas in the Granulox arm, one unrelated death and five withdrawals were recorded.

CONCLUSIONS

We could not replicate the favorable healing associated with use of Granulox as published by others. Differences in wound chronicity and frequency of Granulox application might have influenced differences in study results. Granulox might perform best when used as an adjunct for treatment of chronic wounds at least 8 weeks old.

Topical Wound Oxygen Therapy in the Treatment of Chronic Diabetic Foot Ulcers

Oxygen is a critical component of many biological processes and is essential for wound healing. Chronic wounds are typically characterized as being hypoxic in that the partial pressure of oxygen (pO2) in the center of the wound is often below a critical threshold necessary to fully support those enzymatic processes necessary for tissue repair. Providing supplemental oxygen can effectively raise pO2 levels to better optimize functioning of these essential enzymes. While hyperbaric oxygen therapy has been well studied in this regard, comparative clinical studies have fallen short of providing clear evidence in support of this modality for healing chronic diabetic foot ulcers (DFU). Topical oxygen therapy (TOT) has been in clinical use for over 50 years with encouraging pre-clinical and clinical studies that have shown improved healing rates when compared to standard care. Nonetheless, TOT has heretofore been discounted as an unproven wound healing modality without theoretical or clinical evidence to support its use. This review shall provide a brief summary of the role of oxygen in wound healing and, specifically, discuss the different types of topical oxygen devices and associated studies that have convincingly shown their efficacy in healing chronic DFUs. The time has come for topical oxygen therapy to be embraced as a proven adjunctive modality in this regard.

Topical oxygen therapy for diabetes-related foot ulcers: A systematic review and meta-analysis

INTRODUCTION

Topical oxygen therapy (TOT) has been suggested as a treatment for diabetes-related foot ulcer (DFU) but no prior meta-analyses of randomised clinical trials (RCT) have been reported. This systematic review and meta-analysis examined the randomised evidence for the benefit of TOT in healing DFU.

METHODS

Publicly available databases were searched for RCTs investigating the effect of TOT on wound healing in participants with a DFU. The primary outcome was ulcer healing defined as full epithelialisation. Meta-analyses were performed using random effect models and reported as risk ratios (RR) and 95% confidence intervals (CI). Study quality and publication bias were assessed using a modified version of the Cochrane Collaboration's tool and funnel plots, respectively.

RESULTS

Six RCTs involving 530 participants with a DFU testing TOT were included. Meta-analysis suggested that TOT significantly increased the likelihood of ulcer healing compared to controls (Risk ratio [RR] 1.94; 95% CI 1.19, 3.17; I²  = 57%; NNT = 5.33) and findings were robust in sensitivity analyses. Risk of bias was high, moderate and low in two, one and three studies, respectively. Analysis of the three trials judged to be at low risk of bias suggested that TOT increased the likelihood of ulcer healing compared to controls (RR 2.37; 95% CI 1.52, 3.68; I²  = 0%). Funnel plots suggested the possibility of publication bias. Data on amputation were too limited for meta-analysis.

CONCLUSION

This meta-analysis suggests that TOT improves the likelihood of DFU healing; however, its effect on amputation and cost-effectiveness are unclear.

Thermal Effects of Topical Hyperbaric Oxygen Therapy in Hard-to-Heal Wounds-A Pilot Study

Clinical studies have been performed to evaluate the thermal response of topical hyperbaric oxygen therapy (THBOT) in patients suffering from hard-to-heal wounds diagnosed as venous leg ulcers located on their lower extremities. It was found that this therapy leads to a temperature decrease in areas around the wound. Moreover, a minor temperature differentiation between all areas was seen in the third period of topical hyperbaric oxygen therapy (THBOT) that may suggest that microcirculation and thermoregulation improvement start the healing process. On the other hand, the results of the conducted studies seem to prove that thermal imaging may provide a safe and effective method of analyzing wound healing of hard-to-heal wounds being treated with THBOT. This is the first study that tries to show the possibilities of a very new method by evaluating treatment of hard-to-heal wounds using thermal imaging, similar to the hyperbaric oxygen therapy effects evaluated by thermal imaging and described previously. However, the first clinical results showed a decrease in temperature due to the THBOT session and some qualitative similarities in the decrease in temperature differentiation between the studied areas and the temperature effects obtained due to hyperbaric oxygen therapy.

Hyperbaric Oxygen Therapy and A-PRF Pre-Treated Implants in Severe Periodontitis: A Case Report

Implantation is currently the best option for tooth replacement in periodontitis. Some major contraindications for the immediate implant are acute periodontitis and active infection. We present the case of a 51-year-old female patient with the highest grade and stage periodontitis treated with advanced platelet-rich fibrin-enriched zirconia implants and with hyperbaric oxygen therapy (HBOT). In particular, HBOT before and after implantation promoted bone regeneration and implant integration, also providing an antiseptic effect. After six months, the implants were well established and fully healed from periodontal disease within 14 months. Further research could confirm a new indication for HBOT in treating periodontitis and dental implantation.

Managing Diabetic Foot Ulcers: Pharmacotherapy for Wound Healing

Historically, there has been a scarcity of evidence-based topical therapy to hasten the healing of diabetic foot ulcers. But recently new evidence-based treatments have emerged from multicentre, randomised, controlled trials. This article highlights those trials, and describes the current pharmacological management of the diabetic foot ulcer and the advances that have been made in wound therapy to date. It provides an overview of topical and systemic pharmacotherapies in current use and those in development for future use in managing the diabetic foot. For each treatment, proposed mechanisms of action and evidence available to support their clinical use are presented. There is supporting randomised, controlled evidence for sucrose octasulfate in the treatment of neuro-ischaemic ulcers, and multi-layered patch of autologous leucocytes, platelets and fibrin in ulcers with or without ischaemia. There is also evidence for placentally derived products and for topical and systemic oxygen therapy in the healing of diabetic foot ulcers. Growth factors, bio-engineered tissues, stem cell therapy, gene therapy and peptide therapy also have some supporting evidence in the healing of diabetic foot ulcers. Nonsurgical debriding agents may be useful when the optimum approach of sharp debridement is not possible, and immunomodulators may be helpful for their antimicrobial effects, but robust data is still required to strengthen the case for general use. The review does not cover antimicrobials as their primary role are as anti-infectives and not in wound healing. The development of nanotechnology has created a means of prolonging the bioavailability of target molecules at the wound site, with the use of glass/hydrogel nanoparticles, polyethylene glycol and hyaluronic acid. Looking forward, novel therapies, including traction force-activated payloads, local delivery of short-interfering RNA and finally hydrogels incorporating bioactive agents or cells may provide possibilities for pharmacotherapy in the future.

Photosymbiosis for Biomedical Applications

Without the sustained provision of adequate levels of oxygen by the cardiovascular system, the tissues of higher animals are incapable of maintaining normal metabolic activity, and hence cannot survive. The consequence of this evolutionarily suboptimal design is that humans are dependent on cardiovascular perfusion, and therefore highly susceptible to alterations in its normal function. However, hope may be at hand. “Photosynthetic strategies,” based on the recognition that photosynthesis is the source of all oxygen, offer a revolutionary and promising solution to pathologies related to tissue hypoxia. These approaches, which have been under development over the past 20 years, seek to harness photosynthetic microorganisms as a local and controllable source of oxygen to circumvent the need for blood perfusion to sustain tissue survival. To date, their applications extend from the in vitro creation of artificial human tissues to the photosynthetic maintenance of oxygen-deprived organs both in vivo and ex vivo, while their potential use in other medical approaches has just begun to be explored. This review provides an overview of the state of the art of photosynthetic technologies and its innovative applications, as well as an expert assessment of the major challenges and how they can be addressed.

Hyperbaric Oxygen Therapy: Descriptive Review of the Technology and Current Application in Chronic Wounds

Hyperbaric oxygen therapy (HBOT) serves as "primary" or "adjunctive" therapy in a wide range of pathologies. It is considered the mainstay of management for potentially life-threatening conditions such as carbon monoxide poisoning, decompression illness, and gas embolisms. Moreover, HBOT has been utilized for decades as an adjunctive therapy in a variety of medical disciplines, including chronic wounds, which affect approximately 6.5 million Americans annually. In general, chronic wounds are characterized by hypoxia, impaired angiogenesis, and prolonged inflammation, all of which may theoretically be ameliorated by HBOT. Nonetheless, the cellular, biochemical, and physiological mechanisms by which HBOT achieves beneficial results in chronic wounds are not fully understood, and there remains significant skepticism regarding its efficacy. This review article provides a comprehensive overview of HBOT, and discusses its history, mechanisms of action, and its implications in management of chronic wounds. In particular, we discuss the current evidence regarding the use of HBOT in diabetic foot ulcers, while digging deeply into the roots of controversy surrounding its efficacy. We discuss how the paucity of high-quality research is a tremendous challenge, and offer future direction to address existing obstacles.

Systemic treatment for severe concentrated sulfuric acid burns in an adult male at high altitude: A case report

BACKGROUND

The aim of this study was to report a case of a patient who suffered from severe concentrated sulfuric acid burns while working at high altitude. This patient recovered after systemic treatment. We also provide a literature review for a better understanding of the disease.

CASE SUMMARY

A 30-year-old male, who was working in a local chemical plant in Xining (the Qinghai provincial capital, China) at an altitude of 2261 m, suffered from burns 85% TBSA (III° 70%TBSA, deep II° 15%TBSA) after a tank containing 80% concentration of sulfuric acid exploded. The patient immediately received a series of first aid treatments, as well as rigorous wound managements after admission, which included protection for the whole body and organs, prevention and treatment of eye burns, and the appropriate oxygen therapy. After 65 d of treatment, the burn wounds had completely healed, and the patient was transferred to another specialized hospital for further eye treatment. The first aid before admission and the emergency treatment of wounds following admission were appropriate. No severe complications of sepsis, severe renal insufficiency, septic costal chondritis, corneal perforation or other burns occurred during the treatment.

CONCLUSION

The main causes of concentrated sulfuric acid burns consisted of accidental burns at work, accidents in the outside, factitious injuries and improper laboratory operations. The clinical manifestations were mostly deep II° and III° burns, with a formation of brown-black, leather-like eschar on the wound surface and locally embolized dendrite-like vessels. The clear cause of the injury and typical clinical manifestations in this case made it easy to diagnosis. However, adult cases with severe concentrated sulfuric acid burns in high altitude areas are rare, so the successful treatment of this case is of great significance.

Therapeutic Effects of Hyperbaric Oxygen in the Process of Wound Healing

Chronic and non-healing wounds, especially diabetic foot ulcers and radiation injuries, imply remarkable morbidity with a significant effect on the quality of life and a high sanitary cost. The management of these wounds requires complex actions such as surgical debris, antibiotic treatment, dressings and even revascularization. These wounds are characterized by poor oxygen supply resulting in inadequate oxygenation of the affected tissue. The adjuvant treatment with hyperbaric oxygen therapy (HBOT) may increase tissue oxygenation favoring the healing of wounds which do not respond to the usual clinical care. The increase in the partial pressure of oxygen contributes to cover the energy demands necessary for the healing process and reduces the incidence of infections. Moreover, the increase in oxygen leads to the production of reactive species with hormetic activity, acting on signaling pathways that modulate the synthesis of inflammation mediators, antioxidants and growth factors which can contribute to the healing process. Studies performed with cell cultures and in animal models seem to demonstrate the beneficial effects of HBOT. However, clinical trials do not show such conclusive results; thus, additional randomized placebo-controlled studies are necessary to determine the real efficacy of HBOT and the mechanism of action for various types of wounds.

A Multinational, Multicenter, Randomized, Double-Blinded, Placebo-Controlled Trial to Evaluate the Efficacy of Cyclical Topical Wound Oxygen (TWO2) Therapy in the Treatment of Chronic Diabetic Foot Ulcers: The TWO2 Study

OBJECTIVE

Topical oxygen has been used for the treatment of chronic wounds for more than 50 years. Its effectiveness remains disputed due to the limited number of robust high-quality investigations. The aim of this study was to assess the efficacy of multimodality cyclical pressure Topical Wound Oxygen (TWO2) home care therapy in healing refractory diabetic foot ulcers (DFUs) that had failed to heal with standard of care (SOC) alone.

RESEARCH DESIGN AND METHODS

Patients with diabetes and chronic DFUs were randomized (double-blind) to either active TWO2 therapy or sham control therapy-both in addition to optimal SOC. The primary outcome was the percentage of ulcers in each group achieving 100% healing at 12 weeks. A group sequential design was used for the study with three predetermined analyses and hard stopping rules once 73, 146, and ultimately 220 patients completed the 12-week treatment phase.

RESULTS

At the first analysis point, the active TWO2 arm was found to be superior to the sham arm, with a closure rate of 41.7% compared with 13.5%. This difference in outcome produced an odds ratio (OR) of 4.57 (97.8% CI 1.19, 17.57), P = 0.010. After adjustment for University of Texas Classification (UTC) ulcer grade, the OR increased to 6.00 (97.8% CI 1.44, 24.93), P = 0.004. Cox proportional hazards modeling, also after adjustment for UTC grade, demonstrated >4.5 times the likelihood to heal DFUs over 12 weeks compared with the sham arm with a hazard ratio of 4.66 (97.8% CI 1.36, 15.98), P = 0.004. At 12 months postenrollment, 56% of active arm ulcers were closed compared with 27% of the sham arm ulcers (P = 0.013).

CONCLUSIONS

This sham-controlled, double-blind randomized controlled trial demonstrates that, at both 12 weeks and 12 months, adjunctive cyclical pressurized TWO2 therapy was superior in healing chronic DFUs compared with optimal SOC alone.