Therapeutic Effects of Hyperbaric Oxygen in the Process of Wound Healing

Advancements in diabetic foot ulcer research: Focus on mesenchymal stem cells and their exosomes

Diabetes represents a widely acknowledged global public health concern. Diabetic foot ulcer (DFU) stands as one of the most severe complications of diabetes, its occurrence imposing a substantial economic burden on patients, profoundly impacting their quality of life. Despite the deepening comprehension regarding the pathophysiology and cellular as well as molecular responses of DFU, the current therapeutic arsenal falls short of efficacy, failing to offer a comprehensive remedy for deep-seated chronic wounds and microvascular occlusions. Conventional treatments merely afford symptomatic alleviation or retard the disease's advancement, devoid of the capacity to effectuate further restitution of compromised vasculature and nerves. An escalating body of research underscores the prominence of mesenchymal stem cells (MSCs) owing to their paracrine attributes and anti-inflammatory prowess, rendering them a focal point in the realm of chronic wound healing. Presently, MSCs have been validated as a highly promising cellular therapeutic approach for DFU, capable of effectuating cellular repair, epithelialization, granulation tissue formation, and neovascularization by means of targeted differentiation, angiogenesis promotion, immunomodulation, and paracrine activities, thereby fostering wound healing. The secretome of MSCs comprises cytokines, growth factors, chemokines, alongside exosomes harboring mRNA, proteins, and microRNAs, possessing immunomodulatory and regenerative properties. The present study provides a systematic exposition on the etiology of DFU and elucidates the intricate molecular mechanisms and diverse functionalities of MSCs in the context of DFU treatment, thereby furnishing pioneering perspectives aimed at harnessing the therapeutic potential of MSCs for DFU management and advancing wound healing processes.

Advances in nucleic acid delivery strategies for diabetic wound therapy

In recent years, the prevalence of diabetic wounds has significantly increased, posing a substantial medical challenge due to their propensity for infection and delayed healing. These wounds not only increase mortality rates but also lead to amputations and severe mobility issues. To address this, advancements in bioactive molecules such as genes, growth factors, proteins, peptides, stem cells, and exosomes into targeted gene therapies have emerged as a preferred strategy among researchers. Additionally, the integration of photothermal therapy (PTT), nucleic acid, and gene therapy, along with 3D printing technology and the layer-by-layer (LBL) self-assembly approach, shows promise in diabetic wound treatment. Effective delivery of small interfering RNA (siRNA) relies on gene vectors. This review provides an in-depth exploration of the pathophysiological characteristics observed in diabetic wounds, encompassing diminished angiogenesis, heightened levels of reactive oxygen species, and impaired immune function. It further examines advancements in nucleic acid delivery, targeted gene therapy, advanced drug delivery systems, layer-by-layer (LBL) techniques, negative pressure wound therapy (NPWT), 3D printing, hyperbaric oxygen therapy, and ongoing clinical trials. Through the integration of recent research insights, this review presents innovative strategies aimed at augmenting the multifaceted management of diabetic wounds, thus paving the way for enhanced therapeutic outcomes in the future.

Unlocking the potential of flavonoid-infused drug delivery systems for diabetic wound healing with a mechanistic exploration

Diabetes is one of the common endocrine disorders generally characterized by elevated levels of blood sugar. It can originate either from the inability of the pancreas to synthesize insulin, which is considered as an autoimmune disorder, or the reduced production of insulin, considered as insulin resistivity. A wound can be defined as a condition of damage to living tissues including skin, mucous membrane and other organs as well. Wounds get complicated with respect to time based on specific processes like diabetes mellitus, obesity and immunocompromised conditions. Proper growth and functionality of the epidermis gets sustained due to impaired diabetic wound healing which shows a sign of dysregulated wound healing process. In comparison with synthetic medications, phytochemicals like flavonoids, tannins, alkaloids and glycosides have gained enormous importance relying on their distinct potential to heal diabetic wounds. Flavonoids are one of the most promising and important groups of natural compounds which can be used to treat acute as well as chronic wounds. Flavonoids show excellent properties due to the presence of hydroxyl groups in their chemical structure, which makes this class of compounds different from others. Based on the novel principles of nanotechnology via utilizing suitable drug delivery systems, the delivery of bioactive constituents from plant source amplifies the wound-healing mechanism, minimizes complexities and enhances bioavailability. Hence, the encapsulation and applicability of flavonoids with an emphasis on mechanistic route and wound-healing therapeutics have been highlighted in the subsequent study with focus on multiple drug delivery systems.

The Optimal Effective Dose of Adipose-Derived Stem Cell Exosomes in Wound Healing

INTRODUCTION

Although the effect of adipose-derived mesenchymal stem cell exosomes (ADSC-exos) on wound healing with different doses are shown in various studies, efficient and sufficient doses of ADSC-exos are still unknown. The study aimed to determine the optimal dose of ADSC-exos in wound healing.

METHODS

The 45 Sprague-Dawley rats were randomly divided into five groups, with seven animals in each. After dorsal circular defects were created, each wound was injected as follows: group 1: saline, group 2: 10 μg/mL of ADSC-exos, group 3: 100 μg/mL of ADSC-exos, group 4: 200 μg/mL of ADSC-exos, and group 5: 400 μg/mL of ADSC-exos. The effects of ADSC-exos on epithelization, angiogenesis, and collagen formation were analyzed macroscopically, histopathologically, and immunohistochemically on day 14.

RESULTS

A total of 200 μg/mL and 400 μg/mL ADSC-exos groups had higher epithelial tongue length, epithelial tongue area, and angiogenesis scores than the other groups. Although there was no statistical difference in fibrosis scores among groups, collagen fibers were becoming well-organized as the ADSC-exos doses increased. While the wound area was clinically smaller in the 200 μg/mL ADSC-exos group, there was no statistically significant difference among groups on day 14.

CONCLUSIONS

A total of 200 μg/mL of ADSC-exos was found to be the adequate and effective dose for re-epithelialization and angiogenesis in cutaneous wound healing. Moreover, the collagen density increased with a more regular pattern in the 200 μg/mL group, which can be important in scar regulation.

Gases and gas-releasing materials for the treatment of chronic diabetic wounds

Chronic non-healing wounds are a common consequence of skin ulceration in diabetic patients, with severe cases such as diabetic foot even leading to amputations. The interplay between pathological factors like hypoxia-ischemia, chronic inflammation, bacterial infection, impaired angiogenesis, and accumulation of advanced glycosylation end products (AGEs), resulting from the dysregulation of the immune microenvironment caused by hyperglycemia, establishes an unending cycle that hampers wound healing. However, there remains a dearth of sufficient and effective approaches to break this vicious cycle within the complex immune microenvironment. Consequently, numerous scholars have directed their research efforts towards addressing chronic diabetic wound repair. In recent years, gases including Oxygen (O2), Nitric oxide (NO), Hydrogen (H2), Hydrogen sulfide (H2S), Ozone (O3), Carbon monoxide (CO) and Nitrous oxide (N2O), along with gas-releasing materials associated with them have emerged as promising therapeutic solutions due to their ability to regulate angiogenesis, intracellular oxygenation levels, exhibit antibacterial and anti-inflammatory effects while effectively minimizing drug residue-induced damage and circumventing drug resistance issues. In this review, we discuss the latest advances in the mechanisms of action and treatment of these gases and related gas-releasing materials in diabetic wound repair. We hope that this review can provide different ideas for the future design and application of gas therapy for chronic diabetic wounds.

Plants as a cost-effective source for customizable photosynthetic wound dressings: A proof of concept study

Oxygen is essential for tissue regeneration, playing a crucial role in several processes, including cell metabolism and immune response. Therefore, the delivery of oxygen to wounds is an active field of research, and recent studies have highlighted the potential use of photosynthetic biomaterials as alternative oxygenation approach. However, while plants have traditionally been used to enhance tissue regeneration, their potential to produce and deliver local oxygen to wounds has not yet been explored. Hence, in this work we studied the oxygen-releasing capacity of Marchantia polymorpha explants, showing their capacity to release oxygen under different illumination settings and temperatures. Moreover, co-culture experiments revealed that the presence of these explants had no adverse effects on the viability and morphology of fibroblasts in vitro, nor on the viability of zebrafish larvae in vivo. Furthermore, oxygraphy assays demonstrate that these explants could fulfill the oxygen metabolic requirements of zebrafish larvae and freshly isolated skin biopsies ex vivo. Finally, the biocompatibility of explants was confirmed through a human skin irritation test conducted in healthy volunteers following the ISO-10993-10-2010. This proof-of-concept study provides valuable scientific insights, proposing the potential use of freshly isolated plants as biocompatible low-cost oxygen delivery systems for wound healing and tissue regeneration.

Exosome Therapy for a Nonhealing Scalp Wound Following Chemoradiation and Surgical Therapy

This case report describes the safety and utility of a noninvasive therapy, Purified Exosome Product (PEP), for poorly healing scalp wounds in the setting of prior chemoradiation and surgery. A man in his 60s with a history of high-grade angiosarcoma of the right temporoparietal scalp reconstruction had a 1-year history of 2 nonhealing scalp wounds after neoadjuvant chemotherapy followed by concurrent chemoradiation therapy, wide local excision, and latissimus dorsi free flap and split-thickness skin graft. The patient underwent débridement followed by 4 collagen (Bellafill)-PEP and 4 fibrin (Tisseel)-PEP applications during 7 months in 2022. Photographs of the area of exposed bone of the temporoparietal wound were measured and standardized by ImageJ open-source software. The frontal wound was not routinely measured and therefore was qualitatively assessed by reviewing photographs over time. The frontal wound completely healed, and the temporoparietal wound showed a 96% decrease in overall size. The patient had no adverse effects of treatment and continues to demonstrate ongoing healing. This case exhibits the safety and utility of topical PEP therapy for noninvasive treatment of poorly healing scalp wounds and offers the potential for an alternative treatment of patients who are poor candidates for additional surgical intervention.

Bioenergetics of simultaneous oxygen and nitrate respiration and nitric oxide production in a Pseudomonas aeruginosa agar colony biofilm

Pseudomonas aeruginosa is a biofilm forming pathogen commonly associated with infection of the cystic fibrosis (CF) lung, chronic wounds and indwelling medical devices. P. aeruginosa is a facultative aerobe that can use nitrate (NO3-) found in healthy and infected tissues and body fluids to generate energy through denitrification. Further, P. aeruginosa the expression of denitrification genes has been found in specimens from people with CF. The main aim of this study was to determine the relative energy contribution of oxygen (O2) respiration and denitrification in single Pseudomonas aeruginosa PAO1 biofilm colonies under different O2 concentrations to estimate the possible relative importance of these metabolic processes in the context of biofilm infections. We showed that the used strain PAO1 in biofilms denitrified with nitrous oxide (N2O), and not nitrogen (N2), as the end product in our incubations. From simultaneous O2 and N2O microprofiles measured with high spatial resolution by microsensors in agar colony biofilms under air, N2 and pure O2, the rates of aerobic respiration and denitrification were calculated and converted to ATP production rates. Denitrification occurred both in the oxic and anoxic zones, and became increasingly dominant with decreasing O2 concentrations. At O2 concentrations characteristic for tissues and wounds (20-60 μM), denitrification was responsible for 50% of the total energy conservation in the biofilm. In addition the formation of nitric oxide (NO), a precursor of N2O and an important regulator of many cellular processes, was strongly influenced by the local O2 concentrations. NO production was inhibited under pure O2, present under anoxia (∼1 μM) and remarkably high (up to 6 μM) under intermediate O2 levels, which can be found in infected tissues. Possible impacts of such NO levels on both the host and the biofilm bacteria are discussed.

Enhancing angiogenesis: Innovative drug delivery systems to facilitate diabetic wound healing

Diabetic wounds (DW) constitute a substantial burden on global healthcare owing to their widespread occurrence as a complication of diabetes. Angiogenesis, a crucial process, plays a pivotal role in tissue recovery by supplying essential oxygen and nutrients to the injury site. Unfortunately, in diabetes mellitus, various factors disrupt angiogenesis, hindering wound healing. While biomaterials designed to enhance angiogenesis hold promise for the treatment of DWs, there is an urgent need for more in-depth investigations to fully unlock their potential in clinical management. In this review, we explore the intricate mechanisms of angiogenesis that are crucial for DW recovery. We introduce a rational design for angiogenesis-enhancing drug delivery systems (DDS) and provide a comprehensive summary and discussion of diverse biomaterials that enhance angiogenesis for facilitating DW healing. Lastly, we address emerging challenges and prospects in angiogenesis-enhancing DDS for facilitating DW healing, aiming to offer a comprehensive understanding of this critical healthcare issue and potential solutions.

Hyperbaric Oxygen Therapy Adjuvant Chemotherapy and Radiotherapy through Inhibiting Stemness in Glioblastoma

Glioblastoma multiforme (GBM) is the most common and deadliest primary brain tumor in adults. Despite the advances in GBM treatment, outcomes remain poor, with a 2-year survival rate of less than 5%. Hyperbaric oxygen (HBO) therapy is an intermittent, high-concentration, short-term oxygen therapy used to increase cellular oxygen content. In this study, we evaluated the effects of HBO therapy, alone or combined with other treatment modalities, on GBM in vitro and in vivo. In the in vitro analysis, we used a 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay to assess the effects of HBO therapy alone, a colony formation assay to analyze the effects of HBO therapy combined with radiotherapy and with temozolomide (TMZ), and a neurosphere assay to assess GBM stemness. In the in vivo analysis, we used immunohistochemical staining and in vivo bioluminescence imaging to assess GBM stemness and the therapeutic effect of HBO therapy alone or combined with TMZ or radiotherapy, respectively. HBO therapy did not affect GBM cell viability, but it did reduce the analyzed tumors' ability to form cancer stem cells. In addition, HBO therapy increased GBM sensitivity to TMZ and radiotherapy both in vitro and in vivo. HBO therapy did not enhance tumor growth and exhibited adjuvant effects to chemotherapy and radiotherapy through inhibiting GBM stemness. In conclusion, HBO therapy shows promise as an adjuvant treatment for GBM by reducing cancer stem cell formation and enhancing sensitivity to chemotherapy and radiotherapy.

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.

Oxygen-releasing biomaterials for chronic wounds breathing: From theoretical mechanism to application prospect

Chronic wounds have always been considered as "gordian knots" in medicine, in which hypoxia plays a key role in blocking healing. To address this challenge, although tissue reoxygenation therapy based on hyperbaric oxygen therapy (HBOT) has been performed clinically for several years, the bench to bedside still urges the evolution of oxygen-loading and -releasing strategies with explicit benefits and consistent outcome. The combination of various oxygen carriers with biomaterials has gained momentum as an emerging therapeutic strategy in this field, exhibiting considerable application potential. This review gives an overview of the essential relationship between hypoxia and delayed wound healing. Further, detailed characteristics, preparation methods and applications of various oxygen-releasing biomaterials (ORBMs) will be elaborated, including hemoglobin, perfluorocarbon, peroxide, and oxygen-generating microorganisms, those biomaterials are applied to load, release or generate a vast of oxygen to relieve the hypoxemia and bring the subsequent cascade effect. The pioneering papers regarding to the ORBMs practice are presented and trends toward hybrid and more precise manipulation are summarized.

Hyperbaric Oxygen Therapy Reduces Oxidative Stress and Inflammation, and Increases Growth Factors Favouring the Healing Process of Diabetic Wounds

Hyperbaric oxygen therapy (HBOT) is the clinical application of oxygen at pressures higher than atmospheric pressure. HBOT has been effectively used to manage diverse clinical pathologies, such as non-healing diabetic ulcers. The aim of the present study was to analyse the effects of HBOT on the plasma oxidative and inflammation biomarkers and growth factors in patients with chronic diabetic wounds. The participants received 20 HBOT sessions (five sessions/week), and blood samples were obtained at sessions 1, 5 and 20, before and 2 h after the HBOT. An additional (control) blood sample was collected 28 days after wound recovery. No significant differences were evident in haematological parameters, whereas the biochemical parameters progressively decreased, which was significant for creatine phosphokinase (CPK) and aspartate aminotransferase (AST). The pro-inflammatory mediators, tumour necrosis factor alpha (TNF-α) and interleukin 1β (IL-1β), progressively decreased throughout the treatments. Biomarkers of oxidative stress--plasma protein levels of catalase, extracellular superoxide dismutase, myeloperoxidase, xanthine oxidase, malondialdehyde (MDA) levels and protein carbonyls--were reduced in accordance with wound healing. Plasma levels of growth factors--platelet-derived growth factor (PDFG), transforming growth factor β (TGF-β) and hypoxia-inducible factor 1-alpha (HIF-1α)-- were increased as a consequence of HBOT and reduced 28 days after complete wound healing, whereas matrix metallopeptidase 9 (MMP9) progressively decreased with the HBOT. In conclusion, HBOT reduced oxidative and pro-inflammatory mediators, and may participate in activating healing, angiogenesis and vascular tone regulation by increasing the release of growth factors.

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.

Function and mechanism of mesenchymal stem cells in the healing of diabetic foot wounds

Diabetes has become a global public health problem. Diabetic foot is one of the most severe complications of diabetes, which often places a heavy economic burden on patients and seriously affects their quality of life. The current conventional treatment for the diabetic foot can only relieve the symptoms or delay the progression of the disease but cannot repair damaged blood vessels and nerves. An increasing number of studies have shown that mesenchymal stem cells (MSCs) can promote angiogenesis and re-epithelialization, participate in immune regulation, reduce inflammation, and finally repair diabetic foot ulcer (DFU), rendering it an effective means of treating diabetic foot disease. Currently, stem cells used in the treatment of diabetic foot are divided into two categories: autologous and allogeneic. They are mainly derived from the bone marrow, umbilical cord, adipose tissue, and placenta. MSCs from different sources have similar characteristics and subtle differences. Mastering their features to better select and use MSCs is the premise of improving the therapeutic effect of DFU. This article reviews the types and characteristics of MSCs and their molecular mechanisms and functions in treating DFU to provide innovative ideas for using MSCs to treat diabetic foot and promote wound healing.

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.

Advanced Drug Delivery System for Management of Chronic Diabetes Wound Healing

The diabetic wound is excessively vulnerable to infection because the diabetic wound suggests delayed and incomplete healing techniques. Presently, wounds and ulcers related to diabetes have additionally increased the medical burden. A diabetic wound can impair mobility, lead to amputations, or even death. In recent times, advanced drug delivery systems have emerged as promising approaches for enhancing the efficacy of wound healing treatments in diabetic patients. This review aims to provide an overview of the current advancements in drug delivery systems in managing chronic diabetic wound healing. This review begins by discussing the pathophysiological features of diabetic wounds, including impaired angiogenesis, elevated reactive oxygen species, and compromised immune response. These factors contribute to delayed wound healing and increased susceptibility to infection. The importance of early intervention and effective wound management strategies is emphasized. Various types of advanced drug delivery systems are then explored, including nanoparticles, hydrogels, transferosomes, liposomes, niosomes, dendrimers, and nanosuspension with incorporated bioactive agents and biological macromolecules are also utilized for chronic diabetes wound management. These systems offer advantages such as sustained release of therapeutic agents, improved targeting and penetration, and enhanced wound closure. Additionally, the review highlights the potential of novel approaches such as antibiotics, minerals, vitamins, growth factors gene therapy, and stem cell-based therapy in diabetic wound healing. The outcome of advanced drug delivery systems holds immense potential in managing chronic diabetic wound healing. They offer innovative approaches for delivering therapeutic agents, improving wound closure, and addressing the specific pathophysiological characteristics of diabetic wounds.

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.

Microenvironment-Based Diabetic Foot Ulcer Nanomedicine

Diabetic foot ulcers (DFU), one of the most serious complications of diabetes, are essentially chronic, nonhealing wounds caused by diabetic neuropathy, vascular disease, and bacterial infection. Given its pathogenesis, the DFU microenvironment is rather complicated and characterized by hyperglycemia, ischemia, hypoxia, hyperinflammation, and persistent infection. However, the current clinical therapies for DFU are dissatisfactory, which drives researchers to turn attention to advanced nanotechnology to address DFU therapeutic bottlenecks. In the last decade, a large number of multifunctional nanosystems based on the microenvironment of DFU have been developed with positive effects in DFU therapy, forming a novel concept of "DFU nanomedicine". However, a systematic overview of DFU nanomedicine is still unavailable in the literature. This review summarizes the microenvironmental characteristics of DFU, presents the main progress of wound healing, and summaries the state-of-the-art therapeutic strategies for DFU. Furthermore, the main challenges and future perspectives in this field are discussed and prospected, aiming to fuel and foster the development of DFU nanomedicines successfully.

Tissue healing changes on wounds in rats after treatment with Hancornia speciosa latex in cream-gel formulation

PURPOSE

Hancornia speciosa latex has shown pharmacological potential in wound healing processes due to its angiogenic, osteogenic, and anti-inflammatory activities. The aims of this study were to carry out a cream-gel formulation with 5, 10 and 25% of H. speciosa serum latex and to evaluate its potential to stimulate the skin regeneration in rats' wounds.

METHODS

One hundred and twenty rats were divided into five groups: neutral control with saline (G1), cream-gel based on H. speciosa latex serum at 5% m/v (G2), cream-gel at 15% m/v (G3), cream-gel at 25% m/v (G4), and cream-gel (G5). The animals were euthanized at three, seven, 14 and 21 days after the injury induction, and some parameters were analyzed: wound contraction, necrosis, fibrin, polymorphonuclear and mononuclear infiltrates, fibroblast, angiogenesis, hemorrhage, and collagen.

RESULTS

The therapeutic treatment with cream-gel at 15 and 25% is beneficial in the inflammatory phase of healing processes since it increased the angiogenesis and proliferation of mononuclear infiltrations in wounds. Regarding wound contraction, the treatment with cream-gel (5 and 15%) induced a higher rate of contraction in the proliferative phase. The 15% cream-gel formulation stimulated a greater production of collagen in the injured tissues.

CONCLUSIONS

H. speciosa cream-gel is a low-cost herbal medicine which can aid in tissue repair.

Cellular Therapeutics for Chronic Wound Healing: Future for Regenerative Medicine

Chronic wounds are associated with significant morbidity and mortality, which demand long-term effective treatment and represent a tremendous financial strain on the global healthcare systems. Regenerative medicines using stem cells have recently become apparent as a promising approach and are an active zone of investigation. They hold the potential to differentiate into specific types of cells and thus possess self-renewable, regenerative, and immune-modulatory effects. Furthermore, with the rise of technology, various cell therapies and cell types such as Bone Marrow and Adipose-derived Mesenchymal Cell (ADMSC), Endothelial Progenitor Cells (EPCs), Embryonic Stem Cells (ESCs), Mesenchymal Stem Cell (MSCs), and Pluripotent Stem Cells (PSCs) are studied for their therapeutic impact on reparative processes and tissue regeneration. Cell therapy has proven to have substantial control over enhancing the quality and rate of skin regeneration and wound restoration. The literature review brings to light the mechanics of wound healing, abnormalities resulting in chronic wounds, and the obstacles wound care researchers face, thus exploring the multitude of opportunities for potential improvement. Also, the review is focused on providing particulars on the possible cell-derived therapeutic choices and their associated challenges in healing, in the context of clinical trials, as solutions to these challenges will provide fresh and better future opportunities for improved study design and therefore yield a substantial amount of data for the development of more specialized treatments.

Therapeutic targets and signaling mechanisms of dasatinib activity against radiation skin ulcer

Objective

To reveal the potential targets and signaling pathways of dasatinib in the treatment of radiation ulcers through network pharmacology and molecular docking technology.

Methods

Pathological targets of radiation ulcers were screened using GeneCards database. At the same time, the pharmacological targets of dasatinib were obtained through SwissTargetPrediction (STP), Binding DB and Drugbank databases. Subsequently, the potential targets of dasatinib for anti-radiation ulcers were obtained after intersection by Venn diagram. Next, a protein-protein interaction (PPI) network was constructed through the STRING database and core targets were screened. Finally, the identified core targets were subjected to GO and KEGG enrichment analysis, co-expression network analysis, and molecular docking technology to verify the reliability of the core targets.

Results

A total of 76 potential targets for anti-radiation ulcer with dasatinib were obtained, and 6 core targets were screened, including EGFR, ERBB2, FYN, JAK2, KIT, and SRC. These genes were mainly enriched in Adherens junction, EGFR tyrosine kinase inhibitor resistance, Focal adhesion, Bladder cancer and PI3K-Akt signaling pathway. Molecular docking results showed that dasatinib binds well to the core target.

Conclusion

Dasatinib may play a role in the treatment of radiation ulcers by regulating EGFR, ERBB2, FYN, JAK2, KIT, and SRC. These core targets may provide new insights for follow-up studies of radiation ulcers.

Application of Whole-Body Hyperbaric Oxygen Therapy in the Treatment of Grade III Exposed Dog Bite Wounds

Objective. The aim of the study is to evaluate the therapeutic effect of hyperbaric oxygen in the treatment of grade III exposed dog bite wounds. Method. Fifty-two patients with grade III dog bite wounds who were seen in the emergency department of our hospital from 2017 to 2021 were selected for this research. The participants were randomly divided into an experimental group and a control group, with 26 patients in each group. The experimental group received hyperbaric oxygen therapy (HBOT), and the control group received routine treatment. The patients were followed up for three months after the treatment concluded. The wound healing rate, infection rate, and healing time were measured and compared. Results. The cure rate of the experimental group (96.2%) was higher than that of the control group (69.2%). The infection rate in the experimental group (3.8%) was lower than that of the control group (30.8%). The average cure time of the experimental group (9 ± 2.7) was lower than that of the control group (11 ± 3.4). The number of dressing changes in the experimental group (4 ± 3.0) was lower than that of the control group (7.5 ± 3.5), and there was a significant difference between the two groups ( $P<0.05$ ). Conclusion. According to the results, HBOT of grade III dog bite wounds can promote wound healing, improve the cure, and reduce the wound infection rate. It should have a primary role in the clinical treatment of these wounds.

Complexed Polymer Film-Forming Spray: An Optimal Delivery System for Secretome of Mesenchymal Stem Cell as Diabetic Wound Dressing?

Diabetes-related wounds have physiological factors that make healing more complicated. High sugar levels can increase microbial infection risk while limiting nutrition and oxygen transfer to the wound area. The secretome of mesenchymal stem cells has been widely known for its efficacy in regenerative therapy. However, applying the secretome directly to the wound can reduce its effectiveness. In this review, we examined the literature on synthesizing the combinations of carboxymethyl chitosan, hyaluronic acid, and collagen tripeptides, as well as the possibility of physicochemical properties enhancement of the hydrogel matrix, which could potentially be used as an optimal delivery system of stem cell's secretome for diabetic wound healing.

Medical Gas Therapy for Tissue, Organ, and CNS Protection: A Systematic Review of Effects, Mechanisms, and Challenges

Gaseous molecules have been increasingly explored for therapeutic development. Here, following an analytical background introduction, a systematic review of medical gas research is presented, focusing on tissue protections, mechanisms, data tangibility, and translational challenges. The pharmacological efficacies of carbon monoxide (CO) and xenon (Xe) are further examined with emphasis on intracellular messengers associated with cytoprotection and functional improvement for the CNS, heart, retina, liver, kidneys, lungs, etc. Overall, the outcome supports the hypothesis that readily deliverable "biological gas" (CO, H2 , H2 S, NO, O2 , O3 , and N2 O) or "noble gas" (He, Ar, and Xe) treatment may preserve cells against common pathologies by regulating oxidative, inflammatory, apoptotic, survival, and/or repair processes. Specifically, CO, in safe dosages, elicits neurorestoration via igniting sGC/cGMP/MAPK signaling and crosstalk between HO-CO, HIF-1α/VEGF, and NOS pathways. Xe rescues neurons through NMDA antagonism and PI3K/Akt/HIF-1α/ERK activation. Primary findings also reveal that the need to utilize cutting-edge molecular and genetic tactics to validate mechanistic targets and optimize outcome consistency remains urgent; the number of neurotherapeutic investigations is limited, without published results from large in vivo models. Lastly, the broad-spectrum, concurrent multimodal homeostatic actions of medical gases may represent a novel pharmaceutical approach to treating critical organ failure and neurotrauma.

Theaflavin Attenuates TBHP-Induced Endothelial Cells Oxidative Stress by Activating PI3K/AKT/Nrf2 and Accelerates Wound Healing in Rats

The treatment of wounds remains a clinical challenge because of poor angiogenesis under the wound bed, and increasingly, the patients’ need for functional and aesthetically pleasing scars. Previous reports have shown that Theaflavin can induce angiogenesis and terminate the progression of ischemic cardiovascular disease, but limited therapy is available for the management of cutaneous wounds. In this study, our in vitro work discovered that human umbilical vein endothelial cells (HUVECs) exposed to Theaflavin can alleviate apoptosis and cell dysfunction induced by tert-butyl hydroperoxide (TBHP). The cellular activity of HUVECs were assessed by cell tube formation, migration and adhesion. Mechanistically, Theaflavin protected HUVECs from TBHP-stimulated cell apoptosis through the activation of the phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT)/nuclear factor (erythroid-derived 2)-like 2 (Nrf2) axis, so Nrf2 silencing can partly eliminate the cytoprotective effect of Theaflavin treatment. In in vivo experiments, administering Theaflavin orally can enhance vascularization in regenerated tissues and accelerate wound healing. In summary, our data served as a novel evidence for the wound healing treatment with Theaflavin, and certified the potential mechanism of Theaflavin, which can be used as a potential agent for cutaneous wound therapy.

Ultrasonic Intelligent Diagnosis of Papillary Thyroid Carcinoma Based on Machine Learning

Thyroid diseases are divided into papillary carcinoma and nodular diseases, which are very harmful to the human body. Ultrasound is a common diagnostic method for thyroid diseases. In the process of diagnosis, doctors need to observe the characteristics of ultrasound images, combined with professional knowledge and clinical experience, to give the disease situation of patients. However, different doctors have different clinical experience and professional backgrounds, and the diagnosis results lack objectivity and consistency, so an intelligent diagnosis technology for thyroid diseases based on the ultrasound image is needed in clinic, which can give objective and reliable diagnosis opinions on thyroid diseases by extracting the texture, shape, and other information of the image and assist doctors in clinical diagnosis. This paper mainly studies the intelligent ultrasonic diagnosis of papillary thyroid cancer based on machine learning, compares the ultrasonic characteristics of PTMC diagnosed by using the new ultrasound technology (CEUS and UE), and summarizes the differential diagnosis effect and clinical application value of the two technology methods for PTMC. In this paper, machine learning, diffuse thyroid image features, and RBM learning methods are used to study the ultrasonic intelligent diagnosis of papillary thyroid cancer based on machine learning. At the same time, the new contrast-enhanced ultrasound (CEUS) technology and ultrasound elastography (UE) technology are used to obtain the experimental phenomena in the experiment of ultrasonic intelligent diagnosis of papillary thyroid cancer. The results showed that 90% of the cases were diagnosed by contrast-enhanced ultrasound and confirmed by postoperative pathology. CEUS and UE have reliable practical value in the diagnosis of PTMC, and the combined application of CEUS and UE can improve the sensitivity and accuracy of PTMC diagnosis.

Prevention Effects of Chain Management on Pressure Ulcers of Hospitalized Patients

The study focused on the preventive effects of the chain management model on pressure ulcers in the operating room. Sqoop big data collection module is used to collect patient information from various hospital information systems in a distributed manner. The data were from the clinical data center of the Zhongshan Hospital Xiamen University General Hospital, and 268 patients were selected as the research subjects. A chain management model is constructed, concerning the preventive measures, the management of each link, the perioperative pressure ulcer management, and the reporting of pressure ulcers. Then, the two groups were compared for the SAS and SDS scores before and after nursing, the pressure ulcer sites, pressure ulcer reporting rate, pressure ulcer staging, and nursing satisfaction. The results show that it is not that more collection modules will lead to better cluster performance and that the execution delay is caused by MapReduce requiring the JAVA virtual machine, and after reaching a certain point, the increase in the number of tasks will slow down the process, and as data size increases, DataNote has an expanded capability to analyze data. After nursing treatment, the SAS and SDS scores of the two groups of patients were significantly lower than before treatment (P < 0.05). The pressure ulcers were mainly distributed in the forehead, mandible, cheeks, front chest, and knees in the two groups, and the difference between the two groups was statistically significant (P < 0.05). The total satisfaction of the observation group was 93.28%, and the total satisfaction of the control group was 92.54%. The patients' satisfaction with the chain management model was higher than that of conventional nursing.

Integrated analysis of tRNA-derived small RNAs reveals new therapeutic genes of hyperbaric oxygen in diabetic foot ulcers

Background: To reveal the alterations of tRNA-derived small RNA (tsRNA) expression profiles induced by hyperbaric oxygen (HBO) treatment in diabetic foot ulcers (DFUs) and investigate new therapeutic targets. Materials & methods: tsRNA sequencing was employed in normal skin tissue, in DFUs, and after HBO treatment groups. A quantitative real-time PCR was used to validate tsRNA sequencing results and their targets levels. Bioinformatics analysis was performed to reveal their therapeutic functions in DFUs. Results: A total of 22 tsRNAs were differentially expressed in the three groups. Three selected tsRNAs were validated by quantitative real-time PCR for further analysis, which were all significantly overexpressed in DFU while being normally expressed after HBO treatment. Bioinformatics analysis disclosed that these tsRNAs may play therapeutic roles through the regulation of the Wnt signaling pathway. Conclusion: tsRNAs may be novel useful targets for HBO to treat DFUs.

Systematic review with meta-analysis: effectiveness of hyperbaric oxygenation therapy for ulcerative colitis

BACKGROUND AND AIMS

Hyperbaric oxygenation therapy has been used in the treatment of ulcerative colitis in the past few years. However, its efficacy still remains unclear. The aim of the study was to investigate the efficacy of hyperbaric oxygen combination therapy in patients with ulcerative colitis.

METHODS

We conducted a comprehensive study search up to September 2020, from the online databases Embase, PubMed, Cochrane Library, China National Knowledge Infrastructure, WanFang and VIP.

RESULTS

Thirteen studies comprising 780 patients were included. We found that compared with conventional therapy, hyperbaric oxygen combination therapy was superior in reaching clinical remission [risk ratio (RR)=1.62; 95% confidence interval (CI) 1.42 to 1.84; p < 0.001] and clinical response (RR=1.29; 95% CI 1.21 to 1.38; p < 0.001), with lower disease activity scores [standard mean difference (SMD)= -1.19; 95%CI -1.74 to -0.65; p < 0.001]. An obvious reduction of serum levels of tumor necrosis factor-α (SMD= -1.96; 95%CI -2.50 to -1.41; p < 0.001) and interleukin (IL)-6 (SMD= -2.49; 95% CI -2.84 to -2.15; p < 0.001), and elevation of IL-10 level (SMD=2.40; 95% CI 0.68 to 4.12; p = 0.006) were also observed.

CONCLUSION

Hyperbaric oxygen combination therapy was effective in patients with ulcerative colitis, and has potential as a complementary method for its treatment.

Lower Extremity Ulcers

Lower extremity ulcerations contribute to significant morbidity and economic burden globally. Chronic wounds, or those that do not progress through healing in a timely manner, are estimated to affect 6.5 million people in the United States alone causing, significant morbidity and economic burden of at least an estimated $25 billion annually. Owing to the aging population and increasing rates of obesity and diabetes mellitus globally, chronic lower extremity ulcers are predicted to increase. Here, we explore the pathophysiology, diagnosis, and management of the most (and least) commonly seen lower extremity ulcers.

A Review of the Application of Hyperbaric Oxygen Therapy in Alzheimer's Disease

Alzheimer's disease (AD) is considered as the most common cause of dementia in elderly population. While the exact mechanism of AD has not been discovered, hyperbolic oxygen therapy (HBOT) has been proven to be effective in the treatment of this degenerative disease. The objectives of this article are to review the literature available on molecular and physiological mechanisms underlying HBOT and its efficacy in treating AD and to review the effectiveness of HBOT as an alternate treatment intervention in both human and animal models. 391 full text articles were included in the review after literature search between 1980-2021 from two online data base (ScienceDirect and PubMed). The following key words were used: 'hyperbaric oxygen therapy' and 'Alzheimer disease.' Based on the outcomes of clinical and experimental studies, this review advocates the use of HBOT for the treatment of AD. This review explores future directions and recommends further research into a treatment protocol that will maintain long-term cognitive health of AD patients.

Comparative Evaluation of Different Chitosan Species and Derivatives as Candidate Biomaterials for Oxygen-Loaded Nanodroplet Formulations to Treat Chronic Wounds

Persistent hypoxia is a main clinical feature of chronic wounds. Intriguingly, oxygen-loaded nanodroplets (OLNDs), filled with oxygen-solving 2H,3H-decafluoropentane and shelled with polysaccharides, have been proposed as a promising tool to counteract hypoxia by releasing a clinically relevant oxygen amount in a time-sustained manner. Here, four different types of chitosan (low or medium weight (LW or MW), glycol-(G-), and methylglycol-(MG-) chitosan) were compared as candidate biopolymers for shell manufacturing. The aim of the work was to design OLND formulations with optimized physico-chemical characteristics, efficacy in oxygen release, and biocompatibility. All OLND formulations displayed spherical morphology, cationic surfaces, ≤500 nm diameters (with LW chitosan-shelled OLNDs being the smallest), high stability, good oxygen encapsulation efficiency, and prolonged oxygen release kinetics. Upon cellular internalization, LW, MW, and G-chitosan-shelled nanodroplets did not significantly affect the viability, health, or metabolic activity of human keratinocytes (HaCaT cell line). On the contrary, MG-chitosan-shelled nanodroplets showed very poor biocompatibility. Combining the physico-chemical and the biological results obtained, LW chitosan emerges as the best candidate biopolymer for future OLND application as a skin device to treat chronic wounds.

Hyperbaric Oxygen Therapy: An Effective Auxiliary Treatment Method for Large Jaw Cysts

Background: To evaluate hyperbaric oxygen therapy (HBOT) on infection rates and repair rates during the treatment of large jaw cysts. Methods: A prospective randomized, non-blinded, controlled clinical trial included 90 patients with jaw cysts, randomly divided into three groups. Patients were treated with enucleations and bone substitute was used in the experimental and control groups. The experimental group received HBOT. The primary predictor variable was HBOT. The infection rate, repair rate, preoperative volume of the jaw cysts, age, and sex were statistically analyzed. The Fisher exact test was used to compare the infection rate and postoperative complications. The repair rate of the bone defects was analyzed using the repeated-measures analysis of variance and the least significant difference tests. The Kendall's coefficient of concordance and Kappa statistics were calculated to evaluate the consistency between the two investigators. Results: The infection rate was 3.4% in the experimental group, 14.3% in the blank group, and 32.1% in the control group (P<0.05). The repair rate in the experimental group was significantly higher than in the control and blank groups at 1, 3 and 6 months after surgery (P<0.05). Conclusion: The results showed that HBOT reduced the postoperative infection rate following the enucleation of large jaw cysts with bone substitute filling, and it also improved the bone repair rate.

Hyperbaric Oxygen Ameliorated Acute Pancreatitis in Rats via the Mitochondrial Pathway

BACKGROUND

Acute pancreatitis (AP) is a common disease of the digestive system. The mechanism of hyperbaric oxygen (HBO) therapy for AP is not completely clear.

AIMS

This study investigated the effects of HBO in AP and whether it acts through the mitochondria-mediated apoptosis pathway.

METHODS

Eighty male Sprague-Dawley rats were randomly assigned to four groups: control (8 rats), sham (24 rats), AP (24 rats), or AP + HBO (24 rats). AP was induced by ligating the pancreatic duct. The AP + HBO group was given HBO therapy starting at 6 h postinduction. Eight rats in each group were killed on days 1, 2, and 3 postinduction to assess pancreatic injury, mitochondrial membrane potential, ATP level, and expression levels of BAX, Bcl-2, caspase-3, caspase-9, and PARP in pancreatic tissue and blood levels of amylase, lipase, and pro-inflammatory cytokines.

RESULTS

HBO therapy alleviated the severity of AP and decreased histopathological scores and levels of serum amylase, lipase, and pro-inflammatory cytokines. Compared to AP induction alone, HBO therapy increased expression of the apoptotic protein BAX, caspase-3, caspase-9, and PARP and ATP levels in tissues and decreased antiapoptotic protein Bcl-2 expression levels and the mitochondrial membrane potential on the first day; the results on the second day were partly consistent with those on the first day, while there was no obvious difference on the third day.

CONCLUSIONS

HBO therapy could induce caspase-dependent apoptosis in AP rats to alleviate pancreatitis, which was possibly triggered by mitochondrial apoptosis pathway regulation of Bcl-2 family members.

Systematic review of the efficacy of topical haemoglobin therapy for wound healing

Hypoxia is a common cause of poor wound healing, for which a variety of oxygen therapies have been developed. In order to overcome the limitations of traditional methods of treatment, namely the type of equipment, its setting, safety and cost, local haemoglobin therapy has been developed, although no reviews have so far been published. Here, we systematically review the current evidence to establish the efficacy, scope, adverse reactions, and required precautions of this new form of therapy. A search of the literature was conducted in the PubMed, Embase, Scopus, CENTRAL, CINAHL, and Web of science databases, with 17 studies meeting the eligibility criteria, comprising one animal model study and 16 clinical studies. Local haemoglobin therapy is able to safely and effectively promote the healing of a variety of wounds, especially those that are chronic and non-healing. However, premature discontinuation of this treatment can result in impediment to wound healing and even deterioration of the wound. The distinct benefit of the elimination of slough and relief of pain suggests that this technique may represent a new generation of debridement technology. Furthermore, its ease of use and convenience enables patient self-management, thereby greatly reducing health care costs.

Integrin-mediated adhesive properties of neutrophils are reduced by hyperbaric oxygen therapy in patients with chronic non-healing wound

In recent years, several studies suggested that the ability of hyperbaric oxygen therapy (HBOT) to promote healing in patients with diabetic ulcers and chronic wounds is due to the reduction of inflammatory cytokines and to a significant decrease in neutrophils recruitment to the damaged area. α4 and β2 integrins are receptors mediating the neutrophil adhesion to the endothelium and the comprehension of the effects of hyperbaric oxygenation on their expression and functions in neutrophils could be of great importance for the design of novel therapeutic protocols focused on anti-inflammatory agents. In this study, the α4 and β2 integrins' expression and functions have been evaluated in human primary neutrophils obtained from patients with chronic non-healing wounds and undergoing a prolonged HBOT (150 kPa per 90 minutes). The effect of a peptidomimetic α4β1 integrin antagonist has been also analyzed under these conditions. A statistically significant decrease (68%) in β2 integrin expression on neutrophils was observed during the treatment with HBO and maintained one month after the last treatment, while α4 integrin levels remained unchanged. However, cell adhesion function of both neutrophilic integrins α4β1 and β2 was significantly reduced 70 and 67%, respectively), but α4β1 integrin was still sensitive to antagonist inhibition in the presence of fibronectin, suggesting that a combined therapy between HBOT and integrin antagonists could have greater antinflammatory efficacy.

Pharmacological activation of Nrf2 promotes wound healing

Wound repair and regeneration is a complex orchestrated process, comprising several phases interconnecting various cellular events and triggering multiple intracellular molecular pathways in damaged cells and tissues. In several metabolic disorders including diabetes mellitus, delay in wound healing due to elevated levels of cellular stress poses a key challenge. Several therapeutic wound dressing materials and strategies including hyperbaric oxygen therapy and negative pressure wound therapy have been developed to accelerate repair and restore cellular homeostasis at the wound site. Further, tremendous progress has been made in identification of transcriptional regulators involved in the process of wound healing. Nuclear factor erythroid 2-related factor 2 (Nrf2), a redox sensitive transcription factor, is the key regulator of intracellular redox homeostasis which induces the expression of cytoprotective genes and increases the production of antioxidants that scavenge free radicals. Activators of Nrf2 have been reported to combat oxidative stress and enhance the process of wound healing in several pathophysiological conditions, including diabetes and its complications such as diabetic foot ulcer, and chronic kidney disease, and diabetic nephropathy. Several bioactive compounds have been reported to reduce cellular stress, and thus accelerate cell proliferation, neovascularization results in repairing damaged tissues by the activation of the transcription factor, Nrf2. This review is focused on the strategies for diabetic wound healing and the highlights the role of bioactive compounds that activate the Nrf2 signaling and revitalize the cellular and molecular mechanism in the chronic wound niche, regulate and restore redox homeostasis thereby promoting wound repair and regeneration.

Hyberbaric oxygen and bone reconstruction

INTRODUCTION

The aim of this literature review was to determine the benefits of hyperbaric oxygen therapy after bone reconstruction procedures in humans and identify information that may be useful for the development of optimal protocols for hyperbaric oxygen therapy to stimulate bone healing.

EVIDENCE ACQUISITION

We searched the electronic database PubMed/Medline for studies published between January 1999 and December 2018, using the key words: "bone" or "bone graft" and "mandible reconstruction" or "jaw reconstruction" and "hyperbaric oxygen" or "HBO." First, the titles and abstracts of the studies found were evaluated and those that corresponded to the aims of this review were pre-selected for analysis of the full text. Subsequently, the full texts were analyzed, and those that met the eligibility criteria were pre-selected for the review. The full texts of studies whose abstracts did not provide enough data for decision were also evaluated. Two examiners independently assessed eligibility, risk of bias and extracted data.

EVIDENCE SYNTHESIS

A total of 2237 studies were found according to pre-established criteria for data collection, of which only 5 studies were included in this systematic review. Although we observed positive results in the included studies, there are still few standardized clinical studies in the literature, assessing hyperbaric oxygen therapy after extensive bone reconstructive procedures.

CONCLUSIONS

It is difficult to compare results found in different studies due to the variety of methodological and clinical conditions assessed.

Predictive factors of outcome of selective retina therapy for diabetic macular edema

PURPOSE

To investigate the predictive factors of clinical outcome of selective retina therapy (SRT) for diabetic macular edema (DME).

METHODS

This retrospective study included 22 eyes of 22 patients (15 males and 7 females), who were treated with SRT for DME at the Department of Ophthalmology of Osaka City University Hospital and observed at least 6 months after the treatment. The mean age was 64 years (range 40-81). Thirteen of the 22 eyes (59%) had a treatment history other than SRT before. SRT laser (527 nm, 1.7 µs, 100 Hz) was used for treatment. Changes in the best-corrected visual acuity (BCVA) (logMAR) and central macular thickness (CMT) in optical coherence tomography were examined at baseline, 3-month follow-up, and 6-month follow-up. Factors associated with the rate of change in CMT at 3 and 6 months after SRT were examined.

RESULTS

The mean BCVA (logMAR) was 0.26 ± 0.31, 0.22 ± 0.27 and 0.23 ± 0.29 at baseline, 3 months and 6 months, respectively (p = 0.15 at 3 months, 0.40 at 6 months; compared to baseline). The mean CMT was 502 ± 163, 493 ± 204, and 416 ± 185 μm at baseline, 3 months, and 6 months, respectively (p = 0.69 at 3 months, 0.01 at 6 months; compared to baseline). The multivariate analysis found a significant negative association with previous macular photocoagulation (p = 0.03) at 3 months and a positive association with a history of insulin use (p = 0.02) and previous panretinal photocoagulation (p = 0.03) at 6 months after SRT.

CONCLUSION

The CMT was significantly decreased at 6 months after SRT in DME. The history of insulin use and panretinal photocoagulation may positively and the history of macular photocoagulation may negatively affect the outcome of SRT, which must be considered when determining the therapeutic indications for SRT.

Oxidative Stress Markers to Investigate the Effects of Hyperoxia in Anesthesia

Oxygen (O₂) is commonly used in clinical practice to prevent or treat hypoxia, but if used in excess (hyperoxia), it may act as toxic. O₂ toxicity arises from the enhanced formation of Reactive Oxygen Species (ROS) that exceed the antioxidant defenses and generate oxidative stress. In this study, we aimed at assessing whether an elevated fraction of inspired oxygen (FiO₂) during and after general anesthesia may contribute to the unbalancing of the pro-oxidant/antioxidant equilibrium. We measured five oxidative stress biomarkers in blood samples from patients undergoing elective abdominal surgery, randomly assigned to FiO₂ = 0.40 vs. 0.80: hydroperoxides, antioxidants, nitrates and nitrites (NO_x), malondialdehyde (MDA), and glutathionyl hemoglobin (HbSSG). The MDA concentration was significantly higher 24 h after surgery, and the body antioxidant defense lower, in the FiO₂ = 0.80 group with respect to both the FiO₂ = 0.40 group and the baseline values (p ≤ 0.05, Student’s t-test). HbSSG in red blood cells was also higher in the FiO₂ = 0.80 group at the end of the surgery. NO_x was higher in the FiO₂ = 0.80 group than the FiO₂ = 0.40 group at t = 2 h after surgery. MDA, the main end product of the peroxidation of polyunsaturated fatty acids directly influenced by FiO₂, may represent the best marker to assess the pro-oxidant/antioxidant equilibrium after surgery.