Wound Creation Research Articles

H2S-Eluting Hydrogels Promote In Vitro Angiogenesis and Augment In Vivo Ischemic Wound Revascularization

Ischemic wounds are frequently encountered in clinical practice and may be related to ischemia secondary to diabetes, peripheral artery disease and other chronic conditions. Angiogenesis is critical to the resolution of ischemia. Hydrogen sulfide (H2S) is now recognized as an important factor in this process. H2S donors NaHS and GYY4137 were incorporated into the photosensitive polymer hydrogel gelatin methacrylate and evaluated. Human umbilical vein endothelial cell (HUVEC) culture was used to quantify toxicity and angiogenesis. Sprague Dawley rats were subjected to ischemic myocutaneous flap wound creation with and without application of H2S-eluting hydrogels. Tissue perfusion during wound healing was quantified using laser speckle contrast imaging, and gene and protein expression for VEGF were evaluated. Vascular density was assessed by CD31 immunohistochemistry. Successful incorporation of sulfide compounds was confirmed by scanning electron microscopy with energy-dispersive X-ray analysis, and under physiologic conditions, detectable H2S was present for up to 14 days by high-performance liquid chromatography. HUVECs exposed to hydrogels did not demonstrate excess cytotoxicity or apoptosis. A two-fold increase in angiogenic tube formation was observed in HUVECs exposed to H2S-eluting hydrogels. Rat ischemic flap wounds demonstrated greater perfusion at 14 days, and there was greater vascularity of healed wounds compared to untreated animals. A nearly two-fold increase in VEGF mRNA and a four-fold increase in VEGF protein expression were present in wounds from treated animals. Local-regional administration of H2S represents a novel potential therapeutic strategy to promote angiogenesis and improve wound healing after tissue injury or as a result of ischemic disease.

Laboratory exploration of the use of ripasudil in descemetorhexis with a human ex vivo model

The aim of the study was to investigate the effect of ripasudil on corneal endothelial cell survival and migration after two types of descemetorhexis on a human ex vivo model. Eleven human corneoscleral buttons were incubated in either 50 ml organ culture medium containing 10 μM ripasudil or 50 μl dimethyl sulfoxide (DMSO), the vehicle in ripasudil for 2 days prior to wound creation then for 14 days after. The wound was created with either full trephination scoring or by shallow trephination plus manual peeling. At day 14, immunohistochemistry with vimentin and Na+/K+/ATPase markers was conducted. Tissues were assessed at day 3, 7 and 14 for morphology, cell migration, cell viability and cell density. Full trephination scoring created more damage on tissues compared to shallow trephination with full Descemet membrane peeling. In the full trephination scoring group, no differences in cell viability were noted when ripasudil and DMSO were compared. With the peeling method, Ripasudil could protect the endothelial cell death and maintain the morphology compared to the control. At day 14, no differences in the peripheral cell viability and density were found between ripasudil and DMSO, although the ripasudil group presented significantly increased central cell count and cell viability. Increased cell migration was noted with ripasudil and the initial cell morphology of those migrated cells was similar to that of fibroblasts. In conclusion, ex vivo modelling suggested that peeling resulted in less cell damage than scoring and ripasudil maintained better morphology and promoted migration. These effects might be via transformation of endothelial cells into a more motile spindle-like phenotype.

3D-printed tool for creating standardized burn wounds in ex vivo skin tissues

IntroductionThe development of biomaterials and medical devices for burn wound treatment necessitates thorough investigation through in vitro/ex vivo models before transitioning to animal studies. Establishing a standardized and high-throughput burn wound model in ex vivo skin presents a considerable challenge. Our objective was to address this challenge by developing a practical and cost-effective 3D-printed burn wound tool capable of uniformly inducing burns in 12 skin samples simultaneously. Material and methodsUtilizing Autodesk Inventor software, we designed a 3D model comprising a plate-base component (PBC) and a rod-base component (RBC). The design was exported as a Standard Triangulation Language (STL) file, processed through "Slicer" software to generate a G-code file tailored for 3D printing. ResultsThe Rod-Base component underwent iterative design modifications to optimize weight, airflow, and material consumption, resulting in a final design featuring a unique star shape for enhanced airflow. Simultaneously, the Plate-Base component design evolved to enable easy and secure plate placement, demonstrating compatibility with 12-well plates. The average production time for the model was 14.5 h, with a production cost of approximately $20 (USD), covering printing material and steel rods. ConclusionIn conclusion, this study provides valuable insights into the required equipment and software, empowering researchers to efficiently produce their accurate and cost-effective 3D-printed tool for controlled and reproducible burn wound creation in ex vivo viable skin tissues.

A novel, reverse-phase-shifting, thermoreversible foaming hydrogel containing antibiotics for the treatment of thermal burns in a swine model – A pilot study

BackgroundThis study compared a novel topical hydrogel burn dressing (CI-PRJ012) to standard of care (silver sulfadiazine) and to untreated control in a swine thermal burn model, to assess for wound healing properties both in the presence and absence of concomitant bacterial inoculation. MethodsEight equal burn wounds were created on six Yorkshire swine. Half the wounds were randomized to post-burn bacterial inoculation. Wounds were subsequently randomized to three treatments groups: no intervention, CI-PRJ012, or silver sulfadiazine cream. At study end, a blinded pathologist evaluated wounds for necrosis and bacterial colonization. ResultsWhen comparing CI-PRJ012 and silver sulfadiazine cream to no treatment, both agents significantly reduced the amount of necrosis and bacteria at 7 days after wound creation (p < 0.01, independently for both). Further, CI-PRJ012 was found to be significantly better than silver sulfadiazine (p < 0.02) in reducing bacterial colonization. For wound necrosis, no significant difference was found between silver sulfadiazine cream and CI-PRJ012 (p = 0.33). ConclusionsCI-PRJ012 decreases necrosis and bacterial colonization compared to no treatment in a swine model. CI-PRJ012 appeared to perform comparably to silver sulfadiazine. CI-PRJ012, which is easily removed with the application of room-temperature water, may provide clinical advantages over silver sulfadiazine.

Synergistic Interaction between Topical Application of Allicin and Quercetin Enhances Diabetic Wound Healing Via Inflammatory in Wistar Rats

Prolonged and excessive inflammatory processes at the wound site result in delayed healing of diabetic wounds. Allicin and quercetin have significantly inhibited tumor necrosis factor alpha (TNF-α) and increased levels of transforming growth factor beta (TGF-β) and vascular endothelial growth factor (VEGF) in rats. However, there is no known investigation on the combination of both compounds on TNF-α, TGF-β, and VEGF as a topical healing agent via inflammatory mechanisms. This study aims to determine the synergistic interaction between topical application of allicin and quercetin in enhancing diabetic wound healing via inflammatory in Wistar rats. A total of 45 male Wistar rats weighing 180-250 g were induced diabetes by a single intraperitoneal injection of streptozotocin (45 mg/kg bw). Diabetic rats underwent wound creation under anaesthesia and a square-shaped open excision wound was made with a full-thickness measurement of 1 cm × 1 cm on the right side of the rat's back. Rats were randomly allocated into group namely, vehicle control, allicin, quercetin, and a combination of allicin and quercetin which is applied topically once a day at a dose of 10 mg/mL for 7 days. Our finding showed that once daily topical application of allicin and quercetin, both independently and synergistically, increased levels of TGF-β and VEGF, as well as decreased levels of TNF-α of the rat diabetic wound model compared with the vehicle control group over 7th day. The synergistic effects of allicin and quercetin significantly enhanced diabetic wound healing via inflammation in rats, by suppressing inflammatory cytokines and stimulating growth factors hence offering a new window of an experimental study.

The Combination of Vascular Endothelial Growth Factor A (VEGF-A) and Fibroblast Growth Factor 1 (FGF1) Modified mRNA Improves Wound Healing in Diabetic Mice: An Ex Vivo and In Vivo Investigation.

Diabetic foot ulcers (DFU) pose a significant health risk in diabetic patients, with insufficient revascularization during wound healing being the primary cause. This study aimed to assess microvessel sprouting and wound healing capabilities using vascular endothelial growth factor (VEGF-A) and a modified fibroblast growth factor (FGF1). An ex vivo aortic ring rodent model and an in vivo wound healing model in diabetic mice were employed to evaluate the microvessel sprouting and wound healing capabilities of VEGF-A and a modified FGF1 both as monotherapies and in combination. The combination of VEGF-A and FGF1 demonstrated increased vascular sprouting in the ex vivo mouse aortic ring model, and topical administration of a combination of VEGF-A and FGF1 mRNAs formulated in lipid nanoparticles (LNPs) in mouse skin wounds promoted faster wound closure and increased neovascularization seven days post-surgical wound creation. RNA-sequencing analysis of skin samples at day three post-wound creation revealed a strong transcriptional response of the wound healing process, with the combined treatment showing significant enrichment of genes linked to skin growth. f-LNPs encapsulating VEGF-A and FGF1 mRNAs present a promising approach to improving the scarring process in DFU.

Features of metabolism in chronic wound remodelling

Background/Aim: The treatment of chronic wounds continues to be a pressing problem throughout the world. Healing occurs through some evolutionarily conserved biochemical pathways. The mechanisms of development of disorders of reparative regeneration are not fully understood. The work aimed to study the dynamics of changes in metabolic parameters during the healing of chronic wounds. Methods: Healthy Wistar rats were divided into two groups. The animals of the first group were intact. Chronic wounds were simulated for the animals of the second group. On days 7, 14 and 28 after wound creation, the animals were euthanised. Biochemical parameters such as glucose, total protein, albumin, cholesterol, urea, creatinine, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) were assessed in the blood serum of animals. Results: It was found that the maximum decrease in glucose and total protein levels in the blood serum of animals in the experimental groups compared to intact animals was observed 2 weeks after surgery: the glucose concentration in rats was 1.7 times lower (p &lt; 0.001). The level of albumin in the blood serum of experimental animals compared to intact animals was reduced by 1.5 times after 14 days (p &lt; 0.001) and by 1.2 times after 28 days (p &lt; 0.01). A week after surgery, the concentration of urea in the blood serum of experimental animals was 1.3 times higher (p &lt; 0.01) than in intact rats and by day 28 after surgery, the urea level was 1.4 times higher (p &lt; 0.001). The reduction in cholesterol and creatinine levels was not significant. An increase in AST, AST and ALP levels in the blood serum of experimental animals was shown. An increase in the blood serum of animals 7 days after surgery compared to the indicators of intact animals: ALP concentrations by 2.8 times (p &lt; 0.001) and ALT concentrations by 1.4 times (p &lt; 0.001) was established. The AST level significantly increased 14 days after surgery (p &lt; 0.05). Conclusions: The study of metabolic parameters allows monitoring of the state of the body during the healing process of wounds to correct treatment tactics.

Epigallocatechin-3-gallate promotes wound healing response in diabetic mice by activating keratinocytes and promoting re-epithelialization.

Type 2 diabetes (T2D) is a metabolic disorder that causes numerous complications including impaired wound healing and poses a significant challenge for the management of diabetic patients. Epigallocatechin-3-gallate (EGCG) is a natural polyphenol that exhibits anti-inflammatory and anti-oxidative benefits in skin wounds, however, the direct effect of EGCG on epidermal keratinocytes, the primary cells required for re-epithelialization in wound healing remains unknown. Our study aims to examine the underlying mechanisms of EGCG's ability to promote re-epithelialization and wound healing in T2D-induced wounds. Murine models of wound healing in T2D were established via feeding high-fat high-fructose diet (HFFD) and the creation of full-thickness wounds. Mice were administered daily with EGCG or vehicle to examine the wound healing response and underlying molecular mechanisms of EGCG's protective effects. Systemic administration of EGCG in T2D mice robustly accelerated the wound healing response following injury. EGCG induced nuclear translocation of nuclear factor erythroid 2-related factor 2 (NRF2) and promoted cytokeratin 16 (K16) expression to activate epidermal keratinocytes and robustly promoted re-epithelialization of wounds in diabetic mice. Further, EGCG demonstrated high binding affinity with Kelch-like ECH-associated protein 1 (KEAP1), thereby inhibiting KEAP1-mediated degradation of NRF2. Our findings provide important evidence that EGCG accelerates the wound healing response in diabetic mice by activating epidermal keratinocytes, thereby promoting re-epithelialization of wounds via K16/NRF2/KEAP1 signaling axis. These mechanistic insights into the protective effects of EGCG further suggest its therapeutic potential as a promising drug for treating chronic wounds in T2D.

Shikonin potentiates skin wound healing in Sprague-Dawley rats by stimulating fibroblast and endothelial cell proliferation and angiogenesis.

Shikonin, a major component of Lithospermum erythrorhizon, exerts anti-inflammatory and antibacterial effects and expedites wound healing. This study aims to evaluate the anti-inflammatory and antioxidant activities of shikonin in a Sprague-Dawley rat model and cell models using fibroblast and endothelial cells. The impact of shikonin on the activity of endothelial cells and fibroblasts was examined by cell counting kit 8 and wound-healing assays. A diabetic rat model was constructed, followed by wound creation for treatment with shikonin. Hematoxylin-eosin staining was used to assess pathological changes, and Masson's trichrome method to detect collagen deposition. Immunohistochemistry using antibodies against proliferating cell nuclear antigen and CD31 was conducted to detect proliferation and vascular density. Enzyme-linked immunosorbent assay and immunohistochemistry were carried out to assess pro-inflammatory and anti-inflammatory factor concentrations. Western blot and immunofluorescence were implemented to analyze oxidative stress-related protein expression. Shikonin induced the activity of both fibroblasts and endothelial cells. Shikonin treatment contributed to facilitated wound healing and higher healing rates in rats. It also resulted in faster lesion debulking in tissues, reduced inflammatory infiltration, increased collagen deposition, and enhanced angiogenesis. Detection of markers at the wounds showed that shikonin accelerated cell proliferation, enhanced tissue remodeling, and inhibited oxidative stress. Shikonin stimulates the proliferation and migration of fibroblasts and endothelial cells to promote angiogenesis and tissue remodeling, resulting in faster wound healing.

Effect of oxpecker’s interaction on wounds healing process in calves at Federal Uuniversity of Agriculture cattle production farm, Abeokuta Southwest Nigeria

This study investigated the role of oxpeckers in wound creation and healing in calves at the Cattle Production Venture of the Federal University of Agriculture, Abeokuta. Eleven calves with wounds out of twenty in the herd of 234 animals were randomly recruited for this study. Bates-Jensen wound assessment tool (BWAT) was used to assess the size, depth and edges of the wound, necrotic tissue type and tissue, exudate type and amount, skin colour surrounding wound, peripheral tissue edema and induration, granulation tissue and epithelialization to determine the severity. Descriptive statistics and ANOVA were used to analyse data obtained. Nine (81%) out of the 11 calves had more than one wounds. The score for all wounds decreased on day 15. The highest average score was 38.2 while the lowest was 17.8. The average score for each wound fell under wound status continuum. The highest percentage of reduction was 16.2% while the lowest was 0.9%. All wounds granulated at one stage or the other, except in one calf that did not throughout the study. Three calves had epithelialization above 75% on BWAT score of 2. At the termination of the study, 5 calves showed epithelialization of their wounds, 3 above 75% and 2 less than 50% while one wound did not epithelialize. In conclusion, wounds induced or exacerbated on calves by oxpeckers were under the status of continuum, and none neither regenerated nor degenerated. The activities of oxpeckers contributed to the delay in the wound healing process in the calves.

The antibiotic bead pouch - a useful technique for temporary soft tissue coverage, infection prevention and therapy in trauma surgery.

Soft tissue defects resulting from trauma and musculoskeletal infections can complicate surgical treatment. Appropriate temporary coverage of these defects is essential to achieve the best outcomes for necessary plastic soft tissue defect reconstruction. The antibiotic bead pouch technique is a reasonable surgical approach for managing temporary soft tissue defects following adequate surgical debridement. This technique involves the use of small diameter antibiotic-loaded bone cement beads to fill the dead space created by debridement. By applying antibiotics to the bone cement and covering the beads with an artificial skin graft, high local dosages of antibiotics can be achieved, resulting in the creation of a sterile wound that offers the best starting position for soft tissue and bone defect reconstruction. This narrative review describes the rationale for using this technique, including its advantages and disadvantages, as well as pearls and pitfalls associated with its use in daily practice. In addition, the article provides a comprehensive overview of the literature that has been published since the technique was introduced in surgical practice.

Flanged Sutureless Intrascleral Fixation of Dislocated Hard 1-Piece Polymethyl Methacrylate Intraocular Lenses.

To describe the vitreoretinal surgical technique and report the outcomes of our method of sutureless flanged intrascleral haptic fixation of dislocated 1-piece polymethyl methacrylate intraocular lenses with rigid haptics. Ciliary sulcus-based scleral tunnels were created by placing valved 27-gauge (g) trocar cannulas limbus parallel with conjunctival displacement. After complete vitrectomy, the rigid haptics were then externalized using 27g forceps. Cautery was then used to form flanges at the haptic tips. The haptics were then pushed back into the mouths of the scleral tunnels. Flanged intrascleral fixation was successfully achieved in eight eyes of seven patients. The average age at the time of surgery was 75 ± 13.7 years, with a mean follow-up of 17.9 ± 16.3 months (range 3-42 months). Intraocular lens dislocation/subluxation was the most common indication for surgery. All patients fully recovered to their potential acuity by their third postoperative visit. The most significant complication was erosion of one haptic in one patient, which was successfully managed without requiring intraocular lens exchange. There were no complications of subsequent dislocation, endophthalmitis, retinal detachment, or uveitis-glaucoma-hyphema syndrome. Flanged sutureless intrascleral fixation of dislocated 1-piece polymethyl methacrylate intraocular lenses with rigid haptics can be safely and successfully performed, avoiding the large wound creation accompanying intraocular lens exchange and the disadvantages of suture-based techniques.

Abstract 538: Local Hydrogen Sulfide Therapy Augments Angiogenesis And Ischemic Wound Healing

Introduction: Hydrogen sulfide (H 2 S) is an important signaling molecule in cellular O 2 sensing, wound healing and angiogenesis. Low H 2 S levels have been shown in diabetes and cardiovascular disease and H 2 S impairment may play a role in chronic non-healing ischemic wounds. H 2 S promotes angiogenesis in cell culture but in vivo data are lacking. We utilized a novel local H 2 S delivery method to investigate the effects of H 2 S therapy in rodents. Methods: Sprague Dawley rats (n=6-10/group) underwent dorsal myocutaneous ischemic flap wound creation under anesthesia. NaHS solution (100 μM) was delivered locally to the wound every 12 hours via implanted microtubing externalized and attached to a fluid delivery vest. Sham rats received saline solution while a third group received H 2 S blocker DL-propargylglycine (PAG). Laser speckle contrast images (LSCI) were recorded over 14 days. Flap tissue was collected for histologic analysis of tissue viability and degree of ischemic insult. Neovascularization was quantified by CD31 immunohistochemistry (IHC). VEGF protein expression was quantified by Western blot. Results: H 2 S treated flaps reperfused at a two-fold greater rate compared to sham and PAG treated flaps by LSCI (mean 12.9 flux/day vs. 6.9 flux/day, P=0.02). IHC mean microvascularity in sham flaps was 18 vessels/mm 2 compared to 47 vessels/mm 2 in H 2 S treated flaps (P=0.0092). Panniculus carnosis muscle thickness (408 μm vs. 234 μm) and myofibril count (56 vs. 38/100k μm 2 ) were preserved in H 2 S treated flaps (P=0.02, 0.04). H 2 S treatment upregulated VEGF while PAG was associated with decreased expression. Conclusion: H 2 S treated flaps have improved wound revascularization, tissue healing and angiogenic signaling. Blockade of H 2 S results in poor revascularization and decreased angiogenic protein expression. H 2 S pathways may play a critical role in the pathogenesis of impaired wound healing and could represent a potential therapeutic target for ischemic wounds.

Pink Gingiva is it the Needle or the Light!

Objectiv: Gingival depigmentation is an aesthetic periodontal procedure that is carried out to eliminate gingival hyperpigmentation. Numerous depigmentation modalities are used namely surgical scraping, gingival autograft, cryosurgery, electrosurgery, and lasers. Microneddling(MN) is a novel technique that is conservative involving the creation of micro wounds and has been tried for depigmentation. Material and Methods: A 23 yrs old female patient without any systemic conditions reported to the Outpatient Department of Periodontology, Krishnadevaraya College of dental sciences and Hospital, with the chief complaint of dark-colored gums. Depigmentation with micro needling was done in the lower anterior and laser in the upper anterior region. Result: There was a considerable reduction in the oral pigmentation scores (Dummett Oral Pigmentation Index) using both techniques in the first and the fourth week. The Visual Analogue Scale score showed lesser pain in the microneedling area. Conclusion: Depigmentation using microneedling and lasers is effective. Microneedling is a simple, economical, and viable option for the removal of gingival depigmentation.

Various effects of 11,12 EET rescue wound healing in a combined model of diabetes and ischemia

Chronic non healing wounds in diabetic patients still impose a major problem in modern medicine. Especially additional peripheral vascular disease complicates treatment success in these patients. Thus, we analyzed the effects of 11,12 epoxyeicosatrienoic acid (EET) in a combined model of hyperglycemia and ischemia in mice. Hyperglycemia was induced by Streptozotozin 2 weeks prior to wounding. 3 days before wound creation 2 of the 3 suppling vessels of the moue ear were cautherized for ischemia. Either 11,12 EET or solvent for control was applied. Wound closure as well as TNF-α, TGF-β, SDF-1α, VEGF, CD31, and Ki67 were measured. The wounds closed on day 14.4 ± 0.4 standard deviation (SD). 11,12 EET treatment enhanced healing to 9.8 ± 0.6 SD. TNF-α level was augmented on day 9 compared to control and receded on day 18. TGF-β seemed to be elevated all days observed after 11,12 EET treatment. SDF-1α was enhanced on day 6 and 9 by 11,12 EET, and VEGF on day 6 and 18 as well as CD13 on day 3, 6, and 18. 11,12 EET did not alter Ki67. 11,12 EET are able to rescue deteriorated wound healing in a combined model of hyperglycamia and ischemia by resolution of inflammation, augmentation of neovascularization and increasing expression of TGF-β as well as SDF-1α.

Патогенез инфицированной ожоговой раны у крыс

Burns are a severe and widespread type of injury and are accompanied by local and systemic complications, leading to disability and death. Infection is a major complication of burn injury because thermal burns can cause disturbances of humoral and cellular immunity, and necrotized tissue ceases to perform its normal barrier function, which leads to the development of infection caused by environmental opportunistic microorganisms and commensals, which limits the ability of the skin to heal. In addition, the scab of a burn wound is a nutrient-rich environment that is easily colonized by microorganisms. Gram-positive bacteria are the first colonizers of the wound bed because they make up the microflora of the skin microbiome. Burn wounds are most commonly associated with Staphylococcus aureus, which is capable of producing virulence factors that slow wound healing. The frequency of thermal injuries and their subsequent infection necessitates the creation of new therapeutic agents as well as the development and adaptation of relevant model systems for preclinical studies. A sufficient number of in vivo models have been developed to study the pathogenesis of burn injuries, as well as to conduct specific studies as part of preclinical studies of potential therapeutic agents. Rats are an adaptable model for reproducing infected burn wounds and evaluating their course. The aim of the study was to evaluate the pathogenesis of infected burns, allowing further use of this model pathology in the study of a wide range of potential antiseptic and anti-burn agents. The study successfully generated a model of infected skin burn in Wistar rats. Creation of burn wounds was carried out by contact method, the inducing damage temperature was 100 °C, Staphylococcus aureus ATCC 25923 was used as an infectious agent. Evaluation of the dynamics of the course of an infected burn wound was carried out according to the results of planimetric, microbiological, cytological and histological studies. The developed model of an infected skin burn in rats is relevant to study the pharmacological activity of antiseptic agents and local anti-burn agents with an antimicrobial component of the mechanism of action.

Effect of orodispersible hyaluronic acid film on palatal mucosa wound healing.

The objective of the study was to evaluate the healing effect of hyaluronic acid films on palatal wounds. After making 5-mm diameter palatal wounds, 72 rats were randomly assigned to three groups: control, hyaluronic acid gel, and hyaluronic acid film. The animals were sacrificed at 3, 7, and 21 days after the experiment. Clinical, histological, and RT-PCR analyses were performed. Human ex vivo oral mucosa models were used. Histological analysis and pan-cytokeratin staining were performed at 5 days after wound creation. In rat model, both gels and films showed favorable healing on Days 3 and 7 compared with healing in the control (p < 0.05). Film showed remarkable VEGF and α-SMA expression than did the others (p < 0.05). Immunohistochemical analysis showed that film exhibited significantly lower CD68 and greater α-SMA and vimentin expression levels than those in the others (p < 0.05). In human model, re-epithelialization rate of film group was significantly higher than that of the others. Complete epithelial regeneration was confirmed only in film group using pan-cytokeratin staining. Within the limits of this study, hyaluronic acid film outperformed gels in terms of palatal wound healing in both models.

Low-power laser in increasing doses improve wound healing process in rats.

Low-power laser has been studied and applied as an auxiliary tool in wound healing. However, as it is a therapy with several variables to be controlled, there is great difficulty in establishing protocols and comparing its efficacy. Therefore, the objective of this study was to evaluate the effects of the use of low-power laser in fixed and crescent doses in the healing of skin wounds in rats. Seventy-five male Wistar rats were divided into three groups: G1 with animals that did not receive laser radiation; G2 with animals treated with fixed dose of 3 J/cm2 laser; G3 with animals treated with laser in increasing doses of 1 J/cm2, 3 J/cm2, 5 J/cm2. Macroscopic and histological analysis were performed. The lowest intensity of PMN was observed in the irradiated groups and G3 had lower intensity of this infiltrate compared to G1 and G2 (p <0.05). On the seventh day of injury, PMN infiltrate decreased in all groups, especially in G3 (p<0.05). It was observed that G2 had more blood vessels than G1 and G3 after 7 days of wound creation (p ˂ 0.05). Collagen quantification showed that laser-treated groups have increased collagen deposition. Different responses in the wound healing process were observed comparing G2 and G3 groups. The fluence of 1J/cm2 presented better results in the anti-inflammatory action than 3 J/cm2, although G3 presented the greatest amount of total collagen after ten days of treatment.

OUR EXPERIENCE WITH PEC MAJOR FLAP FOR STERNOCLAVICULAR JOINT INFECTIONS

Sternoclavicular joint infections are uncommon but severe and complex condition usually in medically complex and compromised hosts. These infections are challenging to treat with risks of infection extending into the mediastinal structures and surgical drainage is often faced with problems of multiple unplanned returns to theatre, chronic non-healing wounds that turn into sinus and the risk of significant clinical escalation and death. Percutaneous aspirations or small incision drainage often provide inadequate drainage and failed control of infection, while open drainage and washout require multidisciplinary support, due to the close proximity of the mediastinal structures and the great vessels as well as failure to heal the wounds and creation of chronic wound or sinus.We present our series of 8 cases over 6 years where we used the plan of open debridement of the Sternoclavicular joint with medial end of clavicle excision to allow adequate drainage. The surgical incision was not closed primarily, and a suction vacuum dressing was applied until the infection was contained on clinical and laboratory parameters. After the infection was deemed contained, the surgical incision was closed by local muscle flap by transferring the medial upper sternal head of the Pectoralis Major muscle to fill in the sternoclavicular joint defect. This technique provided a consistent and reliable way to overcome the infection and have the wound definitively closed that required no secondary procedures after the flap surgery and no recurrence of infections so far.We suggest that open and adequate drainage of Sternoclavicular joint staged with vacuum dressing followed by pectoralis major local flap is a reliable technique for achieving control of infection and wound closure for these challenging infections.

Efficacy of Polydeoxyribonucleotide in Promoting the Healing of Diabetic Wounds in a Murine Model of Streptozotocin-Induced Diabetes: A Pilot Experiment.

We assessed the efficacy of polydeoxyribonucleotide (PDRN) in accelerating the healing of diabetic wounds in a murine model of streptozotocin (STZ)-induced diabetes. After the creation of diabetic wounds, the mice of the PDRN SC, PDRN IP and PBS groups received a subcutaneous, an intra-peritoneal injection of PDRN and a subcutaneous injection of PBS, respectively. After euthanasia, time-dependent changes in the wound diameter and histologic scores were measured and vascular endothelial growth factor (VEGF), transforming growth factor-β1 (TGF-β1) and collagen types I and III were assessed for their expression levels. The PDRN SC and the PDRN IP groups showed a significantly smaller diameter of diabetic wounds, significantly higher histologic scores, a significantly greater expression of VEGF, a significantly lower expression of TGF-β1 and a significantly greater expression of collagen types I and III as compared with the PBS group (p < 0.05 or 0.0001). In conclusion, PDRN might be effective in promoting the healing of diabetic wounds in a murine model of STZ-induced diabetes.