Factors affecting wound healing

Gelatin Microgel Incorporated Poly(ethylene glycol)-Based Bioadhesive with Enhanced Adhesive Property and Bioactivity

Up to 7.5 wt % of chemically cross-linked gelatin microgel was incorporated into dopamine-modified poly(ethylene glycol) (PEGDM) adhesive to simultaneously improve the material property and bioactivity of the PEG-based bioadhesive. Incorporation of gelatin microgel reduced cure time while it increased the elastic modulus and cross-linking density of the adhesive network. Most notably, the loss modulus values for microgel-containing adhesive were an order of magnitude higher when compared to microgel-free control. This drastic increase in the viscous dissipation ability of the adhesive is attributed to the introduction of reversible physical bonds into the adhesive network with the incorporation of the gelatin microgel. Additionally, incorporation of the microgel increased the adhesive properties of PEGDM by 1.5- to 2-fold. From in vitro cell culture studies, the composite adhesive is noncytotoxic and the incorporation of microgels provided binding site for promoting fibroblast attachment and viability. The subcutaneous implantation study indicated that the microgel-containing PEGDM adhesive is biocompatible and the incorporated microgels provided pockets for rapid cellular infiltration. Gelatin microgel incorporation was demonstrated to be a facile method to simultaneously enhance the adhesive property and the bioactivity of PEG-based adhesive.

Managing burn wounds with SMARTPORE Technology polyurethane foam: two case reports

Background

Successful wound healing depends on various factors, including exudate control, prevention of microbial contaminants, and moisture balance. We report two cases of managing burn wounds with SMARTPORE Technology polyurethane foam dressing.

Case presentation

In Case 1, a 2-year-old Asian girl presented with a delayed (11 days) wound on her right leg. She sustained a thermal injury from a hot iron that was left idle on the floor. Clinical inspection revealed an infected wound with overlying eschar that traversed her knee joint. As her parents refused surgical debridement under general anesthesia, hydrotherapy and wound dressing using SMARTPORE Technology Polyurethane foam were used. Despite the delay in presentation of this linear thermal pediatric burn injury that crossed the knee joint, the patient’s response to treatment and its outcome were highly encouraging. She was cooperative and tolerated each dressing change without the need of supplemental analgesia. Her wound was healed by 24 days post-admission. In Case 2, a 25-year-old Asian man presented with a mixed thickness thermal flame burn on his left leg. On examination, the injury was a mix of deep and superficial partial thickness burn, comprising approximately 3 % of his total body surface area. SMARTPORE Technology polyurethane foam was used on his wound; his response to the treatment was very encouraging as the dressing facilitated physiotherapy and mobility. The patient rated the pain during dressing change as 2 on a scale of 10 and his pain score remained the same in every subsequent change. His wound showed evidence of epithelialization by day 7 post-burn. There were no adverse events reported.

Conclusions

Managing burn wounds with SMARTPORE Technology polyurethane foam resulted in reduced pain during dressing changes and the successful healing of partial and mixed thickness wounds. The use of SMARTPORE Technology polyurethane foam dressings showed encouraging results and requires further research as a desirable management option in burn wounds.

A Systematic Review of Comparison of Autologous, Allogeneic, and Synthetic Augmentation Grafts in Nipple Reconstruction

BACKGROUND

Many techniques have been described for nipple reconstruction, with the principal limitation being excessive loss of projection. The ideal reconstructed nipple provides sustained projection, the fewest complications, and high levels of patient satisfaction. A variety of materials are available for projection augmentation, including autologous, allogeneic, and synthetic materials. To date, there has been no systematic review to study the efficacy, projection, and complication rates of different materials used in nipple reconstruction.

METHODS

MEDLINE, Embase, and PubMed databases were searched, from inception to August of 2014, to identify literature reporting on outcomes of autologous, allogeneic, and synthetic grafts in nipple reconstruction. Retrospective and prospective studies with controlled and uncontrolled conditions were included. Studies reporting the use of autologous flap techniques without grafts and articles lacking postoperative outcomes were excluded. Study quality was assessed using the Newcastle-Ottawa Scale.

RESULTS

Thirty-one studies met the inclusion criteria. After evidence review, one study represented two of nine stars on the Newcastle-Ottawa Scale, two studies represented three stars, six studies represented four stars, seven studies represented five stars, 11 studies represented six stars, and four studies represented seven stars.

CONCLUSIONS

The results of this review revealed heterogeneity in the type of material used within each category and inconsistent methodology used in outcomes assessment in nipple reconstruction. Overall, the quality of evidence is low. Synthetic materials have higher complication rates and allogeneic grafts have nipple projection comparable to that of autologous grafts. Further investigation with high-level evidence is necessary to determine the optimal material for nipple reconstruction.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Effect of Obesity on Outcomes of Forefoot Surgery

BACKGROUND

Forefoot surgery typically is elective, so it is important to define risk factors to educate patients on potential complications. The purpose of this study was to determine if obesity is an independent risk factor that contributes to increased complication rates after forefoot surgery.

METHODS

Through a retrospective review of records, 633 patients were identified who had forefoot surgery at one institution between 2008 and 2010. All patients who currently smoked or smoked in the past were excluded to eliminate a confounding factor, as smoking is known to increase complication rates, leaving 427 patients for inclusion, 299 nonobese (BMI less than 30) and 128 obese (BMI more than 30). Medical records were reviewed for the occurrence of complications, including nonunion, delayed union, delayed wound healing, infection, and persistent pain.

RESULTS

The overall complication rate was 9%, with similar rates between obese (10%) and nonobese patients (9%). The only specific complication approaching significance (P = .13) was a higher rate of infection in obese patients (4 % compared to 1%), which could be attributed to the higher percentage of diabetic patients in the obese group. Diabetic patients, regardless of weight, had significantly higher rates of infection (P = .03), with a trend toward higher rates of overall complications and delayed wound healing (P = .08 and P < .06, respectively).

CONCLUSION

Obesity was not shown to lead to more frequent complications after forefoot surgery. Diabetes was associated with significantly higher rates of infection, regardless of weight. Though not significant, there was a trend toward higher rates of overall complications and delayed wound healing in diabetic patients as well.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Fluorinated methacrylamide chitosan hydrogels enhance collagen synthesis in wound healing through increased oxygen availability

In this study, methacrylamide chitosan modified with perfluorocarbon chains (MACF) is used as the base material to construct hydrogel dressings for treating dermal wounds. MACF hydrogels saturated with oxygen (+O2) are examined for their ability to deliver and sustain oxygen, degrade in a biological environment, and promote wound healing in an animal model. The emerging technique of metabolomics is used to understand how MACF+O2 hydrogel dressings improve wound healing. Results indicate that MACF treatment facilitates oxygen transport rate that is two orders of magnitude greater than base MAC hydrogels. MACF hydrogel dressings are next tested in an in vivo splinted rat excisional wound healing model. Histological analysis reveals that MACF+O2 dressings improve re-epithelialization (p<0.0001) and synthesis of collagen over controls (p<0.01). Analysis of endogenous metabolites in the wounds using global metabolomics demonstrates that MACF+O2 dressings promotes a regenerative metabolic process directed toward hydroxyproline and collagen synthesis, with confirmation of metabolite levels within this pathway. The results of this study confirm that increased oxygen delivery through the application of MACF+O2 hydrogels enhances wound healing and metabolomics analyses provides a powerful tool to assess wound healing physiology.

STATEMENT OF SIGNIFICANCE

This work presents the first application of a novel class of oxygen delivering biomaterials (methacrylamide chitosan modified with perfluorocarbon chains (MACF)) as a hydrogel wound dressing. This manuscript also contains strong focus on the biochemical benefits of MACF dressings on underlying mechanisms vital to successful wound healing. In this vein, this manuscript presents the application of applied metabolomics (tandem mass spectroscopy) to uncover biomaterial interactions with wound healing mechanisms. We believe the approaches described in this manuscript will be of great interest to biomedical scientists and particularly to researchers studying wound healing, metabolomics, applied biomaterials and regenerative medicine.

Traditional Therapies for Skin Wound Healing

Significance: The regeneration of healthy and functional skin remains a huge challenge due to its multilayer structure and the presence of different cell types within the extracellular matrix in an organized way. Despite recent advances in wound care products, traditional therapies based on natural origin compounds, such as plant extracts, honey, and larvae, are interesting alternatives. These therapies offer new possibilities for the treatment of skin diseases, enhancing the access to the healthcare, and allowing overcoming some limitations associated to the modern products and therapies, such as the high costs, the long manufacturing times, and the increase in the bacterial resistance. This article gives a general overview about the recent advances in traditional therapies for skin wound healing, focusing on the therapeutic activity, action mechanisms, and clinical trials of the most commonly used natural compounds. New insights in the combination of traditional products with modern treatments and future challenges in the field are also highlighted. Recent Advances: Natural compounds have been used in skin wound care for many years due to their therapeutic activities, including anti-inflammatory, antimicrobial, and cell-stimulating properties. The clinical efficacy of these compounds has been investigated through in vitro and in vivo trials using both animal models and humans. Besides the important progress regarding the development of novel extraction methods, purification procedures, quality control assessment, and treatment protocols, the exact mechanisms of action, side effects, and safety of these compounds need further research. Critical Issues: The repair of skin lesions is one of the most complex biological processes in humans, occurring throughout an orchestrated cascade of overlapping biochemical and cellular events. To stimulate the regeneration process and prevent the wound to fail the healing, traditional therapies and natural products have been used with promising results. Although these products are in general less expensive than the modern treatments, they can be sensitive to the geographic location and season, and exhibit batch-to-batch variation, which can lead to unexpected allergic reactions, side effects, and contradictory clinical results. Future Directions: The scientific evidence for the use of traditional therapies in wound healing indicates beneficial effects in the treatment of different lesions. However, specific challenges remain unsolved. To extend the efficacy and the usage of natural substances in wound care, multidisciplinary efforts are necessary to prove the safety of these products, investigate their side effects, and develop standard controlled trials. The development of good manufacturing practices and regulatory legislation also assume a pivotal role in order to improve the use of traditional therapies by the clinicians and to promote their integration into the national health system. Current trends move to the development of innovative wound care treatments, combining the use of traditional healing agents and modern products/practices, such as nanofibers containing silver nanoparticles, Aloe vera loaded into alginate hydrogels, propolis into dressing films, and hydrogel sheets containing honey.

Lactobacillus reuteri 6475 Increases Bone Density in Intact Females Only under an Inflammatory Setting

BACKGROUND & AIMS

We previously demonstrated that short-term oral administration of the probiotic Lactobacillus reuteri 6475 enhanced bone density in male but not female mice. We also established that L. reuteri 6475 enhanced bone health and prevented bone loss in estrogen-deficient female mice. In this study, we tested whether a mild inflammatory state and/or a long-term treatment with the probiotic was required to promote a positive bone effect in estrogen-sufficient female mice.

METHODS

A mild inflammatory state was induced in female mice by dorsal surgical incision (DSI). Following DSI animals were orally supplemented with L. reuteri or vehicle control for a period of 8 weeks. Gene expression was measured in the intestine and bone marrow by qPCR. Distal femoral bone density and architecture was analyzed by micro-CT.

RESULTS

We report that 8 weeks after DSI there is a significant increase in the weight of spleen, thymus and visceral (retroperitoneal) fat pads. Expression of intestinal cytokines and tight junction proteins are also altered 8 weeks post-DSI. Interestingly, L. reuteri treatment was found to display both intestinal region- and inflammation-dependent effects. Unexpectedly we identified that 1) L. reuteri treatment increased bone density in females but only in those that underwent DSI and 2) DSI benefited cortical bone parameters. In the bone marrow, dorsal surgery induced CD4+ T cell numbers, a response that was unaffected by L. reuteri treatment, whereas expression of RANKL, OPG and IL-10 were significantly affected by L. reuteri treatment.

CONCLUSION

Our data reveals a previously unappreciated effect of a mild surgical procedure causing a long-lasting effect on inflammatory gene expression in the gut and the bone. Additionally, we demonstrate that in intact female mice, the beneficial effect of L. reuteri on bone requires an elevated inflammatory status.

Topical Moltkia coerulea hydroethanolic extract accelerates the repair of excision wound in a rat model

PURPOSE

To evaluate the effect of a hydroethanolic extract of Moltkia coerulea ointment (MCO) on the healing of excision wound in a rat model.

METHODS

Circular surgical full thickness excision wound, with 314 mm² size, was induced in the anterior-dorsal side of each rat. Three different doses of MCO (1%, 3% and 6%) were administrated. On Day 3, 7, 14 and 21, the tissue was sampled and immune cells, fibroblasts and fibrocytes distribution per one mm² of wound area, collagen density and re-epithelialization were analyzed. Moreover, the total flavnoid, phenols and anti-oxidant potential of the MCO were evaluated. Ultimately, the percentage of wound contraction in different groups was compared with each other.

RESULTS

Hydroethanolic extract of MCO significantly (p < 0.05) increased wound contraction percentage. The animals in medium and high dose MCO-treated groups exhibited remarkably (p<0.05) higher fibroblast and fibrocyte distribution and significantly (p < 0.05) lower immune cells infiltration. On Day 7 after injury, MCO up-regulated neovascularization in a dose-dependent way.

CONCLUSION

Our data showed that MCO shortened the inflammation phase by provoking the fibroblast proliferation. Moreover, MCO promoted the healing process by up-regulating the angiogenesis and provoking the structural cells proliferation as well as increasing the collagen synthesis, cross-linking, and deposition.

Nesfatin-1 improves oxidative skin injury in normoglycemic or hyperglycemic rats

Hyperglycemia is one of the major causes of suppressed angiogenesis and impaired wound healing leading to chronic wounds. Nesfatin-1 a novel peptide was reported to have antioxidant and anti-apoptotic properties. This study is aimed to investigate the potential healing-promoting effects of nesfatin-1 in non-diabetic or diabetic rats with surgical wounds. In male Sprague-Dawley rats, hyperglycemia was induced by intraperitoneal (ip) injection of streptozotocin (55 mg/kg). Under anesthesia, dorsum skin tissues of normoglycemic (n=16) and hyperglycemic rats were excised (2 × 2 cm, full-thickness), while control rats (n=16) had neither hyperglycemia nor wounds. Half of the rats in each group were treated ip with saline, while the others were treated with nesfatin-1 (2 μg/kg/day) for 3 days until they were decapitated. Plasma interleukin-1-beta (IL-1β), transforming growth factor-beta (TGF-β-1), IL-6 levels, and dermal tissue malondialdehyde (MDA), glutathione (GSH) levels, myeloperoxidase (MPO) and caspase-3 activity were measured. For histological examination, paraffin sections were stained with hematoxylin-eosin or Masson's trichrome and immunohistochemistry for vascular endothelial growth factor (VEGF) was applied. ANOVA and Student's t-tests were used for statistical analysis. Compared to control rats, skin MPO activity, MDA and caspase-3 levels were increased similarly in saline-treated normo- and hyperglycemic rats. Nesfatin-1 depressed MDA, caspase-3, MPO activity and IL-1β with concomitant elevations in dermal GSH and plasma TGF-β-1 levels. Histopathological examination revealed regeneration of epidermis, regular arrangement of collagen fibers in the dermis and a decrease in VEGF immunoreactivity in the epidermal keratinocytes of nesfatin-1-treated groups. Nesfatin-1 improved surgical wound healing in both normo- and hyperglycemic rats via the suppression of neutrophil recruitment, apoptosis and VEGF activation.

Effects of Silk Sericin on Incision Wound Healing in a Dorsal Skin Flap Wound Healing Rat Model

Background

The wound healing process is complex and still poorly understood. Sericin is a silk protein synthesized by silk worms (Bombyx mori). The objective of this study was to evaluate in vivo wound healing effects of a sericin-containing gel formulation in an incision wound model in rats.

Material/Methods

Twenty-eight Wistar-Albino rats were divided into 4 groups (n=7). No intervention or treatment was applied to the Intact control group. For other groups, a dorsal skin flap (9×3 cm) was drawn and pulled up with sharp dissection. The Sham operated group received no treatment. The Placebo group received placebo gel without sericin applied to the incision area once a day from day 0 to day 9. The Sericin Group 3 received 1% sericin gel applied to the incision area once a day from day 0 to day 9. Hematoxylin and eosin stain was applied for histological analysis and Mallory-Azan staining was applied for histoimmunochemical analysis of antibodies and iNOS (inducible nitric oxide synthase), and desmin was applied to paraffin sections of skin wound specimens. Parameters of oxidative stress were measured in the wound area.

Results

Epidermal thickness and vascularization were increased, and hair root degeneration, edema, cellular infiltration, collagen discoloration, and necrosis were decreased in Sericin group in comparison to the Placebo group and the Sham operated group. Malonyldialdehyde (MDA) levels were decreased, but superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activities were increased in the sericin group.

Conclusions

We found that sericin had significant positive effects on wound healing and antioxidant activity. Sericin-based formulations can improve healing of incision wounds.

Compromised Wound Healing in Ischemic Type 2 Diabetic Rats

Ischemia is one of the main epidemic factors and characteristics of diabetic chronic wounds, and exerts a profound effect on wound healing. To explore the mechanism of and the cure for diabetic impaired wound healing, we established a type 2 diabetic rat model. We used an 8weeks high fat diet (HFD) feeding regimen followed by multiple injections of streptozotocin (STZ) at a dose of 10mg/kg to induce Wister rat to develop type 2 diabetes. Metabolic characteristics were assessed at the 5th week after the STZ injections to confirm the establishment of diabetes mellitus on the rodent model. A bipedicle flap, with length to width ratio 1.5, was performed on the back of the rat to make the flap area ischemic. Closure of excisional wounds on this bipedicle flap and related physiological and pathological changes were studied using histological, immunohistochemical, real time PCR and protein immunoblot approaches. Our results demonstrated that a combination of HFD feeding and a low dose of STZ is capable of inducing the rats to develop type 2 diabetes with noticeable insulin resistance, persistent hyperglycemia, moderate degree of insulinemia, as well as high serum cholesterol and high triglyceride levels. The excision wounds on the ischemic double pedicle flap showed deteriorative healing features comparing with non-ischemic diabetic wounds, including: delayed healing, exorbitant wound inflammatory response, excessive and prolonged ROS production and excessive production of MMPs. Our study suggested that HFD feeding combined with STZ injection could induce type 2 diabetes in rat. Our ischemic diabetic wound model is suitable for the investigation of human diabetic related wound repair; especically for diabetic chronic wounds.

Cytokines during periodontal wound healing: potential application for new therapeutic approach

Regeneration of periodontal tissues is one of the main goals of periodontal therapy. However, current treatment, including surgical approach, use of membrane to allow maturation of all periodontal tissues, or use of enamel matrix derivatives, presents limitations in their indications and outcomes leading to the development of new tissue engineering strategies. Several cytokines are considered as key molecules during periodontal destruction process. However, their role during each phase of periodontal wound healing remains unclear. Control and modulation of the inflammatory response and especially, release of cytokines or activation/inhibition in a time- and spatial-controlled manner may be a potential perspective for periodontal tissue engineering. The aim of this review was to summarize the specific role of several cytokines during periodontal wound healing and the potential therapeutic interest of inflammatory modulation for periodontal regeneration especially related to the expression sequence of cytokines.

MicroCT angiography detects vascular formation and regression in skin wound healing

Properly regulated angiogenesis and arteriogenesis are essential for effective wound healing. Tissue injury induces robust new vessel formation and subsequent vessel maturation, which involves vessel regression and remodeling. Although formation of functional vasculature is essential for healing, alterations in vascular structure over the time course of skin wound healing are not well understood. Here, using high-resolution ex vivo X-ray micro-computed tomography (microCT), we describe the vascular network during healing of skin excisional wounds with highly detailed three-dimensional (3D) reconstructed images and associated quantitative analysis. We found that relative vessel volume, surface area and branching number are significantly decreased in wounds from day 7 to days 14 and 21. Segmentation and skeletonization analysis of selected branches from high-resolution images as small as 2.5μm voxel size show that branching orders are decreased in the wound vessels during healing. In histological analysis, we found that the contrast agent fills mainly arterioles, but not small capillaries nor large veins. In summary, high-resolution microCT revealed dynamic alterations of vessel structures during wound healing. This technique may be useful as a key tool in the study of the formation and regression of wound vessels.

Acute stimulation of mesenchymal stem cells with cigarette smoke extract affects their migration, differentiation, and paracrine potential

Mesenchymal stem cells (MSCs) are known to play a key role in tissue regeneration, while smoking cigarettes is described to impair it. This work focuses on the effect cigarette smoke extract (CSE) has on the migration, differentiation, and paracrine potential of human adipose derived MSCs (AdMSCs). To mimic native conditions in vitro, AdMSCs were cultured in either monolayer or three-dimensional pellet cultures. While constant exposure to high concentrations of CSE had lethal effects on AdMSCs, lower concentrations of CSE impaired cell migration when compared to control conditions. The secretion of key interleukins was downregulated when CSE was exposed to the cells at low concentrations. Moreover, in this work AdMSCs were exposed to CSE while simultaneously being induced to differentiate into adipocytes, osteoblasts, and chondrocytes to determine the effect of CSE on the cells potential to differentiate. While adipogenic differentiation showed no significant variation, AdMSCs exposed to osteogenic and chondrogenic supplements showed both early and late genetic level variation when acutely exposed to low concentrations of CSE. Our results indicate that even a small amount of cigarette smoke can have detrimental effects on the regenerative potential of MSCs.

Wound Healing Concepts in Clinical Practice of OMFS

BACKGROUND

Wound healing is a complex and dynamic process and a thorough knowledge of the basics of physiology of wound healing is a must to implement principles of chronic wound care. Understanding wound healing at multiple levels-biochemical, physiologic, cellular and molecular provides the surgeon with a framework for basing clinical decisions aimed at optimizing the healing response.

OBJECTIVE

This review article describes the classification of wounds and aims to highlight the fundamentals of wound repair, enumerating the dressings used commonly and also, the newer concepts of wound healing.

MATERIALS AND METHODS

Search engines and medical databases were tapped to gather information on the subject. Search words employed were "Wounds", "wounds in OSMF", "Wound healing", "Repair", "Dressings in OMFS".

RESULTS

The search resulted in total of 153 articles which we reviewed to add to the literature the concepts of wound healing and to throw some light on recent advances in wound care.

CONCLUSIONS

Wound healing remains a challenging clinical problem and correct, efficient wound management is essential to positively influence the wound healing course and reduce potential complications.

Smoking, chronic wound healing, and implications for evidence-based practice

Chronic wounds are rising in prevalence and creating significant socioeconomic burdens for patients and healthcare systems worldwide. Therefore, it is now more important than ever that clinicians follow evidence-based guidelines for wound care when developing personalized treatment plans for their patients with chronic wounds. Evidence-based guidelines for treating venous leg ulcers, diabetic foot ulcers, and pressure ulcers, the 3 main categories of chronic wounds, focus primarily on biologic therapies. However, there are also evidence-based guidelines for treating behavioral risks to poor healing, such as smoking, which should be incorporated into treatment plans when appropriate. The purpose of this article was to review the mechanisms through which smoking adversely impacts the wound healing process, and propose strategies for incorporating evidence-based guidelines for treating tobacco dependence into treatment plans for patients with chronic wounds who smoke.

Epidermal Grafting for Chronic Complex Wounds in India: A Case Series

BACKGROUND : In India, the high cost of medical treatments and limited resources can deter patients from receiving available care, leading to the development of chronic wounds. We evaluated the use of epidermal grafting in patients with complex, long-term chronic wounds.

METHODS

Eighteen patients with complex wounds were treated with epidermal micrografts between September 2014 and March 2015 at a state-run, community health center in Mahe, Puducherry, India. Wound re-epithelialization was monitored for up to 14 weeks. RESULTS : Comorbidities in the patient group (nine females and nine males; mean age 54.1 ± 10.8 years, range 32-70 years) included diabetes mellitus, hypertension, obesity (body mass index (BMI) >30 kg/m(2)), and peripheral vascular disease. The wound types included diabetic and nondiabetic foot, pressure, and venous leg ulcers. The average wound age prior to treatment was 36.8 ± 48.5 months (range 2-180 months) in the majority of patients. All wounds measured less than 7 cm × 7 cm. The mean time to wound epithelialization was 3.7 ± 1.8 weeks (range 2-9 weeks). The majority of wounds healed following epidermal grafting (n=16, 88.9%). One patient developed infection following removal of the dressing under non-sterile conditions against the advice of the healthcare providers. Another patient developed wound hypergranulation after grafting. Both wounds healed completely after treatment with antibiotic therapy and tissue resection, respectively. All donor sites healed without complications. CONCLUSION : In patients with small- to medium-sized chronic wounds, epidermal grafting offered a viable wound closure option for wounds requiring only the epidermal layer. Additionally, epidermal grafting was performed in the clinic without anesthesia or a surgeon, making the procedure more accessible in resource-challenged regions.

Histological Evaluation of Wound Healing Process after Photodynamic Therapy of Rat Oral Mucosal Ulcer

STATEMENT OF THE PROBLEM

When the body defense is compromised, wounds can act as a route for entrance and colonization of microorganisms in the body. Photodynamic therapy with methylene blue is known as a promising antimicrobial modality.

PURPOSE

The present study aimed to investigate the effects of this procedure on wound healing processes.

MATERIALS AND METHOD

In this experimental study, 48 male Wistar rats were recruited. Experimental wounds were surgically made on their buccal mucosa. Based on the treatment modality, they were divided into 3 groups (n=16) of control (CG), laser (LG), photosensitizer+ laser (PLG) by methylene blue (MB). The treatment procedure in the two latter groups was done in days 1-4 and 6-9. After sacrificing on 2, 4, 7 and 14-day follow-ups, the microscopic grade of healing of the wounds was assigned on each interval according to histological grading criteria.

RESULTS

A qualitative result was obtained that showed a healing progression in PLG at day 2 of follow-up. At day 4 of follow-up, no difference was seen in healing stage among the groups. However on day 7 of follow-up, samples of the LG showed a lower degree of healing compared with the other two groups. Likewise, on day 14 of follow- up, both PLG and LG showed lower degree of healing than CG.

CONCLUSION

This study qualitatively showed that MB- mediated photodynamic therapy would have an inhibitory effect on healing process after 14 days of the wound creation.

Bioactive PLGA-curcumin microparticle-embedded chitosan scaffold: in vitro and in vivo evaluation

Wound healing is a complex process affected by several factors. In the present work, novel biocompatible PLGA-curcumin microparticle-embedded chitosan scaffold was fabricated for wound-healing application. Process variables involved in the preparation of microparticles were optimized using design of experiment. Scanning electron microscopy (SEM) confirmed the porous nature of scaffold with embedded microparticles. A maximum release of 14% of the encapsulated curcumin was observed at 12th hour. Modified tube dilution method showed that scaffold significantly (p < 0.05) reduced multiplication of Staphylococcus aureus. More than 50% of the excised wound in rats healed in 4 days with an epithilization period of 18 days.

Tumor volume is a better predictor of post-operative wound complications compared to tumor size in soft tissue sarcomas of the proximal lower extremity

Background

Wide local excision with or without radiation therapy (RT) and chemotherapy is widely accepted as appropriate management for soft tissue sarcomas (STS) of the extremity. Although survival and local control rates are comparable to amputation, post-operative wound complications (WC) following limb salvage can result in significant morbidity for the patient. Certain risk factors such as location, pre-operative RT, and age have been shown to increase the risk of WCs. Somewhat surprisingly, size has not consistently been shown to impact WC rates. The goal of this study is to assess whether tumor volume, as opposed to the traditional measurement of the largest dimension in one plane, correlates with the development of post-operative WCs.

Methods

Between 2000 and 2013, 81 patients with STS of the proximal lower extremity, buttock and pelvis were retrospectively identified from our prospective database. We reviewed the impact of patient, tumor, and treatment variables on postoperative WC. Predictors for WC were evaluated using the Fisher exact test for univariate analysis and logistic regression for multivariate analysis. Tumor volume was determined using the medical image merge (MIM) ^® software program (version 6.5.4, MIM Software, Cleveland, OH). Tumor size (diameter) was determined the historical way of measuring the widest dimension on the sagittal, coronal, and axial planes from the MRI scan at midplane.

Results

The overall WC rate within 6 months of tumor resection was 32 %. WC were more likely to occur with larger tumor volumes (p = 0.015), although not with tumor diameters ≥10 cm (p = 0.55). Neither volume of subcutaneous fat (p = 0.34) or depth of the subcutaneous fat layer (p = 0.82) significantly impacted WC rates. Tumor proximity to skin surface also did not significantly impact WC risk (p = 0.73).

Conclusions

Increase in tumor volume led to a higher risk of post-operative WCs. Assessing tumor volume may allow clinicians to better counsel patients on their risk of post-operative WCs. Tumor volume, as opposed to size alone, should be considered in future sarcoma outcome studies.

Skin and muscle permeating antibacterial nanoparticles for treating Staphylococcus aureus infected wounds

Majority of the chronic wounds are infected with bacteria like Staphylococcus aureus (S. aureus). The deep tissue infections are difficult to treat using topical antibiotics, due to their poor tissue penetration. In order to treat S. aureus deep tissue infections we have developed an antibiotic delivery system using chitosan nanoparticles (CNPs). To enhance their tissue penetration these CNPs were further coated using lecithin (CLNPs). Antibiotic tigecycline was loaded into chitosan nanoparticles (tCNPs) and then coated with lecithin to generate lecithin coated tigecycline loaded chitosan nanoparticles (tCLNPs). The prepared nanoparticles were characterized using DLS, SEM, TEM and FT-IR. The prepared CNPs, tCNPs, CLNPs and tCLNPs have the size range of 85 ± 10, 90 ± 18, 188 ± 5 and 235 ± 20 nm, respectively. The tCLNPs shows more sustained release pattern of tigecycline. The antibacterial activity of the developed nanoparticles was confirmed against laboratory and clinical strains of S. aureus using in vitro and ex vivo experiments. The ex vivo skin and muscle permeation study ensures the enhanced delivery of tigecycline to the deeper tissue. The prepared nanoparticles were hemo-compatible and cyto-compatible. Our study suggests that the prepared tCLNPs can be effectively used for the treatment of S. aureus infected wounds.

Development of a Nutrition Screening Tool for an Outpatient Wound Center

OBJECTIVE

To construct a quickly and easily administered nutrition screening tool using variables believed to be predictive of malnutrition risk in the wound patient population.

DESIGN

A prospective pilot study assessed patients on a list of suspected variables, as well as the Scored Patient-Generated Subjective Global Assessment (PG-SGA), chosen as the criterion standard. Variables were analyzed to select the most appropriate items for inclusion on a new nutrition screening tool using preliminary bivariate correlations and χ tests of association. Items significantly associated with malnutrition were dichotomized, and binary logistic regression analyses were performed to arrive at a final model. A sum score was computed, and receiver operating characteristic analysis was used to determine designation of risk.

SETTING

An outpatient wound center in Northeast Ohio.

PARTICIPANTS

The pilot study included a convenience sample of 105 outpatients with at least 1 active wound.

MAIN OUTCOME MEASURES

Malnutrition as assessed by the Scored PG-SGA.

MAIN RESULTS

The final nutrition screening tool, the MEAL Scale, is composed of 4 dichotomous elements: multiple wounds (number of wounds), eats less than 3 meals per day, appetite decrease (eats less than usual), and level of activity. These variables predicted 83.7% of the malnutrition cases assessed by the Scored PG-SGA. The receiver operating characteristic analysis showed an acceptable area under the curve (0.8581), and a cutoff score of 2 or greater was selected to indicate risk (median sensitivity = 91.4%, median specificity = 60.9%).

CONCLUSIONS

Although further studies of validity and reliability are necessary to establish the tool before widespread use, the MEAL Scale is a needed step toward nutrition screening in a wound patient population.

Modulation of ROS levels in fibroblasts by altering mitochondria regulates the process of wound healing

Mitochondria are the major source of reactive oxygen species (ROS) in fibroblasts which are thought to be crucial regulators of wound healing with a potential to affect the expression of nuclear genes involved in this process. ROS generated by mitochondria are involved in all stages of tissue repair process but the regulation of ROS-generating system in fibroblasts still remains poorly understood. The purpose of this study was to better understand molecular mechanisms of how the regulation of ROS levels generated by mitochondria may influence the process of wound repair. Cybrid model system of mtDNA variations was used to study the functional consequences of altered ROS levels on wound healing responses in a uniform nuclear background of cultured ρ(0) fibroblasts. Mitochondrial ROS in cybrids were modulated by antioxidants that quench ROS to examine their ability to close the wound. Real-time PCR arrays were used to investigate whether ROS generated by specific mtDNA variants have the ability to alter expression of some key nuclear-encoded genes central to the wound healing response and oxidative stress. Our data suggest levels of mitochondrial ROS affect expression of some nuclear encoded genes central to wound healing response and oxidative stress and modulation of mitochondrial ROS by antioxidants positively affects in vitro process of wound closure. Thus, regulation of mitochondrial ROS-generating system in fibroblasts can be used as effective natural redox-based strategy to help treat non-healing wounds.

First clinical experience of the safety and feasibility of total subcutaneous implantable defibrillator in an Asian population

AIMS

The safety and feasibility of a subcutaneous implantable cardioverter-defibrillator (S-ICD) has been demonstrated in the treatment of life-threatening ventricular tachyarrhythmias (VT). Nonetheless, its safety and feasibility in an Asian population with smaller body-build is unclear.

METHODS AND RESULTS

Twenty-one Asian patients who underwent S-ICD from 1 April 2014 to 2 February 2015 in five institutions in Hong Kong and Singapore were retrospectively reviewed. Twenty-one patients with a mean age of 50.0 ± 14.1 years (range 29-77 years, 82.6% male) were included. Among them, 17 (81.0%) were Chinese, 3 (14.3%) were Malay, and 1 (4.8%) was Indian. Their mean body mass index was 23.0 ± 4.0 kg/m(2). An S-ICD was implanted for primary and secondary prevention in 13 (61.9%) and 8 (38.1%) patients, respectively. The indications included Brugada syndrome (n = 6, 28.6%), ischaemic cardiomyopathy (CMP, n = 6, 28.6%), dilated CMP (n = 4, 19.0%), hypertrophic CMP (n = 2, 9.5%), and idiopathic ventricular fibrillation (n = 2, 9.5%). Three patients (14.3%) had prior infected transvenous ICD. There were no acute complications but eight wound complications (persistent wound bleeding requiring intervention = 2; delayed wound healing: upper sternal wound = 3; generator site = 1; local wound infection = 2) were observed in six (28.2%) patients. After a mean follow-up of 107.2 ± 81.3 days (range of 14-254 days), one patient underwent three successful appropriate shocks for treatment of VTs. No inappropriate therapy was documented.

CONCLUSION

Our initial experience shows that S-ICD is a feasible treatment for VT among an Asian population with smaller body-build. There was nonetheless a relatively high rate of wound complications.

Slough and biofilm: removal of barriers to wound healing by desloughing

The presence of non-viable tissue in a chronic wound presents a barrier against effective wound healing, hence removal facilitates healing and reduces areas where microorganisms can attach and form biofilms, effectively reducing the risk of infection. Wound debridement is a necessary process in those wounds that have evidence of cellular debris and non-viable tissue. As slough is a form of non-viable tissue we hypothesise that it will support the attachment and development of biofilms. Biofilms are entities that have serious implications in raising the risk of infection and delaying wound healing. In those wounds that contain only slough, high-risk debridement methods are not considered necessary for its removal. The use of mechanical techniques for removing the slough is regarded as posing a much lower risk to the patient and the wound bed. The process of removing slough from a wound is referred to as 'desloughing'. We propose that mechanical desloughing is a low-risk method of debridement to aid the specific removal of slough. Slough in a wound is a recurrent issue for a large majority of patients. Consequently, desloughing should not be deemed a one-off process but an on-going procedure referred to as 'maintenance desloughing'. Maintenance desloughing will help to achieve and maintain a healthy wound bed and aid the removal of wound biofilms, facilitating wound healing.

Comparative Study of Morphometric and Fourier Transform Infrared Spectroscopy Analyses of the Collagen Fibers in the Repair Process of Cutaneous Lesions

Objective: Compare the efficacy of light-emitting diode (LED) and therapeutic ultrasound (TUS), combined with a semipermeable dressing (D), at forming collagen in skin lesions by morphometry and Fourier transform infrared spectroscopy (FT-IR). Materials and Methods: Surgical skin wounds (2.5 cm) were created on 84 male Wistar rats divided into four groups (n=21): Group I (Control), Group II (LED), Group III (LED+D), and Group IV (US+D). On days 7, 14, and 21, the tissue samples were removed and divided into two pieces, one was used for histological examination (collagen) and the other for FT-IR. Results: The histomorphometric analysis showed no significant differences among groups for collagen deposition at 7 days. However, at 14 days, more deposition of collagen was noted in the groups LED (p<0.05) and LED+D (p<0.001) than in the control. At 21 days, the groups LED, LED+D, and US+D presented significantly greater deposition of collagen when compared with the control. The FT-IR spectra, at 14 days, LED+D had greater amounts of type I collagen, a better organization of fibers, and greater difference of mean separation between the groups, not observed at 7 and 21 days. Innovation: The histomorphometric and FT-IR analyses suggest that the association of semipermeable dressing to LED therapy and to TUS modulates biological events, increasing fibroblast/collagen response and accelerating dermal maturation. Conclusion: The histomorphometric and FT-IR analyses showed that LED therapy is more efficacious than TUS, when combined with a semipermeable dressing, and induced the collagen production in skin lesions.

Imparting commercial antimicrobial dressings with low-adherence to burn wounds

The objective of our study was to decrease the wound adherence of commercial silver based wound dressings by depositing a non-adherent layer. Our hypothesis was that this non-adherent layer will lower the dressing's adherence to burn wounds without compromising the antimicrobial activity or increasing the cytotoxicity. A polyacrylamide (PAM) hydrogel layer was grafted on two commercial silver antimicrobial dressings (silver nanocrystal dressing (NC) and silver plated dressing (SP)) using a proprietary technique. The grafted PAM served as the non-adherent layer. Dressing adherence was measured with a previously published in vitro gelatin model using an Instron mechanical force testing instrument. The dressings were challenged with two clinically retrieved bacterial strains (Methicillin-resistant Staphylococcus aureus (MRSA) and multidrug resistant (MDR) Pseudomonas aeruginosa) with both a disk diffusion test, and a suspension antibacterial test. The cytotoxicity of samples to human neonatal fibroblast cells was evaluated with 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide (MTT) assay. Both untreated dressings showed high peeling energy: 2070±453J/m(2) (NC) and 669±68J/m(2) (SP), that decreased to 158±119J/m(2) (NC) and 155±138J/m(2) (SP) with the PAM deposition. Addition of the PAM caused no significant difference in zone of inhibition (ZOI) (disk diffusion test) or antibacterial kinetics (suspension test) against both bacteria (p>0.05, n=6) in either dressing. Survival of fibroblasts was improved by the PAM grafting from 48±5% to 60±3% viable cells in the case of NC and from 55±8% to 61±4% viable cells in SP (p<0.05, n=12). It was concluded that PAM as a non-adherent layer significantly decreases the adherence of these two commercial antimicrobial dressings in an in vitro gelatin model while preserving their antimicrobial efficacy, and reducing their cytotoxicity.

Reviewing the benefits and harm of NPWT in the management of closed surgical incisions

The use of negative pressure wound therapy (NPWT) for the treatment of open traumatic, non-traumatic, chronic wounds and coverage over skin grafts has increased in popularity over the past decade. Although the exact mechanism of the action of NPWT on wound healing is still an active area of research, evidence propose it is achieved by removing oedema, increasing blood circulation, reducing bacterial bio-burden, providing a moist wound-healing environment, and increasing granulation tissue formation. In recent years, there has been an emerging body of literature describing a novel application of NPWT on closed surgical wounds, especially on closed orthopaedic incisional (COI) wounds. It has been suggested that applying NPWT to a COI may decrease the incidence of surgical wound-healing complications, such as hematoma, seroma, infection, or dehiscence, and hasten the healing of the incision. This review will evaluate the potential effect on the reduction of postoperative closed wound complications and examine the benefits and harm of NPWT in the management of COI.

The Characterization and Prediction of ISGPF Grade C Fistulas Following Pancreatoduodenectomy

INTRODUCTION

International Study Group of Pancreatic Fistula (ISGPF) grade C postoperative pancreatic fistulas (POPF) are the greatest contributor to major morbidity and mortality following pancreatoduodenectomy (PD); however, their infrequent occurrence has hindered deeper analysis. This study sought to develop a predictive algorithm, which could facilitate effective management of this challenging complication.

METHODS

Data were accrued from 4301 PDs worldwide. Demographics, postoperative management, and microbiological characteristics of grade C POPFs were evaluated. American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) preoperative and intraoperative variables were compared between grade C POPFs and a 639-case sample of non-grade C POPFs. Risk factors for grade C POPF formation were identified using regression analysis.

RESULTS

Grade C POPFs developed in 79 patients (1.8 %). Deaths (90 days) occurred in 2.0 % (N = 88) of the overall series, with 35 % (N = 25) occurring in the presence of a grade C POPF. Reoperations occurred 72.2 % of the time. The rates of single- and multi-system organ failure were 28.2 and 39.7 %, respectively. Mortality rates escalated with pulmonary, renal, and neurologic organ failure, but they were unaffected by reoperation(s). The median number of complications incurred was four (IQR: 2-5), and the median duration of hospital stay was 32 (IQR: 21-54) days. Warning signs for impending grade C POPFs most often presented on postoperative day (POD) 6. Adjuvant chemotherapy might have benefited 55.7 % of grade C POPF patients, yet it was delayed in 25.6 % and never delivered in 67.4 % of these patients. Predictive models for grade C POPF occurrence based on preoperative factors alone and preoperative and intraoperative factors yielded areas under the receiver operating characteristic curve of 0.73 and 0.84 (both P < 0.000001), respectively.

CONCLUSION

This global study represents the largest analysis of grade C POPFs following PD. It describes the severe burden that grade C POPFs incur on patients, with high rates of reoperation and infection, while also potentially worsening overall survival by causing death and delay/omission of adjuvant therapy. Additionally, aggressive clinical management for these POPFs did not improve or worsen 90-day mortality. Predictive tools developed through these data may provide value in managing this difficult complication.

Sundew-Inspired Adhesive Hydrogels Combined with Adipose-Derived Stem Cells for Wound Healing

The potential to harness the unique physical, chemical, and biological properties of the sundew (Drosera) plant's adhesive hydrogels has long intrigued researchers searching for novel wound-healing applications. However, the ability to collect sufficient quantities of the sundew plant's adhesive hydrogels is problematic and has eclipsed their therapeutic promise. Inspired by these natural hydrogels, we asked if sundew-inspired adhesive hydrogels could overcome the drawbacks associated with natural sundew hydrogels and be used in combination with stem-cell-based therapy to enhance wound-healing therapeutics. Using a bioinspired approach, we synthesized adhesive hydrogels comprised of sodium alginate, gum arabic, and calcium ions to mimic the properties of the natural sundew-derived adhesive hydrogels. We then characterized and showed that these sundew-inspired hydrogels promote wound healing through their superior adhesive strength, nanostructure, and resistance to shearing when compared to other hydrogels in vitro. In vivo, sundew-inspired hydrogels promoted a "suturing" effect to wound sites, which was demonstrated by enhanced wound closure following topical application of the hydrogels. In combination with mouse adipose-derived stem cells (ADSCs) and compared to other therapeutic biomaterials, the sundew-inspired hydrogels demonstrated superior wound-healing capabilities. Collectively, our studies show that sundew-inspired hydrogels contain ideal properties that promote wound healing and suggest that sundew-inspired-ADSCs combination therapy is an efficacious approach for treating wounds without eliciting noticeable toxicity or inflammation.

Exploring the role of curcumin containing ethanolic extract obtained from Curcuma longa (rhizomes) against retardation of wound healing process by aspirin

Aim:

The aim of the study was to assess the curcumin containing ethanolic extract (EtOH) obtained from Curcuma longa (Cl) against retardation of wound healing by aspirin.

Materials and Methods:

Wound healing process was retarded by administering the dose of 150 mg/kg body weight of aspirin orally for 9 days to observe the effect of EtOH obtained from Cl using excision and incision wound model in rats. The various parameters such as % wound contraction, epithelialization period, hydroxyproline, tensile strength were observed at variant time intervals and histopathological study was also performed.

Results:

Curcumin containing 5% and 10% ethanolic extract ointment have shown significant (P < 0.01) wound healing activity against an aspirin (administered 150 mg/kg body weight orally for 9 days) retarded wound healing process. Topical application of ointment showed significant (P < 0.01) difference as compared to the control group. Histopathological studies also showed healing of the epidermis, increased collagen, fibroblasts and blood vessels.

Conclusion:

Ethanolic extract of Cl ointment (EtOHCl) containing 10% curcumin displayed remarkable healing process against wound retardation by aspirin.

Aberrant Wound Healing in an Epidermal Interleukin-4 Transgenic Mouse Model of Atopic Dermatitis

Wound healing in a pre-existing Th2-dominated skin milieu was assessed by using an epidermal specific interleukin-4 (IL-4) transgenic (Tg) mouse model, which develops a pruritic inflammatory skin condition resembling human atopic dermatitis. Our results demonstrated that IL-4 Tg mice had delayed wound closure and re-epithelialization even though these mice exhibited higher degrees of epithelial cell proliferation. Wounds in IL-4 Tg mice also showed a marked enhancement in expression of inflammatory cytokines/chemokines, elevated infiltration of inflammatory cells including neutrophils, macrophages, CD3+ lymphocytes, and epidermal dendritic T lymphocytes. In addition, these mice exhibited a significantly higher level of angiogenesis as compared to wild type mice. Furthermore, wounds in IL-4 Tg mice presented with larger amounts of granulation tissue, but had less expression and deposition of collagen. Taken together, an inflamed skin condition induced by IL-4 has a pronounced negative influence on the healing process. Understanding more about the pathogenesis of wound healing in a Th2- dominated environment may help investigators explore new potential therapeutic strategies.

Generating Primary Fibroblast Cultures from Mouse Ear and Tail Tissues

Primary cells are derived directly from tissue and are thought to be more representative of the physiological state of cells in vivo than established cell lines. However, primary cell cultures usually have a finite life span and need to be frequently re-established. Fibroblasts are an easily accessible source of primary cells. Here, we discuss a simple and quick experimental procedure to establish primary fibroblast cultures from ears and tails of mice. The protocol can be used to establish primary fibroblast cultures from ears stored at RT for up to 10 days. When the protocol is carefully followed, contaminations are unlikely to occur despite the use of non-sterile tissue stored for extended time in some cases. Fibroblasts proliferate rapidly in culture and can be expanded to substantial numbers before undergoing replicative senescence.

Assessment of Wound Complications After Bulbar Urethroplasty: The Impact of a Lambda Perineal Incision

OBJECTIVE

To analyze risk factors for wound-specific complications after bulbar urethroplasty, including the association between incision type and complications.

METHODS

This is a retrospective review of 829 urethroplasties excluding penile strictures, incomplete data sets, and radiation-induced urethral stenosis. Ninety-day wound complications were reported using the modified Clavien-Dindo classification of postoperative complications. Risk factors for wound complications were evaluated using univariable and multivariable analysis: patient age, positive preoperative urine culture, Charlson comorbidity index ≥ 2, diabetes, body mass index ≥ 35, smoking, and incision type (lambda perineal incision [LPI] vs. midline perineal incision [MPI]).

RESULTS

Five hundred forty patients met inclusion criteria; 373 patients with an LPI and 167 patients with an MPI. Ninety-day wound complications (any Clavien grade) occurred in 21% of patients. Multivariable analyses indicated that incision type alone was significantly associated with wound complications (multivariable: MPI OR 0.53 (0.34-0.83), P = .01). The majority of complications were Clavien ≤ 2, which occurred in 23.3% (87 patients) of LPIs compared to 11.9% (20 patients) of MPIs (P = .002). The primary difference between the incisions was superficial wound edge separation (LPI 10.7% [40 patients]; MPI 0%, P  <  .0001). Early (6-month) urethroplasty success favored the midline incision (LPI 6.2% vs MPI 0%, P  =  .0003), implying no obvious technical advantage for the lambda incision. Study limitations include a retrospective design and the use of some patient-reported complication outcomes.

CONCLUSION

An LPI is independently associated with increased 90-day wound complications after urethroplasty, with no identifiable advantage in urethroplasty outcome.

Dermal Patch with Integrated Flexible Heater for on Demand Drug Delivery

Topical administration of drugs and growth factors in a controlled fashion can improve the healing process during skin disorders and chronic wounds. To achieve this goal, a dermal patch is engineered that utilizes thermoresponsive drug microcarriers encapsulated within a hydrogel layer attached to a flexible heater with integrated electronic heater control circuitry. The engineered patch conformally covers the wound area and enables controlled drug delivery by electronically adjusting the temperature of the hydrogel layer. The drugs are encapsulated inside microparticles in order to control their release rates. These monodisperse thermoresponsive microparticles containing active molecules are fabricated using a microfluidic device. The system is used to release two different active molecules with molecular weights similar to drugs and growth factors and their release profiles are characterized. This platform is a key step towards engineering smart and closed loop systems for topical applications.

Self-assembling ultrashort NSAID-peptide nanosponges: multifunctional antimicrobial and anti-inflammatory materials

This paper outlines the design, synthesis and characterisation of innovative NSAID-peptide gelators which demonstrate antimicrobial and anti-inflammatory properties and have potential use as multifunctional materials for biomedical applications.

Nanomaterials as a game changer in the management and treatment of diabetic foot ulcers

Nanoengineered biomaterials have tremendously improved the range of tools utilized for the control of as well as acceleration of healing of diabetic foot ulcers (DFU) over the last few decades.

Effects of flavonoids from Martynia annua and Tephrosia purpurea on cutaneous wound healing

OBJECTIVE

Martynia annua L. (M. annua), (Martyniaccae) has been traditionally used in the treatment of epilepsy, sore throat and inflammatory disorders. The leaf paste is used topically on Tuberculosis of the lymphatic glands and wounds of domestic animals. Tephrosia purpurea (T. purpurea), (Fabaceae) has been used traditionally as a remedy for asthma, gonorrhea, rheumatism and ulcers. This study aimed to evaluate the potential wound healing effects of different fractions ofethanol extract of M. annua leaves and aerial parts of T. purpurea.

MATERIALS AND METHODS

Methanol fraction of M. annua (MAF-C) and ethyl acetate fraction of T. purpurea (TPF-A) were evaluated for healing potential in dead-space and burn wound models. An ointment (5% w/w) of MAF-C and TPF-A, pongamol (0.2 and 0.5% w/w) and luteolin (0.2 and 0.5% w/w) was applied topically twice a day. The effects were compared with Povidone Iodine ointment with respect to protein, collagen content, enzymatic assay and histopathological finding of granuloma tissues.

RESULTS

Ethanol extracts of M. annua and T. purpureawere exhibited total flavonoid contents of 126.2 ± 4.69 and 171.6 ± 6.38 mg (quercetin equivalent), respectively. HPLC fingerprinting confirmed the presence of luteolin in M. annua and quercetin in T. purpurea. TPF-A and MAF-C ointments (5% w/w) significantly increases the hydroxyproline and protein contents. Luteolin and pongamol ointments were also found to be effective in both wound models.

CONCLUSION

Our findings suggested that 5% w/w ointment of TPF-A and MAF-C fractions were more effective than isolated flavonoids in wound healing which may be due to synergistic interactions between the flavonoids and other constituents.

Hyperbaric oxygen therapy improves colorectal anastomotic healing

PURPOSE

Hyperbaric oxygen treatment (HBOT) has been found to improve the healing of poorly oxygenated tissues. This study aimed to investigate the influence of HBOT on the healing in ischemic colorectal anastomosis.

METHODS

Forty Wistar rats were randomly divided into a treatment group that received HBOT for 10 consecutive days (7 days before and 3 days after surgery), or in a control group, which did not receive the therapy. Colectomy with an ischemic anastomosis was performed in all rats. In each group, the rats were followed for 3 or 7 days after surgery to determine the influence of HBOT on anastomotic healing.

RESULTS

Five rats from each group died during follow-up. No anastomotic dehiscence was seen in the HBOT group, compared to 37.5 % and 28.6 % dehiscence in the control group on postoperative day (POD) 3 and 7, respectively. The HBOT group had a significantly higher bursting pressure (130.9 ± 17.0 mmHg) than the control group (88.4 ± 46.7 mmHg; p = 0.03) on POD 3. On POD 3 and POD 7, the adhesion severity was significantly higher in the control groups than in the HBOT groups (p < 0.005). Kidney function (creatinine level) of the HBOT group was significantly better than of the control group on POD 7 (p = 0.001). Interestingly, a significantly higher number of CD206+ cells (marker for type 2 macrophages) was observed in the HBOT group at the anastomotic area on POD 3.

CONCLUSION

Hyperbaric oxygen enhanced the healing of ischemic anastomoses in rats and improved the postoperative kidney function.