The efficacy of adipose-derived stem cells in burn injuries: a systematic review.

BACKGROUND: Burn injuries can be associated with prolonged healing, infection, a substantial inflammatory response, extensive scarring, and eventually death. In recent decades, both the mortality rates and long-term survival of severe burn victims have improved significantly, and burn care research has increasingly focused on a better quality of life post-trauma. However, delayed healing, infection, pain and extensive scar formation remain a major challenge in the treatment of burns. ADSCs, a distinct type of mesenchymal stem cells, have been shown to improve the healing process. The aim of this review is to evaluate the efficacy of ADSCs in the treatment of burn injuries. METHODS: A systematic review of the literature was conducted using the electronic databases PubMed, Web of Science and Embase. The basic research question was formulated with the PICO framework, whereby the usage of ADSCs in the treatment of burns in vivo was determined as the fundamental inclusion criterion. Additionally, pertinent journals focusing on burns and their treatment were screened manually for eligible studies. The review was registered in PROSPERO and reported according to the PRISMA statement. RESULTS: Of the 599 publications screened, 21 were considered relevant to the key question and were included in the present review. The included studies were almost all conducted on rodents, with one exception, where pigs were investigated. 13 of the studies examined the treatment of full-thickness and eight of deep partial-thickness burn injuries. 57,1 percent of the relevant studies have demonstrated that ADSCs exhibit immunomodulatory effects during the inflammatory response. 16 studies have shown improved neovascularisation with the use of ADSCs. 14 studies report positive influences of ADSCs on granulation tissue formation, while 11 studies highlight their efficacy in promoting re-epithelialisation. 11 trials demonstrated an improvement in outcomes during the remodelling phase. CONCLUSION: In conclusion, it appears that adipose-derived stem cells demonstrate remarkable efficacy in the field of regenerative medicine. However, the usage of ADSCs in the treatment of burns is still at an early experimental stage, and further investigations are required in order to examine the potential usage of ADSCs in future clinical burn care.

Radiological Influencing Factors in the Diagnosis of Painful Habitual Instability of the Thumb Basal Joint as a Precursor of Carpometacarpal Arthritis of the Thumb-A Retrospective Study.

BACKGROUND: Painful habitual instability of the thumb basal joint (PHIT) is a rarely diagnosed condition that can severely impair hand function. Furthermore, it can increase the risk of developing carpometacarpal arthritis of the thumb (CMAOT). Clinical examination and radiographic imaging provide the foundation for a correct diagnosis, but early detection is still challenging. We investigated two objective, radiographically obtainable parameters as potential risk factors for PHIT. METHODS: Clinical data and radiographic images of 33 patients suffering from PHIT were collected and compared to those of 35 people serving as the control group. The two main objectives, the slope angle and the bony offset of the thumb joint, were gathered from the X-rays and statistically analyzed. RESULTS: The analysis showed no differences between the study and the control group concerning the slope angle. Gender and the bony offset, on the other hand, had a significant influence. Female sex and higher offset values were associated with an increased risk of PHIT. CONCLUSIONS: The results of this study prove a connection between a high bony offset and PHIT. We believe this information can be valuable in early detection and will allow more efficient treatment of this condition in the future.

Workflow assessment of an augmented reality application for planning of perforator flaps in plastic reconstructive surgery: Game or game changer?

Objective: In contrast to the rising amount of financial investments for research and development in medical technology worldwide is the lack of usability and clinical readiness of the produced systems. We evaluated an augmented reality (AR) setup under development for preoperative perforator vessel mapping for elective autologous breast reconstruction. Methods: In this grant-supported research pilot, we used magnetic resonance angiography data (MR-A) of the trunk to superimpose the scans on the corresponding patients with hands-free AR goggles to identify regions-of-interest for surgical planning. Perforator location was assessed using MR-A imaging (MR-A projection) and Doppler ultrasound data (3D distance) and confirmed intraoperatively in all cases. We evaluated usability (System Usability Scale, SUS), data transfer load and documented personnel hours for software development, correlation of image data, as well as processing duration to clinical readiness (time from MR-A to AR projections per scan). Results: All perforator locations were confirmed intraoperatively, and we found a strong correlation between MR-A projection and 3D distance measurements (Spearman r = 0.894). The overall usability (SUS) was 67 ± 10 (=moderate to good). The presented setup for AR projections took 173 min to clinical readiness (=availability on AR device per patient). Conclusion: In this pilot, we calculated development investments based on project-approved grant-funded personnel hours with a moderate to good usability outcome resulting from some limitations: assessment was based on one-time testing with no previous training, a time lag of AR visualizations on the body and difficulties in spatial AR orientation. The use of AR systems can provide new opportunities for future surgical planning, but has more potential for educational (e.g., patient information) or training purposes of medical under- and postgraduates (spatial recognition of imaging data associated with anatomical structures and operative planning). We expect future usability improvements with refined user interfaces, faster AR hardware and artificial intelligence-enhanced visualization techniques.

Minimally Invasive Treatment of Trapeziometacarpal Osteoarthritis: Results of a Blinded Randomized Controlled Trial.

BACKGROUND: Surgical therapy for widespread first carpometacarpal (CMC1) arthritis permanently alters the physiologic anatomy of the hand. The injection of autologous substances into the thumb saddle joint could achieve temporary pain relief and delay surgical indications. This trial aimed to compare the pain-reducing effects of autologous fat and/or platelet-rich plasma (PRP) with saline 0.9% in the infiltration therapy of carpometacarpal arthritis of the thumb (CMC1 arthritis). METHODS: A blinded, randomized controlled trial was conducted. Ninety-five patients with CMC1 arthritis were included in the study. The mean follow-up period was 2 years. Participants were injected with 1.5 mL of autologous fat, PRP, autologous fat and PRP, or 0.9% saline solution into the CMC1 joint, depending on the group allocation. The primary outcome of this study was the evaluation of pain reduction in each treatment group. RESULTS: The combination of fat and PRP was the only treatment that resulted in a significantly greater reduction in pain compared with 0.9% saline ( P = 0.003). Similarly, fat and PRP in combination was the only therapy group to achieve clinically relevant Quick Disabilities of Arm, Shoulder, and Hand score reduction, and the only group that showed a significantly better Medical Outcomes Study 36-Item Short-Form Health Survey score than 0.9% saline ( P = 0.016). No major complications were noted. CONCLUSIONS: In addition to pain reduction, the combination of autologous fat and PRP yields a relevant improvement in hand function and a corresponding improvement in quality of life. This treatment seems to be a viable and safe alternative to short-acting glucocorticoids. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.

Does Electrical Stimulation through Nerve Conduits Improve Peripheral Nerve Regeneration?-A Systematic Review.

BACKGROUND: Peripheral nerve injuries affect over 2% of trauma patients and can lead to severe functional impairment and permanent disability. Autologous nerve transplantation is still the gold standard in the reconstruction of nerve defects. For small defects, conduits can be considered for bridging. Lately, the combined use of conduits and electrical stimulation has gained attention in the treatment of peripheral nerve injury. This review aimed to present the currently available data on this topic. METHODS: PubMed, Embase, Medline and the Cochrane Library were searched for studies on electrical stimulation through nerve conduits for nerve defects in in vivo studies. RESULTS: Fifteen studies fit the inclusion criteria. All of them reported on the application of nerve conduits combined with stimulation for sciatic nerve gaps in rats. Functional, electrophysiological and histological evaluations showed improved nerve regeneration after electrical stimulation. High variation was observed in the treatment protocols. CONCLUSION: Electrically stimulated conduits could improve peripheral nerve regeneration in rat models. The combined application of nerve guidance conduits and electrical stimulation shows promising results and should be further evaluated under standardized conditions.

Introducing the "SIMline"-A Simulation Course in the Management of Severe Burns as a Tool in Undergraduate Medical Education.

Background: Management of burn injuries presents a complex and challenging situation for medical staff, especially for inexperienced young doctors. However, training on how to treat burn victims in the clinical setting is rarely taught in undergraduate medical classes. We have created the "SIMline", a simulation training program explicitly designed for coaching medical students in burn management. Methods: A total of 43 students participated in the "SIMline" course, which took place at the training facility at the Medical University of Graz, between 2018 and 2019. The course provided theoretical classes, practical exercises, and a full-scale care process simulation training. The learning progress of the students was monitored via a formative integrated test. Results: Students showed great progress throughout the course of the "SIMline" program, as their test scores improved by an average of 88%. The passing rate was 0% at the first exam (prior to course) as compared to 87% at the final exam, taken after the training. Conclusions: Comprehensive practical training programs in burn care are underrepresented in medical education. The "SIMline" course presents a novel and effective approach in training medical students in burn management. However, follow-up evaluation is necessary to confirm long-term educational benefits.

Autologous Fat and Platelet-Rich Plasma Injections in Trapeziometacarpal Osteoarthritis: A Systematic Review and Meta-Analysis.

BACKGROUND: For the treatment of carpometacarpal arthritis of the thumb, various therapies are used. Infiltration therapy with autologous substances such as platelet-rich plasma and autologous fat have recently gained increasing attention because of beneficial pain-reducing effects in arthritis and the associated regenerative potential. However, the extent of clinical evidence in this area and how well autologous substances work in terms of pain reduction and improvements in hand function remain unclear. METHODS: A systematic review and meta-analysis were conducted to evaluate the current evidence and to provide more insight into pain reduction and improvement in hand function after infiltration of autologous substances. The authors identified 11 clinical trials, of which we included eight in the meta-analysis. RESULTS: Autologous substances achieved a good and long-lasting pain reduction, which may also be accompanied by corresponding improvement in hand function. Autologous substances appear to be more effective than corticoid infiltrations. The infiltration of autologous fat seems to be particularly promising in more advanced stages of carpometacarpal arthritis of the thumb. Our meta-analysis showed a mean pain reduction of 2.4 to 3 in visual analogue scale score and a reduction of 18 to 19 points in the Disabilities of the Arm, Shoulder, and Hand questionnaire after infiltration with autologous substances. CONCLUSION: Both platelet-rich plasma and autologous fat infiltration offer an efficient and long-lasting, minimally invasive therapy option in the treatment of carpometacarpal arthritis of the thumb.

Earlobe Correction of the Pierced Ear: A Systematic Review of the Literature and Principles for Surgical Reconstruction.

Background: Surgical reconstruction of the earlobe after gauge ear piercing can be challenging especially in cases of large defects. Objective: By performing a systematic review of the current literature, we aimed to identify available surgical approaches for earlobe reconstruction after gauge piercing and provide a surgical classification system with regard to defect size. Methods: A literature review was performed including MEDLINE and PubMed databases to identify articles describing reconstruction after stretched earlobe piercing. Articles referring to traumatic, congenital, and acquired cleft deformities were excluded. Surgical techniques were summarized and categorized with regard to different defect sizes. Drawings of each method were performed. Results: A total of 17 different surgical approaches were found and described. Based on the authors' descriptions of each technique, a classification system for small to medium, large, and extralarge defects was established and special benefits of each method were highlighted. Conclusion: A simple classification of available techniques for stretched earlobe reconstruction with regard to defect size might help physicians to choose the appropriate surgical management especially in cases of large defects.

Suction Drain Volume following Axillary Lymph Node Dissection for Melanoma-When to Remove Drains? A Retrospective Cohort Study.

Postoperative complications such as seroma formation and wound-site infection occur following completion axillary lymph node dissection (ALND) for melanoma. We analyzed the impact of time-to-drain removal and drainage volume on seroma formation after ALND. We retrospectively analyzed data from 118 patients after completion ALND for melanoma. Primary endpoints were daily amount of drainage volume, seroma formation and time-to-drain removal. Secondary endpoints included patient-related, disease-specific and perioperative parameters as well as the number of histologically analyzed lymph nodes and surgical complications graded by the Clavien−Dindo classification (CDCL). Statistical analyses were performed using logistic regression models. Drain removal around the 8th postoperative day was statistically associated with a lower risk for the occurrence of seroma formation (p < 0.001). Patients with an increased drainage volume during the early postoperative days were more prone to develop seroma after drain removal. With 49% (CDCL I and II), most complications were managed conservatively, while only 5.9% (CDCL III) required revision surgery (CDCL overall: 55.9%). ALND is a safe procedure with a low rate of severe CDCL III type of complications. To decrease seroma evacuation, our results imply that drains should be removed around the 8th postoperative day to reduce the risk of infection, readmission or prolonged hospitalization.

The Impact of Antiseptic-Loaded Bacterial Nanocellulose on Different Biofilms-An Effective Treatment for Chronic Wounds?

Introduction: Pathogenic biofilms are an important factor for impaired wound healing, subsequently leading to chronic wounds. Nonsurgical treatment of chronic wound infections is limited to the use of conventional systemic antibiotics and antiseptics. Wound dressings based on bacterial nanocellulose (BNC) are considered a promising approach as an effective carrier for antiseptics. The aim of the present study was to investigate the antimicrobial activity of antiseptic-loaded BNC against in vitro biofilms. Materials and Methods: BNC was loaded with the commercially available antiseptics Prontosan® and Octenisept®. The silver-based dressing Aquacel®Ag Extra was used as a positive control. The biofilm efficacy of the loaded BNC sheets was tested against an in vitro 24-hour biofilm of Staphylococcus aureus and Candida albicans and a 48-hour biofilm of Pseudomonas aeruginosa. In vivo tests using a porcine excisional wound model was used to analyze the effect of a prolonged treatment with the antiseptics on the healing process. Results: We observed complete eradication of S. aureus biofilm in BNC loaded with Octenisept® and C. albicans biofilm for BNC loaded with Octenisept® or Prontosan®. Treatment with unloaded BNC also resulted in a statistically significant reduction in bacterial cell density of S. aureus compared to untreated biofilm. No difference on the wound healing outcome was observed for the wounds treated for seven days using BNC alone in comparison to BNC combined with Prontosan® or with Octenisept®. Conclusions: Based on these results, antiseptic-loaded BNC represents a promising and effective approach for the treatment of biofilms. Additionally, the prolonged exposure to the antiseptics does not affect the healing outcome. Prevention and treatment of chronic wound infections may be feasible with this novel approach and may even be superior to existing modalities.

Platelet-Rich Plasma in Plastic Surgery: A Systematic Review.

Introduction: Platelet-rich plasma (PRP) is gaining popularity and is applied in a variety of clinical settings. This review aims to present and evaluate available evidence regarding the use of PRP in various applications in plastic surgery. Methods: PubMed, Web of Science, Medline, and Embase were searched using predefined MeSH terms to identify studies concerning the application of PRP alone or in combination with fat grafting for plastic surgery. The search was limited to articles in English or German. Animal studies, in vitro studies, case reports, and case series were excluded. Results: Of 50 studies included in this review, eleven studies used PRP for reconstruction or wound treatment, eleven for cosmetic procedures, four for hand surgery, two for burn injuries, five for craniofacial disorders, and 17 as an adjuvant to fat grafting. Individual study characteristics were summarized. Considerable variation in preparation protocols and treatment strategies were observed. Even though several beneficial effects of PRP therapy were described, significance was not always demonstrated, and some studies yielded conflicting results. Efficacy of PRP was not universally proven in every field of application. Conclusion: This study presents an overview of current PRP treatment options and outcomes in plastic surgery. PRP may be beneficial for some indications explored in this review; however, currently available data are insufficient and systematic evaluation is limited due to high heterogeneity in PRP preparation and treatment regimens. Further randomized controlled trials employing standardized protocols are warranted.

Orchestrating the Dermal/Epidermal Tissue Ratio during Wound Healing by Controlling the Moisture Content.

A balanced and moist wound environment and surface increases the effect of various growth factors, cytokines, and chemokines, stimulating cell growth and wound healing. Considering this fact, we tested in vitro and in vivo water evaporation rates from the cellulose dressing epicitehydro when combined with different secondary dressings as well as the resulting wound healing efficacy in a porcine donor site model. The aim of this study was to evaluate how the different rates of water evaporation affected wound healing efficacy. To this end, epicitehydro primary dressing, in combination with different secondary dressing materials (cotton gauze, JELONET◊, AQUACEL® Extra ™, and OPSITE◊ Flexifix), was placed on 3 × 3 cm-sized dermatome wounds with a depth of 1.2 mm on the flanks of domestic pigs. The healing process was analyzed histologically and quantified by morphometry. High water evaporation rates by using the correct secondary dressing, such as cotton gauze, favored a better re-epithelialization in comparison with the low water evaporation resulting from an occlusive secondary dressing, which favored the formation of a new and intact dermal tissue that nearly fully replaced all the dermis that was removed during wounding. This newly available evidence may be of great benefit to clinical wound management.

Insulin induces a progressive increase in the resistance of subcutaneous tissue to fluid flow: Implications for insulin pump therapy.

AIM: To determine the effect of insulin on the resistance of subcutaneous tissue to the flow of infusion fluids. MATERIALS AND METHODS: Thirty subjects with type 1 diabetes wore two Accu-Chek Spirit Combo insulin pumps with Accu-Chek FlexLink infusion sets (Roche Diabetes Care, Mannheim, Germany) for 7 days. One pump was filled with insulin aspart (Novo Nordisk, Bagsvaerd, Denmark) and used for continuous subcutaneous insulin infusion (CSII). The other pump was filled with insulin diluting medium (IDM; Novo Nordisk) and used to deliver IDM subcutaneously at rates identical to those employed for CSII. Both infusion sites were assessed daily by measuring the pressure required to infuse various bolus amounts of IDM. RESULTS: On day 1, maximum pressure (Pmax ) and tissue flow resistance (TFR; calculated from measured pressure profiles) were similar for both infusion sites (P > 0.20). During the subsequent study days, the Pmax and TFR values observed at the IDM infusion site remained at levels comparable to those seen on day 1 (P > 0.13). However, at the site of CSII, Pmax and TFR progressively increased with CSII duration. By the end of day 7, Pmax and TFR reached 25.8 */2.11 kPa (geometric mean */geometric standard deviation) and 8.64 */3.48 kPa*s/µL, respectively, representing a remarkable 3.5- and 20.6-fold increase relative to the respective Pmax and TFR values observed on day 1 (P < 0.001). CONCLUSION: Our results suggest that insulin induces a progressive increase in the resistance of subcutaneous tissue to the introduction of fluid; this has important implications for the future design of insulin pumps and infusion sets.

Feasibility of collecting wound fluid during ongoing negative pressure wound therapy by the use of an additional container - A prospective observational study.

Negative-pressure-wound-therapy is commonly used in clinical routine for wound management. Aim of the present study was to assess the feasibility and safety of using an additional container to collect wound fluid during ongoing negative-pressure-wound-therapy. In this present prospective observational study, patients with negative-pressure-wound-therapy were included. An additional container was inserted in the connecting tube between the wound and the vacuum generating device. The following 3 days, the container was changed daily and replaced by a new one. Further safety outcome parameters were assessed. A questionnaire was answered by the responsible surgeon. Twenty-two patients with negative-pressure-wound-therapy with a median (IQR) age of 58.5 (53.0-70.0) years were included in the present study. In median, the duration of negative-pressure-wound-therapy was 5.0 (4.6-5.5) days. In mean ± SD the collected volume of the wound fluid in millilitres (mL) was on day one 7 ± 4 on day two 8 ± 7 and 10 ± 11 on day three. In one patient, there was <0.1 mL of clear water in the additional container. No safety concerns due to the additional container were observed. This study demonstrates that collecting wound fluid during ongoing negative-pressure-wound-therapy over a time period of 3 days is feasible and safe. No safety concerns were observed.

Thermal, Hyperspectral, and Laser Doppler Imaging: Non-Invasive Tools for Detection of The Deep Inferior Epigastric Artery Perforators-A Prospective Comparison Study.

Perforator flaps have become one of the leading procedures in microsurgical tissue transfer. Individual defects require a tailored approach to guarantee the most effective treatment. A thorough understanding of the individual vascular anatomy and the location of prominent perforators is of utmost importance and usually requires invasive angiography or at least acoustic Doppler exploration. In this study, we aimed at evaluating different non-invasive imaging modalities as possible alternatives for perforator location detection. After a cooling phase, we performed thermal, hyperspectral and Laser Doppler imaging and visually evaluated a possible detection of the perforator for a period of five minutes with an image taken every minute. We identified the most prominent perforator of the deep inferior epigastric artery by handheld acoustic Doppler in 18 patients. The detected perforator locations were then correlated. Eighteen participants were assessed with six images each per imaging method. We could show a positive match for 94.44%, 38.89%, and 0% of patients and 92.59%, 25.93%, and 0% of images for the methods respectively compared to the handheld acoustic Doppler. Sex, age, abdominal girth, and BMI showed no correlation with a possible visual detection of the perforator in the images. Therefore, thermal imaging can yield valuable supporting data in the individualized procedure planning. Future larger cohort studies are required to better assess the full potential of modern handheld thermal imaging devices.

Implementation status of morbidity and mortality conferences in Austrian hospitals-A cross-sectional national survey study.

INTRODUCTION: Morbidity and mortality conferences (M&MCs) are an instrument for learning from past complications, unexpected follow-ups and deaths in hospitals and are important for improving patient safety. However, there are currently no quantitative data on the implementation of M&MCs in Austria. The aim of the study was to determine the status quo of the M&MCs in Austria. MATERIALS AND METHODS: A national cross-sectional study was conducted by means of a survey of 982 chief physicians of surgical disciplines, internal medicine, anesthesiology, intensive care, gynecology/obstetrics and pediatrics. The questionnaire focused on overall goals, structure and procedures of hospital M&MCs. RESULTS: Of the 982 contacted chief physicians, 314 (32.0%) completed the survey. Almost two thirds of the respondents, i.e. 203 (64.7%), had already implemented M&MCs. Of the 111 chief physicians who had not yet introduced M&MCs, 62 (55.9%) were interested in introducing such conferences in the future. Of the 203 respondents that had implemented M&MCs, 100 stated that their M&MC could be improved. They reported issues with "shame and blame" culture, hierarchical structures, too little knowledge about the capability of M&MC and, in particular, time constraints. Overall, the participating chief physicians showed that they are striving to improve their existing M&MCs. DISCUSSION/CONCLUSION: While we found a relatively high number of already implemented M&MCs we also identified a large heterogeneity in the format of the M&MCs. A highly structured M&MC including guidelines, checklists or templates does not only considerably improve its outcome but can also alleviate the main limiting factor which is the lack of time.

Safe and Sufficient Glycemic Control by Using a Digital Clinical Decision Support System for Patients With Type 2 Diabetes in a Routine Setting on General Hospital Wards.

The aim was to investigate the applicability of a clinical decision support system in a real-world inpatient setting for patients with type 2 diabetes on general hospital wards.A total of 150 patients with type 2 diabetes requiring subcutaneous insulin therapy were treated with basal-bolus insulin therapy guided by a decision support system (GlucoTab) providing automated workflow tasks and suggestions for insulin dosing to health care professionals.By using the system, a mean daily blood glucose (BG) of 159 ± 32 mg/dL was achieved. 68.8% of measurements were in the target range (70 to <180 mg/dL). The percentage of BG values <40, <70, and ≥300 mg/dL was 0.02%, 2.2%, and 2.3%, respectively. Health care professionals' adherence to suggested insulin doses and workflow tasks was high (>93% and 91%, respectively).The decision support system facilitates safe and efficacious inpatient diabetes care by standardizing treatment workflow and providing decision support for basal-bolus insulin dosing.

Burns in pandemic times - The Graz way towards COVID-19 and back.

The first half of the year 2020 has been shaped by quarantines and lock-downs all over the world. The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a pandemic, that slowed down not only social interactions and economy, but also medical and health care. Governments and hospitals were forced to create ad hoc emergency plans maintaining the balance between an adequate participation in collective response of shutting-down to avoid a further spreading of the virus, while preserving the ongoing acute care and simultaneously being able to react to an imminent overextension with a collapse of capacities. The University Hospital Graz is one of the largest hospitals in Austria. As transregional trauma and burn centre it provides care for people from all over Austria and faced special challenges. We present the strategy of the University Hospital Graz in dealing with the COVID-19 pandemic and the way back to (new) normality. The strategy includes infrastructural, patient-centred and staff-centred measures. The continuously low numbers of new infections in Austria allowed a loosening of the lock-down measures already. Particular attention has to be paid to attentive screening of patients and triaging of surgeries during the re-boot. The re-boot needs to be slow and steady to reduce the risk of an infectiological relapse. Once this pandemic is defeated, a careful re-evaluation of the different internationally applied strategies should be performed to be prepared for the future.

Electrospun PCL/PLA Scaffolds Are More Suitable Carriers of Placental Mesenchymal Stromal Cells Than Collagen/Elastin Scaffolds and Prevent Wound Contraction in a Mouse Model of Wound Healing.

Mesenchymal stem/stromal cells (MSCs) exert beneficial effects during wound healing, and cell-seeded scaffolds are a promising method of application. Here, we compared the suitability of a clinically used collagen/elastin scaffold (Matriderm) with an electrospun Poly(ε-caprolactone)/poly(l-lactide) (PCL/PLA) scaffold as carriers for human amnion-derived MSCs (hAMSCs). We created an epidermal-like PCL/PLA scaffold and evaluated its microstructural, mechanical, and functional properties. Sequential spinning of different PCL/PLA concentrations resulted in a wide-meshed layer designed for cell-seeding and a dense-meshed layer for apical protection. The Matriderm and PCL/PLA scaffolds then were seeded with hAMSCs, with or without Matrigel coating. The quantity and quality of the adherent cells were evaluated in vitro. The results showed that hAMSCs adhered to and infiltrated both scaffold types but on day 3, more cells were observed on PCL/PLA than on Matriderm. Apoptosis and proliferation rates were similar for all carriers except the coated Matriderm, where apoptotic cells were significantly enhanced. On day 8, the number of cells decreased on all carrier types except the coated Matriderm, which had consistently low cell numbers. Uncoated Matriderm had the highest percentage of proliferative cells and lowest apoptosis rate of all carrier types. Each carrier also was topically applied to skin wound sites in a mouse model and analyzed in vivo over 14 days via optical imaging and histological methods, which showed detectable hAMSCs on all carrier types on day 8. On day 14, all wounds exhibited newly formed epidermis, and all carriers were well-integrated into the underlying dermis and showing signs of degradation. However, only wounds treated with uncoated PCL/PLA maintained a round appearance with minimal contraction. Overall, the results support a 3-day in vitro culture of scaffolds with hAMSCs before wound application. The PCL/PLA scaffold showed higher cell adherence than Matriderm, and the effect of the Matrigel coating was negligible, as all carrier types maintained sufficient numbers of transplanted cells in the wound area. The anti-contractive effects of the PCL/PLA scaffold offer potential new therapeutic approaches to wound care.

Delivery of antiseptic solutions by a bacterial cellulose wound dressing: Uptake, release and antibacterial efficacy of octenidine and povidone-iodine.

BACKGROUND: Bacterial nanocellulose (BNC) is considered a promising carrier for various substances and novel approaches using BNC in combination with antiseptics are well documented. However, the difference in the molecular weight of these molecules influences their uptake by and release from BNC. Analysing the diffusion of standard molecules with different weight, e.g. dextrans, offers the possibility to investigate the mobility of various molecules. We aimed to test the use of BNC regarding uptake and release of different standard molecules as well as two commercially available antiseptics for possible applications in future wound dressings. MATERIAL AND METHODS: Diffusion profiles, uptake and release of three FITC-dextran molecules differing in weight as well as octenidine (Octenisept®) and povidone-iodine (Betaisodona®)-based antiseptics were tested with BNC-based wound dressings. Furthermore, the antiseptic efficacy of BNC in combination with antiseptics against Staphylococcus aureus was tested. RESULTS: Uptake and release capacity for FITC-dextran molecules showed a molecular weight-dependent mobility from BNC into an agarose gel. The loading capacity of BNC was also inversely proportional to the molecular weight of the antiseptics. The release test for octenidine showed a sustained and prolonged delivery into a solid matrix, whereas povidone-iodine was released faster. Both antiseptic solutions combined with BNC showed a good dose-dependent efficacy against S. aureus. CONCLUSION: Results obtained from the mobility of FITC-dextran molecules in the BNC matrix could open possible applications for the combination of BNC with other molecules for medical applications. Combination of both tested antiseptics with BNC showed to be an efficient approach to control bacterial infections.