Scar Maturation Research Articles

The effects of valsartan on scar maturation in an experimental rabbit ear wound model

Introduction In our study, we aimed to search and compare the effects of valsartan and enalapril on the pathological scar formation on the basis of histomorphological parameters. Materials and Methods Nine New Zealand albino male rabbits, which were divided into three groups, were included in the study. A previously described rabbit ear wound model was used. Enalapril was administered 0.75 mg/kg/day on the first group and valsartan was administered 10 mg/kg/day on the second group for 40 days. The third group was the control group. Results were evaluated on the 40th day with scar elevation index calculation and histological studies. Histological studies were done by using Hematoxylin-eosin, Masson trichrome and Sirius Red stains. Results Enalapril and valsartan groups were both significantly effective on the prevention of pathological scar formation when compared to the control group in terms of fibroblast count, capillary count, type 1/3 collagen ratio, collagen organization, and epithelial thickness. There was no significant difference between the enalapril and control group on the scar elevation index. Valsartan group was more efficient than the enalapril group on the reduction of fibroblast count and epithelial thickness. Conclusion Both Valsartan and Enalapril are found to be effective for the prevention of pathological scar formation.

Topical Scar Treatment Products for Wounds: A Systematic Review.

There is an increasing number of over-the-counter topical products that are said to prevent pathologic scar formation and improve scar cosmesis. However, robust clinical data are lacking to substantiate these claims and to guide selection of topical products. To determine the effectiveness of topical scar management products, including silicone gel, Allium cepa onion extract, vitamin E, trolamine, and microporous tape. A PubMed search (2005-2019) was performed to identify studies of topical scar management products. Randomized controlled trials (RCTs), quasi-RCTs, meta-analyses, and controlled clinical trials were included for analysis. A total of 34 trials were included in this study. Of the 16 trials investigating silicone gel sheets, numerous high-quality RCTs found that silicone gel sheets and silicone gels significantly improved scar outcomes. Only a limited number of studies supported the effectiveness of onion extract, vitamin E, trolamine, and microporous tape products. Silicone gel products are an effective noninvasive treatment to prevent formation of pathologic scars and improve mature scars. Further high-quality studies are needed to elucidate the long-term effectiveness of these therapies.

Fractionated Ablative Carbon Dioxide Laser Therapy Decreases Ultrasound Thickness of Hypertrophic Burn Scar: A Prospective Process Improvement Initiative.

Carbon dioxide (CO2) laser treatment is routinely used to treat hypertrophic burn scars (HBS). Although prior research has documented subjective improvement in HBS after treatment, there is little data evaluating objective changes in scar characteristics after therapy. The aim of our process improvement project was to evaluate changes to scar thickness (ST) using high-frequency ultrasound in patients with HBS undergoing CO2 laser therapy. Ultrasound measurements of ST were obtained from patients with HBS before initial and at each subsequent treatment. ST, reduction in ST per treatment, and percentage reduction in ST from baseline were tabulated. Post hoc analyses examining the effect of initial ST and scar maturity on outcome were performed. First, patients were grouped by baseline ST into thicker (group 1, initial ST ≥ median value) and thinner (group 2, initial ST < median value) scar groups. Second, patients were divided into quartiles based on time from injury to treatment. Outcomes at each time point were compared with either Mann-Whitney U or Kruskal-Wallis tests, with Bonferonni corrections performed for post hoc subgroup analyses. Significance was set at P < 0.05. Twenty-one consecutive patients with HBS treated with CO2 laser were included. All patients completed 1 or more treatment, 48% completed 2 or more treatments, and 28% completed 3 treatments. Median initial ST was 0.71 cm (0.44-0.98 cm), and median scar maturity was 7.5 months (4.9-9.8 months). Overall, ST decreased over the treatment course (P < 0.001), with post hoc analysis demonstrating that 2 treatments were required to achieve a significant ST reduction (P < 0.01). On subgroup analysis comparing initial ST, ST decreased significantly in group 1 (thicker scars) overall (P < 0.001) but not in group 2 (P = 0.109). ST reduction was greatest after 1 treatment in group 1 (P = 0.022) and group 2 (P = 0.061). Percent reduction was greater in group 1 relative to group 2 after 1 treatment (P = 0.016). On subgroup analysis of scar maturity, there were no significant differences in either baseline ST or ST at any subsequent visit. Fractionated ablative CO2 laser treatment improved ST after 1 to 2 treatments. Patients with thicker scars demonstrated greater ST reduction than those with thinner scars. Ultrasound adequately assessed treatment response.

Loading To Optimize Patellar Tendon Repair After Injury

PURPOSE: Tendinopathy is one of the most common musculoskeletal issues in jumping sports. In sports like basketball and volleyball, tendinopathy rates reach greater than 45%. Interventions to prevent or treat tendinopathies would improve an athlete’s quality of life and team performance. The goal of any intervention to treat tendinopathy is to increase the content of directionally oriented collagen, decrease pain, and increase the tensile strength of the tendon. This study is designed to determine the molecular changes that promote tendon repair. METHODS: Patellar tendon injury was induced in male Wistar Rats with a 2mm biopsy punch. Rats then recovered with normal cage activity for 15 days to allow a mature scar to form. Following scar formation, groups received either an isometric load (4 x 30 second contraction, 2 min rest) or an equivalent time under tension using dynamic loads (360 contractions lasting 333ms each). The injured region of the tendon was collected 18 hrs after loading and immediately frozen. RNA was isolated from the tendon for RT-qPCR determination of genes involved in tendon (collagen I, III, lysyl oxidase, and scleraxis) and fibrocartilage (collagen II, aggrecan, tenascin C, and Sox9) formation. RESULTS: Tendon scar formation was confirmed by visual inspection. The injured region showed increased vascularity and greater volume. Our preliminary findings suggest that RNA within the tendon increases from 154.4±20.5μg at baseline to 497.9±128.1μg two weeks after injury. Acute isometric exercise of the scarred tendon decreased RNA in the injured region slightly to 341.1±16.8μg. At the time of submission the gene expression studies are being completed. CONCLUSIONS: This pilot study confirms that following injury there is an increase in cell mass (greater RNA) in the scar. Further work on the expression of tendon and cartilaginous genes within the scar will help with the development of a loading program to repair patellar tendinopathy.

Inflammation shapes pathogenesis of murine arrhythmogenic cardiomyopathy

Arrhythmogenic cardiomyopathy (AC) is an incurable genetic disease, whose pathogenesis is poorly understood. AC is characterized by arrhythmia, fibrosis, and cardiodilation that may lead to sudden cardiac death or heart failure. To elucidate AC pathogenesis and to design possible treatment strategies of AC, multiple murine models have been established. Among them, mice carrying desmoglein 2 mutations are particularly valuable given the identification of desmoglein 2 mutations in human AC and the detection of desmoglein 2 auto-antibodies in AC patients. Using two mouse strains producing either a mutant desmoglein 2 or lacking desmoglein 2 in cardiomyocytes, we test the hypothesis that inflammation is a major component of disease pathogenesis. We show that multifocal cardiomyocyte necrosis initiates a neutrophil-dominated inflammatory response, which also involves macrophages and T cells. Increased expression of Ccl2/Ccr2, Ccl3/Ccr5, and Cxcl5/Cxcr2 mRNA reflects the observed immune cell recruitment. During the ensuing acute disease phase, Mmp12+ and Spp1+ macrophages and T cells accumulate in scars, which mature from cell- to collagen-rich. The expression of Cx3cl1/Cx3cr1, Ccl2/Ccr2, and Cxcl10/Cxcr3 dominates this disease phase. We furthermore find that during chronic disease progression macrophages and T cells persist within mature scars and are present in expanding interstitial fibrosis. Ccl12 and Cx3cl1 are predominant chemokines in this disease phase. Together, our observations provide strong evidence that specific immune cell populations and chemokine expression profiles modulate inflammatory and repair processes throughout AC progression.

Randomised Control Clinical Trial of Topical Silicone Gel in Post-Lower Segment Caesarean Section Closure scar in Primigravida

Scar following caesarean section surgery is an important aspect affecting aesthetics and function in young ladies. This study was done to compare the effectiveness of scar modulation using topical silicone gel in post-lower segment caesarean section scar in primigravida. Case series analysis was conducted between 01 Jul 2018 and 30 Jun 2019 in a tertiary care centre. Post-lower segment caesarean section scars in 52 primigravida were randomised into 2 groups. Group A used topical silicone gel once daily for 3 min of massage. Group B had normal natural scar maturation without any intervention. Observational data collected and photographs were taken at 2 weeks, 4 weeks and 12 weeks. Vancouver scar score used to assess observed data and result compiled. Topical silicone gel gave superior results in reducing overall scar quality at 1 month and 3 months. Topical silicone gel was a superior product for initial management of caesarean scars.

Neutrophils Modulate Fibroblast Function and Promote Healing and Scar Formation after Murine Myocardial Infarction.

Aim: Recruitment of neutrophils to the heart following acute myocardial infarction (MI) initiates inflammation and contributes to adverse post-infarct left ventricular (LV) remodeling. However, therapeutic inhibition of neutrophil recruitment into the infarct zone has not been beneficial in MI patients, suggesting a possible dual role for neutrophils in inflammation and repair following MI. Here, we investigate the effect of neutrophils on cardiac fibroblast function following MI. Methods and Results: We found that co-incubating neutrophils with isolated cardiac fibroblasts enhanced the production of provisional extracellular matrix proteins and reduced collagen synthesis when compared to control or co-incubation with mononuclear cells. Furthermore, we showed that neutrophils are required to induce the transient up-regulation of transforming growth factor (TGF)-ß1 expression in fibroblasts, a key requirement for terminating the pro-inflammatory phase and allowing the reparatory phase to form a mature scar after MI. Conclusion: Neutrophils are essential for both initiation and termination of inflammatory events that control and modulate the healing process after MI. Therefore, one should exercise caution when testing therapeutic strategies to inhibit neutrophil recruitment into the infarct zone in MI patients.

Dexamethasone inhibits regeneration and causes ventricular aneurysm in the neonatal porcine heart after myocardial infarction

AimsRecently, we demonstrated that the hearts of neonatal pigs (2-day old) have regenerative capacity, likely driven by cardiac myocyte division, but this potential is lost immediately after postnatal day 3. However, it is unknown if corticosteroid, a broad anti-inflammatory agent, will abrogate the regenerative capacity in the hearts of neonatal pigs. The aim of the current study is to evaluate the effect Dexamethasone (Dex), a broad anti-inflammatory agent, on heart regeneration, structure, and function of the neonatal pigs' post-myocardial infarction (MI). Methods and resultsDex (0.2 mg/kg/day) was injected intramuscularly into the neonatal pig (age: 2 days postnatal) during the first week post-MI. Myocardial scar and left ventricular function were determined by cardiac magnetic resonance (CMR) imaging. Bromodeoxyuridine (BrdU) pulse-chase labeling, histology, immunohistochemistry, and flow cytometry were performed to determine inflammatory cell infiltration, CM cytokinesis, and myocardial fibrosis. Dex injection during the first-week suppressed acute inflammation post-MI in the pig hearts. It inhibited BrdU incorporation to pig CMs and CM cytokinesis via inhibiting aurora-B protein expression which was associated with mature scar formation and thinned walls at the infarct site. CMR imaging showed Dex caused left ventricular aneurysm and poor ejection fraction. ConclusionsDex inhibited CM cytokinesis and functional recovery and caused ventricular aneurysm in the hearts of 2-day old pigs post-MI.

Transection of the medial meniscus anterior horn results in cartilage degeneration and meniscus remodeling in a large animal model.

The meniscus plays a central load-bearing role in the knee joint. Unfortunately, meniscus injury is common and can lead to joint degeneration and osteoarthritis (OA). In small animal models, progressive degenerative changes occur with the unloading of the meniscus via destabilization of the medial meniscus (DMM). However, few large animal models of DMM exist and the joint-wide initiation of the disease has not yet been defined in these models. Thus, the goal of this study is to develop and validate a large animal model of surgically induced DMM and to use multimodal (mechanical, histological, and magnetic resonance imaging) and multiscale (joint to tissue level) quantitative measures to evaluate degeneration in both the meniscus and cartilage. DMM was achieved using an arthroscopic approach in 13 Yucatan minipigs. One month after DMM, joint contact area decreased and peak pressure increased, indicating altered load transmission as a result of meniscus destabilization. By 3 months, the joint had adapted to the injury and load transmission patterns were restored to baseline, likely due to the formation and maturation of a fibrovascular scar at the anterior aspect of the meniscus. Despite this, we found a decrease in the indentation modulus of the tibial cartilage and an increase in cartilage histopathology scores at 1 month compared to sham-operated animals; these deleterious changes persisted through 3 months. Over this same time course, meniscus remodeling was evident through decreased proteoglycan staining in DMM compared to sham menisci at both 1 and 3 months. These findings support that arthroscopic DMM results in joint degeneration in the Yucatan minipig and provide a new large animal testbed in which to evaluate therapeutics and interventions to treat post-traumatic OA that originates from a meniscal injury.

74 The Effectiveness of Serial Casting in Obtaining Maximum Range in Burn Scar Contracted Joints

Abstract Introduction Recovery from burn scar contracture demands significant time and resources from patients and healthcare providers. Few studies have explored how serial casting improves recovery. The aim is to present preliminary data illustrating the benefits of serial casting in burn scar contracture rehabilitation. Methods Six burn patients (8 joints) that did not respond to traditional conservative therapy were included. Joints were x-rayed to rule out heterotopic ossification/joint abnormality before casting. Patients were casted 5x, 3x or 1x/week. Initial session consisted of measuring baseline range of motion (ROM) prior to physiotherapy intervention (PTI) (heat, active ROM with end range overpressure, joint glides, and progressive resistive exercises) and plaster cast application by Occupational Therapy. Following sessions involved measuring ROM post cast removal, and before PTI and new cast application. Scar contractures were photographed weekly and assessed using the Modified Vancouver Scar Scale (MVSS). Results On average, casting started 93.67±20.31 days post burn injury and lasted 8.90±1.23 days. Mean time between cast changes was 2.30±0.25 days; on average, each joint was casted 4.30±0.65 times. MVSS score (pre/post serial casting:9.70±0.47 / 4.70±0.42, p&amp;lt; 0.0001) and ROM as a percentage of total (pre/post serial casting:56.30±5.12% / 96.40±0.90%, p&amp;lt; 0.0001) showed improvements from pre to post casting. Post casting, average ROM gained was 43.70±6.60 degrees and average percentage of ROM regained was 96.38±0.87%. Each joint consumed a mean of 6.56±1.22 therapy hours and $45.13±12.15 in materials. Conclusions Serial casting produced rapid gains in ROM to near full ROM in burn scar contracted joints. Correspondingly scar pliability, height, and pigmentation improved. Serial casting can be effective and initiated early in scar maturation. Applicability of Research to Practice Serial casting can be a standard technique in rehabilitation of burn scar contracture. It is easy to adopt due to low material cost, easy therapist training, and low time demands from patients and therapists. It can delay or prevent the need for contracture release surgery (in the case of 3 patients). Based on therapist observations, it can lead to increased treatment compliance due to rapid effectiveness.

111 Predicting Restoration of Joint Function in the Contracted Burned Hand: The Benefit of the Soft Tissue to Skeletal Ratio

Abstract Introduction Long-standing burn contractures of the hand produce marked soft tissue deficits across mobile joint surfaces. Optimum functional reconstruction requires attention to the ratio of soft tissue contracture to skeletal length. Maturation of burn scar and anticipated growth in children play a role in selecting procedures that maximize function and range. Methods Burn contractures of the hand show functional loss of motion by flexion/extension deformities of the fingers and wrist. Analysis of soft tissue shortening (contraction), measured against existing skeletal length was used to customize procedures to restore maximum function. Twenty six patients, aged 3 to 57 years underwent post burn reconstruction to maximize hand function. Each procedure selected was based on the ratio of existing soft tissue to skeletal length. Results Flexion/extension at all joints requires a balanced glide of soft tissue over existing bone length defining a 1:1 ratio between soft tissue and skeletal length. Burn contracture shortens soft tissue and restricts motion over joints. An objective ratio was applied to each joint contracture. A comparison of soft tissue quality to skeletal length (including growth in children) was used to determine the procedure for reconstruction associated with the best prognosis for maximum outcome with the least recurrence. Abnormalities included post burn boutonniere deformities, webspace contractures, flexion and extension contracture deformities of the hand, and digits. Burn scar hypertrophy and induration worsened the ratio. Eight patients with a soft tissue to skeletal ratio of 0.4:1 or less required bone shortening in the form of either joint arthrodesis, trapeziectomy, or wrist fusion. Twelve patients with a ratio of 0.7:1 or better were managed with skin grafts and/or adjacent tissue rearrangement. In the remaining group, four patients required a combination of procedures including composite soft tissue and tendon expansion restoring length of all soft tissue relative to bony length precluding the need for flap reconstruction and tendon lengthening. Two patients underwent bone shortening with prosthetic joint replacement. All patients restored to a 0.8:1 ratio or better regained optimum position of joint position and function. No secondary procedures were required for deterioration of function at two years. Conclusions A balanced dynamic soft tissue to skeletal ratio is essential in restoring maximum function to the burned hand. Understanding soft tissue contraction compared to existing bone length will permit the objective design of a reconstructive hand/finger procedure that will predict outcome and maximize hand function. Applicability of Research to Practice Predicable outcomes of functional hand reconstruction are possible based on the relationship of burn scar contracture to measurable skeletal length.

638 Auricular Splinting Following Severe Facial Burn Injury and Reconstruction

Abstract Introduction With a severe facial burn, injury often involves the ear(s) resulting in damage or loss which may require reconstruction. In consideration of the functional and psychological effect that loss of a defined ear lobe may entail, reconstruction is an important consideration for the burn survivor. Two cases described in detail with illustration will highlight an auricular contracture release; one with V-Y Advancement and the other with a transposition flap. Preservation of the auricular reconstruction is accomplished by implementing necessary splinting. The auricular splint fabricated was made from a combination of silicone and low-temperature thermoplastic material. A step-by-step process will illustrate the needed materials and techniques to fabricate a worthy splint in order to preserve what was surgically achieved. The splint maintains the space between the ear and head to properly position and prevent contracture through the healing and scar maturation process. It secured with a one-inch head band that is sublime enough to foster compliance with wear. The auricular splint material also serves as scar management with the many proven benefits of silicone. Methods Two case studies are reviewed with auricular contractures that required release and reconstruction. The auricular splints were fabricated to stabilize and preserve the reconstructed ear lobe. The wear schedule was intermittent during the day and overnight in combination with scar massage. The patients reported good compliance with wear and stability of splint position with overnight wear. Skin integrity was not compromised with overnight or intermittent wear. The splint fabrication process is reviewed and illustrated with a simplistic innovative end result that is user friendly. Results Surgical reconstruction was required following development of auricular contractures and partial loss. With post-operative bandage removal and wound closure, positioning was a necessary consideration to preserve post-surgical reconstruction. Conclusions In conclusion, the peri-auricular splint is fabricated with low temperature splinting material lined in silicone proved worthy for effective positioning and reported comfort with wear. Effective splinting is necessary for the preservation of surgical reconstruction and to prevent contracture from sabotaging surgical efforts. Applicability of Research to Practice Consideration of fabrication of silicone auricular splints to preserve the accomplishments of auricular surgical reconstruction.

3D-structural change of nasopharynx following adenoidectomy: 10-year serial data in a single hospital.

Scar contracture commonly refers to decreased function in the scar area, whereas scar contraction refers to shortening of the scar length compared to the original wound. Wound scar remodeling occurs during months to years of wound healing to form a mature scar. Serial reports about patients who had undergone adenoidectomy are rare. Thus, the objective of this study was to evaluate some parameters of air way passage in patients who had undergone post adenoidectomy. Data of patients who have undergone adenoidectomy between 2000 and 2002 in our hospital were obtained. A total of 154 head and neck CT scans from an adenoidectomy group and a control group were analyzed. We measured lengths of several areas, including the width of posterior wall of nasopharynx, the widest diameter in the upper air way, the length between both Eustachian tubes, the length between both pharyngeal recesses, and the anterior to posterior diameter of the nasopharynx. This study was approved by Institutional Review Board (IRB) of the Department of Otolaryngology Head and Neck Surgery of Catholic University (approval number: UC18RESI0130). There were significant differences in the following parameters between the two groups: the width of posterior wall of nasopharynx and the length between both pharyngeal recesses. Extensive removal of soft tissue or injured muscle layer during surgery might be one of the reasons for the narrowing of airway. Keeping in mind not to make much injury the soft tissue or muscles during adenoidectomy is very important for the long-term outcome of this surgery.

Principles of Cell Circuits for Tissue Repair and Fibrosis.

SummaryTissue repair is a protective response after injury, but repetitive or prolonged injury can lead to fibrosis, a pathological state of excessive scarring. To pinpoint the dynamic mechanisms underlying fibrosis, it is important to understand the principles of the cell circuits that carry out tissue repair. In this study, we establish a cell-circuit framework for the myofibroblast-macrophage circuit in wound healing, including the accumulation of scar-forming extracellular matrix. We find that fibrosis results from multistability between three outcomes, which we term “hot fibrosis” characterized by many macrophages, “cold fibrosis” lacking macrophages, and normal wound healing. This framework clarifies several unexplained phenomena including the paradoxical effect of macrophage depletion, the limited time-window in which removing inflammation leads to healing, and why scar maturation takes months. We define key parameters that control the transition from healing to fibrosis, which may serve as potential targets for therapeutic reduction of fibrosis.

Retki penilni keloidi nakon cirkumcizije - prikaz slučaja i pregled literature

Abstract: Objective: To report a case of keloid formation after circumcision and review the literature for similar cases to formulate possible risk factors contributing to its development as well as its treatment options. Method: a literature review was done using PubMed and Google Scholar by searching the keyword "keloid", "penis" and "circumcision". Additional searches were done on references from related articles. The articles are then reviewed by the author, noting for possible predisposing factors to keloid formation, along with patient demographics and method of treatments. Findings were then tabulated and analyzed using Microsoft Excel (2018). Results: Thirteen case reports on penile keloid after circumcision with a total of 16 patients were found dating from 1993 to 2017. Circumcision in four cases (25%) were complicated with infection or dehiscence. The median age during circumcision is 9 years old. Two patients (12.5%) were reported with the tendency for keloid. The ethnicity of the patients is as follows; Turkish (7 cases, 43.7%), African descent (4 cases, 25%), Chinese (3 cases, 18.75%), Indian (1 case 6.25%) and Caucasian (1 case, 6.25%). Ten (62.5%) cases were treated with a combination of excision and immediate injection of triamcinolone acetate. Others were treated with either excision alone, steroid injection alone or excision with topical steroid. Maintenance treatment includes topical steroid, intralesional injection of steroid, and silicone gel. Recurrence occurred in one patient. Conclusion: The minuscule number of published reports of keloid formation after circumcision underscores the rarity of the complication. No specific risk factors can be attributed to stratify patients who may develop keloid after circumcision. Excision followed by triamcinolone acetate injection with maintenance therapy until scar maturity is the preferred choice of treatment for penile keloid.

Evaluation of wound healing effect of alginate film containing Aloe vera gel and cross-linked with zinc chloride.

Purpose To develop a new wound dressing composed of alginate and Aloe vera gel and cross-linked with zinc ions.Methods The aloe-alginate film was characterized using scanning electron microscopy (SEM), swelling profile, mechanical properties, polysaccharide content and X-ray diffraction (XRD). Thirty Wistar rats were divided in two groups a) treated with aloe-alginate film and b) control (treated with sterile gauze). Wound contraction measurements and hystological analysis were performed on 7th, 14th and 21st days after wound surgery.Results The aloe-alginate film presented adequated mechanical resistance and malleability for application as wound dressing. There was no statistical difference in wound contraction between two groups. Histological assay demonstrated that aloe-alginate film presented anti-inflammatory activity, stimulated angiogenesis on proliferative phase and a more significant increased in collagen type I fibers and decreased type III fibers which promoted a mature scar formation when compared to control.Conclusions The aloe-alginate film showed adequate physicochemical characteristics for wound dressing applications. The in vivo assay demonstrated that aloe-alginate film enhanced the healing process of incisional skin wounds.

Functional Reconstruction of Post-Burn Hand Contractures

Most patients who have survived severe burn injury may not have truly escaped the aftermath of severe scars which is post burn contractures. Hands are one of the most prevalent site of burn injury leading to contractures, which are important in terms of function and cosmesis. There is great deal of functional limitation, whereof contractures in both hands can make a burn survivor a total cripple. Moreover poor cosmetic result must also be considered as it gives impact towards patient’s self-esteem and quality of life. Treatment algorithm must be based on clinical presentation and severity of range of motion. Release of contracture, wound resurfacing and choice of reconstructive procedures must be based on timing of scar maturity as well as through a case-by case approach.

Parenchymal pericytes are not the major contributor of extracellular matrix in the fibrotic scar after stroke in male mice.

Scar formation after injury of the brain or spinal cord is a common event. While glial scar formation by astrocytes has been extensively studied, much less is known about the fibrotic scar, in particular after stroke. Platelet‐derived growth factor receptor ß‐expressing (PDGFRß+) pericytes have been suggested as a source of the fibrotic scar depositing fibrous extracellular matrix (ECM) proteins after detaching from the vessel wall. However, to what extent these parenchymal PDGFRß+ cells contribute to the fibrotic scar and whether targeting these cells affects fibrotic scar formation in stroke is still unclear. Here, we utilize male transgenic mice that after a permanent middle cerebral artery occlusion stroke model have a shift from a parenchymal to a perivascular location of PDGFRß+ cells due to the loss of regulator of G‐protein signaling 5 in pericytes. We find that only a small fraction of parenchymal PDGFRß+ cells co‐label with type I collagen and fibronectin. Consequently, a reduction in parenchymal PDGFRß+ cells by ca. 50% did not affect the overall type I collagen or fibronectin deposition after stroke. The redistribution of PDGFRß+ cells to a perivascular location, however, resulted in a reduced thickening of the vascular basement membrane and changed the temporal dynamics of glial scar maturation after stroke. We demonstrate that parenchymal PDGFRß+ cells are not the main contributor to the fibrotic ECM, and therefore targeting these cells might not impact on fibrotic scar formation after stroke.

Innovations in skin camouflaging techniques: Where are we scientifically?

Cutaneous disorders can impact on the psycho-social well-being of children and adults alike, which has been reviewed elsewhere (Body Image 27, 2018 and 98). The present review sets out to evaluate progressions in skin masking and camouflaging techniques together with evaluating the efficacy of these. There does not appear to have been any recent reviews about innovations in skin camouflaging techniques. Using the National Centre for Biotechnology Information PubMed database, a search was made for all studies published between 2000 and 2019 that met defined inclusion criteria. A total of seven relevant publications were identified. Of the seven studies identified, skin camouflaging improved quality of life in three studies and reduced anxiety, depression and social isolation in others. Of the camouflaging methods used, liquidized simulated second skin technology (Microskin™) appears to look particularly promising. This method of colour matching and a spray/stippling application uses a technology that binds to the epidermis of the skin helping to overcome previous concerns about the colour, coverage and application of camouflage and masking bases. Two studies showed that this innovative mode of camouflaging raised confidence, feelings of happiness and social experiences in children and adolescents with burn scarring. Very few studies reported drawbacks of camouflaging techniques, with limited colour matches and 'itching' appearing to be the main shortcomings. New technologies now appear to be addressing these. Results show that there is wide variation in the quality and modes of skin camouflaging. Of the methods used, simulated second skin technology appears to be an important and effective therapy for individuals with cutaneous skin disorders. Training schemes along with increased awareness of this technique must now be communicated to medical professionals who come into contact with children and adults who could benefit physically, psychologically and socially from this therapy.

Scarring and wound healing.

Following injury, the skin undergoes a wound healing process culminating in the formation of a mature scar. Millions of patients worldwide are left with scars every year as a result of trauma or surgery. Scars can be painful, disfiguring and disabling, yet patients report that clinicians are often dismissive of their concerns, unable to identify pathological scars and unaware of treatment options. The normal wound healing process comprises three overlapping stages: inflammation, proliferation and remodelling. In some patients this process is deranged, resulting in the formation of hypertrophic or keloid scars. Clinicians can minimize the risk of these pathological scars developing with good surgical technique and wound aftercare. If pathological scars do form, they should be identified early and patients referred for treatment, most often topical or intralesional corticosteroids. In resistant cases, pathological scars may be treated with phototherapy, radiotherapy or surgical resection.