Genetic susceptibility to raised dermal scarring

Presentation, Management, and Outcomes of Pathologic Scars Within a Pediatric Otolaryngology Practice

OBJECTIVES

This study aims to review the spectrum of scarring that may present to an urban, pediatric otolaryngology practice and determine if associations exist between race, scar location, treatment modality, and outcomes following interventions for scarring.

METHODS

Retrospective cohort study among 115 pediatric patients with 138 unique keloids or hypertrophic scars (HTS), and 141 children presenting for tonsillectomy at Tufts Medical Center. Age at presentation and sex assigned at birth were collected for both populations. For those presenting for pathologic scars, income quintile, self-identified race/ethnicity, anatomical location, treatment number and type, and clinical outcome were also analyzed. Multivariate analyses calculated adjusted odds ratios (aORs) and 95% confidence intervals to assess associations between scar subsite, intervention type, and persistence after treatment.

RESULTS

Compared to individuals presenting for tonsillectomy, a disproportionate percentage of patients presenting for scarring identified as Black (26.6% vs. 13.5%) or Asian (17.4% vs. 7.1%, p = 0.016) or were male (61.7% vs. 49.7%, p = 0.053). Individuals identifying as Black or Asian were more likely to present with ear lobe and neck scars, respectively (50.0% vs. 45.5%, p = <0.001). Ear scars were significantly more likely to receive excision at initial treatment (aOR = 5.86 [1.43-23.96]) compared to other subsites, and were more likely to require >1 treatment (aOR = 5.91 [1.53-22.75]).

CONCLUSION

Among pediatric patients presenting with keloids or HTS, children who identified as Black or Asian were more likely to present with ear and neck scars, respectively. Ear scars were frequently treated with excision and appear more likely to require adjuvant treatments and multiple interventions.

LEVEL OF EVIDENCE

3 Laryngoscope, 134:3127-3135, 2024.

Genetic influence on scar vascularity after burn injury in individuals of European ancestry: A prospective cohort study

After burn injury there is considerable variation in scar outcome, partially due to genetic factors. Scar vascularity is one characteristic that varies between individuals, and this study aimed to identify genetic variants contributing to different scar vascularity outcomes. An exome-wide array association study and gene pathway analysis was performed on a prospective cohort of 665 patients of European ancestry treated for burn injury, using their scar vascularity (SV) sub-score, part of the modified Vancouver Scar Scale (mVSS), as an outcome measure. DNA was genotyped using the Infinium HumanCoreExome-24 BeadChip, imputed to the Haplotype Reference Consortium panel. Associations between genetic variants (single nucleotide polymorphisms) and SV were estimated using an additive genetic model adjusting for sex, age, % total body surface area and number of surgical procedures, utilising linear and multinomial logistic regression. No individual genetic variants achieved the cut-off threshold for significance. Gene sets were also analysed using the Functional Mapping and Annotation (FUMA) platform, in which biological processes indirectly related to angiogenesis were significantly represented. This study suggests that SNPs in genes associated with angiogenesis may influence SV, but further studies with larger datasets are essential to validate these findings.

Paper Tape May Improve Scar Aesthetics and Prevent Wound Closure Complications

There is uncertainty whether postoperative application of paper tape (PT) improves scar aesthetics and reduces wound closure complications. This study aimed to review and assess the quality of applicable findings from studies investigating PT's efficacy. We queried PubMed and SCOPUS using the search terms "(("paper tape") AND (wound OR closure OR heal* OR complication OR skin OR prevent* OR scar*))." We excluded articles that were duplicates, basic science, or not clinically relevant. We assessed the level of evidence for each article using the American Society of Plastic Surgeons (ASPS) Rating Levels of Evidence and Grading Recommendations for Therapeutic Studies, ranging from I (highest) to V (lowest). Of 186 publications reviewed, we included eight studies in the literature review. Five of these studies reported statistically significant positive outcomes on scar aesthetics and wound closure associated with using PT. Using the ASPS rating system, we found that two studies were Level I, three studies were Level II, two studies were Level IV, and one study was Level V. Notably, heterogeneity in the study designs limited outcome comparison. The data from the studies included in this literature review support using PT to optimize scar and wound management. The lack of higher levels of evidence, however, suggests the need for additional randomized controlled trials to rigorously evaluate patient outcomes when using PT compared with other forms of adhesive dressings.

Scars

Wound healing occurs as a response to disruption of the epidermis and dermis. It is an intricate and well-orchestrated response with the goal to restore skin integrity and function. However, in hundreds of millions of patients, skin wound healing results in abnormal scarring, including keloid lesions or hypertrophic scarring. Although the underlying mechanisms of hypertrophic scars and keloid lesions are not well defined, evidence suggests that the changes in the extracellular matrix are perpetuated by ongoing inflammation in susceptible individuals, resulting in a fibrotic phenotype. The lesions then become established, with ongoing deposition of excess disordered collagen. Not only can abnormal scarring be debilitating and painful, it can also cause functional impairment and profound changes in appearance, thereby substantially affecting patients' lives. Despite the vast demand on patient health and the medical society, very little progress has been made in the care of patients with abnormal scarring. To improve the outcome of pathological scarring, standardized and innovative approaches are required.

Mimicking fat grafting of fibrotic scars using 3D-organotypic skin cultures

Wound healing of deep burn injuries is often accompanied by severe scarring, such as hypertrophic scar (HTS) formation. In severe burn wounds, where the subcutis is also damaged, the scars adhere to structures underneath, resulting in stiffness of the scar and impaired motion. Over the recent years, a promising solution has emerged: autologous fat grafting, also known as lipofilling. Previous clinical reports have shown that the anti-fibrotic effect has been attributed to the presence of adipose-derived stromal cells (ADSC). In the proposed study, we aim to investigate the effect of fat grafting in 3D organotypic skin cultures mimicking an HTS-like environment. To this end, organotypic skin cultures were embedded with normal skin fibroblasts (NF) or HTS-derived fibroblasts with or without incorporation of human adipose subcutaneous tissue (ADT) and one part was thermally wounded to examine their effect on epithelialization. The developed skin cultures were analysed on morphology and protein level. Analysis revealed that ADT-containing organotypic skin cultures comprise an improved epidermal homeostasis, and a fully formed basement membrane, similar to native human skin (NHS). Furthermore, the addition of ADT significantly reduced myofibroblast presence, which indicates its anti-fibrotic effect. Finally, re-epithelialization measurements showed that ADT reduced re-epithelialization in skin cultures embedded with NFs, whereas HTS-fibroblast-embedded skin cultures showed complete wound closure. In conclusion, we succeeded in developing a 3D organotypic HTS-skin model incorporated with subcutaneous tissue that allows further investigation on the molecular mechanism of fat grafting.

Pediatric Keloids and Review of the Efficacy of Current Treatment Modalities

BACKGROUND

Keloids and hypertrophic scars are the result of excessive fibroblast proliferation and collagen deposition in the wound healing process, leaving patients with irritating and cosmetically displeasing lesions. Despite there being numerous modalities for treatment, keloids are notoriously recalcitrant to therapy and recurrence rates are high.

OBJECTIVE

Because many keloids begin to develop during childhood and adolescence, it is important to better understand which treatment options may be best suited toward the pediatric population specifically.

METHODS

We reviewed 13 studies that focus specifically on effectiveness of treatment options for keloids and hypertrophic scars in the pediatric population. These studies cover 545 keloids in 482 patients, all aged 18 and younger.

RESULTS

Many treatment modalities were used, with multimodal treatment being the most common (76%). There were 92 instances of recurrence, with a total recurrence rate of 16.9%.

CONCLUSION

Data from the combined studies suggest that keloid development is less common before adolescence and that higher rates of recurrence are observed among patients who have received monotherapy compared with those who received multimodal treatments. More well-designed studies with standardized ways of assessing outcomes are needed to expand our understanding on how to optimally treat keloids in the pediatric population.

Prevalence and risk factors of acne scars in patients with acne vulgaris

BACKGROUND

Acne scar is a persistent complication of acne vulgaris. However, the prevalence and risk factors are still unclear. This study aimed to assess the global prevalence and risk factors of acne scars in patients with acne.

MATERIALS AND METHODS

A systematic search of published studies in three databases was performed and the meta-analyses were conducted.

RESULTS

Finally, we included 37 studies involving 24 649 acne patients. And, the pooled prevalence of acne scars in these patients was 47% (95% confidence interval [CI]: 38-56%). Besides, the differences in prevalence were observed based on the subgroup analysis for age, gender, acne severity, source of patients, and so on. Subsequently, we quantified the relationship of three risk factors with acne scars: male gender (odds ratio [OR]: 1.58, 95% CI: 1.19-2.09), positive family history of acne (OR: 2.73, 95% CI: 1.26-5.91), and acne severity (OR for moderate acne: 2.34, 95% CI: 1.54-3.57; OR for severe acne: 5.51, 95% CI: 2.45-12.41).

CONCLUSION

Herein, we found that 47% of acne patients suffered from acne scars and identified three risk factors: male gender, positive family history of acne, and acne severity. In order to reduce acne scarring, attention and effective therapy early in the course of acne is important.

Immune cells and associated molecular markers in dermal fibrosis with focus on raised cutaneous scars

Raised dermal scars including hypertrophic, and keloid scars as well as scalp-associated fibrosing Folliculitis Keloidalis Nuchae (FKN) are a group of fibrotic raised dermal lesions that mostly occur following cutaneous injury. They are characterized by increased extracellular matrix (ECM) deposition, primarily excessive collagen type 1 production by hyperproliferative fibroblasts. The extent of ECM deposition is thought to be proportional to the severity of local skin inflammation leading to excessive fibrosis of the dermis. Due to a lack of suitable study models, therapy for raised dermal scars remains ill-defined. Immune cells and their associated markers have been strongly associated with dermal fibrosis. Therefore, modulation of the immune system and use of anti-inflammatory cytokines are of potential interest in the management of dermal fibrosis. In this review, we will discuss the importance of immune factors in the pathogenesis of raised dermal scarring. The aim here is to provide an up-to-date comprehensive review of the literature, from PubMed, Scopus, and other relevant search engines in order to describe the known immunological factors associated with raised dermal scarring. The importance of immune cells including mast cells, macrophages, lymphocytes, and relevant molecules such as cytokines, chemokines, and growth factors, antibodies, transcription factors, and other immune-associated molecules as well as tissue lymphoid aggregates identified within raised dermal scars will be presented. A growing body of evidence points to a shift from proinflammatory Th1 response to regulatory/anti-inflammatory Th2 response being associated with the development of fibrogenesis in raised dermal scarring. In summary, a better understanding of immune cells and associated molecular markers in dermal fibrosis will likely enable future development of potential immune-modulated therapeutic, diagnostic, and theranostic targets in raised dermal scarring.

Current advances in the selection of adjuvant radiotherapy regimens for keloid

Keloid is a common benign skin tumor in the outpatient department, and patients are often accompanied by itching and pain. Since the pathogenesis is unknown, the effect of single method treatment is unsatisfactory, and therefore the recurrence rate is high. Therefore, comprehensive treatment is mostly used in clinical treatment. Adjuvant radiotherapy is currently one of the most effective treatments for keloid. After long-term clinical practice, brachytherapy and electron beam radiotherapy has increasingly become the gold standard of treatment, because brachytherapy provides more focused radiation treatment to focal tissue to significantly reduce recurrence rate, and better preserve normal tissue. With the development of new radiotherapy techniques, more options for the treatment of keloid. Currently, adjuvant radiotherapy has been widely recognized, but there is no consensus on the optimal protocol for adjuvant radiotherapy for keloids. This review provides a review of published treatment options and new radiotherapy techniques for adjuvant radiotherapy of keloids and gives a comprehensive evaluation for clinical treatment.

Radiation-induced FAP + fibroblasts are involved in keloid recurrence after radiotherapy

Background: Keloid scars (KSs), which are composed of abnormal hyperplastic scar tissue, form during skin wound healing due to excessive fibroblast activation and collagen secretion. Although surgical resection and radiation therapy are used to prevent recurrence, KS recurrence rates range from 15 to 23%, and the underlying mechanism is unclear.

Methods: To elucidate the mechanism of keloid recurrence, we established a PDX model and the grafts remained for over 20 weeks after transplantation on the bilateral backs of the NCG mice.

Results: RNA-seq revealed that KS tissue gene expression was highly consistent before and after transplantation. Then, one side of the KS graft was irradiated with electron beam therapy (10 Gy), significant increases in vimentin and fibroblast activation protein alpha (FAP) expression were observed after irradiation and were accompanied by severe microvascular destruction. Surprisingly, 4 weeks after irradiation, significantly increased recurrence was observed with increased FAP + tissue and cell cycle regulator expression, resulting in a remarkable altered graft volume. Moreover, irradiation-induced FAP upregulation markedly facilitated radiation resistance and increased cell cycle progression, decreased senescence, and increased energy production.

Conclusion: Our findings revealed that irradiation causes increased abundance of FAP + cells, which was associated with cell proliferation and delayed cellular senescence, accompanied by ATP production.

Platelet-rich plasma in the treatment of scars, to suggest or not to suggest? A systematic review and meta-analysis

Despite the rising trend for applying platelet-rich plasma (PRP) in the management of various types of scars, there is no convincing evidence supporting its use. This motivated us to review the randomized clinical trials that examine the effectiveness and safety of PRP, alone or in combination with other methods, for the management of atrophic or hypertrophic/keloidal scars. The Web of Science, Scopus, Google Scholar, and Cochrane Library databases were systematically searched until September 1^st , 2020. Thirteen clinical trials were enrolled in the meta-analysis, and 10 more were reviewed for their results. The random effect meta-analysis method was used to assess the effect size of each outcome for each treatment type, and I² was used to calculate the statistical heterogeneity between the studies. Patients treated with PRP experienced an overall response rate of 23%, comparable to the results seen with laser or micro-needling (22% and 23%, respectively) When used alone, moderate improvement was the most frequently observed degree of response with PRP (36%) whereas, when added to laser or micro-needling, most patients experienced marked (33%, 43%, respectively) or excellent (32% and 23%, respectively) results. Concerning the hypertrophic/keloid scars, the only study meeting the required criteria reported a better improvement and fewer adverse effects when PRP was added to the intralesional corticosteroids. Platelet-rich plasma appears to be a safe and effective treatment for various types of atrophic scars. In addition, when added to ablative lasers or micro-needling, it seems to considerably add to the efficacy of treatment and reduce the side effects.

Scar-centered dilation in the treatment of large keloids

BACKGROUND

Hypertrophic scars and keloid treatment is a major problem in plastic surgery. While small keloids can be treated with resection followed by radiotherapy, large keloids require treatment with a tissue expander. Conventional methods increase the need for auxiliary incisions, causing new scar hyperplasia.

AIM

To introduce a new method for the treatment of keloids with an expander.

METHODS

Between 2018 and 2021, we performed surgeries to treat large keloids in nine patients with a two-stage approach. In the first stage, an intrascar incision was made in the keloid, and a customized expander was implanted under the keloid and the surrounding normal skin. A period of 3-6 mo was allowed for skin expansion. In the second stage, after the initial incision healed, a follow-up surgery was performed to remove the expander, resect the keloid, and repair the expanded skin flap. To accomplish this, an incision was made along the scar boundary to avoid making a new surgical incision and creating new scars. Superficial radiotherapy was then performed postoperatively.

RESULTS

Two patients had anterior chest keloids. After treatment, the anterior chest incision was broken repeatedly and then sutured again after debridement. It healed smoothly without scar hyperplasia. Keloids were successfully removed in 7 patients without recurrence.

CONCLUSION

This method was performed through a keloid incision and with a custom expander embedded. After full expansion, the keloid was directly resected using a linear suture, which avoids new surgical incisions and scars and can successfully remove large-area keloids. The treatment is effective, providing new insights and strategies for the treatment of similar large-area keloid and hypertrophic scar cases in the future.

The emerging therapeutic targets for scar management: genetic and epigenetic landscapes

Background

Wound healing is a complex process including hemostasis, inflammation, proliferation, and remodeling during which an orchestrated array of biological and molecular events occurs to promote skin regeneration. Abnormalities in each step of the wound healing process lead to reparative rather than regenerative responses, thereby driving the formation of cutaneous scar. Patients suffering from scars represent serious health problems such as contractures, functional and esthetic concerns as well as painful, thick, and itchy complications, which generally decrease the quality of life and impose high medical costs. Therefore, therapies reducing cutaneous scarring are necessary to improve patients' rehabilitation.

Summary

Current approaches to remove scars, including surgical and nonsurgical methods, are not efficient enough, which is in principle due to our limited knowledge about underlying mechanisms of pathological as well as the physiological wound healing process. Thus, therapeutic interventions focused on basic science including genetic and epigenetic knowledge are recently taken into consideration as promising approaches for scar management since they have the potential to provide targeted therapies and improve the conventional treatments as well as present opportunities for combination therapy. In this review, we highlight the recent advances in skin regenerative medicine through genetic and epigenetic approaches to achieve novel insights for the development of safe, efficient, and reproducible therapies and discuss promising approaches for scar management.

Key Message

Genetic and epigenetic regulatory switches are promising targets for scar management, provided the associated challenges are to be addressed.

Krox20 Expression in Abnormal Scars: An Immunohistochemical Study

BACKGROUND

Scars are the end outcome of healing. They are grouped into several types, the common of which are keloid, hypertrophic and atrophic scars. The role of Krox20 in skin and hair physiology and pathology had emerged. Overexpression of Krox20 was sufficient to stimulate collagen gene expression and myofibroblast differentiation and is necessary for transforming growth factor-β (TGF-β) induced profibrotic responses.

OBJECTIVE

to investigate the role of Krox20 in abnormal scar pathogenesis. Hopefully, this insight can set the route for newer therapeutic approaches.

MATERIALS AND METHOD

This study was carried out on 30 cases [10 cases of keloid, 10 cases of atrophic scars and 10 cases with hypertrophic scars (HTS)] and 10 age and gender-matched apparently healthy subjects as a control group. Thirty biopsies were taken from perilesional areas. Evaluation of Krox20 expression was done using standard immunohistochemical technique.

RESULTS

Krox20 was downregulated in epidermis of scar biopsies compared to perilesional and normal skin (P=0.02) while it was overexpressed in fibroblasts in lesional scar biopsies compared to perilesional and normal skin (P<0.001). Keloid cases have significantly higher Krox20 expression in fibroblasts compared with HTS cases (P <0.001). Krox20 had significantly nucleocytoplasmic pattern of staining in scar cases compared with normal skin (P<0.001).

CONCLUSION

Krox20 overexpression may have a role in scar pathogenesis through up-regulation of multiple genes associated with tissue remodeling and wound healing. This may open an avenue for research for new therapies based on Krox20 inhibition.

Molecular Features of Hypertrophic Scars After Thermal Injury: Is There a Biologic Basis for Laser Therapy?

Significance: Hypertrophic scars (HTS) and keloids are common after thermal injuries and other trauma to deep regions of dermis of the skin. These abnormal scars can cause contractures and the thick masses of scar tissue that result in functional and cosmetic impairment. Management of these dermal fibrotic conditions includes a wide range of medical and surgical treatments, which can be time consuming, only partially effective, and often uncomfortable for patients. Recent Advances: The molecular pathophysiology of HTS has become more understood over the past two decades, where thermal injury to the reticular dermis results in an inflammatory response, fibrogenic growth factor release, and the formation of a dermal scar with increased collagen and proteoglycan composition in an abnormal morphology. Lasers are becoming a widely used form of treatment for these types of scars; however, the evidence for the beneficial effects of laser treatments and the understanding of their mechanism of action are still evolving. Critical Issues: Paradoxically, laser delivery of thermal energy to the skin is suggested to improve scar remodeling and wound healing, yet HTS is a well-recognized complication of excessive thermal energy delivered by laser treatments. This review aims to examine the current evidence for the use of lasers for HTS, and to investigate the molecular mechanisms where re-injury of a burn scar from laser treatment could result in overall improvements in scar quality. Future Directions: Improved design of clinical trials for the treatment of scarring in the future will evolve from new methodology and models of HTS in animals and humans.

Dramatic Effect of Botulinum Toxin Type A on Hypertrophic Scar: A Promising Therapeutic Drug and Its Mechanism Through the SP-NK1R Pathway in Cutaneous Neurogenic Inflammation

Background

Hypertrophic scar formation may be related to cutaneous neurogenic inflammation (CNI) through the substance P-neurokinin 1 receptor (SP-NK1R) signaling pathway. As a widely used drug in aesthetic clinical work, botulinum toxin type A (BTX-A) has a therapeutic effect on scars, but the actual mechanism remains unclear. This study aimed to clarify the potential mechanism by which BTX-A inhibits CNI in hypertrophic scars both in vitro and in vivo.

Methods

Tissue samples were obtained from surgical excisions. Immunohistological analysis was used to locate SP in human hypertrophic scars and normal skin. RT-PCR and western blot analysis were used to evaluate the expression of collagens after SP/BTX-A treatment. A rabbit ear scar model was used to explore the in vivo effect of BTX-A on scar treatment.

Results

SP and NK-1R were overexpressed in hypertrophic scars compared to normal skin tissues. Collagen secretion of hypertrophic scar-derived fibroblasts increased with increasing doses of SP. However, BTX-A may downregulate collagen expression through SP-NK1R pathway with or without the presence of SP inducing agent capsaicin. Meanwhile, SP inhibited the expression of NK-1R, and this inhibition was blocked by pretreatment with BTX-A. In vivo, intralesional BTX-A injection can also reduce the volume of scars and inhibit collagen secretion. Capsaicin may cause more severe scar manifestations, while the therapeutic effect of BTX-A remains.

Conclusion

Our research confirms that CNI stimulates fibroblasts during scar formation, while BTX-A can reduce collagen secretion by inhibiting the SP-NK1R signaling pathway, thus identifying a novel therapeutic target for this benign solid skin tumor.

Adjuvant Radiotherapy for Keloids

Radiotherapy is one of the therapeutic methods for keloids, and the irradiation technique has innovated from superficial X-ray to brachytherapy after decades of clinical practice. At present, the application of adjuvant radiotherapy has been widely accepted by clinicians, while the consensus of optimal adjuvant radiotherapy strategies for keloids has not been reached. Factors such as radiation timing, dose, fractions, and lesion locations may be associated with the clinical outcomes of patients with keloids after radiotherapy while a comprehensive review is lacking. Herein, this review summarized the published literature of adjuvant radiotherapy for keloids involving mechanism, timing, dose, fractions, and complications, etc., which may facilitate clinical decision making.Level of Evidence III This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

A Scoping Review of the Methodology Used in Studies of Genetic Influences on the Development of Keloid or Hypertrophic Scarring in Adults and Children After Acute Wounding

Significance: Keloid and hypertrophic scarring are common following acute wounds. However, the variability in scarring outcomes between individuals and in particular, the association between genetic factors and scarring, is not well understood. This scoping review aims to summarize the methodology used in studies of genetic influences on the development of keloid or hypertrophic scarring in adults and children after acute wounding. The objectives were to determine the study designs used, the characteristics of participants included, the tools used to assess scarring and the length of follow-up after wounding.

Recent Advances: The review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Medline, Excerpta Medica Database (EMBASE), Web of Science, Biosciences Information Service (BIOSIS), Prospective Register of Systematic Reviews (PROSPERO), The Human Genetic Epidemiology (HuGE) Navigator (database of genetic association studies), and the genome-wide association study Catalog were searched from January 2008 to April 2020. Cohort studies and case–control studies that examined the association between one or more genetic variations and the development of keloid or hypertrophic scarring were eligible for inclusion. A narrative synthesis that grouped studies by wound type was conducted.

Critical Issues: Nine studies met the inclusion criteria (five in burns, four surgical wounds, and none in other types of acute wounds). Seven assessed hypertrophic scarring, one keloid scarring, and one both scar types. Seven studies used a prospective cohort design. All studies used subjective methods (clinician or patient observation) to assess scarring. There was considerable variation in how scar scales were operationalized.

Future Directions: This review identified a small body of evidence on genetic susceptibility to scarring after acute wounding. Further studies are needed, and in a wide range of populations, including patients with wounds caused by trauma.

Emerging insights into the immunological aspects of keloids

A special kind of scar, keloid, sometimes grows huge, disturbing patients in different ways. We discussed the pathogenesis of keloids and found researches about fibroblasts and collagen disorders, with little emphasis on immunity. Coupled with few effective treatments in keloid at present, we have focused on the immunological mechanisms of keloids with an aim to unravel some new therapeutic approaches in the future. In this review, the immunological processes are separately illustrated by the classification of different immune cells. In addition, we also discuss possible reasons for the repeated recurrence of keloids, the phenomenon of cell talks, and inflammation-related signal pathways involved in the pathogenesis of keloids.

Genetic and Epidemiological Similarities, and Differences Between Postoperative Intraperitoneal Adhesion Development and Other Benign Fibro-proliferative Disorders

Intraperitoneal adhesions complicate over half of abdominal-pelvic surgeries with immediate, short, and long-term sequelae of major healthcare concern. The pathogenesis of adhesion development is similar to the pathogenesis of wound healing in all tissues, which if unchecked result in production of fibrotic conditions. Given the similarities, we explore the published literature to highlight the similarities in the pathogenesis of intra-abdominal adhesion development (IPAD) and other fibrotic diseases such as keloids, endometriosis, uterine fibroids, bronchopulmonary dysplasia, and pulmonary, intraperitoneal, and retroperitoneal fibrosis. Following a literature search using PubMed database for all relevant English language articles up to November 2020, we reviewed relevant articles addressing the genetic and epidemiological similarities and differences in the pathogenesis and pathobiology of fibrotic diseases. We found genetic and epidemiological similarities and differences between the pathobiology of postoperative IPAD and other diseases that involve altered fibroblast-derived cells. We also found several genes and single nucleotide polymorphisms that are up- or downregulated and whose products directly or indirectly increase the propensity for postoperative adhesion development and other fibrotic diseases. An understanding of the similarities in pathophysiology of adhesion development and other fibrotic diseases contributes to a greater understanding of IPAD and these disease processes. At a very fundamental level, blocking changes in the expression or function of genes necessary for the transformation of normal to altered fibroblasts may curtail adhesion formation and other fibrotic disease since this is a prerequisite for their development. Similarly, applying measures to induce apoptosis of altered fibroblast may do the same; however, apoptosis should be at a desired level to simultaneously ameliorate development of fibrotic diseases while allowing for normal healing. Scientists may use such information to develop pharmacologic interventions for those most at risk for developing these fibrotic conditions.

Inhibition of CUB and sushi multiple domains 1 (CSMD1) expression by miRNA-190a-3p enhances hypertrophic scar-derived fibroblast migration in vitro

Background

Hypertrophic scar (HTS) is a fibroproliferative skin disorder characterized by excessive cell proliferation, migration, and extracellular matrix (ECM) deposition. The CUB and Sushi multiple domains 1 (CSMD1) has previously been identified as the key regulatory gene of hypertrophic scar by a large sample GWAS study. However, further research has not yet been conducted to verify this finding in other HTS patients and to determine the underlying mechanism.

Results

In this study, we verified that CSMD1 was downregulated in both HTS tissue and HTS-derived fibroblasts. The knockdown of CSMD1 resulted in enhanced migration and fibronectin1 (FN1) secretion in fibroblasts in vitro. In addition, the upstream and downstream regulatory mechanisms of CSMD1 were also investigated through microRNA (miRNA) databases screening and RNA-sequencing (RNA-seq) respectively. The screening of four common microRNA (miRNA) databases suggested that miR-190a-3p binds to the CSMD1 and may regulate its expression. We confirmed that miR-190a-3p directly targeted the CSMD1–3′-UTR using luciferase reporter assays. Furthermore, the overexpression of miR-190a-3p showed promotion of migratory activity and FN1 secretion in fibroblasts, resembling the effect of CSMD1 knockdown; whereas the knockdown of miR-190a-3p exerted the opposite effect. Finally, transcriptomic analysis showed activation of Janus kinase-signal transducer and activator of transcription (JAK/STAT) signaling pathway in the CSMD1 knockdown fibroblasts.

Conclusions

This study has validated the conclusions of the previous GWAS study conducted in Chinese population. In vitro experiments have provided further evidence on the function of CSMD1 in the development of HTS, and have also revealed the underlying upstream and downstream regulating mechanisms. Additionally, the JAK/STAT signaling pathway identified using RNA-seq might provide a potential treatment approach, especially for HTS.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-021-07920-8.

Non-Oncologic Applications of Nanomedicine-Based Phototherapy

Phototherapy is widely applied to various human diseases. Nanomedicine-based phototherapy can be classified into photodynamic therapy (PDT) and photothermal therapy (PTT). Activated photosensitizer kills the target cells by generating radicals or reactive oxygen species in PDT while generating heat in PTT. Both PDT and PTT have been employed for treating various diseases, from preclinical to randomized controlled clinical trials. However, there are still hurdles to overcome before entering clinical practice. This review provides an overview of nanomedicine-based phototherapy, especially in non-oncologic diseases. Multiple clinical trials were undertaken to prove the therapeutic efficacy of PDT in dermatologic, ophthalmologic, cardiovascular, and dental diseases. Preclinical studies showed the feasibility of PDT in neurologic, gastrointestinal, respiratory, and musculoskeletal diseases. A few clinical studies of PTT were tried in atherosclerosis and dry eye syndrome. Although most studies have shown promising results, there have been limitations in specificity, targeting efficiency, and tissue penetration using phototherapy. Recently, nanomaterials have shown promising results to overcome these limitations. With advanced technology, nanomedicine-based phototherapy holds great potential for broader clinical practice.

Assessing keloid recurrence following surgical excision and radiation

Keloids are a fibroproliferative disorder that can result from a cutaneous injury to the reticular dermis. Recurrence rates as high as 100% have been reported following surgical excision alone. Consequently, a variety of post-surgical techniques have been employed to prevent keloid recurrence, including the use of radiation. Although numerous studies have shown post-excisional X-rays, electron beam, lasers and brachytherapy can reduce the rate of keloid recurrence, numerous inconsistencies, including a wide range of definitions for keloid recurrence, make it difficult to compare study outcomes. The review aims to examine the various means for defining keloid recurrence in clinical trials involving the use of radiation therapy. Searches of the Cochrane Library and PubMed were performed to identify the available information for post-surgical keloid recurrence following radiation therapy. Each identified study was reviewed for patient follow-up and criteria used to define keloid recurrence. The search results included clinical studies with external beam radiation, brachytherapy and superficial radiation therapy. Many studies did not include a definition of keloid recurrence, or defined recurrence only as the return of scar tissue. Other studies defined keloid recurrence based on patient self-assessment questionnaires, symptoms and scar elevation and changes in Kyoto Scar Scale, Japan Scar Workshop Scale and Vancouver Scar Scale scores. The results of this review indicate keloidectomy followed by radiation therapy provide satisfactory recurrence rates; however, clinical studies evaluating these treatments do not describe treatment outcomes or use different definitions of keloid recurrence. Consequently, recurrence rates vary widely, making comparisons across studies difficult. Keloid recurrence should be clearly defined using both objective and subjective measures.

MiR-3613-3p inhibits hypertrophic scar formation by down-regulating arginine and glutamate-rich 1

Hypertrophic scar (HS) is a severe skin disorder characterized by excessive extracellular matrix production and abnormal function of fibroblasts. Recent studies have demonstrated that microRNAs (miRNAs) play critical roles in HS formation. This study aims to investigate the role of miR-3613-3p in the formation of HS. The mRNA and miRNA levels were measured by quantitative RT-PCR analysis. The protein levels were examined by Western blot assay. Cell proliferation was determined by Cell Counting Kit-8 assay. The Caspase-3 and Caspase-9 activities were measured using flow cytometry assay. Dual-luciferase activity reporter assay and mRNA-miRNA pulldown assay were conducted to validate the target of miR-3613-3p. miR-3613-3p was downregulated, while arginine and glutamate-rich 1 (ARGLU1) was upregulated in HS fibroblasts (HSFs) and tissues. Overexpression of miR-3613-3p or knockdown of ARGLU1 markedly inhibited the expression of extracellular matrix (ECM) production-associated proteins and promoted Caspase-3 and Caspase-9 activations in HSFs. ARGLU1 was further identified as a direct target of miR-3613-3p. Restoration of ARGLU1 abrogated the suppressive effect of miR-3613-3p on cell proliferation and ECM protein expression of HSFs. Our results demonstrated that miR-3613-3p inhibited HS formation via targeting ARGLU1, which may provide potential therapeutic targets for the management of HS.

Is There a Genetic Predisposition to Postoperative Adhesion Development?

Adhesions are permanent fibrovascular bands between peritoneal surfaces, which develop following virtually all body cavity surgeries. The susceptibility to develop, and the severity, of adhesions following intra-abdominal surgery varies within and between individuals, suggesting that heritable factors influence adhesion development. In this manuscript, we discuss the pathophysiology of adhesion development from the perspective of genetic susceptibility. We restrict our discussion to genes and single-nucleotide polymorphisms (SNPs) that are specifically involved in, or that cause modification of, the adhesion development process. We performed a literature search using the PubMed database for all relevant English language articles up to March 2020 (n = 186). We identified and carefully reviewed all relevant articles addressing genetic mutations or single-nucleotide polymorphisms (SNPs) that impact the risk for adhesion development. We also reviewed references from these articles for additional information. We found several reported SNPs, genetic mutations, and upregulation of messenger RNAs that directly or indirectly increase the propensity for postoperative adhesion development, namely in genes for transforming growth factor beta, vascular endothelial growth factor, interferon-gamma, matrix metalloproteinase, plasminogen activator inhibitor-1, and the interleukins. An understanding of genetic variants could provide insight into the pathophysiology of adhesion development. The information presented in this review contributes to a greater understanding of adhesion development at the genetic level and may allow modification of these genetic risks, which may subsequently guide management in preventing and treating this challenging complication of abdominal surgery. In particular, the information could help identify patients at greater risk for adhesion development, which would make them candidates for anti-adhesion prophylaxis. Currently, agents to reduce postoperative adhesion development exist, and in the future, development of agents, which specifically target individual genetic profile, would be more specific in preventing intraperitoneal adhesion development.

Abdominal and perineal scar endometriosis: Retrospective study on 40 cases

OBJECTIVE(S)

Abdominal and perineal scar endometriosis usually develop in association with a prior surgical scar. The purpose of the study was to detect and review patients' characteristics of these women over a long period.

STUDY DESIGN

We retrospectively review the clinical records of 860 women with endometriosis between 1989 and 2019. Data were collected and analyzed from medical and pathological reports of 40 patients with abdominal and perineal scar endometriosis.

RESULTS

26 patients (3,0 %) were detected in the abdominal wall endometriosis group (AWE) (mean age 36,5 ± 3,4 years) and 14(1,6 %) cases in the perineal endometriosis (PE) group (32,5 ± 2,4 years), respectively. We observed that 92,3 % of women with AWE had undergone at least 1 cesarean section. Moreover, the majority of patients presented with abdominal pain (77, 0 %) and sensation of a mass (96,2 %). 15,4 % of cases had concurrent pelvic endometriosis and the recurrent rate of the disease was 15,4 %. All cases with perineal scar endometriosis were multiparous and delivered vaginally with episiotomy. 92,8 % of patients presented with cyclical pain and swelling. 3 cases suffered from perineal endometriosis combined with pelvic endometriosis. There was a recurrence of perineal endometriosis in 2 women (14,2 %). Surgical excision was the standard treatment of this condition and tissue biopsy confirmed the diagnosis.

CONCLUSIONS

Abdominal wall and perineal scar endometriosis are rare, multifactorial entities which are associated mainly with cesarean section and vaginal episiotomy. Clinicians should be aware of these conditions among all women of reproductive age presenting with cyclic or non-cyclic pain and swelling at the incision sites.

Radiation Therapy for Benign Disease: Keloids, Macular Degeneration, Orbital Pseudotumor, Pterygium, Peyronie Disease, Trigeminal Neuralgia

Although the use of ionizing radiation on malignant conditions has been well established, its application on benign conditions has not been fully accepted and has been inadequately recognized by health care providers outside of radiation therapy. Most frequently, radiation therapy in these benign conditions is used along with other treatment modalities, such as surgery, when the condition causes significant disability or could even lead to death. Radiation therapy can be helpful for inflammatory/proliferative disorders. This article discusses the present use of radiation therapy for some of the most common benign conditions.

Iatrogenic subglottic tracheal stenosis after tracheostomy and endotracheal intubation: A cohort observational study of more severity in keloid phenotype

Background

Tracheostomy and endotracheal intubation can result in subglottic tracheal stenosis, and predisposition to keloid scar formation can increase stenosis risk after tracheal injury. This study aims to compare the incidence and severity of subglottic tracheal stenosis in keloid and non‐keloid patients following iatrogenic tracheal injury, in particular tracheostomy.

Methods

From 2012 to 2017, 218 573 patients were intubated for surgery; 2276 patients received tracheostomy in People’s Hospital of Zhengzhou University, China. Among these patients, 133 patients, who developed tracheal stenosis after intubation and/or tracheostomy, were divided into keloid or non‐keloid groups; their Myer and Cotton grading of tracheal stenosis, time‐to‐onset of airway stenosis, and treatment outcome were assessed and compared.

Results

The percentages of high grade (Myer and Cotton grading III/IV) tracheal stenosis were higher among keloid patients than non‐keloid patients (intubation: 83.3% vs 25.7%; tracheostomy: 77.7% vs 33.3%). Time‐to‐onset of airway stenosis following intubation (tracheostomy) was 27 ± 5 (38 ± 13) and 41 ± 7 (82 ± 14) days for keloid and non‐keloid patients, respectively (P < 0.01). The incidence of tracheal stenosis is higher in keloid than non‐keloid subjects (19.4% vs 1.82%, P < 0.001). Keloid patients also required more frequent treatment (P < 0.01) of longer duration, yet cure rate was significantly lower (P < 0.01).

Conclusions

Our study suggests that tracheostomized patients with keloid phenotype are more susceptibility to develop iatrogenic tracheal stenosis of greater severity and with poorer treatment outcome. Greater cautions may be required when performing tracheostomy in keloid subjects. More substantive analysis is warranted to establish keloid phenotype as a risk factor for tracheal stenosis.

Genetic influence on scar height and pliability after burn injury in individuals of European ancestry: A prospective cohort study

After similar extent of injury there is considerable variability in scarring between individuals, in part due to genetic factors. This study aimed to identify genetic variants associated with scar height and pliability after burn injury. An exome-wide array association study and gene pathway analysis were performed on a prospective cohort of 665 patients treated for burn injury. Outcomes were scar height (SH) and scar pliability (SP) sub-scores of the modified Vancouver Scar Scale (mVSS). DNA was genotyped using the Infinium^® HumanCoreExome-24 BeadChip. Associations between genetic variants (single nucleotide polymorphisms) and SH and SP were estimated using an additive genetic model adjusting for age, sex, number of surgical procedures and % total body surface area of burn in subjects of European ancestry. No individual genetic variants achieved the cut-off threshold of significance. Gene regions were analysed for spatially correlated single nucleotide polymorphisms and significant regions identified using comb-p software. This gene list was subject to gene pathway analysis to find which biological process terms were over-represented. Using this approach biological processes related to the nervous system and cell adhesion were the predominant gene pathways associated with both SH and SP. This study suggests genes associated with innervation may be important in scar fibrosis. Further studies using similar and larger datasets will be essential to validate these findings.

Enhanced wound healing in diabetic rats by nanofibrous scaffolds mimicking the basketweave pattern of collagen fibrils in native skin

Nanofibrous scaffolds that offer proper microenvironmental cues to promote the healing process are highly desirable for patients with chronic wounds. Although studies have shown that fiber organization regulates cell behaviors in vitro, little is known about its effects on the wound healing process in vivo. Most of the nanofibrous scaffolds currently used in skin repair are randomly oriented. Herein, inspired by the basketweave-like pattern of collagen fibrils in native skin, we fabricated biomimetic nanofibrous scaffolds with crossed fiber organization via electrospinning. The regulation of crossed nanofibrous scaffolds on fibroblasts was compared with that of aligned and random nanofibrous scaffolds. Unexpectedly, crossed nanofibrous scaffolds induced different cellular responses in fibroblasts, including differences in cellular morphology, migration and wound healing related gene expression, in comparison to either aligned or random nanofibrous scaffolds. More importantly, the regulation of nanofibrous scaffolds with different fiber organizations on wound repair was systematically investigated in diabetic rats. While the healing processes were enhanced by all nanofibrous scaffolds, wounds treated with crossed nanofibrous scaffolds achieved the best healing outcome, which was evidenced by the resolution of inflammation, the accelerated migration of fibroblasts and keratinocytes, and the promotion of angiogenesis. These findings helped reveal the role of fiber organization in regulating the wound healing process in vivo and suggest the potential utility of biomimetic crossed nanofibrous scaffolds for the repair of chronic wounds.

An intra-individual surgical wound comparison shows that octenidine-based hydrogel wound dressing ameliorates scar appearance following abdominoplasty

Hypertrophic scar formation because of surgical procedures is associated with higher levels of pain, a lower quality of life, and poor cosmetic outcome and requires more resources in follow-up management. An octenidine-based hydrogel has been shown to modulate immunological function in an in vitro wound model, suggesting an improved scar formation. In this prospective, randomised, observer-blinded, and intra-patient-controlled study, 45 patients who underwent abdominoplasty or mastectomy with transverse rectus abdominis muscle (TRAM) flap reconstruction were given both a standard postoperative wound dressing on one wound side and an octenidine-based hydrogel with transparent film dressing, covered with standard postoperative dressing on the other side. Four instances of hypertrophia were reported in the gel side versus 12 in the standard dressing side. Visual Analogue Scale (VAS) pain scores taken during postoperative dressing changes showed reduced scores on the gel side at all time points. Vancouver Scar Scale (VSS) scores showed improvement in the gel side at 3, 6, and 12 months postoperatively. Skin distensibility measured using a cutometer showed significantly improved measures in gel-treated wounds, similar to measures of healthy skin. Trans-epidermal water loss (TEWL), measured using a tewameter, showed improved values on the gel side soon after surgery, with both the control and the gel side normalising after approximately 6 months. The octenidine-based wound dressing demonstrates improved wound healing associated with a lower incidence of hypertrophic scar formation.

Profibrogenic effect of high-mobility group box protein-1 in human dermal fibroblasts and its excess in keloid tissues

High-mobility group box 1 (HMGB1) protein acts as a DNA chaperone for nuclear homeostasis. It translocates into the cytosol and is secreted into extracellular spaces, triggering proinflammatory cytokines and acting as a mediator in fibrosis. We determined whether HMGB1 plays a role in normal dermal fibrosis and keloid, and is involved with transforming growth factor β. We investigated the translocation and active release of HMGB1 from normal dermal fibroblasts under lipopolysaccharide stimuli, and the redistribution of nuclear HMGB1 into the cytoplasm of keloid fibroblasts. HMGB1 and its effector toll-like receptors and receptors for advanced glycation end product proteins are actively expressed in keloid tissues. Exogenous HMGB1 can induce the proliferation of human dermal fibroblasts, and could act as a profibrogenic molecule to produce collagen, decrease MMP-1, and increase TIMP-1 mRNA expression. Moreover, administration of HMGB1 increased the expression level of TGF-β1 and internal signaling molecules, such as Smad 2 and 3, phosphorylated Smad 2/3 complex, Erk 1/2, Akt, and NF-κB. Collectively, we demonstrate that HMGB1 treatment increases the expression level of collagen types I and III, elastin, and fibronectin in dermal spheroid cultures, thus making HMGB1 a promising therapeutic target for treatment of profibrogenic diseases.

Comparison of Pterygium Recurrence Rates Among Different Races and Ethnicities After Primary Pterygium Excision by Surgeons in Training

PURPOSE

To evaluate the impact of race and ethnicity, surgical technique, and level of surgeon training on recurrence rates after primary pterygium excision.

METHODS

A retrospective review of patients who underwent primary pterygium excision at our academic institution was performed. The surgical technique-conjunctival autografting (CAG) or amniotic membrane grafting (AMG)-was chosen at the attending surgeon's discretion, and all surgeries were performed by surgeons in training. The primary outcome measure was pterygium recurrence, defined as regrowth of fibrovascular tissue onto a clear cornea in the region of previous pterygium removal.

RESULTS

There was a significant difference in age at presentation between white (64.3 ± 11.4), Hispanic (50.0 ± 13.5), black (64.8 ± 14.5), and Asian (59.3 ± 9.2) patients (P < 0.001). Average time to recurrence was 4.4 ± 3.0 months and was similar between races (P = 0.98). There was a significant difference in recurrence rates between the white (13%), Hispanic (28%), black (33%), and Asian (0%) patients (P = 0.049). Over 12 months, a significant difference in cumulative proportion with recurrence after AMG versus CAG was observed in Hispanic (75% vs. 30%; P = 0.002) and black (100% vs. 42%; P = 0.001) patients. Sex, method of graft fixation (glue, suture, or both), and level of surgeon training showed no difference in pterygium recurrence (P > 0.05).

CONCLUSIONS

Hispanic and black patients are more likely to experience pterygium recurrence after AMG than CAG. White patients are less likely than Hispanic or black patients to experience recurrence regardless of the surgical technique. To reduce the likelihood of recurrence, surgeons may consider race and ethnicity when selecting their operative technique.

Radiation Therapy in Keloids Treatment: History, Strategy, Effectiveness, and Complication

Objective:

Radiation therapy combined with surgical excision was considered as one of the most effective treatment plans for keloid lesions. However, there was no unanimity found over present literatures regarding the issue on optimized treatment strategy for keloids. We here provide a comprehensive review over this issue and emphasize on the influencing factors.

Data Sources:

The data analyzed in this review were searched from articles included in PubMed and EMBASE databases.

Study Selection:

The original articles and critical reviews discussing the application of radiation therapy in keloids treatment were selected for this review.

Results:

The application of radiation therapy has transitioned from simple superficial X-ray irradiation to brachytherapy. Furthermore, several factors including radiation type, dose, fraction, interval, and complications were reviewed, and the results revealed that these factors were significant toward clinical outcome at various levels.

Conclusions:

Both past and present evidence support the idea that combination therapy of radiation and surgical therapy is safe and feasible. However, the optimization of treatment strategy was based on different radiation types and should take dose, fractions, interval, and complications into consideration, which will then decrease the rate of recurrence and increase the level of satisfaction.

Abdominal scar characteristics as a predictor of cervical stenosis after abdominal radical trachelectomy

To investigate whether abdominal scar characteristics could predict the occurrence of cervical stenosis after abdominal radical trachelectomy (ART), we conducted a retrospective study and investigated the relationship between abdominal scar characteristics and the occurrence of cervical stenosis in patients one year after undergoing ART. The abdominal scars were evaluated using the Vancouver Scar Scale (VSS). Seventy-two participants were enrolled in the study, including 15 (20.8%) women with cervical stenosis, and 57 (79.2%) without stenosis. Results showed that the mean abdominal scar score assessed by VSS was higher in patients with cervical stenosis (7, range: 1-10) compared to those without stenosis (4, range: 0-9) (P = 0.001). Incidence rates of cervical stenosis increased with the VSS score. For women with VSS scores of 0 to 4, 5, 6, 7, 8, 9 and 10, respectively, the occurrences of cervical stenosis were 6.1%, 16.7%, 16.7%, 27.3%, 37.5%, 50% and 100%. The cutoff point of VSS score was 7 according to the receiver operating characteristic (ROC) curve. Fourteen of the 15 stenosis happened either in patients without anti-stenosis tools (Foley catheters or tailed intrauterine devices) placed during the surgery or after the devices were removed. Our results demonstrated that VSS is an effective approach to assess the presence of cervical stenosis after ART. Women who have an abdominal scar with a VSS score > 7 have a high risk of developing isthmic stenosis without anti-stenosis tools in place.

Pathophysiologic Mechanisms and Current Treatments for Cutaneous Sequelae of Burn Wounds

Burn injuries are a pervasive clinical problem. Extensive thermal trauma can be life-threatening or result in long-lasting complications, generating a significant impact on quality of life for patients as well as a cost burden to the healthcare system. The importance of addressing global or systemic issues such as resuscitation and management of inhalation injuries is not disputed but is beyond the scope of this review, which focuses on cutaneous pathophysiologic mechanisms for current treatments, both in the acute and long-term settings. Pathophysiological mechanisms of burn progression and wound healing are mediated by highly complex cascades of cellular and biochemical events, which become dysregulated in slow-healing wounds such as burns. Burns can result in fibroproliferative scarring, skin contractures, or chronic wounds that take weeks or months to heal. Burn injuries are highly individualized owing to wound-specific differences such as burn depth and surface area, in addition to patient-specific factors including genetics, immune competency, and age. Other extrinsic complications such as microbial infection can complicate wound healing, resulting in prolonged inflammation and delayed re-epithelialization. Although mortality is decreasing with advancements in burn care, morbidity from postburn deformities continues to be a challenge. Optimizing specialized acute care and late burn outcome intervention on a patient-by-patient basis is critical for successful management of burn wounds and the associated pathological scar outcome. Understanding the fundamentals of integument physiology and the cellular processes involved in wound healing is essential for designing effective treatment strategies for burn wound care as well as development of future therapies. Published 2018. Compr Physiol 8:371-405, 2018.

Scar Prevention and Enhanced Wound Healing Induced by Polydeoxyribonucleotide in a Rat Incisional Wound-Healing Model

High-mobility group box protein-1 (HMGB-1) plays a central role in the inflammatory network, and uncontrolled chronic inflammation can lead to excessive scarring. The aim of this study was to evaluate the anti-inflammatory effects of polydeoxyribonucleotide (PDRN) on scar formation. Sprague-Dawley rats (n = 30) underwent dorsal excision of the skin, followed by skin repair. PDRN (8 mg/kg) was administered via intraperitoneal injection for three (PDRN-3 group, n = 8) or seven (PDRN-7 group, n = 8) days, and HMGB-1 was administered via intradermal injection in addition to PDRN treatment for three days (PDRN-3+HMGB-1 group; n = 6). The scar-reducing effects of PDRN were evaluated in the internal scar area and by inflammatory cell counts using histology and immunohistochemistry. Western blot, immunohistochemistry and immunofluorescence assays were performed to observe changes in type I and type III collagen and the expression of HMGB-1 and CD45. Treatment with PDRN significantly reduced the scar area, inflammatory cell infiltration and the number of CD45-positive cells. In addition, the increased expression of HMGB-1 observed in the sham group was significantly reduced after treatment with PDRN. Rats administered HMGB-1 in addition to PDRN exhibited scar areas with inflammatory cell infiltration similar to the sham group, and the collagen synthesis effects of PDRN were reversed. In summary, PDRN exerts anti-inflammatory and collagen synthesis effects via HMGB-1 suppression, preventing scar formation. Thus, we believe that the anti-inflammatory and collagen synthesis effects of PDRN resulted in faster wound healing and decreased scar formation.

Aesthetics in Thyroid Surgery: The Patient Perspective

Objectives

To define characteristics that influence patient perceptions of thyroidectomy scar cosmesis.

Study Design

Prospective cohort study.

Setting

Tertiary endocrine surgery practice in an academic medical center.

Subjects and Methods

Institutional review board–approved trial in which 136 subjects were recruited from a population of patients being seen for either thyroid or sinus surgery and evaluated standardized photographs, superimposed with computer-generated thyroidectomy scars of varying lengths (2, 4, and 6 cm) and widths (1 and 2 mm), and graded their perception of the scars using the observer scar assessment scale (OSAS) domains of the patient and observer scar assessment scale.

Results

There were 69 subjects in the thyroid group and 67 in the nonthyroid group. Controlling for width, longer scars were perceived as worse than shorter scars; controlling for length, thicker scars were perceived as worse than thinner scars ( P < .01). Beyond 2 cm, thick scars were judged to be worse than thin scars, even when they were shorter. There was no difference in the mean overall OSAS scores between surgery, sex, or age groups. Nonwhites tended to judge scars as being worse than whites did ( P < .01).

Conclusion

As expected, patients of all demographics prefer shorter scars compared with longer scars and thinner scars over thick scars. Ethnic differences in scar perception were identified and deserve additional study. Surgeons should endeavor to perform thyroid surgery through the smallest incision that allows the operation to be performed safely to minimize the cosmetic impact of the operation.

Columellar Incision Scars in Asian Patients Undergoing Open Rhinoplasty

IMPORTANCE

An open approach has been adopted for rhinoplasty because of its wide and undistorted exposure. The formation of a columellar incision scar is the main drawback of this approach.

OBJECTIVE

To evaluate the incidence and evolution of and risk factors for columellar incision scars in an Asian population.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective case series of 529 patients who underwent open rhinoplasty was performed in a tertiary care referral center in South Korea from January 1, 2011, to May 31, 2014. Problematic transcolumellar incision scars were categorized into wide and depressed, notching, and hyperpigmented wound types. Follow-up was complete on January 28, 2015, and data were assessed from July 1, 2014, to May 29, 2015.

MAIN OUTCOMES AND MEASURES

The incidence of each problematic scar and the time course of erythema evolution were evaluated. Factors affecting the formation of a problematic scar were also evaluated.

RESULTS

Of 529 patients (176 female and 353 male patients; mean age, 31 [range, 5-70] years), 234 patients with at least 6 months of follow-up underwent evaluation for a problematic scar. Fourteen of the 234 patients (6.0%) had problematic incision scarring (wide and depressed wound, 4 [1.7%]; notching wound, 3 [1.3%]; hyperpigmentation, 4 [1.7%]; marginal incision hypertrophic scar, 2 [0.8%]; and columellar skin necrosis, 1 [0.4%]). Of the 243 patients with regular follow-up who underwent evaluation for erythema evolution, erythematous wounds were found in almost all in the immediate postoperative period and had normalized by a mean (SD) of 66.7 (37.4) postoperative days. Use of costal cartilage as tip graft material was associated with a problematic incision scar (2 of 25 patients [8.0%] vs 6 of 180 patients with other graft material [3.3%]; P = .02).

CONCLUSIONS AND RELEVANCE

In this cohort of Asian patients, the incisions used for an open rhinoplasty approach had some problems. However, the low incidence of problematic scars indicates that open rhinoplasty should not be discouraged because of the incision scar.

LEVEL OF EVIDENCE

4.

Immunohistochemical Evaluation of Leptin Expression in Wound Healing: A Clue to Exuberant Scar Formation

Leptin has been recognized as an important factor for promoting normal cutaneous wound healing. The aim of this work was to explore leptin expression in keloid and hypertrophic scars (HS) compared with surgical scars and normal skin. The relationship of this expression with clinicopathologic parameters of studied cases was also evaluated. Using immunohistochemical techniques, leptin was analyzed in skin biopsies of 60 nonobese subjects without metabolic syndrome who presented with keloids (20), HS (20), and surgical scars (20). Twenty normal skin samples, from age-matched, sex-matched, and body mass index-matched subjects, were enrolled as a control group. Leptin showed positive immunoreactivity in epidermis in all cases of surgical scars and keloids and in 75% of HS cases. Dermal expression in fibroblasts, inflammatory cells, and endothelial cells was positive in all cases of surgical scars and keloids and in 70% of HS cases. Leptin was overexpressed in keloids and HS compared with normal skin in epidermis (P<0.001 for both) and dermis (P<0.001 for both) and to surgical scars both in epidermis (P=0.0006, P=0.01, respectively) and dermis (P=0.0001, P=0.001, respectively). Higher leptin H score was significantly associated with older age (P=0.02) and positive family history (P=0.002) in keloid cases and with axial site in keloid and HS cases (P=0.001, P=0.02, respectively). Significant positive correlation was noted between epidermal and dermal leptin H scores in keloids (r=+0.37, P=0.04) and HS (r=+0.39, P=0.02). This may be due to epithelial-mesenchymal interactions in scar pathogenesis. In conclusion, in situ leptin overexpression may increase the possibility of keloid and HS occurrence through altered cytokine production and prolonged healing phases with excessive deposition and delayed collagen degradation. This may open an avenue for research for new therapeutic modalities based on its inhibition.

Identification of genes differentially expressed in menstrual breakdown and repair

STUDY QUESTION

Does the changing molecular profile of the endometrium during menstruation correlate with the histological profile of menstruation.

SUMMARY ANSWER

We identified several genes not previously associated with menstruation; on Day 2 of menstruation (early-menstruation), processes related to inflammation are predominantly up-regulated and on Day 4 (late-menstruation), the endometrium is predominantly repairing and regenerating.

WHAT IS KNOWN ALREADY

Menstruation is induced by progesterone withdrawal at the end of the menstrual cycle and involves endometrial tissue breakdown, regeneration and repair. Perturbations in the regulation of menstruation may result in menstrual disorders including abnormal uterine bleeding.

STUDY DESIGN, SIZE DURATION

Endometrial samples were collected by Pipelle biopsy on Days 2 (n = 9), 3 (n = 9) or 4 (n = 6) of menstruation.

PARTICIPANTS/MATERIALS, SETTING, METHODS

RNA was extracted from endometrial biopsies and analysed by genome wide expression Illumina Sentrix Human HT12 arrays. Data were analysed using 'Remove Unwanted Variation-inverse (RUV-inv)'. Ingenuity pathway analysis (IPA) and the Database for Annotation, Visualization and Integrated Discovery (DAVID) v6.7 were used to identify canonical pathways, upstream regulators and functional gene clusters enriched between Days 2, 3 and 4 of menstruation. Selected individual genes were validated by quantitative PCR.

MAIN RESULTS AND THE ROLE OF CHANCE

Overall, 1753 genes were differentially expressed in one or more comparisons. Significant canonical pathways, gene clusters and upstream regulators enriched during menstrual bleeding included those associated with immune cell trafficking, inflammation, cell cycle regulation, extracellular remodelling and the complement and coagulation cascade. We provide the first evidence for a role for glutathione-mediated detoxification (glutathione-S-transferase mu 1 and 2; GSTM1 and GSTM2) during menstruation. The largest number of differentially expressed genes was between Days 2 and 4 of menstruation (n = 1176). We identified several genes not previously associated with menstruation including lipopolysaccharide binding protein, serpin peptidase inhibitor, clade B (ovalbumin), member 3 (SERPINB3) and -4 (SERPINB4), interleukin-17C (IL17C), V-set domain containing T-cell activation inhibitor 1 (VTCN1), proliferating cell nuclear antigen factor (KIAA0101/PAF), trefoil factor 3 (TFF3), laminin alpha 2 (LAMA2) and serine peptidase inhibitor, Kazal type 1 (SPINK1). Genes related to inflammatory processes were up-regulated on Day 2 (early-menstruation), and those associated with endometrial repair and regeneration were up-regulated on Day 4 (late-menstruation).

LIMITATIONS, REASONS FOR CAUTION

Participants presented with a variety of endometrial pathologies related to bleeding status and other menstrual characteristics. These variations may also have influenced the menstrual process.

WIDER IMPLICATIONS OF THE FINDINGS

The temporal molecular profile of menstruation presented in this study identifies a number of genes not previously associated with the menstrual process. Our findings provide valuable insight into the menstrual process and may present novel targets for therapeutic intervention in cases of endometrial dysfunction.

LARGE SCALE DATA

All microarray data have been deposited in the public data repository Gene Expression Omnibus (GSE86003).

STUDY FUNDING AND COMPETING INTERESTS

Funding for this work was provided by a National Health and Medical Research Council of Australia (NHMRC) Project Grant APP1008553 to M.H., P.R. and J.G. M.H. is supported by an NHMRC Practitioner Fellowship. P.P. is supported by a NHMRC Early Career Fellowship. The authors have no conflict of interest to declare.