Keloid and Hypertrophic Scar Formation, Prevention, and Management: Standard Review of Abnormal Scarring in Orthopaedic Surgery

Extracellular Vesicles-in-Hydrogel (EViH) targeting pathophysiology for tissue repair

Regenerative medicine endeavors to restore damaged tissues and organs utilizing biological approaches. Utilizing biomaterials to target and regulate the pathophysiological processes of injured tissues stands as a crucial method in propelling this field forward. The Extracellular Vesicles-in-Hydrogel (EViH) system amalgamates the advantages of extracellular vesicles (EVs) and hydrogels, rendering it a prominent biomaterial in regenerative medicine with substantial potential for clinical translation. This review elucidates the development and benefits of the EViH system in tissue regeneration, emphasizing the interaction and impact of EVs and hydrogels. Furthermore, it succinctly outlines the pathophysiological characteristics of various types of tissue injuries such as wounds, bone and cartilage injuries, cardiovascular diseases, nerve injuries, as well as liver and kidney injuries, underscoring how EViH systems target these processes to address related tissue damage. Lastly, it explores the challenges and prospects in further advancing EViH-based tissue regeneration, aiming to impart a comprehensive understanding of EViH. The objective is to furnish a thorough overview of EViH in enhancing regenerative medicine applications and to inspire researchers to devise innovative tissue engineering materials for regenerative medicine.

Integrating multiomics sequencing analyses uncover the key mechanisms related to oxidative stress, mitochondria, and immune cells in keloid

BACKGROUND

This study aimed to investigate the key molecular mechanisms underlying keloid pathogenesis by integrating oxidative stress, mitochondria, and immune cells.

METHODS

Transcriptome sequencing (mRNA, lncRNA, and circRNA expression data), proteomic sequencing, and small RNA sequencing analyses of lesional and non-lesional skin of patients with keloids and healthy control (normal) skin were conducted. By integrating mRNA and publicly available gene expression data (GSE158395), differentially expressed genes related to oxidative stress and mitochondrial function in keloids were identified. Hub genes were identified using various bioinformatics analyses such as immune infiltration analysis, weighted gene co-expression network analysis, machine learning, and expression validation using proteomics sequencing data. Moreover, a competing endogenous RNA (ceRNA) network of hub genes was constructed by combining miRNA, lncRNA, and circRNA expression data. Five hub genes were identified: MGST1, DHCR24, ALDH3A2, ADH1B, and FKBP5.

RESULTS

These hub genes had a high diagnostic value for keloids, with an AUC value > 0.8 each. In addition, five hub genes were associated with the infiltration of multiple immune cells. The immune cells with the strongest positive and negative correlations with hub genes were M0 and M1 macrophages. A ceRNA network was constructed, and several ceRNAs, such as AC005062.1/miR-134-5p/FKBP5 and BASP1-AS1/miR-503-5p/ADH1B, were identified. These five hub genes may contribute to keloid pathogenesis.

CONCLUSION

These genes and their related ceRNAs may serve as diagnostic biomarkers and therapeutic targets for keloids.

Physical stimuli-responsive polymeric patches for healthcare

Many chronic diseases have become severe public health problems with the development of society. A safe and efficient healthcare method is to utilize physical stimulus-responsive polymer patches, which may respond to physical stimuli, including light, electric current, temperature, magnetic field, mechanical force, and ultrasound. Under certain physical stimuli, these patches have been widely used in therapy for diabetes, cancer, wounds, hair loss, obesity, and heart diseases since they could realize controllable treatment and reduce the risks of side effects. This review sketches the design principles of polymer patches, including composition, properties, and performances. Besides, control methods of using different kinds of physical stimuli were introduced. Then, the fabrication methods and characterization of patches were explored. Furthermore, recent applications of these patches in the biomedical field were demonstrated. Finally, we discussed the challenges and prospects for its clinical translation. We anticipate that physical stimulus-responsive polymer patches will open up new avenues for healthcare by acting as a platform with multiple functions.

Inhibition of Small Extracellular Vesicles by GW4869 Does not Disrupt the Paracrine Regulation of Adipose-Derived Mesenchymal Stem Cells Over Keloid Fibroblasts

BACKGROUND

Keloid, scar caused by atypical wound repair, represents a significant difficulty for specialists in plastic surgery and dermatology. Adipose-derived mesenchymal stem cells (ADSCs) can regulate fibrotic phenotypes of keloid fibroblasts (KFs) in a paracrine fashion, but whether small extracellular vesicles (SEVs) are the key functional carrier in ADSC paracrine regulation of KFs remains unknown. This study aims to explore whether the regulatory effects of conditioned medium (CM) obtained from ADSCs on KFs can be impaired by decreased SEV content in the ADSC-CM.

METHODS

Clinical specimens were utilized to extract keloid fibroblasts (KFs), normal fibroblasts (NFs), and adipose-derived stem cells (ADSCs). Fibroblasts were cultured with CM obtained from ADSCs untreated or treated with the sphingomyelinase inhibitor GW4869. The features of SEVs derived from ADSC-CM were characterized, and fibroblast proliferation, migration, apoptosis, and expression of ECM proteins were analyzed.

RESULTS

The sphingomyelinase inhibitor GW4869 successfully reduced the SEV content in ADSC-CM, and both control ADSC-CM and ADSC-CM with reduced SEV content significantly inhibited KF proliferation, migration, and α-SMA synthesis but not KF apoptosis, whereas only NF proliferation was inhibited by ADSC-CM. The reduced SEV content only affected the inhibition of KF proliferation induced by ADSC-CM.

CONCLUSION

ADSC-CM inhibits various fibrotic phenotypes of KFs, but decreasing the SEV content in ADSC-CM did not significantly alter the antifibrotic effects of ADSC-CM. Thus, SEVs may not be the key mediator of ADSCs paracrine regulation of KFs.

NO LEVEL ASSIGNED

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Activatable Near-Infrared Fluorescence Probe for Hypochlorous Acid Detection in Early Diagnosis of Keloids

Keloids represent pathologic conditions characterized by the presence of hyalinized collagen bundles and chronic inflammatory reactions. Recently, increased ROS production and disrupted apoptosis mechanisms in keloids have been reported, although the detailed mechanisms remain unclear. Herein, we developed a specific fluorescence probe, Pro-NBS, to investigate ClO- levels in keloids. The probe demonstrated high specificity for ClO- over other ROS and exhibited a strong linear detection relationship. Based on its performance, we focused on the TGF-β pathway in the development of keloids. ROS upregulation was observed in keloid-derived fibroblasts. Using ClO- as an intrinsic overexpression marker, our probe effectively distinguished between normal fibroblasts and keloid-derived fibroblasts both in vitro and in vivo. Furthermore, Pro-NBS showed potential for monitoring the progression and evaluating the systematic therapy of abnormal scarring or keloids.

Physical and Psychological Impact of Scar Cosmesis After Cervical Spine Fusion Surgery

INTRODUCTION

Patients' and surgeons' perceptions of cutaneous scarring can vary, causing unpleasant physical and psychological outcomes. This study aims to bridge the current scientific literature gap and understand the impact of patient-perceived scar cosmesis after anterior and posterior cervical spine surgery.

METHODS

Retrospective review of patients ≥18 years old who underwent anterior or posterior cervical spine surgery from 2017 to 2022 at a large, urban academic group. To select patients with adequate time for surgical scar maturation, only patients who were greater than 6 months postsurgery were included. The Scar Questionaire Survey (SCAR-Q) survey, a surgical scar assessment tool, was administered to patients to assess patient perceptions of scar symptomatology, appearance, and psychosocial impact. Scores range from 0 to 100, with 100 as the best outcome. An additional 5-item Likert scale question was administered to assess overall surgical satisfaction.

RESULTS

All 854 respondents who completed the survey were stratified into 2 groups "Unsatisfied vs. Satisfied." Patients who were "unsatisfied" with their surgery had the lowest outcome scores for SCAR-Q appearance, symptom, and psychosocial scores than those who were "Satisfied" (P < 0.001). Females had significantly "higher/more favorable" responses for SCAR-Q Appearance (77.5 vs. 82.8 P < 0.001) and Psychosocial (87.4 vs. 94.3 P < 0.001) scores compared to males. Regression analysis performed for each component score showed that increases in all 3 component scores were significant in patients in the satisfied group.

CONCLUSIONS

Our study demonstrates that cervical spine surgery patients unsatisfied with their surgical outcome have lower scar-related scores, highlighting the impact of cosmetic closure and appearance.

Liposomes Loaded with 5-Fluorouracil Can Improve the Efficacy in Pathological Scars

Introduction

Pathological scars, such as hypertrophic scars and keloids, are characterized by the proliferation of fibroblasts and the deposition of collagen that often cause pruritus, pain, and disfigurement. Due to their high incidence and deformity, pathological scars have resulted in severe physical and psychological trauma for patients. Intralesional injection of 5-fluorouracil (5-Fu) is a recommended option for treating pathological scars. However, the efficacy of 5-Fu injection was limited and unstable due to limited drug penetration and short retention time.

Methods

Liposomes are promising carriers that have advantages, such as high biocompatibility, controlled release property, and enhanced clinical efficacy. Here, we constructed a transdermal 5-Fu-loaded liposome (5-Fu-Lip) to provide a more effective and safer modality to scar treatment.

Results

Compared to 5-Fu, 5-Fu-Lip showed superior ability in inhibiting primary keloid fibroblasts proliferation, migration, and collagen deposition, and also significantly inhibited human umbilical vein endothelial cells (HUVECs) proliferation and microvessel construction. In vivo experiments demonstrated that 5-Fu-Lip can significantly reduce the severity of hypertrophic scars in a rabbit ear wounding model.

Discussion

5-Fu-Lip provides a promising strategy to improve drug efficacy, which has great potential in the treatment of pathological scars.

Role of Emerin in regulating fibroblast differentiation and migration at the substrate of stiffness coupled topology

In hypertrophic scars, the differentiation and migration of fibroblasts are influenced by the extracellular matrix microenvironment, which includes factors such as stiffness, restraint, and tensile force. These mechanical stresses incite alterations in cell behavior, accompanied by cytoskeletal protein reorganization. However, the role of nucleo-skeletal proteins in this context remains underexplored. In this study, we use a polyacrylamide hydrogel (PAA) to simulate the mechanical stress experienced by cells in scar tissue and investigate the impact of Emerin on cell behavior. We utilize atomic force microscopy (AFM) and RNA interference technology to analyze cell differentiation, migration, and stiffness. Our findings reveal that rigid substrates and cellular restriction elevate Emerin expression and diminish differentiation. Conversely, reducing Emerin expression leads to attenuated cell differentiation, where stiffness and constraining factors exert no notable influence. Furthermore, a softening of cells and an enhanced migration rate are also markedly observed. These observations indicate that variations in nuclear skeletal proteins, prompted by diverse matrix microenvironments, play a pivotal role in the pathogenesis of hypertrophic scars (HSs). This research offers novel insights and a reference point for understanding scar fibrosis formation mechanisms and preventing fibrosis.

Comparing Combination Triamcinolone Acetonide and 5-Fluorouracil with Monotherapy Triamcinolone Acetonide or 5-Fluorouracil in the Treatment of Hypertrophic Scars: A Systematic Review and Meta-Analysis

BACKGROUND

Keloids and hypertrophic scars cause physical and psychosocial problems. A combination of 5-fluorouracil (5-FU) and triamcinolone acetonide (TAC) may enhance the treatment of pathologic scars, although the evidence base is limited. The authors compared the efficacy and complication rates of combination intralesional TAC and 5-FU with those of monotherapy intralesional TAC or 5-FU for the treatment of keloids and hypertrophic scars.

METHODS

Embase, MEDLINE, and CENTRAL were searched by two independent reviewers. The primary outcome was treatment efficacy (51% to 100% improvement). Study quality and risk of bias were assessed using the Cochrane risk of bias tool.

RESULTS

Of 277 articles screened, 13 studies were included, comprising 12 randomized control trials and one nonrandomized study. Six studies compared combination intralesional therapy versus monotherapy 5-FU, and nine studies compared combination intralesional therapy versus monotherapy TAC. The combined group demonstrated superior objective treatment efficacy compared with the monotherapy TAC group (OR, 3.45; 95% CI, 2.22 to 5.35; I 2 = 0%; P < 0.00001) and monotherapy 5-FU group (OR, 4.17; 95% CI, 2.21 to 7.87; I 2 = 0%; P < 0.0001). Telangiectasia was less frequent in combination therapy (OR, 0.24; 95% CI, 0.11 to 0.52; I 2 = 0%; P = 0.0003) compared with monotherapy TAC.

CONCLUSIONS

Combined intralesional TAC and 5-FU administration demonstrated superior treatment efficacy outcomes compared with monotherapy TAC or 5-FU. Patient-reported outcome measures should be incorporated in the design of future research to justify clinical recommendations.

CLINICAL RELEVANCE STATEMENT

Combined TAC and 5-FU has demonstrated superior treatment efficacy outcomes compared to monotherapy TAC or 5-FU in the treatment of hypertrophic scars and keloids.

Quantitative comparison of three thyroidectomy approaches in neck muscles, voice, and swallowing functions

OBJECTIVE

This study compares endoscopic thyroidectomy by gasless unilateral axillary approach (ETGUA) and sternocleidomastoid leading-edge approach (SLEA) with conventional open thyroidectomy (COT) in hemithyroidectomy. The main focus is on the protection of neck muscles (sternocleidomastoid, omohyoid, sternothyroid) and the postoperative function of voice and swallowing yielded through these common approaches.

METHODS

A total of 302 patients who underwent hemithyroidectomy were enrolled and divided into three groups: ETGUA (n = 101), SLEA (n = 100), and COT (n = 101). Ultrasound was used to measure the thickness of bilateral neck muscles, including the sternocleidomastoid, omohyoid, and sternothyroid. The changes in thickness on the surgical side compared to the non-surgical side. Analyzed factors included muscle thickness changes, Swallowing Impairment Score (SIS), Voice Handicap Index (VHI), Scar Cosmesis Assessment and Rating (SCAR), Neck Injury Index (NII), surgery duration, drainage volume, hospitalization, and number of lymph nodes.

RESULTS

The clinical characteristics among the three groups were consistent except for differences in sex, age, and BMI. Metrics such as sternocleidomastoid muscle, NII, hypocalcemia, postoperative PTH, transient hoarseness, and number of lymph nodes showed no significant differences among the three groups. However, significant differences were found in the duration of surgery, drainage volume, hospitalization period omohyoid muscle, Sternohyoid muscle, VHI, SIS, and SCAR (all p < 0.001).

CONCLUSION

In comparison to COT, ETGUA and SLEA demonstrate superiority in protecting neck muscles and preserving voice and swallowing function without compromising surgical safety or radicality.

Endogenous stimuli-responsive separating microneedles to inhibit hypertrophic scar through remodeling the pathological microenvironment

Hypertrophic scar (HS) considerably affects the appearance and causes tissue dysfunction in patients. The low bioavailability of 5-fluorouracil poses a challenge for HS treatment. Here we show a separating microneedle (MN) consisting of photo-crosslinked GelMA and 5-FuA-Pep-MA prodrug in response to high reactive oxygen species (ROS) levels and overexpression of matrix metalloproteinases (MMPs) in the HS pathological microenvironment. In vivo experiments in female mice demonstrate that the retention of MN tips in the tissue provides a slowly sustained drug release manner. Importantly, drug-loaded MNs could remodel the pathological microenvironment of female rabbit ear HS tissues by ROS scavenging and MMPs consumption. Bulk and single cell RNA sequencing analyses confirm that drug-loaded MNs could reverse skin fibrosis through down-regulation of BCL-2-associated death promoter (BAD), insulin-like growth factor 1 receptor (IGF1R) pathways, simultaneously regulate inflammatory response and keratinocyte differentiation via up-regulation of toll-like receptors (TOLL), interleukin-1 receptor (IL1R) and keratinocyte pathways, and promote the interactions between fibroblasts and keratinocytes via ligand-receptor pair of proteoglycans 2 (HSPG2)-dystroglycan 1(DAG1). This study reveals the potential therapeutic mechanism of drug-loaded MNs in HS treatment and presents a broad prospect for clinical application.

Identification and validation of CCR5 linking keloid with atopic dermatitis through comprehensive bioinformatics analysis and machine learning

There is sufficient evidence indicating that keloid is strongly associated with atopic dermatitis (AD) across ethnic groups. However, the molecular mechanism underlying the association is not fully understood. The aim of this study is to discover the underlying mechanism of the association between keloid and AD by integrating comprehensive bioinformatics techniques and machine learning methods. The gene expression profiles of keloid and AD were downloaded from the Gene Expression Omnibus (GEO) database. A total of 449 differentially expressed genes (DEGs) were found to be shared in keloid and AD using the training datasets of GEO (GSE158395 and GSE121212). The hub genes were identified using the protein-protein interaction network and Cytoscape software. 20 of the most significant hub genes were selected, which were mainly involved in the regulation of the inflammatory and immune response. Through two machine learning algorithms of LASSO and SVM-RFE, CCR5 was identified as the most important key gene. Subsequently, upregulated CCR5 gene expression was confirmed in validation GEO datasets (GSE188952 and GSE32924) and clinical samples of keloid and AD. Immune infiltration analysis showed that T helper (Th) 1, 2 and 17 cells were significantly enriched in the microenvironment of both keloid and AD. Positive correlations were found between CCR5 and Th1, Th2 and Th17 cells. Finally, two TFs of CCR5, NR3C2 and YY1, were identified, both of which were downregulated in keloid and AD tissues. Our study firstly reveals that keloid and AD shared common inflammatory and immune pathways. Moreover, CCR5 plays a key role in the pathogenesis association between keloid and AD. The common pathways and key genes may shed light on further mechanism research and targeted therapy, and may provide therapeutic interventions of keloid with AD.

Combining scar-modulating agents for the treatment of hypertrophic scars and keloids: A systematic review

Injury to the skin can cause abnormal wound healing and continuous inflammation that leads to the formation of hypertrophic scars and keloids. These lesions often cause significant negative impact on a patient's life due to aesthetic, physical, social, and psychological consequences. Numerous treatment modalities exist for these hypertrophic scars and keloids, which include silicone sheeting, pressure garments, intralesional injection/topical application of scar-modulating agents, laser therapy, and surgical excision. Due to increased efficacy, an evolving treatment paradigm encourages the use of multiple treatment modalities instead of one treatment modality. However, no gold standard treatment exists for these lesions, leaving many people with unsatisfactory results. Adding scar-modulating agents such as 5-Fluorouracil, bleomycin, or Botulinum Toxin A to triamcinolone monotherapy has emerged as a potential drug combination for treating hypertrophic scars and keloids. We sought to critically analyze the evidence that exists for the use of more than one scar-modulating agent. This was done by conducting a systematic review to determine the efficacy of these combined drug regimens. We found that many of these combinations show evidence of increased efficacy and fewer/similar adverse events to triamcinolone monotherapy. Triamcinolone and 5-Fluorouracil showed the strongest and most consistent evidence out of all combinations. With this review, we intend to encourage more research into unique drug combinations that may improve outcomes for patients with symptomatic hypertrophic scars or keloids.

S-Nitrosylation-mediated coupling of DJ-1 with PTEN induces PI3K/AKT/mTOR pathway-dependent keloid formation

Background

Keloids are aberrant dermal wound healing characterized by invasive growth, extracellular matrix deposition, cytokine overexpression and easy recurrence. Many factors have been implicated as pathological causes of keloids, particularly hyperactive inflammation, tension alignment and genetic predisposition. S-Nitrosylation (SNO), a unique form of protein modification, is associated with the local inflammatory response but its function in excessive fibrosis and keloid formation remains unknown. We aimed to discover the association between protein SNO and keloid formation.

Methods

Normal and keloid fibroblasts were isolated from collected normal skin and keloid tissues. The obtained fibroblasts were cultured in DMEM supplemented with 10% fetal bovine serum and 1% penicillin/streptomycin. The effects of DJ-1 on cell proliferation, apoptosis, migration and invasion, and on the expression of proteins were assayed. TurboID-based proximity labelling and liquid chromatography-mass spectrometry were conducted to explore the potential targets of DJ-1. Biotin-switch assays and transnitrosylation reactions were used to detect protein SNO. Quantitative data were compared by two-tailed Student's t test.

Results

We found that DJ-1 served as an essential positive modulator to facilitate keloid cell proliferation, migration and invasion. A higher S-nitrosylated DJ-1 (SNO-DJ-1) level was observed in keloids, and the effect of DJ-1 on keloids was dependent on SNO of the Cys106 residue of the DJ-1 protein. SNO-DJ-1 was found to increase the level of phosphatase and tensin homolog (PTEN) S-nitrosylated at its Cys136 residue via transnitrosylation in keloids, thus diminishing the phosphatase activity of PTEN and activating the PI3K/AKT/mTOR pathway. Furthermore, Cys106-mutant DJ-1 is refractory to SNO and abrogates DJ-1-PTEN coupling and the SNO of the PTEN protein, thus repressing the PI3K/AKT/mTOR pathway and alleviating keloid formation. Importantly, the biological effect of DJ-1 in keloids is dependent on the SNO-DJ-1/SNO-PTEN/PI3K/AKT/mTOR axis.

Conclusions

For the first time, this study demonstrated the effect of transnitrosylation from DJ-1 to PTEN on promoting keloid formation via the PI3K/AKT/mTOR signaling pathway, suggesting that SNO of DJ-1 may be a novel therapeutic target for keloid treatment.

Comparing intralesional triamcinolone and verapamil-triamcinolone injections in keloids: A single-blinded randomised clinical trial

INTRODUCTION

In this clinical trial, we investigated the efficacy of two treatment methods for keloids resulting from surgical incisions: intralesional triamcinolone injections alone versus in combination with verapamil.

MATERIAL AND METHODS

Patients were divided into two groups: one received triamcinolone alone (Group T) and the other received a triamcinolone-verapamil blend (Group VT). Regular treatments were conducted until the keloids were nearly flat or for a maximum of eight sessions.

RESULTS

Both groups showed significant improvements, but Group VT saw quicker resolution of skin redness and needed fewer sessions. Though the Vancouver Scar Scale (VSS) scores were generally similar across both groups, Group VT exhibited greater improvements, leading to lower final scores. The VT group also attained normal scar flexibility faster than the T group.

CONCLUSION

These findings suggest that the combination of verapamil and triamcinolone provides a more effective treatment for keloids, thereby highlighting the potential of verapamil in scar reduction.

Subjective scar assessment scales in orthopaedic surgery and determinants of patient satisfaction: A systematic review of the literature

PURPOSE

Scar assessment tools can be utilized during the post-operative period to monitor scar progress. The primary aim of this systematic review was to evaluate current subjective scar assessment scales utilized in orthopaedic surgery. The secondary aim was to identify determinants of patients' satisfaction with their scars and evaluate current measurement scales.

METHODS

The preferred reporting items for systematic reviews and meta-analyses checklist was followed. Electronic databases, currently registered studies, conference proceedings and the reference lists of included studies were searched. There were no constraints based on language or publication status. A narrative synthesis provided a description and evaluation of scales utilized in orthopaedic surgery. Determinants of patient satisfaction were identified along with the scales used to measure satisfaction.

RESULTS

A total of 6059 records were screened in the initial search. Twenty-six articles satisfied the inclusion criteria, assessing 7130 patients. In the literature, six validated subjective scar scales were identified, including the Vancouver scar scale, patient and observer scar assessment scale, Manchester scar scale, Stony Brook scar evaluation scale, visual analogue scale, and Hollander wound evaluation scale. Studies utilizing these scales to evaluate scars following orthopaedic procedures did so successfully. These were total hip arthroplasty, total knee arthroplasty, and limb reconstruction. The scales demonstrated satisfactory validity. Functional outcomes such as restoration of movement ranked among patients' highest concerns. Scar cosmesis was found to be amongst patients' lowest priorities.

CONCLUSIONS

Subjective scar assessment scales identified in the literature were not designed specifically for orthopaedic surgery. However, these were able to appropriately assess scars in the studies identified in this review. Current evidence suggests the effect of scar cosmesis on patient satisfaction with orthopaedic procedures is limited.

Using Zhang's supertension-relieving suture technique with slowly-absorbable barbed sutures in the management of pathological scars: a multicenter retrospective study

Background

An ideal tension-relieving suture should be efficient for >3 months to retrieve normal tensile strength. Most preexisting suturing techniques provided tension elimination followed by relapse and scar proliferation due to absorption and cut-through of the sutures. This study introduces a simple but effective suture technique developed by a senior author (ZYX) to solve this problem.

Methods

A total of 120 patients with pathological scar (PS) had intervention treatment with the proposed suturing strategy at three centers from January 2018 to January 2021. A slowly absorbable 2-0 barbed suture was used for subcutaneous tension relieving with a set-back from the wound edge and a horizontal interval between proposed inserting points of 1 cm. The Patient and Observer Scar Assessment Scale (POSAS), scar width, perfusion and eversion of the wound edge were evaluated at 3-, 6- and 12-month follow-up. The time needed to place the tension-relieving suture was recorded and relapse was monitored for 18 months postoperatively.

Results

In total, 76 trunks, 32 extremities and 12 cervical PS were included, with an average subcutaneous tension-relieving suture time of 5 min. The Patient and Observer Scar Assessment Scale (POSAS) score decreased from 84.70 ± 7.06 preoperatively to 28.83 ± 3.09, 26.14 ± 1.92 and 24.71 ± 2.00 at 3, 6 and 12 months postoperatively, respectively (p < 0.0001). The scar widths were 0.17 ± 0.08, 0.25 ± 0.09 and 0.33 ± 0.10 cm, respectively, with perfusion significantly decreased from 213.64 ± 14.97 to 112.23 ± 8.18 at 6 months (p < 0.0001). The wound edge flattened out during the first 3 months in most cases with only two scar relapses.

Conclusions

Zhang's suture technique provides a rapid and long-lasting tension-relieving effect with ideal scar appearances and lower relapse rates in the surgical management of PS.

Extracellular Targets to Reduce Excessive Scarring in Response to Tissue Injury

Excessive scar formation is a hallmark of localized and systemic fibrotic disorders. Despite extensive studies to define valid anti-fibrotic targets and develop effective therapeutics, progressive fibrosis remains a significant medical problem. Regardless of the injury type or location of wounded tissue, excessive production and accumulation of collagen-rich extracellular matrix is the common denominator of all fibrotic disorders. A long-standing dogma was that anti-fibrotic approaches should focus on overall intracellular processes that drive fibrotic scarring. Because of the poor outcomes of these approaches, scientific efforts now focus on regulating the extracellular components of fibrotic tissues. Crucial extracellular players include cellular receptors of matrix components, macromolecules that form the matrix architecture, auxiliary proteins that facilitate the formation of stiff scar tissue, matricellular proteins, and extracellular vesicles that modulate matrix homeostasis. This review summarizes studies targeting the extracellular aspects of fibrotic tissue synthesis, presents the rationale for these studies, and discusses the progress and limitations of current extracellular approaches to limit fibrotic healing.

Harvesting anterior iliac crest or calvarial bone grafts to augment severely resorbed edentulous jaws: a systematic review and meta-analysis of patient-reported outcomes

The aim of this systematic review was to compare patient-reported outcomes after harvesting calvarial or anterior iliac crest bone grafts to repair severe jaw defects and enable implant placement. The MEDLINE, Embase, Cochrane Central Register of Controlled Trials databases, and OpenGrey were searched for studies on patient satisfaction, pain, disturbances in daily functioning, sensory alterations, donor site aesthetics, and complication rates. Of the 1946 articles identified, 43 reporting 40 studies fulfilled the inclusion criteria; the studies were one randomized controlled clinical trial, one retrospective controlled clinical trial, and 23 prospective and 15 retrospective cohort studies. A meta-analysis of two studies (74 patients) showed no difference in satisfaction (mean difference (MD) - 0.13, 95% confidence interval (CI) - 1.17 to 0.92; P = 0.813) or postoperative pain (directly postoperative: MD -2.32, 95% CI -5.20 to 0.55, P = 0.113; late postoperative: MD -0.01, 95% CI -0.14 to 0.11, P = 0.825) between donor sites. However, the level of evidence is limited, due to the retrospective, non-randomized design of one study. Postoperative gait disturbances were highly prevalent among the anterior iliac crest patients (28-100% after 1 week). The incidence rates of sensory disturbances and other complications were low, and the donor site aesthetic outcomes were favourable for both graft types. To conclude, harvesting bone grafts from the calvarium or anterior iliac crest to augment the severely resorbed edentulous jaw results in similar patient satisfaction. However, the findings for postoperative pain and disturbances in daily living suggest a trend in favour of calvarial bone grafts if harvested using an adjusted technique.

Pluronic F127-liposome-encapsulated curcumin activates Nrf2/Keap1 signaling pathway to promote cell migration of HaCaT cells

Curcumin (CUR) is an extract of Curcuma longa Linn., which has various pharmacological activities. The instability, low water solubility and bioavailability of CUR greatly limit its clinical application. This work prepared Pluronic F127-liposome-encapsulated curcumin (CUR-LIP-F127) and explored its functional role in wound healing. Liposome-encapsulated curcumin (CUR-LIP) and CUR-LIP-F127 were prepared. Human keratinocyte cell line (HaCaT) was treated with CUR, Pluronic F127-liposome (LIP-F127) and CUR-LIP-F127, or combined with ML385 (Nrf2 inhibitor). The expression of mRNAs and proteins was detected by quantitative real-time PCR and western blotting. MTT and wound healing assays were performed to detect cell viability and migration. CUR, LIP-F127 and CUR-LIP-F127 all had no influence on cell viability of HaCaT cells. CUR-LIP-F127 treatment significantly accelerated cell migration and enhanced the expression of nuclear factor erythroid-related factor 2 (Nrf2) and kelch-like erythroid cell-derived protein 1 (Keap1) in HaCaT cells with respect to CUR or LIP-F127 treatment. ML385 treatment impaired CUR-LIP-F127-mediated promotion of migration and up-regulation of Nrf2 and Keap1 in HaCaT cells. This work demonstrated that CUR-LIP-F127 activated Nrf2/Keap1 signaling pathway to promote migration of HaCaT cells, suggesting that CUR-LIP-F127 may contribute to wound healing.

Could hyperbaric oxygen be an effective therapy option for pathological scars? A systematic review and meta-analysis

BACKGROUND

Hyperbaric oxygen (HBO) therapy involves breathing pure oxygen or a high oxygen concentration above atmospheric (ATM) pressure in an enclosed chamber. Studies on pathological scars have demonstrated that HBO can inhibit the formation of pathological scars.

OBJECTIVE

To evaluate the efficacy of HBO in the treatment of pathological scars via meta-analysis.

METHODS

Searches were run on various databases, including the Cochrane, Embase, PubMed, Web of Science, and CNKI databases. A comparative study was conducted on patients with pathological scars treated with or without HBO. We used RevMan 5.4 software to determine the recurrence rate, treatment satisfaction, and Vancouver Scar Scale(VSS) score in the pathological scar.

RESULTS

A total of 543 publications were identified; after screening, four were selected for review, including one randomized controlled trial (RCT), one controlled clinical trial (CCT), and two retrospective cohort studies. Meta-analysis results showed that HBO treatment reduced the pathological scar recurrence rate after surgery and radiotherapy (OR = 0.26, 95% CI: 0.13-0.52, p = 0.0001). Patients had higher satisfaction after HBO therapy (OR = 4.45, 95% CI: 1.49-13.30, p = 0.007). The Vancouver scar scale (VSS) score of patients with pathological scars was significantly improved in the HBO group (SMD: -3.82, 95% CI: -6.07to -0.49, p = 0.02).

CONCLUSIONS

HBO treatment decreased the recurrence rate of pathological scars after surgery and radiotherapy, increased patient satisfaction, and reduced the VSS score, thus providing a new way to treat pathological scar hyperplasia. However, evaluation of the longer-term effects of HBO treatment requires further comprehensive studies, including more RCTs.

Keloid Treatment Using Plasma Exeresis: A Pilot Trial Study

Introduction: Keloid scars and hypertrophic scars are more commonly seen after surgeries, suture placements, or other skin damages. Scars can be treated using a variety of methods, including topical compounds, surgery, and lasers. The aim of this study is to evaluate the effects of plasma exeresis on the treatment of keloid scars. Methods: This experimental study was conducted on patients with keloid scars, defined as a treatment-resistant subtype of scars with extension beyond the primary skin defect and cauliflower appearance, in different parts of the body. The patients were treated with 2-to-3-session plasma exeresis. Scars were examined based on the Vancouver scar scale (VSS) before and 5 months after the treatment. Results: A total number of 24 scars were enrolled in this study. The number of patients was 16. There was a decrease in the mean thickness of keloids from 2.20 to 0.54 (P=0.000). The mean pigmentation and pliability scores decreased from 1.54 and 2.16 to 0.375 and 0.541, respectively (P=0.001, 000). There was a significant reduction in the keloid scar vascularity score from 1.666 to 0.541 (P=0.000). There was a decrease from 0.708 to 0.00 (P=0.004) in the mean itchiness score. After the intervention, the mean pain score was 0.000, compared to 0.7500 before the intervention (P=0.003). There was a decrease in the total score from 8.958 to 2.000 (P=0.000). Conclusion: The plasma exeresis procedure is effective in destroying small keloid scars. Furthermore, results in less itching and pain, as well as no significant complications or recurrences.

Visible light-driven photodynamic therapy for hypertrophic scars with MOF armored microneedles patch

Photodynamic therapy (PDT) is widely used for the treatment of hypertrophic scars in clinical practice. However, the low transdermal delivery of photosensitizers in scar tissue and protective autophagy induced by Photodynamic therapy greatly reduces the therapeutic efficiency. Therefore, it is necessary to deal with these difficulties for overcoming obstacles in Photodynamic therapy treatment. In this study, a photosensitizer with photocatalytic performance was designed and synthesized using innovative MOFs (metal-organic frameworks). Additionally, the MOFs, together with an autophagy inhibitor chloroquine (CQ), was loaded in a high mechanical strength microneedle patch (MNP) for transdermal delivery. With these functionalized MNP, photosensitizers and chloroquine were delivered deep inside hypertrophic scars. Inhibition of autophagy increases the levels of reactive oxygen species (ROS) under high-intensity visible-light irradiation. Multiprong approaches have been used to remove obstacles in Photodynamic therapy and successfully enhance its anti-scarring effect. In vitro experiments indicated that the combined treatment increased the toxicity of hypertrophic scar fibroblasts (HSFs), downregulated the level of collagen type I expression as well as transforming growth factor-β1 (TGF-β1)expression, decreased the autophagy marker protein LC3II/I ratio, increased the expression of P62. In vivo experiments showed that the MNP had good puncture performance, and significant therapeutic effects were observed in the rabbit ear scar model. These results indicate that functionalized MNP has high potential clinical value.

CO2 fractional laser combined with triamcinolone acetonide injection for the hypertrophic scars: which is first?

The aim of this study is to investigate and analyze the effect of different application sequences of CO2 fractional laser and triamcinolone acetonide injection on the application effect of hypertrophic scar in one operation. Patients with hypertrophic scars who received CO2 lattice laser combined with triamcinolone acetonide injection from January 2021 to December 2022 were retrospectively analyzed. According to the different initial operations, they were divided into CO2 FL-TA group and TA-CO2 FL group. The Vancouver Scar Scale score and scar thickness of the two groups before and after treatment were analyzed. The complications occurred in the two groups during the treatment period. The clinical efficacy of the two groups before and after the treatment was calculated. Before treatment, there was no difference in scar thickness and VSS score between the two groups (P > 0.05). After treatment, the above indexes in CO2 FL-TA group were significantly better than those in TA-CO2 FL group (P < 0.05); the incidence of adverse reactions in CO2 FL-TA group was 9.38%, which was significantly lower than that in TA-CO2 FL group (18.75%) (P < 0.05); the total effective rate of CO2 FL-TA group was 90.63%, which was significantly higher than that in TA-CO2 FL group (65.63%) (P < 0.05). In the process of combined CO2 fractional laser and triamcinolone acetonide injection in the treatment of hypertrophic scars, CO2 fractional laser treatment first, and then triamcinolone acetonide injection can reduce the number of treatments, reduce the incidence of adverse reactions, and achieve more satisfactory treatment effect.

Metformin Improves Burn Wound Healing by Modulating Microenvironmental Fibroblasts and Macrophages

Metformin, a biguanide, exerts different functions through various signaling pathways. In order to investigate the function and mechanism of metformin in burn wounds, we established burn rat models, subcutaneously injected metformin to treat the wounds, and observed the morphologies and the expression of collagen I, collagen III, fibronectin, and pro-inflammatory markers. In vitro experiments were performed to investigate the effects of metformin on the proliferation, migration, and collagen I synthesis of the mouse embryonic fibroblast (NIH 3T3) cell line and on the proliferation, apoptosis, and immune response of the mouse mononuclear macrophage (RAW 264.7) cell line. Finally, we studied the regulatory effects of metformin on a co-culture of RAW 264.7/NIH 3T3 cells. We found that 100 mM of metformin reduced dermal thickness, collagen I deposition, and mRNA expression of IL1β and CCL2 in rat burn wounds. In vitro experiments revealed that metformin inhibited the proliferation of NIH 3T3 and RAW 264.7 cells. Metformin attenuated NIH 3T3 cell migration via the AMPK/mTOR pathway and attenuated collagen I synthesis through the TGFβ1/Smad3 pathway. Metformin inhibited the apoptosis of RAW 264.7 cells induced by 10 μg/mL LPS. Metformin downregulated the mRNA expression of IL1β and CCL2 in RAW 264.7 cells under 1 μg/mL LPS induction by inhibiting NF-κB p65 phosphorylation. In a RAW 264.7/NIH 3T3 co-culture, metformin attenuated collagen I synthesis in NIH 3T3 cells by inhibiting RAW 264.7 paracrine secretion of TGF-β1. This provides new evidence related to the development of metformin for potentially improving burn wound healing.

Clinical application of absorbable collagen thread and cosmetic suture technique in emergency treatment of children's facial trauma

AIM

To explore the effect of absorbable collagen thread and cosmetic suture technique on scar inhibition after emergency facial trauma in children, and to explore the application value of absorbable collagen thread in emergency facial trauma.

METHODS

Children who received emergency treatment of facial trauma in plastic surgery department from January 2021 to January 2022 were analysed retrospectively, and were divided into absorbable collagen thread group and non-absorbable nylon thread group. The general data, scar appearance and local symptoms of the two groups were analysed, and the scar appearance was scored by scar beauty rating scale and non-inferiority test was analysed statistically.

RESULTS

A total of 632 children with facial trauma were included in this study, including 458 patients with absorbable collagen thread and 174 patients with non-absorbable nylon thread. The SCAR score of the absorbable collagen thread group (3.03 ± 1.57) was similar to that of the non-absorbable nylon thread group (2.98 ± 2.39) (95% confidence interval), and the final scar outcome score was not statistically different (P > 0.05). All families of the patients were satisfied with the results of the procedure, 95% very satisfied.

CONCLUSION

The use of absorbable collagen thread and cosmetic suture technique to treat the wounds of children with facial emergency trauma, resulted in good wound healing, little scar expansion, low incidence of erythema and pigment abnormality, no obvious surgical trace, and no scar hypertrophy or atrophy. The overall impression was good, the pain of stitch removal was avoided for children's patients, and the satisfaction of family members was high. Cosmetic suture technique with absorbable sutures is worthy of clinical application.

Comparative Study Between the Mini-Open (≤2.5 Cm) Approach and Conventional Open Lateral Approach in the Surgical Treatment of Radial Head Fractures

Purpose

The conventional lateral approach is widely used to treat radial head fractures with screws. However, the traditional incision may have shortcomings, including excessive exposure and significant scarring. We propose an innovative method – a mini-open lateral approach of less than 2.5 cm for surgical treatment of radial head fractures with screws.

Methods

From Jan 2017 to Dec 2020, 34 patients diagnosed with closed radial head fracture were treated with open reduction and internal fixation (ORIF) in this study. The novel group (mini-open group) included 15 patients, and the other 19 patients were in the traditional group. The time of operation and the blood loss during operation were recorded. Postoperative clinical outcomes and radiographic results were recorded and compared between the two groups. The range of motion (ROM) in the elbow, the Visual Analogue Scale (VAS), the Mayo Elbow Performance Score (MEPS), Rating Scale of the American Shoulder and Elbow Surgeons (ASES), and the Shortened Disabilities of the Arm, Shoulder and Hand Questionnaire (Q-DASH) score and complications, such as wound infection, vascular and nerve damage, and fragment redisplacement were observed in the two groups.

Results

In the comparison between the two groups, there was no significant difference in age, sex, cause of radial head fracture, or other basic information. The operation time, intraoperative blood loss, and VAS score at 3 days postoperation were significantly reduced in the novel group (p < 0.05). The follow-up results showed that there was no significant difference in MEPS, ASES, or Q-DASH scores between the two groups.

Conclusion

The mini-open approach reduced intraoperative blood loss, shortened operation time, relieved patient pain, and achieved a satisfactory postoperative clinical result, which demonstrates that the novel approach is a safe and effective option for treating radial head fractures.

Luminescence and Preventive Effect of Two New Cd(II) Compounds on Scar Formation after Cosmetic Surgery

Two coordination polymers involving Cd(II), i.e., [Cd2(IDPA)2(bpe) (H2O)2]n·2n(H2O) (1) (H2IDPA is 5-(1-oxoisoindolin-2-yl)isophthalic acid, bpe is 1,2-bis(4-pyridyl)ethane, 4-bpmh is N, N-bis-pyridin-4-ylmethylene-hydrazine), and [Cd(IDPA)(4-bpmh)0.5(H2O)2]n·n(H2O) (2) are prepared under solvothermal conditions via tuning the auxiliary ligand from bpe to 4-bpmh. Moreover, the as-prepared complexes 1–2 reveal much stronger luminescence in contrast to that of the free organic ligands. Their preventive effect and mechanism on scar formation after cosmetic surgery was explored. First, the two complexes’ suppression of the viability of the human immortal keratinocyte line (HaCaT) cell line was examined via exploiting cell counting kit-8 (CCK-8) detection. The vascular endothelial growth factor (VEGF) signal pathway activation in HaCaT cells was detected by real-time reverse transcription-polymerase chain reaction (RT-PCR) assay.

Identification of a Diagnostic Signature and Immune Cell Infiltration Characteristics in Keloids

Background: Keloid disorder is a recurrent fibroproliferative cutaneous tumor. Due to the lack of early identification of keloid patients before the formation of keloids, it is impossible to carry out pre-traumatic intervention and prevention for these patients. This led us to identify and determine signatures with diagnostic significance for keloids.

Methods: Public series of matrix files were downloaded from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) were calculated from expression profiling data, and the diagnostic signature was identified by constructing a protein-protein interaction (PPI) network. The diagnostic efficacy of the screened signature was assessed by employing receiver operating characteristic (ROC) curves. Furthermore, we calculated the proportion of different immune cells in the gene expression matrix microenvironment by the “ssGSEA” algorithm, and assessed the difference in immune cell abundance between keloids and control groups and the relationship between the signature and immune cell infiltration. Clinical keloid and normal skin tissues were collected, and the expression of the screened diagnostic signature was validated by RT-qPCR and immunohistochemical assay.

Results: By screening the key genes in PPI, TGM2 was recognized and validated as a diagnostic signature and the infiltrating abundance of 10 immune cells was significantly correlated with TGM2 expression. Gene ontology enrichment analysis demonstrated that TGM2 and molecules interacting with it were mainly enriched in processes involving wound healing and collagen fiber organization. TGM2 correlated positively with HIF-1A (R = 0.82, p-value = 1.4e-05), IL6 (R = 0.62, p-value = 0.0053), and FN1 (R = 0.66, p-value = 0.0019). Besides, TGM2 was significantly upregulated in clinical keloid samples compared to normal skin tissues.

Conclusion: TGM2 may serve as an auxiliary diagnostic indicator for keloids. However, the role of TGM2 in keloids has not been adequately reported in the current literature, which may provide a new direction for molecular studies of keloids.

Current Advances in RNA Therapeutics for Human Diseases

Following the discovery of nucleic acids by Friedrich Miescher in 1868, DNA and RNA were recognized as the genetic code containing the necessary information for proper cell functioning. In the years following these discoveries, vast knowledge of the seemingly endless roles of RNA have become better understood. Additionally, many new types of RNAs were discovered that seemed to have no coding properties (non-coding RNAs), such as microRNAs (miRNAs). The discovery of these new RNAs created a new avenue for treating various human diseases. However, RNA is relatively unstable and is degraded fairly rapidly once administered; this has led to the development of novel delivery mechanisms, such as nanoparticles to increase stability as well as to prevent off-target effects of these molecules. Current advances in RNA-based therapies have substantial promise in treating and preventing many human diseases and disorders through fixing the pathology instead of merely treating the symptomology similarly to traditional therapeutics. Although many RNA therapeutics have made it to clinical trials, only a few have been FDA approved thus far. Additionally, the results of clinical trials for RNA therapeutics have been ambivalent to date, with some studies demonstrating potent efficacy, whereas others have limited effectiveness and/or toxicity. Momentum is building in the clinic for RNA therapeutics; future clinical care of human diseases will likely comprise promising RNA therapeutics. This review focuses on the current advances of RNA therapeutics and addresses current challenges with their development.

Complexing the Pre-assembled Brush-like siRNA with Poly(β-amino ester) for Efficient Gene Silencing

Small interfering RNA (siRNA) has been emerging as a highly selective and effective pharmaceutics for treating broad classes of diseases. However, the practical application of siRNA agent is often hampered by its poor crossing of the cellular membrane barrier and ineffective releasing from endosome to cytoplasm, leading to low gene silencing efficacy for clinical purposes. Thus far, cationic lipid and polymer-based vectors have been extensively explored for gene delivery. Yet condensing the rigid and highly negatively charged siRNA duplex to form a stable complex vehicle usually requires a large load of cationic carriers, prone to raising the toxicity issue for delivery. Herein, we develop a simple strategy that can efficiently condense the siRNAs into nanoparticle vehicles for target gene regulation. In this approach, we first employ a DNA-grafted polycaprolactone (DNA-g-PCL) brush as template to organize the small rigid siRNAs into a large brush-like structure (siRNA-brush) through nucleic acid hybridization. Then, the siRNA-brush assembly is condensed by an ionizable and biodegradable polymer (poly(β-amino ester), PBAE) under acidic buffer condition to form a stable nanoparticle for siRNA delivery. Compared to the free siRNAs with poor complexing capability with PBAE, the large brush-like siRNA assemblies with more complicated topological architecture significantly promotes their electrostatic interaction with PBAE, enabling the formation of complexed nanoparticles at low weight ratio of polymer to siRNA. Additionally, PBAE/siRNA-brush complexes exhibit good biocompatibility and stability under physiological condition, as well as enhanced cellular internalization. When equipped with functional siRNAs, the obtained delivery system demonstrates excellent downregulation of target genes both in vitro and in vivo, through which the progression of hypertrophic scars can be retarded with negligible adverse effects in an xenografted mouse model.

TREATMENT WITH THERESIENöL OF SURGICAL DISEASES OF THE SKIN

Theresienöl is a 100 % natural product representing a mixture of animal and vegetable raw materials from Tyrol. Its exact recipe has been preserved untouched and in deep secret for more than six centuries yet, and has been passed down from generation to generation. Six patients were included in this case series one patient with malignant melanoma of the skin after re-excision with subsequent non-free skin surgical plastic, two patients with III degree skin burning and three patients with infected wound successfully treated with Theresienöl. All of them - before the application of Theresienöl - were treated with different operative methods. The treatment of scars from operative interventions with Theresienöl is very effective. That is why it must start directly after the operative intervention. The therapeutic effect of Theresienöl for postoperative scars is commensurable with and even better than the one of all applied until now local medicines, which makes it an agent of choice in those cases. Theresienöl represents a good alternative to the free skin surgical plastic for small burns of III degree. The local treatment of infected wounds with Theresienoil is more effective and economically sound than the treatment with all the rest types of dressings. The effects from the treatment of different surgical diseases with Theresienöl occur very rapidly, while there is a very good response to local hematomas, pain, and itchiness by the medicine, and there are no side effects from its administration.

Keloid fibroblasts have elevated and dysfunctional mechanotransduction signaling that is independent of TGF-β

BACKGROUND

Fibroblasts found in keloid tissues are known to present an altered sensitivity to microenvironmental stimuli. However, the impact of changes in extracellular matrix stiffness on phenotypes of normal fibroblasts (NFs) and keloid fibroblasts (KFs) is poorly understood.

OBJECTIVES

Investigation the impact of matrix stiffness on NFs and KFs mainly via detecting yes-associated protein (YAP) expression.

METHODS

We used fibronectin-coated polyacrylamide hydrogel substrates with a range from physiological to pathological stiffness values with or without TGF-β (fibrogenic inducer). Atomic force microscopy was used to measure the stiffness of fibroblasts. Cellular mechanoresponses were screened by immunocytochemistry, Western blot and Luminex assay.

RESULTS

KFs are stiffer than NFs with greater expression of α-SMA. In NFs, YAP nuclear translocation was induced by increasing matrix stiffness as well as by stimulation with TGF-β. In contrast, KFs showed higher baseline levels of nuclear YAP that was not responsive to matrix stiffness or TGF-β. TGF-β1 induced p-SMAD3 in both KFs and NFs, demonstrating the pathway was functional and not hyperactivated in KFs. Moreover, blebbistatin suppressed α-SMA expression and cellular stiffness in KFs, linking the elevated YAP signaling to keloid phenotype.

CONCLUSIONS

These data suggest that whilst normal skin fibroblasts respond to matrix stiffness in vitro, keloid fibroblasts have elevated activation of mechanotransduction signaling insensitive to the microenvironment. This elevated signaling appears linked to the expression of α-SMA, suggesting a direct link to disease pathogenesis. These findings suggest changes to keloid fibroblast phenotype related to mechanotransduction contribute to disease and may be a useful therapeutic target.

Feasibility of aponeurectomy in combination with perioperative 192Ir high dose rate brachytherapy for Dupuytren's disease

PURPOSE

Partial aponeurectomy (PA) is a standard procedure for Dupuytren's contracture (DC). Here we report a novel approach using surgery combined with perioperative high dose rate (¹⁹²Ir-HDR) brachytherapy.

METHODS AND PATIENTS

From March 2018 until February 2020, thirteen rays of 6 patients with Dupyutren's contractures underwent PA followed by HDR brachytherapy. After removal of fibrous tissue and mobilization of the tendons, one to three catheters per patient were placed intraoperatively. Immediately after surgery, a planning computer tomography with 3D-planning was performed. Then 10-12 Gy were given to 0-2 mm from the catheters' surface and the catheters were removed 6-12 h after brachytherapy.

RESULTS

No complications were observed. The mean contractures were reduced from 55.4° (standard error SE 19.6) to 15.4° (SE 6.7; p < 0.01). One patient showed progressive fibrosis of a nontreated ray during follow-up.

CONCLUSIONS

HDR brachytherapy in combination with surgery is feasible and harbors the potential for combined modality therapy to reduce relapse rates of advanced or relapsing DC. Controlled studies are warranted to investigate the role of bimodal therapy compared with PA alone.

Mechanisms of reducing joint stiffness by blocking collagen fibrillogenesis in a rabbit model of posttraumatic arthrofibrosis

Posttraumatic fibrotic scarring is a significant medical problem that alters the proper functioning of injured tissues. Current methods to reduce posttraumatic fibrosis rely on anti-inflammatory and anti-proliferative agents with broad intracellular targets. As a result, their use is not fully effective and may cause unwanted side effects. Our group previously demonstrated that extracellular collagen fibrillogenesis is a valid and specific target to reduce collagen-rich scar buildup. Our previous studies showed that a rationally designed antibody that binds the C-terminal telopeptide of the α2(I) chain involved in the aggregation of collagen molecules limits fibril assembly in vitro and reduces scar formation in vivo. Here, we have utilized a clinically relevant arthrofibrosis model to study the broad mechanisms of the anti-scarring activity of this antibody. Moreover, we analyzed the effects of targeting collagen fibril formation on the quality of healed joint tissues, including the posterior capsule, patellar tendon, and subchondral bone. Our results show that blocking collagen fibrillogenesis not only reduces collagen content in the scar, but also accelerates the remodeling of healing tissues and changes the collagen fibrils’ cross-linking. In total, this study demonstrated that targeting collagen fibrillogenesis to limit arthrofibrosis affects neither the quality of healing of the joint tissues nor disturbs vital tissues and organs.

Operative choice for displaced proximal humeral fractures in adolescents with open visible physis: A comparative study of external fixator vs. Kirschner wire

BACKGROUND

For adolescents with severely displaced proximal humeral fracture (PHF), surgery is a good choice yielding excellent outcomes, and Kirchner wire (KW) is a cost-effective choice for fixation. Purpose of this study is to compare the clinical outcomes of external fixator (EF) and KW for the treatment of PHF in adolescents.

METHODS

Patients of PHF operated at our institute, from January 2008 to January 2016, were reviewed retrospectively. Demographic data, including sex, age at the time of surgery, operated side, and hardware choice, were collected from the hospital database. Preoperative radiographs were reviewed and classified according to Neer-Horwitz classification. Shoulder function was evaluated at the last follow-up using the American Shoulder and Elbow Surgeons (ASES) score. Complications, including infection, malunion, nonunion, stiffness of the shoulder joint, and failure of fixation were also recorded.

RESULTS

Thirty-five patients, including 23 males and 12 females, were included in the EF group, whereas 40 patients, including 25 males and 15 females, were included in the KW group (P = 0.867). The average age of patients in the EF group was 13.3 ± 1.7 years, and that of KW was 13.6 ± 1.8 years (P = 0.409). Patients in both groups were followed-up for at least 12 months. The operative time in the EF group (42.4 ± 11.2 min) was significantly shorter than those in the KW group (54 ± 13.6 min) (P < 0.001). The frequency of fluoroscopy in the EF group (12 ± 2.4 times) was significantly less than those in the KW group (17 ± 2.8 times (P < 0.001). The rate of open reduction was significantly higher in KW (35%) group than those in the EF group (0%) (P < 0.001). There was no case of nonunion and malunion in both groups.

CONCLUSION

External fixator is superior to Kirschner wire in the treatment of proximal humeral fractures in adolescents with shorter operative time and lower rate of open reduction with comparable clinical outcomes.

Comparative efficacy and safety of verapamil and triamcinolone in keloid and hypertrophic scar treatment: a meta-analysis

Keloids and hypertrophic scars are harmful to physical and psychological health. The study aims to compare the efficacy and safety of verapamil and triamcinolone in the treatment of keloids and hypertrophic scars. Relevant publications were searched from PubMed, Embase, Cochrane library, CNKI, Weipu, and Wanfang databases. Results were expressed as weighted mean differences (WMDs) or the relative ratios (RRs) with 95% confidence interval (CI). Pooled estimates were calculated using random-effects or fixed-effects models according to the heterogeneity among studies. The pooled results indicated that the triamcinolone treatment showed significantly better effectiveness in height (at 12, 15, 18, 21, and 24 weeks), pliability (at 3, 6, 9, 21, and 24 weeks) and vascularity (at 3, 6, 9, and 12 week) than that of verapamil (P < .05). Moreover, the side effects such as skin atrophy (RR = 0.13, 95% CI: 0.04 to 0.42, P = .001), telangiectasia (RR = 0.08, 95% CI: 0.02 to 0.28, P < .001), and hyperpigmentation (RR = 0.12, 95% CI: 0.03 to 0.44, P = .001) of verapamil were significantly less than those in triamcinolone. This meta-analysis showed that triamcinolone had a better therapeutic efficacy than verapamil, while verapamil was more safety.

Effect of THBS1 on the Biological Function of Hypertrophic Scar Fibroblasts

Hypertrophic scarring is a skin collagen disease that can occur following skin damage and is unlikely to heal or subside naturally. Since surgical treatment often worsens scarring, it is important to investigate the pathogenesis and prevention of hypertrophic scarring. Thrombospondin-1 (THBS1) is a matrix glycoprotein that can affect fibrosis by activating TGF-β1, which plays a key role in wound repair and tissue regeneration; therefore, we investigated the effects of THBS1 on the biological function of hypertrophic scar fibroblasts. THBS1 expression was measured in hypertrophic scars and adjacent tissues as well as normal fibroblasts, normal scar fibroblasts, and hypertrophic scar fibroblasts. In addition, THBS1 was overexpressed or silenced in hypertrophic scar fibroblasts to determine the effects of THBS1 on cell proliferation, apoptosis, and migration, as well as TGF-β1 expression. Finally, the role of THBS1 in hypertrophic scarring was confirmed in vivo using a mouse model. We found that THBS1 expression was increased in hypertrophic scar tissues and fibroblasts and promoted the growth and migration of hypertrophic scar fibroblasts as well as TGF-β1 expression. Interestingly, we found that si-THBS1 inhibited the occurrence and development of bleomycin-induced hypertrophic scars in vivo and downregulated TGF-β1 expression. Together, our findings suggest that THBS1 is abnormally expressed in hypertrophic scars and can induce the growth of hypertrophic scar fibroblasts by regulating TGF-β1. Consequently, THBS1 could be an ideal target for treating hypertrophic scarring.