Scar Tissue Formation Research Articles

Comparison of the Efficacy of Human Umbilical Cord-Derived and Bone Marrow Aspirate Concentrate Mesenchymal Stem Cells for Cartilage Repair Defects of the Knee via Arthroscopic Implementation on Scaffolds in a Retrospective Study.

Injuries to the articular cartilage of the human knee joint, commonly resulting from trauma, inflammation, or age- and activity-related wear and tear, have significant implications, primarily leading to osteoarthritis (OA). Conservative treatments for such injuries often yield suboptimal clinical outcomes. Surgical interventions using current methods may not consistently provide satisfactory results, largely due to the formation of low-quality scar tissue lacking the biomechanical properties of hyaline cartilage. In this retrospective study, we compared the results of two promising methods for regenerating cartilage defects in the knee joints using scaffolds soaked with stem cells of different origins: bone marrow aspirate concentrate mesenchymal stem cells (BMAC-MSCs) and human umbilical cord-derived mesenchymal stem cells (hUCB-MSCs). We evaluated 39 patients (39 knees, hUCB-MSCs: 20 knees, BMAC: 19 knees) at the 12-month follow-up using VAS, KOOS, Lysholm scales and radiologically with M-MOCART 2.0 score. The analysis demonstrated substantial overall improvement in both groups, notably reflected in enhanced quality of life for the patients. Interestingly, the final scores in the hUCB-MSCs group were comparable to those in the BMAC-MSCs group, with no statistically significant differences observed, despite variations in preoperative age and lesion size. Notably, the hUCB-MSCs group consisted of significantly older individuals with larger lesion sizes. Both procedures were found to be safe, and improvement was observed in both groups, which holds promise for future clinical investigations.

Study design of BI 1015550 for idiopathic pulmonary fibrosis and progressive pulmonary fibrosis: a plain language summary

What is this summary about? Two ongoing clinical studies are part of a programme called FIBRONEER. The FIBRONEER studies are testing the drug BI 1015550 as a treatment for people with idiopathic pulmonary fibrosis (IPF) and people with progressive pulmonary fibrosis (PPF). IPF is a severe lung disease where scar tissue builds up in the lungs. The ‘idiopathic’ part means that doctors do not know the cause of the lung scarring. PPF is a general term to describe the worsening of lung scarring in any disease where scar tissue forms in the lungs, both from known causes such as other underlying diseases and for unknown reasons. While IPF can be considered to be a typical form of worsening lung scarring, in clinical studies, IPF and PPF are usually considered separately. In both IPF and PPF, scar tissue builds up in the lungs, making them smaller and no longer able to take in oxygen well. This leads to difficulty in breathing and getting oxygen to the tissues, making it difficult to perform daily activities and reducing the patient's quality of life. The symptoms and outcomes of PPF are often similar to IPF. What study drug is being investigated? BI 1015550 is a new study drug being developed to reduce scarring in the lungs in IPF and PPF. In the FIBRONEER studies, some participants are taking BI 1015550 and others are taking placebo. The placebo looks identical to BI 1015550 but does not contain any medicine. Researchers will compare the study drug to placebo to find out how well the study drug works. Participants may also take another approved medicine to treat their lung scarring. The FIBRONEER studies are investigating the effects of BI 1015550 alone and in combination with any existing medicines the participants are taking. The goal is to see whether BI 1015550 can slow down or stop a decline in lung function in people with IPF and PPF, and how well it is tolerated.

Therapeutic Potential in Wound Healing of Allogeneic Use of Equine Umbilical Cord Mesenchymal Stem Cells.

Wound healing after skin injury is a complex process, particularly in equines where leg wounds are prevalent and their repair is complicated due to the anatomical characteristics. Conventional treatments are not effective enough. The umbilical cord offers an unlimited source of adult mesenchymal stem cells (ucMSCs) from Wharton's jelly tissue. The present study aims to demonstrate the safety and therapeutic potential of the allogeneic use of equine ucMSCs (e-ucMSCs) in the healing of severe equine leg wounds. The methods employed were the isolation, culture and expansion of e-ucMSCs. Flow cytometry and a PCR assay were used for cell characterization. This study included an immunomodulation assay, a murine pre-clinical trial and the first phase of an equine clinical trial. Our results showed that e-ucMSCs express a functional HLA-G homolog, EQMHCB2. In the immunomodulation assay, the e-ucMSCs inhibited the proliferation of activated equine peripheral blood mononuclear cells (e-PBMCs). In the murine pre-clinical trial, e-ucMSCs reduced healing time by 50%. In the equine clinical trial, the injection of e-ucMSCs into severe leg lesions improved the closure time and quality of the tissues involved, regenerating them without fibrous tissue scar formation. In conclusion, the results of this study suggest that e-ucMSCs can be used allogeneically for wound healing by creating a tolerogenic environment.

Incorporation of Decidual Stromal Cells Derived Exosomes in Sodium Alginate Hydrogel as an Innovative Therapeutic Strategy for Advancing Endometrial Regeneration and Reinstating Fertility.

Intrauterine adhesion (IUA) stands as a prevalent medical condition characterized by endometrial fibrosis and scar tissue formation within the uterine cavity, resulting in infertility and, in severe cases, recurrent miscarriages. Cell therapy, especially with stem cells, offers an alternative to surgery, but concerns about uncontrolled differentiation and tumorigenicity limit its use. Exosomes, more stable and immunogenicity-reduced than parent cells, have emerged as a promising avenue for IUA treatment. In this study, a novel approach has been proposed wherein exosomes originating from decidual stromal cells (DSCs) are encapsulated within sodium alginate hydrogel (SAH) scaffolds to repair endometrial damage and restore fertility in a mouse IUA model. Current results demonstrate that in situ injection of DSC-derived exosomes (DSC-exos)/SAH into the uterine cavity has the capability to induce uterine angiogenesis, initiate mesenchymal-to-epithelial transformation (MET), facilitate collagen fiber remodeling and dissolution, promote endometrial regeneration, enhance endometrial receptivity, and contribute to the recovery of fertility. RNA sequencing and advanced bioinformatics analysis reveal miRNA enrichment in exosomes, potentially supporting endometrial repair. This finding elucidates how DSC-exos/SAH mechanistically fosters collagen ablation, endometrium regeneration, and fertility recovery, holding the potential to introduce a novel IUA treatment and offering invaluable insights into the realm of regenerative medicine.

CICATRICIAL ECTROPION REPAIR DUE TO TRAUMA : A CASE REPORT

Introduction : Cicatricial ectropion is a complication that can occur after trauma. Scar tissue formation causes anterior lamellae shortening (skin and orbicularis muscle), resulting in outward lid margins rotation.
 Case Illustration : A 16 y.o male patient came with complaints of the left upper and lower eyelids folding outwards since 3 months ago after trauma, watery eye. Examination VOD 20/20, VOS 20/50. Scar on the superior and inferior lids, the inferior lid margin is folded out, inferior tarsal conjunctiva is visible, lagophthalmus 4 mm, fissure palpebral vertical (FPV) 12 mm, margin reflex distance (MRD) 1 = 4 mm, MRD2 = 8 mm, fissure palpebral horizontal (FPH) 30 mm, conjunctival injection. Corneal (macular) scars central-peripherally at 3-6 o'clock. Patient was diagnosed with cicatrical ectropion with left eye corneal scar and ectropion repair was performed with full-thickness skin graft from retroarticular. One week and six weeks after surgery, FPV improved to 10 mm, MRD1 = 4, MRD2 = 6 mm, FPH 30 mm, and lagophthalmos 2 mm became 1 mm.
 Discussion : Cicatricial ectropion is usually treated in 3 procedures: release vertical scar traction, horizontal lid tightening, repair anterior lamella can be done with full-thickness skin graft. horizontal lid tightening in this case not carried out because of no laxity.
 Conclusion : Scar traction release and repair anterior lamella with full-thickness skin graft from retroauricular was choice in this case because extensive defect and ectropion grade 3. After surgery anatomical structure of the lids and looks better aesthetically.

The Effects of Bevacizumab in Augmenting Trabeculectomy for Glaucoma : Systematic Review and Meta-Analysis

Introduction & Objectives : Anti-vascular endothelial growth factor (VEGF) agents have been used to slow the healing response and postoperative scar tissue formation. To determine the effectiveness of adding Anti VEGF bevacizumab to the results of trabeculectomy in glaucoma.
 Methods : Searches were conducted in a structured way using keywords across several data sources, including Pubmed, Proquest and Cochrane library. The keywords used for searching were “Bevacizumab”, “Trabeculectomy” and “Glaucoma”. The reviewed articles are Randomized Control Trial in english, conducted on humans in the last 15 years. The review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.
 Results : From a total of 353 articles, there were 6 studies with 362 eyes of 352 patients been evaluated for the effectiveness of bevacizumab addition to trabeculectomy. The primary outcome of all articles was the assessment of Intra Ocular Pressure (IOP). No significant difference in IOP was found between the subconjunctival bevacizumab + Mytomycin-c group and mytomycin-c alone group (MD 0.11 ; 95% CI -0.10 to 0.33), as well as subconjunctival comparison with mytomycin-c (MD 0.11 ; 95% CI -0.29 to 0.50). Similar results were also found in the intracameral and placebo groups (MD 0.08 ; -0.22 to 0.38). However, 3 articles reported significant differences in peripheral vascularity of the bleb both by the Moorfields Bleb Grading System and by the Indiana Bleb Appearance System.
 Conclusion : The addition of bevacizumab to trabeculectomy did not show any benefit in reducing IOP when compared with MMC. But it gives better peripheral vascularity of the bleb.

Novel muscle-derived extracellular matrix hydrogel promotes angiogenesis and neurogenesis in volumetric muscle loss

Volumetric muscle loss (VML) represents a clinical challenge due to the limited regenerative capacity of skeletal muscle. Most often, it results in scar tissue formation and loss of function, which cannot be prevented by current therapies. Decellularized extracellular matrix (DEM) has emerged as a native biomaterial for the enhancement of tissue repair. Here, we report the generation and characterization of hydrogels derived from DEM prepared from WT or thrombospondin (TSP)-2 null muscle tissue. TSP2-null hydrogels, when compared to WT, displayed altered architecture, protein composition, and biomechanical properties and allowed enhanced invasion of C2C12 myocytes and chord formation by endothelial cells. They also displayed enhanced cell invasion, innervation, and angiogenesis following subcutaneous implantation. To evaluate their regenerative capacity, WT or TSP2 null hydrogels were used to treat VML injury to tibialis anterior muscles and the latter induced greater recruitment of repair cells, innervation, and blood vessel formation and reduced inflammation. Taken together, these observations indicate that TSP2-null hydrogels enhance angiogenesis and promote muscle repair in a VML model.

(052) Penile Length Enhancement with Suspensory Ligament Release, Corporal Advancement, and Periosteal Stabilization

Abstract Introduction Penile shortening is a common complaint with multiple etiologies. To date, safe and efficacious options have been limited. Release of the penile suspensory ligament has been described for penile augmentation with a reported increase in penile length, However, a simple release of the suspensory ligament sacrifices the stability of the erect penis. We propose a novel technique of dividing the penile suspensory ligament while simultaneously advancing the corporal bodies and maintaining penile stability with periosteal anchoring of the corpora to the pubic symphysis. Objective We demonstrate a method to increase penile length by releasing the suspensory ligament while simultaneously performing corporal body advancement and anchoring of the corpora to the periosteum of the pubic symphysis. Methods An IRB protocol was submitted to the State University of New York at Buffalo IRB committee. The project was found to be IRB-exempt. A test procedure was performed on a male cadaver. A 3cm transverse infrapubic incision was made one fingerbreadth superior to the dorsal aspect of the penis. Scarpa’s fascia and the fundoform ligament were dissected to expose the suspensory ligament and dorsal phallus. Stretched penile length was measured. The suspensory ligament of the penis was released and the corporal bodies were advanced. A 2-0 Ethibond suture was placed through the periosteum of the inferior aspect of the pubic symphysis and tunica albuginea bilaterally in an intervascular manner. Stretched length was again measured with an increase of approximately four centimeters observed. Results In our cadaveric model, simultaneous penile suspensory ligament with corporal advancement and reattachment resulted in a four-centimeter increase in stretched penile length. Conclusions Simply releasing the suspensory ligament may lead to penile instability, scar tissue formation, and retraction of gained penile length. In this cadaveric model, we demonstrate suspensory ligament release with stabilization of the phallus is viable and may offer a method to increase stretched penile length. Disclosure No.

Role of tear size and tendon degeneration for development of pain in rat models of rotator cuff tear

BackgroundRotator cuff tear (RCT) is a frequent etiology of shoulder pain and disability; however, the triggers for the onset and aggravation of pain remain obscure. In this study, we established novel rat RCT models to examine the impact of tear size and tendon degeneration on pain. MethodsFifty-five adult male Sprague-Dawley rats were allocated into 4 study groups: large tear (L group, n=10); small tear (S group, n=15); small tear with scratching (S+ group n=15); sham surgery (sham group, n=15). Pain-related behaviors were evaluated by weight distribution of forelimbs during a 5-minute free gait using a dynamic weight-bearing apparatus at 2, 4, 6 and 8 weeks. Calcitonin gene-related peptide (CGRP) expressions in ipsilateral dorsal root ganglion (DRG) neurons of C4/5/6 were evaluated at 4 and 8 weeks. The area of scar tissues around the torn tendon, infiltration of inflammatory cells, and severity of tendon degeneration (modified Bonar score) were histologically assessed at 4 and 8 weeks. Additionally, enzyme-linked immunosorbent assay (ELISA) was conducted to evaluate the levels of cyclooxygenase-2 (COX-2) and nerve growth factor (NGF) expression in torn tendons and surrounding tissues at 4 weeks. ResultsThe weight distribution ratio (ipsilateral /contralateral side) was significantly decreased in the L and S+ group compared with its baseline and sham group (P<0.05), but the S group showed no significant difference compared with the Sham. The ratio of CGRP-immunoreactive neurons in the DRGs was significantly higher in the L and S+ groups than in the S and sham groups. The histological assessment indicated that scar tissue formation was more extensive in the L group than in the S and S+ groups. Still, there was no significant difference between the S and S+ groups. The Modified Bonar Score was considerably higher in the S+ group than in the S group. Furthermore, ELISA analysis demonstrated no significant disparity in COX-2 levels between the groups; however, NGF levels were substantially higher in the S+ group than in the S and sham groups. ConclusionThe present study provides compelling evidence that large RCT is strongly associated with heightened pain severity in a rat mode. Nevertheless, even a small tear can significantly aggravate pain when the torn tendon is degenerated. CGRP upregulation driven by peripheral NGF possibly played a pivotal role in the genesis and exacerbation of pain in small RCT.

Modulation of Extracellular Matrix Composition and Chronic Inflammation with Pirfenidone Promotes Scar Reduction in Retinal Wound Repair.

Wound repair in the retina is a complex mechanism, and a deeper understanding of it is necessary for the development of effective treatments to slow down or even prevent degenerative processes leading to photoreceptor loss. In this study, we harnessed a laser-induced retinal degeneration model (532-nm laser photocoagulation with 300 μm spot size, 60 ms duration and 60 mV pulse), enabling a profound molecular elucidation and a comprehensive, prolonged observation of the wound healing sequence in a murine laser-induced degeneration model (C57BL/6J mice, 6-12 weeks) until day 49 post-laser. Our observations included the expression of specific extracellular matrix proteins and myofibroblast activity, along with an analysis of gene expression related to extracellular matrix and adhesion molecules through RNA measurements. Furthermore, the administration of pirfenidone (10 mg/kg via drinking water), an anti-inflammatory and anti-fibrotic compound, was used to modulate scar formation after laser treatment. Our data revealed upregulated collagen expression in late regenerative phases and sustained inflammation in the damaged tissue. Notably, treatment with pirfenidone was found to mitigate scar tissue formation, effectively downregulating collagen production and diminishing the presence of inflammatory markers. However, it did not lead to the regeneration of the photoreceptor layer.

The Use of Honey for Cicatrization and Pain Control of Obstetric Wounds: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Several studies point to antibacterial properties and beneficial effects of honey on scar tissue formation, which is a low-cost and easy-to-use option. This study aimed to compare honey versus a placebo for cicatrization and pain control of obstetric wounds, and determine if one is superior to the other, in terms of efficacy, through a meta-analysis. We searched PubMed, Scopus, Cochrane Central Register of Controlled Trials, and Web of Science. Two independent investigators identified randomized controlled trials (RCTs) comparing honey and a placebo for obstetric wounds. The primary outcomes were wound healing and pain control. Five randomized controlled trials and 353 patients were included, of whom, 177 (50.1%) were treated with honey. Differences were not found in the final wound healing between the honey and placebo groups (MD -0.34; 95% CI -1.13, 0.44; p = 0.39); however, there was a decrease in pain levels in the middle of the treatment (SMD -0.54; 95% CI 0.83 to 0.25, p = 0.03), reduction in the use of pain medication (ORR 0.26; 95% CI 0.08, 0.86; p = 0.03), increase in personal satisfaction in women who underwent the intervention (ORR 0.81; 95% CI 0.65, 0.98), and reduction in complications. According to the study results, honey treatments showed greater efficiency and provided benefits to the patients by accelerating wound healing and decreasing reported pain.

Metformin lotion promotes scarless skin tissue formation through AMPK activation, TGF-β1 inhibition, and reduced myofibroblast numbers.

Scar tissue formation following skin wound healing is a challenging public health problem. Skin regeneration and preventing the formation of scar tissue by currently available commercial products are largely ineffective. This study aimed to test the efficacy of a novel topical metformin lotion (ML) in inhibiting scar tissue formation during skin wound healing in rats and to determine the mechanisms of action involved. A 6% ML was prepared in our laboratory. A skin wound healing model in rats was used. The wounded rats were divided into two groups and treated daily for 10 days as follows: Group 1 received a daily application of 50 mg of control lotion, or 0% ML (totaling 100 mg of lotion per rat), and Group 2 received a daily application of 50 mg of 6% ML (totaling 100 mg of 6% ML per rat). Blood samples from the heart of each rat were analyzed for inflammatory markers, HMGB1 and IL-1β, using ELISA, and immunological and histological analyses were performed on skin tissue sections. ML decreased levels of inflammatory markers HMGB1 and IL-1β in the serum of rats and inhibited the release of HMGB1 from cell nuclei into the skin tissue matrix. Additionally, ML demonstrated anti-fibrotic properties by enhancing AMPK activity, decreasing the expression of TGF-β1, reducing the number of myofibroblasts, decreasing the production of collagen III, and increasing the expression of collagen I. ML promotes the regeneration of high-quality skin during wound healing by reducing scar tissue formation. This effect is mediated through the activation of AMPK, inhibition of TGF-β1, and a decrease in the number of myofibroblasts.

Combined use of biomaterials and revascularisation in autoplasty of ulnar nerve

Surgical treatment of peripheral nerve injuries is effective in only 50% of cases. This is primarily due to the significant extent of the diastasis between the fragments of the damaged nerve, in which autoplasty has to be performed. The drawbacks of this technique are the formation of scar tissue, possible necrotisation of the autograft, mismatch of the donor and recipient nerve diameters. In order to overcome these drawbacks and improve the efficiency of surgical intervention, the study presents a clinical case of successful multifascicular ulnar nerve autoplasty with the use of domestic biodegradable biomaterials SpheroGel and ElastoPob, revascularization of the autograft with a connective tissue flap on a vascular pedicle. A persistent regression of local pain syndrome was observed in the early postoperative period. The effectiveness of the performed surgical intervention was confirmed by ultrasound examination: there was no evidence of neuroma in the area of the operation, regeneration of nerve bundles was noted at the site of stitching. Positive dynamics was observed in the results of VAS, DN4, DASH questionnaires.

Inhibition of the ITGB1 gene attenuates crystalline silica-induced pulmonary fibrosis via epithelial-mesenchymal transformation.

Silicosis is a systemic disease caused by long-term exposure to high concentrations of free silica dust particles in the workplace. It is characterized by a persistent inflammatory response, fibroblast proliferation, and excessive collagen deposition, leading to pulmonary interstitial fibrosis. Epithelial interstitial transformation (EMT) can cause epithelial cells to lose their tight junctions, cell polarity, and epithelial properties, thereby enhancing the properties of interstitial cells, which can lead to the progression of fibrosis and the formation of scar tissue. Integrin 1 (ITGB1) is considered an important factor for promoting EMT and tumor invasion in a variety of tumors and also plays an important role in the progression of fibrotic diseases. Therefore, ITGB1 can be used as a potential target for the treatment of silicosis. In this study, we found that silica exposure induced epithelial-mesenchymal transformation in rats and that the expression of integrin ITGB1 was elevated along with the EMT. We used CRISPR/Cas9 technology to construct integrin ITGB1 knockdown cell lines for in vitro experiments. We compared the expression of the EMT key proteins E-cadherin and vimentin in the ITGB1 knockdown cells and wild-type cells simultaneously stimulated by silica and detected the aggregation point distribution of E-cadherin and vimentin in the cells using laser confocal microscopy. Our results showed that ITGB1 knockout inhibited the ITGB1/ILK/Snail signaling pathway and attenuated the EMT occurrence compared to control cells. These results suggested that ITGB1 is associated with silica-induced EMT and may be a potential target for the treatment of silicosis.

Development of a tannic acid- and silicate ion-functionalized PVA-starch composite hydrogel for in situ skeletal muscle repairing.

The repair capacity of skeletal muscle is severely diminished in massive skeletal muscle injuries accompanied by inflammation, resulting in muscle function loss and scar tissue formation. In the current work, we developed a tannic acid (TA)- and silicate ion-functionalized tissue adhesive poly(vinyl alcohol) (PVA)-starch composite hydrogel, referred to as PSTS (PVA-starch-TA-SiO32-). It was formed based on the hydrogen bonding of TA to organic polymers, as well as silicate-TA ligand interaction. PSTS could be gelatinized in minutes at room temperature with crosslinked network formation, making it applicable for injection. Further investigations revealed that PSTS had skeletal muscle-comparable conductivity and modulus to act as a temporary platform for muscle repairing. Moreover, PSTS could release TA and silicate ions in situ to inhibit bacterial growth, induce vascularization, and reduce oxidation, paving the way to the possibility of creating a favorable microenvironment for skeletal muscle regeneration and tissue fibrosis control. The in vivo model confirmed that PSTS could enhance muscle fiber regeneration and myotube formation, as well as reduce infection and inflammation risk. These findings thereby implied the great potential of PSTS in the treatment of formidable skeletal muscle injuries.

From Time to Timer in Wound Healing Through the Regeneration.

Hard-to-heal wounds are an important public health issue worldwide, with a significant impact on the quality of life of patients. It is estimated that approximately 1-2% of the global population suffers from difficult wounds, which can be caused by a variety of factors such as trauma, infections, chronic diseases like diabetes or obesity, or poor health conditions. Hard-to-heal wounds are often characterized by a slow and complicated healing process, which can lead to serious complications such as infections, pressure ulcers, scar tissue formation, and even amputations. These complications can have a significant impact on the mobility, autonomy, and quality of life of patients, leading to an increase in healthcare and social costs associated with wound care. The preparation of the wound bed is a key concept in the management of hard-to-heal wounds, with the aim of promoting an optimal environment for healing. The TIME (Tissue, Infection/Inflammation, Moisture, Edge) model is a systematic approach used to assess and manage wounds in a targeted and personalized way. The concept of TIMER, expanding the TIME model, further focuses on regenerative processes, paying particular attention to promoting tissue regeneration and wound healing in a more effective and comprehensive way. The new element introduced in the TIMER model is "Regeneration", which highlights the importance of activating and supporting tissue regeneration processes to promote complete and lasting wound healing. Regenerative therapies can include a wide range of approaches, including cellular therapies, growth factors, bioactive biomaterials, stem cell therapies, and growth factor therapies. These therapies aim to promote the formation of new healthy tissues, reduce inflammation, improve vascularization, and stimulate cellular proliferation to accelerate wound closure and prevent complications. Thanks to continuous progress in research and development of regenerative therapies, more and more patients suffering from difficult wounds can benefit from innovative and promising solutions to promote faster and more effective healing, improve quality of life, and reduce the risk of long-term complications.

Efficacy of collagen conduit wrapping with collagen fibers on nerve regeneration in sciatic nerve injury with partial transection: An experimental study in the rat model.

Peripheral nerve injuries (PNIs) include complete and partial transection, crushing, and chronic compression injuries. Hollow absorbable conduits are used to treat complete transection with short defects, while wrapping the injured part with an absorbent material promotes nerve recovery by inhibiting inflammatory cell infiltration and scar tissue formation in crush injuries. For treatment of partially transected nerve injuries (PTNIs), such as injection-related iatrogenic PNI, whether wrapping the entire nerve, including the injury site, or bridging the transected fascicle with an artificial nerve conduit (ANC) is beneficial remains to be verified. The purpose of this study was to investigate whether wrapping the injured nerve and placing collagen fibers as scaffolds at the nerve defect site contribute to neural recovery in PTNI. A unilateral 5-mm partial nerve defect was created at the mid-thigh level in a rat sciatic nerve injury model. Fifty-four Sprague-Dawley (SD) rats (150-250 g) were divided into three groups (n = 9 each): group 1, collagen fibers were placed in the nerve defect and the sciatic nerve was wrapped with collagen conduit; group 2, the sciatic nerve was wrapped by collagen conduit without collagen fibers; and group 3, nerve defect was reconstructed with collagen-filled conduit. Nerve regeneration was evaluated by analyses of gait, electrophysiology, wet muscle weight, and axon numbers with immunohistochemistry at 12 and 24 weeks. Dorsiflexion angles among all groups improved significantly from 12 to 24 weeks postoperatively. At 24 weeks postoperatively, compound muscle action potential amplitudes (CMAPs) of tibialis anterior were 5.26 ± 4.64, 1.31 ± 1.17, and 0.14 ± 0.24 mV (p < .05), CMAPs of gastrocnemius were 21.3 ± 5.98, 15.4 ± 5.46, and 13.11 ± 3.91 mV in groups 1, 2, and 3, respectively; and the value of group 1 was significantly higher than that of group 3 (p < .05). Axon numbers were 2194 ± 629; 1106 ± 645; and 805 ± 907 in groups 1, 2, and 3, respectively (p < .05). For PTNI reconstruction, artificial nerve wrap (ANW) was superior to ANC. Providing collagen scaffold at the nerve defect site enhanced nerve recovery during reconstruction with ANW.

Potential Application of Modified mRNA in Cardiac Regeneration.

Heart failure remains the leading cause of human death worldwide. After a heart attack, the formation of scar tissue due to the massive death of cardiomyocytes leads to heart failure and sudden death in most cases. In addition, the regenerative ability of the adult heart is limited after injury, partly due to cell-cycle arrest in cardiomyocytes. In the current post-COVID-19 era, urgently authorized modified mRNA (modRNA) vaccines have been widely used to prevent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Therefore, modRNA-based protein replacement may act as an alternative strategy for improving heart disease. It is a safe, effective, transient, low-immunogenic, and integration-free strategy for in vivo protein expression, in addition to recombinant protein and stem-cell regenerative therapies. In this review, we provide a summary of various cardiac factors that have been utilized with the modRNA method to enhance cardiovascular regeneration, cardiomyocyte proliferation, fibrosis inhibition, and apoptosis inhibition. We further discuss other cardiac factors, modRNA delivery methods, and injection methods using the modRNA approach to explore their application potential in heart disease. Factors for promoting cardiomyocyte proliferation such as a cocktail of three genes comprising FoxM1, Id1, and Jnk3-shRNA (FIJs), gp130, and melatonin have potential to be applied in the modRNA approach. We also discuss the current challenges with respect to modRNA-based cardiac regenerative medicine that need to be overcome to apply this approach to heart disease. This review provides a short description for investigators interested in the development of alternative cardiac regenerative medicines using the modRNA platform.

Chronic Achilles Tendon Avulsion Repair: Central Third Fascia Slide Technique with Flexor Hallucis Longus Transfer.

Chronic Achilles Tendon Avulsion Repair: Central Third Fascia Slide Technique with Flexor Hallucis Longus Transfer.

Minimally Invasive Chevron Akin Osteotomy for Hallux Valgus Correction.

Minimally Invasive Chevron Akin Osteotomy for Hallux Valgus Correction.