Free Fibular Osteocutaneous Flap Combined With Simultaneous Tendon Reconstruction for Midfoot Restoration After Myoepithelial Carcinoma Resection.

ABSTRACT: Myoepithelial carcinomas of soft tissue are rare, and most are malignant. The optimal treatment is surgical excision. The arches of the foot are a composite structure responsible for weight bearing and pressure distribution, so it is a vast challenge in reconstruction. We report a case of reconstruction of the midfoot with a free fibular bone flap and tendon graft. We review the literature to compare various options in foot reconstructions and sort out the outcomes of different bone flaps. The free fibula osteocutaneous flap is the superior choice for midfoot reconstruction owing to its sufficient length, strength, flexible skin paddles, easy-to-withstand osteotomy, and simultaneous tendon graft harvesting.

Comparative Efficacy of Drug Interventions for Keloids: A Network Meta-analysis.

BACKGROUND: Keloids are common benign skin lesions originating from a disorganized fibroproliferative collagen response; these lesions often lead to both physical and psychological problems. The optimal treatment for keloids is yet to be standardized. Intralesional injection, which is simple and nontraumatic, is one of the most commonly used treatment modalities for these lesions. In this study, we compared 5 different drugs (intralesional injections) for the treatment of keloids in terms of efficacy. METHODS: We systemically searched relevant studies on PubMed, EMBASE, and Cochrane Library. Randomized clinical trials on the safety and efficacy of triamcinolone acetonide (TAC), 5-fluorouracil (5-FU), botulinum toxin A (BTA), verapamil, and bleomycin were included in this study. RESULTS: This network meta-analysis included a total of 1114 patients from 20 randomized controlled trials. Botulinum toxin A alone and TAC plus 5-FU exhibited significantly better efficacy than did 5-FU, TAC, and verapamil. No significant difference in efficacy between BTA alone and TAC combined with 5-FU was observed. No significant differences were noted in the adverse event rate between BTA, TAC plus 5-FU, 5-FU, and TAC. Furthermore, we performed surface under the cumulative ranking curve analyses to predict the rank of each intervention (by efficacy and adverse event rate). The predicted ranking by efficacy was as follows: TAC plus 5-FU, BTA, bleomycin, TAC, 5-FU, and verapamil; the predicted ranking by adverse events was as follows: TAC, 5-FU, TAC plus 5-FU, and BTA. Funnel plot analysis revealed no publication bias. CONCLUSIONS: Botulinum toxin A and TAC plus 5-FU appear to have outstanding therapeutic efficacy for keloids. The rate of adverse events was similar among BTA, TAC, 5-FU, and TAC plus 5-FU. Nonetheless, additional reviews of rigorous, large-scale randomized controlled trials are warranted for further validation of our findings.

Rehabilitation Program for Postlaryngectomy Patients Following Ileocolon Flap Transfer for Voice Reconstruction: An Essential Part of Success.

BACKGROUND: Speech restoration is important for communication and social activities after pharyngolaryngectomy in head and neck cancer or corrosive injury. Several techniques of voice restoration have been developed to improve life quality. The aim of this paper was to focus on the microsurgical transfer of ileocolon flap and outcome of further voice rehabilitation. PATIENTS AND METHODS: From 2010 to 2022, 69 patients had ileocolon flap at our hospital with postoperative speech training and regular follow-up for over 1 year. The patients received deglutition training first, followed by voice rehabilitation. Voice outcomes were evaluated at an interval of 3 months and finally at 12 months of voice training rehabilitation. Among other examinations, the speech function was evaluated using a 4-point Likert scale and senior surgeon (H-c.C.) scoring system. RESULTS: The results showed that speech function reached 13.1% of excellent voice, 65.1% of good voice, 13.1% of fair result, and 8.7% of poor result by Likert scales. Meanwhile, the senior surgeon (H-c.C.) score showed 17.4% of excellent, 63.8% of moderate, and 18.8% of poor results. About voice laboratory results, maximal phonation time was 11.0 seconds, and the average number counted in one breath was 15. Loudness and frequency showed 56.0 dB and 105.0 Hz, respectively. CONCLUSION: The study showed that after voice reconstruction with ileocolon flap followed by the voice rehabilitation program, the patients would have a better understanding of the altered anatomical structures and practice in a more efficient way. Adequate recommendation by the therapists to plastic surgeons for revision surgeries optimized voice function of the patients.

The Synergistic Effect of Electrical Stimulation and Dermal Fibroblast Cells-Laden 3D Conductive Hydrogel for Full-Thickness Wound Healing.

Clinically, most patients with poor wound healing suffer from generalized skin damage, usually accompanied by other complications, so developing therapeutic strategies for difficult wound healing has remained extremely challenging until now. Current studies have indicated that electrical stimulation (ES) to cutaneous lesions enhances skin regeneration by activating intracellular signaling cascades and secreting skin regeneration-related cytokine. In this study, we designed different concentrations of graphene in gelatin-methacrylate (GelMa) to form the conductive composite commonly used in wound healing because of its efficiency compared to other conductive thermo-elastic materials. The results demonstrated the successful addition of graphene to GelMa while retaining the original physicochemical properties of the GelMa bioink. In addition, the incorporation of graphene increased the interactions between these two biomaterials, leading to an increase in mechanical properties, improvement in the swelling ratio, and the regulation of degradation characteristics of the biocomposite scaffolds. Moreover, the scaffolds exhibited excellent electrical conductivity, increasing proliferation and wound healing-related growth factor secretion from human dermal fibroblasts. Overall, the HDF-laden 3D electroconductive GelMa/graphene-based hydrogels developed in this study are ideal biomaterials for skin regeneration applications in the future.

Clinical T4b Squamous Cell Carcinoma Resection With Hemimandibulectomy and Temporomandibular Joint Reconstruction With Bridging Plate and Modified Dautrey Procedure.

ABSTRACT: Clinical T4b oral squamous cell carcinoma is traditionally considered nonoperable. We present a case of right mandibular squamous cell carcinoma (PT4bN0M0, stage IVB). The tumor had extended to the right mandibular condylar head and masticatory space. The patient received right modified radical neck dissection and radical operation with hemimandibulectomy to remove the right mandibular condyle. Then, we reconstructed the resected portion with an anterior lateral thigh free flap and bridging plate, which was bent to form an artificial condyle and fixed using the modified Dautrey procedure. The patient had stable postoperative occlusion and normal hinge movement of the temporomandibular joint. After postoperative concurrent chemotherapy and radiotherapy, the patient is under regular out patient department follow-up with satisfactory jaw function and oral intake.

Galangin Reverses H2O2-Induced Dermal Fibroblast Senescence via SIRT1-PGC-1α/Nrf2 Signaling.

UV radiation and H2O2 are the primary factors that cause skin aging. Both trigger oxidative stress and cellular aging. It has been reported that deacetylase silent information regulator 1 (SIRT1), a longevity gene, enhances activation of NF-E2-related factor-2 (Nrf2), as well as its downstream key antioxidant gene hemeoxygenase-1 (HO-1), to protect cells against oxidative damage by deacetylating the transcription coactivator PPARγ coactivator-1α (PGC-1α). Galangin, a flavonoid, possesses anti-oxidative and anti-inflammatory potential. In the present study, we applied Ultraviolet B/H2O2-induced human dermal fibroblast damage as an in vitro model and UVB-induced photoaging of C57BL/6J nude mice as an in vivo model to investigate the underlying dermo-protective mechanisms of galangin. Our results indicated that galangin treatment attenuates H2O2/UVB-induced cell viability reduction, dermal aging, and SIRT1/PGC-1α/Nrf2 signaling activation. Furthermore, galangin treatment enhanced Nrf2 activation and nuclear accumulation, in addition to inhibiting Nrf2 degradation. Interestingly, upregulation of antioxidant response element luciferase activity following galangin treatment indicated the transcriptional activation of Nrf2. However, knockdown of SIRT1, PGC-1α, or Nrf2 by siRNA reversed the antioxidant and anti-aging effects of galangin. In vivo evidence further showed that galangin treatment, at doses of 12 and 24 mg/kg on the dorsal skin cells of nude mice resulted in considerably reduced UVB-induced epidermal hyperplasia and skin senescence, and promoted SIRT1/PGC-1α/Nrf2 signaling. Furthermore, enhanced nuclear localization of Nrf2 was observed in galangin-treated mice following UVB irradiation. In conclusion, our data indicated that galangin exerts anti-photoaging and antioxidant effects by promoting SIRT1/PGC-1α/Nrf2 signaling. Therefore, galangin is a potentially promising agent for cosmetic skin care products against UV-induced skin aging.

Drainage outflow restriction as a parameter associated with cortical venous reflux in craniofacial arteriovenous malformations with cavernous sinus drainage.

PURPOSE: Craniofacial arteriovenous malformations (CF-AVMs) are locally aggressive extracranial lesions. When CF-AVMs involve cavernous sinus (CS) as their draining vein, they represent a special subgroup which may interfere intracranial venous system. In this study, we aimed to analyze the venous drainage patterns of CF-AVMs with CS drainage and to demonstrate how it affected our treatment strategy. METHODS: Cases of CF-AVMs associated with CS drainage were collected from a prospectively collected database of patients with CF-AVMs who underwent endovascular treatment from September 2016 to March 2018. Clinical data and angioarchitectural findings were analyzed. Factors associated with the presence of venous reflux (cortical venous reflux (CVR) or dural sinus reflux (DSR)) were analyzed. RESULTS: Fifteen CF-AVM patients associated with CS drainage were analyzed. Three cases of venous reflux from the CS were identified (CVR, 2; DSR, 1). Lesions with unilateral venous drainage, ≤ 2 draining veins, and the absence of antegrade CS outflow were more likely to develop venous reflux from the CS. We successfully performed additional trans-venous coil embolization of the superior ophthalmic vein in two patients with malformations associated with venous reflux to close this venous connection to the CS. CONCLUSION: CF-AVMs associated with CS drainage confer an increased risk of CVR and DSR, especially in cases where the drainage outflow is restricted. Identification of this venous angioarchitecture is essential in the evaluation and treatment planning of CF-AVMs.

Redistribution of Cav2.1 channels and calcium ions in nerve terminals following end-to-side neurorrhaphy: ionic imaging analysis by TOF-SIMS.

The P/Q-type voltage-dependent calcium channel (Cav2.1) in the presynaptic membranes of motor nerve terminals plays an important role in regulating Ca2+ transport, resulting in transmitter release within the nervous system. The recovery of Ca2+-dependent signal transduction on motor end plates (MEPs) and innervated muscle may directly reflect nerve regeneration following peripheral nerve injury. Although the functional significance of calcium channels and the levels of Ca2+ signalling in nerve regeneration are well documented, little is known about calcium channel expression and its relation with the dynamic Ca2+ ion distribution at regenerating MEPs. In the present study, end-to-side neurorrhaphy (ESN) was performed as an in vivo model of peripheral nerve injury. The distribution of Ca2+ at regenerating MEPs following ESN was first detected by time-of-flight secondary ion mass spectrometry, and the specific localization and expression of Cav2.1 channels were examined by confocal microscopy and western blotting. Compared with other fundamental ions, such as Na+ and K+, dramatic changes in the Ca2+ distribution were detected along with the progression of MEP regeneration. The re-establishment of Ca2+ distribution and intensity were correlated with the functional recovery of muscle in ESN rats. Furthermore, the re-clustering of Cav2.1 channels after ESN at the nerve terminals corresponded with changes in the Ca2+ distribution. These results indicated that renewal of the Cav2.1 distribution within the presynaptic nerve terminals may be necessary for initiating a proper Ca2+ influx and shortening the latency of muscle contraction during nerve regeneration.

Classification of the Conjoined Latissimus Dorsi-Groin Flap and Indications for the Four Types of the Flap.

SUMMARY: The conjoined latissimus dorsi-groin flap is a versatile flap that not only can serve as an osteocutaneous flap to provide large soft tissue and bone for reconstruction of extensive defects but also can offer functioning muscle transfer and lymph node transfer for prevention of lymphedema after wide excision of tumors or major trauma. Over the past 24 years, the authors have classified the conjoined latissimus dorsi-groin flap into four categories. They propose precautions for application of the conjoined flaps.

Tracheal Replacement Techniques and Associated Mortality: A Systematic Review.

OBJECTIVE: Tracheal replacement is a crucial operation to enhance the quality of life for patients with extensive tracheal lesions. The most suitable surgical techniques for different clinical conditions remain a topic of debate. Through a reviewing of the relevant literature, this study investigated the association between surgical techniques and mortality rate. DATA SOURCES: Studies were collected from PubMed, Embase, the Web of Science, the Cochrane Center Register of Controlled Trials, and ClinicalTrials.gov. METHODS: This systematic review encompassed literature from the inception of each database to May 10, 2023, focusing on tracheal replacement for patients who underwent circumferential resection of the trachea or partial resection with preservation of the posterior membranous wall. Non-human and non-clinical studies were excluded. RESULTS: About 31 studies were included in the assessment comprising a combination of case reports and case series, and 118 patients underwent tracheal replacement through four underlying methodologies, including tracheal allotransplantation, autologous tissue reconstruction, bioprosthetic reconstruction, or tissue engineering surgery. Each modality exhibits unique advantages and disadvantages, leading to variable outcomes in clinical application. CONCLUSION: Tracheal replacement is challenging due to the absence of an ideal substitution or graft material. Despite limited clinical successes observed across various modalities, we believe autologous tissue reconstruction for tracheal replacement has the advantage of broadest indications, low rejection rate, and avoidance of immunosuppressive agents. Future research should focus on achieving tracheal replacement that preserves mucociliary clearance, lateral rigidity, and longitudinal flexibility. LEVEL OF EVIDENCE: NA Laryngoscope, 134:1517-1522, 2024.

Prognostic Factors of Marjolin Ulcers: A Meta-Analysis and Systematic Review Assisted by Machine Learning Techniques.

BACKGROUND: Marjolin ulcers (MUs) are malignant tumors arising from previously injured skin, including burn wounds, scars, chronic ulcers, and other chronic nonhealing inflammatory conditions. They have a potentially long latent period. The authors aimed to establish the prognostic factors for recurrence, metastasis, and disease-specific death related to MU. METHODS: The authors performed a comprehensive search of PubMed, Embase, and the Cochrane Library. After assessing the methodologic quality of case series, they performed a meta-analysis and systematic review. Furthermore, the authors used machine learning to predict patient survival time. RESULTS: MUs on the upper limbs, head, and neck had a higher risk of recurrence. Contrastingly, lower grade lesions, absence of lymph node metastasis, and a tumor diameter of less than 10 cm were associated with lower recurrence risk. The risks were unrelated to age and latent period. In addition, patients without lymph node metastasis had a lower risk of developing distant metastasis. Furthermore, the risk of disease-specific death was lower in patients with a lower tumor grade, absent lymph node metastasis, small tumor diameter (<10 cm), and tumors located in regions other than the head and neck. Correlation analysis showed that the age at initial injury was negatively correlated with the latent period of MU. CONCLUSIONS: The authors found that tumor grade, tumor site, lymph node status, and tumor size are important predictors of a worse prognosis. To integrate these predictors, the authors created an equation to predict the survival time for individual patients by means of machine learning processes. Moreover, the authors found that MU developed more quickly in older individuals with injuries.

Transaxillary Capsulorrhaphy with Reimplantation to Correct Bottoming-Out Deformity in Breast Mycobacterial Periprosthetic Infection: A Case Report with Literature Review.

Augmentation mammoplasty is one of the most popular cosmetic surgeries, but there is a high reoperation rate (29.7%) commonly due to capsular contracture, implant malpositioning, infection, and unsatisfactory size. Although infection only accounts for 2% of cases, its management is very challenging, especially with nontuberculous mycobacteria (NTM) infection. Breast prosthetic NTM infection is a rare but is a disastrous condition with an incidence of approximately 0.013%. Immediate salvage reimplantation is usually not suggested, and most studies recommend a gap of 3 to 6 months after combination antibiotics therapy before reimplantation. However, delayed reimplantation often leads to great psychological stress and struggle between the doctor and patient. We present the case report of successful reimplantation in treating prosthetic NTM infections in a 28-year-old female. We discuss a novel technique "transaxillary capsulorrhaphy" to correct the bottoming-out deformity. One year after the combination of antibiotics and surgery, the follow-up computed tomography scan showed complete remission of NTM without recurrence. We discuss the surgical technique in detail. The 1-year follow-up assessment (photos and dynamic video) revealed good cosmesis and reliable correction using the new technique. This report is the first formal description and discussion of one-stage reimplantation following NTM infections. Transaxillary capsulorrhaphy allows for a successful salvage operation when an implant is displaced. This approach provides highly favorable result in eastern women undergoing revision augmentation mammoplasty. This study reflects level of evidence V, considering opinions of respected authorities based on clinical experience, descriptive studies, or reports of expert committees.

Effects of the individual three-dimensional printed craniofacial bones with a quick response code on the skull spatial knowledge of undergraduate medical students.

Understanding the three-dimensional (3D) structure of the human skull is imperative for medical courses. However, medical students are overwhelmed by the spatial complexity of the skull. Separated polyvinyl chloride (PVC) bone models have advantages as learning tools, but they are fragile and expensive. This study aimed to reconstruct 3D-printed skull bone models (3D-PSBs) using polylactic acid (PLA) with anatomical characteristics for spatial recognition of the skull. Student responses to 3D-PSB application were investigated through a questionnaire and tests to understand the requirement of these models as a learning tool. The students were randomly divided into 3D-PSB (n = 63) and skull (n = 67) groups to analyze pre- and post-test scores. Their knowledge was improved, with the gain scores of the 3D-PSB group (50.0 ± 3.0) higher than that of the skull group (37.3 ± 5.2). Most students agreed that using 3D-PSBs with quick response codes could improve immediate feedback on teaching (88%; 4.41 ± 0.75), while 85.9% of the students agreed that individual 3D-PSBs clarified the structures hidden within the skull (4.41 ± 0.75). The ball drop test revealed that the mechanical strength of the cement/PLA model was significantly greater than that of the cement or PLA model. The prices of the PVC, cement, and cement/PLA models were 234, 1.9, and 10 times higher than that of the 3D-PSB model, respectively. These findings imply that low-cost 3D-PSB models could revolutionize skull anatomical education by incorporating digital technologies like the QR system into the anatomical teaching repertoire.

Truncation of GalNAc-type O-glycans Suppresses CD44-mediated Osteoclastogenesis and Bone Metastasis in Breast Cancer.

The glycoprotein CD44 is a key regulator of malignant behaviors in breast cancer cells. To date, hyaluronic acid (HA)-CD44 signaling pathway has been widely documented in the context of metastatic bone diseases. Core 1 ß1,3-galactosyltransferase (C1GALT1) is a critical enzyme responsible for the elongation of O-glycosylation. Aberrant O-glycans is recognized as a hallmark in cancers. However, the effects of C1GALT1 on CD44 signaling and bone metastasis remain unclear. In this study, IHC analysis indicated that C1GALT1 expression positively correlates with CD44 in breast cancer. Silencing C1GALT1 accumulates the Tn antigen on CD44, which decreases CD44 levels and osteoclastogenic signaling. Mutations in the O-glycosites on the stem region of CD44 impair its surface localization as well as suppress cell-HA adhesion and osteoclastogenic effects of breast cancer cells. Furthermore, in vivo experiments demonstrated the inhibitory effect of silencing C1GALT1 on breast cancer bone metastasis and bone loss. In conclusion, our study highlights the importance of O-glycans in promoting CD44-mediated tumorigenic signals and indicates a novel function of C1GALT1 in driving breast cancer bone metastasis. IMPLICATIONS: Truncation of GalNAc-type O-glycans by silencing C1GALT1 suppresses CD44-mediated osteoclastogenesis and bone metastasis in breast cancer. Targeting the O-glycans on CD44 may serve as a potential therapeutic target for blocking cancer bone metastasis.

Successful treatment of Kasabach-Merritt phenomenon with intralesional corticosteroid injections: a case series.

Kasabach-Merritt phenomenon (KMP) is a rare and life-threatening disease of vascular tumor combined with severe consumptive coagulopathy. Currently, there is no established effective treatment of KMP. In this case series, from 2006 to 2008, we treated 6 pediatric patients with newly diagnosed KMP using intralesional corticosteroid injections. The severity and progression of the disease were closely monitored with clinical photographs, blood sampling, and tissue biopsies. The 6 pediatric patients (5 females and 1 male) showed tumor regression after treatments. All coagulopathies were corrected. The average duration of treatment was 3.8 months. Complete tumor regression was observed at approximately 3 years. Treatment was complicated in 1 patient with transient growth retardation. Treatment based on intralesional corticosteroid injections is effective for pediatric patients with KMP. Treatment-associated complications seemed to be reversible and acceptable by severity level.

The Synergistic Effect of Cyclic Tensile Force and Periodontal Ligament Cell-Laden Calcium Silicate/Gelatin Methacrylate Auxetic Hydrogel Scaffolds for Bone Regeneration.

The development of 3D printing technologies has allowed us to fabricate complex novel scaffolds for bone regeneration. In this study, we reported the incorporation of different concentrations of calcium silicate (CS) powder into fish gelatin methacrylate (FGelMa) for the fabrication of CS/FGelMa auxetic bio-scaffolds using 3D printing technology. Our results showed that CS could be successfully incorporated into FGelMa without influencing the original structural components of FGelMa. Furthermore, it conveyed that CS modifications both the mechanical properties and degradation rates of the scaffolds were improved in accordance with the concentrations of CS upon modifications of CS. In addition, the presence of CS enhanced the adhesion and proliferation of human periodontal ligament cells (hPDLs) cultured in the scaffold. Further osteogenic evaluation also confirmed that CS was able to enhance the osteogenic capabilities via activation of downstream intracellular factors such as pFAK/FAK and pERK/ERK. More interestingly, it was noted that the application of extrinsic biomechanical stimulation to the auxetic scaffolds further enhanced the proliferation and differentiation of hPDLs cells and secretion of osteogenic-related markers when compared to CS/FGelMa hydrogels without tensile stimulation. This prompted us to explore the related mechanism behind this interesting phenomenon. Subsequent studies showed that biomechanical stimulation works via YAP, which is a biomechanical cue. Taken together, our results showed that novel auxetic scaffolds could be fabricated by combining different aspects of science and technology, in order to improve the future chances of clinical applications for bone regeneration.

The 3D printed conductive grooved topography hydrogel combined with electrical stimulation for synergistically enhancing wound healing of dermal fibroblast cells.

Patients with extensive cutaneous damage resulting from poor wound healing often have other comorbidities such as diabetes that may lead to impaired skin functions and scar formation. Many recent studies have shown that the application of electrical stimulation (ES) to cutaneous lesions significantly improves skin regeneration via activation of AKT intracellular signaling cascades and secretion of regeneration-related growth factors. In this study, we fabricated varying concentrations of gelatin-methacrylate (GelMa) hydrogels with poly(3,4-ethylenedioxythiophene) (PEDOT): polystyrene sulfonate (PSS), which is a conductive material commonly used in tissue engineering due to its efficiency among conductive thermo-elastic materials. The results showed successful modification of PEDOT:PSS with GelMa while retaining the original structural characteristics of the GelMa hydrogels. In addition, the incorporation of PEDOT:PSS increased the interactions between both the materials, thus leading to enhanced mechanical strength, improved swelling ratio, and decreased hydrophilicity of the scaffolds. Our GelMa/PEDOT:PSS scaffolds were designed to have micro-grooves on the surfaces of the scaffolds for the purpose of directional guiding. In addition, our scaffolds were shown to have excellent electrical conductivity, thus leading to enhanced cellular proliferation and directional migration and orientation of human dermal fibroblasts. In vivo studies revealed that the GelMa/PEDOT:PSS scaffolds with electrical stimulation were able to induce full skin thickness regeneration, as seen from the various stainings. These results indicate the potential of GelMa/PEDOT:PSS as an electro-conductive biomaterial for future skin regeneration applications.

Additive Manufacturing of Caffeic Acid-Inspired Mineral Trioxide Aggregate/Poly-ε-Caprolactone Scaffold for Regulating Vascular Induction and Osteogenic Regeneration of Dental Pulp Stem Cells.

Mineral trioxide aggregate (MTA) is a common biomaterial used in endodontics regeneration due to its antibacterial properties, good biocompatibility and high bioactivity. Surface modification technology allows us to endow biomaterials with the necessary biological targets for activation of specific downstream functions such as promoting angiogenesis and osteogenesis. In this study, we used caffeic acid (CA)-coated MTA/polycaprolactone (PCL) composites and fabricated 3D scaffolds to evaluate the influence on the physicochemical and biological aspects of CA-coated MTA scaffolds. As seen from the results, modification of CA does not change the original structural characteristics of MTA, thus allowing us to retain the properties of MTA. CA-coated MTA scaffolds were shown to have 25% to 55% higher results than bare scaffold. In addition, CA-coated MTA scaffolds were able to significantly adsorb more vascular endothelial growth factors (p < 0.05) secreted from human dental pulp stem cells (hDPSCs). More importantly, CA-coated MTA scaffolds not only promoted the adhesion and proliferation behaviors of hDPSCs, but also enhanced angiogenesis and osteogenesis. Finally, CA-coated MTA scaffolds led to enhanced subsequent in vivo bone regeneration of the femur of rabbits, which was confirmed using micro-computed tomography and histological staining. Taken together, CA can be used as a potently functional bioactive coating for various scaffolds in bone tissue engineering and other biomedical applications in the future.

Protective effects of galangin against H2O2/UVB-induced dermal fibroblast collagen degradation via hsa-microRNA-4535-mediated TGFß/Smad signaling.

This study aimed to investigate the mechanism underlying the protective effects of galangin against H2O2/UVB-induced damage using in vitro and in vivo models of photodamage. Moreover, we identified the involvement of miRNA regulation in this process. The H2O2/UVB-treated HS68 human dermal fibroblasts and UVB-induced C57BL/6J nude mice were used as in vitro and in vivo models of photodamage. The results showed that galangin treatment alleviated H2O2/UVB-induced reduction in cell viability, TGFß/Smad signaling impairment, and dermal aging. Based on the results of microRNA array analyses and database searches, hsa-miR-4535 was identified as a potential candidate miRNA that targets Smad4. In vitro, galangin treatment activated Smad2/3/4 complex and inhibited hsa-miR-4535 expression in H2O2/UVB-exposed cells. In vivo, topical application of low (12 mg/kg) and high doses (24 mg/kg) of galangin to the dorsal skin of C57BL/6J nude mice significantly alleviated UVB-induced skin photodamage by promoting TGFß/Smad collagen synthesis signaling, reducing epidermal hyperplasia, wrinkle formation, and skin senescence, as well as inhibiting hsa-miR-4535 expression. Taken together, our findings indicate a link between hsa-miR-4535 and TGFß/Smad collagen synthesis signaling and suggest these factors to be involved in the photo-protective mechanism of galangin in dermal fibroblasts against H2O2/UVB-induced aging. The evidence indicated that galangin with anti-aging properties can be considered as a supplement in skin care products.

Calcium Silicate-Activated Gelatin Methacrylate Hydrogel for Accelerating Human Dermal Fibroblast Proliferation and Differentiation.

Wound healing is a complex process that requires specific interactions between multiple cells such as fibroblasts, mesenchymal, endothelial, and neural stem cells. Recent studies have shown that calcium silicate (CS)-based biomaterials can enhance the secretion of growth factors from fibroblasts, which further increased wound healing and skin regeneration. In addition, gelatin methacrylate (GelMa) is a compatible biomaterial that is commonly used in tissue engineering. However, it has low mechanical properties, thus restricting its fullest potential for clinical applications. In this study, we infused Si ions into GelMa hydrogel and assessed for its feasibility for skin regeneration applications by observing for its influences on human dermal fibroblasts (hDF). Initial studies showed that Si could be successfully incorporated into GelMa, and printability was not affected. The degradability of Si-GelMa was approximately 20% slower than GelMa hydrogels, thus allowing for better wound healing and regeneration. Furthermore, Si-GelMa enhanced cellular adhesion and proliferation, therefore leading to the increased secretion of collagen I other important extracellular matrix (ECM) remodeling-related proteins including Ki67, MMP9, and decorin. This study showed that the Si-GelMa hydrogels were able to enhance the activity of hDF due to the gradual release of Si ions, thus making it a potential candidate for future skin regeneration clinical applications.