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Guiding endogenous regeneration of bone defects using biomaterials and regenerative medicine is considered an optimal strategy. One of the effective therapeutic approaches involves using transgene-expressed stem cells to treat tissue destruction and replace damaged parts. Among the various gene editing techniques for cells, clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) is considered as a promising method owing to the increasing therapeutic potential of cells by targeting specific sites. Herein, a vitamin D-incorporated poly(lactic-co-glycolic acid) (PLGA) scaffold with bone morphogenetic protein 2 (BMP2)/vascular endothelial growth factor (VEGF)-overexpressed tonsil-derived MSCs (ToMSCs) via CRISPR/Cas9 was introduced for bone tissue regeneration. The optimized seeding ratio of engineered ToMSCs on the scaffold demonstrated favorable immunomodulatory function, angiogenesis, and osteogenic activity in vitro. The multifunctional scaffold could potentially support stem cell in vivo and induce the transition from M1 to M2 macrophage with magnesium hydroxide and vitamin D. This study highlights the improved synergistic effect of a vitamin D-incorporated PLGA scaffold and a gene-edited ToMSCs for bone tissue engineering and regenerative medicine.

The skin is the largest organ and a crucial barrier for protection against various intrinsic and extrinsic factors. As we age, the skin's components become more vulnerable to damage, forming wrinkles. Among different procedures, hyaluronic acid-based hydrogel has been extensively utilized for skin regeneration and reducing wrinkles. However, it has limitations like low retention and weak mechanical properties. In this study, we suggested the poly(l-lactic acid) (PLLA) microparticles containing alkaline magnesium hydroxide and nitric oxide-generating zinc oxide and rejuvenative hyaluronic acid (HA) hydrogels including these functional microparticles and asiaticoside, creating a novel delivery system for skin rejuvenation and regeneration. The fabricated rejuvenative hydrogels have exhibited enhanced biocompatibility, pH neutralization, reactive oxygen species scavenging, collagen biosynthesis, and angiogenesis capabilities in vitro and in vivo. Additionally, an excellent volume retention ability was demonstrated due to the numerous hydrogen bonds that formed between hyaluronic acid and asiaticoside. Overall, our advanced injectable hydrogel containing functional microparticles, with controlled release of bioactive molecules, has a significant potential for enhancing the regeneration and rejuvenation of the skin.

Flap surgery is a common method used to cover defects following tumor ablation, trauma, or infection. However, insufficient vascularity in the transferred flap can lead to flap necrosis and failure. Proper postoperative monitoring is essential to prevent these complications. Recently, research has explored the use of infrared thermal imaging in plastic surgery, leading to its clinical application. This study comprises two separate parts: an in vivo experimental study and a clinical study. In this study, 28 rats underwent reverse McFarlane flap surgery, and their flaps were analyzed using a FLIR thermal imaging camera seven days post-surgery. Additionally, thermal images of flaps were taken on postoperative days 0, 1, 2, 3, and 7 in 22 patients. This study focused on temperature differences between normal skin and the perforator compared to the average flap temperature. Results showed that the temperature difference was higher in the necrosis group and increased over time in cases of total necrosis. A lower perforator temperature compared to the flap’s average indicated vascular compromise, potentially leading to flap failure. The FLIR camera, being contact-free and convenient, shows promise for understanding and inferring the clinical progression of flaps in postoperative monitoring.

With the development of minimally invasive approaches, calcium-based injectable bone paste has attracted attention as a synthetic alternative due to its biodegradability and analogous composition with native bone. However, this approach is associated with the problem of the materials being absorbed before new bone formation has occurred, with a high resorption, and degradation rate. Here, a poly(lactic-co-glycolic acid) (PLGA)/magnesium hydroxide (MH)/vitamin D (Vit D) microsphere-incorporated α-calcium sulfate hemihydrate (α-CSH)/beta-tricalcium phosphate (β-TCP) injectable paste was designed for the regeneration of bone tissue. The combination of the bioceramic particles with α-CSH demonstrated an appropriate setting time for ease of use in clinical practice and enhanced mechanical properties. Additionally, the introduction of a bone paste with the MH and Vit D-incorporated PLGA microsphere induced osteogenic differentiation and alleviated the inflammatory response, which may occur after massive bone surgery. Based on these findings, this paper presents a versatile bone paste that promotes osteogenesis and modulates the osteoimmune microenvironment for effective bone regeneration.

Abstract Background Coronary artery disease is a cardiovascular disease with a high mortality and mortality rate in modern society. Vascular stent insertion to restore blood flow is essential to treat this disease. A fully biodegradable vascular scaffold (BVS) is a vascular poly (L-lactic acid) (PLLA) stent that is receiving growing interest as this is biodegradable in the body and does not require secondary removal surgery. However, acidic byproducts composed of PLLA produced during the biodegradation of the BVS can induce an inflammatory response. Magnesium hydroxide, a basic inorganic particle, neutralizes the acidic byproducts of PLLA. Methods In this study, we investigated using a BVS coated with everolimus and surface-modified magnesium hydroxide that suppresses smooth muscle cell proliferation and protects endothelial cells, respectively. The various characteristics of the functional stent were evaluated using in vitro and in vivo analyses. Results The BVS was successfully prepared with evenly coated everolimus and surface-modified magnesium hydroxide. A neutral pH value was maintained by magnesium hydroxide during degradation, and everolimus was released for one month. The coated BVS effectively inhibited protein adsorption and platelet adhesion, demonstrating excellent blood compatibility. In vitro analysis showed that BVS protects endothelial cells with magnesium hydroxide and selectively inhibits smooth muscle cell proliferation via everolimus treatment. The functional BVS was inserted into porcine coronary arteries for 28 days, and the results demonstrated that the restenosis and inflammation greatly decreased and re-endothelialization was enhanced as compared to others. Conclusions This study provides new insights into the design of drug-incorporated BVS stent for coronary artery disease. Graphical Abstract

A 51-year-old man was referred for a skin defect with paresthesia and decreased pain in his right ala. He had a history of herpes zoster infection 3 weeks previously. Excisional biopsy and culture showed no evidence of skin malignancy or infection. He was diagnosed with trigeminal trophic syndrome (TTS) after herpes zoster infection. A two-stage folded nasolabial flap was used to reconstruct the defect. The patient was satisfied with the cosmetic outcomes of surgery, and there was no evidence of recurrence during the follow-up. TTS, a rare skin condition that presents with paresthesia, anesthesia, and facial ulceration, occurs after trigeminal nerve injury, which can be caused by herpes zoster infection in rare cases. TTS is an often-persistent condition with a high recurrence rate, causing cosmetic problems. Some surgical methods have been attempted, but our case presents the first use of a folded nasolabial flap to treat TTS. The flap was symmetric, without any nostril collapse. It is also noteworthy that the outcome was excellent with only a skin flap that did not use a bony framework. Herein, we report a rare case of TTS that occurred after herpes zoster infection and was successfully treated with a folded nasolabial flap.

Tendinopathy is a term used to describe tendon disorders that are marked by pain and a loss of function. Recent studies demonstrated that inflammation plays an important role throughout the broad spectrum of tendinopathy. Conventional treatments such as steroid injections, analgesics, and physical modalities simply give pain relief and do not alter the disease progression without the tendon regeneration effect. Tenocytes are responsible for maintaining the tendon matrix and understanding how they function is essential to studying new treatments for tendinopathy. Our previous study showed the protective effects of vitamin D (Vit D) on damaged tenocytes. Besides its well-known effects on bone metabolism, the non-classical action of Vit D is the pleiotropic effects on modulating immune function. In the present study, we developed a Vit D delivery system with hyaluronic acid (HA), which is one of the major components of the extracellular matrix that has anti-inflammation and wound-healing properties. A novel Vit D delivery system with cross-linked HA hydrogel (Gel) and Tween 80 (T80), Vit D@Gel/T80, could be a new regeneration technique for the treatment of tendinopathy. Vit D@Gel/T80 reduced TNF-α induced damage to human tenocytes in vitro. In an animal study, the Vit D@Gel/T80 injected group demonstrated tendon restoration features. As a result, this Vit D@Gel/T80 system might be a local injection material in the treatment for tendinopathy.

Background Latissimus dorsi (LD) flaps are often used in breast reconstruction procedures, but seroma formation is a frequent complication. To decrease the incidence of seroma formation, fibrin sealants and/or quilting sutures have been proposed, with controversial results. The primary objective of this study was to assess the effectiveness of the Harmonic scalpel in association with Tisseel and three-point deep dermal sutures in reducing the incidence of this complication. Methods A retrospective study was conducted of 108 patients undergoing immediate unilateral breast reconstruction with LD flaps over a 3-year period (2016–2018) by a single surgeon. In the experimental group, 37 patients underwent the procedure with a Harmonic scalpel and three-point deep dermal sutures (a modified version of quilting sutures), and the other 71 received conventional electrocautery. Fibrin sealant was applied to the donor site of all patents to reduce seroma formation. Results Statistically significant differences in the incidence of seroma were found between the two groups. There was a lower incidence of seroma formation in the group of patients treated with a Harmonic scalpel and three-point deep dermal sutures than in the other group. The total drainage amount and drain removal date between the two groups were not significantly different. Conclusions Within the limitations of this study, we suggest that Harmonic scalpel use can be a good choice among the many ways to reduce seroma formation following LD flap procedures, and that this technique will be very helpful for patients.

The development of a biodegradable vascular scaffold (BVS) for the treatment of cardiovascular diseases (CVDs) still requires some improvement. Among them, re-endothelialization and anti-inflammation are clinically important to restore vascular function. In this study, we proposed a coating system to deliver hydrophilic bioactive agents to BVS using nanoemulsion and drop-casting methods. The poly(L-lactide) (PLLA) scaffold containing magnesium hydroxide (MH) was coated on the surface with bioactive molecules such as polydeoxyribonucleotide (PDRN), L-arginine (Arg, R), and mesenchymal stem cell-derived extracellular vesicles (EVs). PDRN upregulates the expression of VEGF as one of the A2A receptor agonists; and Arg, synthesized into nitric oxide by intracellular eNOS, induces endothelialization. In particular, EVs, which are composed of a lipid bilayer and transfer bioactive materials such as protein and nucleic acid, regulate homeostasis in blood vessels. Such a bioactive agent coating system and its PLLA composite suggest a new platform for the treatment of cardiovascular dysfunction.

Poly(L–lactic acid) (PLLA), as a biodegradable polymer, has attracted attention for use as a biomaterial. In order to apply PLLA as a cardiovascular stent, stronger mechanical properties and anti–inflammatory effects against acidic by–products are required. In this study, PLLA/PDLA stereocomplex microparticles (SC) were developed and surface–modified magnesium hydroxide (MH) nanoparticles with oligolactide were combined with these PLLA composites. The SC improved the mechanical properties of the PLLA composites through the formation of stereocomplex structures. The surface–modified MH nanoparticles showed enhanced mechanical properties due to the stereocomplex structures formed by PLLA chains and inhibited inflammatory responses by pH neutralization as a result of MH. Additionally, the MH nanoparticles containing PLLA composites had antibacterial effects and increased the viability of human vascular endothelial cells. This technology is expected to have great potential in the development of PLLA composite materials for the production of various medical devices, such as cardiovascular stents.

Blepharoplasty is one of the most popular cosmetic surgical procedures for people who are concerned with minimizing the effects of aging and maintaining an aesthetically attractive appearance. If periorbital surgery is not performed by an expert, the risk of complications increases. In particular, retrobulbar hematoma, which is the most serious complication after blepharoplasty, can lead to permanent blindness. We report a rare case of unilateral permanent blindness due to careless and unprofessional treatment following a retrobulbar hematoma after lower blepharoplasty. In conclusion, it is necessary to check for symptoms and signs including pain, proptosis, visual acuity, and light reflex after the operation. Careful instructions should then be given to patients and their caregivers to avoid actions that may cause postoperative bleeding. We emphasize that if a patient complains of symptoms, painkillers should not be used and computed tomography should be performed for an accurate and rapid diagnosis. Appropriate procedures must then be taken to prevent permanent vision loss.

Poly(L-lactic acid) (PLLA) has attracted a great deal of attention for its use in biomedical materials such as biodegradable vascular scaffolds due to its high biocompatibility. However, its inherent brittleness and inflammatory responses by acidic by-products of PLLA limit its application in biomedical materials. Magnesium hydroxide (MH) has drawn attention as a potential additive since it has a neutralizing effect. Despite the advantages of MH, the MH can be easily agglomerated, resulting in poor dispersion in the polymer matrix. To overcome this problem, oligo-L-lactide-ε-caprolactone (OLCL) as a flexible character was grafted onto the surface of MH nanoparticles due to its acid-neutralizing effect and was added to the PLLA to obtain PLLA/MH composites. The pH neutralization effect of MH was maintained after surface modification. In an in vitro cell experiment, the PLLA/MH composites including OLCL-grafted MH exhibited lower platelet adhesion, cytotoxicity, and inflammatory responses better than those of the control group. Taken together, these results prove that PLLA/MH composites including OLCL-grafted MH show excellent augmented mechanical and biological properties. This technology can be applied to biomedical materials for vascular devices such as biodegradable vascular scaffolds.

Current approaches of biomaterials for the repair of critical-sized bone defects still require immense effort to overcome numerous obstacles. The biodegradable polymer-based scaffolds have been required to expand further function for bone tissue engineering. Poly(lactic-co-glycolic) acid (PLGA) is one of the most common biopolymers owing to its biodegradability for tissue regenerations. However, there are major clinical challenges that the byproducts of the PLGA cause an acidic environment of implanting site. The critical processes in bone repair are osteogenesis, angiogenesis, and inhibition of excessive osteoclastogenesis. In this study, the porous PLGA (P) scaffold was combined with magnesium hydroxide (MH, M) and bone-extracellular matrix (bECM, E) to improve anti-inflammatory ability and osteoconductivity. Additionally, the bioactive polydeoxyribonucleotide (PDRN, P) was additionally incorporated in the existing PME scaffold. The prepared PMEP scaffold has pro-osteogenic and pro-angiogenic effects and inhibition of osteoclast due to the PDRN, which interacts with the adenosine A2A receptor agonist that up-regulates expression of vascular endothelial growth factor (VEGF) and down-regulates inflammatory cytokines. The PMEP scaffold has superior biological properties for human bone-marrow mesenchymal stem cells (hBMSCs) adhesion, proliferation, and osteogenic differentiation in vitro. Moreover, the gene expressions related to osteogenesis and angiogenesis of hBMSCs increased and the inflammatory factors decreased on the PMEP scaffold. In conclusion, it provides a promising strategy and clinical potential candidate for bone tissue regeneration and repairing bone defects.

Gynecomastia refers to persistent enlargement of the breast in males caused by enlargement of the breast bud and surrounding stroma. It typically occurs in newborns, during early adolescence, and in late adulthood. There are several pathological causes. If no pathological cause is evident, gynecomastia is considered idiopathic. The reported prevalence of unilateral gynecomastia is approximately 35% to 45%, but most previous reports have focused on distinctive pathologic causes. As such, few previous reports of idiopathic unilateral gynecomastia during early adolescence have been published. Herein, we report a case of idiopathic unilateral gynecomastia in an adolescent male.