Polydimethylsiloxane (PDMS) is a biocompatible polymer that has been applied in many fields. However, the surface hydrophobicity of PDMS can limit successful implementation, and this must be reduced by surface modification to improve biocompatibility. In this study, we modified the PDMS surface with a hydrogel and investigated the effect of this on hydrophilicity, bacterial adhesion, cell viability, immune response, and biocompatibility of PDMS. Hydrogels were created from hyaluronic acid and gelatin using a Schiff-base reaction. The PDMS surface and hydrogel were characterized using nuclear magnetic resonance, X-ray photoelectron spectroscopy, attenuated total reflection Fourier-transform infrared spectroscopy, and scanning electron microscopy. The hydrophilicity of the surface was confirmed via a decrease in the water contact angle. Bacterial anti-adhesion was demonstrated for Pseudomonas aeruginosa, Ralstonia pickettii, and Staphylococcus epidermidis, and viability and improved distribution of human-derived adipose stem cells were also confirmed. Decreased capsular tissue responses were observed in vivo with looser collagen distribution and reduced cytokine expression on the hydrogel-coated surface. Hydrogel coating on treated PDMS is a promising method to improve the surface hydrophilicity and biocompatibility for surface modification of biomedical applications.

Background In recent years, the number of people riding stand-up electric scooters in South Korea has increased rapidly. This study analyzed the facial injury patterns associated with stand-up electric scooter-related trauma in patients who visited our emergency center.Methods In this retrospective review, we collected data from patients who had visited our emergency center for stand-up electric scooter-related trauma between January 1, 2018 and December 31, 2020.Results The average age of the patients was 26.7 years. Of the 73 patients, 47 were male and 26 were female, highlighting a male predominance. Seven patients were injured after alcohol consumption. None of the patients had worn helmets. Additionally, upon comparing the frequency of facial injuries according to the quarter of the year, the facial injury rate was higher in the second and third quarters than in the first and fourth quarters. Facial soft tissue injuries were classified into facial cosmetic subunits and analyzed according to their location. The highest number of injuries was on the chin (n=18, 20.9%). Of the 73 patients with stand-up electric scooter-related facial injuries, 16 had acute facial osseous fractures. The commonest acute facial osseous fractures were those of the orbit (n=7, 26.9%).Conclusions The patterns of facial trauma reported here can be helpful for quickly evaluating and treating patients with facial trauma related to stand-up electric scooters. Additionally, people riding stand-up electric scooters should be aware of the risks associated with facial trauma and the importance of wearing protective devices, such as helmets and masks.

Capsular contracture, which is the pathologic development of fibrous capsules around implants, is a major complication of reconstructive and aesthetic breast surgeries. Capsular contracture can cause implant failure with breast hardening, deformity, and severe pain. The exact mechanisms underlying this complication remain unclear. In addition, anaplastic large cell lymphoma is now widely recognized as a very rare disease associated with breast implants. Foreign body reactions are an inevitable common denominator of capsular contracture. A number of studies have focused on the associated immune responses and their regulation. The present article provides an overview of the currently available techniques, including novel nano/microtechniques, to reduce silicone implant-induced contracture and associated foreign body responses.

Tendon injuries are major musculoskeletal disorders. Polydeoxyribonucleotide activates the adenosine receptor subtype A2A, resulting in tissue growth and neogenesis. This experimental study confirms that polydeoxyribonucleotide can improve secretion of various growth factors, promote collagen synthesis, and restore tensile strength of the Achilles tendon in a rat model with Achilles tendon injury. Thirty-six male Sprague-Dawley rats, aged 7 weeks, were divided into two groups, and the Achilles tendon was transected and repaired using the modified Kessler's method. In the experimental group (n = 18), the rats received daily intraperitoneal administration of polydeoxyribonucleotide (8 mg/kg/day for 1, 2, or 4 weeks). The control groups received the same amount of normal saline. The rats were euthanized at 1, 2, and 4 weeks, and tissues from the repair site were harvested. The cross-sectional area of the tendon was significantly increased at 2 and 4 weeks in polydeoxyribonucleotide group (p = 0.008 and p = 0.017, respectively). Moreover, tendons in the polydeoxyribonucleotide group were more resistant to mechanical stress at 2 and 4 weeks (p = 0.041 and p = 0.041, respectively). The staining levels of collagen type I in the experimental group were significantly stronger at 2 and 4 weeks (p = 0.026 and p = 0.009, respectively). Furthermore, higher expression levels of fibroblast growth factor, vascular endothelial growth factor, and transforming growth factor β1 were detected in the experimental group at 4 weeks (p = 0.041, p = 0.026, and p = 0.041, respectively). This study confirms that polydeoxyribonucleotide can improve the tensile strength of the rats' Achilles tendon following injury and repair. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1767-1776, 2018.

Background This is the first clinical study conducted among Asian women using breast implants manufactured by an Asian company. Four-year data regarding the safety and efficacy of BellaGel breast implants have already been published, and we now report 6-year data.Methods This study was designed to take place over 10 years. It included 103 patients who underwent breast reconstruction or augmentation using BellaGel breast implants. The rates of implant rupture and capsular contracture were measured and analyzed to evaluate the effectiveness of the breast implant.Results At patients’ 6-year postoperative visits, the implant rupture and capsular contracture rates were 1.15% and 2.30%, respectively. The implant rupture rate was 3.77% among reconstruction cases and 0% among augmentation cases. The capsular contracture rate was 5.66% among reconstruction cases and 0.83% among augmentation cases.Conclusions The 6-year data from this planned 10-year study suggest that the BellaGel cohesive silicone gel-filled breast implant is an effective and safe medical device that can be used in breast reconstruction and augmentation.