Evaluation of Non-invasive Fat Reduction Using a Resistive Electric Transfer-based Radiofrequency Device With Multi-channel Handpieces.

BACKGROUND/AIM: Various devices for non-invasive body shape correction are being developed along with the growth of the beauty industry. Radiofrequency (RF) can selectively reduce subcutaneous fat without causing skin damage. The efficacy of the procedure can be improved by applying RF to a large area simultaneously with multiple handpieces. This study evaluated the safety and efficacy of a new RF device with multi-channel handpieces. MATERIALS AND METHODS: In ex vivo experiments, the RF device was used to treat porcine tissue comprising the skin, subcutaneous, and muscle layers. The device's safety was evaluated by temperature measurements of porcine tissue and histological analysis. In in vivo experiments, the dorsal skin of pigs was treated with the RF device. The safety and efficacy of the device were evaluated by measuring the skin temperature, subcutaneous fat layer thickness, and conducting histological analysis. RESULTS: The skin temperature did not exceed the set temperature during treatment, and skin damage was not observed in histologic analysis in both ex vivo and in vivo experiments. In in vivo experiments, the subcutaneous fat layer thickness and subcutaneous lipocyte size were decreased after treatment. In addition, the fibrous tissue between subcutaneous lipocytes was increased in the RF treatment group compared with the non-treatment group. CONCLUSION: The RF device used in this study effectively reduced the size of subcutaneous lipocytes and increased fibrous tissue without skin damage. Therefore, the safe and effective use of this device for non-invasive fat reduction may be possible in clinical settings.

A novel acrylic orthodontic device for treatment of linguoverted mandibular canine teeth in small dogs.

Linguoverted mandibular canine teeth (LMC) is a common malocclusion in dogs. Several inclined bite-plane techniques using acrylic resin have been introduced to correct LMC in dogs. Although these techniques have suggested modifications to overcome shortcomings, there are still limitations; e.g., high technical sensitivity, as the viscous acrylic resin must still be fabricated in the oral cavity. The authors developed a novel method for small-breed dogs that uses a doughy acrylic resin form to achieve an easy intraoral design and extraoral fabrication. Eight small-breed dogs were presented to evaluate and treat malocclusion causing palatal trauma. First, a Class-1 malocclusion with linguoversion of the mandibular canine teeth (6 dogs with unilateral LMC and 2 dogs with bilateral) was diagnosed based on oral examination. Dogs were treated with the new method using a doughy acrylic resin form for 6 to 7 wk and had posttreatment follow-up 1 y after the procedure. All treated canine teeth were in correct positions 1 y after the appliances were removed. Key clinical message: The authors believe that the new method using a doughy acrylic resin form could be a good alternative for veterinarians to use when treating LMC.

Un nouveau dispositif orthodontique en acrylique pour le traitement des canines mandibulaires linguoverties chez les petits chiens. Les canines mandibulaires linguoverties (LMC) sont une malocclusion courante chez le chien. Plusieurs techniques de plan de morsure incliné utilisant de la résine acrylique ont été introduites pour corriger la LMC chez le chien. Bien que ces techniques aient suggéré des modifications pour surmonter les lacunes, elles présentent encore des limites; par exemple, une sensibilité technique élevée, car la résine acrylique visqueuse doit encore être fabriquée dans la cavité buccale. Les auteurs ont développé une nouvelle méthode pour les chiens de petite race qui utilise une forme pâteuse de résine acrylique pour obtenir une conception intra-orale et une fabrication extra-orale faciles. Huit chiens de petite race ont été présentés pour évaluer et traiter une malocclusion provoquant un traumatisme palatin. Tout d'abord, une malocclusion de classe 1 avec linguoversion des canines mandibulaires (6 chiens avec LMC unilatérale et 2 chiens avec bilatérale) a été diagnostiquée sur la base d'un examen oral. Les chiens ont été traités avec la nouvelle méthode en utilisant une forme pâteuse de résine acrylique pendant 6 à 7 semaines et ont fait l'objet d'un suivi post-traitement 1 an après la procédure. Toutes les canines traitées étaient dans la bonne position un an après le retrait des appareils.Message clinique clé:Les auteurs estiment que la nouvelle méthode utilisant une forme pâteuse de résine acrylique pourrait être une bonne alternative que les vétérinaires pourraient utiliser lors du traitement du LMC.(Traduit par Dr Serge Messier).

Outcomes of root canal treatments with three different sealers for 120 fractured maxillary fourth premolar teeth in small-to medium-sized dogs.

Introduction: Tooth fracture is one of the most common traumatic maxillofacial injuries in dogs and cats. For fractures with pulp exposure occurring in functionally important teeth, the literature indicates that root canal treatment (RCT) is an effective therapy option that may be the remedy of choice before extraction. The most commonly reported fractures in the United States involve canine teeth; however, fractures of the maxillary fourth premolars are more common in Korea, where there are many small-and medium-sized dogs. RCT mechanically and chemically removes pulp tissue and bacteria (cleaning and shaping) from the infected root canal, and obturates the root canal with filling material to restore tooth functionality without inflammation. Various techniques, instruments, and materials used in humans have been modified for application in veterinary dentistry. Methods: This study analyzed the results of RCT of the maxillary fourth premolar in 120 small-and medium-sized dogs (weighing less than 25 kg) using three different sealers (silicone-based sealer, bioceramic sealer, and calcium hydroxide-based sealer) through a simple application of the single-cone technique. Results: The overall success rate of RCT in maxillary fourth premolars was 90.83%, with 8.33% no evidence of failure (NEF) and 0.83% failure. Discussion: There were no significant differences between the three different sealers. Furthermore, preexisting periapical lesion (PAL) was reconfirmed as a factor in reducing the success rate of RCT. In addition, the working length and master apical file of each root were analyzed in our study as a novel reference for endodontic veterinarians.

Evaluation of Biocompatibility and Healing Properties of Dural Substitutes Produced by Electrospinning Technology.

BACKGROUND/AIM: Dural reconstruction is a critical process after neurosurgical procedures. Improper dural repair leads to serious side-effects, such as cerebrospinal fluid leakage or infection. This is why it is important to properly repair the dura using a dural substitute, and research into dural substitutes is ongoing. The ideal dural substitute should be non-toxic, biocompatible, and capable of maintaining adequate tension and preventing cerebrospinal fluid leakage for extended periods in vivo. This study evaluated the biocompatibility and healing properties of Safe-Seal, poly-L-lactic acid synthetic bioabsorbable dural substitute produced by electrospinning technology. MATERIALS AND METHODS: Safe-Seal, was created by electrospinning, which is a technique for nanofiberizing polymers into three-dimensional structures, and its cytotoxicity was evaluated. The animal study used 30 rats, divided into three groups assessed at two time points (4 and 12 weeks). The study groups were a negative control group with no treatment, an experimental group with Safe-Seal (TDM Co. Ltd., Gwangju, Republic of Korea) implantation, and a positive control group with a commercial product, Redura® (Medprin Biotech, Frankfurt, Germany) implantation. RESULTS: Safe-Seal exhibited no cytotoxic or adverse effects in the in vivo animal study. Histologically, Safe-Seal displayed less inflammatory cell infiltration, less adhesion to brain tissue, and connectivity with the surrounding dura mater as compared to the negative control group and without any significant differences from Redura® in all evaluation criteria. CONCLUSION: Safe-Seal presented adequate biocompatibility in vivo and contributed to the healing of the dura mater at a similar level to that of Redura® when applied to dural defects.

Application of modified porcine xenograft by collagen coating in the veterinary field: pre-clinical and clinical evaluations.

Introduction: This study aimed to identify a collagen-coating method that does not affect the physicochemical properties of bone graft material. Based on this, we developed a collagen-coated porcine xenograft and applied it to dogs to validate its effectiveness. Methods: Xenografts and collagen were derived from porcine, and the collagen coating was performed through N-ethyl-N'-(3- (dimethylamino)propyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS) activation. The physicochemical characteristics of the developed bone graft material were verified through field emission scanning electron microscope (FE-SEM), brunauer emmett teller (BET), attenuated total reflectance-fourier transform infrared (ATR-FTIR), and water absorption test. Subsequently, the biocompatibility and bone healing effects were assessed using a rat calvarial defect model. Results: The physicochemical test results confirmed that collagen coating increased bone graft materials' surface roughness and fluid absorption but did not affect their porous structure. In vivo evaluations revealed that collagen coating had no adverse impact on the bone healing effect of bone graft materials. After confirming the biocompatibility and effectiveness, we applied the bone graft materials in two orthopedic cases and one dental case. Notably, successful fracture healing was observed in both orthopedic cases. In the dental case, successful bone regeneration was achieved without any loss of alveolar bone. Discussion: This study demonstrated that porcine bone graft material promotes bone healing in dogs with its hemostatic and cohesive effects resulting from the collagen coating. Bone graft materials with enhanced biocompatibility through collagen coating are expected to be widely used in veterinary clinical practice.

Laparoscopic attenuation of a congenital extrahepatic portosystemic shunt in a dog-a thin-film banding for splenophrenic shunt: A case report.

A 6-year-old castrated male Shih-Tzu dog weighing 6. 5 kg presented with chief complaints of pollakiuria and urine dribbling. He had a history of urolithiasis for 3 years, which was confirmed by the presence of ammonium urate in the urinary stone analysis, performed 2 years prior to the presentation. Blood examination showed high values of fasting ammonia, post-prandial bile acid, and low blood urea nitrogen. Microhepatica and urolithiasis were identified on plain radiography and ultrasonography. A computed tomography angiography demonstrated a shunting vessel, diameter up to 9.6 mm, originated from the splenic vein, and linked with the phrenic vein. A surgical attenuation with a thin-film banding was performed under laparoscopic visualization. Left triangular ligament was incised, and one stay suture was placed to the stomach to expose the vessel. The shunting vessel was dissected before it entered the diaphragm, and a thin-film band was applied around the vessel. The patient recovered uneventfully without post-attenuation neurologic signs. Portal vein diameter increased with time, and complete closure of the shunting vessel was identified on computed tomography angiography performed at 14 months after attenuation. The patient was doing well for 31 months after surgery without protein restriction. This is a report of laparoscopic attenuation for splenophrenic type of canine congenital extrahepatic portosystemic shunt with a favorable outcome using thin-film banding.

Effects of a Topically Applied Oral Wound Dressing Film on Intra-oral Wound Healing in Rabbits.

BACKGROUND/AIM: Oral lesions are a common clinical symptom that can impair the quality of life of patients. Several treatments have been developed; however, therapies for wounds on the oral mucosa are symptomatic and unsatisfactory. This study aimed to evaluate the efficacy of an oral wound dressing (OWD) film in healing excision and chemical burns using a rabbit oral wound model and to demonstrate the effect of physical barriers during wound healing. MATERIALS AND METHODS: Excision and chemical burn wounds were induced on the oral hard palate of animals. Four experimental groups were established. The OWD film was applied immediately after surgery and replaced every 24 h over the following 3 days. The animals were sacrificed at 3, 7, and 14 days after surgery. The hard palate tissues were analyzed by histological and immunohistochemical evaluation. The degree of epithelialization, number of proliferating cells, and collagen deposition were evaluated. Statistical significance was analyzed using the Student's t-test. RESULTS: Following application of the OWD film to the excision and chemical burn wounds, the OWD treatment group's epithelial gap and proliferation showed a significant difference compared to those of the untreated group during the proliferative stage of wound healing. However, there was no difference in the epithelial gap in the chemical burn wound model, whereas the OWD treatment group showed a significantly reduced ulcerated area. Collagen deposition in the OWD treatment group was significantly increased during the remodeling stage of wound healing. CONCLUSION: The OWD film treatment promoted wound healing in the oral mucosa by accelerating wound closure and reconstruction.

In Vivo Evaluation of Gamma-Irradiated and Heparin-Immobilized Small-Diameter Polycaprolactone Vascular Grafts with VEGF in Aged Rats.

The effectiveness of small-diameter vascular grafts depends on their antithrombogenic properties and ability to undergo accelerated endothelialization. The extreme hydrophobic nature of poly(ε-caprolactone) (PCL) hinders vascular tissue integration, limiting its use in medical implants. To enhance the antithrombogenicity of PCL as a biomaterial, we grafted 2-aminoethyl methacrylate (AEMA) hydrochloride onto the PCL surface using gamma irradiation; developed a biodegradable heparin-immobilized PCL nanofibrous scaffold using gamma irradiation and N-(3-dimethylaminopropyl)-N'-ethyl carbodiimide hydrochloride/N-hydroxysuccinimide reaction chemistry; and incorporated vascular endothelial growth factor (VEGF) into the scaffold to promote vascular endothelial cell proliferation and prevent thrombosis on the vascular grafts. We assessed the physicochemical properties of PCL, heparin-AEMA-PCL (H-PCL), and VEGF-loaded heparin-AEMA-PCL (VH-PCL) vascular grafts using scanning electron microscopy, attenuated total reflection-Fourier transform infrared spectroscopy, toluidine blue O staining, and fibrinogen adsorption and surface wettability measurement. In addition, we implanted the vascular grafts into 24-month-old Sprague Dawley rats and evaluated them for 3 months. The H-PCL and VH-PCL vascular grafts improved the recovery of blood vessel function by promoting the proliferation of endothelial cells and preventing thrombosis in clinical and histological evaluation, indicating their potential to serve as functional vascular grafts in vascular tissue engineering.

A Safety Test for Ocular Phototoxicity in the Rabbit After Short-term Exposure to Strong Light.

BACKGROUND/AIM: Self-defense products that use high-intensity light are being developed. The intense light generated by the high-power light-emitting diodes (LEDs) of such self-defense products causes temporary blindness. However, few studies have been conducted on the visual safety of their devices. We, therefore, evaluated the effects of strong light of a short duration on the eyes of rabbits in this study. MATERIALS AND METHODS: The right eyes of 15 rabbits were irradiated for 5 s with a lighting device (25 W, 150 lm/W at 700 mA LED) and four eyes of two rabbits were non-irradiated as controls. Changes in the eye structure and function were evaluated before, and immediately, 30 min, 1 h, 24 h, 7 days and 14 days after light irradiation by full-field electroretinogram (ERG), slit-lamp biomicroscopy, and retinal camera. The thickness of the outer nuclear layer of the retina tissue was measured, and histopathological signs of retinal damage were analyzed. RESULTS: The ERG results showed that night vision was not affected. In day vision, the ERG waveform was temporarily affected immediately after light irradiation; however, it recovered within 24 h. No histopathological signs of damage were observed. CONCLUSION: Application of high-power LED light with short duration as used for self-defense was found to cause temporary phototoxicity, but safety was confirmed as vision recovered within 24 h.

Therapeutic Efficacy of Artificial Skin Produced by 3D Bioprinting.

The skin protects the body from external barriers. Certain limitations exist in the development of technologies to rapidly prepare skin substitutes that are therapeutically effective in surgeries involving extensive burns and skin transplantation. Herein, we fabricated a structure similar to the skin layer by using skin-derived decellularized extracellular matrix (dECM) with bioink, keratinocytes, and fibroblasts using 3D-printing technology. The therapeutic effects of the produced skin were analyzed using a chimney model that mimicked the human wound-healing process. The 3D-printed skin substitutes exhibited rapid re-epithelialization and superior tissue regeneration effects compared to the control group. These results are expected to aid the development of technologies that can provide customized skin-replacement tissues produced easily and quickly via 3D-printing technology to patients.

Treatment of two Asiatic black bears (Ursus thibetanus) with severe injuries and their subsequent release into the wild: a case report.

BACKGROUND: The rehabilitation of injured wildlife and their subsequent release into the wild is a humane act as well as important in wildlife conservation. However, little is known about the animals' fate after release. Therefore, to address these uncertainties, it is essential to adequately describe how the injured animals were treated and managed before releasing into the wild; moreover, post-release monitoring should also be performed. Herein, we document for the first time the process of rescue, surgery, and rehabilitation of severely injured Asiatic black bears (Ursus thibetanus; endangered species in South Korea) and their fate after returning to the wild. CASE PRESENTATION: A six-year-old female (bear-01) and a three-year-old male (bear-02) bears were injured by an illegal snare and collision with a bus, respectively. Bear-01 had broad muscle necrosis and ruptures from the snared ankle on the right thoracic limb, with myiasis, and elbow disarticulation was performed. In bear-02, a non-reducible comminuted fracture of the left humerus was confirmed radiologically, and the operation was performed by using dual plate fixation with hydroxyapatite and recombinant human bone morphogenetic protein-2. The bear-01 and -02 were completely healed approximately 30 and 60 days after surgery, respectively. After that, they underwent rehabilitation for 8 and 25 days, respectively, in an outdoor enclosure similar to their natural habitat. Bear-01 and -02 were released into the wild after 45 and 99 days after surgery, respectively, and their mean daily movement distance during the first 30 days after releasing was 2.9 ± 2.1 and 1.3 ± 1.6 km, respectively. The annual mean 95% Kernel home-range size of bear-01 and bear-02 was 265.8 and 486.9 km2, respectively. They hibernated every winter, gained weight, gave birth to cubs (bear-01), were not found to have any abnormalities in the veterinary tests, and were not involved in any conflicts with humans after returning to the wild. CONCLUSIONS: Bears without one leg or those with dual plates could adapt well in their natural habitat, which shows that our surgical and post-operative treatments were effective. Additionally, minimizing human contact and observing/evaluating behavior during the rehabilitation is essential in reducing human-bear conflicts after release.

Successful Clinical Application of Cancellous Allografts With Structural Support for Failed Bone Fracture Healing in Dogs.

BACKGROUND/AIM: In Korea, small breed dogs including Maltese, Pomeranians, and Yorkshire Terriers are most common. These small dogs are at increased risk for the development of delayed union or nonunion fractures, particularly when the fracture occurs at a site with insufficient surrounded soft tissue such as the ulna and radius. To treat failed bone fracture healing, stable fixation of the fracture and implantation of bone grafts are needed. Among the various types of bone grafts, autograft is considered to be the gold standard. However, the amount of autograft available for harvesting in small dogs is limited. In this study, we report on a novel canine cancellous allograft (C350C) that was prepared using chemicals and low heat treatment (350°C). PATIENTS AND METHODS: We applied C350C in two cases with failed bone fracture healing. Due to the poor osteoinductive capabilities of C350C, we also used recombinant human bone morphogenetic protein-2 (rhBMP-2) and Matrigel as osteoinductive and delivery agents, respectively. RESULTS: In both cases, the fractures healed successfully. CONCLUSION: C350C can be used as a bone graft material that could replace autografts in cases with failed bone fracture healing.

Evaluation of Porcine Hybrid Bone Block for Bone Grafting in Dentistry.

BACKGROUND/AIM: The purpose of this study was to develop hybrid bone blocks using porcine-derived collagen and low crystalline porcine-derived hydroxyapatite to overcome the disadvantages of commonly used bone grafts in dentistry. MATERIALS AND METHODS: Collagen was added to hydroxyapatite particles to increase the spatial integration of particulate bone grafts. Physicochemical examination and in vivo tests were performed to analyze scaffold's characteristics and evaluate bone regeneration. RESULTS: Porcine hybrid bone block had an irregular and interconnecting macroporous structure that was adequate for bone regeneration and bone ingrowth, and showed a good space-occupying ability to become well positioned. In addition, it showed higher angiogenesis and biodegradability than Bio-Oss Collagen®, a commercialized bone graft used in dental clinics. CONCLUSION: Our results suggest that improved collagen hybrid bone block can be generated when porcine cancellous bone particles and collagen were reasonably mixed. This hybrid bone block was easy in handling had flexibility, good biodegradability and provided bone regeneration.

Immunological Compatibility of Bone Tissues from Alpha-1,3-galactosyltransferase Knockout Pig for Xenotransplantation.

We investigated whether the lack of galactosyltransferase (α-Gal) expression in bone tissue is associated with reduced immune response of human peripheral blood mononuclear cells (PBMCs) against pig bone tissue. When human PBMC obtained from heparinized blood of healthy volunteers was stimulated with bone extracts of pigs with α-1,3-galactosyltransferase knock out (α-Gal KO), the proliferation of human PBMCs and production of proinflammatory cytokines such as TNF-α and IL-1ß were significantly reduced compared to those stimulated with bone extracts of wild type (WT) pigs. In addition, activation of CD4+ helper T cells and production of IL-2, IFN-γ, and IL-17 were reduced upon stimulation with bone tissue extracts from α-Gal KO pigs. This is possibly due to the lowered activities of the NF-κB, p38, ERK, and JNK signaling pathways. Our findings can be used to evaluate the compatibility of bone tissues from α-Gal KO pigs with human bone grafting as novel natural biomaterials, thereby increasing the feasibility of future clinical applications.

Three-Dimensional Printing-based Reconstruction of a Maxillary Bone Defect in a Dog Following Tumor Removal.

Three-dimensional (3D) printing has been applied extensively not only in human, but also veterinary medicine. However, the technique is still used in the clinical area for a surgical plan or education prior to surgery. Thus, we report a case of reconstruction after tumor removal surgery with the use of a 3D-printed scaffold. A 12-year-old female mixed dog had a left caudal maxillary mass. Based on computed tomography images, a defect was confirmed on the maxillary bone due to the oral mass, and a surgical plan was designed to remove the oral mass and graft the 3D printed scaffold. Customized polycaprolactone/ beta-tracalciumphosphate (PCL/ß-TCP) scaffold was fabricated using the micro-extrusion-based 3D printer. In the operation, after the removal of the oral mass, the scaffold was grafted onto the defect site. At follow-up, 8 months after surgery, the result was successful without any special problems in the periodic CT scans and oral examinations. This case is believed to be the first case of reconstruction by using a 3D printed scaffold in the maxillary bone defect, and this 3D printing technique is thought to be very helpful for veterinary patients with bone defects and several other diseases.