Sang Tae Ahn

In vivo cartilage formation using chondrogenic-differentiated human adipose-derived mesenchymal stem cells mixed with fibrin glue.

Human adipose-derived mesenchymal stem cells (MSCs) were differentiated into chondrogenic MSCs, and fibrin glue was used together to explore the feasibility of whether cartilages can be generated in vivo by injecting the differentiated cells. Mesenchymal stem cells extracted from human adipose were differentiated into chondrogenic MSCs, and such differentiated cells mixed with fibrin glue were injected subcutaneously into the back of the nude mouse. In addition to visual evaluation of the tissues formed after 4, 8, and 12 weeks, hematoxylin-eosin staining, Masson trichrome staining, measurement of glycosaminoglycan concentration using dimethylmethylene blue, agreecan through reverse transcriptase-polymerase chain reaction, type II collagen, and expression of SOX-9 were verified. Moreover, the results were compared with 2 groups of controls: 1 control group that received only injection of chondrogenic-differentiated MSC and the supporting control group that received only fibrin glue injection. For the experimental group, cartilage-like tissues were formed after 4, 8, and 12 weeks. Formation of cartilage tissues was not observed in any of 4, 8, and 12 weeks of the control group. The supporting control group had only a small structure formation after 4 weeks, but the formed structure was completely decomposed by the 8th and 12th weeks. The range of staining dramatically increased with time at 4, 8, and 12 weeks in Masson trichrome staining. The concentration of glycosaminoglycan also increased with time. The increased level was statistically significant with more than 3 times more after 8 weeks compared with 4 weeks and more than 2 times more after 12 weeks compared with 8 weeks. Also, in reverse transcriptase-polymerase chain reaction at 4, 8, and 12 weeks, all results expressed a cartilage-specific gene called aggrecan, type II collagen, and SOX-9. The study verified that the chondrogenic-differentiated MSCs derived from human adipose tissues with fibrin glue can proliferate and form new cartilage. Our findings suggest that formation of cartilages in vivo is possible.

Platelet supernatant promotes proliferation of auricular chondrocytes and formation of chondrocyte mass.

&NA; Recently proposed procedures for in vitro generation of new cartilage may be difficult to perform in humans because so many chondrocytes are needed for tissue engineering. In this study the authors investigated new, efficient, low‐cost techniques for the isolation and culture of chondrocytes from the ear cartilage of the rabbit. They performed a low‐density monolayer culture with a low concentration (0.5%, 1%) of human platelet supernatant and observed cell proliferation (seeding efficiency, deoxyribonucleic acid synthesis), matrix synthesis (glycosaminoglycan synthesis), and the expression of type I and type II collagen (reverse transcriptase polymerase chain reaction). Seeding efficiency was increased in 1% of platelet supernatant‐treated cultures by two to three times compared with untreated controls. One percent platelet supernatant had increased the incorporation of [3H]‐thymidine by 1.9 to 2.5 times at 72 hours compared with controls. Glycosaminoglycan synthesis was increased in platelet supernatant‐treated chondrocytes at 96 hours compared with controls. Chondrocytes treated with 1% platelet supernatant showed a decreased expression of the type II collagen gene. Supplementation with a high concentration (10%) of the platelet supernatant provided the conditions for the in vitro chondrocyte mass formation. These results indicate that proliferation and matrix synthesis of auricular chondrocytes is stimulated by a low concentration of platelet supernatant. On the other hand, chondrocytes were immobilized by a high concentration of platelet supernatant. Platelet supernatant may be useful as an inexpensive autologous source of multiple growth factors to enhance chondrocyte proliferation, and also may play the role of scaffold for chondrocytes. Additional investigation is underway to generate culture conditions that promote the differentiation as well as the proliferation of chondrocytes. Yang SY, Ahn ST, Rhie JW, Lee KY, Choi JH, Lee BJ, Oh GT. Platelet supernatant promotes proliferation of auricular chondrocytes and formation of chondrocyte mass. Ann Plast Surg 2000;44:405‐411

Single Transconjunctival Incision and Two-point Fixation for the Treatment of Noncomminuted Zygomatic Complex Fracture

The ultimate goal in treating zygomatic complex fracture is to obtain an accurate, stable reduction while minimizing external scars and functional deformity. The present authors present our experiences with a single transconjunctival incision and two-point (inferior orbital rim and frontozygomatic suture) fixation in 53 patients with zygomatic complex fracture which were not comminuted. All patients had transconjunctival approaches with lateral canthal extensions, and six out of 53 patients also had an additional small (about less than 2 cm) gingivobuccal incision to achieve an accurate reduction. There were 3 minor complications, and the overall esthetics and functional results were satisfactory with a long term follow-up. Our method has the following advantages in the reduction of zygomatic complex fracture; It leaves only an inconspicuous lateral canthal scar. In addition, it provides excellent simultaneous visualization of the inferior orbital rim and frontozygomatic suture area. Hence, two-point fixation through a single incision can be performed with a satisfactory stability.

Bone morphogenic protein-2 (BMP-2) immobilized biodegradable scaffolds for bone tissue engineering

Recombinant human bone morphogenic protein-2 (rhBMP-2), which is known as one of the major local stimuli for osteogenic differentiation, was immobilized on the surface of hyaluronic acid (HA)-modified poly(ε-caprolactone) (PCL) (HA-PCL) scaffolds to improve the attachment, proliferation, and differentiation of human bone marrow stem cells (hBMSCs) for bone tissue engineering. The rhBMP-2 proteins were directly immobilized onto the HA-modified PCL scaffolds by the chemical grafting the amine groups of proteins to carboxylic acid groups of HA. The amount of covalently bounded rhBMP-2 was measured to 1.6 pg/mg (rhBMP/HA-PCL scaffold) by using a sandwich enzyme-linked immunosorbant assay. The rhBMP-2 immobilized HA-modified-PCL scaffold exhibited the good colonization, by the newly differentiated osteoblasts, with a statistically significant increase of the rhBMP-2 release and alkaline phosphatase activity as compared with the control groups both PCL and HA-PCL scaffolds. We also found enhanced mineralization and elevated osteocalcin detection for the rhBMP-2 immobilized HA-PCL scaffolds, in vitro.

Modified gluteal fold V-Y advancement flap for vulvovaginal reconstruction.

AbstractThe gluteal fold V-Y advancement flap is a good option for the reconstruction of a vulvovaginal defect because it is thin, sensate, reliable, and has matched local skin quality. However, in situations where wider and deeper vulvovaginal reconstruction is needed, advancement of the flap alone may not be sufficient to create tension-free closure. To overcome these limitations, we designed a modified gluteal V-Y advancement flap, which has 1 or 2 additional transposition flaps at the base of the conventional advancement flap.This study includes a total number of 16 patients who had received vulvovaginal reconstruction with our new technique between March 2008 and April 2011. The causes of the defects were vulvar cancer in 13 patients and extramammary Paget disease in 3 patients. We examined the location and size of the defect, the flap design, and postoperative clinical courses. The mean follow-up period was 10.6 months, and the defect sizes ranged from 8 × 6 to 15 × 12 cm2. Overall, 11 of 16 patients were reconstructed with bilateral modified gluteal fold V-Y advancement flaps, and 5 patients were treated with a unilateral flap. All flaps survived without major complications, and the aesthetic and functional results were satisfactory. The modified gluteal fold V-Y advancement flap is useful and reliable for the reconstruction of wide and deep vulvovaginal defects. It can cover the defect without tension, and the complications associated with it are rare.

Surgical treatment of subcutaneous tophaceous gout.

1. STIEFEL BIOPSY PUNCH. 2 mm diameter, http://www. biopsypunch.com/biopsypunch.htm. Cost w £21.50 for pack of 10 (22.10.2009). 2. Palamarchuk HJ. An improved approach to evacuation of subungual hematoma. J Am Pod Med Assoc. 1989;79:566e9. 3. Ciocon D, Gowrishankar TR, Herndon T, et al. How low should you go: novel device for nail trephination. Dermatol Surg 2006 Jun;32:828e33. 4. Helms A, Brodell RT. Surgical pearl: prompt treatment of subungual hematoma by decompression. J Am Acad Dermatol 2000 Mar;42:508e9.

Perforators as recipients for free flap reconstruction of the inguinal and perineal region.

Extensive defects of the perineal or inguinal area require well vascularized free flap coverage. This area has an abundance of perforating arteries and veins based on vessels from the femoral artery and internal iliac artery. We present our experience on the use of perforators as recipient vessels in reconstructing soft tissue defects of the perineal and inguinal area with free flaps.

Treatment for Intramuscular Lipoma Frequently Confused with Sarcoma: A 6-Year Restrospective Study and Literature Review

Introduction. Intramuscular lipoma is a very rare form of lipoma, known to be categorized as an infiltrating lipoma due to its tendencies to infiltrate the muscle or the synovium. Contrary to other subcutaneous lipomas, even after surgical removal, the rate of local recurrence ranges at a high rate from 50∼80% and differential diagnosis with liposarcoma is very difficult. Patients and Methods. A retrospective chart review was conducted for a total of 27 patients. Before performing a surgery based on the types of mass, a radiologic imaging study was performed. An intraoperative frozen biopsy was performed on every patient and the results were compared. The progress was monitored every 3 to 6 months for recurrence or struggles with rehabilitation. Results. There were 13 male and 14 female patients with an average age of 54.6. The average tumor size was 8.2 cm (1.1 cm∼31.6 cm). Excision was performed using a wide excision. All 27 individuals were initially diagnosed as intramuscular lipoma; however, 1 of the patients was rediagnosed as liposarcoma in the final checkup. The patients had an average of 3 years and 1 month of follow-up and did not suffer recurrences. Conclusion. Thus, it is essential that a frozen biopsy is performed during the surgery in order to identify its malignancy. And a wide excision like malignant tumor operation is a principle of treatment.

Treatment of axillary osmidrosis with the use of Versajet

Axillary osmidrosis is a distressing problem. Since the secretion from apocrine glands is believed to be responsible for malodour, many treatment modalities have been developed to remove the glands. Local surgery with the excision of the apocrine glands has been proved to be most effective. We introduce the treatment of axillary osmidrosis, using Versajet (Versajet hydrosurgery system, Smith & Nephew, Memphis, TN, USA). From October 2010 to February 2012, 31 patients (21 females and 10 males) whose age ranged from 12 to 63 years were treated. All patients were followed up for 13.1 months on average. Thirty patients were very satisfied and recommended this procedure and one patient was satisfied with the result. We experienced one haematoma and one wound dehiscence. Excision of glands, using Versajet, makes the operation a simple and efficient procedure. Moreover, precise and even debridement reduces complications by preserving the skin flap and subdermal plexus.

Transareolar-perinipple (areolar omega) zigzag incision for augmentation mammaplasty.

Background: Optimal augmentation mammaplasty results not only from proper implant size and breast shape, but also from the minimization of postoperative scarring, especially in patients prone to hypertrophic scars. In this context, the authors present a transareolar-perinipple (areolar omega) zigzag approach. Methods: Between March of 2003 and June of 2012, a total of 613 patients underwent augmentation mammaplasty using a transareolar-perinipple incision. Among them, 45 patients received a classic (straight line) transareolar-perinipple incision, whereas 568 patients received a modified zigzag transareolar-perinipple incision. Results: Patients’ ages ranged from 21 to 60 years. Areola size varied from 2.3 to 4.5 cm in diameter. Follow-up duration ranged from 1 to 10 years, with an average of 2 years 7 months. Postoperative complications included capsular contracture, which occurred in 16 patients (2.6 percent). Nine patients (1.5 percent) had Baker class II and seven patients (1.1 percent) had Baker class III capsular contracture. Mild inferior displacement of the implant occurred in four patients (0.6 percent). The prevalence of areolar distortion was 3.4 percent. Nipple hypesthesia was found in approximately 70 percent of the patients, which returned to normal after 2 to 3 months. Based on third-party observers, 74.7 percent of patients who received zigzag transareolar-perinipple incision had excellent to good scarring results. Conclusions: The transareolar-perinipple (areolar omega) zigzag incision resulted in satisfactory postoperative scarring and surgical results in Asian patients. This method increases the opening of the areolar incision and can be performed in patients with small (<3.5 cm) areolas. This approach can be an alternative in patients who are prone to hypertrophic scarring. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.