Bommie F. Seo

The Stem Cell Potential and Multipotency of Human Adipose Tissue-Derived Stem Cells Vary by Cell Donor and Are Different from Those of Other Types of Stem Cells

Human adipose tissue-derived mesenchymal stem cells (AT-MSCs) from various sites are applied in tissue engineering and cell therapy. The condition of AT-MSCs depends on the donors age, body mass index (BMI), and gender. AT-MSCs from 66 human donors were analyzed, and the cells were sorted according to donor age (10-19 years: n = 1; 20-29 years: n = 5; 30-39 years: n = 12; 40-49 years: n = 22; 50-59 years: n = 12; 60-69 years: n = 9, and 70 years or older: n = 5), BMI (under 25, 25-30, and over 30), and gender (19 males and 48 females). Additionally, AT-MSCs were compared to bone marrow MSCs and chorionic tissue-derived MSCs. We measured the MSC yield, growth rate, colony-forming units, multipotency, and surface antigens. AT-MSC proliferation was greater in cells isolated from individuals aged less than 30 years compared to the proliferation of AT-MSCs from those over 50 years old. BMI was correlated with osteogenic differentiation potency; increased BMI enhanced osteogenesis. Adipogenic differentiation was more strongly induced in cells isolated from donors aged less than 30 years compared to those isolated from other age groups. Also, a BMI above 30 was associated with enhanced adipogenic differentiation compared to cells isolated from individuals with a BMI below 25. Bone marrow MSCs were strongly induced to differentiate along both osteogenic and adipogenic lineages, whereas AT-MSCs predominantly differentiated into the chondrogenic lineage. Therefore, the type of regeneration required and variations among potential donors must be carefully considered when selecting MSCs for use in applied tissue engineering or cell therapy.

Models of Abnormal Scarring

Keloids and hypertrophic scars are thick, raised dermal scars, caused by derailing of the normal scarring process. Extensive research on such abnormal scarring has been done; however, these being refractory disorders specific to humans, it has been difficult to establish a universal animal model. A wide variety of animal models have been used. These include the athymic mouse, rats, rabbits, and pigs. Although these models have provided valuable insight into abnormal scarring, there is currently still no ideal model. This paper reviews the models that have been developed.

Use of split thickness plantar skin grafts in the treatment of hyperpigmented skin-grafted fingers and palms in previously burned patients

Palmar and finger burns are often seen in children, and are usually as a result of contact burns. Some patients with deep hand burns are treated with full-thickness or split-thickness skin grafts. Skin graft is commonly used for hand reconstruction. However, the grafted skin would be more pigmented than the adjacent skin and different from skin texture. 19 patients who showed hyperpigmentation after skin graft of finger and palm were treated. They all were injured by hand burns. We performed mechanical dermabrasion of the hyperpigmentation scar and application of a split thickness skin harvested from medial aspect of plantar of foot. Patients were asked about their level of satisfaction with the procedure and scar appearance was assessed using a five-point Likert scale. Also scar appearances were assessed using a Vancouver Scar Scale (VSS). The grafts were completely taken in all 19 patients. The color of the graft became similar to adjacent tissue. 15 patients were very satisfied, and four patients were relatively satisfied. The average score of the patients postoperative appearance improvement was 4.5 (improved to significantly improved postoperative appearance). Average VSS score was improved from 9.53 to 2.53. There was no hypertrophic scar on plantar donor site. The technique of the split-thickness plantar skin graft after mechanical dermabrasion is simple and provided good results in both color and texture for the patients who showed hyperpigmentation after grafting.

The Immunomodulatory Effects of Mesenchymal Stem Cells in Prevention or Treatment of Excessive Scars

Excessive scars, including keloids and hypertrophic scars, result from aberrations in the process of physiologic wound healing. An exaggerated inflammatory process is one of the main pathophysiological contributors. Scars may cause pain, and pruritis, limit joint mobility, and cause a range of cosmetic deformities that affect the patients quality of life. Extensive research has been done on hypertrophic scar and keloid formation that has resulted in the plethora of treatment and prevention methods practiced today. Mesenchymal stem cells, among their multifunctional roles, are known regulators of inflammation and have been receiving attention as a major candidate for cell therapy to treat or prevent excessive scars. This paper extensively reviews the body of research examining the mechanism and potential of stem cell therapy in the treatment of excessive scars.

Efficacy of Biodegradable Synthetic Polyurethane Foam for Packing Nasal Bone Fractures

Background Nasal bone fracture is the most common traumatic disease among facial bone fractures. General treatment of this trauma is closed reduction, followed by intranasal packing. Vaseline or Furacin roll gauze, and Merocel are commonly used packing materials, but the pain produced while removing the packing is fearful for the patients. To compensate for this shortcoming, there has been an increased use of biodegradable synthetic polyurethane foam (SPF) recently. We performed a retrospective review to analyze the effectiveness of SPF after the closed reduction of nasal bone fracture. Patients and Methods A retrospective review was conducted in 109 patients who underwent closed reduction for pure nasal bone fracture. One group was packed with Furacin roll gauze and the other was packed with SPF. Postoperative pain, hemostatic effect, supporting ability on the fractured segment, and healing of the injured nasal mucosa were compared between the 2 groups. Results A total of 109 patients were reviewed, with 61 patients packed with Furacin roll gauze (group A) and 48 patients packed with SPF (group B). Between the 2 groups, only visual analogue scale of pain at postoperative fourth day was statistically low in group B (P = 0.045) with other parameters showing no statistical difference. Discussion Nasal packing after closed reduction of nasal bone fractures support the reduced fractured bony segment and also has the main role on hemostasis and healing of mucosal injury. Removal of the packing is painful and fearful to the patients. SPF as nasal packing material provides superior outcome in terms of pain and satisfaction and, at the same time, is not inferior to the conventional packing materials with regard to bleeding control, mucosal wound healing, toxicity, and stability of reduced fracture segment.

The effects of human keratinocyte coculture on human adipose-derived stem cells.

The potential for adipose‐derived stem cells to differentiate into keratinocyte‐like cells has recently been receiving attention, stemming from the hypothesis that a bioengineered skin may be manufactured from these readily available mesenchymal stem cells. This study was conducted to evaluate the influence of human keratinocyte non‐contact coculture on hADSCs. Human epidermal keratinocytes and hADSCs obtained by lipoaspiration were cultured in keratinogenic growth media, which were divided into the following groups: human adipose‐derived stem cell (hADSC) monoculture, non‐contact coculture of hADSCs and human keratinocytes and keratinocyte monoculture. Cell proliferation was assessed, and keratogenicity was analysed through immunocytochemistry and polymerase chain reaction of early, intermediate and late keratogenic markers. hADSCs cocultured with keratinocytes displayed enhanced proliferation compared with the monoculture group. After a 7‐day coculture period, immunohistochemistry and polymerase chain reaction findings revealed the presence of specific keratinocyte markers in the coculture group. This study demonstrates that hADSCs cocultured with keratinocytes have the capacity to transdifferentiate into keratinocyte lineage cells, and suggests that adipose tissue may be a source of keratinocytes that may further be used in structuring the bioengineered skin.

Lymph node compression of the lesser occipital nerve: A cause of migraine

Recent investigation has focussed on the concept of peripherally triggered migraine headaches caused by compression, irritation or entrapment of the sensory nerves in the head and neck. We report a case of a 52-year-old male suffering from an occipitoparietal migraine that presented with a mass in the right occipital area. The mass was found in the deep layer of subcutaneous tissue just over the semispinalis muscle, sitting on top of the lesser occipital nerve, which was preserved through delicate dissection using loupe magnification. Histopathological findings of the mass reported benign, reactive hyperplasia of the lymph node. After removal of the mass, the patient reported complete resolution of headaches. Sensation of the scalp was not altered. This is the first report of a case of hyperplastic lymph node causing migraine through physical compression of a peripheral nerve.

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.

A Huge Morel-Lavallée Lesion Treated Using a Quilting Suture Method: A Case Report and Review of the Literature

The Morel-Lavallée lesion is a collection of serous fluid that develops after closed degloving injuries and after surgical procedures particularly in the pelvis and abdomen. It is a persistent seroma and is usually resistant to conservative methods of treatment such as percutaneous drainage and compression. Various methods of curative treatment have been reported in the literature, such as application of fibrin sealant, doxycycline, or alcohol sclerodhesis. We present a case of a huge recurrent Morel-Lavallée lesion in the lower back and buttock region that was treated with quilting sutures, fibrin sealant, and compression, with a review of the literature.