Sik Namgoong

Risk factors for major amputation in hospitalised diabetic foot patients

Diabetic foot ulcers are the main cause of non‐traumatic lower extremity amputation. The objective of this study was to evaluate the risk factors for major amputation in diabetic foot patients. Eight hundred and sixty diabetic patients were admitted to the diabetic wound centre of the Korea University Guro Hospital for foot ulcers between January 2010 and December 2013. Among them, 837 patients were successfully monitored until complete healing. Ulcers in 809 patients (96·7%) healed without major amputation and those in 28 patients (3·3%) healed with major amputation. Data of 88 potential risk factors including demographics, ulcer condition, vascularity, bioburden, neurology and serology were collected from patients in the two groups and compared. Among the 88 potential risk factors, statistically significant differences between the two groups were observed in 26 risk factors. In the univariate analysis, which was carried out for these 26 risk factors, statistically significant differences were observed in 22 risk factors. In a stepwise multiple logistic analysis, six of the 22 risk factors remained statistically significant. Multivariate‐adjusted odds ratios were 11·673 for ulcers penetrating into the bone, 8·683 for dialysis, 6·740 for gastrointestinal (GI) disorders, 6·158 for hind foot ulcers, 0·641 for haemoglobin levels and 1·007 for fasting blood sugar levels. The risk factors for major amputation in diabetic foot patients were bony invasions, dialysis, GI disorders, hind foot locations, low levels of haemoglobin and elevated fasting blood sugar levels.

Wound-healing potential of human umbilical cord blood-derived mesenchymal stromal cells in vitro--a pilot study.

BACKGROUND AIMS Our previous studies demonstrated that human bone marrow-derived mesenchymal stromal cells have great potential for wound healing. However, it is difficult to clinically utilize cultured stem cells. Recently, human umbilical cord blood-derived mesenchymal stromal cells (hUCB-MSCs) have been commercialized for cartilage repair as a first cell therapy product that uses allogeneic stem cells. Should hUCB-MSCs have a superior effect on wound healing as compared with fibroblasts, which are the main cell source in current cell therapy products for wound healing, they may possibly replace fibroblasts. The purpose of this in vitro study was to compare the wound-healing activity of hUCB-MSCs with that of fibroblasts. METHODS This study was particularly designed to compare the effect of hUCB-MSCs on diabetic wound healing with those of allogeneic and autologous fibroblasts. Healthy (n = 5) and diabetic (n = 5) fibroblasts were used as the representatives of allogeneic and autologous fibroblasts for diabetic patients in the control group. Human UCB-MSCs (n = 5) were used in the experimental group. Cell proliferation, collagen synthesis and growth factor (basic fibroblast growth factor, vascular endothelial growth factor and transforming growth factor-β) production were compared among the three cell groups. RESULTS Human UCB-MSCs produced significantly higher amounts of vascular endothelial growth factor and basic fibroblast growth factor when compared with both fibroblast groups. Human UCB-MSCs were superior to diabetic fibroblasts but not to healthy fibroblasts in collagen synthesis. There were no significant differences in cell proliferation and transforming growth factor-β production. CONCLUSIONS Human UCB-MSCs may have greater capacity for diabetic wound healing than allogeneic or autologous fibroblasts, especially in angiogenesis.

Effects of Panax ginseng extract on human dermal fibroblast proliferation and collagen synthesis

Current studies of Panax ginseng (or Korean ginseng) have demonstrated that it has various biological effects, including angiogenesis, immunostimulation, antimicrobial and anti‐inflammatory effects. Therefore, we hypothesised that P. ginseng may also play an important role in wound healing. However, few studies have been conducted on the wound‐healing effects of P. ginseng. Thus, the purpose of this in vitro pilot study was to determine the effects of P. ginseng on the activities of fibroblasts, which are key wound‐healing cells. Cultured human dermal fibroblasts were treated with one of six concentrations of P. ginseng: 0, 1, 10 and 100 ng/ml and 1 and 10 µg/ml. Cell proliferation was determined 3 days post‐treatment using the 3‐(4, 5‐dimethylthiazol‐2‐yl)‐2, 5‐diphenyl tetrazolium bromide assay, and collagen synthesis was evaluated by the collagen type I carboxy‐terminal propeptide method. Cell proliferation levels and collagen synthesis were compared among the groups. The 10 ng/ml to 1 µg/ml P. ginseng treatments significantly increased cell proliferation, and the 1 ng/ml to 1 µg/ml concentrations significantly increased collagen synthesis. The maximum effects for both parameters were observed at 10 ng/ml. P. ginseng stimulated human dermal fibroblast proliferation and collagen synthesis at an optimal concentration of 10 ng/ml.

Alternative Choices for Anterolateral Thigh Flaps Lacking Suitable Perforators: A Systematic Review

Background The anterolateral thigh (ALT) flap has become a predominant option in the field of reconstruction. However, some difficulties in harvesting flap exist due to the anatomical variability of the perforators. Reports have provided solutions for unreliable perforators. Although numerous cases that showed successful conversion to tensor fasciae latae (TFL) flap or anteromedial thigh (AMT) flap have been reported in the literature, none fully addresses the reliability of the perforators that have been described to date. Therefore, we conducted a systematic literature review to compare the reliability of the TFL flap with that of the AMT flap when an ALT flap perforator is not suitable. Methods A systematic review of the MEDLINE, PubMed, and Cochrane Library electronic databases was performed to compare the characteristics of TFL and AMT flap perforators. Results A total of 13 articles were included for review. The mean number of TFL perforators varied from 1.41 to 3.17 per thigh. The mean number of AMT perforators was between 0.59 and 1.3 per thigh. The cumulative assessment of the clinical and anatomical studies showed 456 perforators in 180 TFL flaps (mean, 2.53) and 145 perforators in 162 AMT flaps (mean, 0.90). The mean pedicle length of the TFL and AMT flaps ranged from 7.0 to 9.59 cm and from 7.4 to 11.0 cm, respectively. The mean perforator diameter was similar in both flaps. Conclusion Currently available literature suggests that the TFL flap may be a more reliable alternative when adequate perforators are not found for ALT flap harvest.

Optimal Viscosity and Particle Shape of Hyaluronic Acid Filler as a Scaffold for Human Fibroblasts.

AbstractThe authors previously reported that cultured human fibroblasts suspended in a hyaluronic acid filler can produce human dermal matrices with extended in vivo stability in animal and clinical studies. The present study was undertaken to determine the optimal viscosity and particle shape of hyaluronic acid filler as a scaffold for cultured human dermal fibroblasts to enhance the maximal viability of injected cells. The fibroblasts were suspended in either 1 of 3 hyaluronic acid viscosities at 2 different particle shapes. The viscosities used in this study were low (600,000–800,000 centipoises), moderate (2,000,000–4,000,000 centipoises), and high (8,000,000–12,000,000 centipoises). The particle shape was evaluated by testing round and irregular shapes. The fibroblast mixed bioimplants were injected into the back of individual athymic nude mice. The levels of type I collagen were measured using fluorescent-activated cell sorting (FACS) and immunohistochemical staining at 16 weeks after the injections. Results of FACS demonstrated that the mean cell ratio with human collagens in the moderate viscosity group was greater than those of control, low, and high viscosity groups. An immunohistochemical study showed similar results. The moderate viscosity group demonstrated the highest positive staining of human collagens. However, there were no significant differences between groups of irregular and round shape particles. A hyaluronic acid bioimplant with moderate viscosity is superior to that with low or high viscosity in the viability for human fibroblasts. However, the particle shape does not influence the viability of the fibroblasts.

Comparison of perfusion values after percutaneous transluminal angioplasty according to the severity of ischaemia in the diabetic foot

Percutaneous transluminal angioplasty (PTA) is now more frequently used to improve tissue perfusion in ischemic diabetic feet. However, there are concerns about its feasibility and effectiveness in severely ischaemic feet. This study aimed to compare the perfusion values after PTA according to the ischaemic degree of diabetic feet. This study included 133 ischaemic diabetic feet. The foot transcutaneous oxygen pressure (TcPO2) and toe pressure were measured before the procedure and every second postoperative week for 6 weeks. The patients were divided into three groups according to ischaemic severity on the basis of TcPO2 and toe pressures. In the “severely ischaemic” group, the TcPO2 increased from 7.5 ± 4.9 to 40.3 ± 11.3 mm Hg (5.4‐fold) 6 weeks after the PTA (P < 0.001). The toe pressure increased from 8.5 ± 8.8 to 42.2 ± 19.3 mm Hg (5.0‐fold, P < 0.001). In the “mild” group, the TcPO2 increased from 35.4 ± 2.5 to 41.8 ± 12.4 mm Hg (1.2‐fold, P = 0.003), and the toe pressure increased from 45.7 ± 12.3 to 54.3 ± 31.3 mm Hg (1.2‐fold, P > 0.05). Results of the “intermediate” group were in between. The most severely ischaemic group had the most dramatic increase of tissue perfusion after PTA. As such, PTA can be an effective method for increasing tissue perfusion even in the severely ischaemic diabetic feet.

Status of Wound Management in Korea

In spite of a period of intense economic, social, and political hardship following the Korean War, the Republic of Korea has made great strides in economic growth over the past half century, and also remarkable progress in the medical field. However, wound research has been slow to take off in South Korea. Meanwhile, as is the case in many countries in Western Europe and North America, South Korea is seeing a steady increase in its aged population. The growth in the geriatric population has in turn brought on more cases of chronic wounds. Though South Korea only began to recognize the importance of wound management in the early 2000s, it was fortunate enough to have sophisticated related industries, such as biotechnology and information technology, and brilliant, industrious, and eager wound researchers, contributing to rapid development of the field. The country has particular strengths in research for innovative cell‐based treatments and products for managing wounds. Notwithstanding government policy ill‐equipped to sufficiently support such advancement, better communication between experts and public officials will no doubt bring forth even more achievements in this very promising field. It is in this context that this article aims to summarize current wound management practices, research, training, product development, and government policies regarding wound management in South Korea as of the year 2017.

Tracking and Increasing Viability of Topically Injected Fibroblasts Suspended in Hyaluronic Acid Filler.

AbstractA new injectable tissue-engineered soft tissue consisting of a mixture of hyaluronic acid (HA) filler and cultured human fibroblasts have been developed by the authors. To establish this method as a standard treatment, a further study was required to determine whether the injected fibroblasts could stay at the injected place or move to other sites. In addition, effective strategies were needed to increase viability of the injected fibroblasts. The purpose of this study was to track the injected fibroblasts and to determine the effect of adding prostaglandin E1 (PGE1) or vitamin C on the viability of fibroblasts.Human fibroblasts labeled with fluorescence dye were suspended in HA filler and injected into 4 sites on the back of nude mice. The injected bioimplants consisted of one of the 4 followings: HA filler without cells (HA group), fibroblasts suspended in HA filler (HA + FB group), PGE1-supplemented fibroblasts in HA filler (HA + FB + PGE1 group), and vitamin C-supplemented fibroblasts in HA filler (HA + FB + VC group). At 4 weeks after injection, locations and intensities of the fluorescence signals were evaluated using a live imaging system.The fluorescence signals of the fibroblast-containing groups were visible only at the injected sites without dispersing to other sites. The HA +FB + PGE1 group showed a significantly higher fluorescence signal than the HA + FB and the HA + FB +VC groups (P < 0.05, each). There was no statistical difference between the HA + FB and HA + FB +VC groups (P = 0.69).The results of the current study collectively suggest that injected fibroblasts suspended in HA filler stay at the injected place without moving to other sites. In addition, PGE1 treatment may increase the remaining rhodamine B isothiocynanate dye at the injected site of the human dermal fibroblasts.