Kyung Mi Shim

Effect of Korean Red Ginseng Extract in a Steroid-induced Polycystic Ovary Murine Model

Experimental induction of polycystic ovary (PCO) in rodent resembling some aspects of human PCO syndrome was produced using the long-acting compound estradiol valerate (EV). Our previous study on the role of Korean red ginseng total saponins in a steroid-induced PCO rat model demonstrated that electro-acupuncture modulates nerve growth factor (NGF) concentration in the ovaries. In fact, the involvement of a neurogenic component in the pathology of PCO-related ovarian dysfunction is preceded by an increase in sympathetic outflow to the ovaries. In the present study, we tested the hypothesis that Korean red ginseng extract (KRGE) administration modulates sympathetic nerve activity in PCO-induced rats. This was done by analyzing NGF protein and NGF mRNA expression involved in the pathophysiological process underlying steroid-induced PCO. EV injection resulted in significantly higher ovarian NGF protein and NGF mRNA expression in PCO-induced rats compared to control rats, and PCO ovaries were counteracted by KRGE administration with significantly lower expression of NGF protein and NGF mRNA compared to EV treated ovaries. These results indicate that EV modulates the neurotrophic state of the ovaries, which may be a component of the pathological process by which EV induces cyst formation and anovulation in rodents.

Effect of Porcine Cancellous Bones on Regeneration in Rats with Calvarial Defect

The purpose of this study was to evaluate the effect of porcine cancellous bone as a scaffold in a rat calvarial defect model. Critical-sized defects were created in 30 male Sprague-Dawley rats. The animals were divided into critical defect (CD, n=10), -tricalcium phosphate (TCP) graft (BT, n=10) and porcine cancellous bone graft (PCB, n=10) groups. Each defect was filled with -TCP mixed with fibrin glue or porcine cancellous bone powder mixed with fibrin glue. In the CD group, the defect was left empty. All rats were sacrificed at 8 weeks after bone graft surgery, and bone formation was evaluated by gross observation, plain radiography, micro-computed tomography scanning and histological evaluation. Repair of bone defect was the least in the CD group, and significant new bone formation was observed in the PCB group. Grafting of porcine cancellous bone was more efficient for regenerating new bone than grafting -TCP.

Osteogenic effect of low‐temperature‐heated porcine bone particles in a rat calvarial defect model

The current study was designed to investigate the chemical and physical properties of porcine-derived xenografts of different crystallinity (low and high) and to evaluate their osteogenic potential. Porcine femur bone underwent a heat treatment process at 400°C (P400) and 1200°C (P1200) and was then milled into particles of 1 mm or less. In X-ray diffraction, P400 exhibited a low crystallinity compared with that of P1200, as indicated by the relatively wide diffraction peaks. Brunauer-Emmett-Teller analysis revealed that P400 also had a wider surface area than P1200. In micro-CT scan analysis of specimens in a rat calvarial defect model, bone mineral density of the P400 group was significantly higher than that of the P1200 group (p < 0.01). New bone formation was also remarkably higher at 8 weeks in the P400 group, which showed more new osteocytes in the lacuna compared with the P1200 group. In this study, low crystalline bone particles were obtained at low processing temperature (at temperature of 400°C) and achieved superior new bone formation compared with the high crystalline bone particles created at a higher process temperature (1200°C). It can be concluded that lower process temperature bone particles might provide a more effective graft material for enhancing bone formation.

Effects of CS682, a Fermentation Product of Korean Soil Bacteria, on Growth Performance in Chickens and Pigs

Antibiotics in veterinary medicine have been used to treat disease, promote growth rate and improve feed efficiency. However, alternative sources are needed because of of bacterial resistance to antibiotics and residues of antibiotics. The present study was carried out to evaluate the effect of CS682, a fermentation product of Korean soil bacteria, on safety, growth rate an d feed efficiency, and to evaluate its value as an alternative for antibiotics used as a feed additive. Two dosages of CS682 (0.1% and 1%) were fed to chickens for 28 days. The results showed that, when compared to chickens in the control group, growth and feed efficiency was improved. Also, mortality, hematology, general clinical signs and necropsy were examined. Chickens in the treatment groups showed no adverse effects. A total of 72 weaning pigs were used to confirm the effects of CS682 at one dose level (0.1%) regarding feed efficiency. Supplementation with 0.1% CS682 also resulted in improved weight gain and feed efficiency ratio. Based on these results, CS682 may be effective in improv ing feed efficiency safely as a feed additive.

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-1β 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.

Effects of PMMA and Cross-Linked Dextran Filler for Soft Tissue Augmentation in Rats

This study was conducted for evaluation of the ability to maintain efficacy and biocompatibility of cross-linked dextran in hydroxypropyl methylcellulose (DiHM) and cross-linked dextran mixed with PMMA in hydroxypropyl methylcellulose (PDiHM), compared with hyaluronic acid (HA) filler. Saline and HA solution was administered in the negative and positive control groups, and DiHM and PDiHM were administered in the test groups (n = 10 in each group). The site of cranial subcutaneous injection was the mid-point of the interpupillary line, and the site of intraoral submucosal injection was the ridge crest 2 mm below the cervical line of the mandibular left incisor. Before and immediately after filler injection, intraoral photos and lateral cephalometric radiographs were taken for analysis and comparison of the effect of the filler on the injection sites. The filler injected areas were converted into sequential size changes (%) of the baseline. Histomorphologic examination was performed after 12 weeks. The smallest value in the filler injected area was observed during the experimental period in the normal saline group (p < 0.001), which was almost absorbed at 4 weeks (7.19% ± 12.72%). The HA group exhibited a steady decrease in sequential size and showed a lower value than the DiHM and PDiHM groups (saline < HA < DHiM, PDHiM, p < 0.001). DiHM and PDiHM tended to increase for the first 4 weeks and later decreased until 12 weeks. In this study on DiHM and PDiHM, there was no histological abnormality in cranial skin and oral mucosa. DiHM and PDiHM filler materials with injection system provide an excellent alternative surgical method for use in oral and craniofacial fields.

Manufacture of duck-beak bone particles with gamma-ray irradiation for bone graft

There is a growing interest in bone graft materials for enhancing bone formation. We have focused on bone xenograft using animal by-products. Among animal by-products, the duck beak was specifically used in this study for manufacture of bone graft particles. Harvested duck-beak bone was defatted, deproteinized, and then heat-treated at 350ΰC. Subsequently, it was ground to ≤ 53 μm in a ceramic ball mill and irradiated with gamma rays at radiation doses of 0, 15, 20, 25, and 40 kGy. =Field emission scanning electron microscope (FE-SEM), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), thermogravimetric analysis (TGA) and the MTT assay were performed to investigate the effects of gamma-ray irradiation on the properties of duck-beak bone particles. Surface morphology of duck-beak bone particles by FE-SEM showed that bone particles had various sizes and similar surfaces between the 0, 15, 20, 25, and 40 kGy groups. The ATR-FTIR spectrum of all groups showed the characteristic peaks of PO43− and CO32− functional groups. Weight losses were observed and there was no significant difference in the curves depending on the radiation doses, by TGA analyses. The viabilities of human mesenchymal stem cells were 90–100% in all groups in the MTT assay. Based on our results, sterilization by gamma-ray irradiation < 40 kGy had no effect on the physical and surface properties of duck-beak bone particles. Therefore, this study showed that gamma-ray irradiation can be effectively used for the sterilization of duck-beak bone derived xenografts.

Normal Lung Ventilation/Perfusion Scintigraphy in Miniature Pigs

Miniature pigs are widely used in experiments related to pulmonary disease because of their similarities with humans. However, there are not enough data about normal lung function in miniature pigs. Thus, in this study, we investigated normal lung function in miniature pigs with lung ventilation/perfusion scintigraphy and evaluated the availability of this method. Three male miniature pigs weighing 30-35 kg were used. After general anesthesia, ventilation scintigraphy was performed with 100 MBq of -pertechnetate (), after which perfusion scintigraphy was performed with intravenous injection of -macro aggregated albumin (MAA). The functional contribution of the right lung was about 55%, and left lung was about 45%, similar to humans. Lung ventilation/perfusion scintigraphy was very useful in evaluating the normal lung function of miniature pigs because it was a non-invasive procedure (no tissue damage was involved), took a short time and was easy to perform. In conclusion, miniature pigs are similar to humans in functional contributions of the lung, and this method will be helpful in future pulmonary disease studies involving miniature pigs.