Background Finding a material that supports bone regeneration is the concern for many investigators. We supposed that a composite scaffold of poly(ε) caprolactone and β-tricalcium phosphate (PCL-TCP) would entail desirable characteristics... more
Background Finding a material that supports bone regeneration is the concern for many investigators. We supposed that a composite scaffold of poly(ε) caprolactone and β-tricalcium phosphate (PCL-TCP) would entail desirable characteristics of biocompatibility, bioresorbability, rigidity, and osteoconductivity for a proper guided bone regeneration. Furthermore, the incorporation of mesenchymal stem cells (MSCs) and platelet-rich plasma (PRP) would boost the bone regeneration. We conducted this study to evaluate the bone regeneration capacity of PCL-TCP scaffold that is loaded with MSCs and PRP. Materials and methods Five miniature pigs received 6 implants in 6 created-mandibular bony defects in the right and left lower premolar areas. The bony defects were managed according to the following three groups: the PCL-TCP scaffold loaded with MSCs and PRP (MSCs+PRP+PCL-TCP) group (n = 10), PCL-TCP scaffold loaded with PRP (PRP+PCL-TCP) group (n = 10), and PCL-TCP scaffold group (n = 10). Af...
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Research Interests: Engineering and Vibration
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Research Interests: Biology and Urtica dioica
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Melanocytes in hair are located around dermal papilla cells at the tip of the hair follicle. In this study, we examined the melanogenesis of a three-dimensional (3D) hair dermal papilla model treated with natural extracts and... more
Melanocytes in hair are located around dermal papilla cells at the tip of the hair follicle. In this study, we examined the melanogenesis of a three-dimensional (3D) hair dermal papilla model treated with natural extracts and electromagnetic fields (EMFs). The 3D model involved dermal papilla-like tissue (DPLT), an aggregation of a mixture of dermal papilla cells, and melanocytes in microwells. Rice bran extract (RBE), an EMF, and RBE/EMF were applied to different DPLT groups. The LDH assay indicated no cell stress in all experimental groups, and detection of tyrosinase activity demonstrated high activity in the RBE/EMF group. Western blot analysis of the RBE, EMF, and RBE/EMF groups revealed increased MITF, TRP-1, and tyrosinase expression. In addition, the mRNA expression of ET-1, laminin, bFGF, β-catenin, MITF, and tyrosinase was increased in the RBE/EMF group, as demonstrated by RT-qPCR analysis. HMB45 and Fontana-Masson immunostaining showed that the RBE/EMF group had the highe...
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Electromagnetic fields (EMFs) are widely used in a number of cell therapies and bone disorder treatments, and nanomagnetic particles (NMPs) also promote cell activity. In this study, we investigated the synergistic effects of EMFs and... more
Electromagnetic fields (EMFs) are widely used in a number of cell therapies and bone disorder treatments, and nanomagnetic particles (NMPs) also promote cell activity. In this study, we investigated the synergistic effects of EMFs and NMPs on the osteogenesis of the human Saos‐2 osteoblast cell line and in a rat calvarial defect model. The Saos‐2 cells and critical‐size calvarial defects of the rats were exposed to EMF (1 mT, 45 Hz, 8 h/day) with or without Fe3O4 NMPs. Biocompatibility was evaluated with MTT (3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide) and LDH (lactate dehydrogenase) assays. This analysis showed that NMP and EMF did not induce cell toxicity. Quantitative reverse‐transcription polymerase chain reaction indicated that the osteogenesis‐related markers were highly expressed in the NMP‐incorporated Saos‐2 cells after exposure to EMF. Also, the expression of gene‐encoding proteins involved in calcium channels was activated and the calcium concentration o...
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Abstract This study compared the topography of different titanium surface structures (TiO2 nanotube and grain) with similar elemental compositions (TiO2 and fluorine [F]) on the Ti surface. High magnification indicated that the surfaces... more
Abstract This study compared the topography of different titanium surface structures (TiO2 nanotube and grain) with similar elemental compositions (TiO2 and fluorine [F]) on the Ti surface. High magnification indicated that the surfaces of the control and etching groups were similar to each other in a flat, smooth form. The group anodized for 1 h was observed with TiO2 nanotubes organized very neatly and regularly. In the group anodized for 30 min after etching, uneven wave and nanopore structures were observed. In addition, MTT assay showed that the F of the surface did not adversely affect cell viability, and the initial cell adhesion was increased in the 2.8% F‐incorporated TiO2 nanograin. At the edge of adherent cells, filopodia were observed in spreading form on the surfaces of the anodizing and two‐step processing groups, and they were observed in a branch shape in the control and etching groups. Moreover, cell adhesion molecule and osteogenesis marker expression was increased at the F‐incorporated TiO2 nanostructure. In addition, it was found that the expression of p‐extracellular signal‐regulated kinase (ERK) and p‐cAMP response element‐binding protein (CREB) increased in the TiO2 nanograin with the nanopore surface compared to the micro rough and nanotube surfaces relative to the osteogenic‐related gene expression patterns. As a result, this study confirmed that the topographic structure of the surface is more affected by osteogenic differentiation than the pore size and that differentiation by specific surface composition components is by CREB. Thus, the synergy effect of osteogenic differentiation was confirmed by the simultaneous activation of CREB/ERK.
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Mechanical/physical stimulations modulate tissue metabolism, and this process involves multiple cellular mechanisms, including the secretion of growth factors and the activation of mechano-physically sensitive kinases. Cells and tissue... more
Mechanical/physical stimulations modulate tissue metabolism, and this process involves multiple cellular mechanisms, including the secretion of growth factors and the activation of mechano-physically sensitive kinases. Cells and tissue can be modulated through specific vibration-induced changes in cell activity, which depend on the vibration frequency and occur via differential gene expression. However, there are few reports about the effects of medium-magnitude (1.12 g) sonic vibration on the osteogenic differentiation of human dental pulp stem cells (HDPSCs). In this study, we investigated whether medium-magnitude (1.12 g) sonic vibration with a frequency of 30, 45, or 100 Hz could affect the osteogenic differentiation of HDPSCs. Their cell morphology changed to a cuboidal shape at 45 Hz and 100 Hz, but the cells in the other groups were elongated. FACS analysis showed decreased CD 73, CD 90, and CD 105 expression at 45 Hz and 100 Hz. Additionally, the proportions of cells in the ...
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The purpose of the present study is to evaluate the effect of rice bran ash mineral extract (RBM) on pigmentation in zebrafish (Danio rerio). Melanin has the ability to block ultraviolet (UV) radiation and scavenge free oxygen radicals,... more
The purpose of the present study is to evaluate the effect of rice bran ash mineral extract (RBM) on pigmentation in zebrafish (Danio rerio). Melanin has the ability to block ultraviolet (UV) radiation and scavenge free oxygen radicals, thus protecting the skin from their harmful effects. Agents that increase melanin synthesis in melanocytes may reduce the risk of photodamage and skin cancer. The present study investigates the effect of RBM on pigmentation in zebrafish and the underlying mechanism. RBM was found to significantly increase the expression of microphthalmia-associated transcription factor (MITF), a key transcription factor involved in melanin production. RBM also suppressed the phosphorylation of extracellular signal-regulated kinase (ERK), which negatively regulates zebrafish pigmentation. Together, these results suggest that RBM promotes melanin biosynthesis in zebrafish.
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Melanogenesis is a biological process resulting in the production of melanin pigment, which plays an important role in the prevention of sun-induced skin injury, and determines hair and skin color. So, a wide variety of approaches have... more
Melanogenesis is a biological process resulting in the production of melanin pigment, which plays an important role in the prevention of sun-induced skin injury, and determines hair and skin color. So, a wide variety of approaches have been proposed to increase the synthesis of melanin. This study evaluated the effects of pulsed electromagnetic fields (PEMFs) on the pigmentation of zebrafish () in vivo. We stimulated pigmentation in zebrafish by using specific frequencies and intensities of PEMFs. This study focuses on pigmentation using PEMFs, and finds that PEMFs, at an optimal intensity and frequency, upregulate pigmentation by the stimulated expression of tyrosinase-related protein 1 (TRP1), dopachrome tautomerase (DCT) through extracellular signal-regulated kinase(ERK) phosphorylation, and p38 phosphorylation signaling pathways in zebrafish. These results suggest that PEMFs, at an optimal intensity and frequency, are a useful tool in treating gray hair, with reduced melanin syn...
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Purpose. The purpose of this study was to determine whether crush injured rat sciatic nerve could be benefit from pulsed electromagnetic field (PEMF) combined with human dental pulp stromal cells (hDPSCs), with FK506 (Tacrolimus) for... more
Purpose. The purpose of this study was to determine whether crush injured rat sciatic nerve could be benefit from pulsed electromagnetic field (PEMF) combined with human dental pulp stromal cells (hDPSCs), with FK506 (Tacrolimus) for immune suppression and neuropromotion. Materials and Methods. Male Sprague-Dawley rats (200-250 g, 6 week old) were distributed into 6 groups (n = 18 each): control, PEMF, FK506, PEMF + hDPSCs, PEMF + FK506, and PEMF + hDPSCs + FK506 groups. hDPSCs (cell = 1 × 106/10 μl/rat) were injected at the crush site immediate after injury. FK506 was administered 3 weeks in FK506 group (0.5 mg/kg/d) while pre-op 1 d and post-op 7 d in PEMF + FK506 and PEMF + hDPSCs + FK506 group; cell tracking was done with PKH26-labeled hDPSCs (cell = 1 × 106/10 μl/rat). The rats were follow-up for 3 weeks. Results. PEMF + FK506 and PEMF + hDPSCs + FK506 group showed a sharp increase in sciatic function index (SFI), axon counts, densities, and labeled neurons in dorsal root ganglia (DRG) than control at 3 weeks. Other three treatment groups also showed higher axon counts, densities, and labeled neurons than control. Higher axon counts and densities were found in PEMF + FK506 and PEMF + hDPSCs + FK506 groups comparing with PEMF group. Brain-derived neurotrophic factor (BDNF) mRNA expression pattern in nerve segment and DRG was almost same. Higher expression level in all the treatment groups was discovered in the follow-up period, but there was no significant difference. Conclusions. All treatment groups can improve regeneration of neurons following crushed injury, PEMF + FK506 and PEMF + hDPSCs + FK506 groups showed higher regeneration ability than other three groups. FK506 plays an important role during hDPSCs transplantation.
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MethodS: The silk scaffold was constructed using a weaving machine and dry-coated with collagen-hyaluronan (HA), whereas the composite silk scaffold was made by covering a silk scaffold with a lyophilized collagen-HA substrate. We... more
MethodS: The silk scaffold was constructed using a weaving machine and dry-coated with collagen-hyaluronan (HA), whereas the composite silk scaffold was made by covering a silk scaffold with a lyophilized collagen-HA substrate. We implanted the tendon prostheses into Achilles tendon defects in 16 white New Zealand rabbits. We established the following three experimental groups based on the replacement substitutes used: group I (silk scaffold alone); group II (composite silk scaffold); and group III (composite silk scaffold ensheathed in a human amniotic membrane). Implants were harvested 2, 8, and 12 weeks post-implantation. Histological examinations were conducted using hematoxylin-eosin, Masson’s trichrome, and by performing immunohistochemical staining for CD34. Tenocytes were cultured in vitro to compare cell populations in the three groups.
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Odontoblasts produce proteins that form the dentinal extracellular matrix, which can protect the dental pulp from external stimuli and is required for tooth regeneration. This study showed that a pulsed electromagnetic field (PEMF) can... more
Odontoblasts produce proteins that form the dentinal extracellular matrix, which can protect the dental pulp from external stimuli and is required for tooth regeneration. This study showed that a pulsed electromagnetic field (PEMF) can regulate cell metabolism and induce cell differentiation. This study determined the frequency of PEMF that is effective for odontoblast differentiation. Human dental pulp stem cells (hDPSCs) were cultured in odontoblast differentiation medium containing dexamethasone, BMP2, TGF-β1, and FGF-2, and then exposed to 10 mT intensity of PEMF at 40, 60, 70, and 150 Hz for 15 min/day. The MTT assay, LDH assay, flow cytometry, protein and gene expression, and immunofluorescence were performed to check if hDPSCs differentiated into odontoblast-like cells. The hDPSCs showed frequency-dependent differences in protein and gene expression. The mesenchymal stem cell markers were reduced to a greater extent at 60 and 70 Hz than at other frequencies, and odontoblast-r...
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Research Interests: Biology and Hair Follicle
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Research Interests: Psychology and Scalp
In this study, we used proteomics to investigate the effects of sonic vibration (SV) on mesenchymal stem cells derived from human umbilical cords (hUC-MSCs) during neural differentiation to understand how SV enhances neural... more
In this study, we used proteomics to investigate the effects of sonic vibration (SV) on mesenchymal stem cells derived from human umbilical cords (hUC-MSCs) during neural differentiation to understand how SV enhances neural differentiation of hUC-MSCs. We investigated the levels of gene and protein related to neural differentiation after 3 or 5 days in a group treated with 40-Hz SV. In addition, protein expression patterns were compared between the control and the 40-Hz SV-treated hUC-MSC groups via a proteomic approach. Among these proteins, calponin3 (CNN3) was confirmed to have 299 % higher expression in the 40-Hz SV stimulated hUC-MSCs group than that in the control by Western blotting. Notably, overexpression of CNN3-GFP in Chinese hamster ovary (CHO)-K1 cells had positive effects on the stability and reorganization of F-actin compared with that in GFP-transfected cells. Moreover, CNN3 changed the morphology of the cells by making a neurite-like form. After being subjected to S...
Research Interests: Technology, Calcium, Vibration, Protein Stability, Biological Sciences, and 14 moreCell Differentiation, Humans, Animals, Ultrasonics, Neurons, Liquid Chromatography / Electrospray Ionization Mass Spectrometry, SYNAPSES, Reproducibility of Results, Calcium Binding Proteins, Umbilical Cord, Mesenchymal Stromal Cells, Gene Expression Regulation, CHO cells, and Cricetinae
The aim of this study was to estimate the mechanical properties and evaluate the biocompatibility of silk and PGA scaffolds as an artificial ligament to an ACL reconstruction. The scaffold for the artificial ligament was braided / knitted... more
The aim of this study was to estimate the mechanical properties and evaluate the biocompatibility of silk and PGA scaffolds as an artificial ligament to an ACL reconstruction. The scaffold for the artificial ligament was braided / knitted silk or PGA thread. The mechanical properties, cell growth, and subcutaneous tissue reactions were determined for both types of scaffolds. The breaking load of the PGA scaffold was double that of the sericin removed silk scaffold (SRSS). However, the initial attachment and growth of human ACL cells on the SRSS was superior to the PGA scaffold. In addition, the immune response was significantly higher on the PGA scaffold after 72 h (p<0.05) compared with the sericin removed silk scaffold by T lymphocyte and mononuclear cells (MNCs) in vitro cultures. In vivo, the ACL scaffold made from silk or PGA were implanted in the subcutaneous layer in rats and harvested 1 week later. A histological evaluation of the scaffolds explants revealed the presence ...
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ABSTRACT
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Human bone marrow-derived mesenchymal stem cells (hBM-MSCs) are widely used in a number of cell therapies and have osteogenic differentiation capacity. Exposure to electromagnetic fields (EMFs) increases the osteogenic differentiation of... more
Human bone marrow-derived mesenchymal stem cells (hBM-MSCs) are widely used in a number of cell therapies and have osteogenic differentiation capacity. Exposure to electromagnetic fields (EMFs) increases the osteogenic differentiation of hBM-MSCs. Nanomagnetic particles (MPs) also promote the differentiation potential of stem cells. In the present study, we investigated the effects of EMFs and MPs on the osteogenic differentiation of hBM-MSCs. hBM-MSCs were treated with 50 µg/ml of Fe3O4 MPs or exposed to a frequency of 45 Hz and an intensity of 1 mT EMF twice every 8 h per day for 7 days. MP incorporation, EMF exposure and MP incorporation with exposure to EMFs did not induce cytotoxic effects. A strong expression of osteogenic markers (osteocalcin, osteopontin and osteonectin) and von Kossa staining intensity was observed in the cells treated with MPs, the cells exposed to EMFs and in the cells treated with MPs and exposed to EMFs compared with the control group, as shown by immun...
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In order to increase biocompatibility, many dental implants have been studied by immobilization of biomolecules on biomaterials. We used l-3,4-dihydroxyphenylalanine (L-DOPA) as a biomolecule for surface-modified titanium. Water contact... more
In order to increase biocompatibility, many dental implants have been studied by immobilization of biomolecules on biomaterials. We used l-3,4-dihydroxyphenylalanine (L-DOPA) as a biomolecule for surface-modified titanium. Water contact angles of nontreated titanium discs (negative control), etched titanium discs (positive control), and titanium discs treated with L-DOPA following the etching process (experimental group) were 82.4 ± 5.7°, 67.1 ± 0.56°, and 44.15 ± 0.91°, respectively. Using atomic force microscopy images, we were able to find L-DOPA, which adhered to the titanium surface. The number of human bone marrow mesenchymal stem cells (BM-MSCs) in the experimental group was much higher than that of cells in any other group. Quantification values of amine groups in the positive control and experimental groups were approximately 3 and 7.5 µg, respectively. Therefore, findings from our research suggested the possibility of a causal link between increased L-DOPA content and cell...
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... [11] Daniels, JT, JKG Dart, SJ Tuft, and PT Khaw (2001) Corneal stem cells in review. Wound Rep. Reg. ... De-cember 10-13. Orlando, USA. [31] Park, JK, JI Ahn, IK Jang, JB Ju, JC Kim, KY Song, HG Lee, EK Yang, and ... Ophthalmol. 48:... more
... [11] Daniels, JT, JKG Dart, SJ Tuft, and PT Khaw (2001) Corneal stem cells in review. Wound Rep. Reg. ... De-cember 10-13. Orlando, USA. [31] Park, JK, JI Ahn, IK Jang, JB Ju, JC Kim, KY Song, HG Lee, EK Yang, and ... Ophthalmol. 48: 631-646. [34] Kahn, CR, E. Young, IH Lee ...