• Restorative Dentistry and Endodontics
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• v.42 no.4
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• pp.290-300
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• 2017

Objectives: This study investigated the removal efficacy and cytotoxicity of a newly developed calcium hydroxide paste (cleaniCal, Maruchi) using N-2-methyl-pyrrolidone (NMP) as a vehicle in comparison with ApexCal (Ivoclar Vivadent) and Calcipex II (Nishika), which use different vehicles such as polyethylene glycol and propylene glycol, respectively. Materials and Methods: Thirty maxillary premolars with oval-shaped canals were divided into 3 groups and the teeth were filled with one of the pastes. After removal of the paste, micro-computed tomographic (${\mu}$-CT) imaging was obtained to assess the volume of residual paste in the root canal of each tooth. The teeth were then split longitudinally and the area of the paste-coated surface was evaluated by stereomicroscopy. The cytotoxicity of each product was assessed using an agar overlay assay. The effect of each vehicle on cell viability was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The data were analyzed using one-way analysis of variance and Tukey's tests to detect any significance (p < 0.05). Results: In the ${\mu}$-CT and stereomicroscopic analysis, cleaniCal exhibited less remnants of medicament than ApexCal and Calcipex. cleaniCal showed a higher cytotoxicity than the other pastes in the agar overlay assay. Furthermore, NMP exhibited lower cell viability compared to the other vehicles. Conclusions: cleaniCal showed better removal efficacy compared to the other products. However, clinicians should be aware of the higher cytotoxicity of the NMP-based material and consider its possible adverse effects on periradicular tissue when it is overfilled.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.4
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• pp.863-870
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• 2008

The aim of this study was to investigate that Injinoryung-san-Ga-Samchilgun(IJORS) has an inhibitory effect on the development of liver fibrosis in rats. The influence of IJORS on liver stellate cell viability in rat was measured by the MTT assay, and proliferation was measured by the BrdU assay. The mRNA expression of procollagen type $1{\alpha}2$, ${\alpha}-SMA$, TIMP1, and TIMP2 all of which are associated with liver fibrosis, were analyzed by RT-PCR. The inhibitory effect of IJORS on procollagen production in hepatic stellate cell was examined using by enzyme immuno assay(procollagen Type 1 C-Peptide EIA). And after IJORS was orally administered to experimental rats with thioacetamide(TAA)-induced liver fibrosis for 4 weeks, the body weight, liver function test, complete blood and the change of portal pressure were measured. IJORS prevented hepatic stellate cell viability and proliferation in a dose-dependent manner. IJORS reduced the mRNA expression of procollagen type $1{\alpha}2$, ${\alpha}-SMA$ and TIMP1 and the production of procollagen protein. IJORS inhibited the increase of AST, ALT, WBC and portal pressure in rats administered by TAA. IJORS is considered to prevent liver fibrosis by inhibiting the activation of stellate cell and production of procollagen and prevent the progress of liver fibrosis by inhibiting the inflammation of liver tissue complicated in many liver disease.

• The Korean Journal of Physiology and Pharmacology
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• v.9 no.5
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• pp.283-289
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• 2005

Endothelium, particularly pulmonary endothelium, is predisposed to injury by reactive oxygen species (ROS) and their derivatives. Heme oxygenase (HO) has been demonstrated to provide cytoprotective effects in models of oxidant-induced cellular and tissue injuries. In the present study, we investigated the effects of YS 49 against oxidant [tert-butylhydroperoxide (TBH)]-induced injury using cultured sheep pulmonary artery endothelial cells (SPAECs). The viability of SPAECs was determined by quantifying reduction of a fluorogenic indicator Alamar blue. We found that TBH decreased cell viability in a timeand concentration-dependent manner. YS 49 concentration- and time-dependently increased HO-1 induction on SPAECs. As expected, YS 49 significantly decreased the TBH-induced cellular injury. In the presence of zinc protophorphyrin, HO-1 inhibitor, effect of YS 49 was significantly inhibited, indicating that HO-1 plays a protective role for YS 49. Furthermore, YS 49 showed free radical scavenging activity as evidenced by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and inhibition of lipid peroxidation. However, YS 49 did not inhibit apoptosis induced by lipopolysaccharide (LPS) in SPAECs. Taken together, HO-1 induction along with strong antioxidant action of YS 49 may be responsible for inhibition of TBH-induced injury in SPAECs.

• Nutrition Research and Practice
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• v.9 no.6
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• pp.592-598
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• 2015

BACKGROUND/OBJECTIVES: Increased mass of adipose tissue in obese persons is caused by excessive adipogenesis, which is elaborately controlled by an array of transcription factors. Inhibition of adipogenesis by diverse plant-derived substances has been explored. The aim of the current study was to examine the effects of the aqueous methanol extract of laver (Porphyra yezoensis) on adipogenesis and apoptosis in 3T3-L1 adipocytes and to investigate the mechanism underlying the effect of the laver extract. MATERIALS/METHODS: 3T3-L1 cells were treated with various concentrations of laver extract in differentiation medium. Lipid accumulation, expression of adipogenic proteins, including CCAAT enhancer-binding protein ${\alpha}$, peroxisome proliferator-activated receptor ${\gamma}$, fatty acid binding protein 4, and fatty acid synthase, cell viability, apoptosis, and the total content and the ratio of reduced to oxidized forms of glutathione (GSH/GSSG) were analyzed. RESULTS: Treatment with laver extract resulted in a significant decrease in lipid accumulation in 3T3-L1 adipocytes, which showed correlation with a reduction in expression of adipogenic proteins. Treatment with laver extract also resulted in a decrease in the viability of preadipocytes and an increase in the apoptosis of mature adipocytes. Treatment with laver extract led to exacerbated depletion of cellular glutathione and abolished the transient increase in GSH/GSSG ratio during adipogenesis in 3T3-L1 adipocytes. CONCLUSION: Results of our study demonstrated that treatment with the laver extract caused inhibition of adipogenesis, a decrease in proliferation of preadipocytes, and an increase in the apoptosis of mature adipocytes. It appears that these effects were caused by increasing oxidative stress, as demonstrated by the depletion and oxidation of the cellular glutathione pool in the extract-treated adipocytes. Our results suggest that a prooxidant role of laver extract is associated with its antiadipogenic and proapoptotic effects.

• The Journal of Advanced Prosthodontics
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• v.7 no.1
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• pp.21-26
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• 2015

PURPOSE. To evaluate the cytotoxicity of temporary luting cements on bovine dental pulp-derived cells (bDPCs). MATERIALS AND METHODS. Four different temporary cements were tested: Rely X Temp E (3M ESPE), Ultratemp (Ultradent), GC Fuji Temp (GC), and Rely X Temp NE (3M ESPE). The materials were prepared as discs and incubated in Dulbecco's modified eagle's culture medium (DMEM) for 72 hours according to ISO 10993-5. A real-time cell analyzer was used to determine cell vitality. After seeding $200{\mu}L$ of the cell suspensions into the wells of a 96-well plate, the bDPCs were cured with bioactive components released by the test materials and observed every 15 minutes for 98 hours. One-way ANOVA and Tukey-Kramer tests were used to analyze the results of the proliferation experiments. RESULTS. All tested temporary cements showed significant decreases in the bDPCs index. Rely X Temp E, GC Fuji Temp, and Rely X Temp NE were severely toxic at both time points (24 and 72 hours) (P<.001). When the cells were exposed to media by Ultratemp, the cell viability was similar to that of the control at 24 hours (P>.05); however, the cell viability was significantly reduced at 72 hours (P<.001). Light and scanning electron microscopy examination confirmed these results. CONCLUSION. The cytotoxic effects of temporary cements on pulpal tissue should be evaluated when choosing cement for luting provisional restorations.

• Korean Journal of Plant Tissue Culture
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• v.21 no.2
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• pp.117-121
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• 1994

The optimal level of growth regulator for callus initiation stem explants was BAP 0.1mg/L combined with 2,4-D 1.0 mg/L in Murashige and Skoog (MS) medium supplemented with 30g/L sucrose and 10g/L agar, and that for cell growth was BAP 0.1+2,4-D 0.5 mg/L in MS liquid medium. The regeneration frequency of P. oleracea cells was significantly increased by subjecting the cells to dessication for 1and 2 h up to 83%, respectively, as compared with untreated control showing 61%. Cell viability and survival rate was inhibited by pretreatment of 0.6% NaCl for 2 days, while regeneration ability was not affected by the treatment. Pretreatment of 100g/L sucrose for 2 days markedly stimulated the regeneration of cells up to 81%. These results suggest that in addition to physiological changes, water stress resulted from dessication and high concentration of sucrose and NaCl is closely related to the regeneration of P. oleracea cultured cells.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.12
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• pp.4937-4944
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• 2015

MicroRNAs (miRNAs) are emerging as critical regulators in carcinogenesis and tumor progression. Recently, miR-99a has been reported as a tumor suppressor gene in various human cancers, but its functions in the context of anaplastic thyroid cancer (ATC) remain unknown. In this study, we reported that miR-99a was commonly downregulated in ATC tissue specimens and cell lines with important functional consequences. Overexpression of miR-99a not only dramatically reduced ATC cell viability by inducing cell apoptosis and accumulation of cells at G1 phase, but also inhibited tumorigenicity in vivo. We then screened and identified a novel miR-99a target, mammalian target of rapamycin (mTOR), and it was further confirmed by luciferase assay. Up-regulation of miR-99a would markedly reduce the expression of mTOR and its downstream phosphorylated proteins (p-4E-BP1 and p-S6K1). Similar to restoring miR-99a expression, mTOR down-regulation suppressed cell viability and increased cell apoptosis, whereas restoration of mTOR expression significantly reversed the miR-99a antitumor activity and the inhibition of mTOR/p-4E-BP1/p-S6K1 signal pathway profile. In clinical specimens and cell lines, mTOR was commonly overexpressed and its protein levels were statistically inversely correlated with miR-99a expression. Taken together, our results demonstrated for the first time that miR-99a functions as a tumor suppressor and plays an important role in inhibiting the tumorigenesis through targeting the mTOR/p-4E-BP1/p-S6K1 pathway in ATC cells. Given these, miR-99a may serve as a novel prognostic/diagnostic and therapeutic target for treating ATC.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.5
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• pp.555-566
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• 2018

Human umbilical cord blood mesenchymal stem cells (hUCB-MSCs) are used in tissue repair and regeneration; however, the mechanisms involved are not well understood. We investigated the hair growth-promoting effects of hUCB-MSCs treatment to determine whether hUCB-MSCs enhance the promotion of hair growth. Furthermore, we attempted to identify the factors responsible for hair growth. The effects of hUCB-MSCs on hair growth were investigated in vivo, and hUCB-MSCs advanced anagen onset and hair follicle neogeneration. We found that hUCB-MSCs co-culture increased the viability and up-regulated hair induction-related proteins of human dermal papilla cells (hDPCs) in vitro. A growth factor antibody array revealed that secretory factors from hUCB-MSCs are related to hair growth. Insulin-like growth factor binding protein-1 (IGFBP-1) and vascular endothelial growth factor (VEGF) were increased in co-culture medium. Finally, we found that IGFBP-1, through the co-localization of an IGF-1 and IGFBP-1, had positive effects on cell viability; VEGF secretion; expression of alkaline phosphatase (ALP), CD133, and ${\beta}-catenin$; and formation of hDPCs 3D spheroids. Taken together, these data suggest that hUCB-MSCs promote hair growth via a paracrine mechanism.

• Proceedings of the Materials Research Society of Korea Conference
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• 2012.05a
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• pp.55.2-55.2
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• 2012

Intensive theoretical and experimental studies have been carried out at Korean Institute of Science and Technology (KIST) on controlling the bio absorbing rate of the Mg alloys with high mechanical strength through tailoring of electrochemical potential. Key technology for retarding the corrosion of the Mg alloys is to equalize the corrosion potentials of the constituent phases in the alloys, which prevented the formation of Galvanic circuit between the constituent phases resulting in remarkable reduction of corrosion rate. By thermodynamic consideration, the possible phases of a given alloy system were identified and their work functions, which are related to their corrosion potentials, were calculated by the first principle calculation. The designed alloys, of which the constituent phases have similar work function, were fabricated by clean melting and extrusion system. The newly developed Mg alloys named as KISTUI-MG showed much lower corrosion rate as well as higher strength than previously developed Mg alloys. Biocompatibility and feasibility of the Mg alloys as orthopedic implant materials were evaluated by in vitro cell viability test, in vitro degradation test of mechanical strength during bio-corrosion, in vivo implantation and continuous observation of the implant during in vivo absorbing procedures. Moreover, the cells attached on the Mg alloys was observed using cryo-FIB (focused ion beam) system without the distortion of cell morphology and its organ through the removal of drying steps essential for the preparation of normal SEM/TEM samples. Our Mg alloys showed excellent biocompatibility satisfying the regulations required for biomedical application without evident hydrogen evolution when it implanted into the muscle, inter spine disk, as well as condyle bone of rat and well contact interface with bone tissue when it was implanted into rat condyle.

• Clinical and Experimental Reproductive Medicine
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• v.27 no.2
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• pp.145-149
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• 2000

Objective: The present study was conducted to evaluate the viability of germ cells from the adult and fetal ovarian tissues after vitrification followed by xenografting. Method: The human adult ovarian tissues were obtained from 33 years old patient, and the fetal ovarian tissues were obtained from 22 weeks and 25 weeks in gestation. Ovarian tissues were cryopreserved by vitrification with 5.5 M ethylene glycol (EG 5.5) and 1.0 M sucrose as cryoprotectants. Adult and fetal ovarian tissues were pre-equilibrated with EG 5.5 at room temperature for 10 and 5 minutes, respectively and plunged into liquid nitrogen immediately. Frozen-thawed tissues were xenografted into NOD-SCID mice to evaluate the viability and capacity for further growth of the primordial follicles. Grafts were recovered from the recipients 4 weeks after transplantation and histological analysis was accomplished. Result and Conclusion: Grafts recovered 4 weeks after transplantation contained less number of oocytes and primordial follicles compared to that of the fresh tissues. Survived follicles were mainly primordial and intermediary with larger diameter and more granulosa cells. It is confirmed that 1) the ovarian tissues were healthy and the germ cells were survived after vitrification, and 2) the survived fetal primordial follicles after vitrification resumed the growth in the xenografts.