Khang, Gilson;Rhee, John M.;Shin, Philkyung;Kim, In Young;Lee, Bong;Lee, Sang Jin;Lee, Young Moo;Lee, Hai Bang;Lee, Ilwoo
Macromolecular Research
/
v.10
no.3
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pp.158-167
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2002
In order to endow with new bioactive functionality from small intestine submucosa (SIS) powder as natural source to poly (L-lactide) (PLA) and poly (lactide-co-glycolide) (PLGA) synthetic biodegradable polymer, porous SIS/PLA and SIS/PLGA as natural/synthetic composite scaffolds were prepared by means of the solvent casting/salt leaching methods for the possibility of the application of tissue engineered bone and cartilage. A uniform distribution of good interconnected pores from the surface to core region was observed the pore size of 40~500 ${\mu}{\textrm}{m}$ independent with SIS amount using the solvent casting/salt leaching method. Porosities, specific pore areas as well as pore size distribution also were almost same. After the fabrication of SIS/PLA hybrid scaffolds, the wetting properties was greatly enhanced resulting in more uniform cell seeding and distribution. Five groups as PGA non-woven mesh without glutaraldehyde (GA) treatment, PLA scaffold without or with GA treatment, and SIS/PLA (Code No.3 ; 1 : 12 of salt content, (0.4 : 1 of SIS content, and 144 ${\mu}{\textrm}{m}$ of median pore size) without or with GA treatment were implanted into the back of nude mouse to observe the effect of SIS on the induction of cells proliferation by hematoxylin and eosin, and von Kossa staining for 8 weeks. It was observed that the effect of SIS/PLA scaffolds with GA treatment on bone induction are stronger than PLA scaffolds, that is to say, in the order of PLA/SIS scaffolds with GA treatment > PLA/SIS scaffolds without GA treatment > PGA nonwoven > PLA scaffolds only with GA treatment = PLA scaffolds only without GA treatment for the osteoinduction activity. The possible explanations are (1) many kinds of secreted, circulating, and extracellular matrix-bound growth factors from SIS to significantly affect critical processes of tissue development and differentiation, (2) the exposure of SIS to GA resulted in significantly calcification, and (3) peri-implant fibrosis due to covalent bonding between collagen molecule by crosslinking reaction. In conclusion, it seems that SIS plays an important role for bone induction in SIS/PLA scaffolds for the application of tissue engineering area.
Transient neonatal diabetes mellitus (TNDM) has been associated with paternal uniparental isodisomy of chromosome 6, paternally inherited duplication of 6q24, or a methylation defect at a CpG island of the ZAC or HYMAI gene. We experienced a case of TNDM in which the patient presented with hyperglycemia, macroglossia, and intrauterine growth retardation, caused by a paternally derived HYMAI. An 18-day-old female infant was admitted to the hospital because of macroglossia and recurrent hyperglycemia. In addition to the macroglossia, she also presented with large fontanelles, micrognathia, and prominent eyes. Serum glucose levels were 200-00 mg/dL and they improved spontaneously 2 days after admission. To identify the presence of a maternal methylated allele, bisulfite-treated genomic DNA from peripheral blood was prepared and digested with BssHII after polymerase chain reaction (PCR) amplification with methylation-specific HYMAI primers. PCR and restriction fragment length polymorphism analysis showed that the patient had only the paternal origin of the HYMA1 gene. TNDM is associated with a methylation defect in chromosome 6, suggesting that an imprinted gene on chromosome 6 is responsible for this phenotype.
Salmonella infections cause the disease in pigs but also some zoonotic Salmonella serotypes can be transmitted to human through swine products, resulting in food poisoning. The objective of this study was to investigate the bacteriological prevalence and detection of invA gene using Salmonella specific polymerase chain reaction (PCR), the epidemiological characteristics related to Salmonella strains cultured from pig samples in Gangwon areas using serotyping, random amplified polymorphic DNA (RAPD) and pulsed field gel electrophoresis (PFGE) methods. During the period of November 2001 through April 2002, 1,174 ileocecal lymph node were collected from the slaughtered pigs raised in 38 farms located in Gangwon province. The samples were submerged in boiling water and macerated in saline and lymph node homogenates were inoculated into Tetrathionate broth with iodine (TTB, Difco, 0.5% iodine was added) for enrichment growth. Then additional tests were performed using several mediums, and suspects were identified by API 20E kit (BioMerieux) and PCR. Of total 1,174 samples from 38 farms, 44 (3.7%) were isolated as Salmonella spp from 13 farms (34.2%). Of 44 isolates, 31 were in Yangyang region, followed by 9 in Goseong, 2 in both Gangneung and Sokcho. However, there was no difference in regional isolation frequency. All isolates have a 521bp amplified product in Salmonella specific PCR with primer invA which encodes in proteins for invasion of epithelial cells. Of 44 recovered serotypes, 23 (52.3%) were S Eingedi, 10 (22.7%) S Schwarzengrund, 9 (20.5%) S Typhimurium, and 2 (4.5%) S Mbandaka. In RAPD analysis, there appeared to be unique bands distinguishing each serotype, although similarities exist between the different serotypes. Four serotypes of 44 Salmonella isolates appeared to fall into 14 different RAPD types. In PFGE analysis, 9 S Typhimurium were tested with XbaI enzyme and SpeI enzyme. The combination of results obtained with two enzymes subdivided the 9 S Typhimurium into 4 PFGE types.
Cho, Sun Ah;Song, Jeong Eun;Kim, Kyoung Hee;Ko, Hyun Ah;Lee, Dongwon;Kwon, Soon Yong;Chung, Jin Wha;Khang, Gilson
Polymer(Korea)
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v.37
no.5
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pp.632-637
/
2013
It has been widely accepted that costal cartilage cells (CCs) have more excellent initial proliferation capacity than articular cartilage cells as well as the easiness for isolation and collection. This study demonstrated that CCs might be one of the substitutes for articular cartilage cells by tissue engineered cartilage. Poly(lactic-co-glycolic acid) (PLGA) has been extensively tested and used as scaffold material but it was limited by the low attachment of cells and the induction of inflammatory cells. Base on previous our studies, we confirmed demineralized bone particle (DBP) had the power of the reduction of inflammatory reaction and the stimulation proliferation of cells. We fabricated PLGA scaffold loaded with 10, 20, 40 and 80 wt% DBP and then tested the possibility of the regeneration of cartilage using CCs. Assays of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and scanning electron microscope (SEM) carried out to evaluate the attachment and proliferation of CCs in DBP/PLGA scaffolds. Glycosaminoglycan (sGAG) and collagen contents assay were conducted to confirm the effects of DBP on formation of extracellular matrix. This study demonstrated that DBP/PLGA scaffolds showed significant positive effects on cell growth and proliferation due to the vitality of DBP as well as the possibility of the application of CCs for tissue engineered cartilage.
Kim, Hyun-Soo;Zheng, Mingzhen;Kim, Do-Kyung;Lee, Won-Pyo;Yu, Sang-Joun;Kim, Byung-Ock
Journal of Periodontal and Implant Science
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v.48
no.1
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pp.34-46
/
2018
Purpose: The purpose of this study was to evaluate the effects of 1,25-dihydroxyvitamin $D_3$ on the proliferation, differentiation, and matrix mineralization of MC3T3-E1 osteoblast-like cells in vitro. Methods: MC3T3-E1 osteoblastic cells and 1,25-dihydroxyvitamin $D_3$ were prepared. Cytotoxic effects and osteogenic differentiation were evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, alkaline phosphatase (ALP) activity assay, ALP staining, alizarin red S staining, and reverse transcription-polymerase chain reaction (RT-PCR) for osteogenic differentiation markers such as ALP, collagen type I (Col-I), osteocalcin (OCN), vitamin D receptor (VDR), and glyceraldehyde 3-phosphate dehydrogenase. Results: The MTT assay showed that 1,25-dihydroxyvitamin $D_3$ did not inhibit cell growth and that the rate of cell proliferation was higher than in the positive control group at all concentrations. ALP activity was also higher than in the positive control group at low concentrations of 1,25-dihydroxyvitamin $D_3$ ($10^{-10}$, $10^{-12}$, and $10^{-14}M$). RT-PCR showed that the gene expression levels of ALP, Col-I, OCN, and vitamin D receptor (VDR) were higher at a low concentration of 1,25-dihydroxyvitamin $D_3$ ($10^{-12}M$). Alizarin red S staining after treatment with 1,25-dihydroxyvitamin $D_3$ ($10^{-12}M$) showed no significant differences in the overall degree of calcification. In contrast to the positive control group, formation of bone nodules was induced in the early stages of cell differentiation. Conclusions: We suggest that 1,25-dihydroxyvitamin $D_3$ positively affects cell differentiation and matrix mineralization. Therefore, it may function as a stimulating factor in osteoblastic bone formation and can be used as an additive in bone regeneration treatment.
Structural and thermo-analytical studies were carried out to understand the phase formation kinetics of the single phase $Bi_5Ti_3FeO_{15}$ (BTFO) nanocrystals in $Bi_2O_3-Fe_2O_3-TiO_2$, during the polymerized complex (PC) synthesis method. The crystallization of Aurivillius phase $Bi_5Ti_3FeO_{15}$ layered perovskite was found to be initiated and achieved under the temperature conditions in the range of ${\sim}$800 to 1050$^{\circ}C$. The activation energy for grain growth of $Bi_5Ti_3FeO_{15}$ nanocrystals (NCs) was very low in case of NCs formed by PC (2.61 kJ/mol) than that formed by the solid state reaction (SSR) method (10.9 kJ/mol). The energy involved in the phase transformation of Aurivillius phase $Bi_5Ti_3FeO_{15}$ from $Bi_2O_3-Fe_2O_3-TiO_2$ system was ${\sim}$ 69.8 kJ/mol. The formation kinetics study of $Bi_5Ti_3FeO_{15}$ synthesized by SSR and PC methods would not only render a large impact in the nanocrystalline material development but also in achieving highly efficient visible photocatalysts.
Highly Activated Calcium(below HAC) is the oxidized calcium made by dissolving shell materials with high voltage about 15,000V and high temperature ($1,500{\sim}5,000^{\circ}C$). This HAC is a material with a very high degree of purity without toxicant. This HAC decreases chemical reaction so the degree of being active and dissolving living material is outstanding. The effects of HAC on the propagation of mushrooms are following. In the case of the Pleurotus ostreatus, when controlling media moisture by mixing with the HAC, mycelium cultivating days were shortened by 2days. The day required for primordial formation after inoculation(DPI) were one day faster. The number of stem was 15 and individual weight was 248g/850cc, a 6.5% increase. In the case of Pleurotus eryngii, when controlling media moisture by mixing with the highly activated calcium, mycelium cultivating days were shortened by 3days. DPI were l day faster. The day required for colonization after inoculation was shortened by 6days and individual weight was 108.8g/850cc, a 9.7% increase. In the case of Flammulina velutipes, the highly activated calcium was the best for scraping up mycelium. Mycelium incubating days were shortened by 2days. DPI were shortened by 3days. The day required for colonization after inoculation was 1day faster and the period of cultivation was shortened by 3days. Individual weight was 165g/850cc, a 6.7% increase. In the case of Lentinula edodes, when mixing media with the highly cultivated calcium, cultivating days were shortened by 3 days. The days for becoming brown in color were 2 days faster and the days of the first harvest were shortened by 4 days. The weight of mushrooms was 169g/2kg, a 9.7% increase.
Jeon, Mi-Ae;Kwon, Hyun-Jung;Kim, Yong-Hyun;Han, Kook-Il;Chung, Ha-Na;Chung, Sung-Kyun;Bang, In Seok;Han, Man-Deuk
Journal of dental hygiene science
/
v.10
no.5
/
pp.365-372
/
2010
Caesalpinia sappan L. has long been commonly used in oriental folk medicines and as dyes materials. To investigate the antioxidative activities and antiproliferation effects of brazilin from C. sappan heart wood, the MeOH soluble extract was successively fractionated by using hexane, $CHCl_{3}$, EtOAc, BuOH, MeOH, and $H_{2}O$. In these fractions, we were purified brazilin from EtOAc fraction which partitioned to 3.94% of the highest yields. The effects of brazilin and the extracts on human oral carcinoma cells (KB) by MTT assay and their antioxidant activities by DPPH, TCA assay and Fenton reaction were tested. The results showed that the brazilin could inhibits the proliferation of KB cells and obviously decreased the production of nitric oxide of the cells. When the concentration of the brazilin reached to $100\;{\mu}g/ml$, the inhibition percentage of the cell growth was about 60%. In assay on antioxidant activities, The results showed that brazilin exhibit the highest capacity of DPPH free radical scavenging effects among tested extracts. When the concentration of brazilin reached to 1 mg/ml, the lipid peroxide inhibition and radical inhibition activities were determined to be 65.0% and 85.8%, respectively. These results are suggest that brazilin have stronger antiproliferation effect on KB cell and antioxidant properties.
To investigate the effects of storage and pasteurization temperature on the quality of kiwi juice $(13.5^{\circ}Brix)$, the Kiwi juice was pasteurized at 65, 75 and $85^{\circ}C$ for 15 sec. The microbial, physicochemical measurements and sensory evaluations were conducted at the same condition during storage at 4 and $25^{\circ}C$ for 30 days. Most of the vegetative bacteria cells in kiwi juice were destroyed by heat treatment over $65^{\circ}C$, and they did not actively grow in kiwi juice after pasteurization. The D values of bacteria in kiwi juice by tubular type of heating exchange were 4.17, 1.47 and 0.81 sec at 65, 75 and $85^{\circ}C$, respectively. The growth of microorganisms during storage were not detected in the most samples. The amounts of vitamin C decreased as the pasteurization-storage-temperature and storage time increased. While reducing sugar increased as the pasteurization-storage temperature-storage time increased, it decreased rapidly after 20 days of storage. Hunter's color values L, a and b of stored kiwi juice were decreased at all storage conditions, browning reaction rate increased as the pasteurization-storage-temperature was decreased.
Sasa quelpaertensis Nakai (Korean name, Jeju-Joritdae) is one of the most abundant plants on Mt. Halla, Jeju Island, and it has long been used in traditional medicines. Recent studies have reported it as possessing various beneficial functions, including anti-inflammatory, anti-diabetic, anti-hypertension, anti-gastritis, anti-oxidant, and anti-cancer effects. However, the molecular mechanisms of its anti-cancer activity have not been clearly elucidated. In this study, we investigated the anti-cancer effects and mechanism of S. quelpaertensis on human colon cancer HT-29 cells. Cell growth inhibition by S. quelpaertensis was determined by MTT assay. Apoptosis was performed by DNA fragmentation, flow cytometry with propidium iodide staining (PI), and reverse transcription-polymerase chain reaction (RT-PCR) to confirm the anti-apoptotic factors, such as inhibitor of apoptosis (IAP) family members. $NO^{\bullet}$ production was determined by Griess assay. S. quelpaertensis treatment resulted in the time- and dose-dependent inhibition of the cell viability of HT-29 cells by inducing apoptosis, as evidenced by the accumulation of the sub-G1 cell population stained by PI, as well as the ladder-like DNA fragmentation in a dose-dependent manner. S. quelpaertensis-inducing apoptosis was accompanied by the induction of S cell cycle arrests, increasing $NO^{\bullet}$ concentrations, and the down-regulation of IAPs, including X-chromosome-linked IAP (XIAP), cellular IAP-1 (cIAP-1), cIAP-2, and survivin. Taken together, these findings have important implications for future clinical developments of S. quelpaertensis in colon cancer treatment.
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