• Korean Journal of Materials Research
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• v.24 no.12
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• pp.671-676
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• 2014

It is known that bones get damaged by accidents and aging. Since the discovery of Bioglass, various kinds of ceramics have been also found to bond to living bone; some of these ceramics are already being clinically used as bone-repairing materials. In the present study, antibacterial calcium silicate gel ($Ag-30CaO{\cdot}70SiO_2$ gel) was prepared by sol-gel method in order to control the microstructure, which is related to the dissolution rate and induction period of apatite formation in body environment. In addition, biological $Ag-30CaO{\cdot}70SiO_2$ is tested. This was done to impart antimicrobial activity to the $30CaO{\cdot}70SiO_2$. Ag ion was added during sol-gel synthesis to replace the $H_2O$ added during the making of the $30CaO{\cdot}70SiO_2$ gel, which has silver solutions of various concentration. After the sol-gel process, 1N-$HNO_3$ solution was used to wash the gel when synthesizing the gel, in order to maintain the porous structure and remove PEG, water soluble polymers. Then, the apatite forming ability of the sol-gel derived CaO-$SiO_2$ gels was investigated using simulated body fluid (SBF), which had almost the same ion concentration as that of human blood plasma. The gels were analyzed by FT-IR spectroscopy, SEM observation, XRD, and fluorescent microscopy. The apatite was successfully created even after washing the gel; apatite is present in an amorphous state, and was found to affect the concentration of the Ag ion in cells in MC3T3 live & dead assay results. From these results, it is suggested that a good material that can be used to repair defects of nature bone is $Ag-30CaO{\cdot}70SiO_2$ gel.

• Korean Journal of Pharmacognosy
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• v.38 no.2 s.149
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• pp.101-107
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• 2007

This study was carried out to examine the in vitro effects of alginate (LVA) which is low viscosity alginic acid, on collagen type II synthesis of chondrocytes and the in vivo effect, orally administered, on cartilage degradation. Rabbit articular chondrocytes were cultured in 35 mm dishes and then LVA was treated. The effects of LVA of various viscosity (86.5 cP(LVA1),45.4 cP(LVA2), 21.2 cP(LVA3) and 9.6 cP(LVA4)) and various concentration (50, 100, 200 ${\mu}$g/ml of LVA4) on chondrocytes were determined by western blotting assay for the detection of collagen type II production. In western blotting assay, collagen type II production in chondrocytes were 1.00 in control,0.95 in LVA1, 1.41 in LVA2, 1.57 in LVA3 and 1.58 in LVA4. Collagen type II production of various concentration of LVA4 were 1.00 in control, 1.24 in 50 ${\mu}$g/ml of LVA4, 1.52 in 100 ${\mu}$g/ml of LVA4 and 1.86 in 200 ${\mu}$g/ml of LVA4. Osteoarthritis (OA) was induced in 24 rabbits by unilateral anterior cruciate ligament transection (ACLT) and randomly divided into 6 groups. The experimental group was given oral administration of 0.5 ml/kg of saline(control), 12.5 mg/kg of LVA (A12.5), 25 mg/kg of LVA (A25), 50 mg/kg of LVA (A5O), 75 mg/kg of LVA (A75) and 20 mg/kg of aceclofenac (AC) for 6 weeks after ACLT. All knees were harvested at 6 weeks after surgery and cartilage degradation was evaluated. Cartilage degradation in the control group was significantly more severe than that in the A25, A5O and A75 groups but AC group had no significant changes on the macroscopic grading scale.

• Journal of Plant Biotechnology
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• v.32 no.4
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• pp.293-300
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• 2005

The possible role of nitric oxide (NO)-induced cell division was investigated to explain the physiologycal effects of a NO donor, sodium nitroprusside (SNP) on the growth of primary leaves in chinese cabbage seedling plants. Exogenous treatment of SNP to chinese cabbage plants for 8 days at different concentrations (0, 200, 500 and 1000 ${\mu}M$) affected the leaf growth in a concentration-dependent manner, showing a maximum growth at $200\;{\mu}M$. In accordance with leaf growth responses, the chlorophyll and soluble protein contents increased strongly to 142% and 134% of control at $200\;{\mu}M$ SNP, respectively. However, a very little decrease in chlorophyll and a 13%> decrease in protein were observed at $1000\;{\mu}M$ SNP. In addition, the content of DNA and RNA also increased maximumly to 142% and 139% of the control at $200\;{\mu}M$ SNP, respectively, whereas they decreased to 80% and 84% of the control at $1000\;{\mu}M$ SNP. With respect to the development of enzymes related to cell wall synthesis, $200\;{\mu}M$ SNP led to the maximum activities in both phenylalanine ammonia-lyase (212% of the control) and guaiacol peroxidase (134% of the control). However, the activities of both enzymes were not modified significantly at $1000\;{\mu}M$ SNP. In conclusion, these results suggest that the enhancement of leaf growth in chinese cabbage plants by SNP at the effective concentration was probably due to the NO ability in the induction of cell division.

• Microbiology and Biotechnology Letters
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• v.40 no.2
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• pp.92-97
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• 2012

Antimicrobial peptides (AMPs) are important components of living organisms acting against Gram-negative and Gram-positive bacterial and fungal pathogens. Cathelicidin human peptides have a variety of biological activities that can be used in clinical applications. AMPs are not produced naturally in large quantities, and chemical synthesis is also economically impractical, especially for long peptides. Therefore, as an alternative, heterologous expression of AMPs by recombinant techniques has been studied as a means to reduce production costs. E. coli is an excellent host for the expression of AMPs, as well as other recombinant proteins, because of the low cost involved and its easy manipulation. However, overexpression of AMPs in E. coli has been shown to cause difficulties resulting from the toxicity of the subsequently produced AMPs. Therefore, fusion expression was theorized to be a solution to this problem. In this study, AMPs were expressed as fused proteins with the glutathione S-transferase (GST) binding protein to protect against the toxicity of AMPs when expressed in E. coli. The LL37, and hybrid gaegurin and LL37 (GGN4(1-16)-LL37(17-32), which we designated as GL32, peptides were expressed as GST-fusion proteins in E. coli and the fusion proteins were then purified by affinity columns. The purified peptides were obtained by removal of GST and were confirmed by western blot analysis. The purified antimicrobial peptides then demonstrated antimicrobial activities against Gram-negative and Gram-positive bacterial strains.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.1
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• pp.49-54
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• 2014

Background: Hydrogels are a class of polymers that can absorb water or biological fluids and swell to several times their dry volume, dependent on changes in the external environment. In recent years, hydrogels and hydrogel nanocomposites have found a variety of biomedical applications, including drug delivery and cancer treatment. The incorporation of nanoparticulates into a hydrogel matrix can result in unique material characteristics such as enhanced mechanical properties, swelling response, and capability of remote controlled actuation. Materials and Methods: In this work, synthesis of hydrogel nanocomposites containing magnetic nanoparticles are studied. At first, magnetic nanoparticles ($Fe_3O_4$) with an average size 10 nm were prepared. At second approach, thermo and pH-sensitive poly (N-isopropylacrylamide -co-methacrylic acid-co-vinyl pyrrolidone) (NIPAAm-MAA-VP) were prepared. Swelling behavior of co-polymer was studied in buffer solutions with different pH values (pH=5.8, pH=7.4) at $37^{\circ}C$. Magnetic iron oxide nanoparticles ($Fe_3O_4$) and doxorubicin were incorporated into copolymer and drug loading was studied. The release of drug, carried out at different pH and temperatures. Finally, chemical composition, magnetic properties and morphology of doxorubicin-loaded magnetic hydrogel nanocomposites were analyzed by FT- IR, vibrating sample magnetometry (VSM), scanning electron microscopy (SEM). Results: The results indicated that drug loading efficiency was increased by increasing the drug ratio to polymer. Doxorubicin was released more at $40^{\circ}C$ and in acidic pH compared to that $37^{\circ}C$ and basic pH. Conclusions: This study suggested that the poly (NIPAAm-MAA-VP) magnetic hydrogel nanocomposite could be an effective carrier for targeting drug delivery systems of anti-cancer drugs due to its temperature sensitive properties.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.8
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• pp.4086-4092
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• 2013

Mycosporine-like amino acids (MAAs) are UV-absorbing substances, and diverse marine organisms have the evolved the capacity to diminished the direct and indirect damaging effects of environmental ultraviolet radiation by synthesis and accumulation of MAAs. In this study, we manufactured a radiofrequency (RF) generation device and applied to microalgal culture. $0.35{\pm}0.05$ mHz of RF was supplied to culture vessel for Chlamydomonas sp. and samples were harvested at the designated time intervals (1, 0.5, 1 and 2 hr). MAAs biosynthetic genes, dehydroquinate synthase homolog (DHQS-like) and nonribosomal peptide synthetase homolog (NRPS-like), were cloned from Chlamydomonas sp. and their gene expressions under the RF exposure were analyzed using qRT-PCR. DHQS-like and NRPS-like gene expressions of Chlamydomonas sp. exposed to RF were increased 1.46 and 1.19 fold at 1 hr, respectively. These results means that DHQS-like and NRPS-like genes can be good biomarker candidates for diagnosis of MAAs biosynthesis in the Chlamydomonas sp.

• Journal of the Korean Applied Science and Technology
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• v.37 no.2
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• pp.241-249
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• 2020

This study investigated the whitening activity using seomaeyakssuk (Artemisia argyi H.) extract. Seomaeyakssuk was extracted from hot DW (AAD) and 70% ethanol (AAE). And confirmed safety through assessment of cytotoxicity. Also, whitening activities were measured through changes in the levels of extracellular melanin, melanin synthesis, cellular tyrosinase activity and transcription factor. The results confirmed that significant cytotoxicity does not appear in the concentration range of 50, 100, and 200 ㎍/㎖ of both extracts of this study. The production of extracellular melanin was slowed by AAD 45.0% and AAE 1.3% at 200 ㎍/㎖ concentration. Also, production of intracellular melanin was decreased AAD 37.2% and AAE 24.6%. In the case of intra cellular tyrosinase activity was reduced to AAD 49.2% and AAE 35.6% at 200 ㎍/㎖ concentration. The mRNA expression of tyrosinase, TRP-1 and TRP-2 significantly decreased by AAD 63.0%/AAE 58.0%, AAD 60.0%/AAE 56.0% and AAD 59.0%/AAE 53.0%, respectively, following the 200 ㎍/㎖ sample treatment when compared to the control. Both extracts showed efficient changes of production of whitening-related factor and transcription factor. But AAD was found to have a higher inhibitory effect than AAE. In other words, seomaeyakssuk was showed significant biological activities showing whitening without cytotoxicity. These results will be provided as fundamental data for further development of the new material of functional cosmetics to the results above.

• YAKHAK HOEJI
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• v.53 no.5
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• pp.293-297
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• 2009

The abuse of methamphetamine (MA) is one of the most serious drug abuses in Asia. And, the prevention of precursor production for abuse drug is one of the most effective drug control system. Isotope ratio analysis at natural abundance levels have been used to establish the environmental source or the geographic origin of various biological and nonbiological materials. Ephedrine, the precursor of MA, is produced by one of three methods; extraction from Ephedra plants, full chemical synthesis or via a semi-synthetic process involving the fermentation of sugar, followed by amination. We investigated the origin of ephedrine and pseudoephedrine based on the carbon and nitrogen values for nineteen pharmaceutical powder materials (PPMs) obtained from pharmaceutical company in Korea by stable isotope ratio mass spectrometry coupled to an elemental analyser (EA-IRMS). The carbon delta values for the ephedrine and pseudoephedrine were -24.21~-22.72 (mean=-23.72) $^{\cir}/_{\circ\circ}$ and -23.79~-22.71 (mean=-23.48) $^{\cir}/_{\circ\circ}$. The nitrogen delta values were 3.51~5.55 (4.43) $^{\cir}/_{\circ\circ}$ and 2.24~8.22 (5.42) $^{\cir}/_{\circ\circ}$. These results indicate that PPMs are semi-synthetic products. Therefore the origins of ephedrine(natural, semi-synthetic or synthetic) could be discriminated by using carbon and nitrogen stable isotope ratios. we are sure tat this stable isotope ratio analysis can discriminate the origins of precursors of methamphetamine.

• Journal of Sericultural and Entomological Science
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• v.51 no.2
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• pp.191-196
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• 2013

This study was aimed for development of a useful genes that has a transcript expressional specificity in the early embryonic stage of the silkworm, Bombyx mori. We constructed and analyzed a full-length cDNA library from silkworm's eggs which after a lapse of 2 ~ 6 hours post oviposit. A total 960 clones were randomly selected, and the 5' ends of the inserts were sequenced to generate 652 expressed sequence tags(EST). 334 unique ESTs were generated after the assembly of 652 ESTs. The annotation of 334 unique ESTs by BLAST search revealed that 156(47%) of the sequences represented known genes, whereas 178(53%) of the sequences has no matches in the database. Of the 156 known genes, the most abundant genes were heat shock protein hsp20.8 gene(12 times) and ubiqutin-like protein gene(11 times). The functional groups of these ESTs with matches in the database were constructed according to their putative molecular functions. Among thirteen functional categories, the largest groups were protein synthesis(9.6%) and cellular organization( 8.1%). Further defined studies on molecular functions and biological roles of their promoters will give us wellfined information and its application.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.18
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• pp.8553-8557
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• 2016

Background: Accurate dose assessment and correct identification of irradiated from non-irradiated people are goals of biological dosimetry in radiation accidents. Objectives: Changes in the FDXR and the RAD51 gene expression (GE) levels were here analyzed in response to total body exposure (TBE) to a 6 MV x-ray beam in rats. We determined the accuracy for absolute quantification of GE to predict the dose at 24 hours. Materials and Methods: For this in vivo experimental study, using simple randomized sampling, peripheral blood samples were collected from a total of 20 Wistar rats at 24 hours following exposure of total body to 6 MV X-ray beam energy with doses (0.2, 0.5, 2 and 4 Gy) for TBE in Linac Varian 2100C/D (Varian, USA) in Golestan Hospital, in Ahvaz, Iran. Also, 9 rats was irradiated with a 6MV X-ray beam at doses of 1, 2, 3 Gy in 6MV energy as a validation group. A sham group was also included. After RNA extraction and DNA synthesis, GE changes were measured by the QRT-PCR technique and an absolute quantification strategy by taqman methodology in peripheral blood from rats. ROC analysis was used to distinguish irradiated from non-irradiated samples (qualitative dose assessment) at a dose of 2 Gy. Results: The best fits for mean of responses were polynomial equations with a R2 of 0.98 and 0.90 (for FDXR and RAD51 dose response curves, respectively). Dose response of the FDXR gene produced a better mean dose estimation of irradiated "validation" samples compared to the RAD51 gene at doses of 1, 2 and 3 Gy. FDXR gene expression separated the irradiated rats from controls with a sensitivity, specificity and accuracy of 87.5%, 83.5% and 81.3%, respectively, 24 hours after dose of 2 Gy. These values were significantly (p<0.05) higher than the 75%, 75% and 75%, respectively, obtained using gene expression of RAD51 analysis at a dose of 2 Gy. Conclusions: Collectively, these data suggest that absolute quantification by gel purified quantitative RT-PCR can be used to measure the mRNA copies for GE biodosimetry studies at comparable accuracy to similar methods. In the case of TBE with 6MV energy, FDXR gene expression analysis is more precise than that with RAD51 for quantitative and qualitative dose assessment.