• Journal of Microbiology and Biotechnology
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• v.24 no.4
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• pp.522-533
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• 2014

Bionanotechnology has revolutionized nanomaterial synthesis by providing a green synthetic platform using biological systems. Among such biological systems, microalgae have tremendous potential to take up metal ions and produce nanoparticles by a detoxification process. The present study explores the intracellular and extracellular biogenic syntheses of silver nanoparticles (SNPs) using the unicellular green microalga Scenedesmus sp. Biosynthesized SNPs were characterized by AAS, UV-Vis spectroscopy, TEM, XRD, FTIR, DLS, and TGA studies and finally checked for antibacterial activity. Intracellular nanoparticle biosynthesis was initiated by a high rate of $Ag^+$ ion accumulation in the microalgal biomass and subsequent formation of spherical crystalline SNPs (average size, 15-20 nm) due to the biochemical reduction of $Ag^+$ ions. The synthesized nanoparticles were intracellular, as confirmed by the UV-Vis spectra of the outside medium. Furthermore, extracellular synthesis using boiled extract showed the formation of well scattered, highly stable, spherical SNPs with an average size of 5-10 nm. The size and morphology of the nanoparticles were confirmed by TEM. The crystalline nature of the SNPs was evident from the diffraction peaks of XRD and bright circular ring pattern of SAED. FTIR and UV-Vis spectra showed that biomolecules, proteins and peptides, are mainly responsible for the formation and stabilization of SNPs. Furthermore, the synthesized nanoparticles exhibited high antimicrobial activity against pathogenic gram-negative and gram-positive bacteria. Use of such a microalgal system provides a simple, cost-effective alternative template for the biosynthesis of nanomaterials in a large-scale system that could be of great use in biomedical applications.

• Advances in Traditional Medicine
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• v.4 no.2
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• pp.112-119
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• 2004

Glutathione S-transferase polymorphisms (GST) were examined in 98 cases with cerebrovascular disease (CVD) to test the hypothesis that GST polymorphisms confer a risk to an individual to develop CVD. Tobacco smoke is a major cause of both cancer and vascular disease. We therefore were stratified the subjects with CVD for smoking status, and then examined whether polymorphisms in this detoxification enzyme gene, GST, influence risk of CVD. Neither GSTM1 nor GSTT1 genotypes in the CVD group was significantly different from the control group (n=230), even in smokers. We attempted the combined analyses for GSTM1 and GSTT1 genotypes in CVD for smoking status. No significant association observed between the combined genotypes and CVD. We also classified the subjects and control group into four types according to Sasang Constitutional Medicine, Korean Traditional Oriental Medicine, and investigated the association among GST genotypes, CVD, and Sasang constitutional classification. Our observations do not confirm the effect of the GSTM1 and GSTT1 genotypes as a risk factor for CVD, even in smokers. Furthermore, we first attempted to evaluate the efficacy of Sasang Constitutional Medicine, and to find an association with CVD.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.6
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• pp.640-645
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• 2004

An eight-week-old male ICR mouse, which was induced with acute alcohol and sub-acute alcohol poisoning condition, was administered with bohee tea(Camelia sinensis L) extract. Under the inducement of the sub-acute alcohol poisoning condition, no considerable differences could be found in the blood alcohol concentration of the positive control group and the bohee tea group(p<0.05). The GOT activity of the three groups: bohee tea, Drink, and Alcodex decreased than that of the normal control group(9.064±4.687 unit)(p<0.05). In addition, the blood GOT activity of the dark green tea group dropped by 81.44% compared with that of the positive control group. On the other hand, the blood GTP activity of the bohee tea group decreased by 5.2% as opposed to that of the positive control and the Drink that decreased by 7.5% as opposed to that of the positive control. The hepatic ADH activity of the bohee tea increased by 22.7%, as opposed to that of the positive control group. The Drink, however, had an increase rate of 33.6%. In the case of the hepatic ALDH activity of the liver, no significant differences were ever recorded among all groups, except for the positive control group. Due to an intake of bohee tea extract, the hepatic ALDH activity decreased by 77.27% which could not be seen in the positive control group. However, Drink and A1codex had a decrease could be seen(p<0.05).

• Journal of the East Asian Society of Dietary Life
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• v.14 no.6
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• pp.634-639
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• 2004

An eight-week-old male ICR mouse, which was induced with acute alcohol and sub-acute alcohol poisoning condition, was administered with bohee tea(Camelia sinensis L) extract. After oral administration of bohee tea and inducement of acute alcohol poisoning condition, the mouses blood alcohol concentration became as low as that of the normal control group. Its decrease rate was 87.26%, in comparison with that of the positive control group. Moreover, its blood GOT activity decreased with a rate of 93.1 % until it reached the normal level, as opposed to that of the positive control group. In addition, the GOT activity, despite rising after the alcohol intake, decreased(p<0.05) significantly after administration of each sample and reached the normal level. The bohee tea group experienced a significant decrease in the GOT activity, compared with the A1codex group and the Drink group. The GPT activity of the Alcodex group decreased by 11 % compared with that of the positive control group. The CTP activity of the bohee tea group decreased by 8.2%, while that of the Drink group decreased by 6.5%(P<0.05). However, there were no significant differences between the results in the control group and those of the test group. The bohee tea group's hepatic ADH activity increased by 22.7% compared with that of the positive control group. On the other hand, the hepatic ADH activity of the Drink group increased by 33.6% while that of the A1codex group increased by 20.4%. On the contrary, the bohee tea extract, the hepatic ALDH did not manifest any significant difference as compared with the normal control group. However, its decrease rate was about 16.67% as compared with that of the positive control group. The Drink group, meanwhile, obtained a decrease rate of about 21.59%.

• Journal of Environmental Health Sciences
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• v.30 no.3
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• pp.230-238
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• 2004

The adverse health effects of a number of environment pollutions are related to the formation of free radicals. Induction of antioxidant defensive system in the response to an oxidative attack is an essential element of the cell to survive. CYP2E1 is easily induced by organic solvents and induces continuous formation of reactive oxygen species (ROS). ${\gamma}$-Glutamyltranspeptidase (${\gamma}$GT) plays an important role in glutathione metabolism and xenobiotic detoxification. To evaluate the characteristic of oxidative stress which induces GGT expression and to understand human antioxidant defensive response against oxidative stress induced by CYP2E1, we studied regulation of ${\gamma}$GT enzyme expression in response to various oxidative stresses in human HepG2 cells. The ${\gamma}$GT activity was not modified after exposure of acute oxidative stress inducing agents (ferric nitrilotriacetate, cumene hydroperoxide, ADP-Fe, O-tetradecanoylphorbol-13-acetate, tumor necrosis factor-alpha). To induce continuous exposure of cells to ROS, HepG2 cells were transfected by human CYP2E1 gene transiently. The CYP2E1 activity was verified with chlorzoxazone hydroxylation. Transfection of CYP2E1 showed continuous 60% increase in intracellular ROS and 240 % increase in microsomal ROS. CYP2E1 overexpressing cells showed increased ${\gamma}$GT activity (2.5-fold). The observed enhancement of ${\gamma}$GT activity correlated with a significant increase of ${\gamma}$GT mRNA (2.1-fold). Treatment with antioxidant strongly prevented the increase in ${\gamma}$GT activity. The CYP2E1 overexpression did not modify toxicity index and increased glutathione levels. These results show that continuous exposure of cells to ROS produced by CYP2E1 up-regulates ${\gamma}$GT; This may be one of the adaptive antioxidant responses of cells to oxidative insult. Present study also suggests that the induction of ${\gamma}$GT could be used as a marker of oxidative stress induced by exposure to organic solvents.

• Journal of Periodontal and Implant Science
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• v.35 no.4
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• pp.891-905
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• 2005

The present study was performed to evaluate the effect of tetracycline-HCL on the change of implant surface microstructure according to application time. Implant with pure titanium machined surface. HA-coated surface and TiUniteTM surface were utilized. Implant surface was rubbed with 50mg/ml tetracycline-HCL solution for $\frac{1}{2}min.$, 1min., $1\frac{1}{2}min.$, 2min., and $2\frac{1}{2}min.$ respectively in the test group. Then, specimens were processed for scanning electron microscopic observation. The results of this study were as follows. 1. Both test and control group showed a few shallow grooves and ridges in pure titanium machined surface implants. There were not significant differences between two groups. 2. In HA-coated surfaces, round particles were deposited irregularly. The roughness of surfaces conditioned with tetracycline-HCL was lessened and the cracks were increased relative to the application time. 3. The anodic oxidized surfaces showed the craterous structures. The surface conditioning with tetracycline-HCl didn't influence on its micro-morphology. In conclusion, the detoxification with 50mg/ml tetracycline-HCL must be applied respectively with different time according to various implant surfaces.

• Journal of Periodontal and Implant Science
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• v.38 no.1
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• pp.67-74
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• 2008

Purpose: The aim of this study was to evaluate the effect of Er:YAG laser on microstructure and roughness of $TiO_2$ blasting implant surface. Materials and Methods: Ten $TiO_2$ blasting implant were used in this experiment. One implant was control group, and nine $TiO_2$ blasting implant surfaces were irradiated with Er:YAG laser under 100 mJ/pulse, 140 mJ/pulse, and 180 mJ/pulse condition for 1 min, 1.5 min, and 2 min respectively. Optical interferometer and scanning electron microscopy was utilized to measure roughness and microstructure of specimens. Results: The surface roughness was decreased after Er:YAG laser irradiation in all groups, but there was no significant difference. 100 mJ/pulse and 140 mJ/pulse group did not alter the $TiO_2$ blasting implant surface in SEM study while 180 mJ/pulse group altered the $TiO_2$ blasting implant surface. Implant surfaces showed melting, microfracture and smooth surface in 180 mJ/pulse group. Conclusion: Detoxification of implant surface using Er:YAG laser must be irradiated with proper energy output and irradiation time to prevent implant surface alteration.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.8
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• pp.1107-1112
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• 2011

Over-consumption of alcohol leads to many side-effects such as malnutrition, liver disease, and neuronal disorders and many investigators have tired to identify methods for preventing the side-effects of drinking. In this study, we demonstrated the protective effect of a new food component, SAC-1, containing Hovenia dulcis Thumb and Lonicera caerulea Thumb extract against the side-effects of drinking. We observed that blood alcohol concentration, glutamic oxaloacetate transaminase, lipid peroxidation, and total glutathione level decreased significantly in plasma and liver of mice fed the SAC-1 extract before alcohol intoxication. In particular, SAC-1 had more of a protective effect than that of Hovenia dulcis Thumb extract alone. These results suggest that SAC-1 should further be developed to treat alcohol detoxification and stimulate antioxidative potentials.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.5
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• pp.454-469
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• 2006

Today, there is considerable evidence to support a cause-effect relationship between microbial colonization and the pathogenesis of implant failures. The presence of bacteria on implant surfaces may result in an inflammation of the peri-implant mucosa, and, if left untreated, it may lead to a progressive destruction of alveolar bone supporting the implant, which has been named as peri-impantitis. Several maintenance regimens and treatment strategies for failing implants have been suggested. Recently, in addition to these conventional tools, the use of different laser systems has also been proposed for treatment of peri-implant infections. As lasers can perform excellent tissue ablation with high bactericidal and detoxification effects, they are expected to be one of the most promising new technical modalities for treatment of failing implants. It is introduced that Er,Cr:YSGG laser, operating at 2780nm, ablates tissue by a hydrokinetic process that prevents temperature rise. We studied the change of the titanium implant surface under scanning electron microscopy after using Er,Cr:YSGG laser at various energies, irradiation time. In this study, Er,Cr:YSGG laser irradiation of implant fixture showed different effects according to implant surface. Er,Cr:YSGG laser in TPS surface with RBM not alter the implant surface under power setting of 4 Watt(W) and irradiation time of 30sec. But in TPS surface with $Ca_3P$ coating alter above power setting of 2W and irradiation time of 10sec. TPS surface with RBM showed microfracture in 4W, 30sec and TPS surface with $Ca_3P$ coating showed destruction of fine crystalline structure, melting in excess of 2W, 10sec. We concluded that proper power setting, air, water of each implant surface must be investigated and implant surface must be irradiated under the damaged extent.

• Korean Journal of Health Education and Promotion
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• v.17 no.2
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• pp.57-73
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• 2000

A study on drug abuse of young people who failed in college entrance examinations and preparing the next examination and those enrolled at colleges but trying to transfer to other colleges was conducted from February 3 to May 31, 1999 in order to determine current drug abuse status of them and factors affecting their behavior related to drug abuse. A total of 1,771 people were selected from college entrance preparation institutes in Seoul, Pusan, Taegu, Taejon and Kwangju and interviewed by using questionnaires. The results are summarized as follows; 1. 49.78％ of them experienced drinking, 22.8％ smoking, and 6.7％ drug previously. More males smoked cigarettes than females. The young in the age group of 25 to 29 years old, and the young living in small towns, and subjects who finished junior colleges and those without religions drank more than those in other categories. The subjects in the age group of 20 to 24 years old and those with one parent, and those living in small towns used more drugs than those in other categories. 2. 60.1％ of those with drug using experience used the drug in their or friends' homes. 53.6％ of them used drugs with their friends, junior or senior classmates. 36.6％ of them purchased drugs from drug stores. 76.0％ of them spent their pocket money for buying drugs. 3. The drugs (excluding alcohol and tobacco) they used were bond and butane gas (29.6％), stimulants (20.6％), marijuana 02.0％) LSD (4.8％), cocaine, heroine and opium (4.2％), and others (28.8％). 4. 21.5％ of those with drug using experience had detoxification treatment previously. The ajmor sufferings they experienced were distraction (42.6％), fear 01.7％), and others. 5. 51.0％ of the subjects experienced drug related health education in schools, and 14.6％ had that kind of education through social program. 6. 64.3％ of the subjects got information about drug abuse through mass media, 16.4％ through printed materials, and 11.4％ through public health professionals. 7. The knowledge level of drug abuse was 16.48:1:2.76 points out of 24 (68.6 points out of 100).