• Journal of the Korean Applied Science and Technology
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• v.29 no.1
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• pp.102-107
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• 2012

The recovery of a Pt anode in a PEMFC through 30 ppm $H_2S/H_2$ exposure was evaluated by using a cyclic voltametry(CV) scan. First, the PEMFC unit cell performanc loss was measured three times under an anode feeding with 30 ppm $H_2S/H_2$ for 1hr at $0.5A/cm^2$ of current density. The initial cell performance was $1.16A/cm^2$ at 0.6 V without $H_2S$ poisoning. After first poisoning step for 1hr the cell performance was decrease to $0.77A/cm^2$, and the further poisoning steps decreased up 0.57 V. Finally, the recovery of the cell performance of $H_2S$ poisoned PEMFC was achieved up to 90.3% by applying CV scan. Moreover, we also found out that another possible approach for over 80% recovery of the cell performance of $H_2S$ poisoned anode Pt catalyst layer was to just inject fresh hydrogen into the anode feeding stream.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.3
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• pp.257-261
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• 2000

Integumentary system of the polychaete, Perinezeis aibuhitensis was consisted cuticular, epidermal and dermal layers. Excretory pores opened in cuticular layer, which is covered with epicuticular projections. The hemidesmosomes were observed between supporting cell and basal area of cuticular layer. The epidermal layer was consisted supporting cells and unicellular glands. Supporting cell was relatively larger than the other neighbouring cells, and the nucleus had one to two nucleolus. Cytoplasm of the supporting cell had well-developed intracellular organs such as tonofilaments, mitochondria, rough endoplasmic reticula, free ribosomes and pigment granules of electron dense. The gland cells were reacted with blue in AB-PAS, and classified into the three types such as ${\alpha},\;{\beta}\;and\;{\gamma}$ from the transmission electron microscopic observation. Type ${\alpha}$ gland cell was ovoid and the cytoplasm had well-developed tonofilaments and membrane bounded secretory granules of $0.8{\~}1.5 {\mu}m$ in diameter. Type ${\beta}$ gland cell had a large vacuole and secretory granules of $0.5{\~}0.8 {\mu}m$, which scattered evenly in the cytoplasm. Type ${\gamma}$ gland cell had well-developed endoplasmic reticulum, Golgi auparatus and secretory granules of $0.2{\~}0.3 {\mu}m$ in diameter. The electron density of this granules was the highest among the granules.

• Ocean and Polar Research
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• v.31 no.1
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• pp.121-131
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• 2009

In an effort to better understand the physiological and ecological differences between warm and cold water copepod species in Korean waters using lipid contents and compositions, two species of copepods (Pleuromamma sp. as a warm water species and Neocalanus plumchrus as a cold water species) were collected from the Northwest Pacific and East Sea/Sea of Japan, respectively. The cold water species showed two fold higher lipid contents than the warm water species (11% vs. 5% of dry weight). Wax esters, known as one of the major storage lipid classes, were found to be the dominant lipid class (accounting for 64% of total lipids) in the cold water species, whereas, in the warm water species, phospholipids, which are known as membrane components, were the dominant lipid class (accounting for 43% of total lipids),with a trace amount of the storage lipids as a form of triacylglycerols (${\leq}1%$ of total lipids). With regard to the fatty acid compositions, saturated fatty acids (SAFA), especially 16:0 (about 30% of total fatty acids), were most abundant in the warm water species, whereas the polyunsaturated fatty acids (PUFA), particularly eicosapentaenoic acid (EPA : 20:5(n-3)) (${\geq}16%$ of total fatty acids), were most abundant in the cold water species. Among the neutral fraction of lipids, phytol, originating from the side chain of chlorophyll and indicative of active feeding on phytoplankton, was detected only in the warm water species. Significant quantities of fatty alcohols were detected in cold water species, particularly long-chain monounsaturated fatty alcohols (i.e. 20:1(n-9) and 22:1(n-11)), which are well known to abound in cold water herbivorous copepods. However, only trace amounts of short-chain fatty alcohols were detected in the warm water species. Twelve different kinds of sterols were detected in these copepod species, with cholest-5-en-$3{\beta}$-ol (cholesterol) and cholesta-5, 24-dien-$3{\beta}$-ol (desmosterol) dominating in cold and warm water species, respectively. In addition, for the warm water species (Pleuromamma sp.), we assessed the latitudinal gradients of lipid contents and compositions using samples from three different latitudinal regions (Philippine EEZ, Japan EEZ, and the East China Sea). Although no latitudinal gradients of lipid contents were detected, the lipid compositions, particularly dietary fatty acid markers, varied significantly with the latitude. The findings of this study confirm that the distribution of lipid contents and compositions in copepods may not only indicate their nutritional condition and diet history, but may also provide insights into their living strategies under different environmental conditions (i.e., water temperature, food availability).

• Journal of the Korea Organic Resources Recycling Association
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• v.7 no.2
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• pp.25-34
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• 1999

The effects of copper on the anaerobic degradation of propionate were studied using anaerobic batch reactors. The apparent inhibitory effects of copper on the anaerobic degradation of propionate could be observed from behaviors of intermediates, ultimate methane yield(UMY) and specific methanogenic activity(SMA) There was little inhibition at the concentration of $2.5mg\;Cu^{2+}/L$. Beyond this concentration, the inhibitory effects increased with increasing dose of coppers. The 50% inhibition of UMY and SMA occurred at copper dosage of 33.8 and $24.1mg\;Cu^{2+}/gVSS$, respectively. The inhibitory effect based on the UMY was gradually reduced with the operation time dueprobably to the acclimation of microorganisms and/or binding of the added copper by ligands(and possibly ion exchange sites)contained on the cell membrane and extracellular polymer matrix whereas it based on the SMA might exclude the this phenomena. Therefore, the methodology for interpretation of inhibition data based on the SMA was more accurated than the UMY. There was no inhibitory effect in batch reactors supplemented with sulfate due to an antagonistic action of the sulfate reducing bacteria. Propionate degradation was initially retarded for copper inhibited samples but it gradually degraded afterward. Based on the mass removal considering take into account the propionate to acetate conversion, propionate degradation may appeal more affected than acetate. This result revealed that the hydrogenotrophic methanogens were the most affected by copper.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.4
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• pp.275-288
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• 2009

The Korean government strengthened the environmental polices to manage and enhance Metropolitan Area air quality, and also has enforced "Special Act on Seoul Metropolitan Air Quality Improvement (SASMAQI)" issued in Dec. 2004. Recently government expanded the Seoul Metropolitan Air Quality Management District (SMAQMD) to the outskirts satellite cities of Seoul area through the "Revised Law Draft of SASMAQI". The SMAQMD has been alloted the allowable emission loads to the local governments on the basis of the carrying $PM_{10}$ capacity. However, in order to establish the effective air quality control strategy for $PM_{10}$, it is necessary to understand the corresponding sources which have a potential to directly impact ambient $PM_{10}$ concentration. To deal with the situations, many receptor methodologies have been developed to identify the origins of pollutants and to determine the contributions of sources of interests. The objective of this study was to extensively identify $PM_{10}$ sources and to estimate their contributions at the metropolitan area. $PM_{10}$ samples were simultaneously collected at the 3 semi-industrialized local cities in the Seoul metropolitan area such as Hwasung-si, Paju-si, and Icheon-si sites from April 15 to May 31, 2007. The samples collected on the teflon membrane filter by one $PM_{10}$ cyclone sampler were analyzed for trace metals and soluble ions and samples on the quartz fiber filter by another sampler were analyzed for OC and EC. Source apportionment study was then performed by using a positive matrix factorization (PMF) receptor model. A total of 6 sources were identified and their contributions were estimated in each monitoring site. Contribution results on Hwasung, Paju, and Icheon sites were as follows: 33%, 27%, and 27% from soil source, 26%, 26%, and 21% from secondary aerosol source, 11%, 11%, and 12% from biomass burning, 12%, 6%, and 5% from sea salt, 7%, 15%, and 19% from industrial related source, and finally 11%, 15%, and 16% from mobile and oil complex source, respectively. This study provides information on the major sources affecting air quality in the receptor sites and thus it will help to manage the ambient air quality in the metropolitan area by establishing reasonable control strategies, especially for the anthropogenic emission sources.

• Journal of Nutrition and Health
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• v.1 no.3_4
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• pp.201-205
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• 1968

The authors has observed the histopathologically and histochemically on the effect of the garlic and garlic oil to the liver and kidney of rats. In order to confirm the histochemical changes of the metabolism of polysaccarides, the periodic acid Schiff reaction was applied. The 30 albino adult male rats weighing about 150 grames from the National Institute of Health were housed individualy and devide into 3 experimental groups: Group C: stock diet group Group B: stock diet-garlic group Group A: stock diet-garlic oil group Group C was fed with stock diet only through out this experimental period, Group B was fed with stock diet supplemented with garlic homogenator to be 1%, and Group A was fed with stock diet supplemented with the garlic oil to 0.05%. The garlic oil used in this experiments was extracted by author. And all rats was fed during 10 weeks. The histopathological and histochemical results were shown in each figure. According to the all results, the following concIusions were drawn. 1) In the garlic oil administrated groups, congestion of the sinusoid was subsided and the liberation of the Kupffer's cells were observed. 2) In garlic administrated groups, fatty metamorphosis in hepatic cells, and slight liberation of Kupffer's cells in sinusoidal walls were observed. Connective tissue proliferation and collagen bundle were observed. 3) The connective tissue and blood vessel wall in portal area Were reacted intensely with PAS stain. The hepatic cells Were reacted intensely with PAS stain in control group and moderately or slightly in garlic and garlic oil administrated group. 4) There were no significant differences in collecting and Henle's loops in each groups, but narrowing of lumen of the distal tubules were observed in garlic oil administrated group. 5) The basement membrane of the tubules and the connective tissues of the vessel wall in Kideny were reacted intensely with PAS stain in each groups. In control and garlic administrated groups. the brush border of the proximal tubules were reacted intensely with PAS stain, but epithelium of the Heine's loop, proximal, distal and collecting tubules were reacted moderately. In garlic oil administrated-group, there were tendency of decreasing of PAS stain in each tubules.

• Journal of Nutrition and Health
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• v.46 no.4
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• pp.307-314
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• 2013

Resveratrol (RSV) exerts several beneficial effects on metabolism and metaflammation-related diseases, including diabetes and non-alcoholic fatty liver disease (NAFLD). The purpose of this study is to investigate whether RSV affects pathophysiology of diabetes and NAFLD as well as hepatic autophagy in a rodent model of diet induced obesity (DIO). DIO was induced in a subset of C57BL/6J mice fed a high fat (HF, 45% kcal fat) diet. After six weeks of HF diet treatment, RSV (8 mg/kg/day) was administered via an osmotic pump for a period of four weeks. Therefore, the experimental groups were as follows: 1) lean control (CON), 2) HF diet-induced obese control (HF), and 3) HF_RSV. Body weight and food intake were monitored daily. Fasting glucose, insulin, and adiponectin in serum and lipid profiles in serum and liver were analyzed. In addition, the autophagic process was investigated using transmission electron microscopy (TEM). Body weight and food intake were not affected by RSV treatment. Impaired glucose control accompanied by DIO was recovered with RSV as shown by lower levels of fasting serum glucose and insulin when compared with HF obese controls. In addition, RSV treatment resulted in increased levels of serum adiponectin, however, indices of lipid profile in serum and livers were reduced. Results of TEM analysis showed that a HF diet induced excessive autophagy with the presence of double-membrane autophagosomes, which was ameliorated by RSV. The regulatory effect of RSV on autophagy was confirmed by the altered LC3-II formation, which increased with a HF diet and was decreased by RSV treatment. These results suggest that RSV treatment improves glucose control and lipid profile and these beneficial effects may be mediated by an altered autophagic process.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.6
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• pp.835-842
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• 2016

The phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway plays a crucial role in cancer occurrence by promoting cell proliferation and inhibiting apoptosis. In the present study, we evaluated the effect of a PI3K inhibitor, LY294002, on the chemosensitivity of gastric cancer cells to cordycepin, a predominant functional component of the fungus Cordyceps militaris, in AGS human gastric cancer cells and investigated possible underlying cellular mechanisms. Our results revealed that cordycepin inhibited viability of AGS cells in a concentration-dependent manner and induced apoptosis, as determined by apoptotic cell morphologies and fluorescence-activated cell sorting analysis associated with attenuated activation of the PI3K/Akt signaling pathway. Treatment with cordycepin in combination with a subtoxic concentration of LY294002 enhanced cordycepin-induced cytotoxicity and apoptotic potentials in AGS cells. Sensitization of LY294002 to cordycepin-induced apoptosis was accompanied by activation of caspases (caspases-3, -8, and -9) and was concomitant with poly(ADP-ribose) polymerase cleavage. Moreover, LY294002 up-regulated pro-apoptotic Bax and enhanced truncation of Bid in cordycepin-treated AGS cells, which was connected with increased loss of mitochondrial membrane potential and release of cytochrome c from mitochondria to the cytosol. Taken together, these results indicate that inhibition of the PI3K/Akt signaling pathway could augment cordycepin-induced apoptosis in human gastric cancer cells by up-regulating caspase activity through mitochondrial dysfunction.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.5287-5291
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• 2013

The human papilloma virus (HPV) causes skin and mucous membrane infections. It crosses from one person to another by skin-to-skin contact, such as sexual contact. There are more than 100 types of HPV that can influence different parts of the body. Some types of HPV can cause cancer (such as cervical or anal cancer) and others can cause warts (such as genital or plantar warts). HPV infection is one of the most common sexually transmitted infections (STIs) in Iran and around the world. Considerable molecular evidence suggests a role for human papilloma virus (HPV) in the pathogenesis of carcinoma. Epidemiological studies on human papilloma viruses (HPVs) infections in general population are critical for the performing of health policy guidelines for developing the strategies to hinder the primary and secondary different cancer. In different parts of Iran, there is a lack of population-based studies to determine the prevalence of HPV in the general population. The aim of this population-based study was therefore to report the prevalence ratse of HPV types among Iranian patients. To study the risk of human papilloma virus (HPV) infection, we managed a retrospective study in Kerman province, southeast of Iran. For this purpose, 410 patients tested for the presence of HPV DNA using PCR and INNo-Lipa assays. HPV DNA was detected in 108 out of 410 patients (26.34%), while it was not detected in any of the control group samples. Patients included 23 (21.1%) males and 86 (78.8%) females. HPV type 6 was the most common (49%) followed by HPV type 16 (10.1%), and also HPV type11 (9.2%). The prevalence of HPV in Iran is comparable to those reported in other regions of the world. In a similar manner, it seems that HPV types 6, 16 and11 are the most common types in Kerman. Additional studies on larger group of patients, particularly in those with pre-invasive forms of disease, are needed to explain the roles of different HPV types in this location of Iran.

• Journal of Acupuncture Research
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• v.19 no.2
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• pp.211-220
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• 2002

Objective : This study was undertaken to determine whether Scutellaria baicalensis Georgi extract (SbG) exerts the protective effect against oxidant-induced alterations in organic cation transport in the renal proximal tubule. Methods : Organic cation transport was estimated by examining alterations in tetraethylammonium (TEA) uptake in rabbit renal cortical slices. The slices were treated with 0.2 mM tBHP for 60 min at $37^{\circ}C$. tBl-IP caused an inhibition in TEA uptake by renal cortical slices. Such an effect was accompanied by depressed Na+-K+-ATPase activity and ATP depletion. Result : SbG prevented tBHP-induced inhibition of TEA uptake in a dose-dependent manner at the concentration ranges of 0.05-0.1%. SbG also prevented H2O2-induced reduction in TEA uptake. tBHP-induced inhibition of Na+-K+-ATPase activity and ATP depletion were significantly prevented by 0.05% SbG. Oxidants increased LDH release, which was blocked by SbG. Oxidants caused a significant increase in lipid peroxidation and its effect was prevented by SbG. Conclusion : These results suggest that SbG prevents oxidant-induced alterations in organic cation transport in rabbit renal cortical slices. Such protective effects of SbG may be attributed to inhibition of peroxidation of membrane lipid.