• BMB Reports
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• v.36 no.1
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• pp.82-94
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• 2003

Although debates still exist whether Helicobacter pylori infection is really class I carcinogen or not, H. pylori has been known to provoke precancerous lesions like gastric adenoma and chronic atrophic gastritis with intestinal metaplasia as well as gastric cancer. Chronic persistent, uncontrolled gastric inflammations are possible basis for ensuing gastric carcinogenesis and H. pylori infection increased COX-2 expressions, which might be the one of the mechanisms leading to gastric cancer. To know the implication of long-term treatment of antiinflammatory drugs, rebamipide or nimesulide, on H. pylori-associated gastric carcinogenesis, we infected C57BL/6 mice with H. pylori, especially after MNU administration to promote carcinogenesis and the effects of the long-term administration of rebamipide or nimesulide were evaluated. C57BL/6 mice were sacrificed 50 weeks after H. pylori infection. Colonization rates of H. pylori, degree of gastric inflammation and other pathological changes including atrophic gastritis and metaplasia, serum levels and mRNA transcripts of various mouse cytokines and chemokines, and NF-${\kappa}B$ binding activities, and finally the presence of gastric adenocarcinoma were compared between H. pylori infected group (HP), and H. pylori infected group administered with long-term rebamipide containing pellet diets (HPR) or nimesulide mixed pellets (HPN). Gastric mucosal expressions of ICAM-1, HCAM, MMP, and transcriptional regulations of NF-${\kappa}B$ binding were all significantly decreased in HPR group than in HP group. Multi-probe RNase protection assay showed the significantly decreased mRNA levels of apoptosis related genes and various cytokines genes like IFN-$\gamma$, RANTES, TNF-$\alpha$, TNFR p75, IL-$1{\beta}$ in HPR group. In the experiment designed to provoke gastric cancer through MNU treatment with H. pylori infection, the incidence of gastric carcinoma was not changed between HP and HPR group, but significantly decreased in HPN group, suggesting the chemoprevention of H. pylori-associated gastric carcinogenesis by COX-2 inhibition. Long-term administration of antiinflammatory drugs should be considered in the treatment of H. pylori since they showed the molecular and biologic advantages with possible chemopreventive effect against H. pylori-associated gastric carcinogenesis. If the final concrete proof showing the causal relationship between H. pylori infection and gastric carcinogenesis could be obtained, that will shed new light on chemoprevention of gastric cancer, that is, that gastric/cancer could be prevented through either the eradication of H. pylori or lessening the inflammation provoked by H. pylori infection in high risk group.

• Journal of Chest Surgery
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• v.34 no.11
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• pp.823-830
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• 2001

Background: Paraplegia is a serious complication of thoracic or thoracoabdominal aortic operations, which is related to ischemic injury of the spinal cord induced by low perfusion pressure during cross clamping of the aorta. Ischemic preconditioning of heart or brain with reversible sublethal ischemic injury induces resistance to subsequent lethal ischemia. The aim of this study is to investigate whether ischemic tolerance could be induced by the preconditioning of the spinal cord using swine model. Material and Method: The animals were randomly assigned to three groups: sham group(n=3), control group(n=6) and pre-conditioning group(n=8). In the sham group, we performed the left thoracotomy only without any ischemic injury. In the preconditioning group, the swine received reversible spinal cord ischemic injury by aortic clamping for 20 minutes, whereas control group had no previous aortic cross- clamping. Forty-eight hours later, the aorta was clamped for 30 minutes in both groups. Neurological examination was done 24 hours later, then the animals were euthanized for histopathology and malonedialdehyde(MDA) spectrophotometry assay of the spinal cord. Result: Statistically significant difference in neurological outcome was observed between the control and preconditioning groups at 24 hours after ischemic injury. The incidence of paraplegia and severe paresis was 100% in the control group, and 62.5% in the preconditing group(p=0.028). There was no statistically significant difference in histopathology and MDA assay of the ischemic spinal cord between these two groups with borderline statistical difference in MDA assay(p=0.0745). Conclusion: In the present swine study, ischemic preconditioning could induce tolerance against 30 minute ischemic insult of the spinal cord, although the animals did not completely recover(stand-up or walk). We expect that combining this preconditioning with other currently existing protection methods might lead to a synergistic effect, which warrants further investigation.

• Journal of the Korean Applied Science and Technology
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• v.37 no.2
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• pp.153-161
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• 2020

Arthrospira platensis is the oldest marine microalgae on the planet, is said to contain most of the nutrients needed by the human body. It's components are reported to contain a large amount of various substances such as phycocyanin, chlorophyll and β-carotene, and are known to have an aging and whitening effect. In this study, UVB-induced reactive oxygen species reduction efficacy and antioxidant activity of spirulina purified water extract were investigated. effect was confirmed by measuring DPPH radical scavenging activity, FRAP reducing power and ABTS⁺ radical scavenging activity of 0.05, 0.10, 0.50 1.0 mg/mL of spirulina purified water extract. The coagulation rate, hatching rate and heart rate toxicity were measured by treating spirulina purified water extract with 0.05, 0.10, 0.50 mg/mL concentration using Zebrafish, an alternative experimental animal model. UVB-induced ROS measurement was treated with spirulina extract at 0.05, 0.10, 0.50 mg/mL concentration, and then stained with DCFH-DA to confirm the inhibitory effect of ROS. As a result of measuring antioxidant effect, DPPH, FRAP and ABTS⁺ showed concentration-dependent antioxidant effects in comparison with ascorbic acid. and measuring the coagulation rate, hatching rate, and heart rate using Zebrafish, an alternative experimental animal, it was confirmed that there was no toxicity in 0.05 and 0.10 mg/mL except 0.5 mg/mL compared to the control group. The ROS scavenging activity of UVB-induced zebrafish showed higher ROS reduction than the positive control. The results of this study suggest that spirulina and purified water extracts are valuable for UV and skin protection cosmetics.

• Journal of Korean Society for Atmospheric Environment
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• v.33 no.4
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• pp.377-392
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• 2017

A set of BFM (Brute Force Method) simulations with the CMAQ (Community Multiscale Air Quality) model were conducted in order to estimate self-contributions and conversion rates of PPM (Primary $PM_{2.5}$), $NO_x$, $SO_2$, $NH_3$, and VOC emissions to $PM_{2.5}$ concentrations over the SMA (Seoul Metropolitan Area). CAPSS (Clean Air Policy Support System) 2013 EI (emissions inventory) from the NIER (National Institute of Environmental Research) was used for the base and sensitivity simulations. SCCs (Source Classification Codes) in the EI were utilized to group the emissions into area, mobile, and point source categories. PPM and $PM_{2.5}$ precursor emissions from each source category were reduced by 50%. In turn, air quality was simulated with CMAQ during January, April, July, and October in 2014 for the BFM runs. In this study, seasonal variations of SMA $PM_{2.5}$ self-sensitivities to PPM, $SO_2$, and $NH_3$ emissions can be observed even when the seasonal emission rates are almost identical. For example, when the mobile PPM emissions from the SMA were 634 TPM (Tons Per Month) and 603 TPM in January and July, self-contributions of the emissions to monthly mean $PM_{2.5}$ were $2.7{\mu}g/m^3$ and $1.3{\mu}g/m^3$ for the months, respectively. Similarly, while $NH_3$ emissions from area sources were 4,169 TPM and 3,951 TPM in January and July, the self-contributions to monthly mean $PM_{2.5}$ for the months were $2.0{\mu}g/m^3$ and $4.4{\mu}g/m^3$, respectively. Meanwhile, emission-to-$PM_{2.5}$ conversion rates of precursors vary among source categories. For instance, the annual mean conversion rates of the SMA mobile, area, and point sources were 19.3, 10.8, and $6.6{\mu}g/m^3/10^6TPY$ for $SO_2$ emissions while those rates for PPM emissions were 268.6, 207.7, and 181.5 (${\mu}g/m^3/10^6TPY$), respectively, over the region. The results demonstrate that SMA $PM_{2.5}$ responses to the same amount of reduction in precursor emissions differ for source categories and in time (e.g. seasons), which is important when the cost-benefit analysis is conducted during air quality improvement planning. On the other hand, annual mean $PM_{2.5}$ sensitivities to the SMA $NO_x$ emissions remains still negative even after a 50% reduction in emission category which implies that more aggressive $NO_x$ reductions are required for the SMA to overcome '$NO_x$ disbenefit' under the base condition.

• The Korean Journal of Pharmacology
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• v.30 no.3
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• pp.321-330
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• 1994

The protective effect of 'ischemic preconditioning (PC)' on ischemia-reperfusion injury of heart has been reported in various animal species, but without known mechanisms in detail. In an attempt to investigate the cardioprotective mechanism of PC, we examined the effects of PC on the myocardial oxidative injuries and the oxygen free radical production in the ischemia-reperfusion model of isolated Langendorff preparations of rat hearts. PC was performed with three episodes of 5 min ischemia and 5 min reperfusion before the induction of prolonged ischemia (30 min)-reperfusion(20 min). PC prevented the depression of cardiac function (left ventricular pressure x heart rate) observed in the ischemic-reperfused heart, and reduced the release of lactate dehydrogenase during the reperfusion period. On electron microscopic pictures, myocardial ultrastructures were relatively well preserved in PC hearts as compared with non-PC ischemic-reperfused hearts. In PC hearts, lipid peroxidation of myocardial tissue as estimated from malondialdehyde production was markedly reduced. PC did not affect the activity of xanthine oxidase which is a major source of oxygen radicals in the ischemic rat hearts, but the myocardial content of hypoxanthine (a substrate for xanthine oxidase) was much lower in PC hearts. It is suggested from these results that PC brings about significant myocardial protection in ischemic-reperfused heart and this effect may be related to the suppression of oxygen free radical reactions.

• Korean Journal of Microbiology
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• v.48 no.2
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• pp.109-115
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• 2012

Helicobacter pylori is an important factor of chronic gastritis, digestive ulcer, and stomach cancer. CagL, a virulence factor of H. pylori, is well-known as a pilus protein which acts as adhesion to host cell and a component of Type 4 secretion system. In this study, we evaluated the protective response of recombinant CagL protein (rCagL) using Mongolian gerbil animal model for H. pylori infection. The cagL gene was cloned from 26695 H. pylori followed by over-expression and purification of the protein in E. coli. Mongolian gerbils were immunized with rCagL protein mixed with aluminum adjuvant via intramuscular injections once a week during 4 weeks. At a week after the last immunization, the Mongolian gerbils were administrated with H. pylori 7.13 strain into the stomach and sacrificed to measure antibody titer on rCagL by ELISA and bacterial colonization in the stomach, and to examine the histopathological changes and cytokine expression at 6 week after challenge. Antibody titers on recombinant protein were significantly increased from a week after the first immunization. There was no significant change of the number of bacterial colony between control group and immunized group. The relative stomach weight was significantly decreased in immunized group, but the significant change of histopathological assessment was not observed in the stomach. Cytokine expression such as IL-$1{\beta}$ and KC also was not significantly different between control and immunized groups. These results indicate that rCagL could effectively induce the formation of the specific IgG antibodies. However, bacterial colonization and histopathological lesions could not be inhibited by the immunization in the stomach, indicating not enough protection against H. pylori infection. We consider that along with CagL other adequate antigens could be needed stimulating immune response and inducing protective effects against gastric disease, and also a better adjuvant could be considered.

• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.452-455
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• 2006

The in vitro cytoprotective and anti-oxidative effects of ursodeoxycholic acid, a major active compound from bear's gall were investigated in mouse brain microglia. In the present study, we wished to scrutinize the potential role of UDCA as an anti-neurodegenerative agent in neurodegenerative disease such as Alzheimer's disease. This concept was supported by the multiple preliminary studies in which UDCA has an anti-inflammatory effect in microglial cells. In the study, we found that $7.5\;{\mu}g/mL$ UDCA was effective in the protection of cells from $H_2O_2$ damage, a reactive oxygen, and the resuIt was coincided with the anti-apoptotic effect in DAPI staining. Moreover, the metal-catalyzed oxidation study showed that UDCA has antioxidant effect as much as ascorbic acid at $50{\sim}100\;{\mu}g/mL$. In conclusion, these study results suggested that neuro-degenerative diseases such as Alzheimer's disease probably caused by over-expressed beta amyloid peptide in elderly people can be controled by UDCA through an anti-inflammatory, anti-oxidative and anti-apoptotic effect. The evidences showed in the study may be references for more in-depth in vivo and clinical studies for a candidate of anti-neurodegenerative therapy in the near future.

• Childhood Kidney Diseases
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• v.6 no.2
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• pp.169-177
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• 2002

Purpose: Hypertension accelerates the progression of chronic renal disease, whether it results from, or causes, the renal disease. Therefore, the control of hypertension is one of the important factors that retard the rate of renal deterioration. We compared the effects of different antihypertensive agents on renal function and glomerular morphology In subtotal nephrectomized rats. Materials and methods: After induction of chronic renal failure with 5/6 nephrectomy, the rats were divided into three groups; control group (Group C), enalapril group (Group E), and nicardipine group (Group N). Systolic blood pressure was measured by tail cuff method every 4 weeks until 12 weeks after nephrectomy. At 12 weeks after nephrectomy, all rats were placed in metabolic cages for 24 hour urine collections to measure urinary protein and creatinine excretion. After urine collection and blood sampling for serum creatinine, all rats were sacrificed. The renal tissue was processed for morphometric study with light microscope and electron microscope. Results: 1. The blood pressure of Group C increased progressively, but both enalapril and nicardipine prevented the development of hypertension, and the two drugs were equally effective in maintaining normal blood pressure throughout the study. 2. Twenty-four hour urinary protein excretion was lower in Group E compared to Group C and Group N 3. Mesangial expansion score in both treated groups were significantly lower than the control group. Mean glomerular volume in Group E was significantly reduced compared to Group C and Group N. There was no significant difference in mean glomerular volume between Group C and Group N. 4. There was no significant difference in podocyte structural changes, estimated by filtration slit length density, among control, enalapril and nicardipine treated groups. Conclusion: Control of hypertension with enalapril or nicardipine afforded considerable protection from mesangial expansion in the rat remnant kidney model. But protein excretion and glomerular growth were significantly reduced in Group E compared to Group N. There was no significant difference in podocyte structural changes among the 3 groups.

• The Korean Journal of Physiology
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• v.3 no.2
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• pp.9-16
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• 1969

It is well known that a number of -SH and -SS containing substances afford a certain measure of protection against radiation effects in many biological systems, and it is conceivable that inherent -SH levels in Ehrlich ascites tumour (ELD)cells may be of decisive improtance with respect to the development of cellular radiation injury. So far, little effort has been directed to elucidate the changes in levels of different -SH and -SS groups in ELD cells when the tumour-bearing whole animal was subjected to the sublethal dose of X-irradiation. The present study was designed to bring some lights in the possible changes of and relationship between various sulfhydryl levels, such as P-SH, NP-SH and NP-SS, as well as the content of protein and cell volume of ELD cells, after subjecting the ELD mice to 1,200 r of X-irradiation. The animals used in this experiment were all mixed bred mice of $20{\sim}25\;gm$ in body weight (approximately 2 months old) irrespective of sex. 12 mice in one experiment were inoculated intraperitoneally with 0.2 ml of ascites tumour cells $(2{\times}10^6\;cells)$, and on the 7th day of the tumour growth, they were X-irradiated with 1,200 r, using the conventional X-ray machine under the following conditions: 200 Kv at 15 mA, 0.5 mm Cu filter, target-skin distance: 50 cm. Radiation dose was measured with the the Philip integrating dosimeter. At 24, 36, 48 and 60 hours after the X-irradiation, the mice were killed by cervical dislocation, and the tumours were taken out. Freshly withdrawn ascites tumours were placed in ice, and immediately the cell concentration was measured with the Coulter Cell Counter (Model B), and the hematocrit of the tumour cells were also determined. Cell volume was thus calculated by the cell concentration and hematocrit value. P-SH content of ELD cells was measured potentiometrically according to the method of Calcutt & Doxey, and NP-SH and NP-SS contents were measured spectrophotometrically by the method described by Ellman. Protein content of ELD cells was determined with the Folin phenol reagent by Lowry et al. Altogether, 48 experimental mice were used, and 12 mice with the only exception of X-irradiation were used as the control. Results obtained indicate that the contents of all the cellular sulfhydryl groups as well as cell volume and protein content of the ELD cells increase significantly as time progresses after the sub-lethal X-ray dose of 1,200 r was given and that all the increase is in a lineal fashion. The regression lines of the relative values, (i. e., taking each control value as 1) of all the values obtained, and the regression lines of cell volume, protein and NP-SH are identical, whereas those of NP-SS and P-SH appear to be widely seperated. However, the difference of those two lines (NP-SS & P-SH) were found to be not significant statistically (p>0.05). Therefore, it can be concluded from the above results that all the values examined increase in a lineal fashion with no statistically significant difference among them. Also, with the radiation dose of 1,200 r, the ELD cell becomes enlarged and swollen progressively up to 60 hours post-irradiation and it becomes more than two times of the original normal size at 60 hours after the irradiation, and up to this stage, it seems apparent that the cell division has been slow due to the X-irradiation applied in this experiment. It is well understandable that the contents of NP-SH, NP-SS, P-SH and protein of the ELD cells increase in parallel with the increase of the cell volume by the X-ray does used, but it also seems interesting to note that all the cellular substances tested show no appreciable difference in the pattern of increase.

• Journal of Animal Science and Technology
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• v.49 no.6
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• pp.857-870
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• 2007

This study was conducted to investigate the relationship between the socio-demographic factors and the Korean consumers’ palatability evaluation and to collect the sensory information for development of prediction palatability model of Hanwoo beef. Ten cuts〔Abjin (short plate), Bosup (top sirloin), Cheggt (striploin), Dngsim (loin), Guri (chuck tender), Hongduke (eye of round), Moksim (chuck roll), Sulgit (bottom round), Udoon (top round), Yangi (brisket)〕 were separated from 10 Hanwoo bulls beef(～24 months old) and prepared with the same manner for 3 different cooking methods such as boiling, grilling and roasting. The cooked beef samples were served to 650 consumers recruited from Seoul, Joongbu, Honam and Youngnam locations and evaluated tenderness, juiciness, flavor and overall acceptability. The living location, age, gender, occupation, eating habit and cut were significantly related with the sensory properties when bull beef were cooked as boiled cooking(p<0.05). In grill cooking, only occupation, income and cut had the significant effect on the overall acceptability of Hanwoo bull beef(p<0.01). When bull beef were cooked as Korean traditional roast cooking, consumer’s sensory properties were significantly different by the living location, age, occupation, income, eating habit of consumers and cut(p<0.05). Also, results from the principal component analysis showed that palatability scores of Korean consumers were decided with different contribution scores of tenderness, juiciness, flavor and overall acceptability of cut depending on cooking methods. In conclusion, Korean consumers’ palatability for Hanwoo bull beef were related with the socio-demographic factors and the sensory results were different by cut and cooking methods.