• Current Photovoltaic Research
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• v.5 no.1
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• pp.15-19
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• 2017

The fossil fuel power consumption generates $CO_2$, which causes the problems such as global warming. Also, the increase in energy consumption has accelerated the depletion of the fossil fuels, and renewable energy is attracting attention. Among the renewable energies, the solar energy gets a lot of attention as the infinite clean energy source. But, the supply level of solar cell is insignificant due to high cost of generation of electric power in comparison with fossil fuels. Thus several researchers are recently doing the research on ultra-low-cost solar cells. Also, $Cu_2O$ is one of the applied materials as an absorption layer in ultra-low-cost solar cells. Cuprous oxide ($Cu_2O$) is highly desirable semiconductor oxide for use in solar energy conversion due to its direct band gap ($E_g={\sim}2.1eV$) and a high absorption coefficient that absorbs visible light of wavelengths up to 650 nm. In addition, $Cu_2O$ has several advantages such as non-toxicity, low cost and can be prepared with simple and cheap methods on large scale. In this work, we fabricated the $Cu_2O$ thin films by reactive sputtering method. The films were deposited with a Cu target with variable parameters such as substrate temperature, rf-power, and annealing condition. Finally, we confirmed the structural properties of thin films by XRD and SEM.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2943-2948
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• 2012

Arsenic exposure is a serious health hazard worldwide. We have previously established that it may result in immune suppression by upregulating Th2 cytokines while downregulating Th1 cytokines and causing lymphocytic death. Treatment modalities for arsenic poisoning have mainly been restricted to the use of chelating agents in the past. Only recently have combination therapies using a chelating agent in conjunction with other compounds such as anti-oxidants, micronutrients and various plant products, been introduced. In the present study, we used T11TS, a novel immune potentiating glycopeptide alone and in combination with the sulfhydryl-containing chelator, mono-iso-amyl-dimarcaptosuccinic acid (MiADMSA) as a therapeutic regimen to combat arsenic toxicity in a mouse model. Results indicated that Th1 cytokines such as TNF-${\alpha}$, $IFN{\gamma}$, IL12 and the Th2 cytokines such as IL4, IL6, IL10 which were respectively downregulated and upregulated following arsenic induction were more efficiently restored to their near normal levels by T11TS alone in comparison with the combined regimen. Similar results were obtained with the apoptotic proteins studied, FasL, BAX, BCL2 and the caspases 3, 8 and 9, where again T11TS proved more potent than in combination with MiADMSA in preventing lymphocyte death. The results thus indicate that T11TS alone is more efficient in immune re-establishment after arsenic exposureas compared to combination therapy with T11TS+MiADMSA.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.11
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• pp.4819-4823
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• 2016

Bckground: Adjuvant radiation therapy is commonly administered following breast-conserving surgery for breast cancer patients. Hypofractionated radiotherapy can significantly reduce the waiting time for radiotherapy, working load on machines, patient visits to radiotherapy departments and medical costs. Material/Methods: Fifty-two patients with operable breast cancer (pT1-3pN0M0) who underwent breast conservation surgery in Tehran Cancer Institute during January 2011 to January 2012, were randomly assigned to undergo radiotherapy in two arms (hypofractionated radiotherapy arm with 30 patients, dose 42.5 Gy in 16 fractions; and conventional radiotherapy arm with 22 patients, dose 50 Gy in 25 fractions). W compared these two groups in terms of overall survival, locoregional control, late skin complications and cosmetic results. Results: At a median follow-up of 52.4 months (range: 0-64 months), the follow-up rate was 82.6%. Overall, after 60 months, there was no detectable significant differences between groups regarding cosmetic results (p = 0.857), locoregional control or survival. Conclusions: The results confirm that hypofractionated radiotherapy with a subsequent boost is as effective as conventional radiotherapy, is well-tolerated and can be used as an alternative treatment method following breast conservation surgery.

• The Korean Journal of Physiology and Pharmacology
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• v.4 no.3
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• pp.177-183
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• 2000

We examined the neurotoxic effects of 3 glutathione (GSH) depletors, buthionine sulfoximine (BSO), diethyl maleate (DEM) and phorone, under the presence of trolox, cycloheximide (CHX), pyrrolidine dithiocarbamate (PDTC) or MK-801 in primary mouse cortical cell cultures. All three depletors induced neuronal death in dose and exposure time dependent manner, and decreased total cellular GSH contents. The patterns of the neuronal death and the GSH decrements were dependent on the individual agents. DEM $(200\;{\mu}M)$ induced rapid and irreversible decrement of the GSH. BSO (1 mM) also decreased the GSH irreversibly but the rate of decrement was more progressive than that of DEM. Phorone (1 mM) reduced the GSH content to 40% by 4 hr exposure, that is comparable to the decrement of BSO, but the GSH recovered and reached over the control value by 36 hr exposure. BSO showed a minimal neurotoxicity $(0{\sim}10%)$ at the end of 24 hr exposure, but marked neuronal cell death at the end of 48 hr exposure. The BSO (1 mM)-induced neurotoxicity was markedly inhibited by trolox or CHX and partially attenuated by MK-801. DEM induced dose-dependent cytotoxicity at the end of 24 hr exposure. Over the doses of $400\;{\mu}M,$ glial toxicity also appeared. DEM $(200\;{\mu}M)-induced$ neurotoxicity was markedly inhibited by trolox or PDTC. Phorone (1 mM) induced moderate neurotoxicity (40%) at the end of 48 hr exposure. Only CHX showed significant inhibitory effect on the phorone-induced neurotoxicity. These results suggest that the GSH depletors induce neuronal injury via different mechanisms and that GSH depletors should be carefully employed in the researches of neuronal oxidative injuries.

• The Korea Journal of Herbology
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• v.31 no.1
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• pp.77-82
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• 2016

Objectives : The study was designed to observe the effect of Polygalae Radix Preparata Cum Glycyrrhizae Radix on 4-Hydroxynonenal (4-HNE)-induced apoptosis in PC-12 cell.Methods : A cytotoxic test on Polygalae Radix Preparata Cum Glycyrrhizae Radix (PG) was conducted and another MTT assay was conducted to observe the cytoprotective effect against 4-HNE that cause oxidative stress. In addition, in order to observe the expression of Bax, Bcl-2, Caspase-3 and TNF-α protein involved with apoptosis, western blot was conducted.Results : The groups treated with 25 ㎍, 50 ㎍ and 100 ㎍ of PG water extract had no toxicity for PC-12 cell. The groups treated with 25 ㎍, 50 ㎍ and 100 ㎍ of PG water extract showed a significant increase of cell survival rate in comparison with the control group injected by only 4-HNE. The groups treated with 25 ㎍ and 50 ㎍ of PG water extract showed a significant supression on increase of Bax protein expression in the control group. The group treated with 100 ㎍ of PG water extract showed a significant promotion on decrease of Bcl-2 protein expression in the control group. The group treated with 50 ㎍ of PG water extract showed a significant supression on increase of Caspase-3 protein expression in the control group. The group treated with 25 ㎍ of PG water extract showed a significant supression on increase of TNF-α protein expression in the control group.Conclusions : These results suggest that Polygalae Radix Preparata Cum Glycyrrhizae Radix is effective in reducing apoptosis by 4-HNE-dameged cell.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.10
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• pp.4239-4243
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• 2014

Background: This study investigated the influence of curcumin on HOX transcript antisense RNA (HOTAIR)-mediated migration of cultured renal cell carcinoma (RCC) cells. Materials and Methods: Five RCC cell lines (769-P, 769-P-vector, 769-P-HOTAIR, 786-0, and Kert-3 ) were maintained in vitro. The expression of HOTAIR mRNA was determined by quantitative real-time PCR and cell migration was measured by transwell migration assay. The effects of different concentrations of curcumin (0 to $80{\mu}mol/L$) on cell proliferation was determined by the CCK-8 assay and influence of non-toxic levels (0 to $10{\mu}M$) on the migration of RCC cells was also determined. Results: Comparison of the 5 cell lines indicated a correlation between HOTAIR mRNA expression and cell migration. In particular, the migration of 769-P-HOTAIR cells was significantly higher than that of 769-P-vector cells. Curcumin at $2.5-10{\mu}M$ had no evident toxicity against RCC cells, but inhibited cell migration in a concentration-dependent manner. Conclusions: HOTAIR expression is correlated with the migration of RCC cells, and HOTAIR may be involved in the curcumin-induced inhibition of RCC metastasis.

• The Journal of Dong Guk Oriental Medicine
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• v.1
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• pp.209-236
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• 1992

The microculture XTT antiviral assay method is used to quantitate HIV-1 induced cytopathic effects as modulated by test substances. This relatively simple assay facilitated the safe and rapid determination of in vitro antiviral activity of selected chemicals as well as direct cytotoxicity. This experiment also confirmed that this system measures infection and subsequent viral replication in target cells and XTT formazan formations correlated with the accumulation of extracellular virions, as measured by quantitative HIV-1 induced syncytium foramtion. The present results with Glycyrrhizin using this in vitro culture system demonstrated that effective dose, EC50(the concentration at which increases XTT formazan production in infected cultures to 50% of that in untreated, uninfected controls) was 250ml. As comparison, AZT was included in this experiment and demonstrated that EC50 AZT of was 0.05g/ml, approximately 5,000 times more potent than Glycyrrhizin based on EC50 ratio's alone. However, this potency is limited by severe cytotoxicity of AZT, while Glycyrrhizin is approximately 16 times less toxic(IC50 of Glycyrrhizin 800 and AZT 51 g/ml). While AZT's anti-HIV-1 viral activity is mediated by inhibition of reverse transcriptase of the virus, Glycyrrhizin faild to demonstrate any inhibitory activity against reverse transcriptase. Further study is necessary in order to understand the precise mechanisms of Glycyrrhizin action against HIV-1 viruses. Althouth Glycyrrhizin is less effective antiviral agent than AZT, much less toxicity of Glycyrrhizin is desirable in terms of chronic treatment. Combination treatment of AZT and Glycyrrhizin may be therapeutically beneficial. Clinical effectiveness of two drug combination therapy for AIDS patient is unknown at this time. However, this experimental investigation presents the scientific rational basis for such therapeutic approach.

• Journal of Soil and Groundwater Environment
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• v.16 no.2
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• pp.12-29
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• 2011

Risk-based screening levels (RBSLs) of some pollutants for residential adults were derived with risk assessment tools developed by United States Environmental Protection Agency (USEPA), American Society for Testing and Materials (ASTM), and Korea Ministry of Environment (KMOE) and compared each other. To make the comparison simple, ingestion of soil, dermal contact with soil, outdoor inhalation of vapors, indoor inhalation of vapors, and inhalation of soil particulates were chosen as exposure pathways. The results showed that the derived RBSLs varied for every exposure pathway. For direct exposure pathways (i.e., ingestion of soil and dermal contact with soil), the derived RBSLs varied mainly due to the different default values for exposure factors and toxicity data. When identical default values for the parameters were used, the same RBSLs could be derived regardless of the assessment tools used. For inhalation of vapors and inhalation of soil particulates, however, different analysis methods for cross-media transfer rates were used and different assumptions were established for each tool, identical RBSLs could not be obtained even if the same default values for exposure factors were used. Especially for inhalation of soil particulates pathway, screening level derived using KMOE approach (most conservative) was approximately 5000~10000 times lower than the screening level derived using ASTM approach (least conservative). Our results suggest that, when deriving RBSL using a specific tool, it is a prerequisite to technically review the analysis methods for cross-media transfer rates as well as to understand how the assessment tool derives the default values for exposure factors.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.15 no.1
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• pp.27-35
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• 2005

This study was carried out to evaluate the characteristics of petroleum refinery workers' exposure to organic solvents. Exposure assessment was conducted by full shift-based long term personal sampling(TWA-P) and task-based short term personal sampling(STEL-P) strategy. Major organic solvents that workers can be exposed are various, varying from C3~C12, and this study focused on 11 kinds including benzene, considering toxicity and concentration level. In comparison with two sampling results, STEL-P shows a significant(p<0.001) excess of exposure level rather than TWA-P. As the potential risk index for benzene is calculated as 16, benzene should be set the highest priority for control in petroleum refinery industry. The tasks with the highest benzene exposure level were de-watering(AM;99.8 ppm), draining(AM;19.6ppm), sampling(AM;16.2ppm), and manual gauging(AM;15.02ppm). Petroleum refinery workers' exposure pattern to organic solvents differs by tasks performed, and some task has a high risk of temporary extreme exposure. Therefore, traditional 8-hour TWA sampling strategy have possibility of underestimation of exposure level of workers in petroleum refinery.

• Korean Journal of Pharmacognosy
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• v.40 no.3
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• pp.205-212
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• 2009

Antitumor activity of Korean mistletoe extract (KM-110) and European commercial mistletoe preparation (Helixor) was investigated. KM-110 showed the cytotoxic effect that it is high for various tumor cell lines and normal splenocytes in comparison with Helixor. Administration of two mistletoe extracts ($100{\mu}g$) to mice did not show any significant changes on the level of glutamic-oxaloacetic transaminase (GOT), glutamic-pyruvate transaminase (GTP), blood creatinine (CRE) and blood urea nitrogen (BUN) in sera. The culture supernatant of macrophages stimulated with KM-110 inhibited effectively tumor growth whereas Helixor had little effect. Administration of KM-110 or Helixor resulted in a effective inhibition of lung metastasis after the i.v. inoculation of colon 26-M3.1 lung carcinoma, B16-BL6 melanoma and L5178Y-ML25 lymphomas. In all cases, the mice treated with KM-110 showed more effective anti-tumor metastatic activity than the mice of Helixor. These results suggest that Korean mistletoe extracts, KM-110 might be used as an alternative methods having antitumor activity like European mistletoe preparation, Helixor.