• Title/Summary/Keyword: Dose-response

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UVB-Shielding Effects of para-Coumaric Acid (파라-쿠마린산의 자외선B 차단 효과)

  • Song, Kyo-Sun;Boo, Yong-Chool
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.38 no.3
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    • pp.263-273
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    • 2012
  • Recent studies have uncovered attractive properties of para-coumaric acid (PCA) as a potential skin hywhitening agent. The purpose of the current study was to examine its UVB-shielding effects. Effects of PCA on the viability of HaCaT cells exposed to UVB were assessed in vitro in comparison with other aromatic amino acid metabolites that have similar UV absorption spectra. For in vivo test, PCA cream (1.5 %) and cream base were topically applied to the dorsal skin of SKH-1 hairless mice and the inflammatory responses due to UVB exposure were monitored by changes in skin color (erythema) and thickness (edema). The cream application-UVB exposure regimen was repeated every other day for a total of 12 sessions. When HaCaT cells were irradiated with UVB, there was a dose-dependent decline in cell viability. The cell viability decline due to UVB exposure (10 mJ $cm^{-2}$) was significantly prevented by 100 ${\mu}M$ PCA, cinnamic acid, urocanic acid, or indole acrylic acid by 39, 27, 39, or 31 %, respectively. Topical application of PCA cream onto the dorsal skin of hairless mice (10 ${\mu}g\;cm^{-2}$) attenuated the changes of color parameters, $L^*$, $a^*$, $b^*$ values, and thickness of the UVB (150 mJ $cm^{-2}$)-exposed skin by 59, 50, 58, and 53 %, respectively. The current study, together with the previous studies that demonstrated the antimelanogenic effects of PCA, suggested that PCA may prevent not only dyspigmentation but also inflammatory reactions in the UVB-exposed skin.

Study on the Chemical Management - 1. Chemical Characteristics and Occupational Exposure Limits under Occupational Safety and Health Act of Korea (화학물질 관리 연구-1. 산업안전보건법상 관리 화학물질의 특성과 노출기준 비교)

  • Park, Jihoon;Ham, Seunghon;Kim, Sunju;Lee, Kwonseob;Ha, Kwonchul;Park, Donguk;Yoon, Chungsik
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.25 no.1
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    • pp.45-57
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    • 2015
  • Objectives: This study aims to compare the physicochemical characteristics, toxicological data with Occupational Exposure Limits (OELs) of chemicals under the Occupational Safety and Health Act(OSHA) regulated by the Ministry of Employment and Labor of Korea. Methods: Information on chemicals which have OELs on physicochemical characteristics and toxicological data was collected using Material Safety Data Sheet(MSDS) from Korea Occupational Safety and Health Agency(KOSHA) and the Korea Information System for Chemical Safety Management(KISChem) in 2014. Statistical analyses including correlation and simple regression were performed to compare the OELs with chemical characteristics including molecular weight, boiling point, odor threshold, vapor pressure, vapor density, solubility and octanol-water partition coefficient(OWPC) and toxicological data such as median lethal dose($LD_{50}$) and median lethal concentration($LC_{50}$). Results: A total of 656 chemicals have OELs under OSHA in Korea. The numbers of chemicals which have eight-hour time weighted average(TWA) and short term exposure limits(STEL) are 618 and 190, respectively. TWA was significantly correlated with boiling point and STEL was only correlated with vapor pressure among physicochemical characteristics. Solubility and OWPC between "skin" and "no skin" substances which indicate skin penetration were not significantly different. Both $LD_{50}$ and $LC_{50}$ were correlated with TWA, while the $LC_{50}$ was not with STEL. As health indicators, health rating and Emergency Response Planning Guidelines(ERPG) rating as recommended by the National Fire Protection Association(NFPA) and American Industrial Hygiene Association(AIHA) were associated with OELs and reflect the chemical hazards. Conclusions: We found relationships between OEL and chemical information including physicochemical characteristics and toxicological data. The study has an important meaning for understanding present regulatory OELs.

Anti-Inflammatory Effect of Chondrus nipponicus Yendo Ethanol Extract on Lipopolysaccharide-Induced Inflammatory Responses in RAW 264.7 Cells (LPS로 유도된 RAW 264.7 세포에 대한 가락진두발 에탄올 추출물의 항염증 효과)

  • Kim, Min-Ji;Bae, Nan-Yong;Kim, Koth-Bong-Woo-Ri;Park, Ji-Hye;Park, Sun-Hee;Jang, Mi-Ran;Ahn, Dong-Hyun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.2
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    • pp.194-201
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    • 2016
  • The anti-inflammatory activity of ethanol extract from Chondrus nipponicus Yendo (CNYEE) was investigated by measuring production of a lipopolysaccharide-induced inflammatory response mediator. CNYEE had no cytotoxic effects on proliferation of macrophages compared to the control. CNYEE significantly inhibited (over 50%) NO production at $50{\mu}g/mL$, with inhibitory effects on expression levels of cytokines such as interleukin (IL)-6, tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), and IL-$1{\beta}$. In particular, IL-6 inhibitory activity of CNYEE was higher than 70% at $100{\mu}g/mL$. CNYEE also reduced protein expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and nuclear factor (NF)-${\kappa}B$ in a dose-dependent manner. CNYEE also significantly reduced phosphorylation of p38, extracellular signal-regulated kinase, and c-Jun N-terminal kinase. Therefore, these results suggest that CNYEE may have anti-inflammatory effects by modulating the NF-${\kappa}B$ and mitogen-activated protein kinases signaling pathways and may be used as an anti-inflammatory therapeutic material.

Regulation of Apoptosis and Cell Cycle in Irradiated Mouse Brain (마우스의 대뇌조직에서 방사선에 의한 아포토시스와 세포주기의 조절)

  • Oh, Won-Yong;Song, Mi-Hee;Chung, Eun-Ji;Seong, Jin-Sil;Suh, Chang-Ok
    • Radiation Oncology Journal
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    • v.19 no.2
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    • pp.146-152
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    • 2001
  • Purpose : To investigate the regulation of apoptosis and cell cycle in mouse brain irradiation. Materials and Methods : 8-week old male mice, C57B1/6J were given whole body $\gamma-radiation$ with a single dose of 25 Gy using Cobalt 60 irradiator. At different times 1, 2, 4, 8 and 24hr after irradiation, mice were killed and brain tissues were collected. Apoptotic cells were scored by TUNEL assay. Expression of p53, Bcl-2, and Bax and cell cycle regulating molecules; cyclins Bl, Dl, E and cdk2, cdk4, $p34^{cdc2}$ were analysed by Western blotting. Cell cycle was analysed by Flow cytometry. Results : The peak of radiation induced apoptosis is shown at 8 hour after radiation. With a single 25 Gy irradiation, the peak of apoptotic index in C57B1/6J is $24.0{\pm}0.25$ (p<0.05) at 8 hour after radiation. Radiation upregulated the expression of p53/tubulin, Bax/tubulin, and Bcl-2/tubulin with 1.3, 1.1 and 1.45 fold increase, respectively were shown at the peak level at 8 hour after radiation. The levels of cell cycle regulating molecules after radiation are not changed significantly except cyclin D1 with 1.3 fold increase. Fractions of Go-Gl, G2-M and S phase in the cell cycle does not specific changes by time. Conclusion : In mouse brain tissue, radiation induced apoptosis is particularly shown in a specific area, subependyma. These results and lack of radiation induced changes in cell cycle ofter better understanding of radiation response of noraml brain tissue.

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Clinical Efficacy and Hormonal Change of GnRH Antagonist in Controlled Ovarian Stimulation for IVF-ET (체외수정시술을 위한 과배란유도에 있어 GnRH Antagonist의 임상적 효용성과 혈중 호르몬 농도의 변화)

  • Moon, Shin-Yong;Chun, Eun-Kyung;Kim, Sang-Don;Choi, Young-Sik;Jee, Byung-Chul;Ku, Seung-Yup;Suh, Chang-Suk;Choi, Young-Min;Kim, Jung-Gu;Kim, Seok-Hyun
    • Clinical and Experimental Reproductive Medicine
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    • v.31 no.4
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    • pp.225-234
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    • 2004
  • Objectives: To evaluate the efficacy of GnRH antagonist cetrorelix in women undergoing controlled ovarian hyperstimulation (COH) for in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) and to determine changes in serum hormone concentrations during cetrorelix administration. Methods: We performed a clinical trial on 30 patients undergoing COH with highly purified follicular stimulating hormone (HP-FSH) and gonadotropin releasing hormone antagonist (GnRHant), cetrorelix. FSH was administrated from day 2 or 3 of cycle with fixed dose and adjusted according to individual response. 0.25 mg of cetrorelix was injected daily subcutaneously from stimulation day 5 until the day of hCG administration. Daily ultrasound monitoring was performed for growing follicles and serum levels of luteinizing hormone (LH), estradiol ($E_2$) and progesterone were measured daily during cetrorelix administration. Up to 4 embryos were transferred. Results: Mean age of enrolled patients was $32.0{\pm}3.4$ years (mean $\pm$ S.D.). All of 30 patients underwent oocyte pick-up, and embryo transfer was done in 28 patients. The total and mean numbers of received oocytes were 196 and $6.5{\pm}4.7$, the number of fertilized eggs was 111, and the fertilization rate was 56.6%. Total duration of FSH administration was $9.2{\pm}2.2$ days and mean of $24.3{\pm}7.7$ ampules of HP-FSH was administered. Total duration of cetrorelix administration was $5.7{\pm}1.9$ days. Serum LH and progesterone levels were maintained in the range of $1.4{\sim}2.9\;mIU/mL$ and $0.3{\sim}0.6\;ng/mL$, which respectively reflected effective prevention of premature LH surge. Clinical pregnancies were achieved in 9 patients, and overall clinical pregnancy rate was 30.0% per oocyte retrieval, and 32.1% per embryo transfer. Conclusion: GnRH antagonist is safe and convenient for COH for IVF-ET and effective with optimal pregnancy rate.

The Efficacy of Saururus chinensis on Cervical Cancer Cells : The Inhibitory Effect on the Function of E6 and E7 Oncogenes of HPV Type 16 (삼백초 추출물의 자궁경부암세포 억제 효능)

  • Chung, Yeon-Gu;Lee, Hae-Sook;Lee, Kyung-Ae;Joung, Ok;Oh, Won-Keun;Kim, Kwang-Dong;Lim, Jong-Seok;Moon, Ja-Young;Cho, Yong-Kweon;Park, Sue-Nie;Yoon, Do-Young
    • YAKHAK HOEJI
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    • v.46 no.6
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    • pp.426-432
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    • 2002
  • Cervical cancer is one of the leading causes of female death from cancer worldwide with about 500,000 deaths per year. A strong association between certain human papilloma viruses (HPV type 16 and 18) and cervical cancer has been well known. An extract of Saururus chinensis, named as PE-46, has been used to investigate whether this agent has the ability of inhibiting the oncogenes E6 and E7 of HPV type 16. PE-46 inhibited the proliferation of human cervical cancer cell lines in a dose response manner. PE-46 also inhibited the in vitro binding of E6 and E6AP which are essential for the binding and degradation of the tumor suppressor p53. In addition, PE-46 inhibited the in vitro binding of E7 and Rb which is essential tumor suppressor for the control of cell cycle. The levels of mRNA for E6 and E7 were also decreased by PE-46. SiHa cells treated with PE-46 induced G0/G1 arrest, resulting in inhibition of growth. Our study showed that the PE-46 can inhibit the cervical carcinomas via both inhibition of bindings between oncogenes and tumor suppressors, and inhibition of G1longrightarrowS transition. PE-46 inhibited the oncogenecity of E6 and E7 of HPV 16 type, thus could be used as a putative modulating agent for the treatment of cervical carcinomas caused by HPV.

External Radiation Therapy Combined with Hyperthermia in the Carcinoma of Extrahepatic Biliary System (간외 담관계암의 방사선치료와 온열치료의 병용요법)

  • Bae, Hoon-Sik
    • Radiation Oncology Journal
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    • v.10 no.1
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    • pp.49-58
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    • 1992
  • From January 1985 to September 1990, 7 patients with carcinoma of the extrahepatic biliary system received external radiaiton therapy combined with hyperthermia. Of the 3 patients with extrahepatic bile duct cancer, two were primary cholangiocarcinoma and one was metastatic peripancreatic carcinoma. Of the 4 patients with carcinoma of the gallbladder, two were locor-egionally advanced and unresectable carcinoma and the remaining two were local-regional recurrence after cholecystectomy. They were all pathologicallly proven adenocarcinoma. The radiation dose received ranged from 3000 cGy/2weeks to 5040 cGy/7 weeks. The hyperthermia was done once or twice a week and 4 to 12 sessions in total. The tumor response was confirmed by T-tube cholangiography, percutaneous transhepatic cholangiography and CT scan. 6 out of 7 ($86\%$) showed partial regression of the tumor. The median survival time was 7 months (range $4\~11$ months).6 out of 7 patients were dead: one died of septicemia, 4 of primary disease, one of distant metastases. Only one out of 7 patients is still alive but new metastatic lesion was found. There was not any treatment related deaths. There was also no evidence of treatment related problems with liver, stomach and duodenum, although the observation period was short.

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Role of Nuclear Factor (NF)-κB Activation in Tumor Growth and Metastasis (종양의 성장 및 전이에 있어서 NF-κB의 역할)

  • Ko, Hyun-Mi;Choi, Jung-Hwa;Ra, Myung-Suk;Im, Suhn-Young
    • IMMUNE NETWORK
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    • v.3 no.1
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    • pp.38-46
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    • 2003
  • Background: Platelet-activating factor (PAF) induces nuclear factor $(NF)-{\kappa}B$ activation and angiogenesis and increases tumor growth and pulmonary tumor metastasis in vivo. The role of $NF-{\kappa}B$ activation in PAF-induced angiogenesis in a mouse model of Matrigel implantation, and in PAF-mediated pulmonary tumor metastasis were investigated. Methods: Angiogenesis using Matrigel and experimental pulmonary tumor metastasis were tested in a mouse model. Electrophoretic mobility shift assay was done for the assessment of $NF-{\kappa}B$ translocation to the nucleus. Expression of angiogenic factors, such as tumor necrosis factor $(TNF)-{\alpha}$, interleukin $(IL)-1{\alpha}$, basic fibroblast growth factor (bFGF), and vascular endothelial growth factor (VEGF) were tested by RT-PCR and ELISA. Results: PAF induced a dose- and time-dependent angiogenic response. PAF-induced angiogenesis was significantly blocked by PAF antagonist, CV6209, and inhibitors of $NF-{\kappa}B$ expression or action, including antisense oligonucleotides to p65 subunit of $NF-{\kappa}B$ (p65 AS) and antioxidants such as ${\alpha}$-tocopherol and N-acetyl-L-cysteine. In vitro, PAF activated the transcription factor, $NF-{\kappa}B$ and induced mRNA expression of $TNF-{\alpha}$, $IL-1{\alpha}$, bFGF, VEGF, and its receptor, KDR. The PAF-induced expression of the above mentioned factors was inhibited by p65 AS or antioxidants. Also, protein synthesis of VEGF was increased by PAF and inhibited by p65 AS or antioxidants. The angiogenic effect of PAF was blocked when anti-VEGF antibodies was treated or antibodies against $TNF-{\alpha}$, $IL-1{\alpha}$, and bFGF was co-administrated, but not by antibodies against $TNF-{\alpha}$, $IL-1{\alpha}$, and bFGF each alone. PAF-augmented pulmonary tumor metastasis was inhibited by p65 AS or antioxidants. Conclusion: These data indicate that PAF increases angiogenesis and pulmonary tumor metastasis through $NF-{\kappa}B$ activation and expression of $NF-{\kappa}B$-dependent angiogenic factors.

Quantitative Microbial Risk Assessment for Clostridium perfringens in Natural and Processed Cheeses

  • Lee, Heeyoung;Lee, Soomin;Kim, Sejeong;Lee, Jeeyeon;Ha, Jimyeong;Yoon, Yohan
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.8
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    • pp.1188-1196
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    • 2016
  • This study evaluated the risk of Clostridium perfringens (C. perfringens) foodborne illness from natural and processed cheeses. Microbial risk assessment in this study was conducted according to four steps: hazard identification, hazard characterization, exposure assessment, and risk characterization. The hazard identification of C. perfringens on cheese was identified through literature, and dose response models were utilized for hazard characterization of the pathogen. For exposure assessment, the prevalence of C. perfringens, storage temperatures, storage time, and annual amounts of cheese consumption were surveyed. Eventually, a simulation model was developed using the collected data and the simulation result was used to estimate the probability of C. perfringens foodborne illness by cheese consumption with @RISK. C. perfringens was determined to be low risk on cheese based on hazard identification, and the exponential model ($r=1.82{\times}10^{-11}$) was deemed appropriate for hazard characterization. Annual amounts of natural and processed cheese consumption were $12.40{\pm}19.43g$ and $19.46{\pm}14.39g$, respectively. Since the contamination levels of C. perfringens on natural (0.30 Log CFU/g) and processed cheeses (0.45 Log CFU/g) were below the detection limit, the initial contamination levels of natural and processed cheeses were estimated by beta distribution (${\alpha}1=1$, ${\alpha}2=91$; ${\alpha}1=1$, ${\alpha}2=309$)${\times}$uniform distribution (a = 0, b = 2; a = 0, b = 2.8) to be -2.35 and -2.73 Log CFU/g, respectively. Moreover, no growth of C. perfringens was observed for exposure assessment to simulated conditions of distribution and storage. These data were used for risk characterization by a simulation model, and the mean values of the probability of C. perfringens foodborne illness by cheese consumption per person per day for natural and processed cheeses were $9.57{\times}10^{-14}$ and $3.58{\times}10^{-14}$, respectively. These results indicate that probability of C. perfringens foodborne illness by consumption cheese is low, and it can be used to establish microbial criteria for C. perfringens on natural and processed cheeses.

Effects of Different UV-B Levels on Growth, Antioxidant Contents and Activities of Related Enzymes in Cucumber(Cucumis sativus L.). (UV-B 강도 변화가 오이의 생장 및 항산화 물질 함량과 관련 효소의 활성에 미치는 영향)

  • Kim, Hak-Yoon;Shin, Dong-Hyun;Kim, Kil-Ung
    • Korean Journal of Environmental Agriculture
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    • v.19 no.4
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    • pp.309-313
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    • 2000
  • To investigate the effects of different UV-B levels on growth and biochemical defense response in plants, cucumber plants were subjected to three levels of biologically effective ultraviolet-B $(UV-B_{BE})$ radiation [daily dose: 0.03 (No), 6.40 (Low) and $11.30\;(High)\;kJ{\cdot}m^{-2}$, $UV-B_{BE}$] in the growth chambers for 3 weeks during the early growth period. Enhanced UV-B radiation drastically decreased both dry weight and leaf area of cucumber. With increasing UV-B intensity, chlorophyll content was decreased, however the level of malondialdehyde was highly increased linearly. Total contents of ascorbic acid and glutathione were tended to increase by UV-B, while the ratios of dehydroascorbate/ascorbate and oxidized glutathione/reduced glutathione were significantly increased with increasing UV-B intensity in cucumber. All the enzyme activities investigated (superoxide dismutase, ascorbate peroxidase, dehydroascorbate reductase, guaiacol peroxidase etc.) in cucumber were increased by the UV-B enhancement. These results suggested that enhanced UV-B irradiation caused photooxidative stress in cucumber plant and resulted in significant reduction in plant growth. Biochemical protection responses might be activated to prevent the leaves from damaging effects of oxidative stress generated by UV-B irradiation.

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