• Title/Summary/Keyword: Dose-response

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Apoptotic response to various apoptotic inducers on cultured HCE cells (여러 가지 apoptosis 유도 물질의 각막 상피세포에 대한 apoptosis 유도 반응)

  • Kim, Jai-Min;Kim, Soon-Ae;Yoo, Geun-Chang;Seo, Eun-Sun
    • Journal of Korean Ophthalmic Optics Society
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    • v.8 no.1
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    • pp.65-71
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    • 2003
  • The corneal epithelium is constantly being shed. The mechanism of corneal desquamation is not fully understood. Apoptosis, programmed cell death, may play a role. Apoptosis can be induced by a number of factors and different mechanisms. The study was performed to examine the apoptotic index induced in human corneal epithelial cells maintained in tissue culture by various apoptotic inducers. Various inducers, recombinant human cytokines($INF{\gamma}$, $TNF{\alpha}$, FASAb), actinomycin D. camptothecin, cycloheximide, dexamethasone and etoposide, were purchased from commercial suppliers. Inducers at manufacturer-recommended concentration were added to the corneal epithelial cells for 48 hours. Cell viability was measured using MTT assay. The cells were then assessed for the level of apoptosis. Morphologic changes and quantification of apoptotic cells were determined and counted under fluorescence microscope after inducers-treated human corneal epithelial (HCE) cells for 48 hours with Hoechst 33342 staining. Annexin V-FITC/PI staining and DePsipher assay. The expression of Fas protein was studied by immunocytochemistry. All inducers induced apoptosis in HCE cells in a dose dependent manner. Actinomycin D. camptothecin and etoposide induced apoptosis at lower than manufacturer-recommended concentration, while cytokines, cycloheximide and dexamethasone induced apoptosis at higher concentrations at the end of 48 hours. All inducers elicited typical apoptotic morphologic changes (chromatin condensation, nucleus fragmentations non-orange-red colored mitochondria) and expresses Fas protein highly. Apoptotic index of HCE cells by these inducers was different from the other cell lines. RNA synthesis inhibitor and topoisomerase inhibitors induced apoptosis at lower concentration than manufacturer-recommended concentration. Cytokines, cycloheximide and dexamethasone were able to produce apoptosis at 10 times higher concentrations. RNA synthesis inhibitor and topoisomerase inhibitors are more sensitive than intracellular receptor-activators in apoptotic induction of HCE cells.

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Biological Activity of Bamboo Salt

  • Shin, Hye-Young;Na, Ho-Jeong;Moon, Phil-Dong;Seo, Sang-Wan;Shin, Tae-Yong;Hong, Seoung-Heon;Lee, Ki-Nam;Park, Rae-Kil;Kim, Hyung-Min
    • Food Industry And Nutrition
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    • v.9 no.1
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    • pp.36-45
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    • 2004
  • Bamboo salt has been used for the purpose of prevention and treatment of various diseases in Korea. Present study was carried out to ascertain the effects of purple bamboo salt upon anti-allergic effect, anti-inflammatory activity and immune-enhance effect as well. Purple bamboo salt significantly inhibited the ear swelling response and histamine release induced by compound 48/80 in mice and rat peritoneal mast cells. Purple bamboo salt (0.01 ∼ lg/kg) also dose-dependently inhibited the passive cutaneous anaphylaxis by oral administration. Purple bamboo salt (1 mg/mL) in hibited phorbol 12-myristate 13-acetate plus calcium ionophore A23187-stimulated tumor necrosis factor (TNF)-${\alpha}$, interleukin (IL)-1${\beta}$ and IL-6 secretion, by 67.04${\pm}$0.08%, 68.01${\pm}$1.85%, 69.48${\pm}$0.54%, respectively. In addition, purple bamboo salt inhibited the expression of TNF-${\alpha}$ mRNA in HMC-1 cells. Finally, we investigated the effect of purple bamboo salt in the forced swimming test (FST) and the change of purple bamboo salt-mediated cytokine production from MOLT-4 cells. At the 7th, immobility time was significantly decreased in the purple bamboo salt-administration group (35.4 ${\pm}$5.9 s for 1 g/kg) in comparison with the control group (93.2 ${\pm}$ 15.45). After FST, the content of glucose in the blood serum was increased and the levels of blood urea nitrogen, lactic dehydrogenase was decreased in purple bamboo salt-administration group. However, it had no effect on the elevation of CK and TP level. Purple bamboo salt (1 mg/mL) significantly increased the interferon (IFN)-${\gamma}$ and IL-2 level compared with media control (about 3.7-fold for IFN-${\gamma}$, about 3.5-fold for IL-2, p〈0.05) but did not affect the IL-4.

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Changes in Plasma Levels of Inhibin and Follicle Stimulating Hormone in Buffaloes Superovulated with eCG

  • Singh, Baljit;Dixit, V.D.;Dixit, V.P.;Singh, P.;Georgie, G.C.;Lohan, I.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.9
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    • pp.1205-1209
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    • 2000
  • The present study was undertaken to investigate the effect of stimulation of follicular development with eCG on the peripheral levels of inhibin and FSH in Murrah buffaloes. Estrus was synchronized in five normally cycling females by insertion of Crestar (Intervet, Boxmeer, Holland) implants for nine days. Estradiol valerate was administered i.m. on the day of implant insertion. On the 10th day of the induced estrous cycle a single dose of 3000 IU eCG (Folligon, Intervet, Boxmeer, Holland) was given, followed by treatment with 25 mg of $PGF_2$ alpha (Lutalyse, Upjohn, Belgium) 48 h later. Blood samples were obtained during the induced estrus, on cycle day 10 (luteal phase), at the superovulatory estrus (43 h after PGF) and during the periovulatory period (64 h after PGF). Ultrasonography was done daily to monitor follicular development. Plasma concentrations of inhibin and FSH were determined by specific radioimmunoassays. Differences between $mean{\pm}SEM$ values of different phases of the cycle were compared by ANOVA. The mean number of small (2-5 mm), medium (6-9 mm) and large (>10 mm) follicles observed two days after eCG treatment and on the day of superovulatory estrus was $2.8{\pm}0.31$, $5.2{\pm}0.30$ and $1.4{\pm}0.09$ and $1.9{\pm}0.21$, $2.8{\pm}0.40$ and $5.0{\pm}0.83$, respectively. The mean number of ovulations was $3.6{\pm}0.37$ and the mean number of unovulated follicles was $6.1{\pm}0.47$. Most of the follicles >10 mm in diameter had ovulated (72%). The mean ${\pm}SEM $ of plasma inhibin concentration $(2584.15{\pm}17.92pg/ml)$ during the superovulatory estrus was significantly higher $(p{\leq}0.05)$ than during the induced estrus $(749.87{\pm}17.29pg/ml)$, the luteal phase $(1099.54{\pm}24.98pg/ml)$ and periovulatory period $(1682.71{\pm}29.88pg/ml)$, respectively. $Mean{\pm}SEM$ plasma FSH concentration during the induced estrus $(10.35{\pm}0.41ng/ml)$ was not different from that during the superovulatory estrus $(8.52{\pm}0.39ng/ml)$, but was significantly higher $(p{\leq}0.05)$ than during the luteal phase $(2.81{\pm}0.42ng/ml)$ and periovulatory period $(5.7{\pm}0.28ng/ml)$. These data indicate that treatment with eCG in buffaloes for inducing superovulation results in a significant elevation in plasma inhibin levels and a decrease in plasma FSH levels during the superovulatory estrus. Thus, we suggest that the elevated plasma inhibin coming from fully developed follicles continued for a long time which results in inhibition of FSH leading to poor ovulation in the remaining follicles, which may be the cause of suboptimal superovulatory response.

Association between Cigarette Smoking History and Mortality in 36,446 Health Examinees in Korea

  • Kim, Kyoungwoo;Yoo, Taiwoo;Kim, Yeonju;Choi, Ji-Ho;Myung, Seung-Kwon;Park, Sang-Min;Hong, Yun-Chul;Cho, Belong;Park, Sue K.;Yoo, Keun-Young
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.14
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    • pp.5685-5689
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    • 2014
  • Background: It is well known that smoking is a preventable factor for all-cause mortality; however, it is still questionable how many years after smoking cessation that people will have reduced risk for mortality, in particular in those with a high interest in their own health. We aimed to examine the association between time since quitting smoking and total mortality among past-smokers relative to current smokers. Materials and Methods: We enrolled 36,446 health examinees that voluntarily taken with diverse health check-up packages of high cost burden in 1995-2003 and followed them till death by 2004. The history of cigarette smoking consumption was collected using a self-administrative questionnaire at the first visit time. Mortality risk by smoking cessation years was analyzed using Cox's proportional hazard model. Results: Compared to non-smokers, male smokers over 15 pack-years had higher risk for total mortality (HR=1.60, 95%CI 1.23-2.14). The mortality risk in female smokers with same pack-years was more pronounced than that in male smokers (HR=2.83, 95%CI 1.17-7.04) despite a small number of cases. Compared to current smokers, a decrease of total mortality was observed among those who ceased smoking, and inverse dose-response was found with years after cessation: RR 0.98 (95%CI, 0.64-1.41) (<2 yrs), 0.60 (95%CI, 0.43-0.83) (3-9 yrs), and 0.58 (95%CI, 0.43-0.79) (${\geq}10$ yrs). Conclusions: A reduced risk of total mortality was observed after 3 years of smoking cessation. Our findings suggest that at least 3 years of smoking cessation may contribute to reduce premature mortality among Asian men.

Mechanism underlying Chios gum mastic-induced apoptosis on SCC25 human tongue squamous cell carcinoma cell line

  • Lee, Seung-Eun;Hur, Young-Joo;Kim, In-Ryoung;Kwak, Hyun-Ho;Kim, Gyoo-Cheon;Shin, Sang-Hun;Kim, Chul-Hoon;Park, Bong-Soo
    • International Journal of Oral Biology
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    • v.34 no.2
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    • pp.61-72
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    • 2009
  • Chios gum mastic (CGM) is a resin produced from the stem and leaves of Pistiacia lentiscus L var chia, a plant which grows only on Chios Island in Greece. CGM has been used for many centuries as a dietary supplement and folk medicine for stomach and duodenal ulcers in many Mediterranean countries and is known also to induce cell cycle arrest and apoptosis in some cancer cells. In this study, we further investigated the induction and mechanisms underlying the apoptotic response to CGM treatment in the SCC25 human tongue squamous cell carcinoma cell line. The viability of SCC25 cells, human normal keratinocytes (HaCaT cells) and human gingival fibroblasts (HGF-1 cells), and the growth inhibition of SCC25 cells were assessed by MTT assay and clonogenic assay, respectively. Staining with Hoechst and hemacolor dyes and TUNEL assays were employed to detect SCC25 cells undergoing apoptosis. SCC25 cells were treated with CGM, and this was followed by western blotting, immunocytochemistry, confocal microscopy, FACScan flow cytometry, MMP activity and proteasome activity analyses. CGM treatment of SCC25 cells was found to result in a time- and dosedependent decrease in cell viability, a dose-dependent inhibition of cell growth, and apoptotic cell death. Interestingly, CGM showed a remarkable level of cytotoxicity in SCC25 cells but not in normal cells. Tested SCC25 cells also showed several lines of apoptotic manifestation. Taken together, our present findings demonstrate that CGM strongly inhibits cell proliferation by modulating the expression of G1 cell cycle-related proteins and induces apoptosis via the proteasome, mitochondria and caspase cascades in SCC25 cells.

Anti-tumor Activity of Fermented Liquid Opuntia humifusa in Cervical Cancer Cells and Its Chemical Composition (손바닥 선인장(Opuntia humifusa) 발효액의 화학적 성분과 자궁경부암 세포주에 대한 항암작용)

  • Choi, Hwa-Jung;Park, Seung-Chun;Hong, Tae-Hee
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.10
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    • pp.1525-1530
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    • 2005
  • The purpose of this study is to investigate anti-tumor activities, general composition, elemental composition and mineral contents of fermented liquid stem, root and fruit of Opuntia humifusa. In the general composition, the energy, crude protein, crude lipid and crude carbohydrate contents of fermented liquid stem were 86.21 Kcal, 0.92$\%$, 0.12$\%$, and 20.34$\%$, respectively. Fermented liquid fruit showed 65.32 Kcal, 1.04$\%$, 0.08$\%$, and 15.15$\%$. In mineral analysis, fermented liquid stem and fruit showed 1,800 and 388 mg of calcium per 100g. The ferrous concentrations of fermented liquid stem and fruit were 21 and 10 mg per 100 g, respectively. Methanol, ethanol and water extracts of nonfermented liquid stem and fruit did not inhibit the proliferation in human cervical cancer cells (Caski, SiHa and HaCaT), but the fermented liquid fruit showed the inhibition of Proliferation with dose-response manner in Caski and SiHa cells, but not HaCaT. Therefore, it suggests that fermented cactus may be used as one of potential adjuvant for the treatment of cervical carcinomas.

Cytoprotective Effect of Zinc-Mediated Antioxidant Gene Expression on Cortisol-Induced Cytotoxicity (Cortisol 유발 세포독성에 대한 아연 관련 항산화 유전자 발현 증가에 의한 세포보호 효과)

  • Chung, Mi Ja;Kim, Sung Hyun;Hwang, In Min
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.5
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    • pp.649-656
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    • 2015
  • The protective effect of zinc against cortisol-induced cell injury was examined in rainbow trout gill epithelial cells. Cells exposed to cortisol for 24 h showed increased leakage of lactate dehydrogenase (LDH) as well as decreased cell viability in a dose-dependent manner. Treatment with zinc ($100{\mu}M$ $ZnSO_4$) reduced the severity of both LDH release and cell death as well as protected cells against cortisol-induced caspase-3 activation, indicating reduction of apoptosis. Cortisol-induced cell death, leakage of LDH, and caspase-3 activation were blocked by the glucocorticoid receptor antagonist Mifepristone (RU-486), suggesting that cell injury was cortisol-dependent. In addition, we studied the effect of zinc on the expression of antioxidant genes such as metallothionein A (MTA), metallothionein B (MTB), glutathione-S-transferase (GST), and glucose-6-phosphate dehydrogenase (G6PD) during cortisol-induced cell injury. MTA, MTB, GST, and G6PD mRNA levels increased after treatment with zinc or cortisol, separately or in combination. Higher mRNA levels of MTA, MTB, GST, and G6PD were detected when cells were treated with $100{\mu}M$ $ZnSO_4$ and $1{\mu}M$ cortisol in combination at the same time compared to treatment with zinc or cortisol separately. Cells treated with zinc showed increased intracellular free zinc concentrations, and this response was significantly enhanced in cells treated with cortisol and zinc. In conclusion, zinc treatment inhibited cortisol-induced cytotoxicity and apoptosis through indirect antioxidant action.

c-Jun N-terminal Kinase Contributes to Norepinephrine-Induced Contraction Through Phosphorylation of Caldesmon in Rat Aortic Smooth Muscle

  • Lee, Youn-Ri;Lee, Chang-Kwon;Park, Hyo-Jun;Kim, Hyo-Jin;Kim, Jung-Hwan;Kim, Jae-Heung;Lee, Keun-Sang;Lee, Yun-Lyul;Min, Kyung-Ok;Kim, Bo-Kyung
    • Journal of Korean Physical Therapy Science
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    • v.13 no.2
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    • pp.129-135
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    • 2006
  • Vascular smooth muscle contraction is mediated by activation of extracellular signal-regulated kinase (ERK) 1/2, an isoform of mitogen-activated protein kinase (MAPK). However, the role of stress-activated protein kinase/c-Jun N-terminal kinase (JNK) in vascular smooth muscle contraction has not been defined. We investigated the role of JNK in the contractile response to norepinephrine (NE) in rat aortic smooth muscle. NE evoked contraction in a dose-dependent manner, and this effect was inhibited by the JNK inhibitor SP600125. NE increased the phosphorylation of JNK, which was greater in aortic smooth muscle from hypertensive rats than from normotensive rats. NE-induced JNK phosphorylation was significantly inhibited by SP600125 and the conventional-type PKC (cPKC) inhibitor Go6976, but not by the Rho kinase inhibitor Y27632 or the phosphatidylinositol 3-kinase inhibitor LY294002. Thymeleatoxin, a selective activator of cPKC, increased JNK phosphorylation, which was inhibited by $G{\ddot{o}}6976$. SP600125 attenuated the phosphorylation of caldesmon, an actin-binding protein whose phosphorylation is increased by NE. These results show that JNK contributes to NE-mediated contraction through phosphorylation of caldesmon in rat aortic smooth muscle, and that this effect is regulated by the PKC pathway, especially cPKC.

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Study on Health Risk Assessment of Carcinogenic Chemicals in Drinking Water (음용수 중 유해 화학 물질에 대한 위해성 평가에 관한 연구 - I. 발암성 화학 물질을 중심으로 -)

  • Chung, Yong;Shin, Dong-Chun;Kim, Jong-Man;Park, Seong-Eun;Yang, Ji-Yeon;Lee, Ja-Koung;Hwang, Man-Sik;Park, Yeon-Shin
    • Environmental Analysis Health and Toxicology
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    • v.10 no.1_2
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    • pp.1-14
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    • 1995
  • The purpose of this research is to assess the health risk of pollutants in drinking water and recommend the guidelines and management plans for maintaining good quality of drinking water. This study has been funded as a national project for three years from 1992 to 1995. This study(the second year, 1993-1994) was conducted to monitor 32 species of carcinogenic chemicals such as volatile organic compounds(VOCs), polynuclear aromatic hydrocarbons(PAHs), pesticides and heavy metals of drinking water at some area in six cities of Korea, and evaluate health risk due to these chemicals through four main steps of risk assessment in drinking water. In hazard identification, 32 species of carcinogenic chemicals were identified by the US EPA classification system. In the step of exposure assessment, sampling of raw, treated and tap water from the public water supply system had been conducted from 1993 to 1994, and 32 chemicals were analyzed. In dose-response assessment, cancer potencies, unit risk estimates and virtually safe doses of carcinogens were obtained by TOX-RISK (Version 3.1). In risk characterization of detected chemicals, health risk due to carcinogens such as vinyl chloride, carbon tetrachloride, dichloromethane, 1, 2-dichloromethane, chloroform, benzene and arsenic of tap water in several cities exceeded 10$^{-5}$ level. We suggest that non-regulated chemicals which exceed 10$^{-5}$ excess cancer risk level, such as vinyl chloride, carbon tetrachloride and 1, 2-dichloroethane, should be monitored periodically and be regulated by the Drinking Water Management Act, and database for exposure parameter of our own situation should be established.

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Effects of Manganese Exposure on the Testis Function and Serum Prolactin Concentration in Rat (망간 노출이 흰쥐의 정소기능과 혈청 프로락틴 농도에 미치는 영향)

  • Lee, Chae-Kwan
    • Development and Reproduction
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    • v.13 no.4
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    • pp.321-327
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    • 2009
  • This study aimed to examine the testis toxicities of metal compound, manganese (Mn), which may be generated as mist or fume in the industrial sites. As well as serum prolactin (PRL) concentration was analyzed because Mn accumulation in basal ganglia up-regulates serum PRL and hyperprolactinemia consecutively induces the testis toxicity. Male F344 rats were divided into the 4 groups (2 controls and 2 Mn treated groups, n=10) on the basis of the test condition (inhalation, Mn $1.5mg/m^3$ or not) and treatment period (for 4-weeks and 13-weeks). The treatment time was 6 hr. a day, 5 days a week for the whole body. Basic tests including changes in body weight, feed rate were observed. Blood and testis Mn concentration, and testis toxicity test such as the number and deformity test of sperm were also observed. Serum PRL level was analyzed by ELISA to certify the relationship between the Mn induced increase of the serum PRL level and sperm production. Blood and testis Mn concentrations were significantly and dose-dependently increased. Sperm count was decreased in Mn-treatment groups than control in a treatment time dependent manner. Morphological analysis of cauda epidydimal sperm showed that the frequencies of morphologically abnormal sperms such as bent tail and small head were increased in the both Mn-treatment groups than control. A significant increase in serum PRL levels was found in response to Mn treatment but it was not hyperprolactinemia range. These results suggest that treatment of Mn up-regulates the serum PRL concentration and induces the testis toxicity. The No Aversed Effect Level (NOAEL) of inhaled Mn on the male rat testis may be under the $1.5mg/m^3$.

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