• Title/Summary/Keyword: EXPOSURE

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Suppressive effects of ethanol extract of Aralia elata on UVB-induced oxidative stress in human keratinocytes (자외선 B를 조사한 인간유래각질세포에서 두릅순 에탄올추출물의 산화적 스트레스 억제효과)

  • Kwak, Chung Shil;Yang, Jiwon
    • Journal of Nutrition and Health
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    • v.49 no.3
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    • pp.135-143
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    • 2016
  • Purpose: Ultraviolet (UV)-induced oxidative stress contributes to several adverse biological effects on skin. Many phenolic phytochemicals have been shown to have antioxidant properties and protect skin cells from UV-induced oxidative damage. In this study, we investigated whether or not Aralia elata (AE) has a protective effect against UVB-induced reactive oxygen species (ROS), ultimately leading to photoaging. Methods: Phenolic content of dried AE and antioxidant properties of AE extract in 70% ethanol weredetermined by measuring DPPH and ABTS radical scavenging activities and ferric reducing antioxidant power (FRAP). The effect of AE extract on cellular ROS generation and expression levels of oxidative stress-response proteins such as superoxide dismutase (SOD)-1, catalase, nuclear factor-erythroid 2-related factor (Nrf)-2, and heme oxygenase (HO)-1 in UVB-irradiated ($75mJ/cm^2$) human keratinocytes (HaCaT) were further determined by 2'-7'-dichlorofluoresceine diacetate assay and Western blotting, respectively. Results: The total phenolic and flavonoid contents of dried AE were 20.15 mg tannic acid/g and 18.75 mg rutin/g, respectively. The $IC_{50}$ of AE extract against DPPH radical was $98.5{\mu}g/mL$, and ABTS radical scavenging activity and FRAP upon treatment with $1,000{\mu}g/mL$ of AE extract were $41.8{\mu}g\;ascorbic\;acid\;(AA)\;eq./mL$ and $29.7{\mu}g\;AA\;eq./mL$,m respectively. Pretreatment with AE extract significantly reduced (p < 0.05) ROS generation compared to that in UVB-irradiated control HaCaT cells. Pretreatment with AE extract reversed reduction of Nrf-2 and SOD-1 protein expression and induction of HO-1 protein expression caused by UVB exposure in HaCaT cells, whereas it did not affect catalase expression. Conclusion: AE extract in 70% ethanol demonstrated a protective effect against UVB-induced oxidative stress and decreased expression of Nrf-2 and SOD-1 in human keratinocytes. These findings suggest that AE ethanol extract might have potential as a natural resource for a skin anti-photoaging product in the food and cosmetic industry.

Effects of Nutrient Strength and Light Intensity on Nutrient Uptake and Growth of Young Kalanchoe Plants (Kalanchoe blossfeldiana 'Marlene') at Seedling Stage (배양액의 농도와 광강도가 단일처리전 칼랑코에 유묘의 양분흡수와 생육에 미치는 영향)

  • Lu, Yin-Ji;Son, Jung-Eek
    • Journal of Bio-Environment Control
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    • v.14 no.3
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    • pp.149-154
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    • 2005
  • It is very important to make shorter and healthier pot plants with increased numbers of branch at a growing stage before short-day exposure. Especially light and nutrient conditions directly affect the growth and quality of the plants as described above. In this study, the effects of nutrient strength and light intensity on the nutrient uptake and growth of young Kalanchoe plants (Kalanchoe blossfeldiana 'Marlene') during this growth stage were investigated. The plants were grown under two radiation integral (15.8 and 7.9 $mol{\cdot}m^{-2}{\cdot}d^{-1}$, PPF) and three EC (0.8, 1.6 and 2.4 $dS{\cdot}m^{-1}$) conditions. Leaf area, fresh weight, dry weight and number of branch were higher at a higher PPF, and this tendency was more evident at an EC above 1.6$dS{\cdot}m^{-1}$. The plants became higher at a lower PPF. When the EC was at 0.8 $dS{\cdot}m^{-1}$, the plants did not grow so healthy regardless of PPF conditions. EC decrement in the nutrient solution was increased with increase of nutrient strength. With growth stage, the nutrient uptake was increased with increases of nutrient strength and PPF. At a higher PPF, $NO_3-N,\;K^{+}\;and\;Ca^{2+}$ were much more absorbed, and especially the uptake of $K^{+}$ was 1.1 to 1.5 times greater than that or $NO_3-N$. From the results, the EC needed above 1.6 $dS{\cdot}m^{-1}$ during the seedling stage in order to make more healthy Kalanchoe plants having more leaf area, fresh weight, dry weight and number of branches under adequate light conditions.

Radiation Dose during Transmission Measurement in Whole Body PET/CT Scan (전신 PET/CT 영상 획득 시 투과 스캔에서의 방사선 선량)

  • Son Hye-Kyung;Lee Sang-Hoon;Nam So-Ra;Kim Hee-Joung
    • Progress in Medical Physics
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    • v.17 no.2
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    • pp.89-95
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    • 2006
  • The purpose of this study was to evaluate the radiation doses during CT transmission scan by changing tube voltage and tube current, and to estimate the radiation dose during our clinical whole body $^{137}Cs$ transmission scan and high quality CT scan. Radiation doses were evaluated for Philips GEMINI 16 slices PET/CT system. Radiation dose was measured with standard CTDI head and body phantoms in a variety of CT tube voltage and tube current. A pencil ionization chamber with an active length of 100 mm and electrometer were used for radiation dose measurement. The measurement is carried out at the free-in-air, at the center, and at the periphery. The averaged absorbed dose was calculated by the weighted CTDI ($CTDI_w=1/3CTDI_{100,c}+2/3CTDI_{100,p}$) and then equivalent dose were calculated with $CTDI_w$. Specific organ dose was measured with our clinical whole body $^{137}Cs$ transmission scan and high quality CT scan using Alderson phantom and TLDs. The TLDs used for measurements were selected for an accuracy of ${\pm}5%$ and calibrated in 10 MeV X-ray radiation field. The organ or tissue was selected by the recommendations of ICRP 60. The radiation dose during CT scan is affected by the tube voltage and the tube current. The effective dose for $^{137}Cs$ transmission scan and high qualify CT scan are 0.14 mSv and 29.49 mSv, respectively. Radiation dose during transmission scan in the PET/CT system can measure using CTDI phantom with ionization chamber and anthropomorphic phantom with TLDs. further study need to be peformed to find optimal PET/CT acquisition protocols for reducing the patient exposure with same image qualify.

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Evaluation of Absorbed Dose and Skin Dose with MDCT Using Ionization Chamber and TLD (이온 전리함 및 TLD 법을 이용한 Multi-Detector Computed Tomography의 흡수선량 및 체표면 선량 평가)

  • Jeon, Kyung Soo;Oh, Young Kee;Baek, Jong Geun;Kim, Ok Bae;Kim, Jin Hee;Choi, Tae Jin;Jeong, Dong Hyeok;Kim, Jeong Kee
    • Progress in Medical Physics
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    • v.24 no.1
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    • pp.35-40
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    • 2013
  • Recently, the uses of Multi-Detector Computed Tomography (MDCT) for radiation treatment simulation and planning which is used for intensity modulated radiation therapy with high technique are increasing. Because of the increasing uses of MDCT, additional doses are also increasing. The objective of this study is to evaluate the absorbed dose of body and skin undergoing in MDCT scans. In this study, the exposed dose at the surface and the center of the cylindrical water phantom was measured using an pencil ionization chamber, 30 cc ionization chamber and TL Powder. The results of MDCT were 31.84 mGy, 33.58 mGy and 32.73 mGy respectively. The absorbed dose at the surface showed that the TL reading value was 33.92 mGy from MDCT. These results showed that the surface dose was about 3.5% from the MDCT exposure higher than a dose which is located at the center of the phantom. These results mean that the total exposed dose undergoing MDCT 4 times (diagnostic, radiation therapy planning, follow-up et al.), is about 14 cGy, and have to be considered significantly to reduce the exposed dose from CT scan.

IL-1 AND TNF-α RELEASE IN HUMAN POLYMORPHONUCLEAR LEUKOCYTES AFTER EXPOSURE TO CALCIUM HYDROXIDE TREATED Porphyromonas endodontalis LIPOPOLYSACCHARIDE (수산화칼슘 처리된 Porphyromonas endodontalis Lipopolysaccharide가 다형핵백혈구의 IL-1과 TNF-α 생성에 미치는 영향에 관한 연구)

  • Park, Chan-Je;Park, Dong-Sung;Yoo, Hyeon-Mee;Oh, Tae-Seok;Lim, Sung-Sam
    • Restorative Dentistry and Endodontics
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    • v.27 no.5
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    • pp.463-472
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    • 2002
  • Bacterial lipopolysaccharide (LPS) plays a major role in stimulating the synthesis and release of the principal osteoclast-activating cytokines, namely, interleukin 1 and tumor necrosis factor-$\alpha$ from immune cells. Although rnonocytes/macrophages are the main producers of these cytokines, recent evidence has indicated that polymorphonuclear leukocytes (PMN) have the ability to release IL-1 and TNF-$\alpha$. Calcium hydroxide has been shown to be an effective medicament in root canal infections, reducing the microbial titre within the canal. It has been proposed that the therapeutic effect of Ca(OH)$_2$ may also be the result of direct inactivation of LPS. The purpose of this study was to investigate whether treatment of Porphyromonas endodontalis LPS with calcium hydroxide alters its biological action as measured by human PMN secretion of IL-1 and TNF-$\alpha$, and it was compared with Escherichia coli LPS. P. endodontalis ATCC 35406 was cultured in anaerobic condition, and LPS was extracted using the hot-phenol water extraction method and purified. Purchased E. coli LPS was also purified. 100 $\mu\textrm{g}$/ml of each LPS in pyrogen free water were incubated with 25mg/ml Ca(OH)$_2$ at 37$^{\circ}C$ for 7 days. The supernatants were subjected to ultrafiltration, and the isolates were lyophilized and weighed. PMNs were obtained from peripheral blood by centrifugation layered over Lymphoprep. The cells were resuspended (4$\times$10$^6$ cells/ml) in RPMI 1640 followed by treatment with various concentrations of LPS (0, 0.1, 1, 10$\mu\textrm{g}$/ml) for 24 hours at 37$^{\circ}C$ in 5% $CO_2$ incubator. The supernatants of cells were collected and the levels of IL-1$\alpha$, IL=1$\beta$ and TNF-$\alpha$ were measured by enzyme-linked immunosorbent assay. The results were as follows ; 1. The levels of IL-1$\alpha$, IL-1$\beta$, TNF-$\alpha$ from PMN treated with each LPS were significantly higher than those released from unstimulated PMN of the control group (p<0.05). 2. The levels of all three cytokines released from PMN stimulated with each calcium hydroxide treated LPS were significantly lower than those released from PMN stimulated with each untreated LPS (p<0.05), while they were not significantly different from those released from unstimulated PMN of the control group (p>0.05) 3. The levels of secretion for all three cytokines were affected in a dose-dependent manner in PMN stimulated with each LPS (p<0.05), but not in PMN stimulated with each calcium hydroxide treated LPS (p>0.05). 4. The levels of all three cytokines released from PMN stimulated with p. endodontalis LPS were significantly lower than those released from PMN stimulated with E coli LPS (p<0.05).

Effect of Peking-Duck By-Product Extracts Supplemented with Medicinal Herbs on Serum Heavy Metal Levels and Blood Parameters of Rats Exposed to Lead and Mercury (한약재를 첨가한 오리부산물 추출액이 납과 수은에 노출된 흰쥐 혈청의 중금속 및 혈액지표에 미치는 영향)

  • Park, Sung-Hye;Shin, Eon-Hwan;Park, Sung-Jin;Ran, Jong-Hyun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.4
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    • pp.476-483
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    • 2005
  • This experiment was planned to develop a functional supplement by food resources to prevent and lessen the deleterious effects caused by environmental pollutants such as polluted food, air, water and heavy metals. The goal of this study was to investigate the effects of peking-duck extracts supplemented with six kinds of medicinal herbs (DJ) on the intoxication of lead and mercury in rats. Sprague-Dawley rat weighing $150g\pm15g$ g, were randomly assigned to 5 groups, basal diet only (NCG), heavy metal without DJ injection (HCG), heavy metals and DJ (3 mg/mL) injection (HMLD), heavy metal and DJ (30 mg/mL) injection (HMMD), heavy metal and D] (300 mg/mL) injection (HMHD). Mecury (Hg) and lead (Pb) injected at the level of 50 ppm for 17 days. Also DJ oral feeding was continued for 31 days. The result of this study were as follows; Food intake and body weight gain in heavy metal administered groups were lower than those of control group (NCG). The activities of GOT, GPT and BUN level were significantly reduced in DJ-treated groups as compared to HCG. DJ was shown to suppress the accumulation of Hg and Pb in serum. The results suggest that DJ might have protective effect on Hg and Pb intoxication.

Radioprotective Effects of Post-Treatment with Hesperetin against γ-Irradiation-Induced Tissue Damage and Oxidative Stress in BALB/c Mice (BALB/c 마우스에서 감마선 조사로 유도된 조직 손상과 산화적 스트레스에 대한 헤스페레틴 투여 후의 방사선방호 효과)

  • Kang, Jung Ae;Nam, You Ree;Rho, Jong Kook;Jang, Beom-Su;Chung, Young-Jin;Park, Sang Hyun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.5
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    • pp.657-663
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    • 2015
  • Ionizing radiation induces cell damage through formation of reactive oxygen species. The present study was designed to evaluate the protective effects of post-treatment with hesperetin against ${\gamma}$-irradiation-induced cellular damage and oxidative stress in BALB/c mice. Healthy female BALB/c mice were exposed to ${\gamma}$-irradiation and administered hesperetin (25 mg/kg and 50 mg/kg, b.w., orally) for 7 days after 6 Gy of ${\gamma}$-irradiation. Exposure to ${\gamma}$-irradiation resulted in hematopoietic system damage manifested as decreases in spleen indexes and WBC count. In addition, hepatocellular damage characterized by increased levels of aspartate aminoransferase (AST) and alanine aminotransferase (ALT) in plasma. However, post-irradiation treatment with hesperetin provided significant protection against hematopoietic system damage and decreased AST and ALT levels in plasma. The results indicate that ${\gamma}$-irradiation induced increases in lipid peroxidation and xanthine oxidase (XO) as well as decreases in antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase) and glutathione (GSH) in the liver. These effects were also attenuated by post-treatment with hesperetin, which decreased lipid peroxidation and XO as well as increased antioxidant enzymes and GSH. These results show that post-treatment with hesperetin offers protection against ${\gamma}$-irradiation-induced tissue damage and oxidative stress and can be developed as an effective radioprotector during radiotherapy.

Characterization of Arsenic Immobilization in the Myungbong Mine Tailing (명봉광산의 광미 내 비소의 고정화 특성 연구)

  • Lee, Woo-Chun;Jeong, Jong-Ok;Kim, Ju-Yong;Kim, Soon-Oh
    • Economic and Environmental Geology
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    • v.43 no.2
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    • pp.137-148
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    • 2010
  • The Myoungbong mine located in Boseong-gun, Jellanamdo consists of Au-Ag bearing quartz veins which filled the fissures of Bulguksa granitic rocks of Cretaceous. The tailings obtained from the Myungbong mine were used to investigate the effects of various processes, such as oxidation of primary sulfides and formation(alteration) of secondary and/or tertiary minerals, on arsenic immobilization in tailings. This study was conducted via both mineralogical and chemical methods. Mineralogical methods used included gravity and magnetic separation, ultrasonic cleaning, and instrumental analyses(X-ray diffractometry, energy-dispersive spectroscopy, and electron probe microanalyzer) and aqua regia extraction technique for soils was applied to determine the elemental concentrations in the tailings. Iron (oxy)hydroxides formed as a result of oxidation of tailings were identified as three specific forms. The first form filled in rims and fissures of primary pyrites. The second one precipitated and coated the surfaces of gangue minerals and the final form was altered into yukonites. Initially, large amounts of acid-generating minerals, such as pyrite and arsenopyrite, might make the rapid progress of oxidation reactions, and lots of secondary minerals including iron (oxy)hydroxides and scorodite were formed. The rate of pH decrease in tailings diminished, in addition, as the exposure time of tailings to oxidation environments was prolonged and the acid-generating minerals were depleted. Rather, it is speculated that the pH of tailings increased, as the contribution of pH neutralization reactions by calcite contained in surrounding parental rocks became larger. The stability of secondary minerals, such as scorodite, were deteriorated due to the increase in pH, and finally arsenic might be leached out. Subsequently, calcimn and arsenic ions dissociated from calcites and scorodites were locally concentrated, and yukonite could be grown tertiarily. It is confirmed that this tertiary yukonite which is one of arsenate minerals and contains arsenic in high level plays a crucial role in immobilizing arsenic in tailings. In addition to immobilization of arsenic in yukonites, the results indicate that a huge amount of iron (oxy)hydroxides formed by weathering of pyrite which is one of typical primary minerals in tailings can strongly control arsenic behavior as well. Consequently, this study elucidates that through a sequence of various processes, arsenic which was leached out as a result of weathering of primary minerals, such as arsenopyrite, and/or redissolved from secondary minerals, such as scorodite, might be immobilized by various sorption reactions including adsorption, coprecipiation, and absorption.

[ 137Cs] and 40K Activities of Foodstuffs Consumed in Jeju (제주지역에서 소비되는 식품 중 137Cs과 40K 방사능 농도)

  • Kang, Tae-Woo;Hong, Kyung-Ae;Park, Won-Pyo;U., Zang-Kual
    • Korean Journal of Environmental Agriculture
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    • v.23 no.1
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    • pp.52-58
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    • 2004
  • This work was conducted to provide the reference data of radioactivity in the foodstuffs at a radiological emergency situation in Jeju Island The sampled foodstuffs were agricultural (31), livestock (6), marine (12) and forest products (4), and processed foods (3) consumed by Jeju Islanders. $^{137}Cs$ and $^{40}K$ activities were determined by HPGe r-ray spectromety. The activity ranges of $^{137}Cs$ was ${\sim}650\;mBq/kg$ fresh in the agricultural products, ${\sim}131\;mBq/kg$. fresh in the livestock, ${\sim}834\;mBq/kg$ fresh in the forest, ${\sim}253\;mBq/kg$ fresh in the marine and $32.0{\sim}483\;mBq/kg$. fresh in the processed foods (tea). In case of $^{40}K$ the activity was $16.6{\sim}542\;Bq/kg$. fresh in the agricultural products, $39.1{\sim}294\;Bq/kg$ fresh in the livestock, $85.5{\sim}116\;Bq/kg$ fresh in the forest, $50.1{\sim}657\;Bq/kg$ fresh in the marine, and $33.6{\sim}1,065\;Bq/kg$ fresh in the processed foods (tea). The highest activity of $^{137}Cs$, 834mBq/kg fresh was observed in oak mushroom and $^{40}K$ 1,065 Bq/kg fresh in coffee. Annual effective doses of $^{137}Cs$ and $^{40}K$ by intake of foodstuffs per capita were the following order; agricultural products (66,543 nSv) > livestock products (19,311 nSv) > processed foods (6,648 nSv) > marine products (6,579 nSv) > forest products (860 nSv). Therefore, total annual effective dose was summed 99,941 nSv which is quite low level comparing to the annual effective dose by external exposure, 2,400,000 nSv. The data obtained in this study can be useful for monitoring whether the foodstuffs are contaminated or not at an emergency radiation accident, and showed that the foodstuffs consumed in Jeju are safe in terms of annual effective dose of $^{137}Cs$ and $^{40}K$

Post-thaw Development of Rabbits Pronuclear Embryos by Cryopreservation (토끼 전핵배의 동결보존 후 배발달률)

  • 강다원;조성근;한재희;곽대오;이효종;최상용;박충생
    • Korean Journal of Animal Reproduction
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    • v.23 no.1
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    • pp.75-84
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    • 1999
  • This study assessed development in vitro of pronuclear(PN) stage embryos cryopreserved by the method of either vitrification or slow freezing, by using of different cryoprotectants, and equilibration and cooling rate, in rabbit. Ethyleneglycol- ficoll- sucrose(EFS) or ethyleneglycol- polyvinylpyrrolidone - galactose- (EPG-I) for vitrification, and EPG- II for slow freezing as cryoprotectant were used. The pronuclear embryos were exposed to EFS for 0 to 5 min and diluted with D-PBS and/or pre-dilution with 0.5 M sucrose. To examine the viability of frozen-thawed embryos, PN embryos were co-cultured with bovine oviductal epitherial cell(BOEC) for 5 days to hatching blastocyst stage in 39 $^{\circ}C$ 5% $CO_2$incubator. The results obtained were as follows: The dilution with 0.5 M sucrose and D-PBS after the exposure to EFS for 1.0 min resulted in no significant(P<0.05) decrease in the development of PN embryos to hatching blastocyst(72.0%), compared with controls. The development of PN embryos cryopreserved to hatching blastocyst was not significantly (P<0.05) different between EFS for 1.0 min(72.0%), EPG-I for 1.0 min(72.0%) and EPG-II for 30 min(66. 7%). The post-thaw development of PN embryos to hatching blastocyst was similarly very low as 6.1% and 11.5% in vitrification with EFS and slow freezing with EPG-II, respectively. The incidence of post-thaw zona-crack in PN embryos cryopreserved by slow freezing with plunging to liquid nitrogen at -35$^{\circ}C$ was signicantly(P<0.05) higher(25.0%), compared with -85$^{\circ}C$ (1.9%). These results indicated that the rabbit PN embryos could be cryopreserved with either vitrification or slow freezing procedure, and frozen PN embryos could be successfully developed in vitro to haching blastocyst. but the post-thaw development of cryopreserved PN embryos was still very low under the present conditions.

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