• Title/Summary/Keyword: school stress

Search Result 7,328, Processing Time 0.038 seconds

Comparison of proximate compositions, antioxidant, and antiproliferative activities between blueberry and Sageretia thea (Osbeck) M.C.Johnst fruit produced in Jeju Island (제주산 블루베리와 상동열매의 일반성분, 항산화 및 항증식 활성 비교)

  • Ko, Gyeong-A;Koh, So Yae;Ryu, Ji-yeon;Cho, Somi Kim
    • Journal of Applied Biological Chemistry
    • /
    • v.60 no.2
    • /
    • pp.161-171
    • /
    • 2017
  • This study was aimed to evaluate and compare the proximate composition, antioxidant and antiproliferative activities of Sageretia thea (Osbeck) M.C.Johnst (S. thea) fruit and blueberry. The calorific value, crude protein, crude fat, crude ash, and carbohydrate were higher in S. thea fruit than in blueberry. S. thea fruit and blueberry have different profile of free sugars, in which amounts of fructose, glucose, and maltose were much higher in S. thea fruit than in blueberry. The methanol extracts of S. thea fruit contain higher amounts of total polyphenol and anthocyanin compared to those of blueberry extracts. In additions, 2,2-diphenyl-1-picrylhydrazyl (DPPH), alkyl, and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging activities are greater in S. thea fruit extracts. Ethyl acetate fractions and n-butanol fractions of S. thea fruit and blueberry show the most potent scavenging activity in DPPH-, alkyl-, and ABTS-radical scavenging assay. The ethyl acetate fractions of S. thea fruit and blueberry are the richest fraction in polyphenol contents while the n-butanol fractions of those are the highest fraction in anthocyanin contents. Furthermore, both S. thea fruit and blueberry extracts protect human dermal fibroblast cells against a $H_2O_2$-induced oxidative stress. The antiproliferative activities of n-hexane and chloroform fraction from S. thea fruit and blueberry were observed in AGS human gastric cancer and MDA-MB-231 human breast cancer cells. Therefore, our results suggest for the first time that the antioxidant and antiproliferative activities of S. thea fruit is comparable to that of blueberry and the nutritional value of the former is even superior to that of the latter.

Biodiversity Conservation and the Yellow Sea Large Marine Ecosystem Project (생물다양성 보전과 황해 광역 해양생태계 관리계획)

  • Walton, Mark
    • Journal of the Korean Society for Marine Environment & Energy
    • /
    • v.13 no.4
    • /
    • pp.335-340
    • /
    • 2010
  • The paper describes the objectives of Yellow Sea Large Marine Ecosystem (YSLME) project, focusing on procedural and practical aspects. YSLME is a highly productive sea yet possibly one of the most impacted large marine ecosystems, in terms of anthropogenic stressors, due the enormous coastal population. The aim of the YSLME project is the reduction of ecosystem stress through identification of the environmental problems in the Transboundary Diagnostic Analysis (TDA) that are then addressed in the Strategic Action Programme (SAP). One of the major problems found to be affecting biological diversity is habitat modification through wetland reclamation, conversion and degradation. Since the early 1900's more than 40% of intertidal wetlands have been reclaimed in Korea, and 60% of Chinese coastal wetlands have been converted or reclaimed. Damaging fishing practices, pollution and coastal eutrophication have further degraded the coastal environment reducing the biological diversity. To combat this loss, the YSLME project has mounted a public awareness campaign to raise environmental consciousness targeted at all different levels of society, from politicians at parliamentary workshops, local government officer training events, scientific conferences and involvement of scientists in the project research and reporting, to university and high school students in our visiting internship programmes and environmental camps. We have also built networks through the Yellow Sea Partnership and by liaising and working with other environmental organizations and NGOs. NGO's are recognised as important partners in the environmental conservation as they already have extensive local networks that can be lacking in international organisations. Effective links have been built with many of these NGOs through the small grants programme. Working with WWF's YSESP project and other academic and research institutions we have conducted our own biodiversity assessments that have contributed to the science-based development of the SAP for the YSLME. Our regional targets for biodiversity outlined in the SAP include: Improvements in the densities, distributions and genetic diversity of current populations of all living organisms including endangered and endemic species; Maintenance of habitats according to standards and regulations of 2007; and a reduction in the risk of introduced species. Endorsement of the SAP and its successful implementation, during the proposed second phase of the YSLEM project, will ensure that biological diversity is here to benefit future generations.

The Improvement of Chaga Mushroom (Inonotus Obliquus) Extract Supplementation on the Blood Glucose and Cellular DNA Damage in Streptozotocin-Induced Diabetic Rats (Streptozotocin으로 유발한 당뇨쥐에 있어서 차가버섯(Inonotus Obliquus)의 혈당 및 DNA 손상 개선효과)

  • Park, Yoo-Kyoung;Kim, Jung-Shin;Jeon, Eun-Jae;Kang, Myung-Hee
    • Journal of Nutrition and Health
    • /
    • v.42 no.1
    • /
    • pp.5-13
    • /
    • 2009
  • Mushrooms have become a largely untapped source of powerful new pharmaceutical products that poses anti-inflammatory, and antimutagenic, and antioxidant activities. The antioxidant effects of the mushroom may be partly explained by protecting cellular components against free radical. The aim of this study was to investigate the protective effect of chaga mushroom against diabetes, via the mitigation of oxidative stress and reduction of blood glucose, in streptozotocin-induced diabetic rats. Rats were rendered diabetic by intravenous administration of STZ through tail at a dose of 50 mg/kg. Animals were allocated into four groups with 8 rats each. The control and diabetic control group were fed with standard rat feed. The other diabeic groups, the low chaga extract group and the high chaga extract group were fed ad libitum using 0.5 g/kg and 5 g/kg of chaga mushroom extract, respectively, for 4 weeks. The blood glucose levels in the two chaga extract groups showed a tendency to decrease but did not reach statistical significance after the supplementation. Leukocyte DNA damage, expressed as tail length, was found to be significantly lower in the high chaga extract group than in the diabetic control group (p > 0.05). Plasma level of total radical-trapping antioxidant potential (TRAP) was tend to be higher in the high chaga extract group compared with the diabetic control group. Erythrocyte antioxidant enzyme activities of two groups did not differ. Although we did not obtain beneficial effect on lowering blood glucose levels in the STZ-induced diabetic rats, this results suggest that the chaga mushroom extracts may initially act on protecting endogenous DNA damage in the short-term experiment.

An Empirical Testing of Employee Attchment Model: A Comprison of South Korean and U.S. Teachers (조직유착모형의 경험적 적합성에 관한 고찰 - 교사들의 경우를 중심으로 한 한 . 미간 비교연구 -)

  • 조동기
    • Korea journal of population studies
    • /
    • v.19 no.1
    • /
    • pp.139-159
    • /
    • 1996
  • This study comparatively examines a causal model of employee attatchment which focuses on employee's organizational commitment and intent to stay with an organization. This study is based on two separate studies of employee attachment among teachers : the U.S. case of the Chicago Public Schools (CPS) and the South Korean case of the Seoul Educational District (SED). The main purpose of this study is to replicate in Korea the CPS study. A revised model based on the unique characteristics of Korean teachers is also developed and estimated. The Price Mueller model of employee attachment provides the basic theoretical framework for this study. It includes five general classes of variables : 1) employee responses to work variables : job satisfaction, commitment, and intent to stay; 2) psychological stress variables: role ambiguity, role conflict, work overload, and quality of students; 3) social structural variables: autonomy, routinization, distributive justice, and legitimacy; 4) economic structural variables: pay, job security, promotional opportunities, and job opportunities; and 5) work orientation variables : career commitment, normative commitment, work motivation, affectivity, work values, and met expectations. The data was collected through questionnaire survey and a sample of 649 secondary school teachers in Seoul, South Korea, was included in the final analysis. Covariance structure analysis (LISREL) was used to estimate the causal model. The results indicate that the endogenous variables of job satisfaction and commitment play a considerably less important role than in the U.S. model in mediating the effects of the exogenous variables on intent to stay, and the model fails to explain the majority of the variance in intent to stay. In addition, the new variables added to the revised Korean model do not bave significant effects on intent to stay. The structural characteristics of the employment relationship and labor markets associated with Korean teachers forced mobility and closed external markets - are largely accountable for the major differences between the Korean and the U.S. cases. The study suggests that conceptual and empirical work on what produces employee attachment under these structural constraints needs to receive more attention in future studies.

  • PDF

Comparison of the High Concentration Calcium Chloride(CaCl2) Salt Reduction Effect of Soil Amendment Agent and Planting Pennisetum alopecuroides (토양개량제와 수크령 식재에 따른 고농도 염화칼슘 염분저감 효과 비교)

  • Yang, Ji;Park, Jae-Hyeon;Yoon, Yong-Han;Ju, Jin-Hee
    • Korean Journal of Environment and Ecology
    • /
    • v.34 no.4
    • /
    • pp.345-354
    • /
    • 2020
  • The purpose of this study was to investigate the effects of soil amendment treatments, such as hydroball, and active carbon, and planting Pennisetum alopecuroides for reducing calcium chloride (CaCl2) of soil leachate and the growth of Pennisetum alopecuroides. The experiment planted Pennisetum alopecuroides in a plastic pot with a diameter of 10 cm and a height of 9 cm in a greenhouse April-October 2018. The experimental group comprised six treatments, including Non-treatment (Cont.), Hydroball (H), Active carbon (AC), planting Pennisetum alopecuroides (P), hydroball + planting Pennisetum alopecuroides (H + P), and active carbon + planting Pennisetum alopecuroides (AC + P). The dissolution of the CaCl2 concentration 200ml of 10g/L was irrigated once every two weeks. We measured the growth (plant height, leaf length, leaf width, number of leaves), EC, pH, and exchangeable cations (K+, Ca2+, Na+, and Mg2+) according to the high concentration of CaCl2 in the plant and soil leachate. In a treatment with the 'hydroball' amendment, the soil leachate electrical conductivity (EC), and the cation exchangeable were decreased more than those of the control, while the growth of Pennisetum alopecuroides relative growth rate(RGR) increased. Overall, application with the hydroball amendment added the planting of Pennisetum alopecuroides improved the salt reduction effect more than the control group. These results indicate that the application of the soil amendment agent hydroball was suitable soil amendments in accordance with the high concentration of calcium chloride (CaCl2). Also, Planting Pennisetum alopecuroides is expected to be appropriate for salt-tolerant plant for soil affected by deicing salt agents.

Association between Antipsychotic-Induced Restless Legs Syndrome and Glutathione S-Transferase Gst-M1, Gst-T1 and Gst-P1 Gene Polymorphisms (Glutathione S-Transferase (GST) 유전자 다형성과 항정신병약물로 유발된 하지불안증후군의 연관 연구)

  • Kang, Seung-Gul;Park, Young-Min;Kim, Leen;Lee, Heon-Jeong
    • Sleep Medicine and Psychophysiology
    • /
    • v.22 no.1
    • /
    • pp.25-29
    • /
    • 2015
  • Objectives: The pathophysiology of restless legs syndrome (RLS) has not been fully elucidated. Oxidative stress might play a role in the development of RLS and other antipsychotic-induced side effects such as tardive dyskinesia. In the present study, we investigated whether the glutathione S-transferase (GST) gene polymorphisms are associated with antipsychotic-induced RLS in schizophrenia. Methods: We assessed antipsychotic-induced RLS symptoms in 190 Korean schizophrenic patients using the diagnostic criteria of the International Restless Legs Syndrome Study Group. The GST-M1, GST-T1 and GST-P1 loci were analyzed using PCR-based methods. Results: We divided the subjects into 2 groups: those with RLS symptoms (n = 96) and those without RLS symptoms (n = 94). There were no significant differences in the distributions of the GST-M1 genotypes (${\chi}^2=3.56$, p = 0.059), GST-T1 (${\chi}^2=0.51$, p = 0.476) and GST-P1 (${\chi}^2=0.57$, p = 0.821) between the 2 groups. Comparison of the RLS score among genotypes of the GST-M1 (t = -1.54, p = 0.125), GST-T1 (t = -0.02, p = 0.985) and GST-P1 (F = 0.58, p = 0.560) revealed no significant difference. Conclusion: These data suggest that GST gene polymorphisms do not confer increased susceptibility to RLS symptoms in schizophrenic patients. Future studies are necessary to evaluate the possible influences of other candidate genes involved in the reactive oxygen species system.

Effect of Epigallocatechin Gallate on Phosphoinositide 3-kinase/Akt and Glycogen Synthase Kinase-3 Pathway in Oxidative-stressed N18D3 Cells Following $H_2O_2$ Exposure (산화성 손상을 받은 N18D3세포에서 Epigallocatechin gallate가 Phosphoinositide 3-kinase/Akt 및 Glycogen synthase kinase-3경로에 미치는 효과)

  • Koh, Seong Ho;Kwon, Hyug Sung;Oh, Hwa Soon;Oh, Jae Ho;Park, Ynun Joo;Kim, Jun Gyou;Kim, Ki Sok;Kim, Yang Soon;Yang, Ki Hwa;Kim, Seung U.;Kim, Seung H.;Jung, Hai Kwu
    • Korean Journal of Clinical Pharmacy
    • /
    • v.13 no.1
    • /
    • pp.29-39
    • /
    • 2003
  • Neurodegenerative disorders are associated with apoptosis as a causing factor or an inducer. On the other hand, it has been reported that epigallocatechin gallate (EUG), one of antioxidants and flavonoids, and z-VAD-fmk, a nonselective caspase inhibitor, suppress oxidative-radical-stress-induced apoptosis. However, it is not yet known what is the effects of EGCG and z-VAD-fmk on the apoptotic pathway is through phosphoinositide 3-kinase (PI3K), Akt and glycogen synthase kinase-3 (GSK-3) as well as mitochondria, caspase-3 and poly (ADP-ribose) polymerase (PARP). We investigated the effects of EGCG by using $H_2O_2$ treated N18D3 cells, mouse DRG hybrid neurons. Methods: Following 30 min $100\;{\mu}m\;H_2O_2$ exposure, the viability of N18D3 cells (not pretreated vs. EGCG or z-VAD-fmk pretreated) was evaluated by using MTT assay. The effect of EGCG on immunoreactivity (IR) of cytochrome c, caspase-3, PARP, PI3K/Akt and GSK-3 was examined by using Western blot, and was compared with that of z-Y4D-fmk. Results: EGCG or z-VAD-fmk pretreated N18D3 cells showed increased viability. Dose-dependent inhibition of caspase-3 activation accompanied by PARP cleavage were demonstrated by pretreatment of both agents. However, inhibition of cytochrome c release was only detected in EGCG pretreated N18D3 cells. On the pathway through PI3K/Akt and GSK-3, however, the result of Western blot in EGCG pretreated N18D3 cells showed decreased IR of Akt and GSK-3 and increased IR of p85a PI3K, phosphorylated Akt and GSK-3, and contrasted with that in z-VAD-fmk pretreated N18D3 cells showing no changes on each molecule. Conclusion: These data show that EGCG affects apoptotic pathway through upstream signal including PI3K/Akt and GSK-3 pathway as well as downstream signal including cytochrome c and caspase-3 pathway. Therefore, these results suggest that EGCG mediated activation of PI3K/Akt and inhibition GSK-B could be new potential therapeutic strategy for neurodegenerative diseases associated with oxidative injury.

  • PDF

Associations between the Practice of Health Behaviors and Awareness of Metabolic Syndrome among Adults (19-64 years) in the Gwangju-Jeonnam Area: 2010 Community Health Survey (광주 전남지역 성인의(19-64세) 건강생활실천과 대사증후군 인지와의 관련성 - 2010년 지역사회건강조사 자료를 이용하여 -)

  • Chun, In Ae;Ryu, So Yeon;Park, Hyeon Hui;Park, Jong;Han, Mi Ah;Choi, Seong Woo
    • Journal of agricultural medicine and community health
    • /
    • v.38 no.4
    • /
    • pp.217-228
    • /
    • 2013
  • Objective: This study was performed to identify associations between the practice of health behaviors and awareness of metabolic syndrome (MetS) among adults aged 19 to 64 years in the Gwangju-Jeonnam area. Methods: This study utilized data from the 2010 Community Health Survey (CHS). Health behaviors considered in this study were smoking, alcohol drinking, physical activity, low-salt diet, and perception of stress. The index for the health behaviors was calculated as the sum of the practice of each health behavior (range: 0-5). The analysis was weighted with a complex sampling design, and the chi-square test and multiple logistic regression analysis were used to identify the association between the practice of health behaviors and awareness of MetS. Results: A total of 19.8% of the population were aware of MetS. The perception of MetS was statistically significantly associated with healthy behaviors, including nonsmoking (aOR = 1.33, 95% CI = 1.14-1.56), non-high-risk drinking (aOR = 1.54, 95% CI = 1.27-1.88), engagement in physical activity (aOR = 1.48, 95% CI = 1.28-1.72), and a low-salt diet (aOR = 1.30, 95% CI = 1.13-1.51). The ORs of the perception of MetS were significantly higher in patients with a health behavior index of 2 to 3 (aOR = 1.64, 95% CI = 1.01-2.66) and in those with an index of ${\geq}4$ (aOR = 2.47, 95% CI = 1.51-4.04) than in those with an index of 0. Among all health behaviors, physical activity had the highest OR for the perception of MetS (aOR = 1.50, 95% CI = 1.29-1.74). Conclusions: This study revealed associations between health behaviors, especially physical activity, and awareness of MetS. Therefore, integrated health promotion programs may be needed to enhance awareness of MetS and to effectively prevent MetS and non-communicable diseases.

The Effect of Creeping Bentgrass Growth on Greenspeed (그린잔디의 생육이 그린스피드에 미치는 영향)

  • Kwon, Il-Woo;Lee, Dong-Hee;Choi, Byuong-Man;Tae, Hyun-Sook;Shin, Dong-Hyun
    • Asian Journal of Turfgrass Science
    • /
    • v.25 no.2
    • /
    • pp.223-228
    • /
    • 2011
  • This research was performed to investigate change of green speed according to growth of grass, for this, the method of effective green management for improvement of green speed was searched by investigating green density, soil moisture, surface hardness, and mowing height every day for 6 months. As the result of the study, reliability between, green density, soil moisture, surface hardness, mowing height and green speed were measured to be respectively 0.4742, 0.5690, 0.4632, 0.2806, i.e. soil moisture is considered as the factor which affects green speed the most. Therefore, it will be an advantageous environment to maintain soil moisture a little bit low to improve green speed within the range that does not disrupt the growth of green. In case of green density, it is considered to be effective to get a fast green speed when obtaining enough density during May~June, the most vigorous growth period and at the same time green up period. Surface hardness was confirmed that management work as rolling is a considerably effective method to increase hardness. However, rolling gives high stress to the green, combining another management work as regular hilling could be a good alternative. Reliability of green preview and green speed was 0.2806, lower than soil moisture or surface hardness. Through the results, it was confirmed that management of mowing height to be low less than 3.00 mm is helpful to improve green speed, timely, and it is advantageous to manage green speed when adjusting mowing height during the vigorous growth period of bent grass. However, considering the range of mowing height was not various, being 2.9~3.4 mm, henceforth research on investigation of green speed at more various mowing heights would be necessary. Consequently, except mowing height, other three factors, i.e. green density, soil moisture and surface hardness were investigated to have considerable level of reliability on green speed, and it is considered that each factor affects green speed respectively according to green condition and time. Accordingly, in order for the manager to maintain high speed all year round, intensive care for each factor per time unit considering green growth condition is considered to be necessary.

Growth Performances of Some Oak Seedlings according to Soil Moisture Regime and Fertilization (수분(水分) 및 시비처리(施肥處理)에 따른 참나무 실생묘(實生苗)의 생육반응(生育反應))

  • Kim, Chi Moon;Kwon, Ki Won;Moon, Heung Kyu;Park, Hong Joon
    • Korean Journal of Agricultural Science
    • /
    • v.11 no.2
    • /
    • pp.207-217
    • /
    • 1984
  • Seasonal growth performances or root collar diameter and seedling height of Quercus acutissima. Q. mongolica and Q. variabilis were measured at regular intervals of 10 or 15 days after the treatments of some combinations of soil water regime ${\times}$ fertilization. The treatments of soil water regime and fertilization Influenced on the growth performances of seedlings differently with one another in course of time lapse. The growth performances revealed highly significant differences between soil water regimes, between fertilizations and between their interactions after unlike time lapses by species. The effects of soil water regime were exhibited in retard compared with those of fertilization, and to be different outstandingly in the treatments of N or N+P+K fertilization. The limit of soil water potential influencing critically on the growth performances might be estimated to be in -3~-6 bar in all the species. The growth responses were significantly different between N or N+P+K treatment and P or K treatment or control in all the species, and the treatment effects represented more great differences in moist soil water regime than in dry soil water regime. The interactions of soil water regime ${\times}$ fertilization were revealed s lowly with time lapse in all the treatments. The statistical differences of growth responses of root collar diameter according to the treatments were observed in earlier stage compared with those of seedling height. By comparison of the growth responses of the species studied, Q. variabilis and Q. mongolica seemed to be more resistant to moisture stress than Q. acutissima.

  • PDF