• Title/Summary/Keyword: Activity levels

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Effect of Rosemary and Clove Essential Oils on Quality and Flavor Compounds of Fried Korean Native Chicken Thigh Meat (로즈마리와 클로브 에센셜 오일의 항산화 특성과 토종닭 후라이드 치킨의 품질특성 및 풍미성분에 미치는 영향)

  • Soomin Oh;Yousung Jung;Sangrok Lee;Hee-Jeong Lee;Dongwook Kim;Hyo-Jun Choo;Dong-Jin Shin;Aera Jang
    • Korean Journal of Poultry Science
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    • v.50 no.3
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    • pp.143-159
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    • 2023
  • The study aimed to evaluate the antioxidative effects of rosemary (Rosmarinus officinalis L.) and clove (Syzgyium aromaticum L.) essential oils on fried Korean native thigh meat, including their impact on processed characteristics and flavor compounds. Clove essential oil showed higher DPPH scavenging activity, FRAP and total phenol content compared to rosemary essential oil (P<0.05). The treatments with the addition of 0.005% and 0.01% rosemary (0.005RB and 0.01RB) and clove (0.005CB and 0.01CB) essential oils to the batter weight compared to control that did not include essential oils in batter. The addition of rosemary and clove essential oils to fried Korean native chicken thigh meat did not significant affect proximate composition, pH, TBARS, sensory characteristics. Except for 0.005CB, treatments adding essential oils decreased cooking loss (P<0.05) and 0.005CB showed significantly higher pick-up value than control. Addition of clove essential oil in fried Korean native chicken thigh meat resulted in higher levels of arachidonic acid compared to control (P<0.05). Volatile organic compounds (VOCs) analysis showed that addition of rosemary essential oil might mask its own VOCs, while clove essential oil addition reduced some pyrazine compounds. Although addition of rosemary and clove essential oil did not have significant sensory characteristics on fried Korean native chicken thigh meat, instrumental analysis revealed changes in the compounds that influenced flavor. Further studies are required to evaluate the stability of flavor and sensory characteristics of fried Korean native chicken thigh meat with added essential oils during storage.

Analysis of health behavior, mental health, and nutritional status among Korean adolescents before and after COVID-19 outbreak: based on the 2019-2020 Korea National Health and Nutrition Examination Survey (COVID-19 전·후 한국 청소년의 건강행태, 정신건강 및 영양상태 분석: 국민건강영양조사 2019-2020년 자료를 활용하여)

  • Misun Lee ;Sarang Jeong ;Chong-Su Kim ;Yoon Jung Yang
    • Journal of Nutrition and Health
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    • v.56 no.6
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    • pp.667-682
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    • 2023
  • Purpose: This study aimed to investigate the changes in health behavior, mental health, and nutritional status of Korean adolescents before and after the coronavirus disease 2019 (COVID-19) pandemic outbreak. Methods: A total of 800 adolescents (12~18 years old) who participated in the 2019-2020 Korea National Health and Nutrition Examination Survey (KNHANES) were included as study subjects and divided into four groups (204 middle school boys, 172 middle school girls, 219 high school boys, and 205 high school girls). The 2019 and 2020 KNHANES data were classified into data collected before and after the COVID-19 outbreak, respectively. Results: After the COVID-19 pandemic outbreak, middle school boys showed an increased tendency toward becoming overweight and obese, with significantly increased levels of diastolic blood pressure and insulin. While there was no major change in the subjective health status among adolescents, the high school boys showed a significantly decreased physical activity after COVID-19 outbreak. Moreover, the proportion of middle school students feeling a little stressed significantly increased after the COVID-19 outbreak. The rate of skipping breakfast significantly increased in middle school girls, but the rate of having lunch with companions significantly increased among all adolescents after the COVID-19 outbreak. However, the intake of milk, vegetables, fruits, seaweeds, and pulses significantly decreased, although the intake of sugars, beverages, and seasonings significantly decreased as well, during this period. These changes may lead to an increased proportion of adolescents with insufficient intake of nutrients, including potassium, vitamin C, and riboflavin. Conclusion: These results highlight the impact of COVID-19 on comprehensive changes in physical and mental health status, lifestyle behavior, and nutritional status in adolescents, suggesting the need for targeted prevention and intervention for physical and mental well-being during the pandemic.

Production of highly enriched GABA through Lactobacillus plantarum fermentation of katsuobushi protein hydrolyzate made from Dendropanax morbiferus extract fermented by Bacillus subtilis (황칠나무 추출물의 고초균 발효물로 제조된 가쓰오부시 단백가수분해물의 Lactobacillus plantarum 발효를 통한 고농도 GABA 생산)

  • Yu-Jeong An;Nak-Ju Sung;Sam-Pin Lee
    • Food Science and Preservation
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    • v.30 no.1
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    • pp.146-154
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    • 2023
  • To develop a multi-functional ingredient, the bioconversion of katsuobushi protein was optimized using Bacillus subtilis HA and Lactobacillus plantarum KS2020. The Dendropanax morbiferus extract (DME) culture with protease activity (102 unit/mL) was prepared by B. subtilis with 2% glucose and 1% skim milk through one day of alkaline fermentation. Katsuobushi protein was effectively hydrolyzed by the DME culture at 60℃ for 3 hours, resulting in a tyrosine content of 156.85 mg%. Subsequently, a second lactic acid fermentation was carried out with 10% monosodium glutamate (MSG) using L. plantarum KS2020 to produce higher levels of GABA. Following co-cultivation for three days, DME exhibited a pH of 8.3 (0% acidity). After seven days, the viable cell count of L. plantarum increased to 9.33 CFU/mL, but viable Bacillus cells were not detected. Taken together, a multi-functional ingredient with enriched GABA, peptides, probiotics, and umami flavor was developed through lactic acid fermentation using hydrolyzed katsuobushi protein. These results indicate that katsuobushi protein could be used as a byproduct to produce a palatable protein hydrolysate using alkaline-fermented DME culture as a proteolytic enzyme source.

Characteristics and anti-obesity effect of fermented products of coffee wine (커피발효물의 발효특성 및 항비만 효과)

  • So Hyun Park;Hyeon Hwa Oh;Do Youn Jeong;Young-Soo Kim
    • Food Science and Preservation
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    • v.30 no.4
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    • pp.703-715
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    • 2023
  • This study was conducted to investigate the fermentation characteristics and anti-obesity effects of acetic acid fermentation products of coffee wine. The live cell counts, soluble solids, pH and total acidity of the acetic acid unfermented coffee wine (AUFCW; day 0, before fermentation) were 6.35 log CFU/mL, 8.10 °Brix, 3.88, and 1.29%, respectively, while the acetic acid fermented coffee wine (AFCW; day 15, after fermentation) were 4.40 log CFU/mL, 8.57 °Brix, 3.07, and 7.45%, respectively. Pancreatic lipase inhibitory activity tended to increase as the acetic acid fermentation period increased. The anti-obesity effects of AFCW on 3T3-L1 cells, which was induced by MDI, were evaluated based on the lipid accumulation rate, leptin expression, and fat production-related gene expression (PPAR-γ and SREBP-1c) at the mRNA level. In the case of AFCW, the lipid accumulation rate and leptin expression were decreased to 69.37% and 50.20% at a concentration of 200 ㎍/mL, respectively, and the expression levels of PPAR-γ and SREBP-1c at the mRNA level were decreased to 79.89% and 48.81%, respectively. These results indicate that anti-obesity effect of acetic acid fermentation products could be increased by acetic acid fermentation of coffee wine.

Quality characteristics of different parts of garlic sprouts produced by smart farms during growth (스마트팜 생산 새싹마늘의 부위별 및 생육 기간에 따른 품질 특성)

  • Yu-Ri Choi;Su-Hwan Kim;Chae-Mi Lee;Dong-Hun Lee;Chae-Yun Lee;Hyeong-Woo Jo;Jae-Hee Jeong;Imkyung Oh;Ho-Kyung Ha;Jungsil Kim;Chang-Ki Huh
    • Food Science and Preservation
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    • v.30 no.2
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    • pp.272-286
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    • 2023
  • Garlic sprouts can provide data on functional and food processing materials. This study compared the leaves, bulbs, and roots of garlic sprouts grown on smart farms during two growth periods (20 and 25 days). In addition, data for garlic bulbs grown in open fields were presented as reference materials. All garlic sprouts' total free sugar content decreased as the growth period increased. All plant parts' total organic acid content decreased as the growth period progressed, except for the root section. Potassium, phosphorus, and sulfur content increased during growth in all parts of the garlic sprouts. Alliin content decreased in all parts of the plant over time, whereas thiosulfinate content increased in the roots but decreased in the leaves and bulbs. Total polyphenol content increased in all parts of the plant during the growth period, except for the bulb, whereas the flavonoid content did not change significantly over time. The 2,2-diphenyl-1-picrylhydrazy (DPPH) and 2,2'-azinobis (3-ethylben-zothiazoline 6-sulfonate) (ABTS) free radical scavenging activities, as well as the superoxide dismutase (SOD)-like activity of garlic sprouts were 37.45-65.47%, 59.12-89.81%, and 89.52-98.59%, respectively. These activities tend to decrease during the growth period. Here, we showed that garlic sprouts have higher levels of functional substances and physiological activities than general garlic sprouts. It was also determined that a growth period of 20 days was suitable for garlic sprouts. Data for research on functional and food-processing materials can be obtained by analyzing garlic sprouts produced by smart farms.

The protective effect of Eucommia ulmoides leaves on high glucose-induced oxidative stress in HT-29 intestinal epithelial cells (고당으로 유도된 산화적 스트레스에 대한 두충 잎 추출물의 장 상피 세포 보호 효과)

  • Han Su Lee;Jong Min Kim;Hyo Lim Lee;Min Ji Go;Ju Hui Kim;Hyun Ji Eo;Chul-Woo Kim;Ho Jin Heo
    • Food Science and Preservation
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    • v.31 no.1
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    • pp.183-196
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    • 2024
  • This study investigated the protective effect of the aqueous extract of Eucommia ulmoides leaves (AEEL) against high glucose-induced human colon epithelial HT-29 cells. The 2,2'-azino-bis (3-ethyl benzothiazoline-6-sulfonic acid) (ABTS), 1,1-diphenyl-2-picrylhydrazy (DPPH) radical scavenging activities, ferric reducing/antioxidant power (FRAP), and malondialdehyde (MDA) analyses indicated that AEEL had significant antioxidant activities. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that AEEL increased cell viability against high glucose-, H2O2-, and lipopolysaccharide (LPS)-induced cytotoxicity in HT-29 cells. Also, the 2'-7'-dichlorodihydrofluorescein diacetate (DCF-DA) assay indicated that AEEL decreased intracellular reactive oxygen species (ROS) against high glucose-, H2O2-, and lipopolysaccharide (LPS)-induced cytotoxicity in HT-29 cells. AEEL showed inhibitory activities against α-glucosidase and inhibited the formation of advanced glycation end products (AGEs). AEEL showed significant positive effects on the viability and titratable acidity of L. brevis. The high-performance liquid chromatogram (HPLC) analysis identified chlorogenic acid and rutin as the major compounds of AEEL. These results suggested that AEEL has the potential to be used as a functional food source to suppress blood glucose levels and protect the gut from high glucose-induced oxidative stress.

Influence of Increased Carbon Dioxide Concentration on the Bioluminescence and Cell Density of Marine Bacteria Vibrio fischeri (이산화탄소 농도 증가에 따른 발광미생물의 상대발광량과 밀도변화에 대한 연구)

  • Sung, Chan-Gyoung;Moom, Seong-Dae;Kim, Hye-Jin;Choi, Tae-Seob;Lee, Kyu-Tae;Lee, Jung-Suk;Kang, Seong-Gil
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.15 no.1
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    • pp.8-15
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    • 2010
  • An experiment was conducted to evaluate the biologically adverse effect of increased carbon dioxide in seawater on marine bacteria, Vibrio fischeri. We measured the bioluminescence and cell density at every 6 hours for 24 hours of the whole incubation period after exposing test microbes to a range of $CO_2$ concentration such as 380(Control), 1,000, 3,000, 10,000 and 30,000 ppm, respectively. Significant effect on relative luminescence(RLU) of V. fischeri was observed in treatments with $CO_2$ concentration higher than 3,000 ppm at t=12 h. However, the difference of RLU among treatments significantly decreased with the incubation time until t=24 h. Similar trend was observed for the variation of cell density, which was measured as optical density using spectrophotometer. The results showed that a significant relationship between $CO_2$ concentration and bioluminescence of test microbes was observed for the mean time. However, the inhibition of relative bioluminescence and also cell density could be recovered at the concentration levels higher than 3,000 ppm. The dissolved $CO_2$ can be absorbed directly by cell and it can decrease the intracellular pH. Our results implied that microbes might be adversely affected at the initial growing phase by increased $CO_2$. However, they could adapt by increasing ion transport including bicarbonate and then could make their pH back to normal level. Results of this study could be supported to understand the possible influence on marine bacteria by atmospheric increase of $CO_2$ in near future and also by released $CO_2$ during the marine $CO_2$ sequestration activity.

Relationship Between Usage Needs Satisfaction and Commitment to Apparel Brand Communities: Moderator Effect of Apparel Brand Image (의류 브랜드 커뮤니티의 이용욕구 충족과 커뮤니티 몰입의 관계: 의류 브랜드 이미지의 조절효과)

  • Hong, Hee-Sook;Ryu, Sung-Min;Moon, Chul-Woo
    • Journal of Global Scholars of Marketing Science
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    • v.17 no.4
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    • pp.51-89
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    • 2007
  • INTRODUCTION Due to the high broadband internet penetration rate and its group-oriented culture, various types of online communities operate in Korea. This study use 'Uses and Gratification Approach, and argue that members' usage-needs satisfaction with brand community is an important factor for promoting community commitment. Based on previous studies identifying the effect of brand image on consumers' responses to various marketing stimuli, this study hypothesizes that brand image can be a moderate variable affecting the relationship between usage-needs satisfaction with brand community and members' commitment to brand community. This study analyzes the influence of usage-needs satisfaction on brand community commitment and how apparel brand image affects the relationships between usage-needs satisfactions and community commitments. The hypotheses of this study are proposed as follows. H1-3: The usage-needs satisfaction of apparel brand community (interest, transaction, relationship needs) influences emotional (H1), continuous (H2), and normative (H3) commitments to apparel brand communities. H4-6: Apparel brand image has a moderating effect on the relationship between usage-needs satisfaction and emotional (H4), continuous (H5), and normative (H6) commitments to apparel brand communities. METHODS Brand communities founded by non-company affiliates were excluded and emphasis was placed instead on communities created by apparel brand companies. Among casual apparel brands registered in 6 Korean portal sites in August 2003, a total of 9 casual apparel brand online communities were chosen, depending on the level of community activity and apparel brand image. Data from 317 community members were analyzed by exploratory factor analysis, moderated regression analysis, ANOVA, and scheffe test. Among 317 respondents answered an online html-type questionnaire, 80.5% were between 16 to 25 years old. There were a total of 150 respondents from apparel brand communities(n=3) recording higher-than-average brand image scores (Mean > 3.75) and a total of 162 respondents from apparel brand communities(n=6) recording lower-than-average brand image scores(Mean < 3.75). In this study, brand community commitment was measured by a 5-point Likert scale: emotional, continuous and normative commitment. The degree of usage-needs satisfaction (interest, transaction, relationship needs) was measured on a 5-point Likert scale. The level of brand image was measured by a 5-point Likert scale: strength, favorability, and uniqueness of brand associations. RESULTS In the results of exploratory factor analysis, the three usage-needs satisfactions with brand community were classified as interest, transaction, and relationship needs. Brand community commitment was also divided into the multi-dimensional factors: emotional, continuous, and normative commitments. The regression analysis (using a stepwise method) was used to test the influence of 3 independent variables (interest-needs satisfaction, transaction-needs, and relationship-needs satisfactions) on the 3 dependent variables (emotional, continuous and normative commitments). The three types of usage-needs satisfactions are positively associated with the three types of commitments to apparel brand communities. Therefore, hypothesis 1, 2, and 3 were significantly supported. Moderating effects of apparel brand image on the relationship between usage-needs satisfaction and brand community commitments were tested by moderated regression analysis. The statistics result showed that the influence of transaction-needs on emotional commitment was significantly moderated by apparel brand image. In addition, apparel brand image had moderating effects on the relationship between relationship-needs satisfaction and emotional, continuous and normative commitments to apparel brand communities. However, there were not significant moderate effects of apparel brand image on the relationships between interest-needs satisfaction and 3 types of commitments (emotional, continuous and normative commitments) to apparel brand communities. In addition, the influences of transaction-needs satisfaction on 2 types of commitments (continuous and normative commitments) were not significantly moderated by apparel brand image. Therefore, hypothesis 4, 5 and 6 were partially supported. To explain the moderating effects of apparel brand image, four cross-tabulated groups were made by averages of usage-needs satisfaction (interest-needs satisfaction avg. M=3.09, transaction-needs satisfaction avg. M=3.46, relationship-needs satisfaction M=1.62) and the average apparel brand image (M=3.75). The average scores of commitments in each classified group are presented in Tables and Figures. There were significant differences among four groups. As can be seen from the results of scheffe test on the tables, emotional commitment in community group with high brand image was higher than one in community group with low brand image when transaction-needs satisfaction was high. However, when transaction-needs satisfaction was low, there was not any difference between the community group with high brand image and community group with low brand image regarding emotional commitment to apparel brand communities. It means that emotional commitment didn't increase significantly without high satisfaction of transaction-needs, despite the high apparel brand image. In addition, when apparel brand image was low, increase in transaction-needs did not lead to the increase in emotional commitment. Therefore, the significant relationship between transaction-needs satisfaction and emotional commitment was found in only brand communities with high apparel brand image, and the moderating effect of apparel brand image on this relationship between two variables was found in the communities with high satisfaction of transaction-needs only. Statistics results showed that the level of emotional commitment is related to the satisfaction level of transaction-needs, while overall response is related to the level of apparel brand image. We also found that the role of apparel brand image as a moderating factor was limited by the level of transaction-needs satisfaction. In addition, relationship-needs satisfaction brought significant increase in emotional commitment in both community groups (high and low levels of brand image), and the effect of apparel brand image on emotional commitment was significant in both community groups (high and low levels of relationship-needs satisfaction). Especially, the effect of brand image was greater when the level of relationship-needs satisfaction was high. in contrast, increase in emotional commitment responding to increase in relationship-needs satisfaction was greater when apparel brand image is high. The significant influences of relationship-needs satisfaction on community commitments (continuous and normative commitments) were found regardless of apparel brand image(in both community groups with low and high brand image). However, the effects of apparel brand image on continuous and normative commitments were found in only community group with high satisfaction level of relationship-needs. In the case of communities with low satisfaction levels of relationship needs, apparel brand image marginally increases continuous and normative commitments. Therefore, we could not find the moderating effect of apparel brand image on the relationship between relationship-needs satisfaction and continuous and normative commitments in community groups with low satisfaction levels of relationship needs, CONCLUSIONS AND IMPLICATIONS From the results of this study, we draw several conclusions; First, the increases in usage-needs satisfactions through apparel brand communities result in the increases in commitments to apparel brand communities, wheres the degrees of such relationship depends on the level of apparel brand image. That is, apparel brand image is a moderating factor strengthening the relationship between usage-needs satisfaction and commitment to apparel brand communities. In addition, the effect of apparel brand image differs, depending on the level and types of community usage-needs satisfactions. Therefore, marketers of apparel brand companies must determine the appropriate usage-needs, depending on the type of commitment they wish to increase and the level of their apparel brand image, to promote member's commitments to apparel brand communities. Especially, relationship-needs satisfaction was very important factor for increasing emotional, continuous and normative commitments to communities. However the level of relationship-needs satisfaction was lower than interest-needs and transaction-needs. satisfaction. According to previous study on apparel brand communities, relationship-need satisfaction was strongly related to member's intention of participation in their communities. Therefore, marketers need to develope various strategies in order to increase the relationship- needs as well as interest and transaction needs. In addition, despite continuous commitment was higher than emotional and normative commitments, all types of commitments to apparel brand communities had scores lower than 3.0 that was mid point in 5-point scale. A Korean study reported that the level of members' commitment to apparel brand community influenced customers' identification with a brand and brand purchasing behavior. Therefore, marketers should try to increase members' usage-needs satisfaction and apparel brand image as the necessary conditions for bringing about community commitments. Second, marketers should understand that they should keep in mind that increasing the level of community usage needs (transaction and relationship) is most effective in raising commitment when the level of apparel brand image is high, and that increasing usage needs (transaction needs) satisfaction in communities with low brand image might not be as effective as anticipated. Therefore, apparel companies with desirable brand image such as luxury designer goods firms need to create formal online brand communities (as opposed to informal communities with rudimentary online contents) to satisfy transaction and relationship needs systematically. It will create brand equity through consumers' increased emotional, continuous and normative commitments. Even though apparel brand is very famous, emotional commitment to apparel brand communities cannot be easily increased without transaction-needs satisfaction. Therefore famous fashion brand companies should focus on developing various marketing strategies to increase transaction-needs satisfaction.

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Matrix Metalloproteinase in Idiopathic Pulmonary Fibrosis (특발성 폐섬유화증환자의 기관지폐포세척액 및 폐포대식세포 배양액의 Matrix metalloproteinase의 변화)

  • Park, Joo-Hun;Shim, Tae-Sun;Lim, Chae-Man;Koh, Youn-Suck;Lee, Sang-Do;Kim, Woo-Sung;Kim, Won-Dong;Kim, Dong-Soon
    • Tuberculosis and Respiratory Diseases
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    • v.51 no.4
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    • pp.303-314
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    • 2001
  • Background : Matrix metalioproteinase(MMP)-2 and MMP-9 have been known to play an important role in cell migration and the tissue remodeling process by type IV collagen lysis, a major component of the basement membrane. Intra-alveolar fibrosis, secondary to an injury to the basement membrane of the alveolar epithelial lining, is a major process in the pathogenesis of idiopathic pulmonary fibrosis(IPF). Therefore, MMP-2 and MMP-9 was hypothesized to play an important role in IPF pathogenesis. As a result, their level may reflect the activity or prognosis. Method : Forty one progressive IPF patients(age $59.82{\pm}1.73$ years, M:F=23:18), 16 patients with stable IPF for more than one year without therapy(age : $63.6{\pm}2.8$ years, M:F=13:3), and 7 normal controls were enrolled in this study. The MMP-2 and MMP-9 levels in the BAL fluid and alveolar macrophage conditioned media(AM-CM) were measured by zymography and the TIMP-1 level was measured by ELISA. Results : 1) The MMP-2 level in BALF was highest in the progressive IPF group ($1.36{\pm}0.28$) followed by the stable group ($0.46{\pm}0.13$) and the controls ($0.08{\pm}0.09$), which was statistically significant. The MMP-9 level of the IPF ($0.31{\pm}0.058$) and the stable group ($0.22{\pm}0.078$) were higher than that of the control group ($0.002{\pm}0.004$). In the AM-CM, only MMP-9 was detected, which was significantly higher in IPF group ($0.80{\pm}0.1O$) than in the control group($0.23{\pm}0.081$). The TIMP-1 level was also higher in both the IPF ($36.34{\pm}8.62\;{\mu}g/ml$) and stable group ($20.83{\pm}8.53\;{\mu}g/ml$) compared to the control group ($2.80{\pm}1.05\;{\mu}g/ml$) (p<0.05). 3) There was a correlation between the MMP-2 level in the BALF with the total cell number(r=0.298) and neutrophils(r=0.357) (p<0.05), and the MMP-9 level with the number of neutrophils (r=0.407) and lymphocytes (r=0.574)(p<0.05). The TIMP-1 level correlated with the total number of cell (r=0.338, p<0.05) and neutrophils(r=0.449, p=0.059). Conclusion : Both MMP and TIMP appear to play an important role in IPF pathogenesis, and their level may reflect the disease activity.

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Studies on Ripening Physiology of Rice plant. -I Difference in Ripening Structure between Jinheung and IR667 (수도(水稻)의 등숙생리(登熟生理)에 관(關)한 연구(硏究) -I 진흥(振興)과 IR667의 등숙구조비교(登熟構造比較))

  • Kwon, Hang Gwang;Park, Hoon
    • Korean Journal of Soil Science and Fertilizer
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    • v.5 no.2
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    • pp.65-74
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    • 1972
  • A local rice variety, Jinheung and newly bred IR667-Suwon 214 were grown in $5m^2$ concret pot with two spacings and two nitrogen levels and their ripening structure and its function were comparatively investigated to elucidate the causes of unusually low ripened grain ratio of IR667 lines. The following differences between two varieties were found. 1. Though IR667 had much lower ripened grain ratio (64%) than Jinheung (85%) grain yield(790 kg/10a) of IR667 was higher than that (760 kg/10a) of Jinheung. 2. Number of ripined grain per net assimiration rate (NAR) at 10 days after heading was a little higher in IR667 (6,490) than in Jinheung (6,360) consiting to lower grain weight ($29.9{\times}10^{-3}g$) in IR667 than $31.2{\times}10^{-3}g$ of Jinheung. But number of total grain per NAR was much higher (10,530) in IR667 than 7,290 of Jinheung indicating that it was the probable cause of low ripened grain ratio of IR667. 3. Extinction coeificient (K) was 0.115 in IR667 and 0.200 in Jinheung, thus IR667 could construct greater ripening structure per unit area. 4. Number of grain per LAI was decreased with increasing LAI at heading and the decreasing rate was similar for both IR667 and Jinheung. 5. Critical leaf area index at which crop growth rata (CGR) is maximum was 6.5 for IR667 and 5.2 for Jinheung. Below 5.2 of LAI net assimilation rate was always higher an Jinheung throughout the growing season. 6. The estimated optimum leaf area index having maximum grain yield was 7.4 for IR667 and 6.2 for Jinheung at 10 days after heading. However, actual leaf area index was 6.2 for IR-667 and 4.7 for Jinheung and these were even below critical leaf area index. 7. The decrease of LAI during ripening period was great in IR667 but photosynthesis per $m^2$ was decreased more rapidly in Jinheung. 8. Net assimilation rate (NAR) decreased with the increase of LAI at any time of ripening period. The decreasing rate of NAR with the increase of LAI was greater in IR667 with ripening. The greater decreasing rate of NAR in IR667 seemed to be attributed to low photosynthetic activity and high respiratory loss due to the requirement of higher optimum temperature of ripening. 9. Grain yield-ripened grain ratio curve showed less contribution of dry matter yield after heading to grain yield in IR667 than in Jinheung due to unfavorable ripening environment(specialy air temperature) indicating that yield of IR667 could most effectively increased through the improvement of ripening environment.

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