• Title/Summary/Keyword: rate of change

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Myocardial Perfusion after Transmyocardial Mechanical Revascularization in Rat Heart Transplant Model, Acute Model (백서 동종이식 심장모델에서 기계적 경심근 혈관재형성의 심근 혈류 개선 효과 : 급성기 모델)

  • Shinn Sung Ho;Chung Won Sand;Kang Jung Ho;Jeon Yang-Bin
    • Journal of Chest Surgery
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    • v.38 no.7 s.252
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    • pp.468-475
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    • 2005
  • Transmyocardial revascularization (TMR) in end stage ischemic heart disease results in variable clinical responses. We investigated the acute effect of early reperfusion and the angiogenesis after formation of the transmyocardial channel in a transplanted rat heart model with acute myocardial infarction. Material and Method: In the 30 transplanted hearts we induced acute myocardial infarction by ligating the proximal left coronary artery and inserted a porous 22G intravenous cannula into the left ventricle. After ten minutes of reperfusion, we removed the cannula. At every stage, we recorded the heart rate, QRS size, and left coronary arterial blood flow using the electrocardiogram and Doppler. One week later the rats were sacrificed and evaluated for the patency of intramyocardial channels and the angiogenesis. Result: The heart rates after ligation and after cannula insertion were $239.1\pm61.7,\;235.8\pm58.0bpm$ respectively, and they were statistically significantly slower than that of before ligation, $277.6\pm40.3bpm\;(p=0.017,\;p=0.007\;respectively)$. QRS sizes before ligation, after ligation, and after cannula insertion were $3.6\pm3.3mm,\;2.8\pm3.3 mm,\;and\;2.4\pm2.2mm,$respectively, and there was no significant difference in the three groups. Doppler findings after ligation showed that average peak and mean values of coronary perfusion were significantly decreased from $2.11\pm0.17kHz,\;1.25\pm0.22kHz\;to\;0.83\pm0.15kHz,\;0.38\pm0.11kHz$(p<0.05 respectively). After insertion of the porous cannula, the average peak and mean values of coronary perfusion were $0.61\pm0.05kHz\;and\;0.33\pm0.05 kHz$ respectively, but there was no statistically significant change compared to values after ligation. In all cases except one, pathologic findings showed no patent channels in the acute stage, however, one case showed the angiogenesis. Conclusion: We confirmed that TMR in a rat heart transplant model did not show blood flow through the channel in the acute stage. However, reperfusion effect in some cases had a potential for angiogenesis.

High-Resolution Paleoproductivity Change in the Central Region of the Bering Sea Since the Last Glaciation (베링해 중부 지역의 마지막 빙하기 이후 고생산성의 고해상 변화)

  • Kim, Sung-Han;Khim, Boo-Keun;Shin, Hye-Sun;Uchida, Masao;Itaki, Takuya;Ohkushi, Kenichi
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.14 no.3
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    • pp.134-144
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    • 2009
  • Paleoproductivity changes in the central part of the Bering Sea since the last glacial period were reconstructed by analyzing opal and total organic carbon (TOC) content and their mass accumulation rate (MAR) in sediment core PC23A. Ages of the sediment were determined by both AMS $^{14}C$ dates using planktonic foraminifera and Last Appearance Datum of radiolaria (L. nipponica sakaii). The core-bottom age was calculated to reach back to 61,000 yr BP. and some of core-top was missing. Opal and TOC contents during the last glacial period varied in a range of 1-10% and 0.2-1.0%, and their average values are 5% and 0.7%, respectively. In contrast, during the last deglaciation, opal and TOC contents varied from 5 to 22% and from 0.8 to 1.2%, respectively, with increasing average values of 8% and 1.0%. Opal and TOC MAR were low ($1gcm^{-2}kyr^{-1}$, $0.2gcm^{-2}kyr^{-1}$) during the last glacial period, but they increased (>5 and >$1gcm^{-2}kyr^{-1}$) during the last deglaciation. High diatom productivity during the last deglaciation was most likely attributed to the elevated nutrient supply to the sea surface resulting from increased melt water input from the nearby land and enhanced Alaskan Stream injection from the south under the restricted sea-ice and warm condition during the rising sea level. On the contrary, low productivity during the last glacial period was mainly due to decreased Alaskan Stream injection during the low sea-level condition as well as to extensive development of sea ice under low-temperature seawater and cold environment.

Changes in Quality Characteristics of Fresh-cut Produce during Refrigerated Storage (냉장 저장 중 신선편이 농산물의 품질특성 변화)

  • Sun, Shih-Hui;Kim, Su-Jin;Kim, Gi-Chang;Kim, Haeng-Ran;Yoon, Ki-Sun
    • Korean Journal of Food Science and Technology
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    • v.43 no.4
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    • pp.495-503
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    • 2011
  • We evaluated the quality characteristics of fresh-cut produce (potato, sweet potato, carrot, radish, zucchini, cucumber, and green bell pepper) washed with sodium hypochlorite, which were vacuum packaged, and stored at 4 and 10$^{\circ}C$. The L-values of the fresh-cut potato and sweet potato decreased during storage. Lower PPO activities of potato and sweet potato were observed at 4$^{\circ}C$ than those at 10$^{\circ}C$ and development of potato and sweet potato browning was delayed at 4$^{\circ}C$. Total aerobic count and coliform increased continuously at 10$^{\circ}C$ during storage. Diced zucchini and shredded sweet potato had the greatest reduction in hardness among the fresh-cut produce during storage. Differences in the rate of quality change were observed according to the kinds and cut types of produce. Thus, a quality maintenance period for each type of fresh-cut produce must be determined, which will lead to the safe use of fresh cut produce in foodservice establishments.

Changes in Benthic Macroinvertebrate Community Before and After Rainy Season in Mountain Valley with Erosion Control Dam (사방댐이 설치된 산지계곡의 장마 전·후 저서성 대형무척추동물 군집변화)

  • An, Chae-Hui;Han, Jung-Soo;Choi, Jun-Kil;Lee, Hwang-Goo
    • Korean Journal of Environment and Ecology
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    • v.34 no.2
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    • pp.121-129
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    • 2020
  • This study investigated the change of benthic macroinvertebrates community due to erosion control dams installed in Wonju, Gangwon by comparing the data before and after a rainy season. It selected a closed-type erosion control dam (boulder stone), an open-type erosion control dam (buttress), and a control area and surveyed two upstream points and two downstream points four times between March and September 2019. The flow velocity mostly increased in the closed-type, open-type, and control areas but decreased in St. 3 after the rainy season. The number of benthic macroinvertebrates species and their populations mostly decreased after the rainy season, and the rate of decrease in the populations in the open-type and control areas were more similar than the closed-type area. Species and populations of the EPT groups mostly decreased after the rainy season. A result of the similarity analysis showed that the closed-type and open-type areas were separated by 38.4% with the control area before the rainy season, but the open-type and control areas were separated by 51.3% with the closed-type area after the rainy season. A result of the principal components analysis (PCA) based on axis 1 showed that the closed-type area had a positive value before and after the rainy season, and the open-type and control areas had a negative value before and after the rainy season. The open-type area was more correlated with the control area than the close type. The analysis of the EPT groups showed the distribution of Ephemeroptera in the closed-type area and Trichoptera in the open-type and control areas. The result of this study shows that the installation of erosion control dam can cause changes in benthic macroinvertebrates community and that the open-type area had a smaller difference community difference from the control area after the rainy season than the closed-type area.

Rheological Characteristics of Hydrogen Fermented Food Waste and Review on the Agitation Intensity (음식물류폐기물 수소 발효액의 유변학적 특성과 교반강도 고찰)

  • Kim, Min-Gyun;Lee, Mo-Kwon;Im, Seong-Won;Shin, Sang-Ryong;Kim, Dong-Hoon
    • Journal of the Korea Organic Resources Recycling Association
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    • v.25 no.4
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    • pp.41-50
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    • 2017
  • The design of proper agitation system is requisite in biological waste treatment and energy generation plant, which is affected by viscosity, impeller types, and power consumption. In the present work, hydrogen fermentation of food waste was conducted at various operational pHs (4.5~6.5) and substrate concentrations (10~50 g Carbo. COD/L), and the viscosity of fermented broth was analyzed. The $H_2$ yield significantly varied from 0.51 to $1.77mol\;H_2/mol\;hexose_{added}$ depending on the pH value, where the highest performance was achieved at pH 5.5. The viscosity gradually dropped with shear rate increase, indicating a shear thinning property. With the disintegration of carbohydrate, the viscosity dropped after fermentation, but it did not change depending on the operational pH. At the same pH level, the $H_2$ yield was not affected much, ranging $1.40{\sim}1.86mol\;H_2/mol\;hexose_{added}$ at 10~50 g Carbo. COD/L. The zero viscosity and infinite viscosity of fermented broth increased with substrate concentrations, from 10.4 to $346.2mPa{\cdot}s$, and from 1.7 to $5.3mPa{\cdot}s$, respectively. There was little difference in the viscosity value of fermented broth at 10 and 20 g Carbo. COD/L. As a result of designing the agitation intensity based on the experimental results, it is expected that the agitation intensity can be reduced during hydrogen fermentation. The initial and final agitation intensity of 30 g Carbo. COD/L in hydrogen fermentation were 26.0 and 10.0 rpm, respectively. As fermentation went on, the viscosity gradually decreased, indicating that the power consumption for agitation of food waste can be reduced.

New Methods for Separation of Crude Ginseng Saponins (인삼 조사포닌의 새로운 분리 방법)

  • Shin, Ji-Young;Choi, Eon-Ho;Wee, Jae-Joon
    • Korean Journal of Food Science and Technology
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    • v.33 no.2
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    • pp.166-172
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    • 2001
  • In order to increase ginsenoside content, to reduce chemical change, to shorten extracting procedure, new methods of extraction and fractionation of crude ginseng saponin were established and compared for their chemical composition. Those are hot MeOH extraction/n-BuOH fractionation (BuOH method) and hot MeOH extraction/Diaion HP-20 adsorption/MeOH elution (HP-20 method), which are already known methods, and additional three new methods: hot MeOH extraction/cation AG 50W $adsorption/H_2O$ elution/n-BuOH extraction (AG 50W method), cool MeOH extraction/Diaion HP-20 adsorption/MeOH elution (cool extraction method) and direct extraction with EtOAc/n-BuOH (direct extraction method). AG 50W method provided a crude saponin showing the highest content of ginsenosides of 61.5% and the lowest contents of protein and free amino acids of 0.93% and 0.19%, respectively. The protein content was the highest as 14.18% in the crude saponin by HP-20 method, while free sugar content was the highest as 13.5% by BuOH method, indicating that these are factors that lower the rate of ginsenoside in crude saponins by those methods. On the other hand, it was revealed that AG 50W method produced large amount of prosapogenins during the pass through the cation exchange resin (AG 50W) column being strongly acidic. Crude saponin from direct extraction method showed relatively higher composition of ginsenoside $Rg_1$ and Re. The results suggest that contents and composition of ginsenosides and other chemical components in crude ginseng saponin greatly depend on the condition of the extraction and fractionation.

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Effect of Hormones and Short Chain Fatty Acids on CYP7A1 Gene Expression in HepG2 Cell (호르몬과 단쇄지방산이 HepG2 Cell 내에서 CYP7A1 발현에 미치는 효과)

  • Yang, Jeong-Lye;Lee, Hyun-Jung;Kim, Yang-Ha
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.5
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    • pp.573-580
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    • 2005
  • Cholesterol $7\alpha-hydroxylase$ (CYP7A1) is the rate-limiting enzyme in the conversion of cholesterol to bile acids and plays a central role in regulating cholesterol homeostasis. We previously showed that a fermentable $\beta-glucan$ ingestion decreased plasma cholesterol levels due to fecal bile acid excretion elevation involved inincrease of cholesterol $7\alpha-hydroxylase$ mRNA expression and activity. It is proposed that short chain fatty acids (SCFA) produced by cecal and colonic fermentation of soluble fiber are associated with cholesterol-lowering effect of fiber. In the present study, we investigated whether CYP7A1 expression is up-regulated by short chain fatty acids or by hormones in cultured human hepatoma (HepG2) cells. Confluent HepG2 cell were incubated with acetate, propionate, or butyrate at 1 mM concentration for 24 hrs. Acetate as well as propionate increased to 1.8-fold expression of CYP7A1 mRNA than the control. Butyrate also increased 1.5-fold expression of CYP7A1 mRNA. Our data show for the first time that SCFA increase expression of CYP7A1 mRNA. Adding insulin, dexamethasone and triiodothyronine $(1\;{\mu}M)$ to HepG2 cell increased the expression of CYP7A1 mRNA to $150\%,\;173\%,\;141\%$, respectively. These results suggest that SCFA produced by cecal fermentation stimulate enteric nervous system, in which secreted some neuropeptides may be responsible for change in cholesterol and bile acid metabolism. These findings suggest that SCFA are involved in lowering plasma cholesterol levels due to the up-regulation of CYP7A1 and bile acid synthesis.

Characterization and Functional Analysis of Obox4 during Oocyte Maturation by RNA Interference (생쥐의 난소와 난자에서의 Obox4의 동정과 RNAi를 이용한 기능연구)

  • Lee, Hyun-Seo;Lee, Kyung-Ah
    • Clinical and Experimental Reproductive Medicine
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    • v.34 no.4
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    • pp.293-303
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    • 2007
  • Objective: Previously, we identified differentially expressed genes between GV and MII stage mouse oocytes using ACP technology. When we study one of GV selective genes, Obox family, we found Obox4 mRNA expression in ovaries that has been reported as expressed exclusively in testis. Therefore, this study was conducted for characterization and functional analysis for Obox4. Methods: Expression of Obox4 mRNA was examined in gonads and oocytes by RT-PCR. To determine the role of Obox4 in oocyte maturation, Obox4 dsRNA was microinjected into the cytoplasm of GV oocytes followed by 16 h of incubation in the plain medium or by 24 h of incubation in the medium containing IBMX. After RNAi, phenotypes and maturation rates were observed, change in mRNA expression was evaluated, and chromosomal status was confirmed by orcein staining. Results: Obox4 has minimal expression in the ovary compared to that of the other family members. When oocytes were cultured for 16 h in M16 medium after RNAi, maturation rate was not changed significantly, compared with that of non-injected or buffer-injected control oocytes. Surprisingly, however, when oocytes were cultured for 24 h in M16 containing IBMX, in which oocytes were supposed to arrest at GV stage, Obox4 RNAi oocytes were advanced to MI and MII. Spindle structure was disappeared and the chromosomes were condensed in the oocytes after Obox4 RNAi. Conclusions: This is the first report on the expression of Obox4 in the ovary and oocytes. Results of the study suggest that Obox4 plays a crucial role in spindle formation and chromosome segregation during meiosis in oocytes. In addition, Obox4 may play an important role in cAMP-dependent signal cascades of GV-arrest in mouse oocytes.

A Clinical Study on Allergic rhinitis (알레르기 鼻炎의 臨床的 硏究)

  • Cho Soo-hyun;Jee Seon-young
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.14 no.2
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    • pp.173-182
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    • 2001
  • This Study is attempted in order to observe a clinical analysis from Constitution medical view point about allergic rhinitis. We studied 71 patients who had visited Dept. surgery, opthalmology & otolaryngology, col1ege of Oriental Medicine, Kyungsan University, Pohang, Korea and were treated by medications of Sasang Constitution and Constitution-Acupunture with allergic rhinitis from March 1, 2000 to February 28, 2001. The results were as follows: 1. The sex distribution was 71 males($69\%$), 22 femail($31\%$), In age distribution, the average was 29.6. The peak age was thirties($36.7\%$), teen-ager was $23.9\%,\;fortieth\;was\;15.5\%,\;under\;10\;years\;old\;was\;9.9\%,\;twenties\;was\;7\%,\;fifties\;was\;5.6\%,\;sixtisth\;was\;1.41\%$. 2. In the age of onset, thirties was $29.6\%$, teen-ager was $19.7\%$, twenties was $18.3\%$, under 10 years old and fortieth was $14.1\%$, fifties was $3.8\%$, sixtisth was $1.41\%$. 3 In monthly distribution. september was $25.8\%$, january was $14.1\%$, october was $11.3\%$. november and august was $8.5\%$, april was $7\%$, febuary and may were $5.6\%$, june, july. December were each $4.2\%$, In the distribution of season. the peak season was fall from september to November. 4. In the duration of the disease, 1-3 years was $26.8\%$, 3-5 years was $19.7\%$, 6 months - 1 year $16.9\%$, 5-10 years was $14.1\%$, under 6 months was $11.3\%$, over 10years and over 15 years were each $5.6\%$. 5. In the three main symptom, hydrorrhoea was $71.8\%$, nasal obstruction was $67.6\%$, sneezing was $64.8\%$. In others, fatique was $25.6\%$, headache was $14.1\%$, itching and cough was $11.3\%$, laryngopharyngeal discomfort and red eye were $4.2\%,\;infirmity\;was\;2.8\%$. 6. Patients whose families have allergic disease account for 26 cases($36.6\%$). 7. There was no past history in 37 cases($52.l\%$). In past history distribution, digestive tract disease was $12.7\%$, paranasal sinusitis was $8.5\%$, allergic dermatitis was $7\%$, common cold was $4.2\%$. otitis media, bronchitis, asthma, tonsillitis were $2.8\%$. 8. Sasang Constitution classification was Soyanggin in 52 cases($73.2\%$), Taeumgin in 12 cases($16.9\%$). Soumgin in 7 cases($9.9\%$). 9. In the duration of treatment, it was 1-2 weeks in 26 cases($36.6\%$), 2-4 weeks was $21.1\%$, under 1weeks was $14.1\%$, 4-6 weeks was $11.3\%$, 6-8 weeks was $8.5\%$, 8-10 weeks was $5.6\%$, over 10 weeks was $2.8\%$. 10. We had a follow-up survey the effect of treatment in the 60 cases. there was fair in 25 cases($41.7\%$), good in 21cases($35\%$), excellent in 3cases($5\%$)로 total rate of treatment was $81.7\%$. The case of no change was $16.7\%$, the case of poor was $1.6\%$.

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Soil Chemical Property, Mortality Rates and Growth of Planting Trees from Soil Covering Depths in Coastal Reclaimed Land of Asan Area (아산지역 해안매립지의 복토높이에 따른 토양화학성, 수목 고사율 및 생장 특성)

  • Byun, Jae-Kyeong;Kim, Choon-Sig;Lim, Chae-Cheol;Jeong, Jin-Hyon
    • Korean Journal of Soil Science and Fertilizer
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    • v.44 no.3
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    • pp.502-509
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    • 2011
  • It is important to determine optimum soil covering depths for tree survival and growth because soil covering depths for establishing tree planting bases in coastal reclaimed lands are related to the costs for soil collection, transportation and land reclamation. The objectives of this study were carried out to determine optimum soil covering depths for the normal growth of planted trees in a coastal reclaimed land. The study sites were located in Asan National Industrial Complex in Pyeongtaek City, Gyeonggi-do. Four tree species (Pinus thunbergii, Chamaecyparis pisifera, Zelkova serrata, Quercus acutissima) with one hundred eighty trees of each species were planted in various depths of soil covering (no soil covering, 0.5 m, 1.5 m, 2.0 m soil covering treatments) on April 1998, and the tree growth patterns were measured on September 2000. The change of soil properties, tree mortality rate, root collar diameter and height growth were measured from each soil covering depth treatment on September 2000. Soil pH, EC, exchangeable cations ($K^+$, $Na^+$, $Ca^{2+}$, $Mg^{2+}$), anion $Cl^-$, and base saturation increased with decreased soil covering depths. The mortality rates of tree species showed decreased with increased soil covering depths. The height growth of tree species increased with increased soil covering depths. Height growth of Pinus thunbergii was significantly different between the soil covering depth below 0.5m and other three covering depths, while the growth of other species (C. pisifera, Z. serrata, Q. acutissima) was significantly higher in soil covering depths below 1.5 m than in other soil covering depth treatments. The root collar diameter growth of all tree species showed increasing trends with increased soil covering depths. It is recommended to cover the soil depths above 1.5 m to decrease mortality and to stimulate the tree growth of C. pisifera, Z. serrata and Q. acutissima, while P. thunbergii which is a salt tolerate species could be planted in the 1.0 m soil covering depth.