• Journal of Food Hygiene and Safety
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• v.36 no.6
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• pp.528-536
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• 2021

The purpose of the study was to investigate the content of sinigrin, an index component, in Brassica juncea extract and to evaluate the differentiation of lipocytes, inhibition of production of reactive oxygen species (ROS) and reduction of protein production by lipogenic factors (PPARγ, C/EBPα, aP2) in the processing of Brassica juncea extract and sinigrin in 3T3-L1 preadipocytes which induces Bisphenol A (BPA), an endocrine disrupting environmental hormone. From the investigation, the content of sinigrin in Brassica juncea extract, measured by HPLC, is found to be 21.27±0.2 mg/g. The XTT assay result on BPA-derived 3T3-L1 adipocytes shows there is no cytotoxicity found from 180 µM of sinigrin and 300 ㎍/mL of Brassica juncea extract. Moreover, both intracellular lipid accumulation and ROS production during differentiation of lipocyte are significantly reduced in cells processed with Brassica juncea extract and sinigrin. Lastly, it was also found that the production of transcription factors of lipocyte differentiation, PPARγ, C/EBPα and aP2, were found to be suppressed by the application of Brassica juncea extract and sinigrin. Such results reveals that Brassica juncea is effective in not only suppressing lipid accumulation in the environmental hormone bisphenol A-derived lipocyte, but also in reducing the ROS. The sinigrin-containing Brassica juncea is highly expected to be used in natural functional supplements that prevents the lipid metabolism disorders caused by BPA. There are necessities for additional clinical research and follow-up studies on the in vivo model to verify the relevant mechanisms.

• Journal of Life Science
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• v.32 no.12
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• pp.979-988
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• 2022

Halophytes have been reported to possess a variety of physiological activities, such as anti-cancer, anti-oxidant, anti-diabetes, anti-inflammatory, and anti-obesity. Studies on the roots of the halophyte Rosa rugosa, in particular, have shown a variety of physiological activities and are known to be effective for nursing diabetic complications in traditional Korean medicine. In this study, the effect of R. rugosa on adipogenesis was investigated in 3T3-L1 pre-adipocytes treated with crude extract and solvent fractions (H₂O, n-BuOH, 85% aq. MeOH, and n-Hex) obtained from R. rugosa roots. Treatment with extract and the solvent fractions inhibited the formation of intracellular lipid droplets in differentiated 3T3-L1 adipocytes compared to the untreated group. In particular, n-BuOH and 85% aq. MeOH fractions effectively decreased the expression of adipogenic transcription factors: peroxisome proliferator activated receptor-γ (PPARγ), CCAAT/enhancer-binding protein α (C/EBPα), and sterol regulatory element-binding protein 1c (SREBP1c) in both mRNA and protein levels. In conclusion, these results suggest that R. rugosa contains anti-adipogenic molecules that can be utilized as a nutraceutical against obesity. Further refining of n-BuOH and 85% aq. MeOH fractions and analysis of their action mechanisms could yield potential therapeutic agents with anti-adipogenic effects.

• Journal of Mushroom
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• v.21 no.3
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• pp.132-139
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• 2023

Light plays an important role in fruit-body development and morphology during Pleurotus spp. cultivation. To understand the effects of light color on fruit-body properties, we evaluated the fruit-body characteristics of Pleurotus spp. Varieties cultivated under blue, red, and purple LED light sources. The main results are as follows: The overall fruit-body shape showed differences depending on the color of the LED light. The fruit-bodies of mushroom cultivated under blue and purple light were generally similar to the mushroom shapes typically produced, while those of mushroom cultivated under green light were abnormally shaped, probably due to the absence of effective light source. The average cap lightness of mushrooms cultivated under blue, green, and purple LED lights was 57.0, 57.4, and 59.4, respectively. The average cap lightness of all varieties except Wonhyeong1ho and Hwang-geumsantari cultivated under the three LED light sources were statistically significantly different (P<0.05). The cap redness varied significantly depending on the LED lighting and variety. Only Gonji7hoM, the cap color mutant of Gonji7ho, showed negative cap redness values under all three LED light sources. Among the eight varieties excluding Gonji7ho, the highest cap redness was observed when cultivated under the blue LED. The average harvest weight of the varieties cultivated under purple, blue, and green LED light were 68.0, 58.3, and 50.1 g, respectively. The yield of Gonji7ho, the mushroom variety with the highest yield, cultivated under blue, green, and purple LED light were 92.8, 77.1, and 98.6 g, respectively. The earliness when grown under the purple, blue, and green LED lights were 5.3, 5.8, and 5.8 days, respectively. Among the varieties, six, three, and two cultivars showed the shortest earliness under the purple, green, and blue LED, respectively. The fruit-body lengths were 66.4, 51.8, and 46.8 mm when cultivated under green, purple, and blue lights, respectively. These results are expected to serve as a foundation for producing mushrooms with traits demanded in the market.

• Journal of Dental Rehabilitation and Applied Science
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• v.39 no.1
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• pp.32-44
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• 2023

Purpose: The purpose of this study was to investigate the effect of implant connection type on marginal bone loss (MBL) and to analyze the factors that affect MBL. This study focuses on single implants planted in the upper and lower first molar area. Materials and Methods: A total of 87 implants from 68 patients were tracked for a period over 5 years. There were 57 external connection type (EC) implants and 30 internal connection type (IC) implants in 38 males and 30 females. The MBL and EA were measured from intraoral radiograph images taken after 5 years at most. Results: Significant difference in MBL between EC and IC type was observed in patients without GBR or diabetes. Patients without GBR exhibited an MBL of -0.065 ± 0.859 mm in EC type and -0.627 ± 0.639 mm in IC type (P = 0.025). Using multiple regression analysis, a statistically significant negative correlation was observed between MBL and conditions including implant-abutment connection type (β = -0.303), diabetes (β = -0.113), emergence angle > 30° (β = -0.234), and age (β = -0.776). Conclusion: Within this results, IC type implants had less MBL than EC type, and implant prosthesis with emergence angle over 30° showed greater MBL. To minimize the MBL of the implant and ensure implant stability, careful consideration should be given to the EA of implant prosthesis and its connection type.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.5A
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• pp.565-575
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• 2009

In recent years, there have been numerous explosion-related accidents due to military and terrorist activities. Such incidents caused not only damages to structures but also human casualties, especially in urban areas. To protect structures and save human lives against explosion accidents, better understanding of the explosion effect on structures is needed. In an explosion, the blast load is applied to concrete structures as an impulsive load of extremely short duration with very high pressure and heat. Generally, concrete is known to have a relatively high blast resistance compared to other construction materials. However, normal strength concrete structures require higher strength to improve their resistance against impact and blast loads. Therefore, a new material with high-energy absorption capacity and high resistance to damage is needed for blast resistance design. Recently, Ultra High Strength Concrete(UHSC) and Reactive Powder Concrete(RPC) have been actively developed to significantly improve concrete strength. UHSC and RPC, can improve concrete strength, reduce member size and weight, and improve workability. High strength concrete are used to improve earthquake resistance and increase height and bridge span. Also, UHSC and RPC, can be implemented for blast resistance design of infrastructure susceptible to terror or impact such as 9.11 terror attack. Therefore, in this study, the blast tests are performed to investigate the behavior of UHSC and RPC slabs under blast loading. Blast wave characteristics including incident and reflected pressures as well as maximum and residual displacements and strains in steel and concrete surface are measured. Also, blast damages and failure modes were recorded for each specimen. From these tests, UHSC and RPC have shown to better blast explosions resistance compare to normal strength concrete.

• Journal of the Korean Society of Food Culture
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• v.23 no.1
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• pp.90-96
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• 2008

This study was performed to reveal nutritional excellency of popular Korean dishes, which were intended to distribute as a take-out type food suited for Americans. Four Korean dishes were selected due to their high preference from American sensory panels: Jeyuk-bokkeum (B), Kimchi-bokkeum (C), Dubu-jorim (D) and Namul (E). Nine weeks of the experimental periods were composed of two parts. In phase 1(5 weeks of the first half), high fat diets were fed to all treatments including the control group (A). In phase 2 (4 weeks of the last half), freeze-dried four Korean dishes were fed to the treatments except for the control. There was no significant difference in the final body weights among the groups as well as daily body weight gains and FER. Organ weights of the control group tended to be smaller than those of the treatment groups. For visceral fats, perirenal fat pad (RFP) and epidydimal fat pad (EFP) of the groups C and D were decreased by 20% compared with those of the group A. Total cholesterol level of the group C (94.13 mg/dL) was significantly lower than any other groups (p<0.05), but there was no significant difference in triglyceride(TG) level. HDL-cholesterol level of group B(20.38 mg/dL) was significantly higher than that of group D (17.25 mg/dL), but no significant differences were seen in groups C and E (p<0.05). In LDL-cholesterol level, the highest level was seen in group D, the lowest level in group E (p<0.05). From the findings, Kimchi-bokkeum, Dubu-jorim and Namul were superior to those of the control and jeyukbokkeum in terms of the blood lipid profiles. It might be a good Korean style take-out items suited for the Americans’ taste along with a good nutritional quality in the near future.

• Food Science and Preservation
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• v.31 no.2
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• pp.287-297
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• 2024

It was confirmed that complex fermentation (CF) was more efficient than single-strain fermentations in inducing changes in the contents of phenolic compounds of Maclura tricuspidate and Pyrus Montana Nakai. A mixture of Maclura tricuspidata, Pyrus montana Nakai, Platycodon grandiflorum and Codonopsis lanceolata were fermented in CF using Aspergillus shirousamii (koji), yeast, and lactic acid bacteria (LAB) for 24 days, and the pH, °Brix, total acidity, anti-oxidant activity, polyphenol content, nitric oxide (NO), and Western blotting of inducible nitric oxide synthase (iNOS), cyclo-oxygenase-2 (COX-2), and tumor necrosis factor-𝛼 (TNF-𝛼) of the sample were determined. There was no significant change in pH and total acidity. °Brix significantly decreased from day 6 onwards. HPLC confirmed that the concentrations of chlorogenic acid, 4-hydrobenzoic acid, vanillic acid, and caffeic acid significantly increased from day 18 during the fermentation. Additionally, DPPH, ABTS radical scavenging activity, total phenol, and total flavonoid were confirmed to be increased until 18 days. NO was significantly inhibited from day 6, along with significant inhibition of iNOS, COX-2, and TNF-a. In conclusion, this study confirmed that CF of low-use (or underutilized) wild vegetables enhances phenolic compounds. It effectively suppresses NO, iNOS, COX-2, and TNF-𝛼, markers of inflammation-related pathogenesis. Altogether, our results suggest that CF of the above plants has a potential anti-inflammatory effect.

• Magazine of the Korean Society of Agricultural Engineers
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• v.16 no.1
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• pp.3225-3262
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• 1974

The purposes of this thesis are to clarify experimentally the variation of ground water temperature in tube wells during the irrigation period of paddy rice, and the effect of ground water irrigation on the growth, grain yield and yield components of the rice plant, and, furthermore, when and why the plant is most liable to be damaged by ground water, and also to find out the effective ground water irrigation methods. The results obtained in this experiment are as follows; 1. The temperature of ground water in tube wells varies according to the location, year, and the depth of the well. The average temperatures of ground water in a tubewells, 6.3m, 8.0m deep are $14.5^{\circ}C$ and $13.1^{\circ}C$, respercively, during the irrigation period of paddy rice (From the middle of June to the end of September). In the former the temperature rises continuously from $12.3^{\circ}C$ to 16.4$^{\circ}C$ and in the latter from $12.4^{\circ}C$ to $13.8^{\circ}C$ during the same period. These temperatures are approximately the same value as the estimated temperatures. The temperature difference between the ground water and the surface water is approximately $11^{\circ}C$. 2. The results obtained from the analysis of the water quality of the "Seoho" reservoir and that of water from the tube well show that the pH values of the ground water and the surface water are 6.35 and 6.00, respectively, and inorganic components such as N, PO4, Na, Cl, SiO2 and Ca are contained more in the ground water than in the surface water while K, SO4, Fe and Mg are contained less in the ground water. 3. The response of growth, yield and yield components of paddy rice to ground water irrigation are as follows; (l) Using ground water irrigation during the watered rice nursery period(seeding date: 30 April, 1970), the chracteristics of a young rice plant, such as plant height, number of leaves, and number of tillers are inferior to those of young rice plants irrigated with surface water during the same period. (2) In cases where ground water and surface water are supplied separately by the gravity flow method, it is found that ground water irrigation to the rice plant delays the stage at which there is a maximum increase in the number of tillers by 6 days. (3) At the tillering stage of rice plant just after transplanting, the effect of ground water irrigation on the increase in the number of tillers is better, compared with the method of supplying surface water throughout the whole irrigation period. Conversely, the number of tillers is decreased by ground water irrigation at the reproductive stage. Plant height is extremely restrained by ground water irrigation. (4) Heading date is clearly delayed by the ground water irrigation when it is practised during the growth stages or at the reproductive stage only. (5) The heading date of rice plants is slightly delayed by irrigation with the gravity flow method as compared with the standing water method. (6) The response of yield and of yield components of rice to ground water irrigation are as follows: \circled1 When ground water irrigation is practised during the growth stages and the reproductive stage, the culm length of the rice plant is reduced by 11 percent and 8 percent, respectively, when compared with the surface water irrigation used throughout all the growth stages. \circled2 Panicle length is found to be the longest on the test plot in which ground water irrigation is practised at the tillering stage. A similar tendency as that seen in the culm length is observed on other test plots. \circled3 The number of panicles is found to be the least on the plot in which ground water irrigation is practised by the gravity flow method throughout all the growth stages of the rice plant. No significant difference is found between the other plots. \circled4 The number of spikelets per panicle at the various stages of rice growth at which_ surface or ground water is supplied by gravity flow method are as follows; surface water at all growth stages‥‥‥‥‥ 98.5. Ground water at all growth stages‥‥‥‥‥‥62.2 Ground water at the tillering stage‥‥‥‥‥ 82.6. Ground water at the reproductive stage ‥‥‥‥‥ 74.1. \circled5 Ripening percentage is about 70 percent on the test plot in which ground water irrigation is practised during all the growth stages and at the tillering stage only. However, when ground water irrigation is practised, at the reproductive stage, the ripening percentage is reduced to 50 percent. This means that 20 percent reduction in the ripening percentage by using ground water irrigation at the reproductive stage. \circled6 The weight of 1,000 kernels is found to show a similar tendency as in the case of ripening percentage i. e. the ground water irrigation during all the growth stages and at the reproductive stage results in a decreased weight of the 1,000 kernels. \circled7 The yield of brown rice from the various treatments are as follows; Gravity flow; Surface water at all growth stages‥‥‥‥‥‥514kg/10a. Ground water at all growth stages‥‥‥‥‥‥428kg/10a. Ground water at the reproductive stage‥‥‥‥‥‥430kg/10a. Standing water; Surface water at all growh stages‥‥‥‥‥‥556kg/10a. Ground water at all growth stages‥‥‥‥‥‥441kg/10a. Ground water at the reproductive stage‥‥‥‥‥‥450kg/10a. The above figures show that ground water irrigation by the gravity flow and by the standing water method during all the growth stages resulted in an 18 percent and a 21 percent decrease in the yield of brown rice, respectively, when compared with surface water irrigation. Also ground water irrigation by gravity flow and by standing water resulted in respective decreases in yield of 16 percent and 19 percent, compared with the surface irrigation method. 4. Results obtained from the experiments on the improvement of ground water irrigation efficiency to paddy rice are as follows; (1) When the standing water irrigation with surface water is practised, the daily average water temperature in a paddy field is 25.2$^{\circ}C$, but, when the gravity flow method is practised with the same irrigation water, the daily average water temperature is 24.5$^{\circ}C$. This means that the former is 0.7$^{\circ}C$ higher than the latter. On the other hand, when ground water is used, the daily water temperatures in a paddy field are respectively 21.$0^{\circ}C$ and 19.3$^{\circ}C$ by practising standing water and the gravity flow method. It can be seen that the former is approximately 1.$0^{\circ}C$ higher than the latter. (2) When the non-water-logged cultivation is practised, the yield of brown rice is 516.3kg/10a, while the yield of brown rice from ground water irrigation plot throughout the whole irrigation period and surface water irrigation plot are 446.3kg/10a and 556.4kg/10a, respectivelely. This means that there is no significant difference in yields between surface water irrigation practice and non-water-logged cultivation, and also means that non-water-logged cultivation results in a 12.6 percent increase in yield compared with the yield from the ground water irrigation plot. (3) The black and white coloring on the inside surface of the water warming ponds has no substantial effect on the temperature of the water. The average daily water temperatures of the various water warming ponds, having different depths, are expressed as Y=aX+b, while the daily average water temperatures at various depths in a water warming pond are expressed as Y=a(b)x (where Y: the daily average water temperature, a,b: constants depending on the type of water warming pond, X; water depth). As the depth of water warning pond is increased, the diurnal difference of the highest and the lowest water temperature is decreased, and also, the time at which the highest water temperature occurs, is delayed. (4) The degree of warming by using a polyethylene tube, 100m in length and 10cm in diameter, is 4~9$^{\circ}C$. Heat exchange rate of a polyethylene tube is 1.5 times higher than that or a water warming channel. The following equation expresses the water warming mechanism of a polyethylene tube where distance from the tube inlet, time in day and several climatic factors are given: {{{{ theta omega (dwt)= { a}_{0 } (1-e- { x} over { PHI v })+ { 2} atop { SUM from { { n}=1} { { a}_{n } } over { SQRT { 1+ {( n omega PHI) }^{2 } } } } LEFT { sin(n omega t+ { b}_{n }+ { tan}^{-1 }n omega PHI )-e- { x} over { PHI v }sin(n omega LEFT ( t- { x} over {v } RIGHT ) + { b}_{n }+ { tan}^{-1 }n omega PHI ) RIGHT } +e- { x} over { PHI v } theta i}}}}{{{{ { theta }_{$\infty$ }(t)= { { alpha theta }_{a }+ { theta }_{ w'} +(S- { B}_{s } ) { U}_{w } } over { beta } , PHI = { { cpDU}_{ omega } } over {4 beta } }}}} where $\theta$$\omega$; discharged water temperature($^{\circ}C$) $\theta$a; air temperature ($^{\circ}C$) $\theta$$\omega$';ponded water temperature($^{\circ}C$) s ; net solar radiation(ly/min) t ; time(tadian) x; tube length(cm) D; diameter(cm) ao,an,bn;constants determined from $\theta$$\omega$(t) varitation. cp; heat capacity of water(cal/$^{\circ}C$ ㎥) U,Ua; overall heat transfer coefficient(cal/$^{\circ}C$ $\textrm{cm}^2$ min-1) $\omega$;1 velocity of water in a polyethylene tube(cm/min) Bs ; heat exchange rate between water and soil(ly/min)

• Tuberculosis and Respiratory Diseases
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• v.44 no.5
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• pp.1094-1104
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• 1997

Background : Spontaneous pneumothoraces(SP) are divided into primary spontaneous pneumothoraces (PSP) which develop in healthy individuals without underlying pulmonary disorders and secondary spontaneous pneumothoraces(SSP) which occur in those who have underlying disorders such as tuberculosis or chronic obstructive lung diseases. Yet there is no established standard therapeutic approach to this disorder, i.e., from the spectrum of noninvasive treatment such as clinical observation with or without oxygen therapy, to aggressively invasive thoracoscopic bullectomy or open thoracotomy. Although chest tube thoracostomy has been most widely used, the patients should overcome pain in the initiation of tube insertion or during indwelling it potential infection and subcutaneous emphysema. Thus smaller-caliber tube has been challenged for the treatment of pneumothorax. Previously, we studied the therapeutic efficacy of 8 French catheter for spontaneous pneumothorax. But there has been few data for effectiveness of small-caliber catheterization in comparison with that of chest tube. In this study, we intended to observe the long-term effectiveness of 8 French catheter for the treatment of spontaneous pneumothoraces in comparison with that of chest tube thoracostomy. Method : From January, 1990 to January, 1996, sixty two patients with spontaneous pneumothoraces treated at Chung-Ang University Hospital were reviewed retrospectively. The patients were sub-divided into a group treated with 8 French catheter(n=23) and the other one with chest tube insertion(n=39). The clinical data were reviewed(age, sex, underlying pulmonary disorders, past history of pneumothorax, size of pneumothorax, follow-up period). And therapeutic effect of two groups was compared by treatment duration(duration of indwelling catheter or tube), treatment-associated complications and recurrence rate. Results : The follow-up period(median) of 8 French catheter group and chest tube group was 28 and 22 months, which had no statistical significance. Ther was no statistically significant difference of clinical characteristics between two groups with SP, PSP, SSP. The indwelling time of 8 French catheter group was $6.2{\pm}3.8$ days, which was significantly shorter than that of chest tube group in SP, $9.1{\pm}7.5$ days(p=0.047). In comparison of treatment-related complication in PSP, 8 French catheter group as 6.25% of complication showed lower tendency than the other group as 23.8% (p=0.041 ; one-tailed, p=0.053; two-tailed). The recurrence rate in each group of SP was 17.4%, 10.3%, which did not show any statistically significant difference. Conclusion : Treatment with 8 French catheter resulted in shorter indwelling time in sponteous pneumothorax, and lower incidence of treatment-related complication in primary spontaneous pneumothorax. And the recurrence rate in each of treatment group showed no statistically significant difference. So, we can recommend the 8 French small-caliber catheter for the initial therapy for spontaneous pneumothorax for the replacement of conventional chest tube thoracostomy. But further prospective study with more subjects of spontaneous pneumothorax will be needed for the evaluation of effectiveness of 8 French cateter.

• Tuberculosis and Respiratory Diseases
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• v.49 no.3
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• pp.332-342
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• 2000

Background : The importance of pro-inflammatory cytokines, especially tumor necrosis factor $\alpha$ (INF-$\alpha$) and interleukin-1$\beta$ (IL-1$\beta$), have been extensively documented in the generation of inflammatory lung disease. Lung epithelial cells are also actively involved in initiating and maintaining inflammation by producing pro-inflammatory mediators. Understanding the mechanism of pro-inflammatory cytokine expression in lung epithelial cells is crucial to the development of new therapeutic modalities for inflammatory lung disease. Transcription of most pro-inflammatory cytokines is dependent on the activation of NF-${\kappa}B$. However, the relationship between pro-inflammatory cytokine expression and NF-${\kappa}B/I{\kappa}B$ pathway in lung epithelial cells is not clear. Methods : BEAS-2B, A549, Na-H157, NCI-H719 cells were stimulated with IL-$1{\beta}$ or TNF-$\alpha$ at various times, and then IL-8 and TNF-$\alpha$mRNA expressions were assayed by Northern blot analysis. IL-$1{\beta}$ or TNF-$\alpha$-induced NF-${\kappa}B$ activation was assessed by the nuclear translocation of p65 NF-${\kappa}B$ subunit. The degradation of $I{\kappa}B{\alpha}$ and $I{\kappa}B{\beta}$ by IL-$1{\beta}$ or TNF-$\alpha$stimulation was assayed by Western blot analysis. The phosphorylation of $I{\kappa}B{\alpha}$ was evaluated by Western blot analysis after pre-treating cells with proteasome inhibitor followed by IL-$1{\beta}$ or TNF-$\alpha$ stimulation. The basal level of IKK $\alpha$ expression was evaluated by Western blot analysis. Results: $I{\kappa}B{\alpha}$ and $I{\kappa}B{\alpha}$ was rapidly degraded after 5 minutes of incubation with IL-$1{\beta}$ or TNF-$\alpha$ in BEAS-2B, A549, and NCI-H157 cells. The activation of NF-${\kappa}B{\alpha}$ and the induction of IL-8 and TNF-$\alpha$ mRNA expression were observed by IL-$1{\beta}$ or TNF-$\alpha$ stimulation in these cells. In contrast, neither the changes in NF-${\kappa}B/I{\kappa}B$ pathway nor IL-8 and TNF-$\alpha$mRNA expression was induced by IL-$1{\beta}$ or TNF-$\alpha$ stimulation in NCI-H719 cells. IL-$1{\beta}$ and TNF-$\alpha$-induced $I{\kappa}B$ phosphorylation was observed in BEAS-2B, A549, and NCI-H157 cells, but not in NCI-H719 cells. The basal level of IKK$\alpha$ expression was not different between cell. Conclusion : NF-${\kappa}B/I{\kappa}B$ pathway plays an important role in the expression of pro-inflammatory cytokine in most lung epithelial cells. The absence of the effect on NF-${\kappa}B/I{\kappa}B$ pathway in NCI-H719 cells sæms to be due to the defect in the intracellular signal transduction pathway upstream to IKK.