• Korean journal of applied entomology
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• v.48 no.2
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• pp.123-158
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• 2009

An attempt was made to stimulate future research by providing exemplary information, which would integrate published knowledge to solve specific pest problem caused by resistance. This review was directed to find a way for delaying resistance development with consideration of chemical(s) nature, of mixture, rotation, or mosaics, and of insecticide(s) compatible with the biological agents in integrated pest management (IPM). The application frequency, related to the resistance development, was influenced by insecticide activity from potentiation, residual period, and the vulnerability to resistance development of chemical, with secondary pest. Chemical affected feeding, locomotion, flight, mating, and predator avoidance. Insecticides with negative cross-resistance by the difference of target sites and mode of action would be adapted to mixture, rotation and mosaic. Mixtures for delaying resistance depend on each component killing very high percentage of the insects, considering allele dominance, cross-resistance, and immigration and fitness disadvantage. Potential disadvantages associated with mixtures include disruption of biological control, resistance in secondary pests, selecting very resistant population, and extending cross-resistance range. The rotation would use insecticides in high and low doses, or with different metabolic mechanisms. Mosaic apply insecticides to the different sectors of a grid for highly mobile insects, spray unrelated insecticides to sedentary aphids in different areas, or mix plots of insecticide-treated and untreated rows. On the evolution of pest resistance, selectivity and resistance of parasitoids and predator decreased the number of generations in which pesticide treatment is required and they could be complementary to refuges from pesticides To enhance the viability of parasitoids, the terms on the insecticides selectivity and factors affecting to the selectivity in field were examined. For establishment of resistant parasitoid, migration, survivorship, refuge, alternative pesticides were considered. To use parasitoids under the pressure of pesticides, resistant or tolerant parasitoids were tested, collected, and/or selected. A parasitoid parasitized more successfully in the susceptible host than the resistant. Factors affecting to selective toxicity of predator are mixing mineral oil, application method, insecticide contaminated prey, trait of individual insecticide, sub-lethal doses, and the developmental stage of predators. To improve the predator/prey ratio in field, application time, method, and formulation of pesticide, reducing dose rate, using mulches and weeds, multicropping and managing of surroundings are suggested. Plant resistance, predator activity, selective insect growth regulator, and alternative prey positively contributed to the increase of the ratio. Using selective insecticides or insecticide resistant predator controlled its phytophagous prey mites, kept them below an economic level, increased yield, and reduced the spray number and fruits damaged.

• Tuberculosis and Respiratory Diseases
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• v.52 no.3
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• pp.219-229
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• 2002

Background : Sepsis-induced acute lung injury (ALI) is caused by many cellular and humoral mediators induced by an endotoxin. Histamine, which is widely distributed in the lungs and has been considered as an important mediator of sepsis. It increases P-selectin expression on the endothelial cell surfaces and induces IL-8 secretion. Therefore, an endotoxin-induced histamine may be related to neutrophil-mediated ALI by inducing the migration and activation of neutrophils in the lung tissue. However, the role of endogenous histamine in endotoxin ALI has not been clarified. The purpose of this study was to investigate how endotoxin-induced ALI is influenced by endogenous histamine and to identify the possible mechanism of action. Materials and Methods : The study consisted of 4 groups using Sprague-Dawley rats : 1) control group, where the rats were infused intratracheally by normal saline, 2) an endotoxin group, where lipopolysaccharide (LPS) was administered intratracheally 3) the $H_2$ receptor antagonist-treated group ($H_2$ group) and 4) the $H_1$ receptor antagonist-treated group ($H_1$ group), where $H_2$-receptor blocker (ranitidine) and $H_1$-receptor blocker(pyrilamine) were co-treated intravenously with the intratracheal administration of an endotoxin. The lung leak index using $I^{125}$-BSA, the total protein and LDH concentration in the lung lavage fluid, myeloperoxidase(MPO) activity in the lung tissue, the pathologic score and the total number of neutrophils, TNF-$\alpha$, IL-$1{\beta}$ and IL-10 in lung lavage (BAL) fluid were measured in each group as the indices of lung injury. Results : Compared to the control group, the endotoxin group exhibited significant increases in all lung injury indices. Significant reductions in the endotoxin-mediated increases in lung leak index (p<0.05) were observed in both the $H_1$ and $H_2$ groups. In addition the total protein (p<0.05) and LDH concentration (p<0.05) in the BAL fluid were also lower in the $H_2$ group compared to the endotoxin group. However, there was no change in the MPO activity in the lung tissue, the pathologic score and the total number of neutrophils in the BAL fluid in both the $H_2$ and $H_1$ groups compared to the endotoxin group. The increases in TNF-$\alpha$ IL-$1{\beta}$ and IL-10 concentrations in the BAL fluid observed in the endotoxin group were not reduced in the $H_2$ and $H_1$ groups. Conclusion : Antihistamine attenuated the enhanced alveolar-capillary permeability induced by the endotoxin via the $H_2$ receptor. However the attenuating mechanism may not be related to the pathogenesis of neutrophil dependent lung injury.

• Tuberculosis and Respiratory Diseases
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• v.44 no.6
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• pp.1256-1262
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• 1997

Background : Leukocyte-endothelial adhesion molecules have been implicated in the pathogenesis of inflammatory disease. ICAM-1, VCAM-1 and E-selectin are cell surface adhesion molecule on vascular endothelial cells. They are up-regulated by inflammatory cytokines and regulate the adhesion and migration of leukocytes across the endothelium. Tuberculosis, a granulomatous disorder is an infection caused by Mycobacterium tuberculosis. The clinical manifestations of tuberculosis are dependent on the cellular immune response to tubercule bacilli. Circulating adhesion molecules are probably formed by cleavage and release into the circulation of the extracellular domain of the membrane bound form. The elevated levels of circulating adhesion molecules have been reported in numerous disease state. To evaluate their role as markers of disease activity in tuberculosis, we measured a sE-selectin, sVCAM-1 and sICAM-1 levels in the serum with severities of mild, moderate and far advanced pulmonary tuberculosis. Methods : The control and test groups were divided as follows. Group I : control(n=5), Group II : patients with mild pulmonary tuberculosis(n=12), Group III : pateints with moderate pulmonary tuberculosis(n=20), Group IV : patients with far advanced pulmonary tuberculosis(n=19). Serum sICAM-1, sVCAM-1 and sE-selectin were measured by ELISA kit Results : Serum soluble adhesion molecules are elevated in patients with pulmonary tuberculosis, Circulating ICAM-1 levels were significantly elevated in patients with moderate and far advanced pulmonary tuberculosis when compared with control group. When compared with control group, serum sVCAM-1 levels showed significant elevation in patients with mild, moderate and far advanced pulmonary tuberculosis. Serum sE-selectin levels were significantly elevated in patients with far advanced pulmonary tuberculosis when compared with control group. Conclusion : These results suggest that sICAM-1, sVCAM-1, and sE-selectin may be invloved in the pathogenesis of tuberculosis. And, particularly, sICAM-1 and sVCAM-1 may be useful markers of the disease activity.

• Journal of Periodontal and Implant Science
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• v.33 no.3
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• pp.457-474
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• 2003

The ultimate objective of periodontal treatment is to get rid of an on-going periodontal disease and further regenerate the supporting tissue, which is already destroyed, functionally. Currently, the bone grafting operation using various kinds of bone grafting materials and the operation for induced regeneration of periodontal tissue using the blocking membrane are performed for regeneration of the destroyed periodontal tissue. However, there are respective limitations Galenical preparations, which are used for regeneration of periodontal of tissue, has less risk of rejective reaction or toxicity that may be incidental to degradation and their effect is sustainable. Thus, in case they are applicable to a clinic, they can he used economically. Chitosan has such compatibility, biological actions including antibacterial activity, acceleration of wound treatment, etc., and excellent mechanical characteristics, which has recently aroused more interest in it. Also, it has been reported that it promotes osteogenesis directly or indirectly by functioning as a matrix to promote migration and differentiation of a specific precussor cell (for example, osteoblast) and further inhibiting the function of such a cell as fibroblast to prevent osteogenesis. In this study, the pure chitosan solution, which was obtained by purifying chitosan, was used. However, since this chitosan is of a liquiform, it is difficult to sustain it in a defective region. It is, therefore, essential to use a carrier for delivering chitosan to, and sustaining it gradually in the defective region. In the calvarial defect model of the Sprague-Dawley rat, it is relatively easy to maintain a space. Therefore, in this study, the chitosan solution with which ACS was wetted was grafted onto the defective region, For an experimental model, a calvarial defect of rat m s selected, and a critical size of the defective region was a circular defect with a diameter of 8 mm. A group in which no treatment was conducted for the calvarial defect was set as a negative control group. Another group in which treatment was conducted with ACS only was set as a positive control group (ACS group). And another group in which treatment was conducted was conducted with by grafting the pure chitosan solution onto the defective region through ACS which was wetted with the chitosan solution was set an experimental group (Chitosan/ACS group). Chitosan was applied to the Sprague-Dawley rat's calvarial bone by applying ACS which was wetted with the chitosan solution, and each Sprague-Dawley rat was sacrificed respectively 2 weeks and 8 weeks after the operation for such application. Then, the treatment results were compared and observed histologically and his tometrically. Thereby, the following conclusions were obtained. 1. In the experimental group, a pattern was shown that from 2 weeks after the operation, vascular proliferation proceeded and osteogenesis proceeded through osteoblast infiltration, and at 8 week after the operation, ACS was almost absorbed, the amount of osteogensis was increased and many osteoid tissue layers were observed. 2. At 2 weeks after the operation, each amount of osteogenesis appeared to be 8.70.8 %, 13.62.3 % and 4.80.7 % respectively in the experimental group, the positive control group and the negative control group. Accordingly, it appeared to be higher in the Experimental group and the positive control group than in the negative control group, but there was no significant difference statistically (p<0.01). 3. At 8 weeks after the operation, each amount of osteogenesis appeared to be 62.26.1%, 17.42.5 % and 8.21.4 % respectively in the experimental group, the positive control group and the negative control group. Accordingly, it appeared to be substantially higher in the experimental group than in the positive control group and the negative control group, and there was a significant difference statistically (p<0.01). As a result of conducting the experiment, when ACS was used as a carrier for chitosan, chitosan showed effective osteogenesis in the perforated defective region of the Sprague-Dawley rat's calvarial bone.

• Journal of Life Science
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• v.30 no.10
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• pp.877-885
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• 2020

Lentinuls edodes has been used for traditional food and medicine around Asia, and a variety of biological effects have been reported. In this study, L. edodes water extract (LWE) was investigated for its anti-photodamage effect in HaCaT keratinocytes. To perform the necessary assays, L. edodes was extracted with distilled water for 8 hr at 40℃ in an extract tank. Anti-photodamage activity was assessed using a scratch wound healing assay, cell proliferation, and a reactive oxygen species (ROS) scavenging test and by measuring the mRNA and protein expression levels of matrix metalloproteinases (MMPs) and type I procollagen. MMPs and collagen expression are major markers of UV-induced photodamage in skin. Prior to photodamage analysis, the total polyphenol and β-glucan contents of the LWE were evaluated and found to be 4.64 mg GAE/g DW and 165.96 mg/g, respectively. Treatment with LWE induced cell migration and cell proliferation in UV-irradiated HaCaT cells, and LWE effectively scavenged the ROS induced by H₂O₂ and UVB irradiation in HaCaT cells. UVB irradiation induced ROS generation and led to increased production of MMP-1 and MMP-9 and to decreased collagen production in human keratinocytes. Treatment with LWE upregulated the expression levels of MMP-1, MMP-9, and type I procollagen in UVB-irradiated HaCaT cells. This study suggests that LWE could be used to develop cosmetic materials with anti-photodamage effects.

• The Journal of the Petrological Society of Korea
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• v.7 no.2
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• pp.69-76
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• 1998

$^{40}Ar/^{39}Ar$ analytical data of hornblende and muscovite separates from granitic rocks in southwestern region of Ogcheon belt shows fellowing tectonic implication, $^{40}Ar/^{39}Ar$ data of 5 samples yield apparent age spectra and $^{37}Ar_{ca}/^{39}Ar_k$ and $^{38}Ar_{CI}/^{39}Ar_k$ plateaus for more than 60% of the $^{39}Ar$ release. Except for HN-100, the $^{36}Ar/^{40}Ar$ versus $^{39}Ar/^{40}Ar$ corelalation diagrams indicate the presence of one distint line. Muscovite of sample PKJ-44 yield flate apparent age plateau for > 60% of the $^{39}Ar_k$ release. In the high temperature steps, the $^{37}Ar_{ca}/^{39}Ar_k$ values are irregular with a correlative increase in $^{38}Ar_{CI}/^{39}Ar_k$, suggesting some Ca and CI rich phase, tapped between the silicate sheet is being argon degassed. The $^{40}Ar/^{39}Ar$ total gas age and the high temperature age of HN-100 is 918.2 Ma and 1360 Ma, respectively. The former affectted by recystallized age of Daebo Orogeny, and the latter indicated age of hornblende closure temperature for cooling stage of amphibole xenolith in granite gneiss. Three rock types of Kwangju granites show about 165 Ma hornblende and muscovite ages with some degassed argon at low temperature steps. These ages of 4 samples indicate also recrystallized age by Daebo Orogeny. In $^{40}Ar/^{39}Ar$ mineral age, Rb/Sr whole age and K/Ar mineral age, discordant ages of southwestern region of Ogcheon belt suggesting cooling rates approaching 3~4$^{\circ}C$/m. y. Such slow cooling rates can be produced by uplift rate of 100m/m.y. or slightly slower than isothem-migration rate derived from the hornblende samples. We conclude that the strongest Orogeny and igneous activity of southwestern region of Ogcheon belt are middle proterozoic era (about 1360 Ma) and middle Jurassic period (about 165 Ma).

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.6
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• pp.1134-1141
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• 2002

Adhesion of leukocytes to the activated vascular endothelium and their subsequent recruitment/migration into the artery wall are key features in the pathogenesis of atherosclerosis and inflammatory diseases. These features have been mediated by cell adhesion molecules including vascular cell adhesion molecule-1 (VCAM-1) and in tracellular cell adhesion molecule-1 (ICAM-1). This study examined whether flavonoids inhibit the pro-inflammatory cytokine TNF-$\alpha$-induced monocyte adhesion via a modulation of the protein expression of VCAM-1 and ICAM-1 of human umbilical vein endothelial cells (HUVECs). TNF-$\alpha$ markedly increased the adhesion of THP-1 monocytes to endothelial cells and induced the expression of VCAM-1, ICAM-1 and E-selectin proteins in HUVECs. Micromolar concentrations of the flavones luteolin and apigenin and the flavonol quercetin near completely blocked the monocyte adhesion to the activated endothelial cells and the induction of these adhesion molecules. However, equimicromolar catechins of (-)epigallocatechin gallate and (+)catechin, the flavonol myr- icetin and the flavanones of naringin and hesperidin had no effect on TNF-$\alpha$-activated monocyte adhesion. (-)Epigallocatechin gallate, (+) catechin, and naringin did not attenuate the TNF-$\alpha$ induction of these adhesion molecules. Furthermore, culture with luteolin and apigenin strongly blocked the expression of TNF-$\alpha$-induced VCAM-1 mRNA and modestly attenuated ICAM-1 mRNA. Quercetin modestly decreased the TNF-$\alpha$-activated VCAM-1 and ICAM-1 mRNAs. These results demonstrate that flavonoids classified as flavones and flavonols may inhibit monocyte adhesion to the TNF-$\alpha$-activated endothelium, most likely due to a blockade of expression of functional adhesion molecules down-regulated at the transcriptional level, indicating a definite linkage between the chemical structure of flavonoids and the expression of cell adhesion molecules. Furthermore, the antiathero-genic feature of flavonoids appears to be independent of their antioxidant activity.

• Korea journal of population studies
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• v.16 no.2
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• pp.84-110
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• 1993

This study aims at identifying the recent change in marriage behaviors in Korea. The data used here is the vital statistics compiled from the vital registration system of which registration form is put on one from together with the civil registration form. According to the results of this analysis, since 1970 the number of marriages has steadily increased from about 300, 000 in the former of 1970s to about 400, 000 in the latter of 1980s, appproximately coincided with the change in population size at the marriageable age span. The few exceptions that can be seen in the 1970s seem to result from the impact of social upheavals during 1950s; since the birth cohorts affected by the low fertility during the Korean war and the post-war baby-boom generations chracterized by the high fertility entered the marriage market in the 1970s. However, the marriage rate shows a little increase from around 7 in the former of 1970s to around 9 in the latter of 1980s, indicating that the marriage prevalence has been more or less inconsiderably changed during this period. It is also found that the proportion of remarriage to the total marriages has increased to around 10 per cent in 1989, while decreasing that of first marriage. This fact can be attributable to the higher prevalence of divorces and the collapsing of the Confucianism ethic which contributed to expediting the remarriage of widows. Although this proportion is insignificant compared with that of the of more developed countries, it is not difficult to say that the proportion of remarriages will continue to increase in future. The age first at first marriage(AFM) which directly affects the span exposed to the risks pregnancy has increased to the age about 28 for male and about 25 for female in recent years. However, big difference in AFM between urban and rural areas has narrowed, resultant from the increasing involuntary postponement of marriage of rural young population who have met difficulties in seeking their bride or bridegroom in rural areas characterized by the heavy out-migration of young, particularly female, population. The present study shows the reverse relationship between AFM and educational attainment; i.e, the higher the educational attainment the lower the AFM. The conditions which are taken into considerations were the class and the family in the past time but which are, educational attainment, job and personal characteristics. With regard to the age condition, in recent years the male prefers the female younger than himself on the average by 3 years and vice versa, which is reduced form 4-5 years in beginning of 1970s. The age difference bride and bridegroom tends to decrease with the educational attainment increase. This may be attributable to the fact that the persons with the higher educational attainment prefer the love marriage and hence are more likely to choose their counterparts in the about same age. The education condition is characterized by the bridegroom having the higher educational level than bride. It is also significant to note that the proportion of love marriage has increased, whereas that of traditional arranged marriage has decreased. This is true in the urban areas than the rural areas, indicating that rights as well as responsibilities for marriage have been handed over the young population from their parents. In conclusion, the change in the marriage behaviors in Korea are characterized by increasing tendency for the postponement of first marriage, higher prevalences of divorces and a result remarriages, increase of love marriages, narrowing age difference between bride and bridegroom, etc. which are the main results of rapid industrization, increase in educational and economic activity opportunities and change in the ideals of marriages during the past decades. These phenomena prevailing in Korean society would affect not only the family structure that will become less proliferiated but the population size and structure. The most important is that the changes in marriage behaviors of Koreans and their impact on the society with respect to norms, values, morals, of individual and family in the social aspect, change in population size and structure in the demograpic aspects, and economic development in the economic aspects should be integrated into the plannings towards to the future.

• Journal of Life Science
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• v.25 no.7
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• pp.801-809
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• 2015

Homotypic cell adhesion (homotypic aggregation) in activated monocytes plays a central role in physiological and pathological processes including inflammatory responses, differentiation and migration. The extract of the Prunus mume Sieb. et Zucc. fruit (Maesil) has potential benefits to human health; such as anti-viral, anti-microbial, and anti-cancer activities. Indeed, Maesil extract may modulate inflammatory responses via interference with homotypic aggregation in monocytes. In the present study, the molecular mechanisms underpinning the therapeutic efficacy of Maesil extract in inflammatory diseases were investigated. It was found that Maesil extract inhibited homotypic aggregation in lipopolysaccharide (LPS)-activated monocytes. This was mediated by reduction of nitric oxide (NO) production, partly via inhibition of inducible nitric oxide synthase (iNOS) expression in LPS-activated THP-1 cells. It was confirmed that NO inhibition is a key mechanism in Maesil induced blockade of monocyte aggregation through identification of reversal of this inhibitory effect by the NO-producing agent S-nitroso-N-acetyl penicillamine (SNAP). In addition, Maesil extract significantly attenuated LPS-induced IκB-α phosphorylation and NF-κB translocation into the nucleus. In conclusion, Maesil extract exerts anti-inflammatory effects via inhibition of homotypic aggregation of LPS-activated monocytes through mechanisms involving the suppression of NO production and NF-κB activity, suggesting Maesil extract as a potential therapeutic candidate for the prevention and treatment of chronic inflammatory diseases.

• Economic and Environmental Geology
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• v.56 no.4
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• pp.421-433
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• 2023

The final disposal of spent nuclear fuel(SNF) from nuclear power plants takes place in a deep geological repository. The metal canister encasing the SNF is made of cast iron and copper, and is engineered to effectively isolate radioactive isotopes for a long period of time. The SNF is further shielded by a multi-barrier disposal system comprising both engineering and natural barriers. The deep disposal environment gradually changes to an anaerobic reducing environment. In this environment, sulfide is one of the most probable substances to induce corrosion of copper canister. Stress-corrosion cracking(SCC) triggered by sulfide can carry substantial implications for the integrity of the copper canister, potentially posing a significant threat to the long-term safety of the deep disposal repository. Sulfate can exist in various forms within the deep disposal environment or be introduced from the geosphere. Sulfate has the potential to be transformed into sulfide by sulfate-reducing bacteria(SRB), and this converted sulfide can contribute to the corrosion of the copper canister. Bentonite, which is considered as a potential material for buffering and backfilling, contains oxidized sulfate minerals such as gypsum(CaSO4). If there is sufficient space for microorganisms to thrive in the deep disposal environment and if electron donors such as organic carbon are adequately supplied, sulfate can be converted to sulfide through microbial activity. However, the majority of the sulfides generated in the deep disposal system or introduced from the geosphere will be intercepted by the buffer, with only a small amount reaching the metal canister. Pyrite, one of the potential sulfide minerals present in the deep disposal environment, can generate sulfates during the dissolution process, thereby contributing to the corrosion of the copper canister. However, the quantity of oxidation byproducts from pyrite is anticipated to be minimal due to its extremely low solubility. Moreover, the migration of these oxidized byproducts to the metal canister will be restricted by the low hydraulic conductivity of saturated bentonite. We have comprehensively analyzed and summarized key research cases related to the presence of sulfates, reduction processes, and the formation and behavior characteristics of sulfides and pyrite in the deep disposal environment. Our objective was to gain an understanding of the impact of sulfates and sulfides on the long-term safety of high-level radioactive waste disposal repository.