• Horticultural Science & Technology
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• v.29 no.6
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• pp.555-560
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• 2011

The objective of this study was carried out to investigate the proper plant growth regulator for increasing the number of flower, fruit set, and to enlarge the size of the berries in Ardisia pusilla. Flower bud formation was used rooted cutting, and fruit set, enlargement, and coloration of fruit were used with two years-old. $GA_3$ concentrations were treated with 0, 100, 200, or $400mg{\cdot}L^{-1}$. Flower bud formation was effective in $400mg{\cdot}L^{-1}$ $GA_3$ and it was 1.8 times greater than control. Plant growth regulators were applied by foliar spray at full bloom stage to increase the fruit set. As a result, $GA_3$ was the most effective for increasing fruit set. Also, auxins of 4-CPA (Tomatotone, Donbu hitech Co., Korea) and dichloprop triethanol amine (Antifall, Bayer Crop Science Co., Ltd., Korea) were effective. When $GA_3$ concentrations of 0.5 and $1.0mg{\cdot}L^{-1}$ were used, fruit set (%) reached to 70% and 77%, respectively. Effectiveness of $GA_3$ was 1.8 times greater than control. Also, auxins, dichloprop triethanol amine increased to about 7-12% during fruit setting, but cytokinin and anti-gibberellin were ineffective. To investigate the fruit enlargement and coloration, $GA_3$ was treated with 0.3, 0.6, and $1.2mg{\cdot}L^{-1}$. Fruit enlargement was achieved to about 15% by $GA_3$ $0.6mg{\cdot}L^{-1}$ when $GA_3$ was treated 3 times at the interval of 1 month per treatment when fruit size was about 2-3mm (after full-blooming two months). But anthocyanin contents for coloration of fruit skin were not significant according to $GA_3$ concentration. The results showed that $GA_3$ enhanced bud formation, fruit set and enlargement of fruit size in Ardisia pusilla.

• Korean Journal of Plant Resources
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• v.21 no.2
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• pp.134-138
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• 2008

Nerine from south africa and its sparkling flower shape make us estimate it as a hopeful kind of cut follow. There was a few studies on Nerine in korea. We started this study to set bulb propagation methods. The propagation by tissue culture was changeable according to the growth regulators The best growth regulator combination which makes a lot of Bulblet was NAA $0{\sim}0.5$ + BA $0.5{\sim}2.0mg\;{\cdot}\;L^{-1}$ in Nerine bowdenii ‘Favourite’ and Nerine sarniens ‘Red’ respectively. The adjust culture media source for tissue culture were glucose 9% as a carbon source and ($NH_4+NO_3$) 40mM as a nitrogen source. When glucose was used as a carbon source, Bulblet were harvested a little bit low then sucrose but comparative emergence rate was so high that it is good for carbon source in nerine tissue culture. When we consist culture media as MS+BA $1.0mg\;{\cdot}\;L^{-1}$+sucose 7% + ($NH_4+NO_3$) 40mM, the produced Bulblet were reached up to 1.7 each per bulb and emergence rate was up to 100% irrespective of acclimatization period. The suitable culture explant for nerine tissue culture was scale. When scale was cultured with MS+BA $1.0mg\;{\cdot}\;L^{-1}$+sucose 7%, its propagation efficiency was 54 times greater than using growing point. A proper culture part of the scaly leaf was middle part (8 scaly leaf from outer 8th scaly leaf) when middle part was cultured the number of Bulblet were up to 1.8 each per explant.

• Journal of Bio-Environment Control
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• v.23 no.2
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• pp.77-82
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• 2014

The present study was conducted to establish an effect and a proper concentration for treatment with gibberellic acid ($GA_3$) and thidiazuron (TDZ), resulting with increase berry size and yield in Gaeryangmeoru grapes. Berry size was increased by treatment with $GA_3$, and the fruit clusters obtained for the groups treated with $GA_3$ concentrations of 100 and $200mg{\cdot}L^{-1}$ were bigger. The berry number was also enhanced in $GA_3$ treated groups, but the soluble solid content and acidity was not significantly different. Damage caused by $GA_3$ treatment, such as peel pollination and berry shatter, was observed in the group with $200mg{\cdot}L^{-1}$. The berry size was larger in group treated with a high concentration of $GA_3$ and TDZ respectively than in those treated with low concentrations in the treatment mixed $GA_3$ and TDZ; however, fruit with low soluble solid content and high acidity was harvested after $GA_3$ and TDZ treatment due to delay of berry ripening. The pericarp tissue layers were not changed, but the distance from the epidermis layer to vascular bundle tissue was increased as a result of $GA_3$ and TDZ treatment. Therefore, $GA_3$ and TDZ did not affect an cell division but not cell size, resulting in an enlarged berry size. It is necessary to treat plant growth regulators 2~3 times and immediately after berry set to enhance berry set rate, because the period of berry set is short. This study suggests that the proper concentration for enhancing berry size and set were up to $100mg{\cdot}L^1$ $GA_3$ or $50mg{\cdot}L^{-1}GA_3+1.25mg{\cdot}L^{-1}$ TDZ, and it is necessary to pay attention to harvest mature fruits because of the delay of ripening caused by the usage of TDZ.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.27 no.5
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• pp.373-384
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• 2001

Cellular proliferation is an intricately regulated process mediated by the coordinated interactions of critical growth control genes. Two of these factors in mammalian cells are the p53 and mdm-2 genes. A protein product of the mem-2 oncogene has been recently shown to associate with the protein encoded by the tumor suppressor gene p53. The p53 tumor suppressor protein is stabilized in response to DNA damage and other stress signals and causes the cell to undergo growth arrest or apoptosis, thus preventing the establishment of mutations in future cellular generations. Mutation or loss of p53 is a very common event in tumor progression. It occurs in about 50% of all tumors analysed including of colon, lung, breast and liver. The cellular mdm-2 gene, which has potential transforming activity that can be activated by overexpression, is amplified in a significant percentage of human sarcoma and in other mammalian tumors. Proteins encoded by the mdm-2 gene are able to bind to the p53 protein and, when overexpressed, can inhibit p53's transcriptional activation function, thus mdm-2 can act as a negative regulator of p53 function. Experimental study was performed to observe the relationship between p53 gene mutation and mdm-2 protein expression and apply the results to the clinical activity. 36 golden syrian hamster each weighing $60{\sim}80g$ were used and painted with 0.5% DMBA by 3 times weekly on the right buccal cheek(experimental side) for 6, 8, 10, 12, 14 and 16 weeks. Left buccal cheek(control side) was treated with mineral oil as the same manner to the right side. The hamsters were sacrificed on the 6, 8, 10, 12, 14 & 16 weeks. Normal and tumor tissues from paraffin block were examined for histology and immunohistochemistry observation, and were completely dissected by microdissection and DNA from both tissue were isolated by proteins K/phenol/chloroform extraction. Segments of the hamster p53 exons 5, 6, 7 and 8 were amplified by PCR using the oligonucleotide primers, and then confirmational change was observed by SSCP respectively. The results were as follows : 1. Dysplasia at 6 weeks, carcinoma in situ at 8 weeks and invasive carcinoma from 10 weeks could be observed in experimental groups. 2. p53 mutations were detected in 10 of the 36(28%) and the exons 6(6 of the 10 : 60%) was the most hot spot area among the highy conserved region(exons 5, 6, 7 & 8). 3. Immunohistochemical study confirmed 22 of the 36(61%) of p53 expression involving 10 of p53 mutations. 4. mdm-2 expression of was showed in 3 of the 36(8%) involving 1 of the 22 of p53 expression and 2 of the 14 of p53 non-expression. From the above results, mutation of p53 gene or expression of p53 protein may have the influence of the DMBA induced carcinoma of hamster buccal pouch but the expression of mdm-2 protein may not have relationship with tumorigenesis.

• Journal of Plant Biotechnology
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• v.33 no.3
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• pp.195-207
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• 2006

Stem cells are the primordial, initial cells which usually divide asymmetrically giving rise to on the one hand self-renewals and on the other hand progenitor cells with potential for differentiation. Zygote (fertilized egg), with totipotency, deserves the top-ranking stem cell - he totipotent stem cell (TSC). Both the ICM (inner cell mass) taken from the 6 days-old human blastocyst and ESC (embryonic stem cell) derived from the in vitro cultured ICM have slightly less potency for differentiation than the zygote, and are termed pluripotent stem cells. Stem cells in the tissues and organs of fetus, infant, and adult have highly reduced potency and committed to produce only progenitor cells for particular tissues. These tissue-specific stem cells are called multipotent stem cells. These tissue-specific/committed multipotent stem cells, when placed in altered environment other than their original niche, can yield cells characteristic of the altered environment. These findings are certainly of potential interest from the clinical, therapeutic perspective. The controversial terminology 'somatic stem cell plasticity' coined by the stem cell community seems to have been proved true. Followings are some of the recent knowledges related to the stem cell. Just as the tissues of our body have their own multipotent stem cells, cancerous tumor has undifferentiated cells known as cancer stem cell (CSC). Each time CSC cleaves, it makes two daughter cells with different fate. One is endowed with immortality, the remarkable ability to divide indefinitely, while the other progeny cell divides occasionally but lives forever. In the cancer tumor, CSC is minority being as few as 3-5% of the tumor mass but it is the culprit behind the tumor-malignancy, metastasis, and recurrence of cancer. CSC is like a master print. As long as the original exists, copies can be made and the disease can persist. If the CSC is destroyed, cancer tumor can't grow. In the decades-long cancer therapy, efforts were focused on the reducing of the bulk of cancerous growth. How cancer therapy is changing to destroy the origin of tumor, the CSC. The next generation of treatments should be to recognize and target the root cause of cancerous growth, the CSC, rather than the reducing of the bulk of tumor, Now the strategy is to find a way to identify and isolate the stem cells. The surfaces of normal as well as the cancer stem cells are studded with proteins. In leukaemia stem cell, for example, protein CD 34 is identified. In the new treatment of cancer disease it is needed to look for protein unique to the CSC. Blocking the stem cell's source of nutrients might be another effective strategy. The mystery of sternness of stem cells has begun to be deciphered. ESC can replicate indefinitely and yet retains the potential to turn into any kind of differentiated cells. Polycomb group protein such as Suz 12 repress most of the regulatory genes which, activated, are turned to be developmental genes. These protein molecules keep the ESC in an undifferentiated state. Many of the regulator genes silenced by polycomb proteins are also occupied by such ESC transcription factors as Oct 4, Sox 2, and Nanog. Both polycomb and transcription factor proteins seem to cooperate to keep the ESC in an undifferentiated state, pluripotent, and self-renewable. A normal prion protein (PrP) is found throughout the body from blood to the brain. Prion diseases such as mad cow disease (bovine spongiform encephalopathy) are caused when a normal prion protein misfolds to give rise to PrP$^{SC}$ and assault brain tissue. Why has human body kept such a deadly and enigmatic protein? Although our body has preserved the prion protein, prion diseases are of rare occurrence. Deadly prion diseases have been intensively studied, but normal prion problems are not. Very few facts on the benefit of prion proteins have been known so far. It was found that PrP was hugely expressed on the stem cell surface of bone marrow and on the cells of neural progenitor, PrP seems to have some function in cell maturation and facilitate the division of stem cells and their self-renewal. PrP also might help guide the decision of neural progenitor cell to become a neuron.

• Journal of agriculture & life science
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• v.43 no.2
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• pp.23-30
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• 2009

The object of this study was to evaluate the effect of the gibberellin treatment on fruit enlargement and ripening promotion in 'Niitaka' pear(Pyms pynfolia). Fruit weight was similar between $GA_{4+7}$ treatments and the gibberellin-paste control, but fairly increased of fruit weight compared to non-treatment Most effective time for $GA_{4+7}$ treatment to increase diameter and length was on 35 and 40 days after full bloom, respectively. Shape index was similar in all treatments. Fruit enlargement at the period of early growth, $GA_{4+7}$ 2.4% treatment was remarkably effective than $GA_{3}+GA_{4+7}$ 2.7% treatment or non-treatment However at the period of maturity, $GA_{4+7}$ 2.4% treatment and $GA_{3}+GA_{4+7}$ 2.7% treatment showed little differences in fruit enlargement and coloring. In maturing promotion effect, young fruit treated with $GA_{3}+GA_{4+7}$ showed similar fruit coloring to ethephon treatment on 35 days after full bloom, and both of those treatments promoted fruit coloring than non- treatment about 6 days. $GA_{3}+GA_{4+7}$ treatments resulted higher solid content and decreased acidity than non-treatment However, there was no differences in fruit hardness comparing to non-treatment As a result, gibberellin was most effective in fruit enlargement, so as all $GA_{3}+GA_{4+7}$ treatments were more effective on fruit enlargement than ethephon treatment or non-treatment Specifically, when $GA_{3}+GA_{4+7}$ was treated 35days after full bloom of flower, the diameter, the length and the shape of fruit index were best, and fruit coloring was good as well.

• Horticultural Science & Technology
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• v.34 no.4
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• pp.528-536
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• 2016

This study was conducted to examine the effect of 0.4% of $CaCl_2$, $2H_2O$, $1mg{\cdot}L^{-1}$ of Calmodulin (CaM)-SH, 250-folds of coating agent (WE-36), 1,000-folds of $GA_{4+7}+BA$ and 3 types of paper bagging treatments on russet incidence and fruit quality attributes of 'Gamhong' apple. The pattern of russet occurrence was slightly different for 4 years (from 2012 to 2015) in 'Gamhong' apple. The russet occurrence was lowest in $GA_{4+7}+BA$ treatment at 20 days after full bloom (DAFB), compared with other treatments. The $GA_{4+7}+BA$ treatment increased fruit weight at 20 DAFB, while the other fruit quality attributes were not influenced. The russet occurrence was lower not only in a single bag application than in untreated ones but also in yellow bagging and discolored bagging applications than in a white bagging application. The russet occurrence in a bagging application was lower at 20 DAFB than at 30 and 40 DAFB, while fruit quality attributes were not affected by bagging applications. The russet incidence was lower in $GA_{4+7}+BA$ twice treatments at 20 and 30 DAFB, and calcium coated bag at 30 DAFB after $GA_{4+7}+BA$ treatment at 20 DAFB than in untreated fruit. The rate of russet incidence was lowest at equator region in $GA_{4+7}+BA$ treatment, compared with the other fruit regions. Overall, the results suggest that one and/or two applications of $GA_{4+7}+BA$ (1,000-folds) treatment at 20 DAFB should reduce the risk of russet incidence in 'Gamhong' fruit.

• The Korean Journal of Pesticide Science
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• v.11 no.4
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• pp.238-245
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• 2007

This survey was performed to elucidate whether pesticide can cause the non-spinning syndrome of silkworm, Bombyx mori in Yecheon and Sangju 2002. We primarily focused to Insect Growth Regulator Pesticides(IGR) used in that areas. In the result of the survey to the retail pesticide store at Yecheon and Sangju, seven pesticides of the total 12 IGR pesticides sold were used during spring sericuitural season. 7 pesticides might effect on silkworm in consideration of possibility of exposure according to the characteristics of used amount, spray drift, volatility and treatment time. Five chitin synthesis inhibitor involving diflubenzuron of 7 IGR pesticides were known as very toxic to silkwork after exposure by skin and feeding but no non-spinning syndrome was observed from several papers. Methoxyfenozide and tebufenozide also has used at sericultural season, but are ecdysone agonist. One of the most feasible suspect of non IGR pesticide, was molinate in consideration of its volatility property and wide spread use in the sericultural area. But it's symptom after exposure of molinate was not the same as the non-spinning syndrome broke out at the sericultural farm in Yecheon and Sangju.

• Journal of Nutrition and Health
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• v.40 no.8
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• pp.736-744
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• 2007

Leptin, as an adipocyte-derived hormone, is an important regulator of food intake and energy expenditure. In the cross-sectional study, leptin was shown to be positively related to body adiposity and metabolic disorders in adults. However, there were very few studies which reported the leptin as a predictor of weight gain over time. We examined whether serum leptin can be used as an indicator of the present and 1-year past weight status in very young children. First grade students from elementary schools in Gwacheon City were enrolled in the study since 2005. The study subjects(total 375 students; 195 boys and 180 girls) participated in the investigation of both 2005 and 2006. Physical examinations including height, weight, waist circumference were done. To examine the prevalence of obesity, obesity index was used. Serum leptin was measured, and their nutritional status was also evaluated based on 3-Day dietary records. Serum leptin levels were strongly positively related with the value of the present BMI and with the value of the BMI one year before. We found no association with leptin levels and amount of energy intake and macronutrient intake in this children population. Children were divided into three groups according to leptin tertiles. The highest leptin tertile group showed highest prevalence of obesity in year 2006 as well as in year 2005. Serum leptin levels can reflect the weight status now and as well as 1-year before. Possibly serum leptin levels can predict the weight gain of year later. Without an action against the obesity on children with high leptin level, those children would maintain the excess adiposity growth and progress into the obesity-related metabolic disorders. Further studies are needed to predict the obesity as early as possible and preventive system then after.

• 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.