• Journal of Plant Biotechnology
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• v.43 no.3
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• pp.261-271
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• 2016

Citrus is an economically important fruit crop widely growing worldwide. However, citrus production largely depends on natural hybrid selection and bud sport mutation. Unique botanical features including long juvenility, polyembryony, and QTL that controls major agronomic traits can hinder the development of superior variety by conventional breeding. Diverse factors including drastic changes of citrus production environment due to global warming and changes in market trends require systematic molecular breeding program for early selection of elite candidates with target traits, sustainable production of high quality fruits, cultivar diversification, and cost-effective breeding. Since the construction of the first genetic linkage map using isozymes, citrus scientists have constructed linkage maps using various DNA-based markers and developed molecular markers related to biotic and abiotic stresses, polyembryony, fruit coloration, seedlessness, male sterility, acidless, morphology, fruit quality, seed number, yield, early fruit setting traits, and QTL mapping on genetic maps. Genes closely related to CTV resistance and flesh color have been cloned. SSR markers for identifying zygotic and nucellar individuals will contribute to cost-effective breeding. The two high quality citrus reference genomes recently released are being efficiently used for genomics-based molecular breeding such as construction of reference linkage/physical maps and comparative genome mapping. In the near future, the development of DNA molecular markers tightly linked to various agronomic traits and the cloning of useful and/or variant genes will be accelerated through comparative genome analysis using citrus core collection and genome-wide approaches such as genotyping-by-sequencing and genome wide association study.

• Journal of radiological science and technology
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• v.27 no.3
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• pp.5-12
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• 2004

I. Introduction : The constipation is one of the common gastrointestinal symptoms seen in the clinical practice. When people come to the clinic complaining of the constipation, it is generally one of the cases of infrequent, painful or difficult evacuation as well as the hardened feces and unsatisfactory evacuation sense. Since the constipation is heavily influenced by dietary habit as well as the social and medical environment, the diagnostic radiology is useful to establish the objective and standardized definition in consideration of those various factors before diagnosis and treatment of the constipation patient. This paper describes the study of such diagnosis. II. Main Subject : Testing of CTT (colon transit time) is key study of the colon performance. CTT is very helpful in classifying the pathologic physiological types and defining the treatment plan for the chronic constipation. The study methods include using the radipaque marker, multiple marker technique and scintigraphic measurement. The defecography is the functional radiologic examination a that provides not only the anatomical information of anorectal but also performance of the pelvic floor and rectal change during evacuation. Study of dynamic movement of the anorectal during evacuation is helpful for diagnosis and treatment planning as well as follow-up testing for the constipation patient. One of the issues essential for the case history is the thorough observation of whether the patient shows the psychic psychological symptoms such as the behavior disorder or emotional disturbance. In that case, the decision must be made whether or which type of medication is needed for such psychiatric problem. III. Conclusion : The main causes of the constipation are insufficient intake of fiber or liquid. The key objective of such tests is to check etiology of the constipation. In general, the radiological examination does not provde the colon or anorectal performance information. It is envisaged that this study will provide the information to decide the testing and treatment plans and predict the prognosis of the patient by classifying the pathologic physiological types.

• Journal of radiological science and technology
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• v.34 no.1
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• pp.17-25
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• 2011

In this study, we examined the impact caused by chronic exposure to Mn by investigating the degree of brain activation based on the data of recognition activities using fMRI (functional magnetic resonance imaging). A questionnaire survey, blood tests, and fMRI tests were carried out with respect to two groups. Group 1 was an exposure group consisting of 15 male workers who are 34 years old or older, and who worked for longer than 10 years in a shipbuilding factory as a welder. Group 2 was a control group consisting of 15 workers in manufacturing industries with the same gender and age. The results showed that blood Mn concentration of Group 1($1.3\;{\mu}g/dl$) was significantly higher than that of Group 2($0.8\;{\mu}g/dl$)(p < 0.001), and Pallidal Index (PI) of Group 1 was also significantly higher than that of Group 2 (p < 0.001). PI value of the group whose blood Mn concentration was $0.93\;{\mu}g/dl$ or higher was significantly higher than that of the group whose blood Mn concentration was less than $0.93 \;{\mu}g/dl$ (p < 0.001). As for brain activity area within the control group, the right and the left areas of occipital cortex showed significant activity and the left area of middle temporal cortex, the right area of superior inferior frontal cortex and inferior parietal cortex showed significant activity. Unlike the control group, the exposure group showed significant activity on the right area of superior inferior temporal cortex, the left of insula area. In the comparison of brain activity areas between the two groups, the exposure group showed significantly higher activation than the control group in such areas as the right inferior temporal cortex, the left area of superior parietal cortex and occipital cortex, and cerebellum including middle temporal cortex. However, in nowhere the control group showed more activated area than the exposure group. As the final outcome, chronic exposure to Mn increased brain activity during implementation of arithmetic task. In an identical task, activation increased in superior inferior temporal cortex, and insula area. And it was discovered that brain activity increase in temporal area and occipital area was more pronounced in the exposure group than in the control group. This result suggests that chronic exposure to Mn in the work environment affects brain activation neuro-network.

• Journal of radiological science and technology
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• v.40 no.1
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• pp.41-47
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• 2017

Considering that the X-ray apron used in the department of radiology is also used in the department of nuclear medicine, the study aimed to analyze the shielding rate of the apron according to types of radioisotopes, thus ${\gamma}$ ray energy, to investigate the protective effects. The radioisotopes used in the experiment were the top 5 nuclides in usage statistics $^{99m}Tc$, $^{18}F$, $^{131}I$, $^{123}I$, and $^{201}Tl$, and the aprons were lead equivalent 0.35 mmPb aprons currently under use in the department of nuclear medicine. As a result of experiments, average shielding rates of aprons were $^{99m}Tc$ 31.59%, $^{201}Tl$ 68.42%, and $^{123}I$ 76.63%. When using an apron, the shielding rate of $^{131}I$ actually resulted in average dose rate increase of 33.72%, and $^{18}F$ showed an average shielding rate of -0.315%, showing there was almost no shielding effect. As a result, the radioisotopes with higher shielding rate of apron was in the descending order of $^{123}I$, $^{201}Tl$, $^{99m}Tc$, $^{18}F$, $^{131}I$. Currently, aprons used in the nuclear medicine laboratory are general X-ray aprons, and it is thought that it is not appropriate for nuclear medicine environment that utilizes ${\gamma}$ rays. Therefore, development of nuclear medicine exclusive aprons suitable for the characteristics of radioisotopes is required in consideration of effective radiation protection and work efficiency of radiation workers.

• Journal of Life Science
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• v.25 no.1
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• pp.53-61
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• 2015

In this study, we tried to separate the photosensitizer that induces apoptosis of leukemia cells (U937) from perilla leaves. Perilla leaves (Perilla frutescens Britt var. japonica Hara) are a popular vegetable in Korea, being rich in vitamins (A and E), GABA, and minerals. Dried perilla leaves were extracted with methanol to separate the photosensitizer by various chromatographic techniques. The structure of the isolated compound (PL9443) was identified by 1D-NMR, 2D-NMR, and FAB-mass spectroscopy. Absorbance of the UV-Vis spectrum was highest at 410 nm and was confirmed by the 330, 410, and 668 nm. PL9443 compound was determined to be pheophorbide, an ethyl ester having a molecular weight of 620. It was identified as a derivative compound of pheophorbide structure when magnesium comes away from a porphyrin ring. Observation of morphological changes in U937 cells following cell death induced by treated PL9443 compound revealed representative phenomena of apoptosis only in light irradiation conditions (apoptotic body, vesicle formation). Results from examining the cytotoxicity of PL9443 substance against U937 cells showed that inhibition rates of the cell growth were 99.9% with the concentration of 0.32 nM PL9443. Also, the caspase-3/7 activity was 99% against U937 cells with the concentration of 0.08 nM of PL9443 substance. The result of the electrophoresis was that a DNA ladder was formed by the PL9443. The PL9443 compound is a promising lead compound as a photosensitizer for photodynamic therapy of cancer.

• Journal of Life Science
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• v.19 no.12
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• pp.1737-1742
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• 2009

It has been known that Linum usitatissimum and Perilla frutescens are dietary sources of possible chemopreventive compounds such as lignans and $\alpha$-linolenic acid. Here, we investigated and compared the inhibitory effects of methanol extracts from Linum usitatissimum and Perilla frutescens on mutagenicity using the Ames test, and growth of human cancer cells (AGS human gastric adenocarcinoma, HT-29 human colon cancer, Hep 3B hepatocellular carcinoma cells). In the Ames test system using Salmonella typhimurium TA100, aflatoxin $B_1$ ($AFB_1$)-induced mutagenicity was significantly inhibited by treatment with the methanol extract from either Linum usitatissimum or Perilla frutescens (p<0.05) in a dose dependent manner. As for N-methyl-N'-nitro-N-nitrosoguamidine (MNNG)-induced mutagenicity, the methanol extracts (5 mg/assay) from Linum usitatissimum and Perilla frutescens showed 63% and 78% inhibitory rates, respectively, indicating that Perilla frutescens possessed stronger antimutagenic activity than did Linum usitatissimum. Inhibitory effects of methanol extracts from Linum usitatissimum and Perilla frutescens on the growth of human cancer cells (AGS, HT-29 and Hep 3B) appeared to increase dose dependently, and the inhibition was more effective against AGS and HT-29 compared to Hep 3B cells. Our results suggested that the methanol extract from Perilla frutescens showed stronger antimutagenic activity than that from Linum usitatissimumas assayed by the Ames mutagenic test, whereas the methanol extract from Linum usitatissimum was more effective than its counterpart for growth inhibition of human cancer cells. It is concluded that intake of Linum usitatissimum and Perilla frutescens as sources of omega-3 fatty acids will be beneficial for preventing cancer.

• Journal of Life Science
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• v.19 no.1
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• pp.58-64
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• 2009

This study was conducted to know the molting sequence and the aging points of flight feathers of steller's sea eagles (Haliaeetus pelagicus). For this study, two captive immature steller's sea eagles raised at the Ornithology Laboratory attached to Kyungsung University were surveyed for five years from Nov. 2000 to Nov. 2005. The survey indicated that the first molting began in July of the second year, and the primaries of P1-3, the secondaries of S18-19 (female), S17-18 (male), and S1 and S4 were replaced by one-time with second generation feathers. Generally molting stopped during the winter period, but a few feathers continued to molt during the winter. The two secondaries of S18-19 (female) and S17-18 (male) always molted every year but some of the juvenile secondaries (male: S10, S11, etc) retained for 2 or 3 years. In the molting order of primaries, the first molting started at P1 and it proceeded to P10 of outside. In the secondaries, the first molting started at S17(male) and S19(female), and it proceeded to outside. After that molting it started at S1 and proceeded to inside. In the other secondaries, the pattern of molting which proceeded in the mid-part of the secondaries was usually beginning in several different points at the same time. The molting seemed as if it depends on both the conditions of the individuals and the environment, so it was very difficult to explain the molting pattern in the mid-part of the secondaries. The longer quills (P7, P8) required for more than 68 days to develop. In the comparison of the length in the remiges between the first and the second generation feathers, the first generation feathers were the larger than that of the second. And the reduction of the length between the second and the third generation feathers was a few. The reduction of the length between the third and the fourth generation feathers was slight. The juvenile primaries were dark brown with a whitish base, which could be observed until the second or the third generation feathers (in their third or fourth winter plumage).

• Journal of Life Science
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• v.30 no.2
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• pp.156-161
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• 2020

Since industrialization, the production and utilization of various chemicals has contributed to improving the quality of our lives, but the subsequent discharge of massive waste is inevitable, and environmental pollution is becoming more serious every day. Exposure to chemicals as a result of environmental pollution is having a negative effect on human health and the ecosystem, and cleaning up the polluted environment that can affect our lives is a very important issue. Toxic aromatic compounds have been detected frequently in soil, groundwater, and wastewater because of the extensive use of oil products, and phenol, which is used to produce synthetic resins, textiles, and dyes, is one of the major pollutants, along with insecticides and preservatives. Phenol can cause dyspnea, headache, vomiting, mutation, and carcinogenesis. Phenol-degrading bacterium DWB-1-8 was isolated from the activated sludge of textile wastewater; this strain was identified as Comamonas testosteroni by 16S rRNA gene sequencing. The optimal culture conditions for the cell growth and degradation of phenol were 0.7% K₂HPO₄, 0.6% NaH₂PO₄, 0.1% NH₄NO₃, 0.015% MgSO₄·7H₂O, 0.001% FeSO₄·7H₂O, an initial pH of 7, and a temperature of 30℃. The strain was also able to grow by using other toxic compounds, such as benzene, toluene, or xylene (BTX), as the sole source of carbon.

• Journal of Food Hygiene and Safety
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• v.23 no.4
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• pp.297-303
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• 2008

Naringin, major citrus flavonoids, has been identified to exert antioxidative, antidiabetic, and lipid lowering effects. In this study, we examined the effect of 0.2 g/kg, 0.5 g/kg naringin supplementation for 3 times/week for 5 weeks on lipid metabolism and antithrombotic capacity in rat. Eighteen five week-old Sprague Dawley(SD) female rats, which had initial body weights of $246{\pm}9g$, were randomly divided into three groups: Control (non naringin group); Low (0.2 g/kg naringin-supplemented group); High (0.5 g/kg naringin-supplemented group). Three groups of rats were supplemented with three experimental diets for 5 weeks and we investigated antithrombotic capacity before sacrifice. Naringin did not significantly alter the body weight gain, relative organ weight. However, the level of serum triglyceride, serum free fatty acid, serum total lipid and serum glucose levels were significantly lowered compared to those of control. The high group (0.5 g/kg naringin-supplemented group) was showed significantly increased bleeding time compared to control group. These results suggest that naringin supplemental diets reduces the level of hypertension, glycosuria and fatness on the female SD rats, when orally administered below the dosage 0.5 g/kg for 5 weeks.

• Applied Biological Chemistry
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• v.8
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• pp.95-100
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• 1967

A quantitative study on the mercury residue in the brown rice of "Paldal", a recommended rice variety in Korea, was carried out by changing the date and frequency of application with different forms of organo-mercury fungicide(PMA), which is used for the control of rice blast. The results are summarized follows: 1) Mercury residues were higher with the emulsion formulation(0.21 ppm) than the dust formulation (0.16 ppm) when they were used for the control of leaf blast on July 13. 2) In case when both of the emulsion and dust formulations were used on July 13 and August 13, respectively, the mrecury residues were lower in the treatment on July 13 (0.216 and 0.16 ppm) than in the treatment on August 13 (0.304 and 0.238 ppm). 3) In an emulsion formulation was applied once on August 13, the mercury residue was 0.304 ppm and its application in twice on July 13 and August 13, the residue was counted 0.32 ppm. In case of dust formulation, the residues were observed 0.238 ppm in a single dose and 0.276 ppm in double application. 4) When the fungicide was applied to the rice plant on August 13, the mercury residues in brown rice, rice bran, and stalk and leaves were 0.304, 0.323, and 0.676 ppm, respectively found in the case of emulsion and in the case of dust formulation, they were 0.238, 0.283 and 0.698 ppm, respectively. The mercury residue, in general, were less in the case of dust than in the case of emulsion formulation and lowered by a single treatment than by two times application and it was also less by treating on July 13 than by treating on August 13.