• Development and Reproduction
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• v.7 no.2
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• pp.119-126
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• 2003

In the previous study, we obtained list of differentially expressed genes between postnatal day 1 and day 5 mouse ovaries using suppression subtractive hybridization(SSH) and found that MT Oansposon-like element, clone MTi7(MTi7) was one of the highly expressed genes in the day 5 mouse ovary(Park et at., 2002). Results of in situ hybridization and RNA interference revealed that the expression of MTi7 is oocyte-specific in the ovary and may be involved in the regulation of oocyte maturation(Park et at., 2003). At present, MTi7 sequence has been known only in the mouse. Therefore, the present study was accomplished 1) to identify MTi7 sequence in the other mammalian species, such as bovine, porcine, rat, and human, and 2) to evaluate the flanking sequence of the mouse MTi7 since it has transposon characteristics. Using ovarian cDNAs derived from low different species, we cloned and identified new MTi7 sequence showing a high degree of sequence homology with the mouse MTi7(87∼98%). By using inverse PCR, we found that the mouse MTi7 may intercalated the beta-carotene 15, 15'-monooxygenase(Bcdo) gene and/or serine protease inhibitor, Kunitz Dpe I(Spint 1) gene. By finding the MTi7 sequences in the other mammalian species and the flanking gene of the MTi7 in mouse, it is expected to reveal the role(s) of MTi7 in the oogenesis as well as folliculogenesis in the near future.

• Journal of the Korean Applied Science and Technology
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• v.37 no.5
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• pp.1239-1247
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• 2020

Sedum kamtschaticum Fisch., a native plant of Korea, has been used in Korean traditional medicine in the form of water extract for its capacity to improve blood circulation and for its antioxidant and anti-inflammatory effects. Since previous research suggests that S. kamtschaticum Fisch. has excellent antioxidant and mushroom tyrosinase inhibition activities, in this study, the root and stem parts of S. kamtschaticum Fisch. are extracted in 70% ethanol (SKS, SKR), fractionated with and in order of n-hexane (SSH), ethyl acetate (SSE, SRE), chloroform (SSC, SRC) and water (SSW, SRW) according to the polarity of each solvent, and tested for its applicability as a cosmetic material. According to the total polyphenol, flavonoid contents and DPPH radical scavenging activity of each fraction, the contents and scavenging activity of the root extractions (SKR) were higher than those of the stem extractions (SKS), ethyl acetate fractions (SSE, SRE) being the most effective. In addition, ethyl acetate fractions had the highest tyrosinase inhibition activity and melanin synthesis inhibition activity used on B16F10 melanoma cells, at the concentration of 10 ㎍/mL. HPLC analysis detected a variety of polyphenols including gallic acid and quercetin. This study suggests the potential role of S. kamtschaticum Fisch. as a natural cosmeceutical material.

• Journal of Plant Biotechnology
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• v.29 no.2
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• pp.99-104
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• 2002

Suppression subtractive hybridization (SSH) was used to isolate wound-induced cDNAs from wounded soybean. One of low-temperature-inducible cDNA, slti182 showed high homology with genes encoding 1-asparaginase. The full length cDNA of slti182, deginated GmASP1, is 1258 bp long and contains an open reading frame consisted of 326 amino acids. CmASP1 protein showed the highest identity (84%) with putative asparaginase from A. thaliana (AB012247), but it showed only 55% identity with another isoform of A. tathaliana (Z34884). The expression of GmASP1 during low temperature stress started to increase 3 hours after treatment, reached the maximum at 6 hour, and then decreased to the initial level at 48 hours. The amount of GmASP1 transcripts increased again when low-temperature-treated plants were transferred to room temperature, The present study suggests that GmASP1 may function to accelerate the protein synthesis which is important in the early response to low temperature.

• Journal of the Korean earth science society
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• v.23 no.4
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• pp.349-356
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• 2002

In an effort to properly assess the validity of spaceborne radar altimeter measurements, we made a direct comparison of two different sea surface heights (SSH) acquired by both Topex/Poseidon (T/P) satellite and in-situ tide-gauges (T/G). This comparative analysis was conducted using the data sets collected from three locations along the eastern coast of Korea which include: Ulleungdo, Pohang, and Sokcho. In the course of the analysis of satellite altimeter, information of SSH was extracted from the T/P MGDR data sets through the application of both atmospheric and geophysical corrections. To compare the T/P data sets in parallel basis, the T/G data sets were averaged using the measured values within the peripheral radius of 55km. When compared among different locations, the compatibility between the two methods was much more significant in an offshore location (Ulleungdo) than the two onshore locations (Pohang, Sokcho). If the low-pass filtered results were compared among the sites, the offshore site exhibited the best correlations between the two methods (correlation coefficient of 0.91) than those of the onshore sites. These large differences in the strength of correlations among different locations are due to the deformation of M2, S2, and K1 tidal components used in the tidal model. In case of the offshore location, the compatibility of the two different methods were improved systematically by the low-pass filtering with an increase of the filtering duration such as up to 200 days.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.20 no.6
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• pp.183-194
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• 2010

A company's private network protected by a firewall and NAT(Network Address Translation) is not accessible directly through an external internet. However, as Reverse Connection technology used by NetCat extends to the technologies such as SSH Tunnel or HTTP Tunnel, now anyone can easily access a private network of corporation protected by a firewall and NAT. Furthermore, while these kinds of technologies are commercially stretching out to various services such as a remote control and HTTP Tunnel, security managers in a company or general users are confused under the circumstances of inner or outer regulation which is not allowed to access to an internal system with a remote control. What is more serious is to make a covert channel invading a company's private network through a malicious code and all that technologies. By the way, what matters is that a given security system such as a firewall cannot shield from these perceived dangers. So, we analyze the indirect access of technological methods and the status quo about a company's internal network and find a solution to get rid of the related dangers.

• Parasites, Hosts and Diseases
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• v.21 no.1
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• pp.11-18
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• 1983

As a part of observation on the suitability as a second intermediate host of Clonorchis sinensis, various infection experiments were tried to Cyprinus carpio nodus. The results obtained were summarized as follows: 1. The cercariae which attempted to contact with Cyprinus carpio nodus in the water were observed under the stereomicroscope. After contact, cercariae began to separate its tails from the bodies at 4 minutes increasingly, and then the numbers ranged to 80% at 13 minutes after the encounter. But very few cercariae could actually invade into the epidermis of the fish. 2. When Cyprinus carpio nudes were exposed to a number of cercariae in the beaker, only a few cercariae could invade through the epidermis. Most of the invaded cercariae were killed before forming the cyst. Also rare encysted cercariae were found to be dead within 48 hours. 3. Cyprinus carpio nudes were reared with Parafossarulus manchouricus shedding numerous cercariae in the indoor aquarium. When observed after 12 days, to determine the susceptibility, no metacercaria was found infected. 4. Cyprinus carpio nudum were reared with Parafossarulus manchouricus shedding numerous cercariae in Kimhae lake for 2 months in summer of 1982, in order to check the natural infection. No metacercaria of Clonorchis sinensis was found from the fish. 5. In the cases of control fish, Pseudoraibora larva, numerous cercariae were inspected on the course of invasion through epidermis of the fish under the stereomicroscope. And many metacercariae were also found from the Ssh whenever they were kept in beaker, indoor aquarium, or the lake for natural infection. The results suggested that Cyprinus carpio kudus might not be proper intermediate host of Clonorchis sinensis.

• International Journal of Industrial Entomology and Biomaterials
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• v.33 no.2
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• pp.102-107
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• 2016

Stress may be defined as any modification of environmental parameters that leads to a response by biological organisms. Stresses that affect biolpgical structures may be nonthermal, such as ultraviolet radiation, pH, or salinity, or thermal. Temperture is one of the major stresses that all living organism face. The major effects of cold(low emperature) are decrease of membrane fluidity and the stabilization of secondary structures of RNA and DNA in the cells, which may effect the efficiency of translation, transcription, and DNA replication. In this study, we focus on discovering the genes that are expressed by the cold(low temperature) stress in the silkworm. In cold(low temperature) stress test, we found 100% survive from cold stress at $0^{\circ}C$ up to 12h and $-5^{\circ}C$ up to 2h, and then, survive rate was rapidly decrease in silkworm. Thereafter two whole genes have selected by SSH(Suppression subtractive hybridization). (GenBank accession : GQ149511, GQ338156)

• Molecules and Cells
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• v.23 no.1
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• pp.100-107
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• 2007

The moss Physcomitrella patens has two life cycles, filamentous protonema and leafy gametophore. A modified from of suppression subtractive hybridization (SSH), mirror orientation selection (MOS), was applied to screen genes differentially expressed in the P. patens protonema. Using reverse Northern blot analysis, differentially expressed clones were identified. The identified genes were involved mainly in metal binding and detoxification. One of these genes was an AP2 (APETALA2) domain-containing protein (PpACP1), which was highly up-regulated in the protonema. Alignment with other AP2/EREBPs (Ethylene Responsive Element Binding Proteins) revealed significant sequence homology of the deduced amino acid sequence in the AP2/EREBP DNA binding domain. Northern analysis under various stress conditions showed that PpACP1 was induced by ethephon, cadmium, copper, ABA, IAA, and cold. In addition, it was highly expressed in suspension-cultured protonema. We suggest that PpACP1 is involved in responses to metals, and that suspension culture enhance the expression of genes responding to metals.

• Journal of Pharmacopuncture
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• v.16 no.1
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• pp.30-36
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• 2013

Objective: Panax ginseng is one of the most medicinally used herbal medicines in the world. Wild ginseng is widely accepted to be more active than cultivated ginseng in chemoprevention. However, little has actually been reported on the differences between wild ginseng and cultivated ginseng. Method: To identify wild ginseng-specific genes, we used suppressive subtraction hybridization. Results: We report that one of the clones isolated in this screen was the GAPDH (glyceraldehyde 3-phosphate dehydrogenase) gene (designated pGAPDH-w). DNA BLAST sequence analysis revealed that this pGAPDH-w gene contained novel sequences of 94 bp. RT-PCR results showed that the expression of the pGAPDH-w gene was significantly up-regulated in the wild ginseng as compared with the cultivated ginseng. Conclusion: The pGAPDH-w gene may be one of the important markers of wild ginseng.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.48-48
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• 2003

본 실험은 spermatogonia 단계에 발현하는 유전자를 찾기 위하여 suppression subtractive hybridization를 수행하였다. 기존에 mouse에서는 spermatogonia 특이적인 유전자들이 밝혀져 있기 때문에 pig에 특이적인 유전자를 찾기 위하여 pig 250days testis와 pig 60days testis를 재료로 하여 실험하였다. SSH를 통하여 254days testis에 특이적으로 발현되는 후보유전자를 7개 찾았고 25days testis와 60days testis 의 Northern blot을 통하여 25days에 과발현하고 60days에 발현의 양이 대폭 줄어드는 spermatogonia 유전자로 생각되는 후보유전자 2개를 선택하여 pig tissue northern blot, genomic DNA southern blot, RT-PCR 그리고 In-situ hybridization을 수행하였다. Tissue northern blot과 RT-PCR을 통하여 후보자 1번은 간과 폐, 난소, 정소에서 발현하고, 후보유전자 15번은 난소와 정소에서만 특이적으로 발현함을 알았다. DNA sequence analysis와 NCBI Blast search를 통하여 후보자 1번은 다른 종에서 밝혀진 유전자였고 후보유전자 15번은 어느 종에서도 밝혀지지 않은 새로운 유전자였다. Degenerated primer를 통하여 후보자 1번의 pig full sequence를 밝히고 NCBI에 등록하였다. 그리고 In-situ hybridization을 통하여 후보유전자득이 20일째 testis의 Leydic cell에서 많이 발현되고 adult testis에서는 발현이 감소하는 결과를 얻었다. 이것으로 보아 위의 두 후보유전자는 spermatogonia에 직접 관련된 유전자이기 보다는 spermatogonia의 발달에 영향을 주는 leydic cell 특이발현을 가진 유전자로 사료되어진다.