• 농업과학연구
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• 제44권4호
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• pp.477-486
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• 2017

This review provides an overview of dietary nucleotides as an alternative to in-feed antibiotics for weaning pigs. Dietary nucleotides are composed of DNA or RNA molecules and are normally contained in protein-rich feed ingredient, brewer's yeast, yeast extract, and milk. Weaning pigs are suffering from several stresses, such as environmental challenges (i.e. crowding, transportation, and feeding). Such stressors can damage the intestinal epithelium and cause an invasion by Escherichia coli, secondary inflammatory responses, and post weaning diarrhea. To overcome weaning disorder, people often use antibiotics which reduce symptoms and boost growth performance. However, since antibiotics were banned due to concerns of antibiotic resistant bacteria, researchers are studying alternative materials to antibiotics. Dietary nucleotides are one of the alternative materials for replacing antibiotics and can be used in abnormal conditions, such as weaning diarrhea, low digestibility, and disease condition. Nucleotides have substances that have important roles in cell division and cell growth, affecting growth performance, intestinal condition, and immunological effect at the weaning stage. However, nucleotides' composition is very different between sources and this aspect makes it difficult to utilize nucleotides at the weaning stage. Therefore, this review paper focuses on i) the characteristics and functions of dietary nucleotides and ii) the effect of dietary nucleotides on the growth performance and immune system of pigs.

• 한국식품과학회지
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• 제8권1호
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• pp.47-52
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• 1976

Aflatoxin이 함유된 TGY 액체배지(培地)에서 Bacillus megaterium NRRL B-1368 균주를 배양시 공시균(供試菌)의 생육저해(生育沮害), 형태적(形態的) 변화 및 정상(正常)배지에서의 생육회복(生育回復)과정을 조사하였다. Crude aflatoxin $(B_1\;22.7%,\;B_2\;1.6%,\;G_1\;3.6%,\;G_2\;0.2%)$의 농도 $20\;{\mu}g/ml$ 이상에서는 공시균(供試菌)의 생육(生育)이 완전히 억제(抑制)되었고 격막(隔膜)이 형성되지 않아 기형적(畸形的)으로 신장(伸長)하는 세포분렬의 장해현상을 보였다. 이들 기형(畸形)세포를 정상(正常)배지에서 다시 배양하면 격막이 형성되면서 정상(正常)세포로 분렬, 증식되었다. 따라서 aflatoxin은 세균의 격막형성에 관계하는 mesosome의 기능(機能)에 영향을 미치는 것으로 추론(推論)되었다.

• Reproductive and Developmental Biology
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• 제33권2호
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• pp.93-98
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• 2009

In this study, bovine Dnmt1 cDNA was sequenced and detected Dnmt1 mRNA level in bovine tissues by northern blot, methylation pattern of genome by southern blot, specific localization of Dnmt1 in mouse and bovine preimplantation embryos by immunocytostaining and Dnmt1 protein level in ovary and testis by western blot. Bovine Dnmt1 cDNA sequence showed more homology with that of human than mouse and rat. The RNA level of Dnmt1 was 10 times higher expression in placenta than other tissues. This indicates that placenta was hypermethylated compared to others organs. The genomic DNA could not be cut by a specific restriction enzyme (HpaII) in placenta, lung and liver of bovine. It suggests that Dnmt1 in some somatic cells was already methylated. Dnmt1, which has the antibody epitope 1316~1616, was distributed in nucleus and cytoplasm including the stage of pronuclear stage and maturation of oocyte and gradually weaken to blastocyst stage compare to negative. In addition, Dnmt1 was strongly expressed in tetraploid embryo and cloned 8-cell than IVF 8-cell. An aberrant pattern of DNA methylation in cloned embryo may be abnormal development of fetus, embryonic lethality and placenta dysfunction. The somatic specific band (190kDa) was appeared in ovary and testis, but oocyte specific band (175kDa) was not. Further investigations are necessary to understand the complex links between the methyltransferases and the transcriptional activity of genes in the cloned bovine tissues.

• 식물조직배양학회지
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• 제25권3호
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• pp.153-158
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• 1998

Arabidopsis thaliana에 beet curly top virus (BCTV)를 인공접종하여 외부병징 및 조직내부구조 변화를 광학현미경으로 검경하였다. BCTV-Logan에 접종된Arbidopsis thaliana ecotype Sei-O 줄기에서 약 2주 후 이상비대현상이 관찰되었고, 약 4주 후에는 캘러스조직이 형성되었다. 감염된 각 시기별로 증상부위의 Sei-O 줄기를 횡단절단하여 관찰한 결과 다음과 같은 순서, (1) 사부조직의 이상비대, (2) 이상비대된 사부의 괴사, (3) 괴사조직의 lacuna 형성, (4) lacuna형성된 사부 주위의 피층과 표피세포 신장 및 확대, (5) 신장된 피층 및 표피세포에서의 세포분열 유도, (6) 캘러스 조직의 유도 순으로 내부구조 변화가 관찰되었다. BCTV에 감염된 Arabidopsis에서의 캘러스 형성은 바이러스의 감염결과로 유도되었으며, azure-A염색법에 의해 바이러스 inclusion body는 사부조직과 캘러스에서도 존재함이 관찰되었다. 본 연구 결과 BCTV에 감염된 Arabidopsis에서 관찰된 캘러스 형성의 원인은 감염된 숙주식물의 사부조직의 괴사에 따른 lacuna 주위 피층세포의 세포분열에 기인한 것으로 사료된다.

• 생명과학회지
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• 제15권1호
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• pp.124-131
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• 2005

세포주기 조절에서 유전자 발현의 조절은 매우 중요한 부분이다. 본 연구에서는 인간의 유전자인 SMARCADl과 상동성을 가지는 분열형 효모의 새로운 유전자 $mas3^+$를 분리하였다. 이 두 유전자는 $87\%$의 상동성을 보인다. $mas3^+$유전자는 DEAD/H box를 포함한 7개의 motif를 가지고 있어서 helicase superfamily 중에서도 SNF2 family에 속한다. kanMX6를 선별 표지로 이용하여 $mas3^+$유전자 결손 세포를 구성하였고 $mas3^+$ 유전자 결손 세포는 UV와 MMS처리 실험에서 정상의 세포와 생존율이 비슷하여 DNA상해회복과는 관련이 없음을 알 수 있었다. $mas3^+$ 유전자의 세포주기별 발현 양을 분석한 결과 $G_2$단계부터 점차적으로 발현양이 늘어났다. $mas3^+$결손 돌연변이를 $26^{\circ}C$와 $35^{\circ}C$에서 배양한 결과, 비정상적인 세포질 분열 과정으로 인해 다중 격막 세포의 빈도가 증가하였다. 이상의 결과들은 $mas3^+$유전자는 세포질 분열과 세포형태 형성에 연관되어 있음을 시사한다.

• 동의생리병리학회지
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• 제28권6호
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• pp.621-629
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• 2014

This study aimed to evaluate the genotoxicity of GST (Gamisasangja-tang). For examining genotoxicity, we carried out bacterial reverse mutation assay, chromosome aberration assay, micronucleus induction test according to OECD guidelines. Bacterial reverse mutation assay: In GST treating group, regardless of existence S9 mix, revertant colonies counts appeared to be less than twice of negative control group and dose dependent increase. In positive control group, revertant colonies counts were shown to be more than twice of negative control croup. Chromosome aberration assay: All cell line showed repetition rate of abnormal chromosome aberration less than 5%, regardless of treating time, existence of S9 mix, and no significant change ($p{\succeq}0.05$) compared with negative control group. Micronucleus induction test: Micronucleated polychromatic erythrocytes (MNPCE) repetition rate of Polychromatic erythrocytes (PCE) showed no significant changes compared with negative control group ($p{\succeq}0.05$). PCE portion of total erythrocytes also showed no significant changes ($p{\succeq}0.05$). Our results showed that GST didn't induce any genotoxicity.

• 한국발생생물학회지:발생과생식
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• 제18권4호
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• pp.197-212
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• 2014

Osteosarcoma (OS) is one of the most common malignant primary bone tumors and NF-${\kappa}B$ appears to play a causative role, but the mechanisms are poorly understood. OS is one of the pleomorphic, highly metastasized and invasive neoplasm which is capable to generate osteoid, osteoclast and osteoblast matrix. Its high incidence has been reported in adolescent and children. Cell signal cascade is the pivotal functional mechanism acquired during the differentiation, proliferation, growth and survival of the cells in neoplasm including OS. The major limitation to the success of chemotherapy in OS is the development of multidrug resistance (MDR). Answers to all such queries might come from the knock-in experiments in which the combined approach of miRNAs with NF-${\kappa}B$ pathway is put into use. Abnormal miRNAs can modulate several epigenetical switching as a hallmark of number of diseases via different cell signaling. Studies on miRNAs have opened up the new avenues for both the diagnosis and treatment of cancers including OS. Collectively, through the present study an attempt has been made to establish a new systematic approach for the investigation of microRNAs, bio-physiological factors and their target pairs with NF-${\kappa}B$ to ameliorate oncogenesis with the "bridge between miRNAs and NF-${\kappa}B$". The application of NF-${\kappa}B$ inhibitors in combination with miRNAs is expected to result in a more efficient killing of the cancer stem cells and a slower or less likely recurrence of cancer.

• 생명과학회지
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• 제31권3호
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• pp.266-279
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• 2021

본 연구에서는 다양한 사람의 암세포주(A-549, MCF-7, MDA-MB-231, U87-MG, AGS, MKN-74 및 SNU-601 세포)와 정상세포주(MRC-5 섬유아세포 및 사랑니 유래 중간엽성 줄기세포에 토복령 추출물(Smilax china L. extract, SCLE)을 처리하여 세포 사멸 효과를 조사하였다. SCLE 처리 후, MTT 분석에서 여러 암세포주는 정상세포주보다 유의적으로 휠씬 낮은 반억제농도값을 나타내었고, 세포는 세포부착력의 소실로 인한 세포사멸(anoikis)이 관찰되었다. 또한, SCLE를 처리한 A-549, AGS 및 MCF-7 암세포주에서 세포의 생존성과 말단소립 복원효소의 활성도를 조사하였을 때, SCLE 처리 후 4일째에 세포의 생존성과 말단소립 복원효소의 활성도가 현저히 줄어드는 것을 관찰하였다. 또한, SCLE를 처리한 A-549, AGS 및 MCF-7 암세포주에서 세포 주기의 G1기에서 세포 성장이 정지되었고,세포 사멸이 유의적으로 증가하는 것을 알 수 있었다. 그러나, SCLE 처리는 rho 단백질의 활성과 관련 없는 세포부착력의 소실과 세포 사멸이 유도되는 것을 관찰하였다. 이 연구의 결과를 바탕으로 토복령 추출물은 정상 세포보다는 암세포에 특이적으로 세포부착력의 소실과 세포 사멸을 유도하여, 이 추출물에 포함된 물질을 이용한 항암 연구에 응용될 수 있을 것으로 판단된다.

• Journal of Microbiology and Biotechnology
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• 제27권5호
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• pp.878-895
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• 2017

Phosphorylation, a critical mechanism in biological systems, is estimated to be indispensable for about 30% of key biological activities, such as cell cycle progression, migration, and division. It is synergistically balanced by kinases and phosphatases, and any deviation from this balance leads to disease conditions. Pathway or biological activity-based abnormalities in phosphorylation and the type of involved phosphatase influence the outcome, and cause diverse diseases ranging from diabetes, rheumatoid arthritis, and numerous cancers. Protein tyrosine phosphatases (PTPs) are of prime importance in the process of dephosphorylation and catalyze several biological functions. Abnormal PTP activities are reported to result in several human diseases. Consequently, there is an increased demand for potential PTP inhibitory small molecules. Several strategies in structure-based drug designing techniques for potential inhibitory small molecules of PTPs have been explored along with traditional drug designing methods in order to overcome the hurdles in PTP inhibitor discovery. In this review, we discuss druggable PTPs and structure-based virtual screening efforts for successful PTP inhibitor design.

• Preventive Nutrition and Food Science
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• 제10권2호
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• pp.161-166
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• 2005

We investigated the effect of pycnogenol (PYC) supplementation on retarding the immune dysfunction of CS7BL/6 mice after murine AIDS (MAIDS) development. Dysfunction of T and B cell mitogenesis from primary cultured splenocytes has been observed with retrovirus infection and PYC supplementation partially recovered the dysfunction of T and B cells. There was an abnormal shift of cytokine pattern with retrovirns infection, which was designated by the decreased secretion of Th1 cytokines and increased secretion of Th2 cytokines. PYC supplementation increased IL-2 and $IFN-\gamma$ secretion and decreased IL-4, IL-6, and $TNF-\alpha$ secretion, but it was not sufficient enough to maintain the normal level of these cytokines. Hepatic vitamin E level was significantly decreased by retrovirns infection, in accordance with increased hepatic lipid peroxidation level, whereas PYC supplementation normalized the hepatic level of vitamin E and lipid peroxidation. This study suggests that PYC supplementation may partially help retard the incidence of symptoms during MAIDS.