한국 재래계의 텔로미어 길이의 유전력과 유전양상 분석

박단비,조은정,손시환 한국가금학회 2013 한국가금학회 정기총회 및 학술발표회 Vol.2013 No.11

한국인 영어 학습자의 등급화된 즉흥 발화 OPic 음성자료의 초분절적 특징 연구

박단비,이석재 국제언어인문학회 2019 인문언어 Vol.21 No.2

In this study, we analyzed 60 Korean learners’ suprasegmental features from the OPIc speech data administered by the ACTFL committee. According to the evaluation method prescribed by the ACTFL committee, the data are classified into six grades from the lowest IL to the highest AL, and it is meaningful that they can examine the spontaneous speech of Korean learners. Pauses, speech rate and F0 range were analyzed using the Praat speech analysis program. Pause duration was measured by detecting the silent period over 250ms. The speech rate was calculated by dividing the time spent on speaking sentence by the syllable per sentence. The F0 range was measured as the pitch curve of the sentence. The result of the study can be derived as follow: Factors that differ among the six groups of different grades and that appear to have high influence on grading are the inter-sentential pause duration, intra-sentential pause duration, and speech rate. In other words, the higher the grade, the shorter the duration of the pauses and the faster the speech rate. There were no statistically significant differences between the grades in the intra-sentential pause frequency and the F0 range.

육계에 비타민 C 및 E의 첨가 급여가 telomere 함량 및 스트레스 연관 DNA 유전자 발현에 미치는 영향

박단비,조은정,장인석,문양수,손시환 한국가금학회 2012 한국가금학회 정기총회 및 학술발표회 Vol.29 No.-

구강편평상피세포암종에서 shikonin에 의한 상피간엽이행 억제

박단비,박봉수,강해미,유수빈,김인령 대한구강해부학회 2019 대한구강해부학회지 Vol.40 No.1

구강암은 주변 근육이나 골조직으로의 침습과 경부 림프절로 전이가 빈번히 일어나며, 전이가 일어난 환자의 5년 생존율은 약 40%로, 환자의 예후 개선을 위해 전이를 억제하는 항암제의 개발이 필요한 실정이다. 상피간엽이행 (EMT)이 일어난 세포에서는 이동성과 침습성이 증가하고, 암세포가 새로운 기관으로 전이가 일어나게 된다. 따라서, EMT를 억제하는 것은 암세포의 전이를 억제하는 치료 방법으로 고려 되고 있다. Shikonin은 지치에서 분리 정제된 물질로 항염증 효과가 널리 알려져 있다. 최근 shikonin은 다양한 암세포에서 세포자멸사 및 세포주기정지를 유도하고, 폐 및 위암세포의 전이성을 상실시키는 것이 밝혀졌다. 하지만 여전히 shikonin이 구강암에서 항전이 효과는 아직 불분명하다. 따라서 본 연구에서는 shikonin이 처리된 구강암 세포주에 대한 EMT 억제의 억제 효과를 확인 하였다. 본 연구에서 사용된 구강암 세포주 CAL-27로 세포생존율 및 세포증식율, 세포이동 및 침습, 단백질 및유전자의 발현을 확인하였다. CAL-27 세포는 shikonin 처리에 의해 생존율 및 증식율이 억제되었다. 또한, shikonin은 wound-healing 및 transwell invasion assay를 통해 CAL-27 세포의 이동 및 침습을 억제 하는것을 확인 하였다. Shikonin은 CAL-27 세포에서 epithelial marker 인 E-cadherin 의 protein 발현을 증가시켰으며, mesenchymal marker 인 N-cadherin, Snail 및 Slug 의 protein 및 RNA 발현을 감소 시켰다. 따라서, shikonin은 구강암세포주인 CAL-27의 상피간엽이행을 억제 함을 알 수 있었으며, 본 연구 결과는shikonin이 항전이성을 가지는 항암제로서의 가능성을 시사한다.

다문화·한부모여성의 사회자본이 생활만족도에 미치는 영향

박단비 한국가족자원경영학회 2016 한국가족자원경영학회 학술대회논문집 Vol.2016 No.11

Can ICT Development of Partner Countries Matter for Trade?

박단비,이미혜 한국EU학회 2023 EU학연구 Vol.28 No.1

This paper examines the role of ICT development on Korea’s export and import performance from 2013 to 2018 with its trading partner countries including some European countries such as France, Germany, Italy, the Netherlands and Switzerland. We investigate whether the relative development in ICT which is measured as the differences in ICT levels between Korea and its trading partner can stimulate trade between countries and whether the relative development of ICT can play a significant role to explain Korea’s trade with other countries. Our empirical analysis shows that development of the trade between two countries tend to grow faster as both countries participating in trade exhibit similar level of ICT. We also find that the development of ICT itself or the ICT development of a trading partner country does not appear to be significant in promoting trade between countries implying mutual development of ICT is necessary to increase trade between countries. Furthermore, it can mitigate the negative impact of geographical distance as the relative development of ICT becomes small. Our empirical analysis suggests that ICT development could enhance trade performance between countries similar to the findings in the existing literature and it emphasizes the relative development of ICT between trading countries matters to make ICT development contribute to boost international trade.

Financial Constraint and Corporate Employment: Evidence from the Emerging Economy

박단비 한국국제금융학회 2016 국제금융연구 Vol.6 No.1

This paper investigates the impact of financial constraint on corporate employment decision during the financial crisis using Korean firm-level data. During the financial crisis, credit constrained firms need to consider reducing employees to cut down the expenses and rescue from financial distress. We find that firm-specific determinants have significant effects on the relation between credit constraint and corporate employment. The empirical results show that in case of the SMEs, high loan ratio cause high probability to reduce employees. However, loan ratio does not have a significant effect on employment decision in case of large firms. We can induce that financial burden on SMEs lead to high unemployment rate in Korea. This study will provide policy implication that stimulating micro-finance on SMEs is also important to improve employment situation.

Is Vitamin D an Independent Risk Factor of Nonalcoholic Fatty Liver Disease?: a Cross-Sectional Study of the Healthy Population

박단비,권혁태,오승원,조희경,황승식,박진호,윤재문,이혜진,정고은,Sangjoon Ze,박재홍,배예슬,이아랑 대한의학회 2017 Journal of Korean medical science Vol.32 No.1

The association between vitamin D levels and nonalcoholic fatty liver disease (NAFLD) has been recognized. However, few studies showed independent associations between vitamin D deficiency and NAFLD after a sex-related adjustment for metabolic factors. We aimed to study whether vitamin D deficiency is an independent risk factor of NAFLD even after controlling for metabolic syndrome and visceral fat in both sexes. In this cross-sectional study, 7,514 Korean adults (5,278 men, 2,236 women) participated in a health check-up program. They underwent blood tests, abdominal computed tomography (CT) of the visceral fat area, and ultrasonography for NAFLD screening. Multiple logistic regression analysis was used to investigate the association of vitamin D deficiency with NAFLD according to the sex differences. Vitamin D deficiency is associated with NAFLD. The adjusted odds ratio (aOR) for NAFLD increased sequentially with decreasing vitamin D level, even after adjusting for metabolic syndrome and visceral fat. The subjects in the vitamin D sufficiency group (20–30 ng/mL) had an aOR for NAFLD of 1.18 (95% CI, 1.00–1.39), whereas the deficiency group (< 20 ng/mL) had an aOR of 1.29 (95% CI, 1.10–1.52). However, we have detected a significant sex-related interaction when analyzing the results. A significant relationship between vitamin D deficiency and NAFLD was found in men (aOR, 1.33; 95% CI, 1.11–1.60) but not in women.

닭 텔로미어 길이의 유전력 추정과 유전 전이 양상

박단비,손시환,Park, Dan Bi,Sohn, Sea Hwan 한국가금학회 2014 韓國家禽學會誌 Vol.41 No.3

텔로미어는 진핵 세포의 염색체 말단으로, 직렬 반복 DNA 염기 서열과 shelterin 단백질 복합체로 구성되어 있다. 텔로미어의 기능은 염색체를 보호하는 것으로 체세포의 텔로미어 길이는 세포 분열시 DNA 복제 결실로 인해 연령이 증가함에 따라 감소하는 경향이 있다. 그러나 유전적, 후생유전학적 및 환경적 수준에서 여러 가지 요인이 텔로미어 길이에 영향을 미친다. 따라서 본 연구에서는 닭의 텔로미어 길이의 유전력을 추정하고, 이들의 유전전이 양상을 살펴보고자 하였다. 텔로미어 길이는 백혈구를 이용하여 양적 형광접합보인법(Q-FISH)과 양적 중합효소 연쇄반응법(qRT-PCR)으로 분석하였다. 분석 결과, 텔로미어 길이의 유전력은 자손과 부모 회귀 분석에 의해 출생 시 0.9로 추정되었고, 10 주령 및 30주령 때 부 분산 분석에 의해 0.03과 0.04로 추정되었다. 부와 자손 간(r=0.348) 및 모와 자손 간(r=0.380) 텔로미어 길이는 모두 유의한 정의 상관 관계를 보였다. 따라서 닭 텔로미어의 유전 전이 양상은 부모 양쪽 모두로부터 비슷하게 자식에 영향을 미치는 것으로 판단된다. 더불어 암수 자손에 미치는 영향 또한 유사한 것으로 나타났다. 이러한 결과는 부모의 텔로미어 길이의 각인이 성염색체의 유전자가 아닌 상염색체의 유전자에 의해 조절되는 것을 의미한다. 또한, 산모 연령에 따른 출생 자손의 텔로미어 길이는 차이가 없는 것으로 나타났다. 따라서 모체의 연령이 출생 자손의 텔로미어 길이에 영향을 미치지 않는데, 이는 수정란의 초기 배아 단계에서 세포적 reprogramming이 이루어지기 때문으로 사료된다. Telomeres are the ends of the eukaryotic chromosomes and consist of a tandem repetitive DNA sequence and shelterin protein complex. The function of telomere is to protect chromosome. Telomere length in somatic cells tends to decrease with organismal age due to the end replication problem. However, several factors at the genetic, epigenetic and environmental level affect telomere length. In this study, we estimated heritability of telomere length and investigated inheritance of telomeres in a chicken. Telomere length of lymphocytes was analyzed by semi-quantitative polymerase chain reaction using telomere primer and quantitative fluorescence in situ hybridization using telomeric DNA probe. In results, heritability of telomere length was estimated 0.9 at birth by offspring-parent regression analysis and was estimated 0.03 and 0.04 at 10 and 30 weeks old, respectively, by parental variance analysis. There was a significant positive correlation in telomere length between father and their offspring (r=0.348), and mother and their offspring (r=0.380). In inheritance patterns of telomere length, the influence of paternal and maternal effect on their offspring was similar. The influence of inherited telomeres on male and female progeny was also roughly alike. These results implicated that imprinting of parental telomere length was regulated by autosomal genes, not sex linked genes. In addition, telomere length of offspring at birth did not differ along with their maternal age. Thus, maternal age does not affects telomere length in their offspring at birth owing to cellular reprogramming at early embryonic stage.

Fabrication and Characterization of Graphene Oxide-Coated Plate for Efficient Culture of Stem Cells

박단비,박재범,이지훈,Shim Chang Jae,김민성,이태용,임정옥 한국조직공학과 재생의학회 2021 조직공학과 재생의학 Vol.18 No.5

Background: For stem cell applications in regenerative medicine, it is very important to produce high-quality stem cells in large quantities in a short time period. Recently, many studies have shown big potential of graphene oxide as a biocompatible substance to enhance cell growth. We investigated if graphene oxide-coated culture plate can promote production efficiency of stem cells. Methods: Three types of graphene oxide were used for this study. They are highly concentrated graphene oxide solution, single-layer graphene oxide solution, and ultra-highly concentrated single-layer graphene oxide solution with different single-layer ratios, and coated on cell culture plates using a spray coating method. Physiochemical and biological properties of graphene oxide-coated surface were analyzed by atomic force microscope (AFM), scanning electron microscope (SEM), cell counting kit, a live/dead assay kit, and confocal imaging. Results: Graphene oxide was evenly coated on cell culture plates with a roughness of 6.4 ~ 38.2 nm, as measured by SEM and AFM. Young’s Modulus value was up to 115.1 GPa, confirming that graphene oxide was strongly glued to the surface. The ex vivo stem cell expansion efficiency was enhanced as bone marrow-derived stem cell doubling time on the graphene oxide decreased compared to the control (no graphene oxide coating), from 64 to 58 h, and the growth rate increased up to 145%. We also observed faster attachment and higher affinity of stem cells to the graphene oxide compared to control by confocal microscope. Conclusion: This study demonstrated that graphene oxide dramatically enhanced the ex vivo expansion efficiency of stem cells. Spray coating enabled an ultra-thin coating of graphene oxide on cell culture plates. The results supported that utilization of graphene oxide on culture plates can be a promising mean for mass production of stem cells for commercial applications. Background: For stem cell applications in regenerative medicine, it is very important to produce high-quality stem cells in large quantities in a short time period. Recently, many studies have shown big potential of graphene oxide as a biocompatible substance to enhance cell growth. We investigated if graphene oxide-coated culture plate can promote production efficiency of stem cells. Methods: Three types of graphene oxide were used for this study. They are highly concentrated graphene oxide solution, single-layer graphene oxide solution, and ultra-highly concentrated single-layer graphene oxide solution with different single-layer ratios, and coated on cell culture plates using a spray coating method. Physiochemical and biological properties of graphene oxide-coated surface were analyzed by atomic force microscope (AFM), scanning electron microscope (SEM), cell counting kit, a live/dead assay kit, and confocal imaging. Results: Graphene oxide was evenly coated on cell culture plates with a roughness of 6.4 ~ 38.2 nm, as measured by SEM and AFM. Young’s Modulus value was up to 115.1 GPa, confirming that graphene oxide was strongly glued to the surface. The ex vivo stem cell expansion efficiency was enhanced as bone marrow-derived stem cell doubling time on the graphene oxide decreased compared to the control (no graphene oxide coating), from 64 to 58 h, and the growth rate increased up to 145%. We also observed faster attachment and higher affinity of stem cells to the graphene oxide compared to control by confocal microscope. Conclusion: This study demonstrated that graphene oxide dramatically enhanced the ex vivo expansion efficiency of stem cells. Spray coating enabled an ultra-thin coating of graphene oxide on cell culture plates. The results supported that utilization of graphene oxide on culture plates can be a promising mean for mass production of stem cells for commercial applications.