Cementum is the mineralized tissue of the tooth. It is similar to bone in several aspects but it differs from bone. Human bone marrow stromal cells (BMSC) and human cementum derived cells (HCDC) (10,000 cells/cm²) were plated in 6 well plates as feeder cells. The next day, mouse bone marrow cells (1.5 million cells/cm²) were added. One group of these plates were incubated in serum-free conditioned medium (SFCM) generated from BMSC or HCDC supplemented with 2% FBS, parathyroid hormone (PTH), 1, 25 dihydroxyvitamin D₃ (Vit. D₃) and dexamethasone, or plain medium with the same supplements. Another group of plates were cocultured with BMSC or HCDC in plain medium supplemented with 2% FBS, PTH, Vit. D₃and dexamethasone. Plates grown without SFCM or coculture were used as controls. After 10 days, the cells were stained for tartrate-resistant acid phosphatase (TRAP). BMSC were found to support osteoclast formation under normal conditions. This was inhibited however by both SFCM generated from HCDC and also by coculture with HCDC. In addition, HCDC themselves did not support osteoclast formation under any conditions. Our results thus indicate that HCDC do not support osteoclast formation in vitro and that soluble factor (s) from HCDC may inhibit this process. In addition, we show that this inhibition also involves an active mechanism that is independent of osteoprotegerin, a feature that may distinguish cementoblasts from other cells present in periodontium.

본 연구는 vesicular stomatitis virus G glycoprotein (VSV-G)으로 피막이 형성되는 replication-defective MoMLV-based vector를 이용한 hTPO 헝질전환 닭의 생산에 관한 연구이다. 실험에 사용한 retrovirus vector의 구조는 hTPO 유전자의 발현 조절을 위해 internal promoter인 hCMV promoter를 이용하였으며 외래 유전자의 발현을 증가시키기 위해 woodchurk hepatitis virus posttranascriptional regulatory element (WPRE) 서열을 도입하였다. 재조합한 vector는 GP2 293 포장세포에 도입하여 virus를 생산하였으며 이 virus를 이용하여 감염시킨 여러 표적세포에서 hTPO의 발현과 생물학적 활성을 확인하였다. 재조합 hTPO의 생물학적 활성은 시판되고 있는 재조합 hTPO에 비해 우월한 것으로 확인되었다. hTPO 형질전환 닭의 생산을 위하여 1,000배 이상 고농도로 농축된 virus를 stage X 단계의 계란의 배반엽 층에 미세주입하여 대리난각 방법으로 배양하였다. 미세주입한 132개의 계란 중 21일 후에 11개의 계란에서 병아리가 부화하였으며 그중 4마리가 형질전환 개체로 확인되었다. 그러나 생산된 4마리 중 3마리가 부화 후 1개월 이내에 원인불명으로 사망하였다. 본 연구의 의의는 상업적 이용 가능성이 있는 생물학적 활성을 가진 사람의 cytokine 단백질의 대량 생산을 위한 생체 반응기로서의 형질전환 닭 개발의 시례를 제공하는데 있다.

Amino acid transporters are essential for the growth and proliferation in all living cells. Among the amino acid transporters, the system L amino acid transporters are the major nutrient transport system responsible for the Na+-independent transport of neutral amino acids including several essential amino acids. The L-type amino acid transporter 1 (LAT1), an isoform of system L amino acid transporter, is highly expressed in cancer cells to support their continuous growth and proliferation. 2-Aminobicyclo-(2,2,1)-heptane-2-carboxylic acid(BCH) is a model compound for study of amino acid transporter as a system L selective inhibitor. We have examined the effect and mechanism of BCH on cell growth suppression in FaDu human head and neck squamous cell carcinoma. The BCH inhibited the L-leucine transport in a concentration-dependent manner with a IC 50 value of 43.8±4.3μM. The majority of L-leucine uptake is, therefore, mediated by LAT1 in FaDu cells. The growth of FaDu cells was inhibited by BCH in the time- and concentration- dependent manners. The formation of DNA ladder was not observed with BCH treatment in the cells. Furthermore, the proteolytic processing of caspase-3 and caspase-7 in the cells was not detected by BCH treatment. These results suggest that the BCH inhibits the growth of FaDu human head and neck squamous cell carcinoma through the intracellular depletion of neutral amino acids for cell growth without apoptotic processing

Recent studies on nuclear transfer and induced pluripotent stem cells have demonstrated that differentiated somatic cells can be returned to the undifferentiated state by reversing their developmental process. These epigenetically reprogrammed somatic cells may again be differentiated into various cell types, and used for cell replacement therapies through autologous transplantation to treat many degenerative diseases. To date, however, reprogramming of somatic cells into undifferentiated cells has been extremely inefficient. Hence, reliable markers to identify the event of reprogramming would assist effective selection of reprogrammed cells. In this study, a transgene construct encoding enhanced green fluorescent protein (EGFP) under the regulation of human Oct4 promoter was developed as a reporter for the reprogramming of somatic cells. Microinjection of the transgene construct into pronuclei of fertilized mouse eggs resulted in the emission of green fluorescence, suggesting that the undifferentiated cytoplasmic environment provided by fertilized eggs induces the expression of EGFP. Next, the transgene construct was introduced into human embryonic fibroblasts, and the nuclei from these cells were transferred into enucleated porcine oocytes. Along with their in vitro development, nuclear transfer embryos emitted green fluorescence, suggesting the reprogramming of donor nuclei in nuclear transfer embryos. The results of the present study demonstrate that expression of the transgene under the regulation of human Oct4 promoter coincides with epigenetic reprogramming, and may be used as a convenient marker that non-invasively reflects reprogramming of somatic cells.

Our previous study showed that transgenic (TG) pigs harboring human EPO (hEPO) gene have been shown to have reproductive disorders, including low pregnancy rates, irregular estrus cycle and low little size. To investigate these reasons, we assessed estrus behavior (standing response) and plasma 17B-estradiol (E2) level, which partly reflect reproductive function, during the estrus cycles after synchronization and superovulation by hormone treatments. Then, we analysed blood composition and expression of hEPO gene in TG pigs. Pigs were injected with PG600. After 10 days, pigs were fed with Regumate porcine for 6 days. Blood samples were collected from jugular vein. Analysis of blood composition and E2 level were measured by Hemavet 950 and E2 ELISA kit, respectively. And, the expression of hEPO gene in reproductive organs was quantitated by real-time RT-PCR. The percentage of estrus behavior in TG was significantly decreased. Hematocrit (HCT), hemoglobin (Hb) concentration and red blood cell (RBC) number were significantly higher in TG than wild type (WT). On the other hand, high expression of hEPO gene in TG was observed in the mammary gland as well as in the uterus. Moreover, plasma E2 level was significantly higher in TG than WT. These results suggest that nonspecific expression of hEPO gene in the other organs of TG may affect blood composition and plasma E2 level, thereby causing reproductive disorders.

The endogenous retrovirus-like elements (HERVs) found on several human chromosomes are somehow involved in gene regulation, especially during the transcription level. HERV-H, located on chromosome Xp22, may regulate gastrin-releasing peptide receptor (GRPR) in connection with diverse diseases. By suppression subtractive hybridization screen on SV40-immortalized lung fibroblast (WI-38 VA-13), we discovered that expression of HERV-HX2, a clustered HERV-H sequence on chromosome X, was upregulated in immortalized lung cells, compared to that of normal cells. Expression of HERV-HX2 was then analyzed in various cell lines, including normal somatic cells, cancer cells, SV40-immortalized cells, and undifferentiated and differentiated human embryonic stem cells. Expression of HERV-HX2 was specifically upregulated in continuously-dividing cells, such as cancer cells and SV40-immortalized cells. Especially, HERV-HX2 in HeLa cells was highly upregulated during the S phase of the cell cycle. Similar results were obtained in hES cells, in which undifferentiated cells expressed more HERV-HX2 mRNA than differentiated hES cells, including neural precursor and endothelial progenitor cells. Taken together, our results suggest that HERV-HX2 is upregulated in cancer cells and undifferentiated hES cells, whereas downregulated as differentiation progress. Therefore, we assume that HERV-HX2 may playa role on proliferation of cancer cells as well as differentiation of hES cells in the transcriptional level.

Cordyceps militarisis well known as a traditional herbal ingredient, which has been used for patients suffering from cancer in oriental medicine. In this study we have investigated the biochemical mechanisms of anti-proliferative effects by C. militarisextract(CME) in human breast cancer MDA-MB-231 cells. It was found that CME treatment induced chromatin condensation, mitochondrial energization, annexin V staining and sub-G1 phase DNAcontent. These indicators of apoptosis correlate with the mitochondrial dependent pathway, which results in the activation of caspase-3 activity. Both the cytotoxic effect by CME treatment were significantly inhibited by z-DEVD-fmk, a caspase-3 inhibitor,demonstrating the important role of caspase-3 in the observed cytotoxic effect. Cotreatment of CME and LY294002, resulted in significantly induction of apoptosis. These results indicate that caspase-3 is a key regulator of apoptosis in response to CME in human breast cancer MDAMB- 231 through downregulation of Akt, and that the C. militaris extract may therefore have therapeutic potential against human breast cancer.

Agaricus blazei is well known as a traditional medicinal mushroom and it has been shown to exhibit immunostimulatory and anti-cancer activity. However, the cellular and molecular mechanism of apoptosis of cancer cells is poorly understood. In this study, we have investigated whether A. blazei extract (ABE) exerts anti-proliferative and apoptotic effects on human leukemia THP-1 cells. It was found that ABE induced a time- and dose-dependent increase in leukemia cells apoptosis through caspase-3 activation and PARP cleavage. Activation of caspase- 9 induced by ABE suggested that ABE-induced signaling was mediated through a mitochondrial death pathway. In addition, we observed an elevation of ROS and a consequent loss of mitochondrial membrane potential, further suggesting that ABE-induced death signaling was mediated through a mitochondrial oxygen stress pathway. The antioxidant Nacetylcysteine, however, opposed ABE-mediated mitochondrial dysfunction, caspase activation, and apoptosis, supporting the role of ROS in the apoptotic process. We conclude that ABE induces apoptosisin human leukemia cells through a reactive oxygen species and caspase-dependent mitochondrial pathway.

A mutation of UNCL, an inner nuclear membrane RNAbinding protein, has been found to eliminate mechanotransduction in Drosophila. UNCL is expressed in human periodontal tissue including in periodontal ligament (PDL) fibroblasts. However, it is unclear how a mechanical stimulus is translated into cellular responses in PDL fibroblasts. The aim of this study was to evaluate the effect of UNCl on mechanical stress related genes in PDL fibroblasts in response to mechanical stress. The mRNA of TGF-β, COX-2, and MMP-2 was up-regulated after UNCL inactivation in PDL fibroblasts under the compression force. Under the tensile force, inactivation of UNCL decreased the expression of Biglycan, RANKL, MMP-2, and TIMP-2 mRNAs while it increased the expression of TIMP-1. p38-MAPK was expressed in PDL fibroblasts under compression forces whereas phospho-ERK1/2, p65-NFkB, and c-fos were expressed under tension forces. The expression and phosphorylation of the mechanical stress related genes, kinases, and transcription factors were changed according to the types of stress. Furthermore, most of them were regulated by the inactivation of UNCL. This suggests that UNCL is involved in the regulation of mechanical stress related genes through the signaling pathway in PDL fibroblasts.

Human performance technology (HPT) has over 30 years of practice in real working settings and research in academia. The application of HPT principles, strategies, and models is aimed at solving performance problems and improving performance at all levels. Performance is the key word, and to improve performance is the value that HPT brings to individuals, organizations, and society. This article addresses questions centering on performance: 1) Where does the word performance come from? 2) What does performance really mean in HPT? And 3) what is HPT studying about performance? The concept of performance comes from Gilbert’s notion of worthy performance which distinguishes behavior from accomplishment. Specifically, accomplishment is the positive and valued outcomes of behavior and the transaction from behavior to accomplishment is the performance that HPT focuses on. Performance is not a simple term, but a complex system in which factors are interacting with each other to affect performance. As a science of performance, HPT applies systematic approaches to investigate the relationship between and interaction among the affecting factors in a performance system.

The purpose of this article is to examine the possibilities of Human Performance Technology (HPT) under the background of global economy. First, two kinds of culture, national culture and organizational culture are introduced and compared. Next, the impact of cultures on human learning and working performance is examined in the aspects of learning and training, management, and global cooperation. And then the article proposes different strategies for managing the factor of culture to achieve desired performance, including diffusion and adaption. In addition, it is considered that how the proposed strategies can be utilized for public education systems. Finally, further research agenda is addressed Living in a culture is like swimming in the water is for a fish: one does not recognize one’s basic cultural values and beliefs as being there. They are the water one swims in. Everything one does takes this water into account unconsciously (Addison & Wittkuhn, 2001, p. 16). Pushing harder and harder on familiar solutions, while fundamental problems persist or worsen, is a reliable indicator of nonsystemic thinking- what we often call the “what we need here is a bigger hammer” syndrome (Senge, 1994, p. 61).

대부분의 경영분석가들은 뷰티산업이 미래의 주요산업의 하나가 될 것이라고 예견하고 있다. 뷰티산업은 뷰티에 관련된 서비스와 상품을 포함하고 있는데, 이 시장에서의 경쟁은 더욱 치열해지고 있다. 뷰티 서비스와 뷰티 상품을 마케팅하기 위해서는 뷰티가 측정될 수 있어야 하지만, 실제적으로 뷰티를 측정할 수 있는 수단은 사실상 개발되어 있지 않다. 본 연구에서는 Langmeyer and Shank(1994)의 연구를 바탕으로 인물의 매력을 단일의 차원이 아닌 다차원으로 규명하고자 하였다. 총 258명의 대학생 응답자를 대상으로 인물의 매력에 관련된 뷰티의 차원에 관련된 설문을 실시했고, 이를 바탕으로 인물의 매력에 관련된 뷰티의 차원을 도출하고, 뷰티 측정에 대한 관리적 시사점을 제시하였다. 본 연구에서는 수행된 정량적 분석에 기초하여 최종적으로 인물 매력에 관련된 4가지 뷰티 차원을 도출하였는데, 2개 차원은 인물의 내면의 아름다움에 관련된 것(역동적 성격, 배려)이었고, 나머지 2개 차원은 인물의 외면의 아름다움에 관련된 것(형상, 스타일)이었다. 또한 본 연구에서는 추가적으로 응답자 특성에 따라 아름다움 인식에 차이가 있는지 분석하였다. 응답자 특성으로는 성별, 외적 아름다움의 인식 차이, 자신의 외모 만족도가 고려되었다. 분석결과는 자신의 외모 만족도와 아름다움의 인식 가치가 본 연구에서 도출된 아름다움 차원에 있어서 아름다움 인식에 영향을 미친다는 것을 보여주고 있다: 1)자신의 외모 만족도가 높은 경우 전반적으로 외모차원과 심성차원의 아름다움을 모두 높게 평가하는 것으로 나타났다, 2)아름다움의 인식 가치가 높은 경우 외면의 아름다움 차원을 내면의 아름다움 차원보다 상대적으로 더 긍정적으로 평가하는 것으로 나타났다.

The purpose of the present study is to investigate the optimal wavelength, frequency and energy density for set up the photobiologic treatment of periodontal disease. To establish the present study, λ scan of 500㎚ to 900㎚ was used to search the optimal wavelength for maximal proliferation of human gingival fibroblasts. Cell proliferation assay was carried out as MTT assay. Light intensity of 0.8 to 3.25mW, frequency of 0 to 584㎐ and 0 to 2hours was applied for investigation of optimal energy density, frequency and applied duration. Finally, 628㎚ with 1mW/cm2 for 1hour of LED irradiation resulted in maximal proliferation of gingival fibroblasts. These results suggest that LED irradiation on gingival fibroblast show different proliferation according to the condition of irradiation, and demonstrate that LED irradiation can control the quantity of cell proliferation.